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Balance of Systems
Published in Majid Jamil, M. Rizwan, D. P. Kothari, Grid Integration of Solar Photovoltaic Systems, 2017
Majid Jamil, M. Rizwan, D. P. Kothari
An electrical junction box is a container for electrical connections. They are usually intended to conceal them from sight and deter tampering. A small metal or plastic junction box may form part of an electrical conduit or thermoplastic-sheathed cable wiring system in a building. If designed for surface mounting, it is used mostly in ceilings, under floors, or concealed behind an access panel—particularly in domestic or commercial buildings. An appropriate type may be buried in the plaster of a wall or cast into concrete with only the cover visible. It sometimes includes built-in terminals for the joining of wires. A similar, usually wall-mounted, container called a pattress accommodates switches, circuits, and the associated connecting wiring. The term junction box may also be used for larger items, such as piece of street furniture.
Development of a new distributed optical fibre sensor as borehole extensometer
Published in Noor Amila Wan Abdullah Zawawi, Engineering Challenges for Sustainable Future, 2016
The second method of utilizing a corrugated plastic tube (or flexible electrical conduit) is an attractive option because the ribbed surface of plastic tube has more contact surface and therefore potentially providing better adhesion between the grout and plastic tube and the fibre attached onto the tube. Moreover, the materials used for this technique are very cheap. For this study, an eight-ribbon Fujikura cable is attached externally and internally inside the plastic tube (Mohamad et al., 2009). As shown in Figure 3b, the fibre fixed externally on the tube is pre-tensioned and spot-glued whereas the inner fibre inside the tube is loosely laid inside. A special type of glue (melted glue sticks) that is flexible when cured (so that it follows the movement shape of the tube) is used.
Conflict Paradox: Encouraging Debate without Letting It Become Destructive
Published in Gary Santorella, Lean Culture for the Construction Industry, 2017
So, what is the moral of this story? What you want for your project is the best ideas to emerge, not little pieces of okay ones that together, don’t add up to a good one. Compromises will rarely take you where you need to go. At some point you will have to make a decision between two competing options. You can’t simultaneously run electrical conduit below ground and in raceways. It has to be one way or the other. As Roger Martin states in his book The Responsibility Virus (p. 117), “A well-framed choice is an irreversible commitment.” So how do you effectively make these kinds of choices, particularly when the team doesn’t agree? You’ll see that in many ways, Martin’s framework is similar to a single issue Kaizen event. For example:
Hypolimnetic oxygenation 2: oxygen dynamics in a large reservoir with submerged down-flow contact oxygenation (Speece cone)
Published in Lake and Reservoir Management, 2019
Alex J. Horne, Rodney Jung, Hubert Lai, Bill Faisst, Marc Beutel
The rest of the system consisted of a 127 kW, 0.9 m3/s (170 hp, 35 cfs) Flygt submersible water pump, a 50 m3 (13,000 gals) onshore liquid oxygenation tank and its large evaporator (Fig. 2b), and a 400 m underwater oxygen pipeline and electrical conduit. A 45 m long diffuser manifold was installed on legs 4.5 m above the reservoir bed to release oxygenated water horizontally up-reservoir via 90 orifices, each of 5 cm diameter (Fig. 1). Originally the manifold was to be only 2 m off the sediments but it was elevated further to give a safety factor for sediment disturbance. The jets dilute the initial high oxygen concentrations to a level safe for fish. When Camanche Reservoir is at its lower operating water elevation, the water depth near the dam is 23 m. At this depth, the cone releases water with a DO of 80 mg/L (Speece, 1992). Fish breathing dissolved gas at high pressure at one depth can be harmed if they rapidly reach a shallower depth, where the lower pressure cause the gas to come of out solution in bubbles in the blood and causes the fish swim bladders to expand, with lethal consequences (Abernethy et al. 2001). The best examples are the nitrogen gas “bends” that killed fish below dams prior to modern redesign (Weitkamp and Katz 1980). Oxygen supersaturation can also produce similar fish deaths, so the diffuser was designed to entrain enough surrounding water for a minimum dilution of 10:1 to meet the ambient target of 8 mg/L (Speece 1992). This is below the saturation level at bottom water temperatures (13–15 C), so even if the fish swim rapidly to the surface their swim bladders will not be affected.