text:
\section{Introduction}\label{sec:Introduction}

\section{Introduction}\label{sec:Introduction}
Machine-type communications (MTC), also called machine-to-machine (M2M) communications, is a type of transmission which does not directly involve human intervention. Examples include smart metering, telemetry and sensors~\cite{shafiq2013large}. This type of transmission is projected to be an important part of fifth generation (5G) communication systems~\cite{boccardi2014five}.

It is expected that the number of Machine-type Devices (MTDs) will be at least two orders of magnitude higher than the number of human-type users in a given cell~\cite{yang2014m2m}. Also, MTC traffic from several devices can be correlated in time and space, since e.g. sensors can react to external events such as a fire or traffic accident, which have a spatial characteristic. This sort of behaviour can result in traffic spikes or bursts which can put stress on the receiver (e.g. a base station (BS)) since MTC traffic is usually uplink-dominated. It is therefore desirable to have tractable models that can be used to assess the impact of this type of traffic on the BS.

In this paper, we formulate a traffic model based on tools from stochastic geometry that takes into account the spatial aspect of devices and events. Motivated by the observation that traffic from individual MTDs is often small, while the total traffic at the BS can be large~\cite{shafiq2013large}, we derive analytical expressions for the expected total rate of the devices. It is assumed that each device can be in two modes, regular and alarm, depending on the proximity of the device location to the event locations. We also derive a Markov chain model and provide an analytical expression which is a good approximation for the expected total rate when the time spent in the alarm state is low

\section{Background and Related Works}\label{sec:BackgroundandRelatedWorks}
Models for M2M traffic can broadly be categorized into two groups, source models and aggregated models~\cite{centenaro2015study}. In a source model, each source has its own set of tunable parameters which control its individual traffic characteristics. In an aggregated traffic model all sources have a common set of parameters. A source model thus allows for more fine-grained control; however this comes at a higher cost in computational complexity because of a higher number of parameters.

Traffic modeling for MTC has been considered by the 3rd Generation Partnership Project (3GPP) in~\cite{3GPPTR37868}. They propose two models, one accounting for uncoordinated arrivals and one accounting for coordinated arrivals. In the former, the packet arrivals are specified to follow a uniform distribution in $[0,T_u]$, where $T_u$ is $60$ sec. The latter model uses a scaled Beta distribution over $[0,T_b]$, where $T_b$ is $10$ sec, with parameters $\alpha=3$ and $\beta=4$. In~\cite{madueno2016reliable}, other values of $\alpha$ and $\beta$ are derived numerically for different types of alarm events

Modeling of human-type traffic (such as telephone traffic) is usually done by means of Poisson processes (PPs). However, PPs are not well suited for modeling coordinated traffic, which is expected to play a large role in MTC applications. To address this, many papers consider Markov modulated Poisson processes (MMPPs). In such a model, a source can be in a number of states $\mathcal{S} = \{s_1, \ldots, s_m\}$ and the state transitions are governed by an irreducible Markov chain. When the process is in state $s_i \in \mathcal{S}$, it generates Poisson-distributed traffic with rate $\lambda_i$. A variant of this is the Markov modulated Bernoulli process (MMBP), where Bernoulli-distributed traffic with state-dependent probability $p_i$ is generated~\cite{ibe2013markov}. Another model used especially in Internet traffic modeling is the Markovian arrival process (MAP). A MAP can be in a number of states $s_i \in \mathcal{S}$, also termed \emph{phases}~\cite{ibe2013markov}. The process can then either enter another phase with rate $\gamma$, or, with rate $\lambda$, enter another phase and generate a packet. Contrary to the MMBP and MMPP, where the interarrival times of packets are geometrically and exponentially distributed respectively, the MAP allows for more general interarrival time distributions.

To take into account possible dependency between MTDs,~\cite{laner2013traffic} considers a model where each device can be in regular or alarm state. Two state-transition matrices $\mathbf{P}_{\mathrm{U}}$ and $\mathbf{P}_{\mathrm{C}}$ are defined, the former representing uncoordinated behaviour and the other, coordinated behaviour. The model is a source model where each device has its own transition matrix which is a convex combination of $\mathbf{P}_{\mathrm{U}}$ and $\mathbf{P}_{\mathrm{C}}$. The coordination between devices is modeled via a parameter $\delta_i$ for each device $i$, as well as a global background process $\theta(t)$, which takes values uniformly in $[0,1]$. It is shown that the model has a lower computational complexity compared to a full source model. This model is extended in~\cite{centenaro2015study} and used for evaluating a random access scheme supporting human-type and MTD traffic.

A spatio-temporal traffic model for MTDs using queueing theory and stochastic geometry is analyzed in~\cite{gharbieh2017spatiotemporal}. They compare three different access protocols for MTC and derive success probabilities, average queueing delays and waiting times. Stability regions for the three protocols are given, which can be used for scalability assessment. Compared to this work, our model allows for devices to be triggered by external events.

Reference~\cite{madueno2016reliable} formulates a spatial correlation model of MTDs using the IEEE802.11ah protocol. As in other works, each device can be in two states, regular or alarm, with transition probabilities described by the model in~\cite{laner2013traffic}. In~\cite{madueno2016reliable}, they define the background process $\theta(t)$ to be a function of alarm onset and velocity, as well as location. They give a numerical expression for the total rate, albeit not in closed form.

A two-state traffic model for automotive M2M applications based on a coupled MAP is proposed in~\cite{grigoreva2017coupled}. Here, any car can trigger an event; then other cars go into event mode if the distance to the car triggering the event is less than a specified threshold. They show that this model better captures burstiness than a PP model

In the present paper, we use the theory of spatial Poisson point processes (PPPs) to model the position of devices and event epicenters. We also define a function which models the influence of events on device traffic. Even though spatial modeling has been considered in~\cite{madueno2016reliable, grigoreva2017coupled}, our use of PPPs allows us to obtain tractable analytical expressions for the total rate, and thus avoids computationally expensive simulations. Also, we include the temporal aspect in the model via defining a Markov chain for each device, derive an approximation of the expected total rate, and show via numerical simulations that this approximation is quite close. We study the temporal correlation of the traffic in the Markov chain model via the autocovariance function. Even though our model is a source model, the theory of PPPs can still be applied and provides accurate results.

\section{Proposed Model}\label{sec:ProposedModel}
Let $C$ be the coverage disk of a BS (located at the origin of the disk) of radius $R$ and let $N$ devices be deployed randomly and independently in $C$.
Each MTD can be in one of two states: regular (R) and alarm (A). Time is slotted. In timeslot $k$, MTD $i$ generates traffic with rate $R_i(k)$, depending on its current state. In the regular state, it generates traffic with rate $R_{\mathrm{R},i}$, and in alarm state, the rate is $R_{\mathrm{A},i}$. In this work, all devices are of the same type, i.e. $R_{\mathrm{R},i} = R_{\mathrm{R}}$ and $R_{\mathrm{A},i} = R_{\mathrm{A}}$, $\forall i=1,\ldots,N$.

\subsection{Modeling the Device Locations and Event Epicenters}\label{sub:DeviceModeling}
The MTDs are deployed in the coverage disk of the BS according to a homogeneous PPP $\Phi_{\mathrm{M}}$ with density $\lambda_{\mathrm{M}}$. The event epicenters are represented by a homogeneous PPP $\Phi_{\mathrm{E}}$ with density $\lambda_{\mathrm{E}}$ in the Euclidean plane. The processes $\Phi_{\mathrm{M}}$ and $\Phi_{\mathrm{E}}$ are assumed independent.

We choose to use PPPs because typical nodes can be reasonably assumed to be randomly deployed in the plane, in particular since we are not targeting a specific application. Furthermore, this choice allows for analytical tractability and can serve as a good indicator of performance.

Fig.~\ref{fig:ScenarioEventDevicesBaseStation} shows an example of a deployment of devices in a cell. Event epicenters are indicated with red crosses. Note that events from outside the BS coverage area can influence devices inside it. In the figure, three devices are in alarm mode (transmission indicated with solid red arrows) and two devices are in regular mode (transmission indicated with dashed blue arrows).

\begin{figure}[t]
	\centering
		\includegraphics[width=0.7\linewidth]{ScenarioEventDevicesBaseStation.pdf}
	\caption{Conceptual deployment of devices in a cell, with a BS at the center. Event epicenters are indicated by red crosses. The influence of an event is coded in the shade intensity: The darker the shade, the stronger the influence.}
	\label{fig:ScenarioEventDevicesBaseStation}
\end{figure}

\subsection{Modeling Alarm Probabilities}\label{sub:ModelingAlarmProbabilities}

In order to capture the effect of a given event on a device, we define a function with gives the probability $p$ that an alarm is triggered in a device at location $\mathbf{x}$ by an event with epicenter at location $\mathbf{y}$ in the Euclidean plane $\mathbb{R}^2$. This function depends on the distance between the two locations. The definition is given below.
\begin{definition*}[Alarm Triggering Probability Function (ATPF)]\label{def:ECF}
An \emph{ATPF} is a function $f$ defined as
\begin{equation}\label{eqn:ATPFdefinition}
	f : [0,\infty) \to [0,1], \hspace{1cm} d \mapsto f(d) = p,
\end{equation}
having a finite first moment
\end{definition*}
In applications, $f(d)$ is typically non-increasing to represent a decaying influence of events on devices as the distance $d$ increases.

\subsection{Modeling Discrete Rates}\label{sub:ModelingDiscreteRates}
Let $E_{\mathbf{x}\mathbf{y}}$ be the event that a device at location $\mathbf{x}$ is triggered into alarm mode by an event with epicenter at $\mathbf{y}$.
Let $\overline{E_{\mathbf{x}\mathbf{y}}}$ be the complement of $E_{\mathbf{x}\mathbf{y}}$ and let $p_{\mathbf{x}\mathbf{y}} = \Pr\{ E_{\mathbf{x}\mathbf{y}}\}$ be the probability of $E_{\mathbf{x}\mathbf{y}}$. The probability of this device being in alarm mode i
\begin{align}
p_\mathbf{x} &= \Pr\{ \text{Device at $\mathbf{x}$ is  triggered by at least one event} \}  \nonumber \\
&= 1 - \Pr\{ \text{No event triggers device at $\mathbf{x}$} \} \\
&= 1 - \Pr \left\{ \bigcap_{\mathbf{x} \in \Phi_{\mathrm{E}}} \overline{E_{\mathbf{x}\mathbf{y}}} \right\} = 1 - \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} \Pr \left\{ \overline{E_{\mathbf{x}\mathbf{y}}} \right\} \label{eqn:probAlarmDerivation} \\
&= 1 - \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} (1 - p_{\mathbf{x}\mathbf{y}}) \label{eqn:FinalExpressionPi},
\end{align}
where in~\eqref{eqn:probAlarmDerivation}, we used the assumption that alarms resulting from different events are independent. Note that $0 \le 1-f(d_{\mathbf{x}\mathbf{y}}) \le 1$, where $d_{\mathbf{x}\mathbf{y}} = \Vert \mathbf{x} - \mathbf{y} \Vert$  and $p_{\mathbf{x}\mathbf{y}} = f(d_{\mathbf{x}\mathbf{y}})$.

