Absolute stability analysis of attitude control systems for large boosters

Absolute stability analysis of attitude control systems for large launch vehicle

Annual Survey of Virginia Law: Criminal Law and Procedure

The past year has been an active one for the Virginia courts and General Assembly in the areas of criminal law and procedure. Developments include cases regarding the allowance of expert assistance to indigent criminal defendants and a defendant\u27s right to a new trial based on after-discovered evidence. Driving under the influence [DUI] defendants are no longer entitled to their choice of a blood or breath test as a function of the implied consent law, and for felons convicted of committing an offense after December 31, 1994, parole is no longer an option. This article surveys these and other legislative and judicial developments in Virginia criminal law. Although this article is intended to survey significant developments over the past year, the reader is cautioned to bear in mind several important caveats

An application of high authority/low authority control and positivity

Control Dynamics Company (CDy), in conjunction with NASA Marshall Space Flight Center (MSFC), has supported the U.S. Air Force Wright Aeronautical Laboratory (AFWAL) in conducting an investigation of the implementation of several DOD controls techniques. These techniques are to provide vibration suppression and precise attitude control for flexible space structures. AFWAL issued a contract to Control Dynamics to perform this work under the Active Control Technique Evaluation for Spacecraft (ACES) Program. The High Authority Control/Low Authority Control (HAC/LAC) and Positivity controls techniques, which were cultivated under the DARPA Active Control of Space Structures (ACOSS) Program, were applied to a structural model of the NASA/MSFC Ground Test Facility ACES configuration. The control systems design were accomplished and linear post-analyses of the closed-loop systems are provided. The control system designs take into account effects of sampling and delay in the control computer. Nonlinear simulation runs were used to verify the control system designs and implementations in the facility control computers. Finally, test results are given to verify operations of the control systems in the test facility

Westland/Hallmark: 2008 Beef Recall; A Case Study by The Food Industry Center

A Humane Society video, made secretly at the Westland/Hallmark plant in late 2007 and released in early 2008, led to the recall of 143 million pounds of beef. This case study illustrates the complexity of the food industry and the food recall process. Although ultimately, the incident had more to do with animal welfare than food safety — no sicknesses were tied to the recalled beef, it resulted in changes to the nation’s food safety procedures. The 2008 Westland/Hallmark beef recall, the largest beef recall in U.S. history, is a stepping-off point to examine the beef supply chain generally and the ground beef supply chain specifically.Agribusiness, Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,

Kroger Co. v. Morris: The Diminution of Hearing Officers

In Kroger Co. v. Morris the Court of Appeals of Virginia reached two contradictory conclusions. On one hand the court held that the Virginia Workers\u27 Compensation Commission could overrule a deputy commissioner\u27s fact findings based solely on evidence contained in the record below. On the other hand, the court concluded that it was itself unable to make such fact findings based solely on the record

NASA/MSFC ground experiment for large space structure control verification

Marshall Space Flight Center has developed a facility in which closed loop control of Large Space Structures (LSS) can be demonstrated and verified. The main objective of the facility is to verify LSS control system techniques so that on orbit performance can be ensured. The facility consists of an LSS test article which is connected to a payload mounting system that provides control torque commands. It is attached to a base excitation system which will simulate disturbances most likely to occur for Orbiter and DOD payloads. A control computer will contain the calibration software, the reference system, the alignment procedures, the telemetry software, and the control algorithms. The total system will be suspended in such a fashion that LSS test article has the characteristics common to all LSS

