数学公式结构控制与显示研究

由于受到HTML本身特点的限制,在web上显示非平直文本的效果不佳.本文针对数学公式的结构特点,通过对各种结构的分析,使用JavaScript语言编写一套结构库.利用结构库中的各种结构控制函数,从而实现数学公式的各种结构在web中的显示.     

基于单目视觉的结构化道路检测算法研究

为了全面了解基于单目视觉的结构化道路检测方法的现状,给出近些年来一些典型的道路检测算法,并进行分类,包括基于灰度特征和彩色特征的检测算法、基于模型的识别算法,最后对该领域的难点和趋势给出简要的论述。     

《数据结构》精品课程建设实践探讨

从教师队伍建设、教学模式和实验模式等方面总结《数据结构》精品课程的建设与实践过程,采用教学科研相结合的模式进行教师队伍的建设。通过采用基于构建主义的课堂教学模式、模拟项目驱动的实验教学模式和基于多媒体技术的综合教学模式,使学生学习变被动为主动。多种教学模式的结合改变了传统的教学模式和实验模式,在整个教学过程中,充分体现了学生的主体地位和教师的主导作用,从而培养了学生解决问题、分析问题和创新能力。     

MACROMOLECULAR STRUCTURE OF COALS. I. THE ORGANIC PHASE OF BITUMINOUS COALS AS A MACROMOLECULAR NETWORK†

The organic phase of bituminous coals may be represented as a three-dimensional macromolecular network, with chains consisting of aromatic or heterocyclic clusters and smaller connecting bonds, usually of etheric, sulfidicor methylenic nature. The crosslinks are covalently bonded bridges or hydrogen-bonded structures. The molecular weight between crosslinks, [Mbar]_C, and other parameters of the crosslinked structure can be calculated using the results of various experiments and applying theories widely used for the analysis of polymeric networks, albeit with significant modifications.     

Comparative life cycle costs for new steel portal frame building systems

Life cycle costs of a new steel portal frame building system incorporating energy efficient sandwich panels are compared with those of a conventional steel portal frame building system for use in industrial and commercial buildings. The economic benefits of the new building system have been demonstrated through cost assessment of energy in use. The results from life cycle cost analysis of both the new and conventional portal frame building systems indicate that, despite slightly higher initial costs, the new building system costs significantly less than the conventional system over its complete life cycle of 50 years. The new system provides improved economic performance along with a more energy-efficient model for commercial/industrial building design in the Australian climate. Le coût du cycle de vie d'un nouveau système de bâtiment à portique en acier comportant des panneaux en sandwich efficaces au plan énergétique est comparé à un système classique pour un emploi dans des bâtiments industriels et commerciaux. Les avantages économiques du nouveau système ont été démontrés par une évaluation des dépenses énergétiques. Il ressort de l'analyse comparative du coût du cycle de vie du nouveau et de l'ancien système qu'en dépit d'une légère augmentation du coût de départ, le nouveau système est nettement moins onéreux que l'ancien sur un cycle de vie complet de 50 ans. Les performances économiques du nouveau système sont supérieures à celles du système classique, avec de meilleures performances énergétiques pour la conception de bâtiments commerciaux et industriels sous le climat australien.     

结构专业施工图审查心得

通过结构专业施工图审查工作,对玻璃幕墙设计和相邻建筑干扰对风压体型系数的影响等方面,作了深入探讨,偶有所得。本文就此作了论述,供同行讨论、交流。     

深化应用WBS架构促进配网项目标准化管理实践

为更好地实现SG-ERP建设目标,促进配网标准化管理,无锡供电公司在深化应用江苏电力配网标准WBS架构的进程中,不断探索实践,以项目立项、设计、实施、竣工投运、转资、项目关闭和六大关键环节管控为重点,以系统限制和信息化考核为手段建立双重保障,有力地促进了无锡配网项目标准化管理和全过程监督管控能力。     

Impact of experimental conditions on material response during forming of steel in semi-solid state

Semi-solid forming is an effective near-net-shape forming process to produce components with complex geometry and in fewer forming steps. It benefits from the complex thixotropic behaviour of semi-solids. However, the consequences of such behaviour on the flow during thixoforming, is still neither completely characterized and nor fully understood, especially for high melting point alloys. The study described in this paper investigates thixoextrusion for C38 low carbon steel material using dies at temperatures much lower than the slug temperature. Four different process parameters were studied: the initial slug temperature, the die temperature, the ram speed and the presence of a ceramic layer at the tool/material interface. The extruded parts were found to have an exact shape and a good surface state only if the temperature was below a certain value. This critical temperature is not an intrinsic material property since its value depends on die temperature and the presence of the Ceraspray© layer. Two kinds of flow were highlighted: a homogeneous flow controlled by the behaviour of the solid skeleton characterized by a positive strain rate sensitivity, and a non homogeneous flow (macro liquid/solid phase separation) dominated by the flow of the free liquid. With decreasing ram speed, heat losses increase so that the overall consistency of the material improves, leading to apparent negative strain rate sensitivity. Finally, some ways to optimise thixoforming are proposed.     

Effect of steel fiber hybridization on the fracture behavior of self-consolidating concretes

In the present work the effect of steel fiber hybridization on the mechanical and rheological behavior of self-consolidating concretes was studied. Straight and hooked end steel fibers with different lengths and diameters were used as reinforcement in fiber volume fractions of 1.0% and 1.5%. The viscosity and shear yield stress of the concretes was determined using a parallel plate rheometer. The mechanical behavior was determined by means of compression, tension and bending tests. The movement of the neutral axis under bending load was experimentally determined by strain-gages attached to compression and tensile surfaces. The mechanical response of the material under bi-axial bending was addressed using the round panel test in three different boundary conditions. The obtained results indicated that the fiber hybridization improved the behavior of the composites for low strain and displacement levels increasing the serviceability limit state of the same through the control of the crack width.     

The effect of ionic liquids with imidazolium and pyridinium cations on the corrosion inhibition of mild steel in acidic environment

Ionic liquids with chemical formula 1,3-dioctadecylimidazolium bromide and N-Octadecylpyridinium bromide were synthesized by conventional and microwave-assisted reactions, respectively. Ionic liquids tested as corrosion inhibitors after polarization curves displayed corrosion protection efficiency within 82-88% at 100 ppm for mild steel in a 1 M aqueous solution of sulfuric acid. Standard free energy indicated that corrosion inhibition occurred by a chemical adsorption process. Surface analysis (SEM, EDX) completed by XRD and Mössbauer spectroscopy indicated the presence of carbon species pertaining to inhibitor and corrosion products, which was rationalized in an inhibition mechanism.