The state of a device at location $\mathbf{x}$, $S_\mathbf{x}$ is a random variable which depends on $\Phi_{\mathrm{M}}$ and $\Phi_{\mathrm{E}}$. The statistical dependence between $S_\mathbf{x}$, the corresponding rate $R_\mathbf{x}$ and $\Phi_{\mathrm{M}}$ and $\Phi_{\mathrm{E}}$ is represented as a directed graphical model, as shown in Fig.~\ref{fig:StateEventDependence}. In the figure, the blue box (called a plate, see e.g.~\cite[Ch. 8]{bishop2006pattern}) around $\mathbf{x}, S_\mathbf{x}$ and $R_\mathbf{x}$ indicates $\vert \Phi_{\mathrm{M}} \vert$ instances of each of them, where $\vert \Phi_{\mathrm{M}} \vert$ is the cardinality of $\Phi_{\mathrm{M}}$. Similarly, the right plate around $\mathbf{y}$ indicates an infinite but countable number of instances of $\mathbf{y}$.
Note that $S_\mathbf{x}$ depends on an infinite number of parameters, since $\Phi_{\mathrm{E}}$ contains an infinite number of points almost surely. However, $S_\mathbf{x}$ is still well-defined, as long as the ATPF is chosen according to the definition and $R < \infty$.

Since each device at location $\mathbf{x}$ has its own probability $p_\mathbf{x}$ of going into alarm mode, the present model can be considered a source model. Also, the model allows for correlated behaviour, since for two devices at locations $\mathbf{x}$ and $\mathbf{x}'$ respectively, where $\mathbf{x} \neq \mathbf{x}'$, both $S_\mathbf{x}$ and $S_{\mathbf{x}'}$ depend on all points of $\Phi_{\mathrm{E}}$

We consider two ways of modeling the states $S_\mathbf{x}(k)$, with slot index $k$. Below, we model them as i.i.d. Bernoulli random variables, later in Sec.~\ref{sec:MarkovchainAnalysis} we model them as a Markov chain. For the former case
\begin{equation}\label{eqn:BernoulliModelCases}
S_\mathbf{x}(k) = \begin{cases} \text{Regular} & \text{with prob.}\; 1-p_\mathbf{x} \\ \text{Alarm} & \text{with prob.} \;p_\mathbf{x} \end{cases},
\end{equation}
with $p_\mathbf{x}$ given in~\eqref{eqn:FinalExpressionPi}. Then, each realization of $\Phi_{\mathrm{E}}$ and $\Phi_{\mathrm{M}}$ results in state sequences $\{S_\mathbf{x}(k)\}_{k=1}^\infty$, which are i.i.d. Bernoulli processes.
\def0.85\columnwidth{0.55\columnwidth}
\begin{figure}[t]
	\centering
		\import{/}{StateEventDependence.pdf_tex}
	\caption{Dependence of the rate of the devices on the two PPPs, illustrated as a directed graphical model.}
	\label{fig:StateEventDependence}
\end{figure}

\section{Derivation of the Expected Total Rate}\label{sec:ExpectedAggegrateRateDerivation}

\subsection{Bernoulli Traffic Generation}\label{sub:BernoulliTrafficGeneration}
In this subsection, we assume that each device generates traffic according to a Bernoulli process.

The expected rate of the device at location $\mathbf{x}$ i
\begin{align}
R_\mathbf{x} &= p_\mathbf{x} R_{\mathrm{A}} + (1-p_\mathbf{x})R_{\mathrm{R}}.
\end{align}
By substituting the expression of $p_\mathbf{x}$ in~\eqref{eqn:FinalExpressionPi}, we get
\begin{align}
R_\mathbf{x} &= p_\mathbf{x} R_{\mathrm{A}} + (1-p_\mathbf{x})R_{\mathrm{R}} \\
&= \left( 1 - \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} (1 - p_{\mathbf{x}\mathbf{y}}) \right) R_{\mathrm{A}} + \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} (1 - p_{\mathbf{x}\mathbf{y}}) R_{\mathrm{R}} \\
&= R_{\mathrm{A}} + ( R_{\mathrm{R}} - R_{\mathrm{A}} ) \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} (1 - p_{\mathbf{x}\mathbf{y}}).
\end{align}

The total rate $R_{\mathrm{T}} = \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} R_\mathbf{x}$ of all devices is then
\begin{equation}\label{eqn:totalRateNotExpectation}
\sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} \left( R_{\mathrm{A}} + ( R_{\mathrm{R}} - R_{\mathrm{A}} ) \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} (1 - p_{\mathbf{x}\mathbf{y}}) \right).
\end{equation}
The goal is now to obtain an expression for the total rate averaged over $\Phi_{\mathrm{M}}$ and $\Phi_{\mathrm{E}}$. This expression is given in the following theorem:

\begin{thm*}\label{thm:totalRateAnalytical}
Let $\Phi_{\mathrm{M}}$ and $\Phi_{\mathrm{E}}$ be independent homogeneous PPPs with densities $\lambda_{\mathrm{M}}$ and $\lambda_{\mathrm{E}}$ respectively, and $f$ be a valid ATPF. Let $C$ be the circular coverage disk of the BS, and $R$ its radius. Then the expected total rate averaged over $\Phi_{\mathrm{M}}$ and $\Phi_{\mathrm{E}}$ is
\begin{align}\label{eqn:totalRateAnalytical}
\overline{R_{\mathrm{T}}} &\triangleq \mathbb{E} \left[R_{\mathrm{T}} \right] =  \lambda_{\mathrm{M}} \pi R^2 \cdot \nonumber \\
& \left( R_{\mathrm{A}} + (R_{\mathrm{R}} - R_{\mathrm{A}})  \int_C \exp \left( -2\pi\lambda_{\mathrm{E}} \int_{0}^\infty f(r)r \mathrm{d}r \right) \right).
\end{align}
\end{thm*}
\begin{proof}
Taking the expectation over $\Phi_{\mathrm{M}}$ and $\Phi_{\mathrm{E}}$ in~\eqref{eqn:totalRateNotExpectation}, we get
\begin{align}
&\mathbb{E} \left[ \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} \left( R_{\mathrm{A}} + ( R_{\mathrm{R}} - R_{\mathrm{A}} ) \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} (1 - p_{\mathbf{x}\mathbf{y}}) \right) \right] \\ \nonumber
&= \mathbb{E} \left[ \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} R_{\mathrm{A}} \right] + \mathbb{E} \left[ \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} (R_{\mathrm{R}} - R_{\mathrm{A}}) \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}}(1-p_{\mathbf{x}\mathbf{y}}) \right] \\
&= \lambda_{\mathrm{M}} \int_C R_{\mathrm{A}} + (R_{\mathrm{R}} - R_{\mathrm{A}}) \mathbb{E} \left[ \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}}(1-p_{\mathbf{x}\mathbf{y}}) \right] \label{eqn:CampbellThm1} \\ \nonumber
&= \lambda_{\mathrm{M}} \pi R^2 R_{\mathrm{A}} \\ & \hspace{1cm}+ (R_{\mathrm{R}} - R_{\mathrm{A}}) \mathbb{E} \left[ \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} \mathbb{E} \left[ \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} (1-p_{\mathbf{x}\mathbf{y}}) \right] \right] \label{eqn:LastTermInnerExpectation},
\end{align}
where in~\eqref{eqn:CampbellThm1} Campbell's Theorem~\cite[Thm. 4.1]{chiu2013stochastic} was used for a PPP with density $\lambda_{\mathrm{M}}$ over a circular disk $C$ of radius $R$.

To compute the inner expectation in the second term of~\eqref{eqn:LastTermInnerExpectation}, we use the probability generating functional (PGFL) of a PPP with density $\lambda_{\mathrm{E}}$~\cite[p.125]{chiu2013stochastic}. After changing to polar coordinates, we get for each summand in~\eqref{eqn:LastTermInnerExpectation}
\begin{equation}
\mathbb{E} \left[ \prod_{\mathbf{y} \in \Phi_{\mathrm{E}}} (1 - f(d_{\mathbf{x}\mathbf{y}})) \right] = \exp \left( -2\pi \lambda_{\mathrm{E}} \int_0^\infty f(r) r \mathrm{d}r \right).
\end{equation}
Then, the outer expectation in~\eqref{eqn:LastTermInnerExpectation} equals
\begin{align}
\mathbb{E} \left[ \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} \exp \left( -2\pi \lambda_{\mathrm{E}} \int_0^\infty f(r) r \mathrm{d}r \right) \right]. \label{eqn:secondEquationCampbell}
\end{align}
Using Campbell's Theorem, the expectation in~\eqref{eqn:secondEquationCampbell} can be expressed as
\begin{align}
&\lambda_{\mathrm{M}} \int_C \exp \left( -2\pi \lambda_{\mathrm{E}} \int_0^\infty f(r) r \mathrm{d}r \right) \\ &= \lambda_{\mathrm{M}} \pi R^2 \exp \left( -2\pi \lambda_{\mathrm{E}} \int_0^\infty f(r) r \mathrm{d}r \right).
\end{align}
Combining the above results and rearranging yields
\begin{align}
\lambda_{\mathrm{M}} \pi R^2 \left( R_{\mathrm{A}} + (R_{\mathrm{R}} - R_{\mathrm{A}})\exp \left( -2\pi \lambda_{\mathrm{E}} \int_0^\infty f(r) r \mathrm{d}r \right) \right). \label{eqn:FinalExpressiontotalRate}
\end{align}
\end{proof}

\begin{ex*}[Exponential ATPF]\label{ex:expATPF}
Consider an exponentially decaying function of the distance $d$
\begin{equation}\label{eqn:ExpATPF}
f(d) = \exp(-d).
\end{equation}
It is easy to see that~\eqref{eqn:ExpATPF} satisfies the conditions in the Definition of an ATPF. In this case, $p_{\mathbf{x}\mathbf{y}} = \exp ( -d_{\mathbf{x}\mathbf{y}})$. The expected total rate is
\begin{equation}\label{eqn:rateExpATPF}
\overline{R_{\mathrm{T}}} = \lambda_{\mathrm{M}} \pi R^2 (R_{\mathrm{A}} + (R_{\mathrm{R}} - R_{\mathrm{A}}) \exp( -2\pi \lambda_{\mathrm{E}} )),
\end{equation}
which follows since $\int_0^\infty \exp(-r) r \mathrm{d} r = 1$.
Using~\eqref{eqn:rateExpATPF}, we can see that $\lambda_{\mathrm{E}} \to 0$ (i.e. no event) implies $\overline{R_{\mathrm{T}}} = \lambda_{\mathrm{M}} \pi R^2 R_{\mathrm{R}}$ (only regular traffic), while $\lambda_{\mathrm{E}} \to \infty$ implies $\overline{R_{\mathrm{T}}} = \lambda_{\mathrm{M}}\pi R^2 R_{\mathrm{A}}$ (only alarm traffic), as expected.
\end{ex*}

\section{Markov chain Analysis}\label{sec:MarkovchainAnalysis}
In this section, we extend the model, enabling each device to stay in alarm mode for a duration geometrically distributed with parameter $q$.

