text:
The wave of a photon/Marking the wave, Quantum erasers

Mach-Zehnder interferometer
In a Mach-Zehnder interferometer a light beam is split by a 50% mirror in two beams (red and blue). Both beams are reflected by a mirror and cross each other. Finally each beam ends in a separate detector. In (1) each detector can detect photon from the red or blue path and no interference is measured. In (2) a second beam splitter mixes the red and blue beam. Now both detectors show interference, but cannot detect if the photon followed the red or blue path.

In the classical wave description the wave of the photon is split in two by the 50% mirror. In (1) each detector sees only one wave, so there is no interference with the other wave. In (2) both waves are mixed, so each detector sees both waves, causing interfere.

Particle-path detectors and entangled photons (Kim et al)
A high intensity laser radiates though the "red" and "blue" part of a beta barium borate crystal (BBO), which generates now and then two entangled photons with half the energy of the laser photons. These photons follow two paths by a Glan-Thompson Prism. One of the photons, the "signal" photon, goes upwards, through a lens, to the target detector D0. The other photon, the "idler" photon, goes downwards and is deflected by a prism that sends it along divergent paths, depending on whether it came from the red or blue BBO area. Beyond each path a 50% mirror acts as a beam splitter (green blocks), resulting in a 50% chance to pass through and a 50% chance to reflect to detectors D3 or D4. The photons which pass through are reflected by 100% mirrors (gray-green blocks) to the detectors D1 or D2. Where both beams cross, a 50% mirror is placed, which mixed both beams.Because of this arrangement, if the photon is recorded at detector D3 (resp. D4), it can only be a blue (resp. red) photon. If the photon is recorded at detector D1 or D2, it can be both a red or blue photon. A coincidence counter selects from D0 only those events which coincide with a chosen other detectors. This includes a delay of 8 ns to compensate for the 2.5 meter longer path to the other detectors. the result was:

 * When events were counted which coincided with D3 or D4, there was no interference.
 * When events were counted which coincided with D1 or D2, there was an interference pattern.

With classical wave physics a set of photons is emitted in the red or blue area of the BBO, no in both at the same time. There with ill be only one wave, to interfere with D3 or D4. But the interference with D1 or D2 cannot be explained classical, because of the absence of two waves.

Linear polarizers
In this experiment both waves are differently (perpendicular) polarized. Then no interference pattern is visible. A polariser in front of the detector, with its axis 45° to the other polarisers, erases this information, causing the interference pattern to reappear.

Classical this effect is know as the Fresnel and Araglaws laws, which state that perpendicular polarization does not interfere. The 45° polarisers force both perpendicular polarizations to become parallel polarizations, which can interfere. Also classical calculation gives the same result.

===Circular polarizers and entangled photons (Walborn et al) === A beta barium borate (BBO) crystal, radiated by a strong laser, will generating now and then two entangled photons. One photon (yellow) goes through a double slit to signal detector Ds, with rotating polarizer Q1 or Q2 in each path. Q1 and Q2 axis are pendicular, producing a opposite rotating polarization. The other photon (green) goes to detector Dp, with a linear polarizer cube POL in the path. Only photons in Ds are registered which coincidence with photons in Dp. Dp is situated closer to the BBO then Ds, so photons are first detected by Dp. The results were:

 * 1) Without Q1/Q2 and POL there was an interference pattern in Ds
 * 2) With Q1/Q2 there was no interference.
 * 3) With Q1/Q2 and POL, adjusted on the Q1 fast axis, there was interference.
 * 4) With Q1/Q2 and POL, adjusted on the Q2 fast axis, there was interference, but 180º shifted with 3.
 * 5) 1-4 with Dp on a larger distance then Ds gives the same result. This is called a delayed eraser, because the photon in Dp is detected later then in Ds

In the classical wave description Q1 and Q2 are quarter-wave plates which have perpendicular a "fast" and "slow" axis. The slow axis has a π/2 phase delay compared to the fast axis. Q1 and Q2 are mounted mutually perpendicular. In setup 2 the incoming photon has a random polarization (shown as red) which can be resolved into two waves, parallel (green) and perpendicular (blue) to the optical axis of the waveplate (see figure). Depending on the axis the wave on x or y are delayed π/2. At the detector the x and y vectors interfere (add up) and can be composed to one vector. Calculation shows that the probability is:

P = 0.5 - 0.5cos2αsinφ

 * A:  If α = 0 (incoming polarisation parallel to the fast axis of Q1) then P = 0.5 - 0.5sinφ
 * B:  If α = π/2 (incoming polarisation parallel to the fast axis of Q2) then P = 0.5 + 0.5sinφ
 * C:  If α = random then integrating α from 0 to 2π and normalised gives P = 1. This of course the same as A + B: P = 0.5 - 0.5sinφ + 0.5 + 0.5sinφ = 1

If the incoming polarization is parallel to a fast axis of a wave plate a φ interference pattern is visible on the detector. Between A and B there is a phase difference of π. If α is random then there is no φ pattern. C can be explained as having no interference pattern or being the sum of two interference pattern A and B which have a phase difference of π, which when added does not show an pattern. According classical rules both explanations are right. Also the Walborn article mentions that the result of setup 2 is the sum of setup 3 and 4.

In the experiment the incoming photon is the signal photon of a BBO. In setup 2 the polarization is random, so the measured result is as C above. The BBO emits an entanglement photon pair with mutually perpendicular polarization. According the article in set-up 3 POL was set to the angle of the fast axis of Q1. So the idler photons which passed through must have a signal photon with perpendicular polarisation, so parallel to the fast axis of Q2. These will show an interface pattern according B, which confirms with the measured result. In set-up 3 POL was rotated π/2, which gives the result of A. In other words, Dp detects only idler photons with a signal photon which polarization parallel to Q1 or Q2, which show an interference pattern according A or B. Dp selects those photons by coincidence from the output of Ds.

In above formulation the time the idler is detected in Dp is not important (as long as delays are used to compensate for path length difference). The "delayed" effect is in the classical wave explanation the effect that POL determines the polarisation of the signal wave before Q1/Q2, although POL is position on a much larger distance of the BBO then Q1/Q2.

Wheeler's astronomical experiment
Wheeler's delayed choice experiment is a thought experiment in which the type of detector (particle or wave) is changed after a photon passes the double slit. In a second version the scale is magnified to astronomical dimensions: a photon has originated from a star and its path is bent by an intervening galaxy, so that it could arrive at a detector on earth by two different paths images. The detector could be a screen (as wave detector) or two telescopes, each focused to either side of the black hole. In both versions Wheeler expected that the screen will measure an interference pattern, while two telescopes will observe the photon only in one of them, without interference. If the outputs of both telescopes are optically combined, the interference pattern would be back, but losing the information of the path of the photon.

This result follows the classical waves: interference is caused by adding two waves during detection. If a telescope is directed at one wave, so no interference. If both telescopes are optically combined there are two waves again, which will interfere. The experiment shows that a photon always keeps full wave- and particle properties, until they combine during absorption. . The first version has been confirmed in practice by Jacques e.a. with a Mach-Zender interferometer. The astronomical version is not yet done and probably too difficult in practice, because for an interference pattern the photons must be coherent when they arrive on earth, after such a long time.


text:
The wave of a photon/Other experiments

==Hong–Ou–Mandel Interferometer == The Hong-Ou-Mandel interferometer is a variant of the Mach-Zehnder interferometer in which two simultaneous photons are compared. A 351 nm laser radiates a KDP crystal, which because of SPDC emits now and then two entangled photons of about 702 nm. The KDP is propably a type I, in which both photons have the same polarization and the same phase. Both waves are mixed in a 50% reflecting mirror, filtered by a bandpass interference filter IF and detected with a coincidence of 7.2 ns.

It is supposed that this beam splitter is a glass plate with reflector on one side, causing (only) the reflection from the normal input having a phase shift of π. All other have no phase shift. At the detectors the waves are: Iu = 0.5sin(π+ωt+φ/2) + 0.5sinαsin(ωt-φ/2) and Il = 0.5sin(ωt+φ/2) + 0.5sinαsin(ωt-φ/2). With an ideal bandwidth filter d = Δω/ω, the probability is calculated:

Pu = 0.5 - 0.5cos(4πΔx/λ) sin(πd(2k+2Δx/λ)) / πd(2k+2Δx/λ) and Pl = 0.5 + 0.5cos(4πΔx/λ) sin(πd(2k+2Δx/λ)) / πd(2k+2Δx/λ)

These formula predicts the result of the measurement if the cosine term is ignored and k = 0. Then the formula will be:

Pu = 0.5 - 0.5sin(πd2Δx/λ) / πd2Δx/λ

Pl = 0.5 + 0.5sin(πd2Δx/λ) / πd2Δx/λ

coincident: P = Pu * Pl

In the experiment ω = 2πc/702nm = 2.7 1015. The bandwidth filter is 3 1013, d = 3 1013 / 2.7 1015 = 0.011. Then FWHM = 113 μm.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: The wave of a photon/Other experiments


text:
The wave of a photon/Calculations

General
Propability P = (ʃ(I2)dωt)/2π, from 0-2π

ʃsin2(nωt+φ)dωt, from 0-2π = ʃcos2(nωt+φ)dωt = π (if n = integer)

Double slit
With interference of two waves sin(ωt+φ1) and sin(ωt+φ2)

The result is I = √(a12 + a22 + 2a1a2cos(φ1-φ2)) sin(ωt+φ)

Propability P = ʃ(I2)dωt, from 0-2π = (a12 + a22 + 2a1a2cos(φ1-φ2) ʃsin2(ωt+φ)dωt = (a12 + a22 +  2a1a2cos(φ1-φ2)π

If a1 = a2 = 1 and φ1-φ2 = φ: P = 2π(1+cosφ). Normalised to 1: P = 0.5+0.5cosφ

If a1 = 0.5, a2 = 1 and φ1-φ2 = φ: P = π(1.25+0.5cosφ). Normalised to above: P = 0.5+0.2cosφ

Linear polarizer
x and y are parallel to the polarisers axis, both polarisers are mounted perpendicular, α is the angle of incoming polarization, φ is the phase difference caused by path length difference

The two waves are x = cosαsin(ωt+φ/2) and y = sinαsin(ωt-φ/2)

Combined: I = √(x2 + y2)

Propability P = ʃ(I2)dωt, from 0-2π = ʃ(x2 + y2)dωt = cos2αʃsin2(ωt+φ/2)dωt + sin2αʃsin2(ωt-φ/2)dωt = (cos2α + sin2α)π = π. Normalised: P = 1, so no φ interference pattern.

