Calculation of a circular jet in crossflow with a multiple-time-scale turbulence model

Numerical calculation of a three dimensional turbulent flow of a jet in a crossflow using a multiple time scale turbulence model is presented. The turbulence in the forward region of the jet is in a stronger inequilibrium state than that in the wake region of the jet, while the turbulence level in the wake region is higher than that in the front region. The calculated flow and the concentration fields are in very good agreement with the measured data, and it indicated that the turbulent transport of mass, concentration, and momentum is strongly governed by the inequilibrium turbulence. The capability of the multiple time scale turbulence model to resolve the inequilibrium turbulence field is also discussed

Modification of the ECAS reference steam power generating plant to comply with the EPA 1979 new source performance standards

Detailed capital cost estimates for the ECAS and modified reference plants in mid-1978 dollars for both 250 and 175 F (394 and 353 K) stack gas reheat temperatures based on the cost estimates developed for the ECAS study are presented. The scope of the work included technical assessment of sulfur dioxide scrubber system design, on site calcination versus purchased lime, reheat of stack gas, effect of sulfur dioxide scrubber on particulate emission, and control of nitrogen oxides

Hepatitis in refugees who settle in Australia

Copyright to Australian Family Physician. Reproduced with permission. Permission to reproduce must be sought from the publisher, The Royal Australian College of General Practitioners.BACKGROUND The World Health Organisation estimates that 2 billion people have been infected with hepatitis B and about 180 million people infected with hepatitis C worldwide. More than 350 million have chronic hepatitis B and 130 million have chronic hepatitis C infection. Most infections of hepatitis B and C are from unsafe injection practices, both medical and nonmedical; from household contacts; or, in the case of hepatitis B, from ‘vertical’ transmission from mother to child. OBJECTIVE This article discusses screening and management of hepatitis B and C in refugees who settle in Australia. DISCUSSION Most people carrying hepatitis will be asymptomatic with infection detected by screening. Refugees need counselling, education and support to come to terms with the implications of hepatitis B and C for both themselves and their families. In Australia both viruses can be treated in those with active infection and general practitioners can be involved in diagnosis, follow up and shared care management.Jill Benson, William Donohu

Hardware fault insertion and instrumentation system: Mechanization and validation

Automated test capability for extensive low-level hardware fault insertion testing is developed. The test capability is used to calibrate fault detection coverage and associated latency times as relevant to projecting overall system reliability. Described are modifications made to the NASA Ames Reconfigurable Flight Control System (RDFCS) Facility to fully automate the total test loop involving the Draper Laboratories' Fault Injector Unit. The automated capability provided included the application of sequences of simulated low-level hardware faults, the precise measurement of fault latency times, the identification of fault symptoms, and bulk storage of test case results. A PDP-11/60 served as a test coordinator, and a PDP-11/04 as an instrumentation device. The fault injector was controlled by applications test software in the PDP-11/60, rather than by manual commands from a terminal keyboard. The time base was especially developed for this application to use a variety of signal sources in the system simulator

New collections of p-subgroups and homology decompositions for classifying spaces of finite groups

Let G be a finite group and p a prime dividing its order. We define new collections of p-subgroups of G. We study the homotopy relations among them and with the standard collections of p-subgroups. We determine their ampleness and sharpness properties.Comment: 14 pages, some revisions made, final version to appear in Communications in Algebr

ANALYSIS OF THE RISK MANAGEMENT PROPERTIES OF GRAZING CONTRACTS VERSUS FUTURES AND OPTION CONTRACTS

A stochastic budget simulator and generalized stochastic dominance are used to compare the risk management properties of grazing contracts to futures and option contracts. The results show that the risks of backgrounding feeder cattle are reduced significantly for pasture owners in a grazing contract. However, the risks of the cattle owner in a grazing contract are not significantly reduced. The results show that generally risk adverse pasture owners prefer grazing contracts to integrated production when traditional hedging is used to manage price risks. In addition, grazing contracts compare favorably with put option contracts for some pasture owners.Backgrounding, Futures contracts, Grazing contracts, Options contracts, Risk management, Risk and Uncertainty,

Integrated assurance assessment of a reconfigurable digital flight control system

The integrated application of reliability, failure effects and system simulator methods in establishing the airworthiness of a flight critical digital flight control system (DFCS) is demonstrated. The emphasis was on the mutual reinforcement of the methods in demonstrating the system safety

Progress in Technology Validation of the Next Ion Propulsion System

The NASA's Evolutionary Xenon Thruster (NEXT) ion propulsion system has been in advanced technology development under the NASA In-Space Propulsion Technology project. The highest fidelity hardware planned has now been completed by the government/industry team, including a flight prototype model (PM) thruster, an engineering model (EM) power processing unit, EM propellant management assemblies, a breadboard gimbal, and control unit simulators. Subsystem and system level technology validation testing is in progress. To achieve the objective Technology Readiness Level 6, environmental testing is being conducted to qualification levels in ground facilities simulating the space environment. Additional tests have been conducted to characterize the performance range and life capability of the NEXT thruster. This paper presents the status and results of technology validation testing accomplished to date, the validated subsystem and system capabilities, and the plans for completion of this phase of NEXT development

Application of remote sensing to selected problems within the state of California

There are no author-identified significant results in this report

Application of remote sensing to selected problems within the state of California

There are no author-identified signficant results in this report