We characterize the state of a device at location $\mathbf{x} \in \Phi_{\mathrm{M}}$ at a given time $k$ as a Markov process, i.e.
\begin{equation}
\Pr \{S_\mathbf{x}(k) \mid S_\mathbf{x}(k-1), \ldots, S_\mathbf{x}(0) \} = \Pr \{ S_\mathbf{x}(k)\mid S_\mathbf{x}(k-1) \}
\end{equation}
where $S_\mathbf{x}(k)$ can take two different values, Regular and Alarm. The state transition diagram is shown in Fig.~\ref{fig:StateTransitionDiagram}, and the state transition matrix is
\begin{equation}\label{eqn:StateTransitionMatrixSourceModel}
\mathbf{P}_\mathbf{x} = \begin{bmatrix} 1-p_\mathbf{x}& p_\mathbf{x} \\ 1-q & q\end{bmatrix}.
\end{equation}
This Markov chain is ergodic; it has a unique steady-state probability vector $\pi_\mathbf{x} = [\pi_{\mathbf{x},A}, \; \pi_{\mathbf{x},R}]$, where $\pi_{\mathbf{x},A}$ ($\pi_{\mathbf{x},R}$) is the probability of alarm (regular) state. The vector $\pi_\mathbf{x}$ can be found by solving the system of linear equations
\begin{equation}
	\pi_\mathbf{x} \mathbf{P}_\mathbf{x} = \pi_\mathbf{x},
\end{equation}
together with the normalizing condition $\pi_{\mathbf{x},A} + \pi_{\mathbf{x},R} = 1$:
\begin{equation}\label{eqn:SteadyStateProbs}
	\pi_{\mathbf{x},A} = \frac{p_\mathbf{x}}{1+p_\mathbf{x}-q}, \hspace{1cm} \pi_{\mathbf{x},R} = \frac{1-q}{1+p_\mathbf{x}-q}.
\end{equation}

We assume that the initial state $S_\mathbf{x}(0)$ is distributed according to the above steady-state distribution
\def0.85\columnwidth{0.85\columnwidth}
\begin{figure}[t]
	\centering
		\import{/}{StateTransitionDiagram.pdf_tex}
	\caption{State transition diagram of the Markov chain model describing the temporal behaviour of the $i$th device.}
	\label{fig:StateTransitionDiagram}
\end{figure}

Note that by setting $q = p_\mathbf{x}$, we recover the model defined in~\eqref{eqn:BernoulliModelCases}. Also, by replacing each $p_\mathbf{x}$ in~\eqref{eqn:SteadyStateProbs} with $\overline{p} \triangleq \mathbb{E} \left[  p_\mathbf{x} \right]$, we can approximate the total rate $R(k) = \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}}R_\mathbf{x}(k)$ of the Markov chain model in a low complexity manner:
\begin{align}
	\widetilde{R_{\mathrm{T}}} &= \mathbb{E} \left[ \sum_{\mathbf{x} \in \Phi_{\mathrm{M}}} \left( \frac{\overline{p}}{1+\overline{p}-q} R_{\mathrm{A}} + \frac{1-q}{1+\overline{p}-q} R_{\mathrm{R}} \right) \right] \\
	&= \lambda_{\mathrm{M}} \pi R^2 \left( \frac{\overline{p}}{1+\overline{p}-q} R_{\mathrm{A}} + \frac{1-q}{1+\overline{p}-q} R_{\mathrm{R}} \right).\label{eqn:totalRateApproxMarkovchain}
\end{align}
We comment on this approximation in Sec.~\ref{sec:NumericalResults}. Note that by setting $q=0$ and multiplying $p_\mathbf{x}$ by a factor $\theta(t)$ in the Markov chain, we recover the models of~\cite{laner2013traffic, centenaro2015study}.

\subsection{Temporal Characteristics of the Model}\label{sub:TemporalCorrelationoftheModel}
We study the temporal characteristics of the Markov chain model through the autocovariance function (ACF) of the total rate

The reason for introducting the ACF is that we want to see the effect of the parameters $\lambda_{\mathrm{E}}$, $\lambda_{\mathrm{M}}$ and $q$ on the long-term temporal dependence of the model. We suspect that by letting $q \to 1$, the autocovariance function will decay slowly, since devices triggered by an alarm will stay in the alarm mode for a longer period of time, implying temporally correlated traffic. The ACF of $R(k)$ is defined as
\begin{equation}\label{eqn:ACF}
	C_{RR}(k,k') = \frac{1}{\sigma_{\mathrm{R}}^2}\mathbb{E} \left[ (R(k)-\mu_{\mathrm{R}})(R(k')-\mu_{\mathrm{R}}) \right],
\end{equation}
where $k, k' = 1,2,\ldots$ and $\mu_{\mathrm{R}}$ and $\sigma_{\mathrm{R}}^2$ are the mean and variance of $R(k)$ respectively. The expectation is taken over the distribution of $R(k)$.

Note that we use the autocovariance function instead of the autocorrelation, because we want to compare the temporal dependence for various settings of the  parameters $\lambda_{\mathrm{E}}$, $\lambda_{\mathrm{M}}$ and $q$ on the same scale

We estimate the ACF of $R(k)$ via Monte Carlo (MC) simulations as follows. For any trial, the unbiased sample autocovarianc
\begin{equation}\label{eqn:sampleACF}
	\widehat{C}_{RR}(k) = \frac{1}{(N_S-k)\sigma_{\mathrm{R}}^2}\sum_{i=1}^{N_S-k-1}(R(i)-\mu_{\mathrm{R}})(R(i+k)-\mu_{\mathrm{R}}),
\end{equation}
is computed.
Here $N_S$ is the number of time samples. Note that in our case, ~\eqref{eqn:sampleACF} is conditioned on realizations of $\Phi_{\mathrm{E}}$ and $\Phi_{\mathrm{M}}$. Also, the mean and variance are replaced by their respective sample estimates. Averaging $\widehat{C}_{RR}(k)$ over the PPP realizations via MC simulations, we get $\overline{C_{RR}}(k)$.
In the next section, the role of this quantity on the traffic will be discussed. The derivation of the ACF is left for future work.

\section{Numerical Results}\label{sec:NumericalResults}
In this section, we show some quantitative results illustrating the behavioural features of the Bernoulli and Markov chain models, using MC simulations done in Matlab. In the simulations, devices and events are deployed independently and traffic is generated either using the Bernoulli or Markov chain models. The resulting total rate is then averaged over event and device realizations. We use the exponential ATPF~\eqref{eqn:ExpATPF} in all simulations. The simulation parameters are listed in Tab.~\ref{tab:SimulationParameters}. They are used unless otherwise specified.

\begin{table}[b]
	\caption{Simulation parameters.}
	\centering
			\begin{tabular}{ c l c }
		  	\hline
  			Parameter & Description & Value\\
				\hline
				$s$ & Observation window size & $100$ m \\
				$\lambda_{\mathrm{M}}$ & Device density & $10^{-1}$ ${\text{nodes}}/{\text{m}^2}$ \\
				$\lambda_{\mathrm{E}}$ & Event density & $10,\ldots, 10^{-5}$ ${\text{events}}/{\text{m}^2}$ \\
				$R_{\mathrm{A}}$ & Rate in alarm mode& $1$ $\text{packet}/\text{slot}$ \\
				$R_{\mathrm{R}}$ & Rate in regular mode& $0.01$ $\text{packet}/\text{slot}$ \\
				$R$ & Cell radius & $20$ m \\
				\hline
			\end{tabular}
	\label{tab:SimulationParameters}
\end{table}

\subsection{Bernoulli Process Model}\label{sub:BernoulliProcessModel}
Fig.~\ref{fig:rateAnaSimBern} shows a comparison between simulation and analytical results for the Bernoulli model. We see that the theoretical and simulation curves match, which validates our model. Also, we see that for $\lambda_{\mathrm{E}} \to 0$ only regular traffic occurs and $\lambda_{\mathrm{E}} \to \infty$ implies that only alarm traffic is received at the BS. Three regions are identified, two saturation regions (when $\lambda_{\mathrm{E}} \to 0$ and $\lambda_{\mathrm{E}} \to \infty$) and a transition region.

\begin{figure}[t]
	\centering
		\includegraphics[width=0.75\linewidth]{rateAnaSimBern.pdf}
	\caption{Expected total rate for Bernoulli traffic.}
	\label{fig:rateAnaSimBern}
\end{figure}

\subsection{Markov Chain Model}\label{sub:MarkovchainModel}
The Markov chain model in Sec.~\ref{sec:MarkovchainAnalysis} is numerically evaluated in this subsection. We compare the total rate computed from the simulations against the approximation $\widetilde{R_{\mathrm{T}}}$ in~\eqref{eqn:totalRateApproxMarkovchain} and the analytical expression for $\overline{R_{\mathrm{T}}}$ in~\eqref{eqn:totalRateAnalytical}. We chose to include $\overline{R_{\mathrm{T}}}$ since we want to compare the two expressions and identify the numerical values of $q$ for which they are close.

In Fig.~\ref{fig:rateAnaSimBernMCvaryq} the expected total rate of the Markov chain model is shown for two values of $\lambda_E$. It can be seen that for the Bernoulli model, the rate is constant, since it does not depend on $q$. As for the Markov chain model, the rate obtained from the simulation is always upper bounded by the steady-state approximation, where the latter is obtained from~\eqref{eqn:totalRateApproxMarkovchain}. Further, these two curves have the same shape. The approximation can be used as an upper bound on the total rate at the BS; however the bound is not tight.

\begin{figure}[t]
	\centering
		\includegraphics[width=0.7\linewidth]{rateAnaSimBernMCvaryq.pdf}
	\caption{Expected total rates for Bernoulli traffic and for the Markov chain model; $\lambda_{\mathrm{M}} = 10^{-1}$.}
	\label{fig:rateAnaSimBernMCvaryq}
\end{figure}

\begin{figure}[t]
	\centering
		\includegraphics[width=0.7\linewidth]{autocorrelationE001M001.pdf}
	\caption{Sample ACF of the total rate for the Markov chain model; $\lambda_{\mathrm{E}} = 10^{-2}$, $\lambda_{\mathrm{M}} = 10^{-2}$.}
	\label{fig:autocovarianceE001M001}
\end{figure}

The sample autocovariance $\overline{C_{RR}}(k)$ is shown in Fig.~\ref{fig:autocovarianceE001M001}. Focusing first on the case $q=0.1$, we see that the ACF almost behaves like the one from an i.i.d. Bernoulli process, in that it has short memory. This is because the $p_\mathbf{x}$s are low (through the relatively low densities of the PPPs) and because of the relatively small value of $q$. Increasing the value of $q$, see the dashed red (for $q=0.5$) and solid black (for $q=0.9$) curves, increases the memory, i.e. the total rate at a given time $k$ is correlated with many past values. This is because the Markov chain now stays in the alarm state longer when it enters that state.

