text:
Asia as a Region
CHIN-SAN-LONG, PIERRE VERGER, ARTHUR DE CARVALHO AND THERESE LE PRAT.
A Collection of 4 Chinese Photographic Reproductions of the 1930s
(c1930s). A collection of 4 striking black and white photographic reproductions from 1930s magazines with images on both sides. 34 x 26.2cm. Chin-San-Long was born in 1982 in the Huaiyin district of Jiangsu Province. Spanning the entire course of the development of photography in China, his photographic career began in..... More
EDITORIAL DEPARTMENT OF RODONG SHINMOON, ORGAN OF THE CENTRAL COMMITTEE OF THE KOREAN WORKERS' PARTY.
Self-Reliance and Independent National Economic Construction.
Peking. Foreign Language Press. 1963. 16pp, wrappers, evenly browned throughout, occasional browning covers, a closed tear upper cover repaired by archival tape, translated from Chinese into English. Original text was in Korean. 18.3 x 12.9cm. (When referring to this item please quote stockid 170559).	More
Price: $40.00 AU
HASLUCK, PAUL M.P. MINISTER FOR EXTERNAL AFFAIRS.
"The Place of Agriculture in Australian External and Planning".
16 typescript leaves, stapled in upper corner. The Agricultural Bureau Oration, in the Bonython Hall, Adelaide, Tuesday, 31st August 1965. Good copy. (When referring to this item please quote stockid 7393).	More
MEMBERS OF THE RED CROSS PYONGYANG ART TROUPE AND HOME VISITING GROUP BACK FROM SEOUL.
Notes on the Visit to Seoul.
Pyongyang. Foreign Languages Publishing House. 1985. Black and white photographic illustrations, 23pp, minor wears at extremities, good in wrappers. 20.5 x 11cm. "The Pyongyang Art Troupe and Home Visiting Group Back from Seoul, led by the chairman of the Central Committee of the Red Cross Society of the Democratic People's..... More
O'SHEA, HENRY. (EDITED BY).
Threatened Decline and Fall of Great Britain in China. A Review of the Present Political Situation in China.
Shanghai. China Gazette, 1903. First edition. New buff coloured wrappers with a portion of the original wrappers laid down on front and rear covers. 64pp, 23 x 14.2cm. A rare political pamphlet from The China Gazette outlining the British situation and offering possible solutions. There are notes on British trade..... More
SEOUL METROPOLITAN GOVERNMENT.
Games of The XXIVTH Olympiad Seoul 1988.
Seoul. Seoul Metropolitan Government. 1988. Folding 1988 Olympic Games brochure, 4 folds printed on both sides, colour illustrations, tables, minor wears on edges and corners, still good. 21.2 x 10.3cm when folded. Includes tourist information, schedule of the 24th Olympic Games, and information on tickets and accommodations. (When referring to..... More


text:
Poor human rights standards give US an edge
By Li Haidong Source: Global Times
Healthcare workers bring a patient into the emergency room at Maimonides Medical Center during the coronavirus pandemic in the Brooklyn borough in New York, the United States, April 8.File photo:Xinhua
Even though the US has launched its vaccine rollout, it is still a "bittersweet" movement for the country, said top US infectious disease expert Anthony Fauci on Tuesday, as the US has witnessed more than 300,000 coronavirus deaths. "Three hundred thousand is more than the number of Americans who died fighting in World War II," said The New York Times.
Over 3,500 coronavirus-related deaths were reported in the US on Wednesday, which is a new record. The figure is more than the death toll from the September 11 attacks, when 2,977 people lost their lives, and the attacks on Pearl Harbor during the World War II, when 2,403 died. As a matter of fact, daily deaths from the virus in the country have topped 3,000 for a while. It means the US is going through a September 11 or a Pearl Harbor attack almost every day lately. But US society is still functioning relatively stable despite this.
One of the reasons that explain the situation is that US political and public opinion elites are more enthusiastic about seeking enemies. When tragedies like September 11 or Pearl Harbor attacks occurred, they found definite enemies, so they could further hype up the disasters to cause an explosive sensation. But when it comes to the tragedy of the US epidemic response, it is exactly the political elites who should shoulder their responsibilities.
Because these people failed to handle the public health crisis well, they could be argued to be the enemy of people. At this point, they tend to protect themselves by creating new enemies, diverting Americans' discontent to the outside. This is a disgraceful move.
Apart from seeking a scapegoat, the US federal government also misled its people, such as calling the epidemic "a flu" which was "very much under control." In addition, despite the fact that US economy has been badly hit by COVID-19, its aggregate economic volume is still strong. Americans believe the country has enough resources to handle the ongoing crisis. So no major chaos has been triggered by the epidemic.
But the situation has totally turned peoples' view of the superpower upside down. A country that calls itself the beacon of human rights does no self-examination at all when facing so much loss of life. At this point, US politicians still believe human life is separate from human rights, and the epidemic is a public health issue, which has nothing to do with Americans' human rights. They have ignored the most essential meaning of human rights.
The US-style human rights can be thus argued as being quite low. Because of its staggering death toll, the country is actually facing a large-scale human rights crisis.
Social Darwinism, which focuses on natural selection and survival of the fittest in human society, has been dominating American elites' mentality since the founding of the country. It gives priority to freedom while neglecting equality. To cap it call, the "freedom" is only for stronger forces – the strong see their wealth and power increase while the weak see their wealth and power decrease until it is eliminated. This is what the notion of US-style human rights stands for when it comes to its own people.
Americans are surely dissatisfied with the status quo. The result of the presidential election is a sign they want to make a difference.
Will Joe Biden bring any major changes after assuming office? The answers could be quite uncertain. The political system of the US has so far proved that the federal government can only play a limited role in addressing the puzzle. This has led to the inaction of state governments. Moreover, political infighting is too fierce. Republican-led state governments may resist Biden's future requests in fighting the virus.
This may leave the American people further helpless. The gap between the US ultra-rich and the grassroots are simply too wide to bridge. This is a serious challenge confronting the country that does not have any easy course of action ahead.
The author is professor at the Institute of International Relations of the China Foreign Affairs University. [email protected]
Hariri Promises Macron to Seek French Initiative Success
Tariff war didn't work on China under Trump, won't work under Biden

redpajama_set_name: RedPajamaCommonCrawl


Voltage frequency transformation (V/F) is one of the widely used voltage controlled frequency conversion methods. There are two most commonly used modulation modes for V/F: the sinusoidal pulse width modulation (SPWM) and the space vector pulse width modulation (SVPWM). SPWM can basically meet the requirements in transmission, and it is also the most widely used method in frequency inverter, but when the motor runs at a low frequency, the maximum output torque decreases. The purpose of SVPWM is to generate motor circular magnetic field trajectory, which can improve the voltage utilization, but SVPWM can not adjust the torque conveniently.
Conventional voltage controlled frequency inverter has bad performance on dynamic response and steady state accuracy of the frequency converter output current. What's more, the waveform distortion of the output sinusoidal current is serious, which contains a lot of high-frequency harmonics, resulting in a decline of efficiency for the motor.
Vector control is a high-performance current controlled frequency conversion method. The vector control method uses Park transformation, Clarke transformation, inverse Park transformation and inverse Clarke transformation to decompose the stator current and get covariant with torque and magnetic field. However, this method depends a lot on the parameters of the motor, moreover, the rotor flux can not be measured accurately. For these reasons, the actual performance of the vector control based method is not good. As mentioned before, voltage controlled frequency inverters may not provide sufficient torque for the motor, the current controlled frequency inverter is studied in this paper. A current tracking based control method for frequency inverter is proposed. This method controls the output current of the frequency inverter directly, so the frequency inverter can control the motor output torque more easily, it can also be effective in preventing the occurrence of frequency inverter's overcurrent, and reducing the current fluctuations during the acceleration and deceleration process.
The basic idea of the frequency inverter current tracking method is to track the given sine wave signal based on the motor load, and then change the amplitude or frequency of the given sine wave. For implementation, a three-phase stator current is firstly gotten and compared with the given current signal. The bias current is then calculated, which is then put through a Proportion-Integration regulator. The PWM duty cycle of the inverter part is then regulated to make the three phase stator current approach the given current signal gradually. The current tracking control of the frequency inverter actually constitutes a current closed-loop control system.


