Perceived Air Quality,Sick Building Syndrome (SBS) Symptoms and Productivity in an Office with Two Different Pollution Loads

Abstract Perceived air quality, Sick Building Syndrome (SBS) symptoms and productivity were studied in an existing office in which the air pollution level could be modified by introducing or removing a pollution source. This reversible intervention allowed the space to be classified as either non-low-polluting or low-polluting, as specified in the new European design criteria for the indoor environment CEN CR 1752 (1998). The pollution source was a 20-year-old used carpet which was introduced on a rack behind a screen so that it was invisible to the occupants. Five groups of six female subjects each were exposed to the conditions in the office twice, once with the pollution source present and once with the pollution source absent, each exposure being 265 min in the afternoon, one group at a time. They assessed the perceived air quality and SBS symptoms while performing simulated office work. The subject-rated acceptability of the perceived air quality in the office corresponded to 22% dissatisfied when the pollution source was present, and to 15% dissatisfied when the pollution source was absent. In the former condition there was a significantly increased prevalence of headaches (P= 0.04) and significantly lower levels of reported effort (P=0.02) during the text typing and calculation tasks, both of which required a sustained level of concentration. In the text typing task, subjects worked significantly more slowly when the pollution source was present in the office (P=0.003), typing 6.5% less text than when the pollution source was absent from the office. Reducing the pollution load on indoor air proved to be an effective means of improving the comfort, health and productivity of building occupants.     

Preparation of SrBi 2 Ta 2 O 9 Thin Films by Liquid-Delivery MOCVD Without Additional Solvents

SrBi 2 Ta 2 O 9 thin films were prepared by ECR plasma enhanced metalorganic chemical vapor deposition (ECR-MOCVD) with a liquid-delivery system using one cocktail source without an additional solvent. The strontium-tantalum double alkoxide, Sr{Ta[OC 2 H 4 H(CH 3 ) 2 ](OC 2 H 5 ) 5 } 2 , was dissolved in stabilized trimethyl bismuth, Bi(CH 3 ) 3 / dioxane. This source system has been used in a conventional bubbling system. Deposition rate and the composition of the films were strictly controlled by the concentration and the composition of the cocktail source. Therefore, high reproducibility was realized by using this system. The constituent phase of the stoichiometric SBT film as-deposited at 500 C on a (111)Pt/TiO 2 /SiO 2 /Si substrate was a fluorite phase and transformed to the single phase of SBT by the post annealing at 800 C. It showed almost the same ferroelectricity as the stoichiometric composition film.     

基于单片机控制的电镀层厚度记录仪设计

电镀层厚度是电镀工艺的重要指标,其与电镀金属材料、电镀电流强度、电镀时间等有关。本文设计的基于单片机的电镀层厚度记录仪,能准确的记录给定电镀金属材料和恒定电流强度的电镀层金属厚度。讨论电镀层厚度形成因素和记录方法,给出系统硬件设计方案和软件流程图。     

Microsoft,Open Source and the software ecosystem: of predators and prey—the leopard can change its spots

Over the past few years, Microsoft has promoted a project called ‘Shared Source Initiative’, which allows certain customers (e.g., research institutions and independent software vendors) access to its source code on a restricted basis. As part of this initiative, Microsoft introduced some licences that appear to give unrestricted access to source code and closely resemble ‘traditional’ Open Source licences. In July 2007, two of these ‘shared source’ licenses (the Microsoft Community Licence and the Microsoft Permissive Licence) were submitted to the Open Source Initiative (OSI) and subsequently approved by the OSI as certified Open Source licences. Thus Microsoft's Shared Source Initiative and its partial embrace of Open Source appear to be a significant step towards closing the ideological rift between developers of proprietary software and the Free/Open Source software movement, and more than just another attempt to appease consumers and/or critics in terms of software transparency. By analysing the ‘evolution’ of Microsoft's Shared Source licences, this article aims to shed some light on the question what is needed for a ‘predator’ (i.e., proprietary, software developer) such as Microsoft to become ‘prey’ (i.e., be part of the Open Source community). This article concludes that, although Microsoft's efforts are to be lauded, it is highly unlikely that the company will embrace fully the Open Source philosophy in the near future.     

光电光谱仪及其应用

光电光谱仪具有分析速度快、准确度高、可以同时测定若干元素以及操作简便等优点，广泛应用于机械、冶金等行业的金属材料化学成分分析。本文主要介绍了光电光谱仪的测量原理、基本结构及其在生产实际中的应用。     

用卡诺图设计Ⅴ╱Ⅶ编码器和Ⅶ╱Ⅴ译码器

介绍用多变量卡诺图设计Ⅴ/Ⅶ编码器和Ⅶ/Ⅴ译码器的方法。特点是直观、简便、易于掌握。阐述了Ⅴ/Ⅶ编码器和Ⅶ/Ⅴ译码器在数据传输系统中的应用以及用多变量卡诺图进行设计的具体步骤和方法,并提供了具体的逻辑电路图。     

数字光信号源：—光纤通信系统的一种新型配套仪器

本文叙述了数字光信号源的主要用途、性能参数、工作原理和电路设计原理及原理图。     

A large-time-stepping scheme for balance equations

A well-balanced, large-time-stepping method for conservation laws with source terms is presented. The numerical method is based on a local reformulation of the balance law as a conservation law with a discontinuous flux function, and the approximate solution of this equation by a front tracking method. This yields an unconditionally stable method which is particularly well suited to calculate stationary states. The viability of this approach is demonstrated by several numerical examples. KHK has been supported in part by an Outstanding Young Investigators Award from the Research Council of Norway.     

按需印书闯出一片天地

<正>按需印书(Books Print On Demand),简单地说就是书籍在需要的时候才印,不必事先印刷囤积,是“零存货”的概念。日本丰田汽车早年提出“零”装配流程,零件正好在用到的时候送来,待料的时间等于零,存货也等于零,产能因此大幅     

酒东,酒西盆地的异同与油气勘探

酒东盆地和酒西盆地都是祁连褶皱系为山前盆地，在同一区域构造应力场控制下发育，有很多相似性。酒西盆地自３０年代以来发现了一批浅层油气藏，酒东盆地多年勘探却无重大突破。分析二者的异同，认为：（１）盆地边界条件不同，导致局部应力作用方式有别，酒西盆地逆冲－褶皱变形强列，酒东盆 构造变形微弱，中浅、浅层断裂少；（２）主要是油源层都是深部下白垩统赤金堡组的成熟－－高成熟烃源岩；（３）酒西盆地的深部油气以断裂