基于损伤退化模型的钢筋混凝土梁式桥加固计算方法研究

为了客观反映材料退化、结构损伤、运营环境变化及结构工作状态改变等因素对桥梁承载能力的影响,分析了桥梁加固计算的特点,给出了基于损伤退化模型的钢筋混凝土梁式桥正截面及斜截面承载能力计算公式,提出了结构加固计算的一般步骤,并以工程实例给出了具体应用方法。     

东风汽车公司商用车发动机的研发历程

介绍了东风汽车公司几款有代表性商用车发动机的研发过程,阐述了东风汽车公司在发动机研发领域贯彻＂改进一代、开发一代、预研一代＂的方针,坚持技术创新,走自主研发与技术引进相结合,开展商用车发动机研发的历程,对我国汽车行业的发展路线有借鉴意义。     

Changes in the external costs of freight surface transport In Spain

This paper studies the external costs of surface freight transport in Spain and finds that a reduction occurred over the past15 years. The analysis yields two conclusions: trucks have experienced a reduction in external costs, and rail has lower externalities. The external costs of road freight transport decrease between 1993 and 2007 (44%). The external costs of rail freight increase by 12%. During this period, the external costs of road freight related to climate increase by 16%, oppositely than those from air pollution and accidents (51 and 44%). The external costs of rail related to pollutant emissions and climate increase by 4% and 43%. Oppositely, the external costs related to accidents decrease by 27%. Road freight generates eight times the external costs of rail, 2.35 Euro cents per tonne kilometre in 2005 (5.6% accidents, 74.7% air pollution and 19.7% climate) vs. 0.28 (13.4% accidents, 53.9% air pollution and 32.7% climate).     

基于THS1206的电能质量数据采集实现

电能质量数据采集系统主要包括：主控电路、互感器电路、信号采集与调理电路及人机交互电路.本文主要介绍其中的信号采集与调理电路,由于信号采集电路中谐波电压值相对标准电压值较小,同时为了保证可以准确采样到高次谐波信号,用到的A/D不仅要求采样精度较高且转换速度要快.本文选用了TI公司生产的型号为THS1206的12位4通道高速A/D,这样既满足了电能质量检测中的数据精度要求,同时也满足了测量速度的要求.     

A11公路拓宽改建工程SMA沥青路面质量控制研讨

该文通过介绍A11沪宁高速公路拓宽改建工程SMA沥青路面的施工工艺,结合现有规范标准和A11高速公路SMA施工质量标准,总结了SMA沥青混合料在高速公路改建工程中的质量控制方法,确保了A11拓宽改建工程SMA沥青面层的施工质量。     

专线 4245A道岔在运营中的常见病害及整治措施

遂成高铁在大英东、积金南、准口南站,正线通过的岔道,均采用专线4245A型道岔。营运3年以来发生了路基沉降、线位偏移、轨道框架失稳等病害。针对客专道岔（专线4245A）在遂成线运营中的常见病害进行分析,提出了遂成线道岔精调及病害整治的具体措施。     

基于B．P．R模型的综合交通枢纽客运换乘量预测

在对比研究各种换乘量预测模型的基础上,针对其流量分布与交通规划“四阶段法”中的交通分布预测在原理及结果表达方面的相似之处,引入B,P．R模型,并结合层次分析法,弥补重力模型在标定阻抗函数方面的一些不足。将二者结合运用到对东直门交通枢纽的研究中,收到良好效果,能够比较准确地对枢纽内各种交通方式的换乘量进行预测。     

基于TLC7135的数字电压表设计

数字电压表由各种单片A／D转换器构成,精度是表征数字电压表性能的最基本参量。以单片机为核心,辅以4位半表头芯片TLC7135,设计一个4位半精度的精密数字电压表,该数字电压表具有结构简单、编程简洁、占用单片机资源少等优点,在测量领域具有一定的应用价值。     

Productive efficiency of public and private solid waste logistics and its implications for waste management policy

This paper measures the productive efficiency of municipal solid waste (MSW) logistics by applying data envelopment analysis (DEA) to cross-sectional data of prefectures in Japan. Either through public operations or by outsourcing to private waste collection operators, prefectural governments possess the fundamental authority over waste processing operations in Japan. Therefore, we estimate a multi-input multi-output production efficiency at the prefectural level via DEA, employing several different model settings. Our data classify the MSW into household solid waste (HSW) and business solid waste (BSW) collected by both private and public operators as separate outputs, while the numbers of trucks and workers used by private and public operators are used as inputs. The results consistently show that geographical characteristics, such as the number of inhabited remote islands, are relatively more dominant factors for determining inefficiency. While the implication that a minimum efficient scale is not achieved in these small islands is in line with the literature suggesting that waste logistics has increasing returns at the municipal level, our results indicate that waste collection efficiency in Japan is well described by CRS technology at the prefectural level. The results also show that prefectures with higher private-sector participation, measured in terms of HSW collection, are more efficient, whereas a higher private–labor ratio negatively affects efficiency. We also provide evidence that prefectures with inefficient MSW logistics have a higher tendency of suffering from the illegal dumping of industrial waste.     

ZPW-2000A三接近区段存在的问题及解决方案

就ZPW-2000A自动闭塞系统电路三接近区段存在的问题进行了具体分析，提出解决问题的方法，确保行车效率和行车安全。