Francisco Caputa, DDS, was ready for a life change in the summer of 1938.
He was sick of living in New Jersey, and had no roots to keep him there. His practice of five years was successful, but terribly boring.
That's why when his cousin Alesandro Carbone called and said he was retiring from his dentistry practice in Bisceglie, Italy, he asked if anyone else was taking his place?
When Alesandro said no one was, a crazy thought went through his head. Move to Italy? His ancestors were from Bisceglie. He only spoke broken Italian, but the allure of moving to an exotic location like Italy was strong.
A month later, after selling his practice in the small town of Millstone, Francisco moved to Bisceglie. At first, he stayed with his cousin while he searched for office space and an apartment.
Two weeks later he was ready to open. Alesandro helped him settle and vouched for him among the townsfolk. It wasn't long before he had a steady flow of customers. The people were friendly, especially when they found out his family once lived there three generations ago.
A month later, while drinking at a bar, a drunk Allesandro was talking about the special visitors who sometimes came to get dental work done…at night. "They pay well, just don't pester them with questions," his drunken cousin warned.
"That sounds strange to me," Francisco responded, slurring his words while trying to focus on what his cousin was telling him.
"I assure you it's an old practice, dating back hundreds of years, here in Bisceglie," Allesandro explained.
Two days later an elegant card was hand-delivered to him. The beautiful hand-written script was bordered with Black Roses. It said: "Appointment at 9 p.m. I look forward to meeting you." It was signed, Count Massimo Barzetti.
The hours slowly drug by. Francisco was torn between curiosity and dread as he puttered around his apartment. At ten to nine, he walked over to his office which was just a short way from the apartment.
Oddly, the streets were empty, unlike a few nights ago when he went on the drinking binge with Alesandro. He unlocked the door to his office and flipped on the light switch. No light. Frowning, he found his desk and lit the candle on it with his Zippo.
It was a small office with just two rooms. One with a dentistry chair and acudaments, and the other a bathroom. The waiting room consisted of his desk and three old wooden chairs by the window.
Promptly at 9 p.m., Count Massimo Barzetti, appeared outside the front door. He seemed to be waiting for something, so Francisco opened it for him. The tall thin man was dressed in a black casual suit and gold tie.
Once inside, he introduced himself and said it was time for his monthly cleaning and whitening. As surreal as it seemed, Francisco still managed to function and extended his arm towards the room with the dentistry chair.
"I'm going to need power," Francisco said in a daze.
The count waved his arm and the electricty was restored. He then calmly got into the chair and leaned his head back.
When the count opened his mouth, Francisco reeled back in fear and loathing. The sharp fangs were tainted by old blood!
"What contract?" Francisco managed to squeak in his suddenly high voice.
The room started to spin and Francisco felt faint with fear. He had to ask what happened if the "new" dentist decided to leave?
Francisco's choice suddenly became crystal clear.
"When was the last time you flossed?" he asked.
As It Stands, I admit to having an unnatural interest in vampires.


