23,194 research outputs found

    Control jet placement on spacecraft

    Get PDF
    For efficient operation and configuration design of multijet spacecraft control systems methods of linear programming are used to select combinations of individual jet-burn times which produce the desired impulses. Minimum-fuel and fuel-time solutions are found

    Measures of Gasoline Price Change

    Get PDF
    [Excerpt] No prices are more visible to the public than gasoline prices. Even for people who don’t have to fill up a tank on a regular basis, gasoline prices are likely to be in their view, posted every day. In addition, no prices have more of an impact on short-run movements in the Consumer Price Index (CPI). Gasoline prices are so much more volatile than other CPI components that, even though gasoline makes up less than 6 percent of the CPI, it is often the main source of monthly price movements in the all items index. Moreover, because they are so visible and gasoline is purchased so frequently, gasoline prices have a major impact on the perception of prices. Constantly seeing prices at the pump creep ever higher will often create a perception of broader inflation—and, of course, higher gasoline prices are likely to eventually have an impact on other prices as transportation costs increase. So, it is particularly important that gasoline price changes be measured accurately and reliably. Fortunately, gasoline is one of the few consumer goods for which there are many sources of price data. In fact, the ease of price collection makes it feasible for other government agencies and even private sources to create reliable measures. On the government side, the Energy Information Administration (EIA) publishes extensive gasoline price data. Among private sources are the American Automobile Association, the Oil Price Information Service, and the Lundberg Survey. Furthermore, gasoline is one of the few nonfood items for which the Bureau of Labor Statistics (BLS) publishes an average price series as well as an index; the fact that gasoline is a relatively homogenous product makes meaningful average price data possible. This article examines three measures of gasoline prices: the BLS Consumer Price Index for All Urban Consumers (CPI-U) U.S. city average for all types of gasoline, the BLS CPI average price series for all types of gasoline, and the EIA Weekly Retail Gasoline and Diesel Prices for all grades of gasoline. The purpose of the article is to identify how these measures have behaved over the 10-year period from December 2002 to December 2012

    Connection and coherence between and among European instruments in the private international law of obligations

    Get PDF
    This article considers points of connection and coherence between and among the Rome I Regulation, the Rome II Regulation, and Regulation 1215, and relevant predecessor instruments. The degree of consistency in aim, design and detail of conflict of laws rules is examined, vertically (between/among consecutive instruments) and horizontally (across cognate instruments). Symbiosis between instruments is explored, as is the interrelationship between choice of court and choice of law. Disadvantaged parties, and the cohesiveness of their treatment under the Regulations, receive particular attention

    Death of a salesman

    Get PDF
    First paragraph: In December 2012 Australia became the first jurisdiction to mandate plain (or standardised) packaging for tobacco products. Many governments have been looking on with interest, anxious to learn if this is also the next step forward in their own efforts to tackle the harms caused by tobacco. This special issue begins to answer this question by presenting a series of studies which provide an initial evaluation of the policy. What have been the early impacts of plain packaging on young people and adult smokers? And are there any unintended consequences—has it reduced prices, for instance, or encouraged illicit tobacco use

    Being With Friends and the Potential for Binge Drinking During the First College Semester

    Get PDF
    In this prospective study, we assess the relationship between being with high school friends during the college transition and binge drinking. Across analyses (n = 489), the presence of high school friends during the college transition was associated with reduced binge drinking at the end of the first college semester among individuals at risk for this behavior because they drank in high school, associated alcohol use with the student role, or engaged in binge drinking at the beginning of the fall term. This is consistent with research linking social integration to behavioral regulation and suggests the presence of high school friends during the college transition serves as a source of social control at a juncture characterized by a reduction in normative constraint. Implications for practitioners seeking to assess new students\u27 risks for binge drinking and to more effectively meet the needs of vulnerable groups are discussed in relation to the study results

    Individual and Society: Sociological Social Psychology

    Get PDF
    Unlike the few other texts for undergraduate sociological social psychology courses that present 3 distinct traditions (or faces ) ... Symbolic Interactionist (SI), Social Structure and Personality (SSP), and Group Processes and Structure (GPS) by topic alone, this text initially discusses these faces by research tradition, and emphasizes the different theoretical frameworks within which social psychological analyses are conducted. With this approach, the authors make clear the link between face of sociological social psychology, theory, and methodology. And students gain an appreciably better understanding of the field of sociological social psychology; how and why social psychologists trained in sociology ask particular kinds of questions; the types of research they are involved in; and how their findings have been, or can be, applied to contemporary societal patterns and problems. Great writing makes this approach successful and interesting for students, resulting in a richer, more powerful course experience. A website offers instructors high quality support material, written by the authors, which you will appreciate and value -- Provided by publisher

    Written evidence to Justice Committee, Family Law (Scotland) Act 2006, Post-legislative Scrutiny

    Get PDF
    No abstract available

    RinRuby: Accessing the R Interpreter from Pure Ruby

    Get PDF
    RinRuby is a Ruby library that integrates the R interpreter in Ruby, making R's statistical routines and graphics available within Ruby. The library consists of a single Ruby script that is simple to install and does not require any special compilation or installation of R. Since the library is 100% pure Ruby, it works on a variety of operating systems, Ruby implementations, and versions of R. RinRuby's methods are simple, making for readable code. This paper describes RinRuby usage, provides comprehensive documentation, gives several examples, and discusses RinRuby's implementation. The latest version of RinRuby can be found at the project website: http://rinruby.ddahl.org/.

    Looking Beyond the Marketing Claims of New Beverages: Health Risks of Consuming Sports Drinks, Energy Drinks, Fortified Waters, and Other Flavored Beverages

    Get PDF
    Consumption of several new categories of beverages has increased significantly in recent years. Sold in cans and bottles in many venues and heavily marketed as health and strength enhancing, these beverages have become popular among children and adolescents as well as adults. Energy drinks, sports drinks, fruit drinks, flavored waters, and sweetened teas and coffees are known collectively as fortified beverages due to the natural and artificial ingredients that are added in the processing of their main ingredient, water. In view of their rising popularity, it is important to assess the healthfulness of these beverages and the implications of their consumption by the general public. Consumption by youth, to whom marketing is often targeted, is of particular interest in view of children's potentially increased vulnerability to chemicals and other added substances. Further, the possible contribution of these beverages to the high prevalence of childhood obesity merits attention.This report will discuss the major categories of fortified beverages, presenting data on their nature, their ingredients, their similarities and differences, the possible effects on children of their consumption, and areas for further research

    Space shuttle post-entry and landing analysis. Volume 2: Appendices

    Get PDF
    Four candidate navigation systems for the space shuttle orbiter approach and landing phase are evaluated in detail. These include three conventional navaid systems and a single-station one-way Doppler system. In each case, a Kalman filter is assumed to be mechanized in the onboard computer, blending the navaid data with IMU and altimeter data. Filter state dimensions ranging from 6 to 24 are involved in the candidate systems. Comprehensive truth models with state dimensions ranging from 63 to 82 are formulated and used to generate detailed error budgets and sensitivity curves illustrating the effect of variations in the size of individual error sources on touchdown accuracy. The projected overall performance of each system is shown in the form of time histories of position and velocity error components
    • …
    corecore