租房保险发展缓慢的原因及其对策分析

为了保障租房者的利益,2004年我国推行了租房保险,但是,租房保险市场占有量一直很低,本文主要是对租房保险发展缓慢的原因做了探讨并进一步给出了针对性的可行性建议。     

停车管理信息系统的需求分析与功能设计

随着小汽车进入家庭，城市机动化水平的进一步提高，停车难的问题越来越严重。在中国的一些大城市中如北京、上海、广州等，特别是在高峰时段，一方面有大量汽车在拥挤的道路上寻找停车车位；另一方面有部分停车场却因为诸多原因利用率很低，这样造成了：     

车辆荷载测量系统的对比试验研究

运动中的车辆荷载测量系统（Ｗｅｉｇｈ－ｉｎ－Ｍｏｔｉｏｎ ＷＩＮ）是安装于路面之中或路面表面，用于测量行驶中车辆的轴载等数据的系统。本文给出几种不同ＷＩＭ系统的对比试验研究结果。对于选择可靠的ＷＩＭ系统具不重要的参考价值。     

客运专线制梁场的环境影响分析及对策的探讨

随着客运专线沿线桥梁预制场的大量设置,其生产活动引起的环境影响已得到了广泛关注。本文根据近年来对部分客运专线实施环境监控和竣工环保验收的实践经验,充分客观的分析了制梁场的建设、生产过程中产生的主要环境问题,并提出了切实可行、具有针对性的保护措施建议。     

GAC—16沥青混合料在赣西干线公路中的应用研究

依托赣西干线公路路面质量提升技术应用研究项目,从地区矿料组成入手,提出了GAC配合比设计方法,并与常规的AC-16进行对比。室内试验结果表明:GAC-16残留稳定度为90.1%,劈裂强度比81.4%,动稳定度为10 328次/mm,破坏应变为2 734.5με。由此可知GAC-16沥青混合料在高温稳定性方面具有一定的优势,在水稳定性和低温性能方面略有改善。其应用效果可为该地区后续工程提供技术参考,具有一定的推广价值。     

追求精细化的街道设计——《伦敦街道设计导则》解读

自20世纪90年代,英国的交通政策就在向整合交通和土地利用规划的方向努力。伦敦交通局于2004年发布了《伦敦街道设计导则》(以下简称《导则》),并于2009年修订。该导则作为"更好的街道"计划的一部分,对伦敦市区的街道项目具有重要的引导作用。首先通过叙述伦敦市街道形态与规划政策的演变,介绍《导则》的政策背景、概要内容及设计原则。从设计流程、材料面板、街道设计指引几个方面解析《导则》的特点。通过研究伦敦市的道路形态和街道设计现状,评述《导则》的落实与应用情况。最后,从全过程精细化指导、规范标准补充、街道设计理念转变三个方面总结《导则》对中国城市街道设计的借鉴意义。     

Histologic changes in the sinus membrane after maxillary sinus augmentation with simultaneous implant placement using engineered bone graft material

The aim of the study was to analyze the histologic and ultrastructural changes after maxillary sinus augmentation with simultaneous implant placement using engineered bone graft material. In this study, calcium phosphate cement (CPC) scaffolds combined with goat bone marrow stromal cells (BMSCs) were used to fill goat sinus floor space after maxillary sinus floor elevation with simultaneous implant placement comparing with those not filled any grafted materials and used as controls. After a healing period of 3 months, the goat maxillary sinus membrane was examined using light microscopy and scanning electronic microscopy. The results showed that the connective tissue thickness and the epithelium thickness of mucosa were not statistically significant difference between two groups. The tissue engineered bone complex might be an ideal graft for the sinus floor elevation and have no influence on the sinus membrane under the histological and ultrastructural observation.     

轴承滚子表面三维形貌模拟

建立了油石超精加工的运动模型和切削模型，对滚子表面形貌进行三维仿真模拟，用VB语言编程驱动AutoCAD2000将各参数改变时工件表面形貌进行计算机仿真．用VB语言编程驱动Excel绘图直观地表示出工件转动的圆周线速度、油石振动频率、油石振动振幅、油石切削量等参数变化对工件外圆表面形貌和油石超精性能的影响．通过计算机仿真为油石超精加工技术提供了理论依据，拓展了油石超精加工技术的应用前景．     

Characteristics of Trihalomethanes in Water Distribution System

To investigate the characteristics of disinfection by-products (DBPs) in an actual water distribution system using the raw water with high bromide ion concentration, the composition and concentration of trihalomethanes (THMs) formed by chlorination of the water in the presence of bromide ion were measured in a city water distribution system during one year. The results show that brominated THMs contributed a great part (83%-89%) to the index for additive toxicity (ATI) and resulted in the ATI of most of the samples exceeding WHO guideline standard for total THMs (TTHMs), especially during the summer (rainy season). This indicates that the chlorination of water in the presence of bromide ion leaded to high ratios of brominated THMs to TTHMs. However, a visible increase in the concentration of THMs with increasing residence time in the distribution system was not observed. Additionally, based on alternatives analysis, packed tower aeration method is proposed to reduce THMs level of the finished water leaving the treatment plant.