text:
Application and Challenges of Membrane in Surface Water Treatment
A.W. Zularisam, A.F. Ismail and M. Sakinah
Herein, we reviewed NOM and its components as the major membrane foulants during the separation and purification of water works. In addition, possible fouling mechanisms relating to NOM fouling, current techniques employed to characterize fouling mechanisms and methods to control fouling were briefly discussed. Conventional water treatment which involves a train of operating units such as coagulation, flocculation and sand filtration consumes substantial spaces and high Hydraulic Retention Time (HRT). Besides that it relies most on chemical consumption such as aluminium sulphate, ferric chloride and poly-aluminium chloride which end up as sludge waste contaminated with aluminium or ferric oxides. Furthermore, the chemical reaction between Natural Organic Matter (NOM) and disinfectant agent such as chlorine or chloramines has been extensively reported to form carcinogenic Disinfection By-Product (DBPs) which is potential in causing deleterious cancers diseases. Therefore, a more reliable and greener technology such as membrane technology has been employed as it possesses better capability in producing water of exceptional quality and practicality over the conventional treatment process. However, the widespread of this potential feature is significantly restricted by fouling issue which reduces its productivity, permeate quality and treatment performance.
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A.W. Zularisam, A.F. Ismail and M. Sakinah, 2010. Application and Challenges of Membrane in Surface Water Treatment. Journal of Applied Sciences, 10: 380-390.
DOI: 10.3923/jas.2010.380.390
URL: https://scialert.net/abstract/?doi=jas.2010.380.390
The need for water and wastewater treatments with regards to human consumption and industrial requirement are becoming more challenging as mankind continues to decline the finite water resources with more complex waste of pollutants contaminants. Looking at the most advanced water treatment process, it is apparent that the membrane technology is the today's state of the art. Small size in the plant, easier maintenance and superior water quality produce by membrane filtration has made this advanced technology possible to replace the conventional treatment processes (Clever et al., 2000). Though, membrane technology is fairly new to the water industry but yet its growth in treatment applications is tremendous (Table 1). This is due to a steadily decreasing manufacturing cost, a relatively lower chemical consumption and low maintenance compared to conventional treatment. Membranes remove contaminants ranging from suspended solids, colloidal, dissolved organic solutes by physical retention, chemical adsorption and back diffusion. Dissolved organic matter is ubiquitous in natural surface water and often reclaimed (Youravong et al., 2010; Mayani et al., 2010; Buetehorn et al., 2010; She et al., 2009; Berberidou et al., 2009) as important factor for both the reversible and irreversible fouling in water filtration.
Overview pore size operating, volume treated and application by membrane processes
Pressure driven membrane processes such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and Reverse Osmosis (RO) allows the production of high quality drinking waters. The MF unit is widely used for turbidity or fine particles removal and is an ideal pretreatment for processes using tighter membranes. The MF can be operated in dead-end or crossflow filtration mode with latter being advantage of having tangential flow to sweep foulants off. But this high flow rate requires more energy and usually reserve for high solids water content. Apart of that, the UF only became popular in water treatment only recently, primarily due to its ability to remove bacteria or other microorganisms but it could only be effective either with a PAC or coagulant pretreatment which makes the operation more complex and generate a waste stream. Earlier studies using integrated conventional coagulation followed by direct membrane filtration or an inline coagulation combined with direct membrane filtration (Neubrand et al., 2010; Beyer et al., 2010; Mariam and Nghiem, 2010) have demonstrated effective control of fouling, improved membrane permeability and superior permeate quality despite having applied on low quality water sources. The NF is often more appropriate in water treatment as the product is not fully demineralized. The membranes used exhibited high organic removal but moderate calcium and alkalinity permeability made the process more economic compared to RO. However, the disadvantage of NF and RO are high energy cost, proper pretreatment and generation of waste streams that need further treatment prior to disposal. In spite of providing many advantages over the conventional treatment, fouling issue is the main challenge in membrane filtration efficiency as it causes reduction in permeates quality and filtration productivity. Productivity decline can be defined as a decrement in flux with time of operation due to the increment of hydraulic resistance. Productivity decline may also be interpreted as a need for additional energy supply to the filtration system so as to keep the system performance constant. Whereas fouling phenomenon is caused by particles smaller than membrane pores being adsorbed into the membrane pores then followed by particles of similar size to pore diameter before cake formation by deposited particles (Neubrand et al., 2010; Ladner et al., 2010). Therefore, a fundamental knowledge on the possible foulants and how they cause fouling are essential before any remediation works is carried out.
Microfiltration (MF): Microfiltration is used in a wide variety of industrial applications where particles of a size greater than 0.1 μm, have to be retained from a liquid. Applications include the sterilization and clarification of all kinds of beverages and pharmaceuticals and in particular pre-treatment for subsequent finer membrane filtrations, especially in water and wastewater treatment. Physical sieving is the major rejection mechanism for MF with water convecting through the membrane due to an applied TMP. The deposit or cake on the membrane can act as a rejecting layer and retain even smaller solutes than would be expected to be retained. Thus, a fouled MF membrane may have UF rejection characteristics and flux may decline significantly due to build up of this deposit. Electrostatic interactions, dispersion forces and hydrophobic bonding may play some role in rejection.
Ultrafiltration (UF): Ultrafiltration and nanofiltration, in particular, are important processes for the removal of solutes, macromolecules (such as natural organic matter) pathogenic viruses and small colloidal materials in water and wastewater treatment. The production of potable water from seawater or brackish water by reverse osmosis has become increasingly important, especially in remote areas such as island, sea and inaccessible locations. The UF can as well be used for NF and RO pretreatment, which may lengthen the filtration cycle of these processes compared to a MF pretreatment. As MF, physical sieving is an important rejection mechanism in UF and convection dictates solvent passage. The deposit can also act as a self rejecting layer and charge interaction as well as adsorption may also play an important role. Rejection is usually evaluated with macromolecules of different MW such as dextran or proteins, which leads to the determination of MWCO.
Nanofiltration (NF): The NF is a process located between UF and RO. Some researchers refer NF as charged UF, softening membrane and low pressure RO. The NF is generally expected to remove 60 to 80% of hardness, 90% of color and all turbidity. The process has the advantage of low operating pressures compared to a significant to RO and high rejection of organics compared to UF or MF. However, the monovalent salt is not well retained to a significant extent as his is not normally required in water treatment of surface water. Rejection of membranes is usually evaluated by manufacturer with NaCl or MgSO4 solution as opposed to MWCO speciation in the UF. Rejection mechanisms based on charge and size are important in NF. At neutral pH most NF membrane are negatively charges while at low pH they are mostly positive in charge. Physical sieving is the dominant rejection in NF for colloids and large molecules whereas the chemistries of solute and membrane become increasingly important for ions and lower molecular weight organics.
Reverse osmosis (RO): In RO the osmotic pressure of a solution has to be overcome by an applied transmembrane pressure (TMP) to achieve solvent flux and separation. Recovery (ratio of product per feed) has a high impact on flux and rejection and both decrease with increasing recovery. Physical sieving applies to colloids and large molecules. Besides that, RO rejection is mostly a function of the relative chemical affinity of the solute to the membrane material. Ion rejection follows the lyotropic series which means that rejection is increased with increased hydrated radius of ion. The order of the ions however, may change due to ion pairing, complexation or other solute-solute interactions, thus difficult to predict rejection of ion mixtures. The rejection behavior in the presence of organic is still poorly understood and only trends can be noted. In general RO rejection is usually evaluated with NaCl or MgSO4 solutions permeation.
Challenges: Membrane filtration processes involving microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and Reverse Osmosis (RO) have steadily gained importance in the environmental engineering separations over the past decade. Numerous improvements in the technology have caused widespread applications of this process in environmental, chemical, pharmaceutical and biomedical fields. However, several aspects of this evolving membrane technology has not yet been addressed conclusively and thus, potentially posing obstacles toward its wide adoption such as inevitable fouling problems, costs factor, know-how technology and unsuitable imported technology.
Know how technology: It is vital to identify membrane foulant and fouling mechanisms before membrane fouling can be alleviated or control. Clear fundamental knowledge on understanding and minimization of membrane fouling are important and can be realized though accurate process design and optimal operating conditions. Maintaining proper operating conditions, accurate pretreatment process, suitable cleaning solution or techniques and proper membrane selection for specific membrane application is the key preventative step to minimize membrane fouling and maintaining high membrane productivity. Apparently membrane efficiency in filtration operation depends greatly on tedious management of fouling. Membrane fouling is the prime bottleneck that retards the membrane effectiveness and wide application. The usage of suitable membrane design, construction, configuration and fouling control techniques will result in longer membrane life, lower operational and design costs. Membrane operating management comprises physical and chemical procedures. Physical methods such as intermittent backwashing, application of critical flux, critical TMP, intermittent suction operation, low TMP, high Cross Flow Velocity (CFV) and hydrodynamic shear stress scouring effect produce only temporary recovery of membrane flux and require high energy consumption. On the other hand, the application of effective chemical cleaning agents such as NaOCl, NaOH, HCl and HNO3 has been proven to completely recover the initial membrane permeability. However, these procedures are expensive, can cause severe membrane damage, chemical contamination and may produce toxic by-product wastes. Backwash technique is dependent on the nature of fouling mechanism and only suitable in back flushing weak adhered cake layer. In the case of pore plugging and pore adsorption (irreversible fouling), the consumption of chemical agent is more favourable. Surface water pretreatment prior to membrane filtration can be done either by adjusting the solubility of NOM or reducing the NOM concentration using precoagulation. Aluminium-based or iron-based coagulants had long been used to remove NOM in the conventional method. Subsequently pretreatment of coagulation prior to membrane filtration has also been employed to enhance the permeate quality as MF and UF alone are inadequate. Since, MF/UF has their own limitations due to their larger molecular weight cut off (MWCO) to the relative molecular mass of NOM, pretreatment processes such as coagulation and PAC would definitely help to improve these weaknesses and are capable to meet water quality requirements for NOM removal.
Fouling problems: Fouling is still the single most important problem that retards the widespread use of membrane separation processes as it could cause high operational and maintenance costs, lower productivity and permeate quality and high frequency of membrane regeneration. Membrane fouling can be defined as the decline in permeate flux or an increase in TMP. The flux decline results from a number of complex kinetic processes that lead to gradual deposition of solids on membrane surface or gradual blockage of the membrane pores. Four types of foulants may be distinguished: chemical foulants, which cause scaling, physical foulants, which are related to deposition of particles, biological foulants, which can form bio fouling and organic foulants, which can interact with the membrane. In general membrane with larger pores exhibit a greater flux decline compared to smaller one. This could be reason due to significantly higher intrinsic fluxes and the increased possibility of internal fouling. One important issue in membrane fouling is due to concentration polarization and cake formation of particulate materials. Concentration polarization is a phenomenon wherein there is a concentration of particles in a thin layer adjacent to the membrane which has the effect of reducing flow through the membrane. Cake formation is the accumulation of particulate matter on the membrane surface. Whereas pore blockage is due to deposition of foulant in the membrane pores.
Cost and recovery of several membrane and hybrid filtration system
Cost factor: Membrane process and membrane technology have changed significantly in recent years. The required membranes characteristics depend greatly on the application and the desired permeate quality. As emerging technologies, there are many unknowns regarding the cost-effectiveness of membrane processes such as ultrafiltration (UF) and nanofiltration (NF) and RO for the potable water treatment. Uncertainty is related to the process performance and lack of design history. For example, the permeation rate that reasonably can be anticipated when treating raw water using a given membrane has great impact on the capital and operating costs that are estimated for a membrane installation. The RO membrane process produces water of exceptional quality but is found to be less cost effective compared to other membranes.
