In the current study a variable speed pump controlled hydrostatic circuit where an underlapped shuttle valve is utilized to compensate the unequal flow rate of a single rod actuator is analyzed. Parameters of the shuttle valve are included in the system analysis, rather than treating it as an ideal switching element as handled in literature. A linearized model of the system is obtained. An inverse kinematic model, which calculates the required pump drive speed for a desired actuator speed and given pilot pressure input, is formed. A numerical stability analysis program is developed, and the stability of all possible shuttle valve spool positons is determined. The theoretical findings are validated by non-linear simulation model responses.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Within the industry, telemetry receivers are used in ground-based telemetry receiving stations to receive telemetry data from air or space-based sources. Equipment for the typical telemetry application is widely available. But when requirements create the need for a space-based telemetry receiver to uplink data from the ground, what are the choices for equipment? In such situations, adapting COTS equipment may present the only solution to meet delivery and budgetary constraints. The first part of this paper provides technical and contractual points a COTS supplier needs to consider when bidding on a COTS contract. The second part of this paper covers a project concerned with modification of a general-purpose ground telemetry receiver for use on the International Space Station. The information within the paper is useful to other engineers and companies considering contracts to modify COTS equipment for use on Shuttle or other space-based projects.

Master of Agribusiness / Department of Agricultural Economics / Mykel Taylor / The agricultural commodity market has been experiencing previously unseen high prices in recent years. This new era of prices brings with it new challenges within agriculture for farmers and grain buyers within agriculture. This research explores the basis values of hard red winter wheat in Kansas and the elevator characteristics that provide a competitive advantage for elevators buying wheat in Kansas. This research explores hard red winter wheat basis values from elevators located around Kansas from 2002 to 2013. Two hundred twenty eight locations from around Kansas were used in the research. These locations provided the price data that was used for this research. The elevator characteristics used in the research were collected from the Kansas Grain and Feed Directory and the Burlington Northern-Santa Fe and Union Pacific railway companies. Five elevator characteristics were researched that may have a significant impact on an elevators basis. These characteristics are thought to provide a competitive advantage to the location in the form of stronger or narrower basis bids to the farmer, giving the farmer a higher price for his grain. The characteristics researched included elevator capacity, transportation capabilities, elevator terminal status, shuttle loading status, and cooperative or investor-owned business structure. Each characteristic was compared against their counterpart. For example, a location is either a shuttle loader or it is not. The research provides grain companies and farmers some data that they may find useful in marketing grain and setting basis levels in the ever changing and volatile market place in today’s grain industry.

Hoje em dia, a maioria das operações de alívio é feita utilizando um sistema de posicionamento dinâmico (DP). O sistema DP permite controlar a posição relativa entre o navio aliviador e o FPSO (Floating Production Storage and Offloading), trazendo desta forma muitas vantagens à operação. Neste tipo de operação os dois corpos flutuantes precisam ficar muito próximos um do outro em alto-mar, aumentando de forma significativa a interação hidrodinâmica entre eles. Quando um corpo está no mar ele se torna uma barreira à propagação das ondas, distorcendo o campo de ondas ao redor. Este efeito é chamado de efeito de sombra de onda ou simplesmente efeito de sombra. O efeito de sombra depende do comprimento de onda, do tamanho do corpo que o está criando e da direção de propagação da onda. O efeito de sombra altera de forma significativa a distribuição de energia das ondas do mar na região do fenômeno, alterando desta forma, o comportamento do corpo que está sob a influência do mesmo. Com o comportamento do corpo alterado é esperado que o sistema DP se comporte de forma diferente quando sob influência do efeito de sombra. Este trabalho se propõe a estudar a influência que o efeito de sombra causa no sistema DP, visando obter dados para melhorar os projetos de sistema DP. / Nowadays, a great number of offloading operations is carried out using a dynamic positioning (DP) system. The DP system allows the position between the shuttle tanker (ST) and the FPSO platform (Floating Production Storage and Offloading) to be controlled, bringing several advantages to the operation. In this kind of operation the two vessels must be kept very close in the sea, increasing significantly the hydrodynamic interaction effects between them. When a body is floating at the sea, it turns into a barrier to the wave propagation, disturbing the wave field around it. This effect is called shielding effect or shielding area. The shielding area depends on the wave length, the size of the body and the wave direction. The shielding area significantly disturbs the energy of the wave field nearby the FPSO. Because of that, it is expected that the shuttle tanker presents a different hydrodynamic behavior. The purpose of this work is to study the influence of the shielding area on the DP system, trying to obtain data to improve DP systems design.

No description available.

Thesis (M.S.)--Michigan State University. Dept. of Geography, 2008. / Title from PDF t.p. (Proquest, viewed on Aug. 10, 2009) Includes bibliographical references (p. 191-201). Also issued in print.