Walborn
x and y are chosen parallel to the axis the quarter-wave plates. Both plates are mounted perpendicular, α is the angle of incoming polarization, φ is the phase difference caused by path length difference

x = x2 + x1 = cosαsin(ωt-π/2-φ/2) + cosαsin(ωt+φ/2) = 2cosαcos(π/4+φ/2)sin(ωt-π/4)

y = y2 + y1 = sinαsin(ωt-φ/2) + sinαsin(ωt-π/2+φ/2) = 2sinαcos(π/4-φ/2)sin(ωt-π/4)

Combined: I = √(x2 + y2)

Propability P = ʃ(I2)dωt, from 0-2π = ʃ(x2 + y2)dωt = (4cos2αcos2(π/4+φ/2) + 4sin2αcos2(π/4-φ/2))ʃsin2(ωt-π/4))dωt = 4(cos2α (0.5+0.5cos(π/2+φ)) + sin2α (0.5+0.5cos(π/2-φ))π = 2π(cos2α + sin2α + cos2αcos(π/2+φ) + sin2αcos(π/2-φ)) = 2π(1 - cos2αsin(φ) + sin2αsin(φ)) = 2π(1 + (-cos2α + 1 - cos2α)sin(φ)) = 2π(1 + (1-2cos2α)sinφ) = 2π(1 + (1 - 2(0.5+0.5cos2α))sinφ) = 2π(1 - cos2αsinφ)

Normalised: P = 0.5 - 0.5cos2αsinφ

If α = random: P = 0.5ʃ(1-cos2αsinφ)dα from 0 to 2π = |α - 0.5sin2αsinφ| = (2π - 0 - 0 + 0) = 2π. Normalised: P = 1

Hong–Ou–Mandel
It is supposed that the beam splitter is a glass plate with reflector on one side, causing (only) the reflection from the normal input having a phase shift of π. Both photons start in the KDP with the same phase. Then at the upper (u) and lower (l) detector the waves are:

Iu = -0.5sin(ωt+φ/2) + 0.5sin(ωt-φ/2) = -cosωtsin(φ/2) and Il = 0.5sin(ωt+φ/2) + 0.5sin(ωt-φ/2) = sinωtcos(φ/2)

Probability Pu = ʃ(I2)dωt), from 0-2π = sin2(φ/2)ʃcos2ωtdωt = (0.5-0.5cosφ)π and Pl = cos2(φ/2)ʃsin2ωtdωt = (0.5+0.5cosφ)π.

Normalised: Pu = (0.5 - 0.5cosφ) and Pl = (0.5 + 0.5cosφ)

and coincident: P = Pu * Pl = (0.5 - 0.5cosφ) (0.5 + 0.5cosφ) = 0.25 - 0.25cos2φ. Normalised: P = 0.5 - 0.5cos2φ

Phase shift The phase shift between both waves can be caused by the different wavelength (1+p) and the displacement of the beam splitter causing a Δt in only one path. If t = time between the KDP and Du, then the phase difference can be written as:

φ = φ2 - φ1 = ω(1+p)(t+Δt) + π - ω(1-p)t = ωt + ωpt + ωΔt + ωpΔt - ωt + ωpt + π = 2ωpt + ωΔt + ωpΔt + π = ωΔt + ωp(2t+Δt) + π

This is the formula for a fixed p, but in practice there is a mix of different wave lengths. With an ideal bandwidth filter Pu is equal within p = -d/2 - +d/2 (and zero outside). When used in the formula of Pu above:

Pu = ʃ (0.5 - 0.5cos(π + ωΔt+ωp(2t+Δt)) dp / d from -d/2 - +d/2  = ʃ (0.5 + 0.5cos(π + ωΔt+ωp(2t+Δt)) dp / d

= 0.5 | p - sin(ωΔt+ωp(2t+Δt)) / ω(2t+Δt) | / d

= 0.5(d/2 - sin(ωΔt+ωd(2t+Δt/2))/ω(2t+Δt) + d/2 - sin(ωΔt-ωd(2t+Δt)/2)/ω(2t+Δt) ) / d

= 0.5(1 - 2cos(ωΔt) sin(ωd(2t+Δt)/2) / ωd(2t+Δt)

= 0.5 - cos(ωΔt) sin(ωd(2t+Δt)/2)) / ωd(2t+Δt)

ω = 2πf = 2π/T = 2πc/λ, so T = λ/c, Δt = 2Δx/c (Δx has double effect), so Δt/T = 2Δx/λ. Suppose t = kλ. Then:

= 0.5 - cos(2πc2Δx/λc) sin(2πd(2kT+Δt)/2T)) / (2πd(2kT+Δt)/T)

Pu = 0.5 - 0.5cos(4πΔx/λ) sin(πd(2k+2Δx/λ)) / πd(2k+2Δx/λ)

and Pl = 0.5 - 0.5cos(4πΔx/λ) sin(πd(2k+2Δx/λ)) / πd(2k+2Δx/λ)

and coincident: P = Pu * Pl

The general form of the second sinus part is:

ΔxFWHM = cΔt/2 = 0,00148 λ/d = 0,000443 λ/d μm (λ in nm)

title: The wave of a photon/Calculations


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Infrastructure Past, Present, and Future Casebook/Hoover Dam

This casebook is a case study on the Hoover Dam by Leul Lakew, Abrar Samimi-Darzi, Cooper Gandy, and Karen Herrera as part of the Infrastructure Past, Present and Future: GOVT 490-004 (Synthesis Seminar for Policy & Government) / CEIE 499-001 (Special Topics in Civil Engineering) Fall 2021 capstone course at George Mason University 's Schar School of Policy and Government and the Volgenau School of Engineering Sid and Reva Dewberry Department of Civil, Environmental, and Infrastructure Engineering. Modeled after the Transportation Systems Casebook. Under the instruction of Prof. Jonathan Gifford.

'''[References - Part 1
 * 1) Background information on the Salton Sea. (n.d.). Retrieved November 17, 2021, from https://wildlife.ca.gov/Regions/6/Salton-Sea-Program/Background

 * 1) Bureau of Reclamation, L. (n.d.). Hoover dam. Retrieved November 17, 2021, from https://www.usbr.gov/lc/hooverdam/faqs/powerfaq.html#:~:text=Hoover%20Dam%20generates%2C%20on%20average,one%20of%20the%20country's%20largest.

 * 1) Bureau of Reclamation, L. (n.d.). Hoover dam. Retrieved November 17, 2021, from https://www.usbr.gov/lc/hooverdam/history/articles/naming.html

 * 1) Bureau of Reclamation, L. (n.d.). Hoover dam. Retrieved November 17, 2021, from https://www.usbr.gov/lc/hooverdam/history/essays/fatal.html

 * 1) Colorado River Compact. (n.d.). Retrieved November 17, 2021, from https://www.watereducation.org/aquapedia-background/colorado-river-compact

 * 1) "The greatest dam in the world": Building Hoover Dam (teaching with historic places) (U.S. National Park Service). (n.d.). Retrieved November 17, 2021, from https://www.nps.gov/articles/-the-greatest-dam-in-the-world-building-hoover-dam-teaching-with-historic-places.htm

 * 1) History of the Phoenix Canal System. (n.d.). Retrieved November 17, 2021, from https://www.srpnet.com/water/canals/history.aspx

 * 1) History.com Editors. (2010, April 14). Hoover dam. Retrieved November 17, 2021, from https://www.history.com/topics/great-depression/hoover-dam

 * 1) Hoover dam. (n.d.). Retrieved November 17, 2021, from http://www.waterencyclopedia.com/Ge-Hy/Hoover-Dam.html#:~:text=The%20main%20reason%20for%20building,to%20finance%20more%20water%20projects.

 * 1) Hoover dam. (n.d.). Retrieved November 17, 2021, from https://www.britannica.com/topic/Hoover-Dam

 * 1) Rasmussen, P. (2020, July 15). What if the Hoover Dam Broke? Retrieved November 17, 2021, from https://science.howstuffworks.com/engineering/structural/hoover-dam-broke.htm#:~:text=Damage%20to%20the%20Dam&text=If%20catastrophe%20struck%20the%20Hoover,foot%20(30%20centimeters)%20deep.&text=Approximately%2025%20million%20people%20depend%20on%20water%20from%20Lake%20Mead.,-The%20reservoir%20supplies

 * 1) “The American Experience | Hoover Dam | Timeline.” PBS, Public Broadcasting Service, 1996, http://www.shoppbs.pbs.org/wgbh/amex/hoover/timeline/index.html.

 * 1) Carlowicz, Michael, and Kathryn Hansen. “Lake Mead Drops to a Record Low.” NASA, NASA, 22 Aug. 2021, https://earthobservatory.nasa.gov/images/148758/lake-mead-drops-to-a-record-low.

 * 1) “John Wesley Powell Biography.” John Wesley Powell, https://www.usgs.gov/staff-profiles/john-wesley-powell?qt-staff_profile_science_products=3#qt-staff_profile_science_products.

 * 1) TheB1MLtd. “Building the Hoover Dam.” YouTube, YouTube, 15 Aug. 2018, https://www.youtube.com/watch?v=n9Gy_1Ppw5U.

 * 1) History.com Editors. (2010, April 14). Hoover dam. History.com. Retrieved November 16, 2021, from https://www.history.com/topics/great-depression/hoover-dam.

 * 1) History.com Editors. (2010, April 14). Hoover dam. History.com. Retrieved November 16, 2021, from https://www.history.com/topics/great-depression/hoover-dam.

 * 1) Impact of the Hoover Dam. environmentalpsychology. (n.d.). Retrieved November 17, 2021, from https://environmentalpsychology.jimdofree.com/history-az-and-phoenix-1/impact-of-the-hoover-dam/.

 * 1) Bureau of Reclamation, L. C. R. W. T. (n.d.). Hoover dam. Hoover Dam | Bureau of Reclamation. Retrieved November 17, 2021, from https://www.usbr.gov/lc/hooverdam/.

]'''
 * 1) Guardian News and Media. (2021, July 13). Severe drought threatens Hoover Dam Reservoir – and water for US west. The Guardian. Retrieved November 17, 2021, from https://www.theguardian.com/us-news/2021/jul/13/hoover-dam-lake-mead-severe-drought-us-west.

Summary
The Hoover Dam (formerly know as the Boulder Dam) is located in Clark County, Nevada, and Mohave County, Arizona in the United States. Originally proposed in 1922 by Arthur Powell Davis, the Hoover Dam was meant to prevent flooding, divert water to budding communities, and generate hydroelectric power. The proposition for the dam would be authorized in 1928 by president Coolidge, signed in as “The Boulder Canyon Project Act” it appropriated an estimated $165 million for the project. Being built in the Black Canyon of the Colorado river the Hoover Dam would begin construction in 1931, the Dam would be built by Six Companies Inc. At the time of construction, the Hoover Dam would be both the largest concrete structure and dam ever built. With construction taking place during the Great Depression the construction of the dam attracted tens of thousands of workers to travel to Nevada in order to find work, many of them going to; at the time; the small city of Las Vegas.