On the other hand, NF represents an interesting trade-off between the high energy requirement RO and the low rejection UF membrane. If water is turbid but not colored or polluted, MF is an attractive alternative due to its low cost operation. The RO process cost reduced by 30 to 40% after the development of MF pretreatment whereas it concluded their cost modeling with comments that cost is largely a function of flux as the flux determines the membrane area to be installed. At small design capacities (<20, 000 m3), MF and UF costs were competitive with conventional treatment. The UF was less costly than MF for larger facilities (>20,000 m3). The importance of particle size in cost evaluation was also pointed out where cost has been found to increase with particle concentration as well. The UF membrane was cost competitive with conventional treatment for low particle (up to 20 mg L-1) if particles are 0.1 μm on average. The total treatment cost describing the capital and operating costs are shown in Table 2.
Efficacy of imported technology: Membrane technology for surface water treatment is considered to be the most promising development in water treatment as it could provide permeate quality far beyond the current regulatory requirement for potable water consumptions. However, lack of field experience, surface water database and knowledge on specific geographical surroundings, the efficacy of imported membrane is therefore, questionable and may not be optimal to be directly applied in our tropical area. Although, this technology is even becoming more attractive with a package of a compact technology (small footprint) and superior permeate quality, problems related to low membrane life, expensive membranes that are prone to fouling and questionable permeate quality are still a major issues in membrane treatment process especially in our country. In particulars there are still many technical challenges which need further optimization so as to ensure membrane technology remain competitive in the market especially for large scale industry. There is a need for further research of advanced membrane materials that are resistant to both chemical and mechanical attacks during surface water treatment (such as Sg Bekok and Yong Peng water intake) as this would help in prolonging the membrane lifespan and induce long term performance. The identification of the best practices in terms of design, treatment configuration and operating parameter that suit to this tropical climate would help to project minimal capital for design, construction and operational costs. The development of clear fundamental knowledge on understanding and minimization of membrane fouling (due to NOM and particulates in surface water) are also vital and can be realized through employing accurate process design and operating conditions. Furthermore, proper selection of pretreatments, improvement of cleaning strategies and membrane system with low energy requirement may help to position this technology to reach market confidence.
SURFACE WATER FOULANTS
Foulant and its fouling mechanisms are extremely vital to be identified before one can alleviate the membrane fouling. Membrane fouling refers to both reversible and irreversible alteration in membrane properties. Reversible fouling means deposition of retained solutes on the membrane surface that generally exists as a gel cake layer. Irreversible fouling refers to adsorption or pore plugging of solutes in and within the membrane pore matrix. Concentration polarizations are the accumulation of retained materials in the boundary layer above the membrane due to osmotic pressure and hydraulic resistance effect. Increment and variation of hydraulic resistances may come from variety of organic substances, inorganic particles, colloids and microorganisms with different fouling behaviors. The fouling behavior is significantly found to be influenced by various chemical and physical factors of the foulants. The foulant can be characterized according to their molecular structure, surface charge, molecular size and functional groups. One of the most important identified foulant found in surface water filtration is Natural Organic Matter (NOM). The NOM waters are a complex mix of particulate and soluble components of both inorganic and organic origin that vary from one source to others (Howe et al., 2002). The NOM is a heterogeneous mixture with wide ranges in Molecular Weight (MW) and functional groups (phenolic, hydroxyl, carbonyl groups and carboxylic acid) and is formed by allochthonous input such as terrestrial, vegetative debris and autochthonous such as algae. Natural organic matters that occur in natural brown water are polyphenolic molecules with MW ranging from 5000 to 50000 Dalton (Maartens et al., 1999). In particular, NOM can be fractionated into three segments; the hydrophobic fraction (humic substances), hydrophilic and transphilic. The hydrophobic fraction represented almost 50% of dissolved organic carbon (Fig. 1) with larger MW. The hydrophilic fraction composed 25-40% of Dissolved Organic Carbon (DOC) with lower MW (polysaccharides, amino acids, protein and etc.) and operationally defined as non-humic fraction. The transphilic fraction comprised approximately 25% of DOC in natural water but with MW in between hydrophobic and hydrophilic fractions. A major fraction of the NOM arises from humic substances and is reported to represent up to 60 to 70% of TOC in soils and 60 to 90% of DOC in most natural water. Fan et al. (2001) reported the major fraction (over 50% of DOC) of NOM is composed of humic substances and are responsible for the natural water's color. A humic substance is the predominant fraction of NOM and generally is divided into three categories, which are Humic Acid (HA), Fulvic Acids (FA) and humin. The HA and FA are anionic polyelectrolyte with negatively charged of carboxylic acid (COOH¯), methoxyl carbonyls (C=O) and phenolic (OH¯) functional groups. Figure 2 and 3 show both models of humic acid and fulvic acids structures. Humic acid is soluble at higher pH normally 10 while fulvic acid is soluble in water under all pH. Humin is naturally exists in black color and does not soluble in water at any pH (Fig. 4). Humic fraction has been identified as the major foulant in membrane water filtration, which controls the rate and extent of fouling (Combe et al., 1999). It causes more fouling than any other NOM components due to its adsorptive capacity on the membrane surface (Wiesner and Aptel, 1996). Study done by Mallevialle et al. (1989) showed organic matrix formed a structure of fouling layer that served as a glue for inorganic constituents. Similar results were reported by Kaiya et al. (1996) in analyzing deposited layer formed on a MF hollow fiber during filtration of Lake Kasumigaura water. The NOM deposition has been found as the dominant factor causing flux decline along with manganese constituent. Study by Mo and Huang (2003) on purification of micro-polluted raw water revealed that fouling on the exterior surface was a combined effect of microorganisms and inorganic matter while on the inner surface was mainly due to the biofouling.
Fig. 1:
Fraction of NOM in surface water based on DOC (Thurman, 1985)
Schematic of humic acid model structure
Schematic of fulvic acid model structure
Physical and chemical characteristics of humic substances (Stevenson, 1982)
They found the organic foulants were of low molecular weight and the inorganic was primarily represented by Ca2+ element. Their investigation on membrane permeability recovery showed that alkaline cleaning was effective in removing organic foulants while acidic cleaning was more effective on inorganic scales. It has also been shown that hydrophobic fraction of NOM causes much more fouling than hydrophilic fraction (Nilson and di Giano, 1996).
They performed NF of a hydrophilic membrane with aquatic NOM using DAX-8 to fractionate the NOM components. Hydrophobic fraction (absorbable to DAX-8) was mainly responsible for the permeate flux decline. On the other hand, the hydrophilic component which passed through DAX-8 showed less fouling effect. Humic macromolecules with higher hydrophobicity are found to favourably adsorb onto hydrophobic membrane than hydrophilic fraction (Jones and O'Melia, 2000). Earlier studies done by many researchers showed that humic substances caused irreversible fouling of membranes. Yuan and Zydney (1999) studied humic acid fouling on a 0.16 μm hydrophilic MF and found that aggregate humic acid was responsible for the initial stage of fouling. Furthermore, fouling mechanism was substantially due to convective deposition with little internal pore adsorption. This finding is well supported by Schafer et al. (2001), who observed humic acid to cause 78% decline in flux compared to fulvic acid (15%). Humic acid was observed to give greater impact on membrane performance (irreversible fouling) than FA and hydrophilic fraction (reversible fouling). This scenario might be due to its high aromaticity properties, adsorptive behavior, hydrophobic and bigger molecular weight that lead to tendency of fouling. Similar result was also reported by Turcaud et al. (1990) during ultrafiltration observations with several organic and inorganic of Seine River. The flux decline observed was primarily due to humic acid deposition on the membrane surface. The cellulose acetate membrane (hydrophilic) flux was twice times greater than hydrophobic polyethersulfone (PES) during UF of river water. The hydrophilic components were thought to impact water quality less than the humic fraction, however recent studies done by Lin et al. (1999) and Carroll et al. (1999) have claimed that the non-humic fraction of NOM (hydrophilic and neutrals) materials were responsible in determining the rate and extent of flux decline. Carroll et al. (1999) performed MF of hydrophobic hollow fibre membrane with a single water source and concluded that the major cause of fouling was due to the hydrophilic neutral and not the humic substances. Fan et al. (2001) reported the order of fouling potential of NOM fraction as hydrophilic neutral >hydrophobic acids >transphilic acids >hydrophilic charged. They found that hydrophobic membrane had the most fouling effect than hydrophilic membrane of similar size suggesting that the fouling mechanism was governed by adsorption. In addition high molecules weight components had been identified as having the largest impact on membrane fouling compared to smaller DOM. This finding was well supported by study carried out by Lee et al. (2002). They found that polysaccharides and protein that have larger size of MW and lower UV to HPSEC-DOC/UV response, to significantly fouled their low pressure (MF/UF) membrane. Polysaccharides are aldehydes derivatives of high polyhydric alcohols, which have neutral characters that can cause adsorption on a charged hydrophobic UF membrane (Aiken et al., 1992). They suggested that the neutral NOM fractions with larged sized were the prime foulants rather than humic substances. Speth et al. (2000) in their study also found hydrophilic neutrals fouled more than hydrophobic acids. It can be reasoned that since, polysaccharides (hydrophilic neutral) has a bulky macromolecular shape and with no electrostatic effect would definitely be prone to foul and adsorb on membrane surface. Lin et al. (1999) performed a study on the effect of fractionated NOM onto a negatively charge UF membrane and observed that both larged-sized molecules of hydrophobic and hydrophilic of NOM components caused worsen flux decline. However, the hydrophilic fraction was found to induce the worst fouling. Jarusutthirak et al. (2002) in their study on the effect of effluent organic matter for UF membrane also found that the high molecular weight of hydrophilic component was responsible as the prime contributor of NOM fouling. It can be claimed NOM fouling was a result of low UV absorbing compounds and high molecular weight hydrophilic components that occurred through adsorption mechanisms. Inorganic particles can also affect the fouling behaviors of the organic substances. Presence of inorganic particles such as clay minerals in the surface water incurred a significant influence of competition between NOM and inorganic particles to adsorb onto the membrane surface or in the pores. High surface areas of inorganic particle enhance adsorption of organic substances on clays minerals and affect the fouling characteristic. This results in either enhancing particle deposition on the membrane or would decrease sorption of NOM onto the membrane and hence, increase the membrane permeability. But opposite finding was experienced by Hong and Elimelech (1997) when studied the effect silica (inorganic particle) on fouling of zirconia tubular membrane.
FOULANTS IDENTIFICATION IN SURFACE WATER TREATMENT
A number of techniques including inline Attenuated Total Reflection (ATR) Fourier transform infrared (FTIR) spectrometry, UV254, SEC-DOC, DOC fractionation, pyrolysis-GC/MS, UF fractionation, SEM, SEM with Dispersive Spectrometer (EDS) and AFM to analyze and characterize membrane foulant. The ATR-FTIR spectrometry can provide insight of foulant nature in the membrane texture that appears to be a valuable tool for foulants autopsy (Her et al., 2000). The FTIR can also be used to determine the functional groups of certain unknown foulants which corresponding to their vibrational energy of atomic bonds. Different functional group would absorb energy at different specific wavelength that latter can be translated in intensity response. Frequent absorption bands seen are shown in Table 3. But this method may also be insignificant in identifying of certain functional groups when the absorption reading gives broad overlapping bands. This phenomenon occurred due to heterogeneity of natural waters. Researchers (Aiken et al., 1992; Kol and Konieczny, 2003) used UV254 absorbance at 254 nm to measure the permeate and retentate of rejected compounds specifically for humic substances.
Common IR spectra for humic substances, polysaccharides and proteins
