Review of Life-Cycle Assessment Applications in Building Construction

Life-cycle assessment (LCA) has been used to assess product development processes “from cradle to grave” for many years. With the current push toward sustainable construction, LCA has gained importance as an objective method to evaluate the environmental impact of construction practices. A substantial amount of construction-related LCA work has been published recently; however, most of this work has been fragmented and a systematic compilation of this literature has not been undertaken. This article presents a structured review of building construction-related LCA literature, classified under four categories: LCA applications for construction products selection; LCA applications for construction systems/process evaluation; LCA tools and databases related to the construction industry; and LCA methodological developments related to the construction industry. Current challenges for using LCA in construction are discussed and potential areas for future research are highlighted. This review and similar efforts may provide the construction industry and associated researchers the necessary background to make better-informed construction decisions and assist the development of an agenda for further research.     

Identifying Shared Environmental Contributions to Early Substance Use: The Respective Roles of Peers and Parents.

Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c2 = .51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of practice tests in the accuracy of test predictions on text material.

Investigated the role of practice tests in predictions about test performance on texts. Generally, Ss predicted their relative performance on tests accurately. However, answering practice-test questions that were drawn from the same pool as criterion-test questions did not improve prediction accuracy. The main reason for this was that practice-test scores for specific texts did not correlate with criterion-test scores. In addition, neither practice tests that were identical to the criterion tests nor practice tests consisting of the question stems improved the accuracy of test predictions relative to no-practice tests. With identical practice and criterion tests, accuracy of self-generated feedback correlated positively with the accuracy of test predictions. For similar practice and criterion tests, however, accurate experimenter-provided feedback reduced test-prediction accuracy, presumably because of the lack of reliability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential sensitivity of Japanese macaques (Macaca fuscata) and humans (Homo sapiens) to peak position along a synthetic coo call continuum.

Difference limens (DLs) for changes in the temporal position of a pitch peak along a synthetic early-high to late-high coo continuum were measured in 2 Japanese macaques and 2 humans in a low-uncertainty, repeating standard discrimination procedure. Lowest DLs (19–32 msec for monkeys;     

便携式电子产品的散热管理

减小封装尺寸和提高性能的双重要求向便携式系统设计工程师提出了解决散热管理问题的严峻挑战.提高性能通常通过提高时钟频率和提高集成度来实现,但是这两种做法都会引起功耗增加.另外封装尺寸减小势必增加了器件的散热困难.因此,便携式设备的散热问题因受重量、通风配置、防风雨和其它因素的限制而进一步加重.     

Profiling under UNIX by patching

Profiling under UNIX is done by inserting counters into programs either before compiling, during compiling or during assembly. A fourth type of profiling involves monitoring the execution of a program, and gathering relevant statistics during the run. This paper looks at this method and an implementation of it, and discusses its advantages and disadvantages.     

Prospective/intentional and incidental everyday memory: Effects of age and passage of time.

Investigated the effects of age and passage of time on incidental and prospective/intentional everyday memory. 79 23–93 yr old volunteers were tested twice, and 33 of the Ss were tested 3 times over an 18-mo period. They were asked to recognize or recall, either in writing or orally, experiences from a 3-day period in which they served as research Ss. Results demonstrate that incidental, but not prospective/intentional, memory appeared to be influenced by age and passage of time. Results imply that salience and context are important factors in aging memory performance and that certain types of everyday retrospective reports may be reliable. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

透视Virtex-4超高效且低功耗的奥秘

随着工艺技术越来越小型化、越来越快速,通常会增加功耗,这时在功耗和效能上往往必须有所取舍,因而器件功耗一直是半导体业的首要课题。来自Xilinx的新型Virtex-4FPGA采用创新的架构特性和先进的IC设计技术,可以在显著降低功耗的同时,依然不损害其性能,且和90nm工艺技术特征尺寸减小的趋势不谋而合。本文将探讨XilinxIC设计者如何在高性能Virtex-4FPGA中实现很高的功率效率。     

采用多层式结构的Raychem快速动作表面贴装熔断器

Raychem快速动作表面贴装熔断器是一种应用广泛的新型元件。该熔断器可为使用低于63V直流电源的系统提供过流保护，并有助于开发更可靠的高性能电子产品。目前已应用于手提电脑、多媒体装置。手机等便携式电子产品。