The construction of the dam was surrounded by controversy and pushback. Due to the nature and sheer size of the project, many of the techniques used during construction were experimental and untested. With a price tag of $165 million attached to it, many policymakers were hesitant about the project, worrying about the potential failure of the dam and that the diverted water would go almost exclusively to California. This problem would be solved by then-Secretary of Commerce Herbert Hoover who created the 1922 Colorado River Compact which divided the water proportionally among the seven states affected by the dam. Several years after the Colorado River Compact was signed construction of the dam would begin.

Six Companies, Inc.
The Hoover Dam was built by the Six Companies, Inc. which was a joint venture made up of eight companies, the first five of which were Morrison-Knudsen Co., Utah Construction Co., J. F. Shea Co., Pacific Bridge Co., MacDonald & Kahn Ltd.; the next three companies that make up the Six Companies are [Another Joint Venture] Company consisting of W. A. Bechtel Co., Henry J. Kaiser Co., Ltd. (also known as Kaiser Paving Co. Ltd.), and the Warren Brothers Company (also known as the Warren Brothers of Massachusetts).

 * 1) Morrison-Knudsen Co. (Morrison & Knudsen Co.): was a construction company headquartered in Boise, Idaho, founded by Harry Morrison and Morris Knudsen.
 * 2) Utah Construction Co. (Utah Construction Company): was a construction company headquartered in Ogden, Utah.
 * 3) * Two of its key leaders Edmund O. Wattis and William H. Wattis took a leading role in the creating the organizational structure and incorporation of the Six Companies Joint Venture.
 * 4) J. F. Shea Co.: is a construction company that at the time of the Hoover Dam's construction was based out of Portland, Oregon.
 * 5) Pacific Bridge Co. (Pacific Bridge Company): was an engineering firm and construction company based out of Portland, Oregon.
 * 6) MacDonald & Kahn Ltd. (MacDonald & Kahn Construction Co.): is a construction company headquartered in San Francisco, California
 * 7) [Another Joint Venture] Company (due to the companies not having enough money to enter as individual partners to the Six Companies, they combined their resources to qualify):
 * 8) W. A. Bechtel Co.: is an infrastructure construction, engineering, and energy company that which at the time of the construction of the Hoover Dam was based in San Francisco, California but its successor corporation has since relocated its headquarters to Reston, Virginia.
 * 9) Henry J. Kaiser Co., Ltd. (also known as Kaiser Paving Co. Ltd.): was a road paving and construction company originally operating in Vancouver, British Columbia (Canada) and Washington State (United States), but by the start of the Hoover Dam construction it had already relocated to Oakland, California (United States).
 * 10) Warren Brothers Company (also known as the Warren Brothers of Massachusetts): was coal tar, asphalt, and pavement producing company based out of Boston, Massachusetts.
 * 1) [Another Joint Venture] Company (due to the companies not having enough money to enter as individual partners to the Six Companies, they combined their resources to qualify):
 * 2) W. A. Bechtel Co.: is an infrastructure construction, engineering, and energy company that which at the time of the construction of the Hoover Dam was based in San Francisco, California but its successor corporation has since relocated its headquarters to Reston, Virginia.
 * 3) Henry J. Kaiser Co., Ltd. (also known as Kaiser Paving Co. Ltd.): was a road paving and construction company originally operating in Vancouver, British Columbia (Canada) and Washington State (United States), but by the start of the Hoover Dam construction it had already relocated to Oakland, California (United States).
 * 4) Warren Brothers Company (also known as the Warren Brothers of Massachusetts): was coal tar, asphalt, and pavement producing company based out of Boston, Massachusetts.

Unified Structure of the Six Companies Joint Venture

 * Frank T. Crowe, a civil engineer, former General Superintendent of Construction of the United States Reclamation Service (now knows as the Bureau of Reclamation), at the time employed by Morrison-Knudsen Co. was designated the (Six Companies) joint venture's lead General Superintendent for Hoover Dam due to his prior technical experience in dam building and water reclamation.
 * Henry John Kaiser of Henry J. Kaiser Co., Ltd., was one of two architects who designed the Hoover Dam.
 * Gordon Bernie Kaufmann, was one of two architects who designed the Hoover Dam.

United States Federal Government
The Federal Government of the United States of America played a key role in the building of the Hoover Dam and related Boulder Canyon Projects dealing with the Colorado River System and Colorado River Basin. The United States Government is also the current owner of dam.

 * United States Congress
 * Boulder Canyon Project Act of 1928, introduced by Senator Hiram Johnson (R-CA) and Representative Phil Swing (R, CA-11) was the law that commissioned the construction of a dam and appropriated money designated for the Department of the Interior to hire a firm or firms to construct the Boulder Dam  (now known as the Hoover Dam)
 * Executive Office of the President of the United States: Calvin Coolidge, President of the United States, signs the Boulder Canyon Project Act of 1928 into law.
 * Department of the Interior (DOI): was the lead government department that handled the government side of planning the Boulder Canyon Project
 * United States Bureau of Reclamation: is the agency within the Department of the Interior that commissioned the bid looking for companies to that would build the dam, it eventually chose the joint venture known as the Six Companies, Inc.. The Bureau of Reclamation is currently the operator of the Hoover Dam.
 * United States Geological Survey (USGS):
 * Arthur P. Davis (Arthur Powell Davis), one of the first people to propose the building of a dam on the Colorado River.

Signatories to the Colorado River Compact of 1922
The Colorado River Compact of 1922 is an interstate compact between seven Colorado River Basin states and the United States Government that deals with the sharing of water resources between the states relating to the Colorado River on which the Boulder Dam (and other Boulder Canyon Projects) are built on.

 * State of Arizona: represented by Commissioner W.S. Norviel
 * State of California: represented by Commissioner W.F. McClure
 * State of Colorado: represented by Commissioner Delph E. Carpenter
 * State of Nevada: represented by Commissioner J.G. Scrugham
 * State of New Mexico: represented by Commissioner Stephen B. Davis, Jr.
 * State of Utah: represented by Commissioner R.E. Caldwell
 * State of Wyoming: represented by Commissioner Frank C. Emerson
 * United States of America (U.S. Federal Government): represented by Herbert Hoover as Representative of the United States Government  in an appointed position and was simultaneously holding the position of Secretary of Commerce - Department of Commerce (he later becomes a President of the United States).

Timeline of Events
Timeline of events:

May 1869 - Major John Wesley Powell (a one-armed Civil War veteran, and Director, U.S. Geological Survey (USGS)) makes his first recorded trip through the Grand Canyon and down the length of the Colorado River to record topography information for public use/intel.

April 1902 - President Theodore Roosevelt signs the Reclamation Act. Reclamation Service engineers begin investigating the Colorado River for possible uses.

March 1905 -  Rains cause the Colorado River to flood into the Imperial Valley, creating an inland sea across a hundred and fifty square miles. About $3 million in damages were done before the water levels reached normal.

April 1920 - Congress passes the Kinkaid Act authorizing the Secretary of Interior to investigate the Imperial Valley inland sea formation.

February 1922 - Arthur P. Davis (responding to congress regarding the Kinkaid Act. after his investigation) proposed the construction of a high dam on the Colorado River. He stated the government could recoup the cost of construction by selling the electric power generated by the dam to the cities in Southern California.

December 1928 - The Boulder Canyon Project Act, introduced by Senator Hiram Johnson and Representative Phil Swing, both of California, passes in the House and Senate and is signed by President Calvin Coolidge.

June 1929 - Herbert Hoover takes charge of negotiations as six of seven basin states approves the Colorado River Compact. The basin states include Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming. Arizona did not approve the dam construction.

March 1931 - The Bureau of Reclamation opens bids for the construction of the dam. The winning bid was $48,890,995 to a private joint venture made of 6 renowned construction and design firms.

November 1932 - November: The Colorado River is diverted around the dam site.

June 1933 - First concrete is poured at Hoover Dam site.

February 1935 - The Hoover Dam starts impounding water in Lake Mead.

May 1935 - The last concrete is poured at the dam site.

September 1935 - President Franklin D. Roosevelt attends and speaks at the dedication of Boulder (Hoover) Dam.

March 1947 - House Resolution 140, officially declaring that the dam at Boulder Canyon be named Hoover Dam, for former President Herbert Hoover, is introduced to Congress. It is passed two days later, moves on to be approved in the Senate.

April 1947 - President Harry S. Truman signs a resolution officially declaring that the dam at Boulder Canyon be named Hoover Dam.

Present-day - The water level in the largest reservoir of the United States (Lake Meade) is the lowest it has ever been. Starting 2022, water allocations would be cut over the next year. The biggest cut will come to Arizona, 8 percent.

Risk Allocation
Being the biggest concrete structure of the time the Hoover Dam had a lot of risks involved in its construction. There was a significant amount of risk placed on the government, which had appropriated $165 million or $2.6 billion today. As previously mentioned a lot of the construction methods used for the Hoover Dam were experimental and largely untested. This put a lot of pressure on the government as if this project failed there would be a lot of negative attention put on them, and when combined with the upcoming depression would have shifted public perception against the government.

The further risk was involved with the 7 states who stood to benefit from the Dam. As if the dam failed many of the cities that formed around the river likely wouldn’t have prospered if the dam failed and would have hurt the development of the southwest. Without the Dam, the lack of irrigation water in these cities would devastate the farming industry in these areas. Even there is the risk of the dam breaking. If the Dam were to break more than 3.5 trillion gallons of water would set loose and cause massive damage to everything in its path. And all of the cities that rely on the water from the dam would dry up and suffer from massive droughts.

During its construction, there were a lot of risks put onto the workers who had to construct the dam. Beyond the risks that come with building a dam, due to the lack of tested construction techniques and bad weather, an official count stated that 96  workers died during construction. Further deaths that weren’t included in the official counts were deaths by pneumonia, heatstroke, or other deaths caused by things not immediately related to the Dam.

Policy and Technical Issues
 Geology

The beginning to the creation of the Hoover Dam involved the diversion of tunnels, these tunnels served as waterway sources. Due to so many rocks being in the way, engineers had to use dynamites in certain sections to remove the rocks. This project was created due to its engineering and with the help of workers. From this point on, workers had to then shovel 382 cubic meters of deposits to reach the bedrock layer. On June 6, 1933, concrete was applied to the base of the dam. Then again on May 29, 1935, another layer of concrete was applied to finish this portion of the project. This was one of the most important things that led to the building of the Hoover Dam but was a challenge that the engineers faced. The use of concrete would take too long to dry which would lead to the project being delayed by years. The solution to this problem was to use rows and columns and using pumps that would transfer cold water through pipes. This was a success since they were able to build the dam 2 years before its expected built time.

The Dam was created in interlocking blocks, the biggest blocks measured at 25 x 60 feet, and the smallest block measured at 25 x 25 feet. The engineers had to become creative as to how they chose to deliver the concrete. They decided to use buckets to transfer the concrete into the blocks. From this point on, “Pullers '' would pack the concrete in place. This was an important part to the project, since if done wrong air pockets could later form.

