Application of Support Vector Machines in Assessing Conceptual Cost Estimates

Total conceptual cost estimates and the assessment of the quality of these estimates are critical in the early stages of a building construction project. In this study, the support vector machine (SVM) model for assessing the quality of conceptual cost estimates is proposed, and the application of SVM in construction areas is investigated. The results show that the SVM model assessed the quality of conceptual cost estimates slightly more accurately than the discriminant analysis model. This shows that using the SVM has potential in construction areas. In addition, the SVM model can assist clients in their evaluation of the quality of the estimated cost and the probability of exceeding the target cost, and in their decision on whether or not it is necessary to seek a more accurate estimate in the early stages of a project.     

钻井液固相化学清洁剂ZSC-201的合成及性能

介绍了钻井液用固相化学清洁剂ZSC－201的室内合成及性能评价，结果表明，固相化学清洁剂ZSC－201具有较强的抑制性，可有效抑制粘土水化分散，保证钻井液清洁，在钻井液体系中与阴、阳离子型钻井液处理剂配伍性好，同时具有较好的抑制增效作用，在有效的加量内对钻井液滤矢量和流变性等影响小，固相化学清洁剂ZSC－201已在中原油田近30口井中应用，具有良好的推广应用前景。     

Resource contention in shared-memory multiprocessors: A parameterized performance degradation model

A standard metric conventionally employed to compare the performance of different multiprocessor systems is speedup. Although providing a measure of the improvement in execution speed achievable on a system, this metric does not yield any insight into the factors responsible for limiting the potential improvement in speed. This paper studies the performance degradation in shared-memory multiprocessors as a result of contention for shared-memory resources. A replicate workload framework with a flexible mechanism for workload specification is proposed for measuring performance. Two normalized performance metrics—efficiency and overhead factor—are introduced to quantify the factors limiting performance and facilitate comparison across architectures. Finally, the proposed model is employed to measure and compare the performance of three contemporary shared-memory systems, with special emphasis on the newly released BBN Butterfly-II (TC2000), currently undergoing Beta test.     

一种性能可调的新型节能材料－电致变色膜

本文介绍了一种性能可调的新型节能材料—电致色薄膜，描述了以其为核心的全固态灵巧窗结构、工作原理和光学调节性能，回顾了电致色材料、离子存储层和固态锂离子导体及其性质，并展望了这种新型节能材料的应用。     

Control of calcium hexaluminate grain morphology in in-situ toughened ceramic composites

The influence of processing conditions on the morphology of calcium hexaluminate (CA₆) grains in Al₂O₃: 30 vol% CaO·6Al₂O₃ (CA₆) ceramic composites was investigated. Specimens were prepared by in-situ reaction sintering using precursor powders of alumina, and either calcium carbonate or calcium oxide. In some samples, 1 vol% anorthite glass was added as a sintering aid. X-ray diffraction was used to study the phase development in the as-calcined and sintered states. The resultant microstructures were characterized using both scanning electron microscopy (SEM), and imaging secondary ion mass spectrometry (SIMS). It was found that the CA₆ grains developed a platelike morphology when CaCO₃ was used as the starting calcium-rich powder. In contrast, samples prepared using CaO resulted in equiaxed CA₆ grains. This result was observed to be independent of the anorthite glass addition. The findings are rationalized in terms of distinct CA₆ reaction mechanisms, resulting from differences in the reactivity of the powders during the early stages of calcining.Cement Nomenclature C CaO - A Al₂O₃     

混酸PEG酯的合成及性能研究

用从大豆油脚水解制得的脂肪酸合成混酸聚乙二醇酯，通过测定酸值的方法确定了最佳反应时间为16h。与油酸聚乙二醇酯相比，混酸聚乙二醇酯具有更优良的乳化性、润湿性，可以替代油酸聚乙二醇酯用于纺织、农药和化妆品工业中。     

铸铁热分析用试样新型激冷剂的实验研究

从冷却曲线上相变段倾角最小原则出发，研究了新型激冷剂的配比与热分析法检测铸铁成分精度的关系，实验结果表明，能使相变段倾角最小的成分配比，也能提高对铸铁成分的热分析和检测精度。     

Implementation of secure digital communication by hyperchaoticsynchronisation

By active-passive-decomposition synchronisation, the application of the one-way coupled ring map lattice hyperchaotic system in secure digital speech communication is demonstrated. Synchronisation guarantees strong security and recovery without error     

片状陶瓷材料高低温电性能参数的自动检测

由进口电性能仪配上自制的高温系统，计算机自动采集数据，配置成一套高低温电性参数测定装置，该装置的特点是，升温快，炉体小巧，炉芯可更换盛液氮装置，屏蔽良好，等温区长，温工及参数测量精确可靠。