A criterion for atomicity revisited

Concurrent and reactive programs are specified by their behaviours in the presence of a nondeterministic environment. In a natural way, this gives a specification (ARW) of an atomic variable in the style of Abadi and Lamport. Several implementations of atomic variables by lower level primitives are known. A few years ago, we formulated a criterion to prove the correctness of such implementations. The proof of correctness of the criterion itself was based on Lynch’s definition of atomicity by serialization points. Here, this criterion is reformulated as a specification HRW in the formal sense. Simulations from HRW to ARW and vice versa are constructed. These now serve as a constructive proof of correctness of the criterion. Eternity variables are used in the simulation from HRW to ARW. We propose so-called gliding simulations to deal with the problems that appear when occasionally the concrete implementation needs fewer steps than the abstract specification.     

强夯法处理大块填石地基的应用实践

对用大块填石的地基，通过试验，采用合适能量的夯锤进行强夯处理，改变地基结构排列、使其致密，从而提高地基承载力，是一种经济有效的地基处理方法。     

内复合换热管与复合管板焊接工艺试验研究

介绍复合管与复合管板的管头设计及其焊接试验,结果表明,如果管内壁不锈钢复合层的厚度达到或大于0.5mm,则管头的焊接质量能满足要求,否则管头焊缝容易开裂。内、外双面复合管和复合管板的管头焊接工艺,与仅有内壁单层不锈钢复合层的复合管和复合管板的管头焊接工艺相同。     

德国玩具店时兴简约质朴

您的店铺里有一面砖墙，或地毯底下是砖石地面？那么，您应该为此感到高兴了。因为2006年德国玩具零售店的装饰正趋向反璞归真。 店铺里至少留出一面砖墙不施加任何粉刷，砖石地面裸露。这样，可以迎合玩具零售顾客对真实感的需求。在具有这种装饰风格的商店里，人们感觉一切都是非常自然、真实的。[编者按]     

高坝风险分析的事件树法

新世纪一批高坝将要在我国开工建设,这对我国的水电能源及国民经济的发展有着不可估量的作用,而高坝建设中,安全性是需要首先保证的。目前对高坝的风险分析方法有主观概率法、客观概率法等。从系统工程的角度出发,采用事件树方法对高坝的风险进行了探索研究,并给出了算例以说明该方法的有效性和实用性。     

胃动力信息采集与分析系统设计

本文设计了一套提取胃电和胃阻抗信号的胃动力信息采集与分析系统，该系统由采集系统和分析系统两部分构成。前者以单片机（ADuC834）为核心部件，实现了胃电和生物阻抗信号的同步采集和数据传输。后者对提取的阻抗信号和胃电信号运用小波多分辨分析处理，利用小波变换将胃阻抗信号从呼吸和血流信号中分离。系统可以应用于分析功能性消化不良患者胃动力的电过程和机械过程。     

En/Decoder for Spectral Phase-Coded OCDMA System Based on Amplitude Sampled FBG

A novel en/decoder for spectral phase-coded optical code-division multiple-access system based on amplitude sampled fiber Bragg grating (FBG) is proposed. Both equivalent chirp and equivalent phase shift are achieved by amplitude sampling. Compared with previous en/decoder based on step chirped FBG, it is easier to fabricate. The performance of the proposed en/decoder is verified by both numerical simulation and experimental demonstration.     

Geotechnical properties of the soft soil in Guangzhou College City

The paper describes some geotechnical properties of the soft soils in Guangzhou College City, China, which are difficult to both sample and test. Laboratory and in situ tests were carried out to assess the physical and mechanical indices of the soils. The data were statistically analyzed and linear regression undertaken such that equations could be developed by which the geotechnical properties of the soft soils can be predicted. The statistical validity of the degree of correlation confirmed that using these equations, the mechanical indices can be estimated from physical indices determined by routine testing.      

提高工程量清单编制质量的思考

文章从如何提高对工程量清单编制工作重要性的认识入手,分析了实现计价理念、计价侧重点和造价控制观念转变的必要性,重点阐述了提高工程量清单编制质量应给予足够重视的几个关键环节。