 Economic

In 1922 the Federal director Arthur Powell Davis designed a plan to propose to congress called the “ Boulder Canyon Project” to propose to congress. This plan indicated that with the benefits to building the dam would include flooding control, irrigation, it would incorporate the use and sale of hydroelectric power. Congress was hesitant to sign off on the project due to it costing nearly $165 million dollars. Something that helped the Hoover Dam be built was The Colorado River Compact, which was created in 1922 by Herbert Hoover. This made sure that the water was dispersed evenly between the states of Arizona, New Mexico, Utah, Colorado, Wyoming, Nevada, and California. Due to the contribution of the president in December 1928, the Hoover Dam was named after the president.

The Hoover Dam faced economic issues due to the time frame. The Hoover Dam was built during the Great Depression, which made it difficult to fund and workers were needed. In order to solve this problem, the state of Nevada built 5,000 houses for the workers in Boulder City. This became an incentive for many jobless men facing difficulties during the Great Depression. The city had no elected officials and was run by the U.S by the U.S Bureau of Reclamation. To bring revenue the construction of the Boulder Dam hotel had also been done. This hotel was used to host events and have important political figures come and bring awareness to the Dam.

 Environment

The construction of the Dam has brought negative impacts to the environment. For starters, the Dam has disturbed the aquatic life and ecosystem. For starters, it has led to the destruction of many habitats. This has led to water flow direction changing drastically, which has led to an increase in sediments into the water. The Dam has lowered the water temperature and due to this many fish have died. Studies have stated that 76% of the wildlife population has been lost. Dams have also been linked to the destruction of many ecosystems. There are raising concerts due to the water drought that has been occurring throughout the years. The water level has dropped 1,071.56 feet and has raised some concerns. Due to the drought, many farmers have been affected and have abandoned their farms.

 Water Rights:

In the 1890’s water stopped flowing down the Hila River and was now being distributed to other areas to help local farmers, settlers etc. Many of the Native Americans were left with no water, which affected their crop growth. In 1908 this went to court and the supreme court was not able to make any changes to this. In order for the Hoover Dam to be built, they had to include providing a water source for the Pima tribe. They came to an agreement which later on ended being one of the reasons as to how the Dam was built. Sadly, nothing really changed and the tribe was not getting enough water. As a result of this, they were not able to economically grow and many died. Many believe that the building of the Dam killed more than 500 Native Americans. Arizona ended up benefiting from the water source the dam was able to provide.

Narrative of the Case
Background During the late 1890s, the United States was trying to develop the southwest, and the Colorado River was seen as an ideal source of water for budding cities. Initial attempts to use the river's resources were done by creating a canal to divert the water for irrigation purposes. While the canal did provide enough water to encourage settlement of the surrounding valley, the canal would soon prove to be too costly to maintain and operate and would eventually breach and flow into the Salton Sink, filling it up creating the Salton Sea. [1] In 1902 the Edison Electric Company would survey the river in hopes of creating a hydroelectric dam, but due to technological limits of the time, the project would end up falling through. However, Arthur Powell Davis would take that idea and expand upon it, proposing what would eventually become the Hoover Dam. After his initial proposal was rejected in 1922, Davis would work with the Bureau of Reclamation (BOR) and would create a new report suggesting to build a dam on the Colorado River at Boulder Canyon for flood control and hydroelectric power generation. Despite initially being called the Boulder Canyon Project, the dam would end up being constructed in Black Canyon after the BOR investigated the site and found Black Canyon to have the ideal conditions for construction. The Hoover Dam would be the victim of immense scrutiny and criticism, as the states involved were worried that the water and power generated by the Dam wouldn’t be split equally and the flourishing California would reap most of the benefits. In order to relieve this criticism Delph Carpenter; a Colorado Attorney would propose that the seven states (Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming) should form an interstate compact. After meeting with then-Secretary of Commerce Herbert Hoover, the Colorado River Compact would be signed in November of 1922. [5] Even with the Colorado River Compact, the dam would suffer heavy scrutiny, especially after the failure of St. Francis Dam in California which was similar in design to what the Hoover Dam was proposed to be. After this incident congress issued a board of engineers to review the dam, they would find the project feasible but still cautioned them to be constructed with great care. On December 21, 1928, President Coolidge would sign the bill that authorized the Boulder Canyon Project Act, appropriating an estimated $165 million for the project. A consortium called Six Companies Inc. would eventually win the bid to construct the dam.

 Construction

Since the dam needs to be constructed on a dry riverbed, the Colorado River water had to be diverted first. Four, 56 feet wide diversion tunnels were built (two on each side of the river) by blasting through the canyon using dynamite. Then workers used hammers to further break down rocks from the canyon. Then they used the excavated rocks to create cofferdams to force the water flow into the diversion tunnels.

Once the dry riverbed was exposed, the workers had to smooth the canyon surface to prevent leaks and allow the installation of the designed dam. The Hoover Dam uses a gravity-arch design which enables it to stay in place using the weight of its concrete and the weight of the water it holds, forcing it into the canyon floor and walls, which is why it is important for the surfaces of the canyon to be smooth. The concept of hardhats was also invented during this phase of the Hoover Dam’s construction.

If the entire dam’s concrete was poured in a single pour, the concrete would dry for 125 years and would also break under its own weight. So the dam was divided into several rectangular moulded sections. The moulds were fitted with steel pipes that carried river water through them so the concrete would cure faster. Once that section cured, they built a mould section above it using the same method until the entire wall of the dam was built. As the wall got taller, it got harder to get concrete up to where it had to be. So they designed suspension cables which carried buckets of concrete above. Almost 90 million cubic feet of concrete was used to build the dam. This was the largest concrete structure that had ever been built. The 726 feet high dam was complete and the diversion tunnels were sealed shut, creating the reservoir we know today as Lake Meade. The power plant component of the structure was constructed during the structure of the main dam. The hydroelectric facility produces 4.2 billion kilowatt-hours.

 Impact and Operations

Today, the Hoover Dam is owned by the United States Government and is operated by the United States Bureau of Reclamation. The Hoover Dam brought an innovative way of generating water known as Hydropower. Hydropower helped energize many mills and factories. The creation of Hydropower also helped many farmers since now they would have a water source. The Dam became not only the biggest project to be built but also became the largest Electric power. During this time period, this project helped provide jobs at a time where it was really needed. The Hoover Dam also brought attraction to the West and increased tourism, ultimately leading to an increase of both social and economic growth. Currently the Hoover Dam produces 4 billion kilowatt-hours per year and for electrical power it serves the states of Nevada, Arizona, and California.

Discussion Questions
What can we do to combat the drought that is threatening the Hoover Dam and bring the water level back up to its original state?

If the Hoover Dam does dry up, what would be a viable alternative to provide the states that rely on it with new power and water?

Without the Hoover Dam, how do you think the American Southwest would have developed?

Lesson Learned / Takeaways
1.	Using federal funding to pay for domestic infrastructure, which generates revenue (in this case generation of electricity), is a very low risk investment of federal funds and has high long-term return. By 1987, the cost of construction of the Hoover Dam was paid back to federal funds with interest.

2.	The sooner we understand our environment and agree on an end goal for development, the sooner we can act to improve our environment. The Colorado river was useful in this case because of its high slopes that carry water. We were able to harness the power of the flow of the river to generate electricity, irrigate farmland, prevent flooding, create jobs, and stimulate the economy. But this understanding of the environment and passing the bill to create this infrastructure was a 50-year process.

3.	Due to climate change, we must build infrastructure that is meant to control a much larger range of water conditions. Southwestern states are experiencing the longest drought in U.S. history. We must increase the range for the conditions which our water resource infrastructure must control. This is done by designing water resource infrastructure which can handle significant changes in water conditions such as flow rate and velocity.

Additional Readings
Change Name of Boulder Dam to Hoover Dam. (1947). [s.n.].

Dunar, & McBride, D. (1993). Building Hoover Dam : an oral history of the Great Depression. Maxwell Macmillan International.

Hiltzik. (2010). Colossus : Hoover Dam and the making of the American century (1st Free Press hardcover ed.). Free Press.


text:
History of video games/Platforms/Mignonette

Development
The DIY console was inspired by the Mignon game kit. The console was developed by Mitch Altman and Rolf van Widenfelt.

Launch
The Migonette was officially launched at Maker Faire 2008 which was held from May 3rd to May 4th, 2008 in San Mateo, California.

The system was sold for $34.95. The official PCB for version 1.0 lists a date of April 2008.

Like the Mignon, workshops were offered to build the console.

Legacy
The Mignonette website was last updated in 2014.

Compute
Version 1.0 of the system can use either an ATmega168 or an ATmega88.

Version 2.0 uses an ATmega168

Version 2.1 uses an ATmega328p.

Hardware
The LED dotmatrix display was capable of red and green colors. This allowed for four states per pixel, Red, Green, Yellow, or off, which was an advancement over the Mignon Game Kit, which only had red LEDs. The display had a resolution of 5 vertical LEDs by 7 horizontal LEDs.

The device has a speaker.

All versions of the device were powered by 3 AA batteries.

Revisions
2.0 and 2.1 revisions are Arduino compatible.
 * 1.0 - Latest BOM revision dated to June 5th, 2008.
 * 2.0 - Latest BOM revision dated to February 22nd, 2010.
 * 2.1 - Latest BOM revision dated to February 22nd, 2014.

2008

 * Munch - PacMan clone - preloaded on kits.
 * Attack of the Cherry Tomatoes - Side scrolling wave based action shooter game developed by Evil Mad Scientist Laboratories.
 * Attack - Developed by Evil Mad Scientist Laboratories.

Unknown Release Date

 * Tri2s - Tetris style game.
 * Marquee - Text demo software

External Resources

 * Archived official website


text:
History of video games/Platforms/Mignon

Development
The console was developed by Olaf Val of Kassel, Germany.

Launch
The website of the Mignon Game Kit suggests a launch date of 2004. However workshops were held from late 2003 to 2007. Workshops cost about 39 euros.

The Mignon Game Kit was definitely publicly available by 2005.

A Mignon Game Kit 2.0 was later launched. This console was very similar, but offered an overall improved design, as well as an upgrade to use an actual speaker, and an improved ATmega-238 micro-controller among other upgrades. Workshops for these models occurred from September 2009 to at least May 2015.

Legacy
The system was noted for fostering a connection between the user and the device.

DIY
The console was meant to be built by the end user. The build time was estimated at around 1 day for workshop participants.

Models
Three variants of the console were designed for different use cases. An "Economy" design used the least number of parts. There was also a "Basic" model with quality of life improvements such as a battery box and micro-controller socket. Finally there was a "Creativ" model with additional sensors and programming tools.

Compute
The Mignon uses an Atmel ATMEGA8-16PI microcontroller. This micro-controller included an 8-bit computer.

All models included a 9 pin D-SUB connector. "Creativ" Models included a PonyProg set.

Hardware
A LED Dotmatrix is used as display, with a resolution of 5 vertical LEDs by 6 horizontal LEDs.

A piezo speaker is used for audio.

