Dual nozzle aerodynamic and cooling analysis study

Geometric, aerodynamic flow field, performance prediction, and heat transfer analyses are considered for two advanced chamber nozzle concepts applicable to Earth-to-orbit engine systems. Topics covered include improvements to the dual throat aerodynamic and performance prediction program; geometric and flow field analyses of the dual expander concept; heat transfer analysis of both concepts, and engineering analysis of data from the NASA/MSFC hot-fire testing of a dual throat thruster model thrust chamber assembly. Preliminary results obtained are presented in graphs

Heterogene ouderenzorg in Scandinavië

De Nederlandse verzorgingsstaat verandert en om de transitie van verzorgingsstaat naar participatiesamenleving in goede banen te leiden wordt naar het buitenland gekeken. Het Scandinavische model heeft een voorbeeldfunctie, maar studenten van Professionshøjskolen Metropol (Kopenhagen) stellen de vraag of het Scandinavische model ooit voltooid en volledig uitgevoerd i

Spacial Equilibrium in a State Space Approach to Demand Uncertainty

Firms are likely to be uncertain about consumer preferences when launching products. The existing literature models preference uncertainty as an additive shock to the consumer distribution in a characteristic space model. The additive shock only shifts the mean of the consumers' ideal points. We generalize this approach to a state space model in which a vector of parameters can give rise to dierent distributions of consumer tastes in dierent states, allowing other moments of the consumer density to be uncertain. An equilibrium existence result is given. In the case of symmetric distributions, the unique subgame-perfect equilibrium can be described by a simple closed-form solution.Location; Product Dierentiation; Uncertainty; Hotelling

Uncertainty in Spatial Duopoly with Possibly Asymmetric Distributions: a State Space Approach

In spatial competition firms are likely to be uncertain about consumer locations when launching products either because of shifting demograph- ics or of asymmetric information about preferences. Realistically distri- butions of consumer locations should be allowed to vary over states and need not be uniform. However, the existing literature models location uncertainty as an additive shock to a uniform consumer distribution. The additive shock restricts uncertainty to the mean of the consumers loca- tions. We generalize this approach to a state space model in which a vector of parameters gives rise to different distributions of consumer tastes in dif- ferent states, allowing other moments (besides the mean) of the consumer distribution to be uncertain. We illustrate our model with an asymmetric consumer distribution and obtain a unique subgame perfect equilibrium with an explicit, closed-form solution. An equilibrium existence result is then given for the general case. For symmetric distributions, the unique subgame perfect equilibrium in the general case can be described by a simple closed-form solution.Location, Product Differentiation, Uncertainty, Hotelling

Dual nozzle aerodynamic and cooling analysis study

Analytical models to predict performance and operating characteristics of dual nozzle concepts were developed and improved. Aerodynamic models are available to define flow characteristics and bleed requirements for both the dual throat and dual expander concepts. Advanced analytical techniques were utilized to provide quantitative estimates of the bleed flow, boundary layer, and shock effects within dual nozzle engines. Thermal analyses were performed to define cooling requirements for baseline configurations, and special studies of unique dual nozzle cooling problems defined feasible means of achieving adequate cooling

POLY (1-TRIMETHYSILYL-1-PROPYNE) MEMBRANE REGENERATION PROCESS

A novel process for the regeneration of PTMSP membranes is disclosed. The regeneration process includes washing a fouled PTMSP membrane with a solution containing at least about 50% butanol in water for a time sufficient to increase the flux and/or selectivity of the membrane. This regeneration process with a butanol containing solution significantly improves both the flux and selectivity of the PTMSP membrane and can regenerate the flux of the PTMSP membrane to the level of a previously unused membrane

Public Participation Plan for Waste Area Group 7 Operable Unit 7-13/14 at the Idaho National Laboratory Site

