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Duplex Circular Wet Well (DCWW) lifting pump stations are utilized for pumping clear and solid-bearing liquid. Understanding the effect of design criteria on pump performance is important to minimize maintenance costs and maximize efficiency. There are currently no known full-scale laboratory studies that have been performed to investigate the overall design of DCWWs. The objective of the research was to evaluate the impact of various design criteria, such as internal geometry and operating conditions on the performance of DCWW pump stations and provide documentation and recommendations which will be used to augment the current Hydraulic Institute/American National Standard for Pump Intake Design (ANSI/HI 9.8-1998), (HI) guidelines. The research was conducted in two phases; Phase 1 consisted of performing a comparative analysis of the basic flow patterns within the wet well by means of Computational Fluid Dynamics (CFD), Phase 2 consisted of performing detailed evaluations of various design aspects on pump performance using a full-scale Physical Model constructed for the research. The CFD research provided indications regarding potential performance problems that may occur due to poor flow patterns and potential pump suction swirl, while the physical research provided a basis for determining the relative advantages of different designs. The physical research included the evaluation of general flow patterns, free-surface and subsurface vortices, air entrainment and pump suction swirl. Measurement of the steady state swirl within the pump showed unacceptable performance in accordance with the HI acceptance criteria. Swirl data collected under real-world dynamic operating conditions showed that the pump typically did not experience the adverse conditions indicated at steady state. Normal (symmetrical) pump orientation resulted in more favorable operation in terms of pump swirl and ingestion of entrained air than a coplanar (inline) condition. A minimum water elevation was established to minimize air-entrainment and swirl entering the pumps, reducing possible effects such as cavitation and vibration of the pump impeller. Air-core subsurface vortices were present under the pumps, requiring pump-cones to be installed. The collection of real-time dynamic data will allow design engineers to better understand actual pump performance under normal cycling and clean-out modes, reducing the operating time under unfavorable conditions and overall maintenance requirements.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Commercial off-the-shelf (COTS) graphics processing units (GPU) perform the signal processing operations needed for video games and similar consumer applications. The high volume and competitive nature of that industry have produced inexpensive GPUs with impressive amounts of signal processing power. These devices use parallel processing architectures to execute DSP algorithms far faster than single, or even multi-core central processing units typically found in workstations. This paper describes a project which improves the performance of a radar telemetry application using the NVidia™ brand GPU and CUDA™ software, although the results could be extended to other devices.

The development of station design provided new dimensions to both the sense and sensation of space. This is to be recaptured in the design of the museum, which requires obtaining an understanding of the influence, implications and impact railway stations and their supporting infrastructure had on architecture, the cityscape and the urban fabric, due to their large size, area and enclosed volume. Station design has contributed to modern design through the need to satisfy the uninterrupted, free-space enclosure of large volumes, necessitating progress in the knowledge of the structural application of the new materials discovered during the Industrial Revolution from which the modern architect is still benefiting. The impact of stations in these three mentioned fields furthermore had an indirect impact on society. The determination of all these influences by stations and their design will form the research subject of this dissertation. / Dissertation (MArch(Prof))--University of Pretoria, 2008. / Architecture / unrestricted

The goal of this project is to implement and verify an optimization model for finding a min-cost selection of switches and train paths at railway stations. The selected train paths must satisfy traffic requirements that commonly apply to regular railway traffic. The requirements include different combinations of simultaneous and overtaking train movements. The model does not rely on timetables but does instead utilize different path sets that are produced via algorithms based on a network representation of the station layout. The model has been verified on a small test station and also on the real station layout at Katrineholm. These tests show that the model can solve the problem for mid size stations with through traffic. In addition, we have performed a literature study regarding maintenance problems for switches and crossings. We have also looked at articles regarding the scheduling and routing of trains through railway stations. Finally we present some possible ways to further improve the model for more realistic experiments.

Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The Superconducting Quantum Interference Device (SQUID) is one of the most sensitive magnetic field sensors in the world. These instruments can only be used optimally for geomagnetic research if placed far from man-made magnetic signals. Moving the SQUID to a remote site leads to several infrastructure-related problems including construction, power, data connectivity, and cryogenic cooling. This thesis investigates possible solutions to these problems and develops guidelines for designing future remote SQUID stations. A remote SQUID observatory typically consists of three structures placed approximately 40 m apart. These include: the control room, which houses all computers and supporting electronics, the power hut, which contains a regulated battery bank charged from a solar array that delivers DC power to the rest of the system, and the SQUID hut itself, which is thermally insulated by cavity walls. The SQUID is placed on an isolation pillar that decouples it from structural vibrations due to wind and outside temperature uctuations. The temperature inside the SQUID hut is also monitored as changes in temperature can result in small deformations of the SQUID mounting system which lead to changes in the SQUID's orientation. The changes in the orientation will appear as slow varying magnetic signals on the SQUID output. In principle, it is possible to compensate for these variations through post-processing. The SQUID needs to be cryogenically cooled to function. The SANSA SQUID is a High Temperature Superconductor (HTS) and operates using liquid nitrogen. Immersion cooling is used, as it is the simplest method, and produces the least amount of mechanical and electrical noise. Over time the liquid nitrogen will evaporate and needs to be replaced without significantly disrupting SQUID operations. A simple yet effective pumping scheme was developed that can transfer approximately 1.8 litres of liquid nitrogen every minute from a refill dewar. Monitoring of the liquid nitrogen level is an important management tool for a remote station, as refilling will be the primary reason for technicians to visit the site. The monitoring is achieved by placing the SQUID dewar on a specially designed non-magnetic load cell scale. The scale has been designed to limit the amount of tilting as the weight changes since this would also change the SQUID orientation. When a HTS SQUID is cooled in a large magnetic field, such as the Earth's field, Abrikosov vortices are likely to form in the superconducting material. As these vortices jump between pinning sites in the material, they increase the 1/f noise of the device and have been found to reduce the stability of the SQUID. Metal shields can be used to reduce the magnetic field, but are awkward to use and also reduce the magnitude of the signals of interest. In this thesis, a shielding method using Helmholtz coils is investigated. These coils are relatively simple and inexpensive to construct and do not attenuate the signals of interest. It was found that by cooling the SQUID in the reduced magnetic field, generated by the Helmholtz coils, the stability of the SQUID can be improved significantly. / AFRIKAANSE OPSOMMING: Die SQUID is die mees sensitiewe magneetveld sensors in die wêreld. Hierdie instrument kan slegs optimaal vir geometriese navorsing gebruik word indien dit ver van mensgemaakte magneetvelde opgestel word. Om die SQUID in 'n afgesonderde area op te stel veroorsaak verskeie probleme met betrekking tot infrastruktuur sover dit konstruksie, kragvoorsiening, en kriogeniese afkoeling aangaan. Hierdie tesis ondersoek moontlike oplossings vir die probleme en riglyne te ontwikkel vir die oprigting van toekomstige SQUID stasies. 