Games & Software

 * Dot Game - The only 3rd party game listed on the official website, programmed by Jingbo Wen.
 * mignonLoop - Music Software.
 * Min Pong - Pong Clone.
 * BitShift - Surfing game.
 * Maze Diver - Ship avoidance game.

title: History of video games/Platforms/Mignon


text:
Talk:Skaneateles Conservation Area/Invasive species

Table Template

 * }

Beale's Oregon grape/leatherleaf mahonia
In the New York State Invasive Species Tiers table, Mahonia bealei and Berberis bealei are synonyms but both listed with different ranks and tiers.

— 06 September 2021

Black Swallowwort
The New York State Invasive Species Tiers table for Black Swallowwort lists the Scientific Name as Vincetoxicum louiseae, which does not appear to be a published name. It should probably be either Vincetoxicum nigrum or Cynanchum louiseae. The New York Flora Atlas currently uses Vincetoxicum nigrum and GBIF agrees. ― 01 November 2021

Chinese fountain/millet grass
Pennisetum alopecuroides and Cenchrus purpurascens appear to be synonyms but are both shown in the New York State Invasive Species Tiers table as:

However the currently accepted species name for both of these appears to be Cenchrus alopecuroides (L.) Thunb., though the New York Flora Atlas still has it as Cenchrus purpurascens Thunb. — 12 November 2021

Japanese Black Pine
Japanese Black Pine, Pinus thunbergiana accepted name by current sources is Pinus thunbergii — 12 November 2021

Leafy Spurge
According to the Euphorbia virgata page in the New York Flora Atlas: "Specimens that came in as E. esula are placed here since E. esula is currently not known from New York and in New York the name was misapplied to E. virgata."

The New York State Invasive Species Tiers table appears to be incompletely or inconsistently adjusted to reflect the change:

— 13 November 2021

Cogon grass/cogongrass
This one is surprising. The scientific names (Imperata cylindrica) are identical. Only the common names are slightly different.

— 13 November 2021

Rusty Willow
Salix atrocinerea at https://imapinvasives.natureserve.org/imap/services/page/StateSpeciesList/1267.html shows Legally Regulated = No, even though Legal Status correctly indicates Prohibited. — 14 November 2021

Beach Pea
Curious about the inclusion of Lathyrus japonicus in the New York State Invasive Species Tiers list. New York Flora Atlas lists [https://newyork.plantatlas.usf.edu/Plant.aspx?id=1493 Lathyrus japonicus Willd. var. maritimus] as native (S4), and sources in general treat the species as circumborial. — 16 November 2021


text:
Infiltrator II

Infiltrator II (known as Infiltrator on the NES) is a 1987 video game published by Mindscape and developed by Chris Gray Enterprises.

Gameplay
Infiltrator II is a game in which the player as Johnny "Jimbo Baby" McGibbits must fly a Gizmo DHX2 into enemy air space and infiltrate their ground installation.

The story and gaming strategies continue from Infiltrator published in 1986. The Mad Leader wants new ambition. The player must successfully fly to and from three enemy bases to win the game.

Flying
Any crash requires starting over the flying mission with no intermediate checkpoint, even if already at the destination.

Landing
Reaching the destination gets the flashing and wildly spinning ADF (automatic direction finder) dial.
 * 1) Zero the horizontal speed, or crash.
 * 2) Descend slowly, or crash.
 * 3) Keep the artificial horizon level by neither banking nor spinning the chopper, or crash.
 * 4) If landing in enemy base, turn on the whisper mode shortly before reaching 200 feet (60 m), or be captured by the enemy for late or omitted use of the whisper mode.

Instrument panel
The chopper has six warning lights on the top. Steady green lights are normal. Flashing red lights with audible alarm mean troubles: The ADF is much more important than the compass. The computer terminal has the correct coordinate to be entered in the communication.
 * The engine damage makes the chopper descend too fast and unstably, eventually crashing as the worst problem.
 * The battery overheats if flying too fast. Check the thermometer on the upper left. Slow down to cool to battery down, or the engine will fatally damage.
 * The oil overheats if the turbo or the whisper mode is on too long. Check the thermometer on the upper right. Turn off the turbo or the whisper mode to cool the oil down, or the engine will fatally damage.
 * The fuel running too low will fatally damage the engine, so do not excessively waste time flying. Check the fuel gauge on the right.
 * The altitude is under 200 feet (60 m). Do not be too low until landing at the destination.
 * The revolution per minute of the engine is too low.

Computer terminal
The status of six vital parts are in steady green if in good condition, or in flashing red if damaged by enemy gunfire:
 * Damaged communications computer means no sending nor receiving messages, so hurry to the destination. Nor may the ADF be set, so always set the ADF before taking off.
 * Damaged defenses mean no usage of flare nor chaff, nor may approaching missiles be detected. Hurry to the destination.
 * Damaged tactical map means no display of the chopper nor the destination. Yet properly set ADF still works.
 * Damaged turbo means no doubling the speed. The chopper cannot go faster than 450 knots (834 km/h).
 * Damaged engine will crash the chopper. Say goodbye to prepare the next try.
 * Damaged weapons may make the missiles and gun unusable.

Communication
Meeting others in the air is inevitable. Not asking first will receive other's message to "request identification". This is risky by having to guess meeting a friend or foe. Messages sent to indeed no one are replied "no transmissions received". Better quickly send a message to "request ID" when anyone may appear. When answered "(someone) requesting identification", reply with "infiltrator" to friendly flyer or "overload" if hostile flyer. Yet a few flyers always attack the player regardless of your answer, so saving yourself requires taking them down.

In enemy base
Five lives are not directly displayed. One life is lost if:
 * Captured by any enemy guard.
 * Stepping onto a landmine without using the mine detector.
 * Running out of time.
 * Going into the water.
 * In mission A, approaching the nerve gas without the neutralizer.
 * In mission B, not leaving the building fast after melting down the nuclear reactor.
 * In mission C, not using one of the ten strange cards when passing an empty room with two slots on the wall.

Inventory
For all missions: For mission B only: Vital in mission C only:
 * The sleeping gas temporarily subdues enemy guard for some seconds with smaller rage but no noise.
 * A gas grenade is noisy with larger range. Using it indoor subdues any enemy guard in the same room. Using it outdoor scares any awake enemy guard in the same screen by causing an alarm.
 * The papers are fake to hopefully pass through enemy base, but gassing any enemy guard who finds them not in order is vital to avoid an alarm.
 * The mine detector finds any landmines to avoid fatally stepping on them.
 * The missile deactivator is useful only in the rooms with missiles.
 * The coolant evaporator is useful only toward the nuclear reactor at the right time. Using it at the wrong time runs its energy out and will fail mission B once.
 * The brain scanner tells if a sitting person is the mad leader or else.
 * The brain implant converts the Mad Leader into a good person. Using it toward anyone else runs its energy out and will fail mission C once.

Buildings
An alarm control card is randomly in certain building, so the following maps cannot locate it. Avoiding the alarm is much better than wasting time finding the card.

The following maps of the buildings show coordinates with 1 to 6 from bottom to up and A to F from left to right:

Some blue or red rooms:

 * Guard: enemy guard

Green rooms:
 * WAY OUT: exit
 * LIFT1: elevator 1 in a specific building
 * LIFT2: elevator 2 in a specific building

Red rooms: In mission A: In mission B: In mission C:
 * X: locked doors
 * EROOM: electronic control room
 * SCARD: security card, required to unlock locked doors, in a red room
 * SROOM: security room with a slot to insert the security card, as a red room
 * UNIFO: hangar to change the uniform, in a red room: Properly doing so may avoid being asked by enemy guards to show the papers, unless approaching them too closely, which will render the papers useless and require gassing them. Ignore other hangars.
 * CHEMI: chemical
 * ANALY: analysis computer
 * NERVE: nerve gas
 * MISSI: missiles
 * RCARD: reactor access card
 * REACT: reactor control center
 * STRAN: ten strange cards, required to pass an empty room with two slots on the wall.
 * !!!: empty room with two slots on the wall, requiring a strange card
 * DECOY: sitting person not being the Mad Leader
 * MLEAD: Mad Leader himself

Levels
There are up to six starting levels:
 * Press '1' to begin flying mission one. (Unlocked at the beginning)
 * Press 'A' to start at enemy base one. (Unlocked at the beginning)
 * Press '2' to begin flying mission two. (Unlocked after beating enemy base one and safely landing at Home Base)
 * Press 'B' to start at enemy base two. (Unlocked after beating enemy base two and safely landing at Home Base)
 * Press '3' to begin flying mission three. (Unlocked after beating enemy base two and safely landing at Home Base)
 * Press 'C' to begin flying mission three. (Unlocked after beating enemy base three and safely landing at Home Base)

Mission 1
Set the ADF to 50.6.

Mission A

Start from the upper-left screen. Buildings in this base resembles those in enemy base 1 in Infiltrator I.

Go to the mid-left building to change the uniform (F6) if seeking to avoid the guards. B1: Exit D4: Chemical

A    B     C     D     E     F     ___________________________________ |    |     |     |     |     |UNIFO| 6  |Guard Guard Guard|Guard            | |_  _|_____|_   _|_   _|_____|_____|    |     |     |     |     |     |     | 5   |Guard Guard|      Guard|Guard      | |_  _|_   _|_   _|_____|_   _|_____|    |     |     |     |CHEMI|     |     | 4  |     |     |     |GuardXGuard      | |_  _|_____|_____|_____|_____|_   _|    |     |     |     |     |     |     | 3   |      Guard|Guard|     |Guard Guard| |_  _|_   _|_   _|_   _|_   _|_   _|    |     |     |     |     |     |     | 2   |     |Guard Guard|Guard Guard|     | |_  _|_____|_____|_____|_____|_   _|    |     |     |     |     |     |     | 1   |Guard  WAY  Guard       Guard Guard| |_____|_OUT_|_____|_____|_____|_____|

A    B     C     D     E     F

Go to the upper-right building to get the security card (A1). F1: Exit A4: Chemical

A    B     C     D     E     F     ___________________________________ |    |     |     |     |_____|     | 6   |Guard Guard Guard|Guard _____ Guard| |_____|_____|_  _|_____|_____|_   _|    |     |     |     |     |_____|     | 5   |Guard Guard       Guard _____      | |_____|_____|_  _|_____|_____|_   _|    |CHEMI|     |     |     |_____|     | 4  |GuardXGuard Guard|Guard _____      | |_____|_____|_____|_____|_____|_  _|    |     |     |     |     |_____|     | 3   |Guard       Guard|Guard _____      | |_____|_____|_  _|_____|_____|_   _|    |     |     |     |     |_____|     | 2   |      Guard       Guard _____      | |_  _|_____|_   _|_____|_____|_   _|    |SCARD|     |     |     |_____|     | 1  |     |      Guard|Guard _____  WAY | |_____|_____|_____|_____|_____|_OUT_|

A    B     C     D     E     F

Go to the lower-right building to use the security card in the security room (C4). D1: Exit F6: Uniform D6: Electronic control room E4: Nerve gas

A    B     C     D     E     F           _____________________________ |    |     |EROOM|     |UNIFO| 6        |     |     |     |     |     |          |_   _|_   _|_   _|_   _|_   _|          |     |     |     |     |     | 5         |Guard Guard Guard Guard Guard| |_____|_____|_  _|_____|_____|          |     |SROOM|     |NERVE|     | 4        |      Guard|     |     XGuard| |_  _|_____|_   _|_____|_   _|          |     |     |     |     |     | 3         |      Guard|     |Guard      | |_  _|_____|_   _|_____|_   _|          |     |     |     |     |     | 2         |      Guard|     |Guard      | |_  _|_____|_   _|_____|_   _|          |     |_____|     |_____|     | 1         |Guard _____  WAY  _____ Guard| |_____|_____|_OUT_|_____|_____|

A    B     C     D     E     F

If lucky enough in the central building in the analysis computer, getting the neutralizer may need just one chemical from the mid-lower, lower-left, mid-left, or upper-right building. Otherwise, get the second chemical to try again in the central building. Having the neutralizer allows neutralizing the nerve gas to finish the mission.

