Chemical evaluation of oil from field-and storage-damaged soybeans

In recent years, prolonged wet weather during the harvest season resulted in excessive field- and storagedamaged soybeans, particularly in the Southeast. As the severity of the damage increased, analysis of the oil extracted from these beans showed a corresponding increase in free fatty acids, Lovibond color, and content of oxidative deterioration products which absorb at 270 nm. In general, there was a substantial decrease in total oil content and an almost complete deterioration of phospholipids in severely damaged beans during storage. Initially, the oxidative stability of the oils decreased rapidly. After storage damage became severe, the stability increased substantially, possibly because of the formation of unidentified deterioration products which had high antioxidant properties. The study clearly showed that the processing of field- and storage-damaged soybeans would result in substantial refining losses to processors and that the finished oil would be of inferior quality. ARS, USDA     

Mean-Life Indifference Pricing for Quantity Purchases

Traditionally, consumers pay a fixed price for a quantity of items based on a presumed mean life. In many cases (i.e., federal government procurement) a sample of items is pretested to determine mean life and hence conformance to the contract. This paper suggests an alternative scheme based on a price indifference curve h(φ) which specifies the unit cost given mean life φ, which is estimated based on the actual performance of the first r items that fail. The paper develops a specific form for the indifference function and a procedure for estimating both φ and h(φ) and presents an example.     

Distributed model predictive control of an experimental four-tank system

A distributed model predictive control (DMPC) framework is proposed. The physical plant structure and the plant mathematical model are used to partition the system into self-sufficient estimation and control nodes. Local measurements at the nodes are used to estimate the relevant plant states. This information is then used in the model predictive control calculations. Communication among relevant nodes during estimation and control calculations provides improvement over the performance of completely decentralized controllers. The DMPC framework is demonstrated for the level control of an experimental four-tank system. The performance of the DMPC system for disturbance rejection is compared with other control configurations. The results indicate that the proposed framework provides significant improvement over completely decentralized MPC controllers, and approaches the performance of a fully centralized design.     

Mapping snow cover in the pan-Arctic zone,using multi-year (1998-2001) images from optical VEGETATION sensor

Timely information on spatial distribution and temporal dynamics of snow cover in the pan-Arctic zone is needed, as snow cover plays an important role in climate, hydrology and ecological processes. Here we report estimates of snow cover in the pan-Arctic zone (north of 45° N) at 1-km spatial resolution and at a 10-day temporal interval over the period of April 1998 to December 2001, using 10-day composite images of VEGETATION sensor onboard Système Pour l'Observation de la Terre (SPOT)-4 satellite. The results show that snow covered area (SCA) in North America (north of 45° N) increased from 1998 to 2001, while SCA in Eurasia (north of 45° N) decreased from 1998 to 2000 but increased in 2001. There were large spatial and temporal variations of snow cover in the pan-Arctic zone during 1998-2001.     

The effect of grain size, strain rate, and temperature on the mechanical behavior of commercial purity aluminum

Commercial purity aluminum AA1050 was subjected to equal channel angular extrusion (ECAE) that resulted in an ultrafine-grained (UFG) microstructure with an as-received grain size of 0.35 μm. This UFG material was then annealed to obtain microstructures with grain sizes ranging from 0.47 to 20 μm. Specimens were compressed at quasi-static, intermediate, and dynamic strain rates at temperatures of 77 and 298 K. The mechanical properties were found to vary significantly with grain size, strain rate, and temperature. Yield stress was found to increase with decreasing grain size, decreasing temperature, and increasing strain rate. The work hardening rate was seen to increase with increasing grain size, decreasing temperature, and increasing strain rate. The influence of strain rate and temperature is most significant in the smallest grain size specimens. The rate of work hardening is also influenced by strain rate, temperature, and grain size with negative rates of work hardening observed at 298 K and quasi-static strain rates in the smallest grain sizes and increasing rates of work hardening with increasing loading rate and grain size. Work hardening behavior is correlated with the substructural evolution of these specimens.     