The presence of unsaturated compounds would generally produce a distinct color and can therefore, be detected by UV-Vis (Bruchet et al., 1990). The UV254 absorbance is sensitive to aromatic components and is an indicator for both humic acid and fulvic acid presence. Sample will first be filtered through 0.2 μm to remove particulate matter and DI is used as a blank. Difference in reading of UV254 absorbance between feed and permeate indicates the quantity of rejected humic substance by the membrane. The SUVA or specific ultraviolet absorbance is a ratio of UV at the wavelength of 254 nm and DOC. High SUVA means high aromaticity or hydrophobicity of sample in that limited DOC. Permeate from membrane filtration process which is found with high SUVA value is conforming that most of the rejected compounds are non-humic and that resulted in high value of UV254 in the permeate. Earlier studies reported that SUVA of NOM from natural waters or ground waters was in the range of 2.4-4.3 to 4.4-5.7 L mg-1 m, respectively (Krasner et al., 1996; Gray et al., 2004). The molecular weight distribution of NOM was normally determined using high performance liquid chromatography (HPSEC) with online UV and DOC detection (Schafer et al., 2000). The HPSEC contains a porous gel that allows separation of molecules based on their mass and MW. Smaller molecules will access most of the pore volume while larger molecules that cannot pass the pores will be eluted first. Subsequently non-humic compound with large molecular weight such as carboxylic protein and polysaccharides will exhibit significant DOC peaks but with low area of UV254 peak. On the other hand, humic fraction such as humic acid and fulvic acid will exhibit high peaks with molecular mass between 500 daltons to 2000 daltons with high UV response.
Schematic diagram of HPO, TPI and HPI fractionation
The most common technique for isolation of NOM fractions are gel filtration, ultrafiltration and adsorption using non-ionic macro-porous ion exchange resins DAX-8 and XAD-4 (Bowen et al., 1995). The surface water is fractionated into hydrophobic (HPO) which is DAX-8 adsorbable, transphilic (TPI) fraction which is XAD-4 adsorbable and hydrophilic (HPI) components which pass through the DAX-8 and XAD-4 resin without any adsorption Fig. 5. Application of pyrolysis and GC/MS tool as an analytical method to characterized complex organic matter had been successfully employed by Speth et al. (2000) and Jarusutthirak et al. (2002). A recent study done by Speth et al. (2000) using pyrolysis with GC/MS showed that hydrophilic fraction of NOM were the major foulants for a river water filtration. Pyrolysis-GC/MS method was developed by Bruchet et al. (1990). This tool is useful for characterizing NOM in terms of biopolymers such as polysaccharides, polyhydroxyaromatics, amino sugar and protein. Pyrolysing process would casue refractory compounds to release volatile fragments, which are separated and analyzed by GC/MS. Those fragments are then characterized by relative percentages according to their biopolymer. However, pyrolysis -GC/MS technique is considered as a semi quantitative technique due to variation of fragments characteristics with their biopolymer structures. Beside that almost 50% of the total peaks would be classified as miscellaneous and the standards used also may not be effectively representing the classes of required compounds. The ATR-FTIR and DOC fractionation methods using non-ionic macro-porous ion exchange resins such as DAX-8 and XAD-4 have been the most popular techniques used by many researches to characterize the NOM. But the ATR-FTIR may generate unreliable IR spectra readings due to overlapping bands. In addition, the DOC fractionation through ion exchange resins (DAX-8 and XAD-4) would exhibit total DOC recovery of less than 100%. This result can be reasoned due to improper elution procedure of DOC from the resins or the employed commercial NOM does not represent actual NOM in natural environment as it would vary with season and origin.
FOULING MECHANISMS IN SURFACE WATER TREATMENT
The extent of rejection of solutes by membrane is the most critical parameter in membrane filtration. For a clean membrane the extent of rejection is largely influenced by pore size whereas for a fouled membrane it is determined by the electrostatic interactions between the solute and membrane. Fouling of membrane is likely to happen in many instances due to a number of mechanisms such as pore blocking of solutes, cake deposition and precipitation of inorganic and organic particles at the membrane surface. Bowen et al. (1995) elucidated the consecutive steps of membrane blocking in flux decline during MF as follows: (1) the smallest pores are blocked by all particles arriving to the membrane, (2) the inner surfaces of bigger pores are covered, (3) some particles arriving to the membrane cover other already arrived particles while others directly block some of the pores and (4) a cake starts to be built. The NOM fouling mechanisms on membrane processes are different and are dependent upon membrane types. For MF, pore plugging, pore blockage and cake formation were found responsible for fouling that reduces pore size and increases rejection. In case of UF, internal pore adsorption reduces the internal pore diameter and enhances rejection while in NF the fouling mechanism is mostly governed by cake deposition and concentration polarization. Many researchers suggest humic substances play a vital role in irreversible fouling of membranes. Maartens et al. (1998) claimed UF membranes can remove NOM from natural brown water up to 98% but this progress impacted in flux decline in permeate volume that was due to irreversible fouling mechanism. Hydrophobic interaction between the hydrophobic NOM fraction and a hydrophobic membrane may cause more flux decline than that of hydrophilic membrane. The NOM with variety of organic fractions of different hydrophobicity, hydrophilicity, molecular weight, sizes and charge densities would give different interactions in membrane filtration. Yuan and Zydney (1999) have found that NOM adsorbed both inside the pores and on the membrane surface to form a cake layer. A cake layer formation is generally known to occur during surface water filtration using tight UF, NF and RO while pore blockage or direct adsorption is usually happened when using the MF. A cake layer formation is caused by electrochemical interaction and the degree of accumulation is depending on a balance between convective transport of solutes towards the membrane and back diffusion transport. Transport of large particle by drag force (convective force) is governed by an orthokinetic mechanism (inertial lift and shear induced diffusion). Inertial lift induced by wall effect tends to reduce larger particle to the membrane especially at high CFV. Furthermore, the shear-induced diffusion is found to increase back transport of particles. Both of inertial lift and shear-induced diffusion involving backtransport are functions of particle size. The larger the particle the higher possibility it will be back transported (Chellam and Weisner, 1997). On the other hand, back transport of small particle is controlled by Brownian diffusion, which has less effect compared to inertial lift and shear induced diffusion. Subsequently large particle in cake tend to produce less resistance for the same mass of deposited. Turcaud et al. (1990) described that NOM fouling was primarily governed by pore adsorption and gel formation. In their study, they experienced 25% flux reduction for the first 5 min of 1 nm UF hollow fibre of 10 mg L-1 humic acid filtration and a further declination of flux (55%) after 300 min. They concluded the first 5 min rapid declination was due to irreversible adsorption of humic acid foulant. The continued flux decline was claimed to cause by humic acid gel deposition (reversible fouling) by convective transport.
MEMBRANE FOULING CONTROL
Membrane fouling is the prime bottleneck that retards the membrane effectiveness and wide application. Usage of suitable fouling control techniques will result in longer membrane life and low operation cost. Fouling control comprises physical and chemical procedures. Physical methods such as intermittent backwashing, application of critical flux, critical TMP, intermittent suction operation, low TMP, high Cross Flow Velocity (CFV) and hydrodynamic shear stress scouring effect produce only temporary recovery of membrane flux and require high energy consumption. On the other hand, application of effective chemical cleaning agents such as NaOCl, NaOH, HCl and HNO3 have been proven to completely recover the initial membrane permeability. However, these procedures are expensive, can cause severe membrane damage, chemical contamination and may produce toxic by-product wastes. In practical engineering chemical cleaning is very effective in removing the deposited foulant and can be adopted as a long term solution for inevitable fouling but this procedure is out of focus of this study. Backwash technique is dependent on the nature of fouling mechanism and only suitable in back flushing weak adhered cake layer. In the case of pore plugging and pore adsorption (irreversible fouling), consumption of chemical agent is more favourable. Surface water pretreatment prior to membrane filtration can be done either by adjusting the solubility of NOM or reducing the NOM concentration using precoagulation. Aluminium-based or iron-based coagulants had long been used to remove NOM in the conventional method. Subsequently pretreatment of coagulation prior to membrane filtration had also been employed to enhance the permeate quality as MF and UF alone are inadequate. Since, MF/UF has their own limitations due to their larger Molecular Weight Cut off (MWCO) to the relative molecular mass of NOM, pretreatment processes such as coagulation and PAC would definitely help to improve these weaknesses and capable to meet water quality requirements for NOM removal. However, Turcaud et al. (1990) stated coagulation pretreatment could only reduce the rate of reversible fouling but not the irreversible fouling of low molecular weight polysaccharide compounds. Carroll et al. (1999) found that coagulation can be used as an efficient pretreatment to improve NOM removal and minimize fouling in MF of surface water. Coagulation of colloidal material and NOM are found to reduce the rate of fouling by aggregating fine particles that result in improving cake permeability, less dense, highly porous flocs and precipitation or adsorption of dissolved material into flocs. Increased in particle size by coagulation help to reduce foulant penetration into pores and forming a higher permeability cake on the membrane surface. Besides that coagulation can also be used to assemble microorganisms with coagulated matters though it is not as effective as other disinfectant agent. Maartens et al. (1998) suggested alteration of pH and application of metal-ions as pretreatments techniques of feed water as to reduce fouling of polysulfone UF membrane that was caused by Natural Brown Water (NBW). The NBW with pH 7 managed to sustain at 69% of its original flux after 300 min filtration whereas NBW with pH 2 was only 33%. In their experiment of using coagulants as pretreatment agents, they hypothesized that presence of Al3+ and Ca2+ in the NBW would help to block the functional groups of NOM by forming large precipitated organic material of metal-ions and hence, influence the potential of adsorptive behavior of NOM membrane-binding activities. However, results of their study indicated precoagulation with metal-ions could not prevent membrane fouling but as a matter of fact resulted in an increased of NOM adsorption and a much worse irreversible fouling mechanism. They explained the increased fouling to the greater adsorption of NOM to the PSF membrane (40 kDa) caused by metal-ions complexes.
Fouling of NOM happens by many factors and mechanisms. Factor affecting NOM and membrane interactions include NOM characteristics, operating conditions, membrane characteristics and solution chemistry. The NOM fouling occurs when dissolved organic or inorganic solute adsorbs or deposits on the membrane. Adsorption mechanism happens more instantaneous and rapid compared to cake formation but depending on the membrane properties, ionic strength, pH and presence of divalent cation. Solute deposition or gel formation occurs parallel with the magnitude of a convective flux and the extent of concentration polarization. Hydrophobicity and electrostatic interactions between solute and membrane are also reported to be the dominant factors that affect the extent of NOM fouling. Presence of electrolyte composition, low pH and high ionic strength had been found to strongly enhance the degree and rate of fouling. The MF and UF are drinking water treatment processes, which are particularly suitable for the removal of suspended solids and colloidal materials such as bacteria, algae, protozoa and inorganic particulates. However, this type of filtration mode is less successful for the removal of dissolved contaminants especially NOM in the surface water. Coagulation had been introduced to address this weakness as it is proven effective for decreasing hydraulic resistance, increasing critical flux and improving NOM removal. There is still controversy over on how the NOM affects the membrane fouling mechanisms. Some studies suggested that charge interaction and adsorptive behavior are the responsible factors that control the NOM fouling whereas others claimed convective and diffusive particle transport that mainly dominate fouling in NOM filtration. As a matter of fact many earlier studies were done using various types of membranes and were operated at high fluxes in their experiment with regards to NOM fouling. These conditions would contribute to physical accumulation due to convection, diffusion and adsorptive fouling. As a result it as difficult to distinguish the dominant factor that responsible to the fouling. Hence, further study needs to be carried out in order to clarify this ambiguity and help in proper selection of membrane property, membrane configuration, pretreatment and operating conditions.
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Relaxation is essential, which is why Mesquite is the perfect place for your next 18-holes.
CasaBlanca Golf Club features an 18-hole, 7,011-yard championship course designed by Cal Olson. The 18 holes wind through the region's natural desert wetlands offering wonderful views of the surrounding Virgin River Mountains.
You'll love the front nine at the Palms Golf Club, offering extended fairways, perfect for the long drivers. The back nine provides a mountainous style of golf where shot placement is key.
Played during November just after over-seeding. They had to best greens, then Palms, then Canyons, then Palmer. The clubhouse folks are very nice. Course demands they you stay in the fairway. One fairway had some flooding but is rebounding.