Central building C1: Exit C1-C2: Elevator C5: Neutralizer randomly in one of the analysis computer

A    B     C     D           _________________ |    |     |     | 6         |Guard Guard Guard| |_  _|_____|_   _|          |     |ANALY|     | 5        |Guard Guard Guard| |_  _|_   _|_   _|          |     |     |     | 4         |Guard|     |Guard| |_  _|_   _|_   _|          |     |     |     | 3         |     |Guard|     | |_  _|_____|_   _|          |     |LIFT1|     | 2        |Guard       Guard| |_____|_____|_____|               |LIFT1| 1              | WAY | |_OUT_|

A    B     C     D

Mid-lower building C1: Exit C1-C2: Elevator F4: Chemical

A    B     C     D     E     F     ___________________________________ |    |     |     |     |     |     | 6   |Guard Guard|      Guard|      Guard| |_  _|_____|_____|_   _|_____|_   _|    |     |     |     |     |_____|     | 5   |Guard|Guard             _____      | |_  _|_   _|_____|_   _|_____|_____|    |     |     |     |     |     |CHEMI| 4  |            Guard Guard|GuardXGuard| |_  _|_   _|_   _|_____|_   _|_____|    |     |     |     |     |     |     | 3   |Guard|Guard|Guard|                 | |_____|_  _|_____|_____|_   _|_   _|    |     |     |LIFT1|     |     |     | 2  |Guard             Guard Guard|     | |_  _|_____|_____|_____|_   _|_____|    |     |     |LIFT1|     |     |     | 1  |      Guard| WAY |      Guard Guard| |_____|_____|_OUT_|_____|_____|_____|

A    B     C     D     E     F

Lower-left building C1: Exit E6: Chemical C6: Electronic control room

A    B     C     D     E     F     _____________________________ |    |     |EROOM|     |CHEMI| 6  |           |     |GuardXGuard| |_____|_  _|_   _|_   _|_____|    |     |     |     |     |     | 5   |Guard|Guard Guard|     |Guard| |_  _|_   _|_____|_   _|_   _|    |     |     |     |     |     | 4   |     |Guard|      Guard|     | |_  _|_   _|_   _|_   _|_   _|    |     |     |     |     |     | 3   |     |Guard|Guard|Guard|     | |_  _|_   _|_____|_   _|_   _|    |     |     |     |     |     | 2   |     |Guard       Guard|     | |_  _|_   _|_   _|_   _|_   _|    |     |     |     |     |     | 1   |           | WAY |           | |_____|_____|_OUT_|_____|_____|

A    B     C     D     E     F

Mission 2
Set the ADF to 82.9.

Mission B

Start from the lower-right screen. Use the mine detector whenever there is any doubt, especially in the forest. Stay away from the lonely guard in the forest with landmines in the mid-upper screen.

Go to the mid-left building to change the uniform (F6). Get the security card (D5). D1: Exit D1-D2: Elevator

A    B     C     D     E     F                 _______________________ |    |     |     |UNIFO| 6              |Guard       Guard|     | _____|_  _|_   _|_   _|_   _|          |     |     |SCARD|     |     | 5        |      Guard|     |      Guard| |_  _|_____|_____|_____|_   _|          |     |     |     |     |     | 4         |     |Guard       Guard|     | |_  _|_   _|_   _|_   _|_   _|          |     |     |     |     |     | 3         |Guard      |     |      Guard| |_  _|_____|_____|_____|_   _|          |     |     |LIFT1|     |     | 2        |                             |          |_____|_____|_____|_____|_____|                      |LIFT1| 1                    | WAY | |_OUT_|

A    B     C     D     E     F

Go to the upper-left building to get the reactor access card (B4). F1: Exit A2: Elevator

A    B     C     D     E     F     ___________________________________ |    |     |     |     |     |     | 6   |Guard Guard                   Guard| |_  _|_   _|_   _|_   _|_____|_   _|    |     |     |     |     |     |     | 5   |     |Guard|     |     |           | |_  _|_____|_   _|_   _|_____|_   _|    |     |RCARD|     |     |     |     | 4  |Guard      |     |     |Guard      | |_  _|_   _|_   _|_   _|_   _|_   _|    |     |     |     |     |     |     | 3   |                       |Guard      | |_____|_____|_____|_____|_____|_  _|    |LIFT1|     |     |     |     |     | 2  |     |Guard|     |Guard|     |Guard| |_  _|_   _|_   _|_   _|_   _|_   _|    |     |     |     |     |     |     | 1   |     |                         WAY | |_____|_____|_____|_____|_____|_OUT_|

Other A     B     C     D     E     F     _____ |LIFT1| 2  |     |    |_   _|___________    |     |     |     | 1   |                 |    |_____|_____|_____|

A    B     C

Go to the upper-right building to use the security card in the security room (B2, non-ground level). Then deactivate the missiles (B3, D1, E3, non-ground level). E1: Exit A5, E5: Elevators B5, ground level: electronic control room

Ground A    B     C     D     E     _____________________________ |LIFT1|EROOM|    |     |LIFT2| 5  |     |     |Guard            | |_  _|_   _|_   _|_   _|_____|    |     |     |     |     |     | 4   |      Guard|Guard|Guard Guard| |_  _|_____|_   _|_____|_____|    |     |     |     |     |     | 3   |Guard                   Guard| |_____|_____|_  _|_____|_   _|    |     |     |     |     |     | 2   |Guard Guard|Guard|      Guard| |_  _|_   _|_   _|_   _|_   _|    |     |     |     |     |     | 1   |Guard       Guard|Guard| WAY | |_____|_____|_____|_____|_OUT_|

Other A     B     C     D     E     F     ___________________________________ |    |     |     |     |     |     | 6   |            Guard|                 | |_____|_  _|_   _|_   _|_____|_   _|    |LIFT1|     |     |     |LIFT2|     | 5  |           |Guard|                 | |_  _|_____|_____|_____|_   _|_____|    |     |     |     |     |     |     | 4   |Guard             Guard Guard      | |_  _|_____|_   _|_   _|_____|_   _|    |     |MISSI|     |     |MISSI|     | 3  |     |     XGuard|     |     XGuard| |_  _|_____|_____|_   _|_____|_   _|    |     |SROOM|     |     |     |     | 2  |     |Guard      |Guard|Guard      | |_  _|_____|_   _|_____|_   _|_____|    |     |     |     |MISSI|     |     | 1  |                 |     XGuard Guard| |_____|_____|_____|_____|_____|_____|

A    B     C     D     E     F

Go to the lower-left building. Deactivate the missiles (B2, non-ground level). Melt down the nuclear reactor (C4, non-ground level) in its with the coolant evaporator only at the right time. Then hurry out of the building before being killed by the overheat! C1: Exit C6, D6: Elevators D1, ground level: security room

Ground A    B     C     D     E     F     ___________________________________ |    |     |LIFT1|LIFT2|     |     | 6  |                              Guard| |_  _|_____|_____|_____|_____|_   _|    |     |                       |     | 5   |Guard|                       |Guard| |_  _|_____             _____|_   _|    |     |     |           |     |     | 4   |           |           |Guard      | |_____|_  _|           |_   _|_____|    |     |     |           |     |     | 3   |           |           |      Guard| |_  _|_____|           |_____|_   _|    |     |                       |     | 2   |     |                       |Guard| |_  _|_____|_____|___________|_   _|    |     |     |     |SROOM|     |     | 1  |             WAY |Guard            | |_____|_____|_OUT_|_____|_____|_____|

Other A     B     C     D     E     F     ___________________________________ |    |     |LIFT1|LIFT2|     |     | 6  |Guard Guard      |            Guard| |_  _|_____|_____|_____|_____|_   _|    |     |     |     |     |     |     | 5   |           |Guard       Guard      | |_  _|_____|_____|_____|_____|_   _|    |     |     |REACT|     |     |     | 4  |Guard|     |GuardXGuard            | |_  _|_   _|_____|_____|_____|_   _|    |     |     |     |     |     |     | 3   |           |Guard       Guard      | |_  _|_____|_____|_____|_____|_   _|    |     |MISSI|     |     |     |     | 2  |     |     XGuard|Guard            | |_  _|_____|_   _|_____|_____|_   _|    |     |     |     |     |     |     | 1   |Guard Guard            |      Guard| |_____|_____|_____|_____|_____|_____|

A    B     C     D     E     F

Mission 3
Set the ADF to 10.2.

Mission C

Start from the upper-right screen.