Hence, the introduction of the additional parameter $q$ in the Markov chain model allows for tuning the temporal correlation of the individual rate processes of the MTDs and, as a result, that of the total rate process.

\section{Conclusion and Future Work}\label{sec:Conclusion}
In this paper, a MTC traffic model based on spatial point processes was given. We also provided a verification of the model via simulations and derived an expression for the total rate of the devices. This expression is very fast to compute, compared to a full simulation, especially for high device and event densities. A Markov chain model was also defined. It was seen that approximating the probability $p_\mathbf{x}$ by $\overline{p}$ for all devices, gives a good approximation of the total rate for low values of $q$.
The parameter $q$ of the Markov chain model enables tuning of the model to suit various MTC applications and alarm reporting strategies. The models can be used to assess network performance in terms of the total rate and to see the impact of the event density. Furthermore, the Markov chain model, along with the tunable parameter $q$, can be used to study the impact of events on the temporal correlation of the total traffic at the BS.
Also, even though our model is a source model, the expected total rate is still fast to compute, thanks to the machinery of PPPs. As future work, we plan to include time-dependency in the event modeling, as well as to consider several types of MTDs and events. Also, we plan to model other types of sources, such as Poisson and periodic sources, and study the variance of the total traffic, along with its impact on network performance.

\section{Acknowledgements}\label{sec:Acknowledgements}
This work has been supported by the cooperative project VIRTUOSO, partially funded by Innovation Fund Denmark.

