天津独流减河工程监控系统现地通信单元设计

提出一种配电网电容电流测量的新方法，在零序电压互感器的开口三角侧串联一个可调电感，通过注入一个变频恒流信号寻找配电网的谐振频率，改变可调电感的数值后寻找另一谐振频率，联立2个谐振方程求解电容电流，该方法消除了电压互感器漏抗对测量的影响。开发了配电网电容电流测量仪，经模拟试验和现场测试表明，该方法具有安全、快捷、准确等特点，适用于中性点不接地或经随调式消弧线圈接地配电网。     

关于征地制度的思考

针对当前农村土地问题的现状．认为调整农村土地关系改革土地制度是解决当前农村问题的关键之一。介绍苏格兰土地改革的经验．提出农村土地转为非农用地的交易中国家应实行限制性措施．可尝试建立“国家失地农民账户”和“国家失地农民保障基金”．从而合理分配土地交易产生的级差收益保障失地农民的合法利益。     

Forgotten pioneers of color order. Part I: Gaspard Grégoire (1751–1846)

Some 100 years before Albert Munsell developed his color order system, French silk merchant and inventor of a technology for producing works of art in silk velours, Gaspard Grégoire, introduced a color order system based on the color attributes hue, (relative) chroma, and lightness. Conceived in the mid‐1780s, an atlas with 1350 samples was produced before 1813 and found use in French Royal manufacturing operations and educational institutions. It was followed a few years later by one with 343 samples. Grégoire's work was subsequently overshadowed by Michel‐Eugene Chevreul's more complicated and less intuitive hemispherical system of 1839. © 2007 Wiley Periodicals, Inc. Col Res Appl, 33, 5–9, 2008     

Breakdown of oil films and formation of residual films

The breakdown processes of oil films under quasi-static loading have been investigated by using a newly developed steel-oil-mercury system. The relationship between the thickness and breakdown ratio of a hexadecane film is represented by a single master curve independently of the indentation speed, indentation load, and temperature. The master curve shows that the breakdown process of hexadecane includes two stages; one is the decrement of the thickness without breakdown and the other is the decrement of the thickness with a drastic progress of breakdown. By solving a small amount of fatty acid in hexadecane, the thickness increases and the breakdown ratio decreases noticeably; a multilayer residual film supporting normal load is formed between two metal surfaces. Experiments at different temperatures reveal a negative relationship between the temperature and thickness of residual film, which indicates that the residual film is organized by physical interaction rather than chemical interaction. At least under a lower concentration, the residual film appears to consist of not only fatty acid molecules but also hexadecane molecules.     

推行岩土工程体制,降低工程造价与勘探成本

推行岩土工程体制,在确保给定的安全水平条件下达到综合造价最低的目的。     

Innovation in construction: a sociology of technology approach

An alternative approach to understanding innovation is made using two intersecting ideas. The first is that successful innovation requires consideration of the social and organizational contexts in which it is located. The complex context of construction work is characterized by inter-organizational collaboration, a project-based approach and power distributed amongst collaborating organizations. The second is that innovations can be divided into two modes: 'bounded', where the implications of innovation are restricted within a single, coherent sphere of influence, and 'unbounded', where the effects of implementation spill over beyond this. Bounded innovations are adequately explained within the construction literature. However, less discussed are unbounded innovations, where many firms' collaboration is required for successful implementation, even though many innovations can be considered unbounded within construction's inter-organizational context. It is argued that unbounded innovations require an approach to understand and facilitate the interactions both within a range of actors and between the actors and technological artefacts. The insights from a sociology of technology approach can be applied to the multiplicity of negotiations and alignments that constitute the implementation of unbounded innovation. The utility of concepts from the sociology of technology, including 'system building' and 'heterogeneous engineering', is demonstrated by applying them to an empirical study of an unbounded innovation on a major construction project (the new terminal at Heathrow Airport, London, UK). This study suggests that 'system building' contains outcomes that are not only transformations of practices, processes and systems, but also the potential transformation of technologies themselves.     

射频识别模块SMC51489在门禁系统中的应用

射频识别系统一般由三部分组成:电子标签(射频卡)、读取器和天线.正确快速的识别电子标签的标签号码,是门禁系统发挥其功能的先决条件.以无源低频射频卡识别模块SMC51489为例,介绍了对射频卡信息读取的原理和方法,并给出了相应的软件编程.实验证明该模块不仅具有较大的读卡距离,而且工作可靠.     

Average consensus in networks of dynamic agents with switching topologies and multiple time-varying delays

In this paper, we discuss average consensus problem in undirected networks of dynamic agents with fixed and switching topologies as well as multiple time-varying communication delays. By employing a linear matrix inequality method, we prove that all the nodes in the network achieve average consensus asymptotically for appropriate communication delays if the network topology is connected. Particularly, several feasible linear matrix inequalities are established to determine the maximal allowable upper bound of time-varying communication delays. Numerical examples are given to demonstrate the effectiveness and the sharpness of the theoretical results.     

Optimal and self‐tuning fusion Kalman filters for discrete‐time stochastic singular systems

Based on the optimal fusion estimation algorithm weighted by scalars in the linear minimum variance sense, a distributed optimal fusion Kalman filter weighted by scalars is presented for discrete‐time stochastic singular systems with multiple sensors and correlated noises. A cross‐covariance matrix of filtering errors between any two sensors is derived. When the noise statistical information is unknown, a distributed identification approach is presented based on correlation functions and the weighted average method. Further, a distributed self‐tuning fusion filter is given, which includes two stage fusions where the first‐stage fusion is used to identify the noise covariance and the second‐stage fusion is used to obtain the fusion state filter. A simulation verifies the effectiveness of the proposed algorithm. Copyright © 2008 John Wiley & Sons, Ltd.     

从关联分析法看如何改善沥青抗老化性能

用灰色关联分析法研究了沥青抗老化性能与沥青化学组成之间的关联程度，结果表明，影响再生沥青性质的主要因素是沥青中的芳烃和胶质的含量。通过添加芳香组分能改善沥青四组分之间的配伍性，从而可以改善再生沥青的抗老化性能。并通过对再生剂进行富芳处理，验证了上述结论。