Go to the lower-left building to change the uniform (B6, ground level) if seeking to avoid the guards. Get ten strange cards (F5, non-ground level) that are vital to pass some empty rooms with two slots. C1: Exit D6: Elevator B5, non-ground level: sitting person, not the Mad Leader

Ground A    B     C     D     E     F     ___________________________________ |    |UNIFO|     |LIFT1|     |     | 6  |           |Guard|      Guard|     | |_  _|_____|_   _|_____|_   _|_   _|    |     |     |     |     |     |     | 5   |Guard      |Guard|     |Guard|Guard| |_  _|_   _|_   _|_   _|_   _|_   _|    |     |     |     |     |     |     | 4   |     |Guard Guard|Guard|Guard Guard| |_____|_  _|_   _|_   _|_   _|_   _|    |     |     |     |     |     |     | 3   |Guard Guard            |     |Guard| |_  _|_   _|_____|_   _|_____|_   _|    |     |     |     |     |     |     | 2   |Guard       Guard Guard Guard      | |_____|_  _|_   _|_____|_   _|_   _|    |     |     |     |     |     |     | 1   |           | WAY |           |Guard| |_____|_____|_OUT_|_____|_____|_____|

Other A     B     C     D     E     F     ___________________________________ |    |     |     |LIFT1|     |     | 6  |       !!!                    Guard| |_  _|_____|_   _|_____|_   _|_   _|    |     |DECOY|     |     |     |STRAN| 5  |Guard|     |       !!! |   |_   _|__x__|_____|_____|_   _|_   _| |    |     |     |     |     |     | 4   |Guard Guard       Guard|           | |_____|_____|_____|_____|_____|_____|

A    B     C     D     E     F

Go to the mid-left building and get the security card (F1). B1: Exit

A    B     C     D     E     F     ___________________________________ |    |     |     |     |     |     | 3   |Guard       Guard Guard Guard      | |_  _|_____|_____|_____|_____|_   _|    |     |     |     |     |     |     | 2   |Guard       Guard|           |Guard| |_  _|_____|_____|_   _|_   _|_   _|    |     |     |     |     |     |SCARD| 1  |Guard  WAY   !!! |    |    |_____|_OUT_|_____|_____|_____|_____|

A    B     C     D     E     F

Go to the lower-right building to use the security card in the security room (B6, E6, ground level). E1: Exit D2: Elevator B5, non-ground level: sitting person, not Mad Leader

Ground A    B     C     D     E     F     ___________________________________ |    |SROOM|     |     |SROOM|     | 6  |      Guard|Guard|Guard|Guard Guard| |_  _|_____|_   _|_   _|_____|_   _|    |     |     |     |     |     |     | 5   |      Guard Guard|Guard|Guard      | |_____|_  _|_   _|_   _|_   _|_____|    |     |     |     |     |     |     | 4   |Guard Guard       Guard       Guard| |_  _|_____|_____|_   _|_____|_   _|    |     |     |     |     |     |     | 3   |      Guard       Guard Guard      | |_  _|_   _|_____|_____|_   _|_   _|    |     |     |     |LIFT1|     |     | 2  |     |       !!!       |Guard Guard| |_  _|_____|_____|_____|_   _|_   _|    |     |     |     |     |     |     | 1   | WAY |Guard             Guard|     | |_OUT_|_____|_____|_____|_____|_____|

Other A     B     C     D     E     F           _____ |DECOY| 5        |     |          |_ X _| |    | 4          Guard| |_  _|          |     | 3         |Guard| |_  _|_________________          |     |     |LIFT1|     | 2        |                       |          |_____|_____|_____|_____|

B    C     D     E

The mid-lower building has a brain wave readout (E6). C1: Exit F5: Electronic control room

Ground A    B     C     D     E     F     ___________________________________ |    |     |     |     |BRAIN|     | 6  |       !!!  Guard|GuardXGuardX     | |_  _|_____|_   _|_   _|_____|_____|    |     |     |     |     |     |EROOM| 5  |Guard|     |Guard|Guard Guard|     | |_  _|     |_   _|_____|_   _|_   _|    |     |     |     |     |     |     | 4   |Guard|     |Guard Guard Guard|     | |_  _|     |_   _|_   _|_____|_   _|    |     |     |     |     |     |     | 3   |Guard|     |      Guard Guard      | |_  _|     |_____|_____|_   _|_   _|    |     |                       |     | 2   |Guard|                       |     | |_  _|_____ _____ _____ _____|_   _|    |     |     |     |     |     |     | 1   |      Guard  WAY  Guard  !!! |   |_____|_____|_OUT_|_____|_____|_____|

Other A     B     C     D     E     F

Go to the upper-left building to use the brain scanner and the brain implant to convert the Mad Leader (E2, ground level) into a good person. This building has six elevators, but hang on as the victory is near. Finishing this mission and successfully flying back wins this game. B1: Exit A3, B3, C3, A6, B6, C6: Elevators

Ground A    B     C     D     E     ___________________________________ |LIFT4|LIFT5|LIFT6|    |     |     | 6  |     |     |             !!!       |    |_   _|_   _|_____|_____|_____|_   _|    |     |     |     |     |     |     | 5   |Guard|             !!! Guard|Guard| |_  _|_____|_   _|_____|_   _|_   _|    |     |     |     |     |     |     | 4   |      Guard  !!! Guard|    |Guard| |_____|_____|_____|_  _|_   _|_   _|    |LIFT1|LIFT2|LIFT3|     |     |     | 3  |     |     |     |Guard Guard|Guard| |_  _|_   _|_   _|_   _|_____|_   _|    |     |     |     |     |MLEAD|     | 2  |Guard       Guard|Guard|     |Guard| |_  _|_   _|_   _|_   _|__X__|_   _| |    |     |     |     |     |     | 1   |       WAY       |     |Guard      | |_____|_OUT_|_____|_____|_____|_____|

Other A     B     C     D     E     F     ___________________________________ |LIFT4|LIFT5|LIFT6|    |     |     | 6  |     |     |      Guard Guard      | |_  _|_   _|_____|_   _|_____|_   _|    |     |     |     |     |     |     | 5   |Guard|Guard       Guard      |Guard| |_  _|_____|_   _|_____|_   _|_   _|    |     |     |     |     |     |     | 4   |            Guard      |Guard Guard| |_____|_____|_____|_  _|_   _|_   _|    |LIFT1|LIFT2|LIFT3|     |     |     | 3  |     |     |      Guard|Guard Guard| |_  _|_   _|_____|_____|_   _|_   _|    |     |     |     |     |     |     | 2   |Guard|      Guard       Guard|     | |_  _|_____|_____|_   _|_____|_   _|    |     |     |     |     |     |     | 1   |      Guard                   Guard| |_____|_____|_____|_____|_____|_____|

A    B     C     D     E     F

title: Infiltrator II


text:
Signetics 2650 & 2636 programming/Console Hardware

Externally these consoles are very similar to one another apart from their styling. They all have a slot for the game cartridge, four switches on the front, a pair of hand-controllers, and leads for power input and connection to a TV. Some have external power packs that supply low voltages to the console from the mains, while others perform this function internally.

The four switches on the console are power on/off, reset/load, start and select. (The load label that appears on some machines has led to some misinformation appearing on the web, as it has given the impression that the game is loaded from the cartridge to internal memory. This is incorrect as there is no internal memory on these machines. That button simply forces the microprocessor to start executing the program at memory address $0000 in the cartridge.)

Some of the consoles, such as the Database, have all the electronics on one printed circuit board, while others such as the Interton have divided the circuit into modules housed on smaller boards.

The game cartridge was configured in several different formats. Most had either a 2k or a 4k ROM, while some were 6k ROM and some had 1k RAM. The Acetronic Hobby Module was 2k ROM and 2k RAM.

System architecture
This block diagram shows the main components of the console and their most significant interconnections:

Clock generation
All the necessary clocks for the system are derived from a single 8.867238 MHz crystal connected to the the video encoder. The encoder uses this for generating colour signals in its composite video output. It also divides it by 2½ to give a 3.55 MHz clock for the 2621 sync generator.

The sync generator passes this to the 2636 PVI as a pixel (or position) clock, and divides it by four to clock the microprocessor at 887 kHz. It also generates the vertical and horizontal reset signals for the PVI, as well as composite video timing signals for the video encoder.

Processor
The Signetics 2650 is an eight bit microprocessor capable of addressing 32kB of memory. However, in this console only 13 of its address lines are used to access up to 8kB of memory.

The Reset signal causes it to start executing code at address $0000.

An $\overline{Interrupt}$ signal from the PVI, in conjunction with a vector supplied by the PVI, can cause execution to temporarily switch to $0003.

The Sense input is used to detect the state of the VRST signal (vertical blanking). The Flag output is used to determine which of the joystick potentiometers are connected to the PVI.

2636 PVI
The 2636 Programmable Video Interface has 108 registers that control its audio and video output. Four other registers provide the processor with information about video object collisions and analogue joystick data. A further 37 registers are available as general purpose memory locations.

The PVI also generates chip select signals for various interface circuits and memory in the games cartridge. It also sends and interrupt request signal to the processor when it needs attention. See 2636 PVI for more details.

Effects
The PVI can only generate a single square wave frequency. This is fed to some audio effects circuits that are controlled from the microprocessor via the 74LS378 latches. These circuits:
 * turn the PVI audio on/off
 * turn on white noise
 * cause an explosion sound
 * set one of four volume levels

One other bit in the effects register can invert the colour of the background grid and screen.

Player inputs
The Reset button on the console causes the processor to start executing the program at memory address $0000 in the game cartridge.

The Start, Select and keypad buttons are all controlled by the 74LS258 and 74LS156. They are arranged as a matrix, with the '156 selecting the column, and the '258 reading the data from the rows.

Each joystick controls two variable resistors. The four variable resistors are connected to the two analogue-to-digital converter inputs on the PVI via the CD4053 analogue multiplexer. The Flag output from the microprocessor controls which two resistors are to be measured.

Programmers should note that the joysticks are self-centring on some consoles and not on others. This can have a big impact on how they are used and programmed.


text: File:Infiltrator II Base A.jpg

title: File:Infiltrator II Base A.jpg


text:
User:Crest.boy

Bruce Wen (https://wenijinew.medium.com)

Developer, working at Ericsson AB.

Interested area: Automation testing, Machine Learning.

Good at: Java, Bash, Python.

Enjoy life and writing.

title: User:Crest.boy


text: Market Influences on Clinical Trials/Printable version


text: AutoCAD/Printable version

title: AutoCAD/Printable version


text:
Wikijunior talk:The Little Gardener

Potentially misleading/problematic title considering the book's target age group
Many 10- to 12-year-olds are not that much smaller than adults and/or do not consider themselves little, and they may even feel insulted by being called little. If they see a book called The Little Gardener, there's a good chance that they may think that it's a book for little kids and not even click on it. If they do click on it and see that it's for their own age, they might still not read it, thinking that it's written by adults who are so out of touch with tweens that they consider them to be small children.

In my opinion, renaming this book to The Young Gardener or something similar would still achieve the same purpose without potentially insulting or luring away the book's target audience. Evil Sith Lord (discuss • contribs) 06:58, 14 November 2021 (UTC)

title: Wikijunior talk:The Little Gardener


text:
Public-Private Partnership Policy Casebook/Sepulveda Transit Corridor

This case study reviews the Sepulveda Transit Corridor project as the collaborative work of Wossen Bekalu, Taylor Lucas, and Katie Thompson. The casebook is a George Mason University graduate program product as an assignment for the Public-Private Partnership Policy course. This course was taught under the leadership of Dr. Jonathan Gifford. The views expressed here are the product of student research. It does not represent the views of Dr. Jonathan Gifford or George Mason University.

The casebook explores key actors, event timelines, risks, financial structures, policy issues, and key takeaways.

Summary
Metro's Sepulveda Transit Corridor Project is part of a plan to make it easier to get around. It hopes to create better transit between the San Fernando Valley, the Westside, and Los Angeles International Airport (LAX). This high-capacity rail line will help take cars off the road and provide more travel options.

The natural barrier created by the Santa Monica Mountains makes the I-405 one of the busiest freeways in the nation. Metro recognizes that more than one solution will be needed to help reduce congestion. To address this, they are also pursuing the I-405 Multimodal Corridor Plan and I-405 Sepulveda Pass ExpressLanes in this area.