\bibliographystyle{ieeetr}

redpajama_set_name: RedPajamaArXiv


Judgment of the Court (Grand Chamber) of 21 February 2006. # Halifax plc, Leeds Permanent Development Services Ltd and County Wide Property Investments Ltd v Commissioners of Customs & Excise. # Reference for a preliminary ruling: VAT and Duties Tribunal, London - United Kingdom. # Sixth VAT Directive - Article 2(1), Article 4(1) and (2), Article 5(1) and Article 6(1) - Economic activity - Supplies of goods - Supplies of services - Abusive practice -Transactions designed solely to obtain a tax advantage. # Case C-255/02.
1. This reference for a preliminary ruling relates to the interpretation of Sixth Council Directive 77/388/EEC of 17 May 1977 on the harmonisation of the laws of the Member States relating to turnover taxes – Common system of value added tax: uniform basis of assessment (OJ 1977 L 145, p. 1), as amended by Council Directive 95/7/EC of 10 April 1995 (OJ 1995 L 102, p. 18, hereinafter 'the Sixth Directive').
2. The reference was made in proceedings brought by Halifax plc ('Halifax'), Leeds Permanent Development Services Ltd ('Leeds Development') and County Wide Property Investments Ltd ('County') against the Commissioners of Customs and Excise ('the Commissioners') in relation to the latter's rejection of applications for recovery of or relief from value added tax ('VAT') submitted by Leeds Development and County under a scheme designed to reduce the tax burden of the Halifax Plc Group.
3. Article 2(1) of the Sixth Directive provides that the supply of goods or services effected for consideration within the territory of the country by a taxable person acting as such is to be subject to VAT.
4. Under Article 4(1) of the Sixth Directive, 'taxable person' means any person who independently carries out any economic activity specified in paragraph 2 of that article. 'Economic activities' are defined in Article 4(2) as comprising all activities of producers, traders and persons supplying services, including the exploitation of tangible or intangible property for the purpose of obtaining income therefrom on a continuing basis.
5. Article 5(1) of the Sixth Directive states that '"supply of goods" means the transfer of the right to dispose of tangible property as owner'.
6. Article 6(1) of the Sixth Directive provides that '"supply of services" means any transaction which does not constitute a supply of goods within the meaning of Article 5'.
7. Under Article 13B(b) of the Sixth Directive, the Member States are required, subject to certain exceptions listed there, to exempt the leasing or letting of immovable property. However, under Article 13C(a) Member States may allow taxpayers a right of option for taxation in respect of such transactions.
8. Article 13B(d) of the Sixth Directive states that the Member States are to exempt from VAT certain activities in the financial services sector.
10. As regards goods and services to be used by a taxable person both for transactions in respect of which VAT is deductible and for transactions in respect of which it is not, the first subparagraph of Article 17(5) of the Sixth Directive states that 'only such proportion of the value added tax shall be deductible as is attributable to the former transactions'.
11. According to the second subparagraph of that provision, '[t]his proportion shall be determined, in accordance with Article 19, for all the transactions carried out by the taxable person'.
12. Halifax is a banking company. The vast majority of its services are exempt from VAT. At the material time, it was able to recover less than 5% of its input VAT.
13. According to the observations submitted by Halifax, Leeds Development is a property development company and County is a property development and investment company.
14. It appears from the order for reference that Leeds Development and County, and another member of the Halifax Plc Group involved in the transactions at issue, Halifax Property Investments Ltd (hereinafter 'Property'), are each wholly owned subsidiaries of Halifax. Leeds Development and County are each registered separately for VAT, and Property is unregistered.
15. For the purposes of its business, Halifax needed to construct call centres on four different sites at Cromac Wood and at Dundonald in Northern Ireland, at Livingston in Scotland and at West Bank, Leeds, in the North-East of England, on which it held a lease with about 125 years to run or the freehold or a fee simple interest.
16. On 17 December 1999, Halifax initially contracted with Cusp Ltd, an arm's length property development and contracting company, for the development of the Cromac Wood site. By a novation agreement of 28 February 2000, Halifax then disengaged itself from that contract and its rights and obligations became those of County.
17. Between 29 February and 6 April 2000, Halifax, Leeds Development, County and Property entered into a number of agreements relating to the various sites. The order for reference shows that the transactions for each of the sites followed a similar course.
18. As regards the sites at Cromac Wood, Dundonald and Livingston, on 29 February 2000 Halifax entered into loan agreements with Leeds Development, under which it agreed to lend it sufficient amounts for Leeds Development to acquire an interest in and develop the sites, for a maximum total amount of GBP 59 million.
19. Halifax and Leeds Development also entered into an agreement for the carrying out of certain construction works on the sites. For those works, Leeds Development was paid a little over GBP 120 000 by Halifax, including VAT of almost GBP 20 000, and Leeds Development issued three receipted VAT invoices to Halifax for that amount. Halifax also entered into an agreement with Leeds Development to grant leases of the sites to the latter at a premium, each for a term of 20 years, with the lessee having an option to extend the term to 99 years.
20. On 29 February 2000, Leeds Development also entered into a development and funding agreement with County, under which the latter was to carry out or procure the carrying out of construction work on the Cromac Wood, Dundonald and Livingston sites, including the works which Leeds Development had agreed to carry out or procure under the agreement between it and Halifax.
21. On the same date, Halifax made the initial advances to Leeds Development under the loans together with payment for the works, amounting in all to GBP 44 815 000. That sum was paid into a bank account which was dealt with at the direction of Leeds Development. The latter instructed that an identical sum, including VAT of more than GBP 6 600 000, be paid to County by way of an advance payment for the works carried out or procured by the latter. That transaction was confirmed on the same day by the bank concerned and the funds were then placed on overnight deposit. On the same date, County issued a receipted VAT invoice to Leeds Development.
22. 29 February 2000 was also the last day of Leeds Development's February 2000 accounting period. It submitted a return claiming recovery of VAT of almost GBP 6 700 000.
23. On 1 March 2000, the sum of GBP 44 815 000, plus accrued interest, was transferred to an account opened in County's name at another bank.
24. On 6 April 2000, pursuant to the agreement of 29 February 2000, Halifax granted to Leeds Development leases of the three sites at Cromac Wood, Dundonald and Livingston in exchange for premiums totalling around GBP 7 400 000, with each lease being treated as an exempt supply for VAT purposes. Each premium was funded by Leeds Development by a further drawdown under the initial loan agreements.
25. On the same date, Leeds Development also entered into an agreement to assign each of those leases to Property for a premium, with completion of each assignment to take place on the first working day after completion of the works and each being regarded as a VAT-exempt transaction. The premium was to be calculated by reference to a formula such that it was expected that Leeds Development would generate a total profit of GBP 180 000. Property in turn entered into agreements to under-let premises at Cromac Wood, Dundonald and Livingston to Halifax for a premium, in each case to be calculated by reference to the price paid by Property to Leeds Development for the assignment of the respective lease, plus a profit. The profit to be achieved by Property from those under-letting arrangements was expected to be GBP 85 000.
26. With respect to the Leeds West Bank site, on 13 March 2000 Halifax and Leeds Development concluded a loan agreement and an agreement for a lease and also an agreement for works. Halifax paid the sum of GBP 41 900, including a little over GBP 6 000 VAT, in relation to the initial works carried out and Leeds Development issued a receipted VAT invoice for the full amount. Halifax made a first advance of funds to Leeds Development of around GBP 3 000 000 under the loan agreement.
27. On the same day, Leeds Development and County entered into a development and funding agreement. Leeds Development made a prepayment to County, which issued receipted VAT invoices in relation to the works carried out under that agreement for over GBP 3 000 000, including VAT of about GBP 455 000. In its return for the March 2000 accounting period, Leeds Development claimed recovery of around GBP 455 000 input VAT.
28. On 6 April 2000, Halifax granted to Leeds Development the lease of the West Bank site and an agreement was entered into for the assignment of that lease by Leeds Development, for a premium, to Property. By a separate agreement, Property undertook to grant an underlease to Halifax.
29. In order to carry out the works under the various agreements entered into with Leeds Development, County engaged independent main contractors and professionals ('the arm's-length builders') for each of the sites. It appears that agreements were entered into with the independent contractors by stages and that those agreements were accompanied by separate agreements to which Halifax was a party. Those agreements gave warranties to Halifax relating inter alia to the carrying out by the arm's-length builder concerned of its duties and obligations.
– Halifax could deduct the deductible proportion of input VAT on the works to be carried out under the agreements for works entered into with Leeds Development.
– Leeds Development could deduct for the February 2000 period the VAT shown on the County invoice of 29 February 2000, totalling more than GBP 6 600 000 and, for the March 2000 period, the VAT shown on the invoice of 13 March 2000 of about GBP 455 000.
– County would account for all the output VAT shown on those invoices and could deduct the input VAT paid for the works carried out by the arm's length builders.
– The agreements entered into by Leeds Development of 6 April 2000 in relation to the assignment to Property of the leases of the four sites would be exempt transactions. As they took place in a different year, those supplies would not cause any adjustments to Leeds Development' input tax recovery position for the February and March 2000 accounting periods, which fell within the year ending on 31 March 2000.
– the property interests of Leeds Development in the sites had to be designed so that they did not rank as capital items. Otherwise the transfer of those rights to Property would affect the former's rights of deduction.
32. By decisions of 4 and 7 July 2000, the Commissioners refused Leeds Development's claims for deduction and those of County in relation to the VAT charged to it by the arm's-length builders.
– Leeds Development made no supplies of works to Halifax, nor did it obtain supplies of construction works from County – those transactions accordingly did not fall to be taken into account for VAT purposes.
– On a proper analysis of the arrangements as a whole, Halifax received supplies from the arm's-length builders and not from Leeds Development. Halifax could therefore deduct the VAT on those works, applying its normal recovery percentage.
34. Halifax, Leeds Development and County appealed against the Commissioners' decisions before the VAT and Duties Tribunal London, London. Halifax claimed that those decisions operate so as to treat it as having received taxable supplies of construction services, which should have been treated as supplies to County. Leeds Development and County contended that those decisions operated so as to disallow their claims for recovery of or relief from input VAT.
35. Halifax, Leeds Development and County submitted that all the transactions forming part of the arrangements with which their action was concerned were genuine. Not only did the supplies of goods and services by the arm's-length builders serve commercial purposes, but so also did the supplies of construction services by County and the supplies of construction services and land by Leeds Development. Each of those two companies and Property were to earn profits from their participation in those arrangements. Although the arrangements had been structured so as to achieve an advantageous fiscal result, the VAT system imposed a charge to tax on a transaction-by-transaction basis.
36. The Commissioners' first submission was that a transaction entered into solely for the purpose of VAT avoidance was neither itself a 'supply', nor a step taken in the course or furtherance of an 'economic activity' as those terms in the Sixth Directive are properly to be interpreted. The application of that principle of interpretation to the arrangements at issue meant that the undertakings of Leeds Development to Halifax did not count as 'supplies'; nor did the undertakings of County to Leeds Development.
37. The Commissioners' second submission was that transactions entered into solely for the purpose of VAT avoidance should, in accordance with the general principle of Community law preventing 'abuse of rights', be disregarded and the terms of the Sixth Directive be applied to the true nature of the transactions at issue. However those arrangements were viewed, only the arm's length builders actually supplied construction services, and those supplies were made directly to Halifax.
38. By decision of 5 July 2001, the VAT and Duties Tribunal dismissed the appeals.
39. Halifax, Leeds Development and County appealed to the High Court of Justice England and Wales, Chancery Division, which quashed that decision and remitted the matter to the VAT and Duties Tribunal.
40. The referring tribunal states that, in its original decision; of 5 July 2001, it had relied on an interpretation of Article 4(2) of the Sixth Directive according to which regard had to be had to the objective characteristics of the transactions in determining that the transactions in question were not supplies for VAT purposes. It considers that the interpretation of that provision should now be referred to the Court.
42. In that regard, the referring tribunal states that the evidence given by the directors of Halifax, Leeds Development and County shows that the sole purpose of the two latter companies in entering into the transactions concerned was the avoidance of VAT. In other words, it was the intention of Halifax, Leeds Development and County to obtain a tax advantage through the implementation of an artificial tax avoidance scheme. The referring tribunal mentions Case C-110/99 Emsland Stärke  ECR I-11569, paragraph 53.
qualify for VAT purposes as supplies made by or to the participators in the course of their economic activities?
(b) In the relevant circumstances, what factors should be considered in determining the identity of the recipients of the supplies made by the arm's-length builders?
44. By question 1(a), the referring tribunal seeks essentially to ascertain whether transactions of the kind at issue in the main proceedings constitute supplies of goods or supplies of services and an economic activity within the meaning of Article 2(1), Article 4(1) and (2), Article 5(1) and Article 6(1) of the Sixth Directive, when they are effected for the sole purpose of obtaining a tax advantage, without any other economic aim.
45. Halifax, Leeds Development and County submit that, under the scheme of the Sixth Directive, operations that have been carried out with the sole purpose of obtaining a tax advantage and without pursuing any independent economic objective are, for VAT purposes, supplies of goods or services made by the participants or for their benefit in the context of their economic activities.
46. The United Kingdom and Ireland submit that transactions which, first, are carried out by each participant solely in order to obtain a tax advantage and, second, do not pursue any independent economic objective, are not supplies of goods or services in the context of their economic activities.
47. The Commission considers that the purpose for which a transaction is carried out is irrelevant for the purposes of Article 2 of the Sixth Directive.
48. It must be remembered first of all that the Sixth Directive establishes a common system of VAT based, inter alia, on a uniform definition of taxable transactions (see, in particular, Case C-305/01 MGK-Kraftfahrzeuge-Factoring  ECR I-6729, paragraph 38).
49. In that regard, under the Sixth Directive the scope of VAT is very wide in that Article 2 thereof, which concerns taxable transactions, refers not only to imports of goods but also to the supply of goods or services effected for consideration within the territory of the country by a taxable person acting as such.
50. As regards, first, the term 'supply of goods', Article 5(1) of the Sixth Directive states that any transfer of the right to dispose of tangible property as owner constitutes such a supply.
51. It is clear from the case-law of the Court that that term covers any transfer of tangible property by one party who empowers the other party actually to dispose of it as if he were the owner of the property (see, in particular, Case C-320/88 Shipping and Forwarding Enterprise Safe  ECR I-285, paragraph 7, and Case C-25/03 HE  ECR I-3123, paragraph 64).
52. As regards the term 'supply of services', it is clear from Article 6(1) of the Sixth Directive that it covers all transactions not constituting a supply of goods within the meaning of Article 5 of that directive.
53. Next, according to Article 4(1) of the Sixth Directive, any person who independently carries out any economic activity, whatever the purpose or results of that activity, is regarded as a taxable person.
54. Finally, the term 'economic activity' is defined in Article 4(2) of the Sixth Directive as comprising 'all' activities of producers, traders and persons supplying services, and, according to the case-law, it includes all stages of production, distribution and the provision of services (see, in particular, Case C-186/89 Van Tiem  ECR I-4363, paragraph 17, and MGK-Kraftfahrzeuge-Factoring , paragraph 42).
