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The EXO-200 experiment searched for neutrinoless double-beta decay of $^{136}$Xe with a single-phase liquid xenon detector. It used an active mass of 110 kg of 80.6%-enriched liquid xenon in an ultra-low background time projection chamber with ionization and scintillation detection and readout. This paper describes the design and performance of the various support systems necessary for detector operation, including cryogenics, xenon handling, and controls. Novel features of the system were driven by the need to protect the thin-walled detector chamber containing the liquid xenon, to achieve high chemical purity of the Xe, and to maintain thermal uniformity across the detector., Manuscript updated in response to JINST reviewer comments

Dairy industries in Southeast Asia are small and produce less than the domestic market demands. As expenditure and population grow in Southeast Asia, it is expected that the expenditures on skim milk powder (SMP) will grow. In this study, we examined the competitiveness of US SMP in the Southeast Asian market with respect to other leading dairy exporters, including the European Union (EU-28), New Zealand, and Australia. Using monthly data from 2006 to 2015, Rotterdam models were used to estimate import demands for SMP in 4 Southeast Asian countries. In a scenario using annual averages from 2013 to 2015 as a baseline, our findings suggest that a 10% reduction in the US price of SMP would cause Indonesia, Singapore, Vietnam, and the Philippines SMP imports from the United States to increase by 3.96, 0.44, 2.68, and 1.94 kt, respectively. Under the same scenario, the value of US SMP imports would decrease for Indonesia, Vietnam, and the Philippines by $4.12, $2.93, and $2.48 million, respectively; however, the value of US SMP to Singapore would increase by $0.20 million. Singapore and Indonesia expenditures for the US SMP are elastic, which means that as expenditure and population in Southeast Asia continue to grow, a 1% increase in SMP expenditure in Singapore and Indonesia would result in 1.25 and 1.20% increases in US SMP exports.

A gravity model was used to determine the impact of exchange rate volatility on turkey trade flows. Previous analyses of aggregate agricultural sectors or products have assumed the effect of exchan...

Low-fat dairy products are key components of a healthy diet for all Americans. As the USDA increases its focus on nutrition and healthy eating, it is important to understand the underlying demands for dairy products, both the healthy and the less healthy ones. The consumption of fluid milk products has decreased over the last decade, whereas milk used for manufactured dairy products such as cheese, ice cream, yogurt, and butter, and for use as an ingredient in other food products, has risen. The objective of this study is to determine the effects of changes in demographic variables, retail prices, and total dairy expenditure on at-home consumption of dairy products, using purchase data from Nielsen 2007 Homescan (ACNielsen, New York, NY) data. To derive the demand elasticities for 16 products, a censored Almost Ideal Demand System model is used. Results reveal that demographic variables do have effects on the purchase of the 16 products, and own-price elasticities are 1 or greater for all 16 products for both uncompensated and compensated elasticities except 4: ice cream, refrigerated yogurt, processed cheese, and margarine. A substitution relationship exists among all fluid milk categories, natural and processed cheese, low-fat ice cream, and refrigerated yogurt, butter, and margarine.

The paper describes an improved hierarchical model for the assessment of high-level design quality attributes in object-oriented designs. In this model, structural and behavioral design properties of classes, objects, and their relationships are evaluated using a suite of object-oriented design metrics. This model relates design properties such as encapsulation, modularity, coupling, and cohesion to high-level quality attributes such as reusability, flexibility, and complexity using empirical and anecdotal information. The relationship or links from design properties to quality attributes are weighted in accordance with their influence and importance. The model is validated by using empirical and expert opinion to compare with the model results on several large commercial object-oriented systems. A key attribute of the model is that it can be easily modified to include different relationships and weights, thus providing a practical quality assessment tool adaptable to a variety of demands.

The Software Development System (SDS), a research program designed for the development of software for Ballistic Missile Defense software, is evolving toward increased capability in the areas of testing, quality assurance, and system-level definition. This paper discusses the evolution of SDS and plans for future development.

Software reuse has been demonstrated to increase productivity, reduce costs and improve software quality. Most research in the area of extraction of reusable code from legacy code has concentrated on code created in the functional decomposition paradigm. However, in recent years much object-oriented code has been written. This paper describes a knowledge-based approach to the identification of reusable components in object-oriented legacy code.

Object-oriented code is considered to be inherently more reusable than functional decomposition code; however, object-oriented code can suffer from a program understanding standpoint since good object-oriented style seems to require a large number of small methods. Hence code for a particular task may be scattered widely. Thus good semantics based tools are necessary. This paper describes an approach to object-oriented code understanding that focuses largely on informal linguistic aspects of code, such as comments and identifiers. >

A model for drainage flow has been developed using shallow fluid theory and considerations of entrainment of overlaying air and surface drage. Using explicit differencing techniques, a code was produced and applied to the nocturnal drainage flows in the complex valleys of the Geysers Geothermal Area of northern California.

Pulsation theory is discussed in light of recent improvements in the theory of radiative transfer and hydrodynamics with applications to Cepheids, RR Lyrae, and W Virginis stars.

Possible improvements to SOIL, an Eulerian hydrodynamics code that can do coupled radiation diffusion and strength of materials, are presented in this report. Our research is based on the inspection of other Eulerian codes and theoretical reports on hydrodynamics. Several conclusions from the present study suggest that some improvements are in order, such as second-order advection, adaptive meshes, and speedup of the code by vectorization and/or multitasking. 29 refs., 2 figs.

In a study of three 2D radiative transfer methods, equilibrium diffusion, nonequilibrium diffusion, and S/sub n/, as applied to the interaction of the reflected shock with a fireball near the surface, the following results were obtained. The equilibrium diffusion method requires modifications to transfer energy through optically thin zones. The present S/sub n/ method, as included in YAQUI-SN, i.e., the TWOTRAN code, has troubles in the treatment of a thick/thin interface. Improvements are possible using methods developed by I. Grant (J. Comput. Phys., v. 2, no. 4, 381-402(June 1968)) or D. Barfield (ibid., v. 10, no. 3, 420-431(Dec. 1972)). The nonequilibrium diffusion or moments method appears to be the most useful since it will limit properly in the optically thick and thin regions, but methods to determine the variable Eddington factors have not been successfully developed as yet. 7 figures.