'n Tipiese afgele SQUID observatorium bestaan gewoonlik uit 3 strukture wat 40m van mekaar opgestel is. Die beheerkamer bevat al die elektroniese apperaat, die kragkamer bevat 'n stel gereguleerde batterye wat deur sonpanele helaai word en DS krag verskaf aan die stasie en die SQUID-kamer wat deur middel van spoumure teen hitte gensoleer is. Die SQUID word op 'n gesoleerde pilaar geplaas om die invloed van vibrasies a.g.v. wind en wisselende buite temperature te verminder. Die temperatuur binne die SQUID kamer word ook noukeurig gemonitor aangesien wisseling in temperatuur geringe vervorming van die SQUID se montering kan veroorsaak wat 'n verandering van die SQUID se orintasie veroorsaak. Hierdie veranderings sal waargeneem word as stadige varirende sein in die SQUID se lesings. In beginsel is dit moontlik om vir dit te kompenseer deur middel van naprosessering. Die SQUID moet kriogenies afgekoel word om te funksioneer. Die SANSA SQUID is 'n Ho Temperatuur Supergeleier (HTS) en vloeibare stikstof word gebruik vir verkoeling. Afkoeling deur middel van indompeling word gebruik omdat dit die kleinste hoeveelheid meganiese en elektroniese versteuring veroorsaak. Die vloeibare stikstof verdamp mettertyd em moet vervang word sonder om die werking van die SQUID merkbaar te onderbreek. 'n Eenvoudige tog effektiewe oorpompstelsel is ontwikkel wat ongeveer 1.8 liter/minuut vloeibare stikstof vanuit 'n hervullings vakuum es kan oorpomp. Die meting van die vloeibare stikstof vlak is 'n belangrike aspek van die instandhouding van 'n afgele stasie aangesien dit die hoof rede sal wees vir tegnici om die perseel te besoek. Die meting word bewerkstellig deur die plasing van die SQUID se vakuum es op 'n spesiale ontwerpte, nie-magnetiese vrag sel skaal. Hierdie skaal is ontwerp om die mate van kanteling te beperk aangesien dit die orentasie van die SQUID kan benvloed. Wanneer 'n HTS SQUID binne in 'n groot magnetiese veld afgekoel word, is dit waarskynlik dat Abrikosov vortekse in die supergeleidende materiaal sal ontstaan. Soos hierdie vortekse rondspring in die materiaal vermeerder dit die 1/f ruis en daar is gevind dat die stabiliteit van die SQUID nadelig benvloed word. Metaal skilde kan gebruik word om die invloed van die magneetveld te verminder, maar is ongerie ik om te gebruik en verminder ook die sterkte van die seine wat waarneem wil word. In hierdie tesis word Helmholtz spoele ondersoek as 'n afskermings metode. Hierdie spoele is eenvoudig om te vervaardig en verminder nie die sterkte van waarneembare seine nie. Daar is gevind dat die stabiliteit van die SQUID merkbaar verbeter word deur afkoeling in 'n lae magnetiese veld soos bewerkstellig deur die Helmholtz spoele.

The intent of this thesis is to explore the design challenges and opportunities presented by the reintroduction of passenger rail to a small economically challenged New England city. Central to my thesis is that the advent of more efficient transportation options is not, in itself, enough: the infrastructure built to support those options must provide users with a comfortable, safe, and welcoming experience. The architecture of the rail station is critical in influencing that behavior and moving our society toward greater energy efficiency. Holyoke is a small mill city in western Massachusetts whose fortunes peaked in the early twentieth century and today struggles with decaying buildings and infrastructure, high unemployment, and significant poverty. The city also has many strengths, including relatively inexpensive hydro-electric power, sturdy adaptable mill buildings, an excellent location, strong neighborhood and civic pride, and a rich history on which to build. The city’s boosters feel that it is ripe for a renaissance already being driven by industry, the creative economy, telecommuters escaping the region’s major cities, and tourism. This research component of this thesis will explore: Current and historical demographic, industrial, and commercial context of the city and its passenger rail service, including usage projections, connections with various parts of the city, and Transit Oriented Design implications The needs of the adjacent Flats neighborhood for basic services and community space; strategies for attracting more consistent use of the station throughout its hours of operation by meeting the neighborhood residents’ needs Potential requirements for a station’s future capacity and adaptability – it will consider strategies for creating a flexible and adaptable building so as to meet the needs of the station and city as it changes over time Precedents that include rail stations and public buildings – it will investigate strategies used by effective public buildings The design component of this thesis incorporates the above research in developing site and program plans with a specific focus on design strategies that address accessibility, wayfinding, relevant services, and creating a welcoming gateway into the residential, industrial, and commercial heart of the city.