3,897 research outputs found
Coplanar interconnection module
Module for interconnecting a semiconductor array to external leads or components incorporates a metal external heat sink for cooling the array. Heat sink, extending down from the molded block that supports the array, is immersed in a liquid nitrogen bath which is designed to maintain the desired array temperature
Mammals of Southwestern Arkansas Part II. Rodents
This study investigated the composition and habitat affinities of the mammalian fauna of southwestern Arkansas. The study area was comprised of the 21 counties located south and/or west of and including Pulaski County. The previously existing data set pertaining to the mammals of Arkansas was notably incomplete and this study area in particular, was poorly known mammalogically. Specimens were collected by standard trapping and salvage methods throughout the study area. The mammals considered during this study were limited to those species meeting a set of criteria designed to eliminate species that had been introduced or artificially maintained. This study has accumulated records of 25 species of rodents; over 1500 specimens have been recorded; and a total of 95 new county records have been documented
The wear of materials in hydraulic transport pipelines
Bibliography: leaves 60-68.The hydraulic transportation of particulate solids through pipelines results in wear of the pipeline walls. The lifetime of the pipeline is determined by this rate of material loss and is therefore critical to the designer. Due to the small amounts of material lost in in-situ tests, requiring in many cases in excess of 1000 hours testing, an accelerated test procedure is necessary. This work introduces an accelerated method of evaluating materials under simulated pipeline wear conditions. The solids in the slurry and the materials were closely monitored to attain an understanding of their interaction. The wear rate of the materials tested was found to decrease with a decrease in the average rounding of the particles. These changes in particle characteristics occur with time due to comminution within the pump and pipeline. The mechanical properties and wear rates of the materials evaluated were examined to determine whether any relationships existed
Study of cryogenic propellant systems for loading the space shuttle
Computer programs were written to model the liquid oxygen loading system for the space shuttle. The programs allow selection of input data through graphic displays which schematically depict the part of the system being modeled. The computed output is also displayed in the form of graphs and printed messages. Any one of six computation options may be selected. The first four of these pertain to thermal stresses, pressure surges, cooldown times, flow rates and pressures during cooldown. Options five and six deal with possible water hammer effects due to closing of valves, steady flow and transient response to changes in operating conditions after cooldown. Procedures are given for operation of the graphic display unit and minicomputer
Cooldown time for simple cryogenic pipelines
Cooldown time for simple cryogenic pipeline
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Measuring children and young people's wellbeing in the school context
Although being rooted in the work of ancient Greek philosophers, contemporary research on wellbeing is a relatively new phenomenon. As a term in the literature, wellbeing is often used interchangeably with others, such as happiness, flourishing, enjoying a good life, and life satisfaction. Furthermore the wellbeing of school-aged children is only beginning to be explored with increasing recognition that research conducted on adults cannot be uncritically applied to children and young people. This paper aims to address some of the complexities in conceptualising, and hence assessing, children and young people’s wellbeing by drawing on a recently completed study examining the role of creative initiatives in fostering wellbeing. The new instrument that was developed to capture children and young people’s perceptions of their wellbeing in school is outlined. Data are presented from a survey of 5170 students from 20 primary and 20 secondary schools across England that identify four dimensions of wellbeing. Differences in self-reported wellbeing relating to age, gender and type of school attended (Creative Partnerships versus other schools) are explored. The implications of these findings, particularly differences related to type of school attended given the focus of this special edition, are considered.This is the author accepted manuscript. The final version is available from Taylor & Francis via http://dx.doi.org/10.1080/0305764X.2014.88965
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