55. As the Court held in paragraph 26 of its judgment in Case C-260/98 Commission v Greece  ECR I-6537, an analysis of the definitions of taxable person and economic activities shows that the scope of the term economic activities is very wide, and that the term is objective in character, in the sense that the activity is considered per se and without regard to its purpose or results (see also Case 235/85 Commission v Netherlands  ECR 1471, paragraph 8, and, to that effect, in particular Case 268/83 Rompelman  ECR 655, paragraph 19, and Case C-497/01 Zita Modes  ECR I-14393, paragraph 38).
56. That analysis and that of the terms 'supply of goods' and 'supply of services' show that those terms, which define taxable transactions under the Sixth Directive, are all objective in nature and apply without regard to the purpose or results of the transactions concerned (see, to that effect, Joined Cases C-354/03, C-355/03 and C-484/03 Optigen and Others  ECR I-0000, paragraph 44).
57. As the Court held in paragraph 24 of its judgment in Case C-4/94 BLP Group  ECR I-983, an obligation on the tax authorities to carry out inquiries to determine the intention of the taxable person would be contrary to the objectives of the common system of VAT of ensuring legal certainty and facilitating the application of VAT by having regard, save in exceptional cases, to the objective character of the transaction in question.
58. It follows that transactions of the kind at issue in the main proceedings are supplies of goods or services and an economic activity within the meaning of Article 2(1), Article 4(1) and (2), Article 5(1) and Article 6(1) of the Sixth Directive, provided that they satisfy the objective criteria on which those concepts are based.
59. It is true that those criteria are not satisfied where tax is evaded, for example by means of untruthful tax returns or the issue of improper invoices. The fact nevertheless remains that the question whether a given transaction is carried out for the sole purpose of obtaining a tax advantage is entirely irrelevant in determining whether it constitutes a supply of goods or services and an economic activity.
60. It follows that the answer to Question 1(a) must be that transactions of the kind at issue in the main proceedings constitute supplies of goods or services and an economic activity within the meaning of Article 2(1), Article 4(1) and (2), Article 5(1) and Article 6(1) of the Sixth Directive, provided that they satisfy the objective criteria on which those concepts are based, even if they are carried out with the sole aim of obtaining a tax advantage, without any other economic objective.
61. By Question 2, which it is appropriate to consider before Question 1(b), the national tribunal seeks essentially to ascertain whether the Sixth Directive must be interpreted as meaning that a taxable person has no right to deduct input VAT where the transactions on which that right is based constitute an abusive practice.
62. Halifax, Leeds Development and County consider that, in the context of the VAT system, Community law does not contain any theory of abuse of rights which the tax authorities of a Member State can invoke against individuals in order to reject their applications for recovery or deduction of input tax.
63. The United Kingdom Government considers that the principle of abuse of rights is a general principle of Community law and prevents a taxable person from deducting VAT under Article 17 of the Sixth Directive and any applicable national legislation implementing that article where it is apparent from the application for deduction that the objectives of VAT, laid down by the Sixth Directive, are not being attained and that the taxable person is artificially creating conditions to justify the application for deduction.
64. The French Government submits that Community law, in so far as it allows a Member State to take measures to ensure that none of its nationals can abusively or fraudulently exploit Community provisions by taking advantage of the possibilities made available by virtue of the EC Treaty, does not preclude a Member State from withholding a right of deduction from a taxable person or a group of taxable persons having links with one another, who have undertaken purely artificial transactions for the sole purpose of obtaining an improper refund of VAT.
65. Ireland considers that the principle of abuse of rights, as developed by the Court, enables the tax authorities to reject taxable persons' applications for recovery or deduction of input VAT paid on transactions such as those at issue in the main proceedings.
66. The Commission is of the opinion that where a taxable person or a group of taxable persons having links with one another engage in a series of transactions which, taken together, give rise to an artificial situation motivated solely by the aim to create the conditions necessary for the recovery of input VAT, those transactions should be disregarded.
67. As a preliminary point, it must be noted that the problems raised by the questions submitted by the VAT and Duties Tribunal appear, at least in part, to stem from national rules which allow a taxable person who undertakes at the same time taxed and untaxed transactions, or only untaxed transactions, to transfer leases of immovable property to another entity under its control, which is entitled to opt for taxation of the letting of that property and thereby to deduct the total input VAT paid on construction or renovation costs.
68. Notwithstanding that finding, it must be borne in mind that, according to settled case-law, Community law cannot be relied on for abusive or fraudulent ends (see, in particular Case C-367/96 Kefalas and Others  ECR I-2843, paragraph 20; Case C-373/97 Diamantis  ECR I-1705, paragraph 33; and Case C-32/03 Fini H  ECR I-1599, paragraph 32).
69. The application of Community legislation cannot be extended to cover abusive practices by economic operators, that is to say transactions carried out not in the context of normal commercial operations, but solely for the purpose of wrongfully obtaining advantages provided for by Community law (see, to that effect, Case 125/76 Cremer  ECR 1593, paragraph 21; Case C-8/92 General Milk Products  ECR I-779, paragraph 21; and Emsland-Stärke , paragraph 51).
70. That principle of prohibiting abusive practices also applies to the sphere of VAT.
71. Preventing possible tax evasion, avoidance and abuse is an objective recognised and encouraged by the Sixth Directive (see Joined Cases C-487/01 and C-7/02 Gemeente Leusden and Holin Groep  ECR I-5337, paragraph 76).
72. However, as the Court has held on numerous occasions, Community legislation must be certain and its application foreseeable by those subject to it (see, in particular, Case C-301/97 Netherlands v Council  ECR I-8853, paragraph 43). That requirement of legal certainty must be observed all the more strictly in the case of rules liable to entail financial consequences, in order that those concerned may know precisely the extent of the obligations which they impose on them (Case 326/85 Netherlands v Commission  ECR 5091, paragraph 24, and Case C-17/01 Sudholz  ECR I-4243, paragraph 34).
73. Moreover, it is clear from the case-law that a trader's choice between exempt transactions and taxable transactions may be based on a range of factors, including tax considerations relating to the VAT system (see, in particular, BLP Group , paragraph 26, and Case C-108/99 Cantor Fitzgerald International  ECR I-7257, paragraph 33). Where the taxable person chooses one of two transactions, the Sixth Directive does not require him to choose the one which involves paying the highest amount of VAT. On the contrary, as the Advocate General observed in point 85 of his Opinion, taxpayers may choose to structure their business so as to limit their tax liability.
74. In view of the foregoing considerations, it would appear that, in the sphere of VAT, an abusive practice can be found to exist only if, first, the transactions concerned, notwithstanding formal application of the conditions laid down by the relevant provisions of the Sixth Directive and the national legislation transposing it, result in the accrual of a tax advantage the grant of which would be contrary to the purpose of those provisions.
75. Second, it must also be apparent from a number of objective factors that the essential aim of the transactions concerned is to obtain a tax advantage. As the Advocate General observed in point 89 of his Opinion, the prohibition of abuse is not relevant where the economic activity carried out may have some explanation other than the mere attainment of tax advantages.
76. It is for the national court to verify in accordance with the rules of evidence of national law, provided that the effectiveness of Community law is not undermined, whether action constituting such an abusive practice has taken place in the case before it (see Case C-515/03 Eichsfelder Schalchtbetrieb  ECR I-0000, paragraph 40).
77. However, the Court, when giving a preliminary ruling, may, where appropriate, provide clarification designed to give the national court guidance in its interpretation (see, in particular, Case C-79/01 Payroll and Others  ECR I-8923, paragraph 29).
78. In that connection, it must be borne in mind that the deduction system under the Sixth Directive is meant to relieve the trader entirely of the burden of the VAT payable or paid in the course of all his economic activities. The common system of VAT consequently ensures complete neutrality of taxation of all economic activities, whatever their purpose or results, provided that they are themselves subject in principle to VAT (see, in particular, Case C-408/98 Abbey National  ECR I-1361, paragraph 24, and Zita Modes , paragraph 38).
79. According to settled case-law, Article 2 of First Council Directive 67/227/EEC of 11 April 1967 on the harmonisation of legislation of Member States concerning turnover taxes (OJ, English Special Edition 1967, p. 14) and Article 17(2), (3) and (5) of the Sixth Directive must be interpreted as meaning that, in principle, the existence of a direct and immediate link between a particular input transaction and a particular output transaction or transactions giving rise to entitlement to deduct is necessary before the taxable person is entitled to deduct input VAT and in order to determine the extent of such entitlement (Case C-98/98 Midland Bank  ECR I-4177, paragraph 24; Abbey National , paragraph 26; and Case C-16/00 Cibo Participations  ECR I-6663, paragraph 29).
80. To allow taxable persons to deduct all input VAT even though, in the context of their normal commercial operations, no transactions conforming with the deduction rules of the Sixth Directive or of the national legislation transposing it would have enabled them to deduct such VAT, or would have allowed them to deduct only a part, would be contrary to the principle of fiscal neutrality and, therefore, contrary to the purpose of those rules.
81. As regards the second element, whereby the transactions concerned must essentially seek to obtain a tax advantage, it must be borne in mind that it is the responsibility of the national court to determine the real substance and significance of the transactions concerned. In so doing, it may take account of the purely artificial nature of those transactions and the links of a legal, economic and/or personal nature between the operators involved in the scheme for reduction of the tax burden (see, to that effect, Emsland Stärke , paragraph 58).
82. In any event, it is clear from the order for reference that the VAT and Duties Tribunal considers that the sole purpose of the transactions at issue in the main proceedings was to obtain a tax advantage.
83. Finally, it must be borne in mind that the right of deduction provided for in Article 17 et seq. of the Sixth Directive is an integral part of the VAT scheme and in principle may not be limited. It must be exercised immediately in respect of all the taxes charged on transactions relating to inputs (see, in particular, Case C-62/93 BP Supergas  ECR I-1883, paragraph 18, and Joined Cases C-110/98 to C‑147/98 Gabalfrisa and Others  ECR I-1577, paragraph 43).
84. However, as the Court has already had occasion to observe, it is only in the absence of fraud or abuse, and subject to adjustments which may be made in accordance with the conditions laid down in Article 20 of the Sixth Directive, that the right to deduct, once it has arisen, is retained (see, in particular, Case C-400/98 Breitshol  ECR I-4321, paragraph 41, and Case C-396/98 Schlossstraße  ECR I-4279, paragraph 42).
85. Accordingly, the answer to be given to the second question must be that the Sixth Directive must be interpreted as precluding any right of a taxable person to deduct input VAT where the transactions from which that right derives constitute an abusive practice.
86. For it to be found that an abusive practice exists, it is necessary, first, that the transactions concerned, notwithstanding formal application of the conditions laid down by the relevant provisions of the Sixth Directive and of national legislation transposing it, result in the accrual of a tax advantage the grant of which would be contrary to the purpose of those provisions. Second, it must also be apparent from a number of objective factors that the essential aim of the transactions concerned is to obtain a tax advantage.
87. In view of the answers given to Question 1(a) and Question 2, Question 1(b) must be taken to mean that the national court seeks, essentially, to ascertain under what conditions VAT may be recovered where an abusive practice has been found to exist.
88. The United Kingdom Government considers that it is necessary to examine the factors which demonstrate the true economic basis of the transactions and to determine whether or not the purposes of the Sixth Directive have been attained.
(e) neither County nor Leeds Development had any property interests of substance.
Those factors prompt the conclusion that Halifax is the recipient of the supply made by the arm's-length builders and thus give rise to a result that achieves the purpose of the Sixth Directive.
90. It must be noted at the outset that no provision of the Sixth Directive deals with the recovery of VAT. That directive merely defines, in Article 20, the conditions which must be complied with in order that deduction of input taxes may be adjusted at the level of the person to whom goods or services have been provided (see the order of 3 March 2004 in Case C-395/02 Transport Service  ECR I-1991, paragraph 27).
91. It is therefore, as a rule, for the Member States to lay down the conditions under which the tax authorities may recover VAT after the event, while remaining within the limits imposed by Community law ( Transport Service , paragraph 28).
92. It is important, however, to note in that respect that the measures which the Member States may adopt under Article 22(8) of the Sixth Directive in order to ensure the correct levying and collection of the tax and for the prevention of fraud must not go further than is necessary to attain such objectives (see Gabalfrisa and Others, paragraph 52, and the order in Transport Service , paragraph 29). They may not therefore be used in such a way that they would have the effect of undermining the neutrality of VAT, which is a fundamental principle of the common system of VAT established by the relevant Community legislation (see Case C-454/98 Schmeink & Cofreth and Strobel  ECR I-6973, paragraph 59).
93. It must also be borne in mind that a finding of abusive practice must not lead to a penalty, for which a clear and unambiguous legal basis would be necessary, but rather to an obligation to repay, simply as a consequence of that finding, which rendered undue all or part of the deductions of input VAT (see, to that effect, Emsland Stärke , paragraph 56).
94. It follows that transactions involved in an abusive practice must be redefined so as to re-establish the situation that would have prevailed in the absence of the transactions constituting that abusive practice.
95. In that regard, the tax authorities are entitled to demand, with retroactive effect, repayment of the amounts deducted in relation to each transaction whenever they find that the right to deduct has been exercised abusively ( Fini H , paragraph 33).
96. However, they must also subtract therefrom any tax charged on an output transaction for which the taxable person was artificially liable under a scheme for reduction of the tax burden and, if appropriate, they must reimburse any excess.
97. Similarly, it must allow a taxable person who, in the absence of transactions constituting an abusive practice, would have benefited from the first transaction not constituting such a practice, to deduct, under the deduction rules of the Sixth Directive, the VAT on that input transaction.
98. It follows that the answer to Question 1(b) must be that, where an abusive practice has been found to exist, the transactions involved must be redefined so as to re-establish the situation that would have prevailed in the absence of the transactions constituting that abusive practice.
99. Since these proceedings are, for the parties to the main proceedings, a step in the action pending before the national tribunal, the decision on costs is a matter for that tribunal. Costs incurred in submitting observations to the Court, other than those the costs of those parties, are not recoverable.
1. Transactions of the kind at issue in the main proceedings constitute supplies of goods or services and an economic activity within the meaning of Article 2(1), Article 4(1) and (2), Article 5(1) and Article 6(1) of Sixth Council Directive 77/388/EEC of 17 May 1977 on the harmonisation of the laws of the Member States relating to turnover taxes – Common system of value added tax: uniform basis of assessment, as amended by Council Directive 95/7/EC of 10 April 1995, provided that they satisfy the objective criteria on which those concepts are based, even if they are carried out with the sole aim of obtaining a tax advantage, without any other economic objective.
2. The Sixth Directive must be interpreted as precluding any right of a taxable person to deduct input VAT where the transactions from which that right derives constitute an abusive practice.
For it to be found that an abusive practice exists, it is necessary, first, that the transactions concerned, notwithstanding formal application of the conditions laid down by the relevant provisions of the Sixth Directive and of national legislation transposing it, result in the accrual of a tax advantage the grant of which would be contrary to the purpose of those provisions. Second, it must also be apparent from a number of objective factors that the essential aim of the transactions concerned is to obtain a tax advantage.
3. Where an abusive practice has been found to exist, the transactions involved must be redefined so as to re-establish the situation that would have prevailed in the absence of the transactions constituting that abusive practice.