text:
[rev_slider ArneSvenson]
Arne Svenson
by Aaron Leaf
"I am much more interested in the way light illuminates the turn of an arm or the back of a head, conveying an infinity of possible situations and emotions, than I am of capturing a face which, in all probability, when confronted with a camera will be shrouded in well-practiced, derivative expressions."
Despite the public fervor whipped up over Arne Svenson's telescopic intrusions in his watershed series The Neighbors, the photographer is certain that his images were never intended to be about surveillance—and the courts of New York agreed, exonerating him twice from claims of privacy invasion. Svenson argues that his act of non-consensually photographing his neighbors from windows was instead intended to capture the nuances of motion.
The right to photograph people in public has long been established legally. It's the cornerstone for a surveillance regime that blankets practically every corner of our cities and leads to the adoption of new technologies like police drone surveillance. Many artists, Trevor Paglen for example, are trying to engage directly with the surveillance state and questioning its power and challenging its basis. But how does Svenson see his place among these artists? We reached out to Svenson in New York to try and explain this disconnect between how he sees his art and how the greater public might see it.
RUINS: We've seen your work labeled as "surveillance art," a medium that Andy Warhol helped to popularize and which has historically been interested in the idea of privacy, national security issues, and the act of secretly documenting something. Your work, despite the mechanical similarities, seems to focus far more on gestures and moments rather than the political underpinnings around the work's production. What do you think of this label and how it applies to you?
SVENSON: Given the nature of the work, I think it inappropriate: surveillance, and the topical issues surrounding it, was the furthest thing from my mind when I began shooting for The Neighbors project. My intent was to record the nuances of motion, or lack thereof, which reveal who we are, the tiny scenarios and gestures that define our humanness. Vignettes of quietude were what I was really searching for—those times when we are drained of action and contemplation becomes a visible, recordable event. I felt that the only way to capture these small ripples of emotion were if the subject was unaware of being photographed, hence my turning the camera to the building across from my studio.
Also, regarding the surveillance label: Throughout the series I was stringent in not revealing the identities of the subjects because to do so would have severely restricted the narrative possibilities inherent in the photographs. I am much more interested in the way light illuminates the turn of an arm or the back of a head, conveying an infinity of possible situations and emotions, than I am of capturing a face which, in all probability, when confronted with a camera will be shrouded in well-practiced, derivative expressions.
Shooting through windows gives the images a "painterly presence" that you seem to have pushed even farther with Workers. What do these overt connections between your images and academic painting mean to you?
I've long been interested in melding thematic, stylistic and illusionary aspects of painting and photography, but when I started shooting The Neighbors I had no idea that any such connections would surface. It wasn't until I looked at the initial image playbacks that I realized the mullions of the windows created a Mondrian-like structure within which discrete visual narratives appeared. And when we printed the work, it became apparent that the dirt on the windows was refracting the light in such a way as to give a painterly cast over the photographs. After viewing these phenomena I started seeing specific paintings as I shot and certain unconscious memories of historical work by artists such as Hopper and Vermeer seemingly guided my eye.
With The Workers series I actively courted the painting reference by not only shooting through light-distorting dirty windows again, but by formatting the images as ovals, referencing the 17th century Dutch portrait paintings of Frans Hals, among others. I used the oval format as a framing device to signify a window but also to confer a class status not usually afforded those that work with their hands.
So where we experienced the subjects in The Neighbors at leisure in their luxury apartments, here we see the worker's hands, elbows, backs and shoulders concentrating on the task at hand—building more palaces in the sky.
Will you continue to work in a similar vein or do something different —what's next?
Currently I'm working on The Birds, a series I photographed in Scandinavia earlier this year. Though unpopulated by people, it is a further exploration of that amorphous region between painting and photography.
Arne Svenson is represented by the Julie Saul Gallery. Follow Arne on Instagram.
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Chicago, Illinois –2014– As manufacturers implement lean practices, operations teams are focused on high value tasks with limited time tofocus on end-of-line labeling systems that require mechanical adjustments and frequent intervention. Responding to these needs, Videojet Technologies, a global leader in coding, marking and printing solutions, has taken an innovative approach to Print & Apply labeling LPA design with the Videojet 9550 to address, and fix, the common causes of lost productivity. This new design removes the mechanisms that frequently cause everyday operational problems, such as label jams and routinemanual adjustments. Ondrej Kruk, global business unit manager at Videojet adds "The 9550 with Direct Apply places the label onto the pack without the need for a tamp or air blast applicator, achievingthroughput of up to 150 packs per minute fortypical 4" x 6" GS1 barcode labels. This means it never misses a label, even after line build-backs,."By incorporating Intelligent Motion™ technology, the entire system is precisely and electronically controlled,targetingzero unscheduled downtime on production lines.
Manual adjustments are one of the main causes of daily operational problems, resulting in costly downtime and production loss. The direct drive system, withIntelligent Motion™ technology, feeds andplaces labels accurately even at high line speedswithout the use ofmanual adjustments,clutches or nip rollers. No adjustments means that only two operator touches are now required to manage job selection and web changeover,complemented by a collapsible mandrel to ensure quick label changes. The Direct Drive system withIntelligent Motion™ technology, unlike conventional print & apply labelers, controls the entire label pathensuring web tension is maintained from start to finish, irrespective of speed or label size.
The unique ability of the new Videojet 9550 Direct Apply system, removesthe need for complex applicatorsfor mainstream top or side label applications, reducing the number of labels being incorrectly applied or mangled during application. Requiring no factory air,the new systemis the only solution to print and directly apply labels tocases and trays at high speed.The 9550's print enginealso incorporatesIntelligent Motion™technology for precise ribbon feed and printhead control, ensuring optimum print quality and improvedperformance. Through use of a clutch-less ribbon drive, the 9550 substantially reduces ribbon waste and improves printhead life.
The trendstoward increasing retailer and regulatoryrequirementsand increasing SKU complexity is a main concern for manufacturers seeking to safeguard their operations from costly labeling errors.In order to help manufacturers improve quality and adhere to applicable standards,the 9550 comes equipped with the Videojetindustry-leading CLARiTYtouch screen interfacewhich includes intuitive job selection, comprehensive feedback and diagnostics to minimize human error. This single, easy-to-use interface provides manufacturers with built-in Code Assurance solutions that focus on getting the right label on the right case, time after time.
For more information about the Videojet 9550 LPA system, call 0870 242 1759 or visit www.videojet.co.uk.