This Public Participation Plan outlines activities being planned to: (1) brief the public on results of the remedial investigation and feasibility study, (2) discuss the proposed plan for remediation of Operable Unit 7-13/14 with the public, and (3) encourage public participation in the decision-making process. Operable Unit 7-13/14 is the Comprehensive Remedial Investigation/Feasibility Study for Waste Area Group 7. Analysis focuses on the Subsurface Disposal Area (SDA) within the Radioactive Waste Management Complex at the Idaho National Laboratory (Site). This plan, a supplement to the Idaho National Laboratory Community Relations Plan (DOE-ID 2004), will be updated as necessary. The U.S. Department of Energy (DOE), Idaho Department of Environmental Quality (DEQ), and U.S. Environmental Protection Agency (EPA) will participate in the public involvement activities outlined in this plan. Collectively, DOE, DEQ, and EPA are referred to as the Agencies. Because history has shown that implementing the minimum required public involvement activities is not sufficient for high-visibility cleanup projects, this plan outlines additional opportunities the Agencies are providing to ensure that the public’s information needs are met and that the Agencies can use the public’s input for decisions regarding remediation activities

Phase Transition Study of Superconducting Microstructures

The presented results are part of a feasibility study of superheated superconducting microstructure detectors. The microstructures (dots) were fabricated using thin film patterning techniques with diameters ranging from $50\mu$m up to $500\mu$m and thickness of $1\mu$m. We used arrays and single dots to study the dynamics of the superheating and supercooling phase transitions in a magnetic field parallel to the dot surface. The phase transi- tions were produced by either varying the applied magnetic field strength at a constant temperature or changing the bath temperature at a constant field. Preliminary results on the dynamics of the phase transitions of arrays and single indium dots will be reported.Comment: 7pages in LaTex format, five figures available upon request by [email protected], preprint Bu-He 93/

A systematic review of the effects of early separation on dairy cow and calf health

There is a growing concern from the public regarding early cow-calf separation, yet proponents of this practice maintain that artificial rearing is critical for cow and calf health. Early separation is assumed to reduce the risk of transfer of pathogens from dam to neonatal calf, but a wide range of health benefits associated with extended cow-calf contact has also been documented. The aim of this systematic review was to report and synthesize conclusions from the literature on dairy cow and calf health in conventional rearing versus cow-calf contact systems. Peer-reviewed, published manuscripts, written in English, directly comparing dairy cow or calf health in artificial versus suckling systems, were eligible for inclusion. We conducted 7-targeted searches using Web of Science (WoS) to identify key literature on important health conditions. The resulting manuscripts underwent a 4-step appraisal process, and further manuscripts were sourced from reference lists. This process resulted in a final sample of 70 articles that addressed cow and calf health. Sufficient literature was available to assess mastitis in cows, and scours, Cryptosporidiosis, Johne’s disease, pneumonia, immunity, and mortality in calves. The results for Cryptosporidiosis, pneumonia, immunity, and mortality were mixed, with some differences between studies likely attributable to flawed comparisons between cohorts. Overall, the articles addressing calf scours and mastitis pointed to beneficial or no effects of suckling. The studies addressing Johne’s disease did not find cow-calf contact to be a significant risk factor. In conclusion, the scientific peer-reviewed literature on cow and calf health provides no consistent evidence in support of early separation

Social housing improves dairy calves' performance in two cognitive tests

Early social housing is known to benefit cognitive development in laboratory animals. Pre-weaned dairy calves are typically separated from their dam immediately after birth and housed alone, but no work to date has addressed the effect of individual housing on cognitive performance of these animals. The aim of this study was to determine the effects of individual versus social housing on two measures of cognitive performance: reversal learning and novel object recognition. Holstein calves were either housed individually in a standard calf pen (n = 8) or kept in pairs using a double pen (n = 10). Calves were tested twice daily in a Y-maze starting at 3 weeks of age. Calves were initially trained to discriminate two colours (black and white) until they reached a learning criterion of 80% correct over three consecutive sessions. Training stimuli were then reversed (i.e. the previously rewarded colour was now unrewarded, and vice-versa). Calves from the two treatments showed similar rates of learning in the initial discrimination task, but the individually housed calves showed poorer performance in the reversal task. At 7 weeks of age, calves were tested for their response to a novel object in eight tests over a two-day period. Pair-housed calves showed declining exploration with repeated testing but individually reared calves did not. The results of these experiments provide the first direct evidence that individual housing impairs cognitive performance in dairy calves