Hoje em dia, a maioria das operações de alívio é feita utilizando um sistema de posicionamento dinâmico (DP). O sistema DP permite controlar a posição relativa entre o navio aliviador e o FPSO (Floating Production Storage and Offloading), trazendo desta forma muitas vantagens à operação. Neste tipo de operação os dois corpos flutuantes precisam ficar muito próximos um do outro em alto-mar, aumentando de forma significativa a interação hidrodinâmica entre eles. Quando um corpo está no mar ele se torna uma barreira à propagação das ondas, distorcendo o campo de ondas ao redor. Este efeito é chamado de efeito de sombra de onda ou simplesmente efeito de sombra. O efeito de sombra depende do comprimento de onda, do tamanho do corpo que o está criando e da direção de propagação da onda. O efeito de sombra altera de forma significativa a distribuição de energia das ondas do mar na região do fenômeno, alterando desta forma, o comportamento do corpo que está sob a influência do mesmo. Com o comportamento do corpo alterado é esperado que o sistema DP se comporte de forma diferente quando sob influência do efeito de sombra. Este trabalho se propõe a estudar a influência que o efeito de sombra causa no sistema DP, visando obter dados para melhorar os projetos de sistema DP. / Nowadays, a great number of offloading operations is carried out using a dynamic positioning (DP) system. The DP system allows the position between the shuttle tanker (ST) and the FPSO platform (Floating Production Storage and Offloading) to be controlled, bringing several advantages to the operation. In this kind of operation the two vessels must be kept very close in the sea, increasing significantly the hydrodynamic interaction effects between them. When a body is floating at the sea, it turns into a barrier to the wave propagation, disturbing the wave field around it. This effect is called shielding effect or shielding area. The shielding area depends on the wave length, the size of the body and the wave direction. The shielding area significantly disturbs the energy of the wave field nearby the FPSO. Because of that, it is expected that the shuttle tanker presents a different hydrodynamic behavior. The purpose of this work is to study the influence of the shielding area on the DP system, trying to obtain data to improve DP systems design.

Context: Increased physical activity participation and fitness are cardioprotective. The EUROACTION trial demonstrated that a preventive cardiology programme significantly increased self-reported physical activity participation (Wood et al., 2008). Objective: The EUROACTION Physical Activity and Fitness (EPAF) Study aimed to objectively evaluate the effectiveness of the EUROACTION physical activity and exercise intervention at increasing physical activity participation and fitness in people with coronary artery disease (COR) and those at high risk of developing cardiovascular disease (HRI) compared to standard care. Study design: A nested study within a paired cluster randomised controlled trial in eight European countries. Methodology: 12 pairs of centres (12 hospitals and 12 general practices) were randomised to receive the EUROACTION programme (INT) or be monitored for usual care (UC). In the INT hospitals, COR patients participated in a 16-week supervised exercise programme and a home-based activity intervention, delivered by a physiotherapist. In INT general practice nurses were trained to deliver personalised physical activity advice to HRI. Outcome measures: Objective physical activity participation was measured by mean number of steps per day (Yamax Digiwalker SW200 pedometer). Fitness was determined by the Incremental Shuttle Walk Test (ISWT) [hospital centres] and Chester Step Test (CST) [general practice centres]). Results: The mean number of steps in COR patients at 1–year was significantly higher in INT (+2310 steps, 95% CI +1226 to +3394 steps; P=0.003). The difference in cardiorespiratory fitness (ISWT) exceeded the minimal clinically important difference but was not statistically significant (+54 metres [95% CI - 102.8 to +211.0 metres]; P=0.42). In general practice centres, whilst no significant differences were found at 1 year in mean steps per day (+982 steps, 95% CI -569 to +2533 steps) and cardiorespiratory fitness (CST) at 1-year (+0.93 minutes, 95% CI -0.62 to +2.48 minutes), there was a difference in the change over time in fitness in favour of the INT (+0.94 mins [95% CI +0.23 to +1.66 mins]; P=0.02). Marked heterogeneity impacted on statistical power. All differences observed represented clinically important differences. Conclusion: The EPAF-Study has demonstrated that the EUROACTION programme was effective at increasing physical activity participation but objective measures indicate to a lesser degree than the self-reported physical activity outcomes previously published. Clinically important differences in objectively measured physical activity participation and cardiorespiratory fitness suggest further research, which is sufficiently powered, is warranted.

The development of the new cathode and anode materials of Lithium-Ion Batteries (LIBs) with high energy density and outstanding electrochemical performance is of substantial technological importance due to the ever-increasing demand for economic and efficient energy storage system. Because of the abundance of element sulfur and high theoretical energy density, Lithium-Sulfur (Li-S) batteries have become one of the most promising candidates for the next-generation energy storage system. However, the shuttling effect of electrolyte-soluble polysulfides severely impedes the cell performance and commercialization of Li-S batteries, and significant progress have been made to mitigate this shuttle effect in the past two decades. Coordination polymers (CPs) or Metal-organic Frameworks (MOFs) have been attracted much attention by virtue of their controllable porosity, nanometer cavity sizes and high surface areas, which supposed to be an available material in suppressing polysulfide migration. In this thesis, we investigate different mechanisms of mitigating polysulfide diffusion by applying a layer of MOFs (including Y-FTZB, ZIF-7, ZIF-8, and HKUST-1) on a separator. We also fabricate a new free-standing 2D coordination polymer Zn2(Benzimidazolate)2(OH)2 with rich hydroxyl (OH-) groups by using a simple, scalable and low cost method at air/water surface. Our results suggest that the chemical stability, the cluster morphology and the surface function groups of MOFs shows a greater impact on minimizing the shuttling effect in Li-S batteries, other than the internal cavity size in MOFs. Meanwhile, the new design of 2D coordination polymer efficiently mitigate the shuttling effect in Li-S battery resulting in a largely promotion of the battery capacity to 1407 mAh g-1 at 0.1 C and excellent cycling performance (capacity retention of 98% after 200 cycles at 0.25C). Such excellent cell performance is mainly owing to the fancying physical and chemical structure controllability of MOFs or CPs, which has substantial potential for future commercial utilizations.

In the current study a variable speed pump controlled hydrostatic circuit where an underlapped shuttle valve is utilized to compensate the unequal flow rate of a single rod actuator is analyzed. Parameters of the shuttle valve are included in the system analysis, rather than treating it as an ideal switching element as handled in literature. A linearized model of the system is obtained. An inverse kinematic model, which calculates the required pump drive speed for a desired actuator speed and given pilot pressure input, is formed. A numerical stability analysis program is developed, and the stability of all possible shuttle valve spool positons is determined. The theoretical findings are validated by non-linear simulation model responses.