text:
Q: Express application not responding to outside traffic I have a webservice (private-bower) that listen on port 5678 on a remote ubuntu machine.
netstats:
tcp        0      0 0.0.0.0:5678            0.0.0.0:*               LISTEN      10605/node

I don't have any rules in my iptables and the ufw status is inactive.
I get a response by doing $curl ip:5678 only within my remote machine, but when I do it on my local one, I receive no response what so ever.
The remote ip is pingable from my local machine btw.
I didn't write that webservice, here's the line where it starts to listen:
var server = app.listen(_config.port, function() {
    logger.log('Bower server started on port ' + _config.port);
});

How can I let external ip address to make request on that port?
thanks!

A: app.listen by default listens on localhost, you can pass in a different bind address as the second argument as described in docs. as I understand it: 0.0.0.0 represents 'all available interfaces' and localhost represents 'only loopback interface'
var server = app.listen(_config.port, '0.0.0.0', function() {
    logger.log('Bower server started on port ' + _config.port);
});

redpajama_set_name: RedPajamaStackExchange


Are you obsessed with sushi but want to learn how you can DIY? Well, believe it or not, sushi isn't too hard to make. To start off, all you will need is sushi rice, nori sheets (seaweed), which can be found in most supermarkets, and a bamboo mat, which you can conveniently buy on Amazon.
You cannot use any old rice to make sushi. You have to make the rice using rice vinegar and sugar so your sushi roll doesn't fall apart.
Combine 3 cups of water and 2 cups of uncooked white rice in a medium saucepan. Bring to a boil and reduce the heat to low. Cover the pan and let the rice cook for about 20 minutes.
While the rice is cooking, combine 1/2 cup of rice vinegar, 1 tablespoon of vegetable oil, 1/4 of white sugar and a pinch of salt in a small saucepan. Cook over medium heat until the sugar completely dissolves.
Cool the rice vinegar/sugar mixture for a few minutes (do not refrigerate – the mixture will harden) and mix it into the cooked rice. The rice will dry as it cools.
Before you begin making sushi, you must master the art of rolling sushi, which isn't difficult at all, especially if you are using a bamboo mat.
First, you place plastic wrap on top of the bamboo mat. This will help protect your mat from the rice and ingredients so you can reuse it again.
Then you place a sheet of nori on the mat, with the shiny side facing down and the rough side facing upward.
Wet your fingers with water; this will making the rolling process easier.
Next, you spread a thin layer of cooked rice on top of the nori. Make sure you leave space at the top and bottom of the sheet.
Now, this is where you can be creative. You place the ingredients you want to use in the center of the nori sheet.
It is time to get rolling! Start by placing your thumbs underneath the mat and lift the edge up, and gently place it over the filling in the center.
Gently, press the "log" so the filling comes together and doesn't become loose and fall out.
Next, gently pull the edge of the mat toward you and fold it underneath your hands. Then, roll your sushi away from you until you reach the edge of the nori sheet.
Finally, lightly dampen the top border of the roll with water to seal it. Congratulations, you are done rolling the sushi!
Do you have a DIY sushi recipe you want to share? Share with a comment below!


text:
Guilty pleas in Cuba spying case
Submitted by: admin
A psychology professor and his wife pleaded guilty Tuesday to reduced federal charges in a case involving allegations that both had spied for the Cuban government for decades.
Carlos Alvarez, 61, pleaded guilty to conspiracy to become an unregistered foreign agent. His 56-year-old wife, Elsa Alvarez, admitted knowing about her husband's illegal activities but failing to report them to authorities.
Carlos Alvarez faces up to five years in prison and his wife up to three years on the revised charges. Both were charged previously with the more serious charge of acting as illegal Cuban agents, which carries a longer possible prison sentence.
U.S. District Judge K. Michael Moore set sentencing for Feb. 27.
Carlos Alvarez, a professor at Florida International University, was accused of spying for decades on Cuban-American exile groups and prominent individuals in Miami, as well as reporting on U.S. political affairs. His wife, also a university employee, was implicated to a lesser degree in the alleged spying.
The couple's arrests in January followed years of FBI surveillance, which included placing a listening device in the bedroom of their Miami home and wiretaps on their telephone. The FBI said Carlos Alvarez, known to the Cubans by the code name "David," used a short-wave radio and encryption techniques to communicate with his Cuban handlers.
Carlos Alvarez's lawyer, Steve Chaykin, said his client was never a Cuban intelligence agent and is not a supporter of Castro.
"His involvement with the Cuban intelligence agency was the result of idealism and naivete," Chaykin said.
Jane Moscowitz, attorney for Elsa Alvarez, said her client played a far lesser role. "Her offense is being a wife," Moscowitz said.
U.S. Attorney R. Alexander Acosta called the case "a stark reminder that there are among us some who, while enjoying the freedom and liberty our great nation offers, continue to serve the interests of another master."
The guilty pleas came after a federal judge last month upheld as evidence a lengthy statement Carlos Alvarez gave to the FBI in 2005. Alvarez admitted in those interviews he was a "collaborator" with Cuba's intelligence service beginning in 1977, but insisted he was mainly interested in opening dialogue with the communist government.
Carlos Alvarez's attorneys unsuccessfully tried to have that confession thrown out, contending that he was coerced into submitting to the FBI interviews and that he was promised immunity for prosecution if he cooperated. FBI agents admitted during hearings this summer that their goal was to recruit Carlos Alvarez as a double agent.
One conversation captured by the bedroom bug has Carlos Alvarez expressing relief to his wife that he'd told the FBI about his Cuban activities.
"Right now, for me, it was a relief that I was able to cooperate. It's been hell. It's been hell. I really saw it as a huge confession. It was an opportunity for me to confess what I've done wrong," he told his wife, according to government transcripts.
Carlos Alvarez has been jailed without bail since his arrest 11 months ago. Elsa Alvarez is free on $400,000 bail.
Source: Chron.com

redpajama_set_name: RedPajamaCommonCrawl


text:
January 31, 2017 Darby Bodden
I was sitting on a flight between New York and Zurich when we ran into some very light turbulence. It wasn't the kind where your neighbor who doesn't like to fly gets a death grip on their armrest; most people stayed asleep, but the flight attendants still hurried to their seats. Curious, I checked the in-flight channel. We'd lost a couple thousand feet in a minute or two. I laughed out loud because most of the passengers didn't have a clue.
I was a pilot. I don't fly anymore, except as a passenger. On my first tour, I had three other helicopters crash in my squadron, with the crews killed or permanently injured, and almost died or crashed eight times. Of the times I experienced, one was due to enemy fire, one was almost due to friendly/neutral fire, and the rest were accidents. I did the math, considered myself lucky, and did my next deployment on the ground.
Everyone's combat experience is different. I can't speak for anyone else. I'm proud of the discomfort we experienced. I pulled a trigger and called in airstrikes; getting shot would have been fair play, though I successfully did my level best to avoid it. Another officer and I (and a squad of Marines) walked into an enemy controlled village in the middle of the night to meet an elder who never showed up. I had dysentery once. Corpsman gave me Cipro when I finally went to medical after several days of constant fluidity. I thought it was funny then, and I still think it's funny now. Dying for no reason, to no gain, not to save someone's life or in a measured gamble to win against a clever foe, but because I got a bad roll of the dice or stepped in the wrong place? Hard pass.
I finished my deployments, finished my commitment, got out, kept the stories, no regrets, I'd do it all again. But I was edgy. I called in a suspicious package, my first year in New York. When I took a walk through one of the less opulent neighborhoods of Geneva at night, I did my best to project "hard target" and people crossed the street to avoid me. I don't attack people who startle me, but I could. I don't take cover when a firecracker goes off, but I figure out where the sound came from, just in case. I plan to live a long time.
In April of 2012 (I think, I'm terrible with calendars), I went back to Monaco, where I grew up, for the first time in 10 years. Monaco's a funny place. One family is responsible for making sure all the real estate is maintained and painted regularly. The police officers dress like Marines, even though they're not quite as sharp, and they're polite, multilingual, and everywhere. It's governed by the longest dynasty in the world, including Egyptian and Chinese rulers. The streets are clean*; the buses run on time. It's so predictable, I used the passive voice. Nothing happens in Monaco, not even accidents.
I was standing in a park on the side of the Rock, where the palace is. The gardens in Monaco are lovely and, like cops and surveillance, plentiful. But the smell hit me, the mix of the sea breeze and that particular combination of Mediterranean flora, the feel of the springy rubber of the playground under my feet where I'd run as a child over a decade back. New buildings had sprung up in other parts of the Principality, but this place was the same. Something inside me relaxed. I didn't feel the need to be watchful at all, and I thought, I'm standing at the precise point on Earth where the form of an idea has taken substance. I was safe. This was home.
*Even Monaco can't convince all the octogenarian heiresses to pick up after Mr. Ruffles, but it'll be pressure washed away by morning.
In Lifestyle Tags Flying, Roll D20, Mr. Ruffles