text:
HNLMS Jan van Gelder was a  of the Royal Netherlands Navy that served in World War II.

Service history
Jan van Gelder was damaged by her own mines off Terschelling on 8 October 1939. Three men were killed, three were missing and seven were wounded. After initial repairs at Willemsoord, Den Helder, she received a new stern at Gusto, Schiedam, and was recommissioned on 17 April 1940.

During the invasion of the Netherlands by Germany in May 1940, she escorted the Dutch submarine O-13 to England. Later that month, on 29–31 May, she escorted the Dutch passenger ship Batavier II to Cherbourg, to pick up 280 Dutch troops.

Refitted and rearmed in 1940, she was assigned to serve with the British Royal Navy's 11th Minesweeping Flotilla, stationed in Milford Haven, Wales. Later in 1941 she served with the 9th Flotilla off Portland. She mainly acted as buoy ship, marking the swept channels. From October 1941, she swept acoustic mines off Harwich and the Isle of Wight. Later she was sent to Scotland and served as an escort ship with a British submarine flotilla. On 26 March 1943 she was transferred to the Royal Navy.

She was returned to the Netherlands in 1946 and was recommissioned in the Royal Netherlands Navy. She sailed for the Dutch East Indies where she served as patrol ship until 1950. After her return, she was rebuilt as boom defence vessel. Struck in 1961, she was then transferred to the Zeekadetkorps Nederland (Dutch Sea Cadets). She was assigned to the 'Jacob van Heemskerck' unit in the town of Schiedam, and moored at the same shipyard where she was launched 25 years earlier. The sea cadets removed the boilers for additional space, making the Jan van Gelder a stationary training ship ('floating clubhouse'). Because of severe leaking in the engine room, she was replaced in 1979, and scrapped.

Jan van Amstel-class minesweepers
1937 ships
World War II minesweepers of the Netherlands
Ships built by Gusto Shipyard

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Praying Mantis Perfectly Preserved In Amber Was Between 23-34 Million Years Old
An incredible natural phenomenon occurs when insects and even animals can become entombed and frozen forever in tree sap that eventually becomes amber.
An example of this is the small praying mantis in a piece of amber was sold through Heritage Auctions for $6,000 in 2016 and was found in the Dominican Republic. It was estimated that it dates back to the Oligocene period, so it is between 23 million and 33.9 million years old.
Nowadays, there are about 2,400 known species of mantises, and most of them can be found in tropical climates. However, the earliest of the praying mantis' fossils dates back to 135 million years ago, and they come from Siberia.
All members of the family Mantidae are known as mantids, while the word 'Praying Mantis' refers to any species of the family Mantidae, regardless of its origin, and if it's a Brazilian mantis or a Chinese mantis.
It is one of the rarest specimens that can be found, and in most cases, these ferocious insects are usually distorted or lacking limbs due to their fearful struggle to escape the inexorable ooze.
Yet, this one was preserved to perfection, right down to the color patterns on its slender legs, fine arm spikes, delicate antennae, and big compound eyes. A mantis has two big eyes, used for seeing movement and having depth vision, and three smaller eyes located on the middle of their head, used for detecting light.
The resin comes from the extinct tree Hymenaea protera, which is the source of Dominican amber and probably of most amber found in tropical countries. It was a ½ inch long, encased in a beautiful polished golden nugget measuring 1¾ x 1¼ x 1 inches.
It also had three large and perfectly preserved click beetles, that make it an extraordinary museum-quality specimen. As we mentioned, animals can also be preserved in this way, and last year, researchers found a baby snake on amber, 99 million years old.
Michael Caldwell, a professor in the biological sciences department at the University of Alberta in Canada, and his team named the specimen Xiaophis myanmarensis.
Amber acts as super glue, and catches everything it touches, preserving it for million years. When this baby snake was caught, it also collected the forest floor with the bugs, plants and bug poop.
Caldwell said that the snake had unique features of the top of the vertebrae that have never been seen before in other fossil snakes. It belongs to the base of the snake family tree, and to an ancient group of snakes.