Factors affecting paternal adjustment during the transition to parenthood

An emerging body of research is identifying factors which put individuals at risk for experiencing a difficult adjustment during the transition to parenthood. The purpose of this study was to test a model for the prediction and identification of paternal risk factors. Forty seven couples expecting their first child were the subjects. Questionnaires which assessed paternal expectations regarding parenthood and prenatal marital satisfaction were administered in the third trimester of their wife\u27s pregnancy. Two months postpartum, a second questionnaire was administered which included measures of paternal violated expectations, paternal postpartum marital satisfaction, paternal stress, infant temperament, maternal marital satisfaction, maternal postpartum depression, the presence of external support and maternal change in employment status. Multiple regression analyses were conducted to identify which variables significantly predicted the presence of postpartum paternal stress. In general, two hypotheses were supported. Paternal postpartum stress was predicted by (1) higher quality of paternal marital satisfaction assessed prenatally, and (2) infants\u27 whose temperaments were paternally assessed as slowly adaptable, less persistent, and more distractable. Statistically significant bivariate correlations were also identified among the predictor variables. Paternal prenatal marital satisfaction was positively correlated with maternal and paternal postpartum marital satisfaction, and a higher incidence of paternal violated expectations. A higher quality of maternal marital satisfaction was correlated with a lower incidence of maternal postpartum depression. Various infant temperament subscales were correlated with other temperament subscales and with some of the predictor variables. The clinical and research implications associated the findings of this study were discussed

2007 Supermarket Panel Report

Replaced with revised version of paper 12/16/10.Agribusiness, Industrial Organization,

THE 2003 SUPERMARKET PANEL ANNUAL REPORT

Executive Summary The Food Industry Center established the Supermarket Panel in 1998 as the basis for an ongoing study of the supermarket industry. Since 2000 the core of the Panel has been a random sample of stores drawn from the approximately 32,000 supermarkets in the U.S. that accept food stamps. The purpose of collecting data on supermarket operations and performance is to: Provide timely, useful information for the industry through benchmark reports and annual summaries, trends on key indices of technology adoption, competitive positions and performance. Be a ready source of data for research on current and emerging issues - to be able to track the changes in operation and its impacts on performance over time. This report presents findings from the 2003 Supermarket Panel, and provides an overview of findings from the past four years. The 2003 Panel includes 391 stores that are a representative cross-section of the supermarket industry. The Panel tries to follow the same stores over time. Of the 391 stores, 268 were in the Panel in 2002. Nine percent of the stores have been in the Panel all four years. At least one store from every state is in the Panel. New in 2003 The Panel was offered over the Internet. Forty-seven percent responded on-line. An index on variety offering was created. Questions about offering irradiated fresh ground beef are included (with a follow up study). Supply Chain Technology Practices The Supply Chain Score measures the extent to which stores have adopted computerized methods of communicating with suppliers, handling inventory management, ordering, invoicing, and analyzing consumer purchases. The average score has almost doubled in four years. Stores in groups (chains) with more than 750 stores and/or supercenter formats have adopted supply chain practices most intensively. Internet/Intranet is used by at least two-thirds of all stores; over ninety percent of stores in groups with more than 50 stores use this technology. Vendor managed inventory has been adopted by only 42 percent of stores in the biggest store groups with much lower rates of adoption in smaller store groups. A higher Supply Chain Score benefited significantly higher sales per labor hour. Service and Variety Scores About eighty percent of stores in all size groups offer bagging and custom meat cutting. Variety pays off in better performance for five out of eight measures. Variety helps to grow annual percentage sales. Supercenters/Top Stores/Unions Supercenters have significantly higher sales per labor hour and per transaction. They have lower sales growth. Fifty-three percent of supermarkets face supercenter competition. They have somewhat higher sales per square foot of selling area and higher annual sales growth than stores that do not face supercenter competition. Eleven percent of stores in the 2003 Panel qualified as "top stores." They had above the median levels for each of three performance measures: weekly sales per square foot, sales per labor hour, and annual percentage sales growth. Top stores are more likely to have a unionized labor force, be a price and variety leader, and be wholesaler supplied. One-third of 2003 Panel stores have unionized labor. These stores have more productive labor with significantly higher sales per labor hour. Statistically Significant Drivers of Performance Over Time The descriptive profile and analysis of the Panel provide useful insights on the structure of the supermarket industry and factors associated with strong performance. However, statistical regression analysis identifies whether a variable is significantly correlated with a performance measure holding all else constant. This section presents findings from a multivariate regression analysis of five key performance measures. These regression analyses are summarized on the table below. If a characteristic is listed on the table it was a significant correlate in at least three out of the past four years. For example, in the last row, the only variable that was consistently significant for increasing annual percentage sales growth is being in an area with higher household incomes. Having a warehouse format decreased sales growth and three other factors were significant in at least three years but alternated with positive and negative effects.Industrial Organization, Marketing,