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text:
Sundays at 8 & 10 a.m. | Livestream at 10 a.m.
256 East Church Street, Jacksonville, FL 32202 · (904) 356-5507 · Give
St. John's Cathedral Jacksonville
From the Dean...
Livestream & Service Archives
Sunday Service Leaflets
Bishop Search
Bishop's Garden
Pledge 2022
Art in Taliaferro
The e-Eagle Newsletter
The Cathedral Quarterly
Choral Services and Music Events
The Great Organ
The Stanly and Claudia Gordon Music Endowment
The Baptismal Covenant: A Personal Approach
Podcast: Find it!
Center for Prayer & Spirituality
Grateful Gatherings - Wednesday Night
Green Spirits
Kindness Rocks Project
Ministry for Immigrants and Refugees
Worship Teams
Communications Requests
Event Scheduling Requests
The Great Organ
Historically, cathedrals are known for three important traditions. These have been called the "Chief Glories" over many centuries.
Masterful preaching, inspirational architecture and outstanding music are the three major areas peculiar to cathedrals. Certainly, these items are obvious in St. John's Cathedral.
The term "Great Organ" describes cathedral organs and has been used for centuries in most of the English Cathedrals as well as in Cathedrals in the Americas.
The first organ in St. John's was built by The Roosevelt Firm of New York in the 1880's.It was lost in the "Great Fire" in Jacksonville. The next instrument was built by Hook and Hastings of Boston, followed by a large Moller organ in 1949. Fifteen ranks of pipes were incorporated in the 1983 Austin organ. This stewardship was also included in the 2006 renovation and enlargement by Roger Colby Organ Company and Walker Technical Company. The organ presently includes 76 ranks of pipes and 46 digital ranks in the grand 4-manual (keyboard) console.
The cost of 1983 Austin Organ was $315,000.00. The major refurbishing of the main chancel organ in 2006, including a new console, new pipework, wind chest and re-voicing as well as the splendid West Organ cost $740,000.00.Replacement cost of the complete organ as of 2017 is estimated to be just over $2,000,000.00 according to the various builders.
Much work was done in the main organ located on both sides of the chancel in 2006 and a wonderful new organ situated on the Cathedral's West Wall. Who hasn't been impressed with The En Chamade Trumpet horizontally protruding from the West Organ!
The organ is ideal for the French School of organ performance as well as colorful support of the choir and the playing of J. S. Bach's Music. Leading the congregation in the singing of hymns and service music is perhaps the most important responsibility of the "Great Organ".
The organ was dedicated in February of 1984 with a program played by Christopher Dearnley of St. Paul's Cathedral, London. Mr. Dearnley also played for the royal wedding of Charles and Diana in 1981.St. John's was packed with close to 1,000 people overflowing into the vestibules and sacristy, people sitting on every available space of the floor and over 400 folks having to be turned away!
Since that time, we have hosted concerts with some of the leading organists in the world, two concerts with the Jacksonville Symphony as well as programs by local musicians.
Some of the guest artists included the organists of Westminster Abbey, St. Paul's, London, Gloucester Cathedral, York Minster, Riverside Church in New York, Yale University, Indiana University, the University of the South, the University of Florida and St. Thomas Church in New York.
The organ is presided over by Timothy Tuller, Canon for Music, who does a masterful job in presenting wonderful music on this noted organ.
A fund has been established, known as the Stanly and Claudia Gordon Music Endowment Fund, to benefit innovative programs produced by the music ministry and to provide for the time when major repairs will be required in the years ahead upon the Cathedral's organ. Friends and members of St. John's are encouraged to make contributions to this fund!
The care of the organ is entrusted to James Freeman and Associates, organ builders.
Canon for Music, Emeritus
Learn more about the Great Organ
R. A. Colby Organ Builders
Share this page: The Great Organ
St. John's Music
Jan 16 |
Offertory Anthem: Grow in grace
Jan 9 |
Offertory Anthem: O God, who by the leading of a star
Offertory Anthem: Of the Father's love begotten
Dec 19 |
Offertory Anthem: Magnificat (Service in E flat)
Hark! A thrilling voice is sounding
Copyright © 2022 St. John's Cathedral, Jacksonville, Florida
All Rights Reserved · Privacy Policy · Powered by Membership Vision
The Episcopal Church | Episcopal Diocese of Florida | Receive our Newsletter | The Lectionary Page
Livestream at 10 a.m.
Holy Eucharist 8 & 10 a.m.
256 East Church Street
Pledge Give Now Special Funds Altar Flowers
Your pledge helps us build community within and outside of the walls of the Cathedral. Over the years we have birthed several ministries that are now thriving nonprofits serving and educating in the Urban Core of Jacksonville and beyond.
Giving online? Click the "Give Online Now" button below to access our giving portal and select "Gen. Donation" for a one-time gift. You may also select "Pledge" to pay your pledge or any of the other funds listed to make a specific donation.
Giving by check? Make your check payable to St. John's Cathedral and mail to 256 E. Church St. Jacksonville, FL 32202
Have a question about giving? Please call our office (904) 356-5507
Give Online Now
Learn about the St. John's Cathedral Preservation Fund, the Cathedral Builders Fund and the Legacy Society.
Donate altar flowers in memory of someone or to commemorate a special day such as a birthday or anniversary. The suggested donation is $65.00 and should be sent to: St John's Cathedral, Attention: Accounting/Flower Donation, 256 East Church Street, Jacksonville, FL 32202. Please include the date that you would like the flowers on the altar and any words for the dedication when you send in your donation. Or donate onlinenow.
Thank you! Contact Teresa Mason for more information.


text:
<< Back to headlines 14/08/2019
Future of South Africa chrome mine unclear after Lanxess deal
Leather chemicals company Lanxess has confirmed that the proposed sale of its chrome chemicals business to Chinese manufacturer Brother Enterprises does not include the chrome mine it owns and runs in Rustenburg in South Africa.
Brother Enterprises will take over the Lanxess factory in the South African city of Newcastle as part of the proposed deal, which is subject to approval by the regulatory authorities. The Newcastle facility employs 220 people and makes sodium dichromate from chrome ore mined in Rustenburg.
Until 2024 at least, Lanxess will keep ownership of another factory in South Africa, located at Merebank, saying it will continue to make chrome tanning salts there under contract to Brother Enterprises.
However, in the formal announcement about the deal, which Lanxess made on August 12, it said nothing about Rustenburg. In response to a question about the future of the mine from leatherbiz, Lanxess said: "The chrome ore mine in Rustenburg is not part of the transaction with Brother Enterprises. We are considering strategic options for the mine at the moment."
Share this story: Facebook Twitter Google+ LinkedIn Pinterest
Third-largest chrome salts supplier makes Lanxess move
Major leather chemicals announcement from Lanxess
Lanxess predicts leather trends for spring-summer 21
Chrome-tanned leather loses its best defender
Lanxess unveils raft of products ahead of ACLE


text:
package com.capitalone.dashboard.collector;

import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertSame;
import static org.junit.Assert.assertTrue;
import static org.mockito.Matchers.eq;
import static org.mockito.Matchers.isA;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.ExecutionException;

import org.bson.types.ObjectId;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.runners.MockitoJUnitRunner;
import org.springframework.util.concurrent.ListenableFuture;

import com.capitalone.dashboard.model.FeatureCollector;
import com.capitalone.dashboard.model.Project;
import com.capitalone.dashboard.model.UpdateResult;
import com.capitalone.dashboard.repository.FeatureCollectorRepository;

@RunWith(MockitoJUnitRunner.class)
public class FeatureCollectorTaskTest {

	@Mock
	private FeatureCollectorRepository featureRepo;

	@Mock
	private FeatureSettings settings;

	@Mock
	private FeatureService featureService;

	@Mock
	private ListenableFuture<UpdateResult> future;

	@InjectMocks
	private FeatureCollectorTask featureCollectorTask;

	@Test
	public void shouldGetCollector() {
		FeatureCollector collector = featureCollectorTask.getCollector();
		assertNotNull(collector);
		assertTrue(FeatureCollector.class == collector.getClass());
	}

	@Test
	public void shouldGetCollectorRepo() {
		assertSame(featureRepo, featureCollectorTask.getCollectorRepository());
	}

	@Test
	public void shouldGetCron() {
		String cron = "cron";
		when(settings.getCron()).thenReturn(cron);
		assertSame(cron, featureCollectorTask.getCron());
	}

	@Test
	public void shouldCollect() throws InterruptedException, ExecutionException {
		ObjectId id = new ObjectId();
		long lastExecuted = 1;
		FeatureCollector collector = new FeatureCollector();
		collector.setId(id);
		collector.setLastExecuted(lastExecuted);
		Set<Project> projects = new HashSet<>();
		Project project = new Project("capitalone", "hygieia");
        projects.add(project);
		when(featureService.getProjectsToUpdate(id)).thenReturn(projects);
		when(featureService.updateIssuesForProject(eq(collector), isA(Project.class))).thenReturn(future);
		when(future.get()).thenReturn(new UpdateResult(1, 1));

		featureCollectorTask.collect(collector);

		verify(featureService).updateIssuesForProject(collector, project);
	}

	@Test
	public void shouldLogException() throws InterruptedException, ExecutionException {
		ObjectId id = new ObjectId();
		long lastExecuted = 1;
		FeatureCollector collector = new FeatureCollector();
		collector.setId(id);
		collector.setLastExecuted(lastExecuted);
        Set<Project> projects = new HashSet<>();
        Project project = new Project("capitalone", "hygieia");
        projects.add(project);
        when(featureService.getProjectsToUpdate(id)).thenReturn(projects);
        when(featureService.updateIssuesForProject(eq(collector), isA(Project.class))).thenReturn(future);
		when(future.get()).thenThrow(new InterruptedException());

		featureCollectorTask.collect(collector);

		verify(featureService).updateIssuesForProject(collector, project);
	}

}

redpajama_set_name: RedPajamaGithub


text:
Epidemiology: Long COVID in individuals with mild illness assessed
More than half of home-isolated young adults (aged 16–30 years) with mild COVID-19 experienced persistent breathing trouble, loss of taste and smell, fatigue or impaired concentration and memory 6 months after their initial infection in a study of 312 patients in Bergen, Norway, published in Nature Medicine.
Long-term complications following COVID-19 are common in hospitalised patients with severe symptoms, but the burden of so-called 'long COVID' in mild to moderately ill patients is not well understood.
To assess the long-term symptoms of individuals with mild COVID, Bjørn Blomberg and colleagues followed up with a group of 312 patients, who made up 82% of the total cases in Bergen during the first pandemic wave in Norway. This group comprised 247 home-isolated and 65 hospitalised individuals with a median age of 46 years, 51% of whom were women. Participants went to a clinic on a bimonthly basis to have their symptoms recorded by interview with a physician. At 6 months, 61% of all patients had persistent symptoms, which were independently associated with the severity of the initial illness. A total of 61 (52%) of home-isolated young adults continued to have symptoms at 6 months, including loss of taste and smell (28%), fatigue (21%), trouble breathing (13%) and impaired cognition (13%) and memory problems (11%).
The authors express their concern that some non-hospitalised young people suffer from potentially severe symptoms for as long as half a year after infection, and note that the high occurrence of persistent fatigue in COVID-19 patients is striking and appears to be higher than that observed after other common infections, such as influenza and Epstein–Barr virus mononucleosis. Considering the millions of young people infected during the ongoing pandemic, the authors argue for comprehensive infection control, population-wide mass vaccination and further investigation into the spectrum of symptoms in milder cases.


Think most people stick with what they have because it is too costly to chop and change. I gave up on Sony A77 and 70-400 combo did not cut it for bird photos (sharp enough for all other types of photography though) and their 500 f4 lens costing around 40% more than its worth. Then I switched to Nikon, bought the D7100 and 500 f4 lens (which is fabulous) but now getting held back by limitations of fps, ISO and buffer. Very frustrating.


text:
info@discoverthenature.com
ADVENTURE CIRCUIT
ESPELEOLOGY
ADVENTURE TRIPS
SURF EXPERIENCE
JEEP TOURS
The Professor Luiz Saldanha Natural Park created in 1998, constitutes an important rich and unique reserve at European level, housing more than 1400 species of marine animals and plants, which makes it the most biodiverse reserve in Europe.
The beaches along the coastline, the caves and the coves are of unique beauty, the clear waters invite you to take a dip.
In the Sado Estuary lies one of the rare sedentary populations of Roaz-Corvineiro in Europe and one of the most important in the world. With an estimated population of around 30 individuals, it is a privilege to see them evolve in the calm waters of the estuary, or to indulge in jumps and pirouettes that attract and sensitize us.
The observation of this small world where they play, hunt and spend most of their time, lasts approximately three hours, with the possibility of a short stop for a swim, and takes place in one of the most beautiful places in Portugal, the bay from Setúbal, also known as dolphin bay, which belongs to the restricted club of the "Most Beautiful Bays in the World".
Make sure you have a camera, and come and discover the secrets of our coastline!
SETÚBAL (3h)
DOLPHIN BOAT TOUR
SESIMBRA (3h)
SECRET BEACHES IN ARRÁBIDA - BOAT TOUR
ARRÁBIDA COVES - BOAT TOUR
Discover the natural wonders of the Arrábida Natural Park and the Sintra-Cascai Natural Park , get to know their natural values.
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