Using GSAA, we discover that Jonathan Bernier has saved the Toronto Maple Leafs 18.22 goals against in 44 games this season, compared to if there was a league average goaltender in his place. That's second in the league to only Ben Bishop.
Advanced statistical knowledge in sports has increased rapidly in the last two decades. Hockey has been a step behind most other sports, but is starting to catch up with the rise of possession statistics such as the wildly popular "Corsi" percentage. The sheer volume of information that is collected now can be enough to make your head spin, but a lot of it is extremely valuable when it comes to evaluating individual performance.
When it comes to evaluating a goaltender, three statistics in particular have been looked at throughout most of history. Those three stats are wins, goals against average and save percentage. While all three categories still have some merit, they have become somewhat outdated. Wins and goals against average are better looked at as a team statistic and is actually a very poor way to evaluate an individual goaltender's performance. Even save percentage isn't perfect. It can be skewed depending on the quality of team that the goaltender plays for.
In baseball, batting average, home runs and runs batted in were the "big three" categories for years. They have been effectively replaced by percentage stats, and statistics that compare a player to a "replacement player." Essentially, if that player was replaced by a minor leaguer, would that minor league player perform better, or worse? It's called "WAR" which stands for Wins Above Replacement.
There is a relatively new statistic for hockey that has been made available by the folks at Hockey-Reference. It's similar to baseball's WAR, and it is called "GSAA" – Goals Saved Above Average. You take the league's average save percentage and apply it to the amount of shots a particular goalie has faced. You get a number of goals that the average goalie in that league would have surrendered if they faced the same number of shots as the goaltender in question. That number gets compared to the number of goals surrendered by that goaltender, and a plus/minus is created. If a goalie is in the positive, that is how many goals they have saved compared to a league-average goalie. If they are in the negative, then it is safe to assume that they are performing worse than how a league-average goaltender would perform in the same situation.
For the full list of GSAA leaders, click here.
It is a very good stat at equalizing goalies across the league, regardless of the team that they play for. For example, a goalie that has a .925 save percentage and has faced a lot more shots than average is actually playing better than a goalie that has a .930 save percentage and has faced less shots. The first goalie has faced more scoring opportunities, and has saved more goals from going in based on their quality of play.
It tells you how much a team relies on their goaltending to win games. If a team gives up a lot of shots, but their goalie is continually bailing them out, their goalie will have a very high GSAA number. Those teams are more likely to struggle if their goalie goes into a slump or gets injured. Teams that succeed despite having a goaltender that is in the middle of the pack (or worse) in GSAA are actually more stable, because if their goalie slumps or gets injured, they still have a very good chance to win using a replacement netminder.
It gives you a physical number of goals saved, rather than a percentage. It's a stat that can be very shocking. For example, Ben Bishop has saved almost 24 goals from being scored on the Tampa Bay Lightning in 44 games. A number that large will draw a lot of attention. It is a great stat to prove Bishop's worth to the Lightning. 24 goals saved is a VERY significant number.
Goalies that play more games will accumulate more goals saved. If the stat was expressed as GSAA/per 60 minutes, it would be even more accurate. You would have to turn it into a percentage, though. Only goalies that have played a certain number of games would be able to qualify.
It does not take penalty killing into account. On average this season in the NHL, goalies have seen a 4.4% drop in save percentage while on the penalty kill compared to even strength. This is a major problem for some goalies that play for a team that is constantly killing penalties. Undisciplined teams will have goalies with a lower save percentage and a lower GSAA as a result.
It does not take fatigue into account. Saves that are made after the 30 shot mark should be worth more, because goalies that face more shots than the league average will be more tired, and will make less saves due to the poor quality of the team in front of them giving up more scoring attempts.
It also does not take shot quality into account. This can be related to the number of penalties a certain team commits, or even a team's quality of defence, but that would be very difficult for any statistic to quantify.
GSAA is definitely not a perfect statistic, but it is one of the best ones available at the moment when it comes to analyzing goaltenders. It has flaws, but it is more accurate than save percentage and should become more widely used.
This is an interesting stat, is there a simple way to compute it using your own statistics? It seems like a fairly daunting task to find it out for yourself but I would like to see what it would show.
Yes, Matthew. You have to know three things: Your Shots Against, Your Saves, and the average save percentage of the league you play in. If the average save percentage is .915, you find out how many saves would be made if you stopped 91.5% of the shots you faced. Then you calculate your saves – the league average save number. There you have it!
If you don't know the league average save percentage, you can also just pick a number that you would see as being "average" in your league.
I always thought a good measure of activity would be Shots Per Minute (SPM). This would only be an additional indicator of how active a goalie is. Using your stats above you would see that the busiest goaltenders, those that faced more shots per minute of play would be Miller, Bernier and Price.
Then you can see that a similar save % was much harder to achieve for one goaltender as compared to another.
Thanks. Very interesting and it advances a much needed effort to really track and compare goal tender performance. The mathmatics is daunting however, so – is there an app for that? It would be good to incorporate another column in the Pointstreak stats. Thanks and we'll stay tuned.
This new stat is worse than save %. The argument for it don't make since.
-Not true. If Goalie A faces 10 shots and 1 slips in he will have a worse save % than a goalie who faces 15 shots and 1 slips in. Meaning the margin of error for a goalie facing less shots is higher.
-That one I can agree with, but it still won't tell you how well the goalie saw the shots or where they came from. A shot from the point with no traffic compared to a one timer across the crease with traffic. If a defensive system is playing well, the shots a goalie recieves are goingt to be easier to track, i.e. outside/bad angle with not oposing player screening.
-So I'm not great at math, but that's the same thing. A 92% save percentage is 92 saves out of 100 = 8 goals per 100 shots. Doesn't do anything.
Conclusion, another pointless stat that someone came up with. I agree with the article in the fact that, I have never been able to figure out why people ever use goals against as a goalie stat. An average of 45 shots a game is probably going to yeild a higher GAA than 25 shots a game. But, the guy getting 45 shots might just have the better save percentage.
Greg, you did make a very good point in the article that linked this one. Two goalies playing the same system should be able to use this stat. This could be used to find out who the better back up would be or even if your back-up may be better off starting.


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Permanent Life Insurance And Term Life Insurance Policy Difference Can Be Known.
Home » Commercial Vehicle » Permanent Life Insurance And Term Life Insurance Policy Difference Can Be Known.
Posted by admin on Oct 2, 2011 in Commercial Vehicle | Comments Off on Permanent Life Insurance And Term Life Insurance Policy Difference Can Be Known.
Difference between whole or universal life insurance and term life insurance policy both of them provide death benefit on the death of the insured, yet there is. Let us examine that.
For the life of the insured the whole or universal life insurance policies are valid. For a fixed term only however, term life realizes that nobody needs lifelong insurance coverage and so it is sold.
To develop the cash value the premium you pay in a term life does not buy you anything other than death benefit; but in a permanent life insurance policy, a part of the premium is diverted to a separate account.
The term life cannot offer you any investment opportunity, but since the whole amount is utilized to develop the face amount, you can have a large death benefit at a low rate consequently. But the death benefit they offer is comparatively much less contrarily, the permanent life insurance policies provide financial benefits in your lifetime only.
You should put a little more effort in selecting the right kind of life insurance policy if you actually care for your family. Read them many online articles provide detailed information about different life insurance policies. To study them carefully if you care quotes too can provide quite a lot of information. With receiving quotes of course, the process of policy purchase always starts. Always receive life insurance quote on line; that is the easiest way to do that.
Let us go back to where we started now. The right kind of policy has to be chosen which is essential. For only those, who do not have any kind of financial discipline they say that the whole or universal life is suitable. You will get a much better return you see, a term life is far cheaper than these permanent policies; if you only put in the difference in their rates in suitable investment fund.
Partially depends on you too however, how cheap the term life insurance quotes will be. You can never get the coverage at cheap rate if you are already on the wrong side of fifty. With the right body mass index to receive cheap term life insurance quotes you have to be young and healthy. You must not use tobacco in any form; your and your family's medical history should also be all right; most of all, you must apply for a traditional term life insurance policy moreover. But it is also rather expensive no medical term life insurance may be convenient.
Depends on lot of factors such as your age, gender, tobacco use, whether or not you are suffering from certain diseases as well as hereditary factors you must realize the policy prices depend mainly on the insurability of the person and the insurability. They cannot come to any definite conclusion although the insurers can have a partial picture about your insurability through medical banks and other agency reports, without the medical exam. Yes, they provide instant coverage and there is not much hassle involved in the policy purchase. However, if rates are an issue, you must avoid them at any cost.
Article by David Livingston of EQuote. For more information on cheap life insurance rates and seguros de vida sin examen medico, visit his site today.


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Q: Entity framework, dll, excel I have written dll in c# which is used by Excel (the dll is COM registered).  I have no problem connecting with Excel.  The dll retrieves data from a SQL Server database using Entity Framework 5.  If I run the dll through a console app, the dll works fine.  But when I run it through Excel (through VBA) I get a an InvalidOperationException.  The error message is "No connection string named "MegaDailyEntities' could be found in the application config file.  This occurs the first time I try to retrieve data from the database.
I ran into this problem with the console app, but then I include the following in my App.config file
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <configSections>
        <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
    </configSections>
    <entityFramework>
        <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
            <parameters>
                <parameter value="v11.0" />
            </parameters>
        </defaultConnectionFactory>
    </entityFramework>
    <connectionStrings>
        <add name="MegaDailyEntities" connectionString="metadata=res://*/MegaDaily.csdl|res://*/MegaDaily.ssdl|res://*/MegaDaily.msl;provider=System.Data.SqlClient;provider connection string="data source=CQI-Laptop1;initial catalog=MegaDaily;integrated security=True;MultipleActiveResultSets=True;App=EntityFramework"" providerName="System.Data.EntityClient" />
    </connectionStrings>
    <startup>
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
    </startup>
</configuration>

and it worked fine.
So my question is, how do I get Excel to use this connection?  Is there a config file for Excel?
Thanks

A: The reason why connection string is not found is because .config files exist only for applications (.exe) but not for additional libraries (.dll)
Excel process tries to load connection string from Excel.exe.config, instead of loading from yourlibrary.dll.config
Working solution for this is to edit your *.context.tt file (EntityFramework classes generator) and update contructor for you DbContext.
You will find something like:
public <#=code.Escape(container)#>()
        : base("name=<#=container.Name#>")
{
    ...
}

It should be possible to change it into
public <#=code.Escape(container)#>()
        : base("your EF connection string")
{
    ...
}

Or take a look how to set connection string from code

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