The first phase of this project is connecting the San Fernando Valley and Westside. The second phase is connecting the Westside and LAX. Without additional funding for this project, Phase 1 is slated to be completed and open for service between 2033-2035. Phase 2 is expected to be completed open for service between 2057-59.

Metro seeks to accelerate this timeline by using P3s with a projected completion date of 2028 in time for the Olympics. However, a more realistic timetable is 2033, even with the use of a private partner.

The focus of this case study will be Phase 1, the San Fernando Valley and Westside.

Annotated List of Actors
There are over 12,000 stakeholders that indicated their interest or concern regarding the implementation of the proposed Sepulveda Transit Corridor Project. Figures such as this indicate that there is high public interest. The following is a partial list that includes the primary stakeholders as well as some of the major stakeholders. The selection of the major stakeholders listed below is limited to those that have a more significant impact or say in how the project will be executed.

Primary Public Stakeholders
Los Angeles County Metropolitan Transportation Authority (Metro) is the agency that plans, operates, and coordinates funding for most of the transportation system in Los Angeles County. Metro has also coordinated, designed, built, and operated LA county's Transit system servicing more than 10 million people in the 1,433-square-mile service area.

California Department of Transportation or Caltrans manages the state's highway system. The Sepulveda Transit Corridor Project was proposed as a measure to reduce congestion on the I-405. Caltrans will have requirements and concerns regarding the construction for the Valley-Westside segment of the project. This is because the Valley-Westside segment alternatives cross over or under US 101 with one alternative running in or near Caltrans right-of-way along the west side of I-405 in the Sepulveda Pass. Since 2018, Caltrans has also been examining operational improvements and ExpressLanes in the I-405 corridor. Metro and Caltrans agreed that further coordination might be needed after the I-405 ExpressLanes project has begun.

Primary Private Stakeholders
BYD LA SkyRail Express is a proposal created by BYD Co. Ltd. ("Build Your Dreams"). BYD is a Chinese manufacturing company headquartered in Shenzhen, Guangdong, China, that entered the global rail transit market with a monorail system in 2016. BYD has chosen to partner with 33 Disadvantaged Business Enterprise as it performs pre-development work on this Project. This team includes John Laing, Skanska, Gensler, HDR, ACI, and Innova.

Sepulveda Transit Corridor Partners(STCP) - Bechtel is a proposal led by Bechtel Industries with Bechtel Development Company, Meridiam Sepulveda, and American Triple I (ATI) as equity partners in this venture. Bechtel will act as the Lead Construction Contractor and Lead Engineering Firm for this proposal because it is a globally trusted engineering, construction, and project management firm. Additionally, STCP will have the engineering expertise of Mott Macdonald, T.Y. Lin, and Systra with the infrastructure development experience of Meridiam. ATI and Meridiam also have a successful track record of developing, managing, and investing in complicated public-private partnerships.

Narrative of the Case
Commuter transport and congestion is a significant problem in the Sepulveda Pass. In 2012 LA’s Metro team initiated plans to improve the situation via the Sepulveda Pass Systems Planning Study. More than one solution will be needed to help reduce congestion, so they are also pursuing the I-405 Multimodal Corridor Plan and I-405 Sepulveda Pass ExpressLanes in this area. With the passage of the transportation sales tax in 2016, Metro identified $9.5 billion in government funding to connect the San Fernando Valley to LAX. The subject of this report is the first phase of the project. The first phase is intended to connect the San Fernando Valley to the Westside. In order to design this phase, Metro entered into a PDA with LA SkyRail Express and Sepulveda Transit Partners-Bechtel.LA SkyRail Express will propose a Monorail solution, and Sepulveda Transit Partners-Bechtel will propose a Heavy Rail transit solution. Their goal is to have the first section open for service between 2033 and 2035 and hope to have Phase 2 open for service between 2057 and 59.

The LA SkyRail plan would cost roughly $6.1 billion, with an estimated $221 million coming from outside investment and an annual operating cost of $63 million thanks to budget cuts from unattended train operating systems. Bechtel’s proposal would cost around $10.8 billion, with $634 million coming from outside investment. The operating cost would be close to $118 million annually. More financing information will become available with the progression of the project.

Government officials and community leaders have a number of policy questions regarding the project. These questions will begin to have answers once the ERI is published. Metro will have to address any wildlife and natural world impact, including pollutant concerns and earthquake safety. Initial projections believe that pollution will decrease with the completion of the project as cars will be taken off the road when those computers switch to the new rail system. The new rail system is also projected to be more energy efficient. Metro will also need to account for: how they plan to serve minority communities who have greater need of public transit; how long and where construction will go on; and the particulars of the financing situation. The Monorail system has tremendous community pushback because it is above ground, resulting in more noise, more land needed, and unsightly structures in their neighborhoods. The heavy rail option is expected to have a significant portion underground to avoid these issues.

Timeline of Events
The following is the proposed timeline for executing the Sepulveda Transit Corridor Project if Metro decides to go with the P3 model.

Maps of Locations
Click here to view the map of the Sepulveda Transit Corridor Project.

The above map shows the proposed routes of the Sepulveda Transit Corridor Project. The route is unconfirmed and still needs to undergo several rounds of evaluation before the final refinement of project plans and construction.

It is expected that the line would begin at the Van Nuys Metrolink Station, where it would connect with the future East Fernando Valley Light Rail. It is expected to end with a connection at the E Line. This line would include stops at future G & D line connections along the way.

Risk Matrix
Currently, a risk matrix does not exist as there is no P3 contract in place.

The following is a hypothetical risk matrix derived from existing documents and information released to the public by Metro.

Contract Type
In March of 2021, The Los Angeles County Metropolitan Transportation Authority awarded PDA contracts to LA SkyRail Express and Sepulveda Transit Partners-Bechtel.

The PDA will analyze the geography and existing build environment along the Sepulveda Pass to identify potential project design and construction challenges. It will also facilitate more possible innovations while accelerating the scheduled development and construction portion of the project.

The ultimate goal of the PDA is to increase the affordability of the proposed transit solutions. This will ensure that the project is cost-effective in the design and build phase and in the operate and maintain phase.

The LA SkyRail Express PDA contract for the proposed Monorail transit solution was awarded in the amount of $63,605,132.

The Sepulveda Transit Corridor Partners Bechtel PDA contract for the proposed Heavy Rail transit solution was awarded in the amount of $69,882,427.

Cost
The two competing contract bidding teams, LA SkyRail Express and Sepulveda Transit Corridor Partners (led by construction and engineering giant Bechtel Corp. of Reston, VA), have each submitted a bid for this project. LA SkyRail Express submitted a bid for a $6.1 billion aerial monorail. In comparison, the Sepulveda Transit Corridor Partners submitted a bid for a $10.8 billion combination of heavy tunnel and aerial rail.

The LA SkyRail Express' $6.1 billion cost includes an estimated $221 million in outside equity investment. Once construction is complete, the proposal will give an annual operating cost estimate of $63 million. One cost saver is the plan for unattended train operations. The LA SkyRail Express bid scored highest on Metro's bid evaluation, mainly in the area of diversity and inclusion.

The Betchel led bid chose a single-bore tunnel design to keep the cost as low as possible. The total $10.8 billion project cost includes $634 million in anticipated outside equity investment. Once construction is complete, annual operating expenses are expected to be around $118 million, which is nearly twice the LA SkyRail Express proposal.

According to the most recent community update meeting held on October 28, 2021, this project will be very competitive. They do not currently know what they will do if they do not get federal or state funding. However, they are hopeful of receiving it.

* Currently proposed stations are only designed for 6 train cars, proposals do not include price for later additions to increase capacity.

Financial Structure
Currently, a financial structure for the Sepulveda Transit Corridor Project does not exist as there is no P3 contract in place. The tables below illustrate the financial breakdown of the PDA Contract awarded to BYD and SCTP- Bechtel as well as the possible funding sources of the Project when it nears execution. The following are possible funding sources that would facilitate the expedition of the project's completion as derived from existing documents and information released by Metro.

Institutional Structure
As previously stated, there is no P3 contract in place, so the framework below describes the organizational structure of the Sepulveda Transit Corridor Project.

BYD and SCTP- Bechtel as the awardees of the PDA contract report to Program Management Consultants Working under the PDA Project Manager, Kavita Mehta.

The Environmental Consultant Team reports to the Environmental Project Manager, Peter Carter.

Kavita Mehta works hand-in-hand with Colin Peppard from the Office of Extraordinary Innovation, Carolina Coppolo from Vendor/Contract Management, and Peter Carter. He works with Karen Swift, the Communications Lead.

Kavita Mehta answers to Rick Meade, the PDA Director.

Peter Carter reports to Deputy Executive Officer of Mobility Corridors, Cory Zelmer. He reports to the Project Director, David Mieger.

Rick Meade works in conjunction with the County Counsel and David Mieger.

Rick Meade & David Mieger report to the Executive Leadership Board that contains: Phil Washington, Rick Clarke, Jim de la Loza, and Joshua Schank.

Debra Avila and Yvette Rapose serve as SLT Advisors to the Executive Leadership and are outside the above chain of command.

Clear Identification of Policy Issues
There are some key policy issues of concern to community leaders regarding the Sepulveda project:

 * 1) The Environmental Impact Report (ERI), scheduled to be released on November 30, 2021, will contain numbers regarding wildlife impact, pollution, and earthquake readiness.
 * 2) Community activists want to ensure that the line is servicing at-risk communities. Minority communities need greater access to public transit in order to have greater opportunities. Any option that enters development must consider how to serve those communities best. This aspect could be key as some nonprofit organizations have expressed interest in assisting with the project's financing as long as the neighborhoods they must care about are well serviced.
 * 3) There is a general question of how the passage of the infrastructure bill would impact this project. In short, funding is not expected to be impacted. However, more details are expected to become public with the publication of the ERI.
 * 4) Many community leaders and homeowners are worried about the length of time construction will go on and what land will be needed to build the rail system. Again, more information will become public with the publication of the ERI.

Takeaways and Points of Discussion
The planning and procurement process involves a great number of actors. At every phase of the process, the number of people who need to be consulted or give unsolicited opinions is astounding. This shows Metro’s commitment to finding the best solution to the transit problems the communities face as well as ensuring the public has the information they need. With that in mind, there is not a great deal of clarity or forthrightness in this phase of a project because everything is in a very larval stage. That being said, here are a number of questions to consider.

 * 1) What project should be chosen given current information?
 * 2) Is the cost-consideration more or less important than community reaction?
 * 3) Are there other steps that need to be taken to ensure a successful project?

Additional Readings
Los Angeles County Transportation Expenditure Plan, November 2016 (1pg, Line Items 15 & 16 for Phase 1; Line Items 22 & 23 for Phase 2)

Feasibility Report, November 2019(184pg)

Sepulveda Transit Corridor Project Frequently Asked Questions, November 2021(8pg)