Consistency and Reliability of Construction Arbitration Decisions: Empirical Study

While construction arbitration is analyzed in a plethora of information, there is a paucity of hard data about the consistency and reliability of the construction arbitration decision. The assumption that an industry familiar adjudicator will provide a reliable and consistent decision in comparison with the expectation of the industry as a whole has not been tested. This paper presents the results of a study on the reliability and consistency of construction arbitration through the examination of a variety of arbitrators’ decisions on the same construction dispute scenario. Data was collected from attorneys, owners, owner representatives, contractors, and subcontractors. Compilation of the survey results finds little consistency in the arbitrator’s awards, but with much thoughtful care in award consideration. The results suggest that the arbitrator’s industry background does not influence the arbitrator’s award. There is also no significant award bias due to the arbitrator’s education level or years spent in construction business. The results also indicate that previous arbitration experience does not predict the award outcome. This paper concludes that construction arbitration is wholly unpredictable. However, the result will be a well-reasoned and unbiased decision.     

Modeling the behavior of the 4/5ths rule for determining adverse impact: Reasons for caution.

The Equal Employment Opportunity Commission's 4/5ths rule has been used for over 20 years in applied psychology and employment law. The rule signals that there is adverse impact when the protected group selection ratio is less than 80% of the highest scoring group's selection ratio. We conducted several simulations and found, consistent with some previous management science literature, that the 4/5ths rule often resulted in false-positive readings of adverse impact even when there were no underlying (population) standardized group differences between subgroups. We then incorporated tests of statistical significance and found that adding such tests to the 4/5ths rule eliminated many false-positive indications of adverse impact. We also examined simulated selection systems based on meta-analytic values from the selection literature. The frequency of adverse impact signals from the 4/5ths rule increased markedly relative to simulations with no subgroup population differences. Adding statistical tests mitigated the number of indications of adverse impact to some extent. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Construction features and environmental factors influencingcorrosion on a self-contained fluid-filled submarine cable circuit inLong Island Sound

A 345 kV self-contained fluid-filled cable circuit was installed in an environment where corrosion of the armor may occur. To better understand the conditions that may result in corrosion, stray currents in the cable end zones and in the middle (submarine) of the circuit were measured, and cable samples were analyzed to determine the electrochemical activity of the cable's outer layers. The results of the project revealed that electrolytic corrosion would affect the semiconductive polyethylene if sufficient stray current density (greater than 0.15 A/m²) was induced by stray currents which were present in Long Island Sound where the cables are installed. Measurements revealed stray current densities in excess of this level towards one end of the cable route. Various other considerations for corrosion are also discussed     

Influence of hydroxyvalerate composition of polyhydroxy butyrate valerate (PHBV) copolymer on bone cell viability and in vitro degradation

The objective of this study was to elucidate the role of hydroxyvalerate (HV) composition in polyhydroxy butyrate valerate (PHBV) copolymer film on the degradation of copolymer and osteoblastic cell activity. Degradation was studied by monitoring time‐dependent changes in mass and chemical composition of the macroporous films. The mass loss of PHBV film upon 19 weeks of exposure to pH 7.4 phosphate buffer medium was found to range from 2.8% to 9.2% with a strong dependence on the original composition of the copolyester film and morphology. Tapping mode atomic force microscopy (TMAFM) was used to examine the roughness change of polyester films due to exposure to buffer medium. Chemical analysis of the degraded film was carried out using NMR to aid in the interpretation of the mass loss and TMAFM data. The NMR results showed a significant decrease in the mol % of HV content in the degraded PHBV film. Additionally, we established that UMR‐106 cell proliferation on macroporous PHBV matrix is minimally enhanced by the HV content of PHBV copolymer. Information provided by this study can be used in the selection of appropriate PHBV copolymer for clinical use where the biopolymer needs to remain physically intact and chemically unchanged during the intended period of biomedical application. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010