地铁机电安装工程中的总承包管理探讨

本文通过重庆轻轨一号线沙大段机电安装总承包项目实践,探讨了地铁机电安装工程的“四多”特点,论述了机电总承包方在各专业承包商接口与施工界面管理、施工顺序管理、联合施工计划管理、材料设备及大型设备运输管理、施工质量管理、施工安全管理和合约管理等几大管理要素的内容、方法、要点。     

Drawing Time

Head of the Department of Architecture and Landscape Architecture at the University of Greenwich, Nic Clear is renowned for his role in championing film and animation techniques in architectural education. Here he challenges architects to put aside their assigned roles as mere imagers or practice technicians and embrace ‘the spatial possibilities offered by a whole range of emerging design activities - actual, augmented and virtual’.     

天水城市可持续发展指标体系及综合评价

以科学发展观为指导,从经济、社会、资源环境、基础设施和管理五个子系统方面构建天水城市可特续发展的评价指标体系。天水城市可持续发展的综合指数表明天水当前处于基本可持续发展状态。     

广义综合蓄热法混凝土蓄热冷却计算理论的简化与应用(上)

论述了广义综合蓄热法混凝土蓄热冷却计算理论的简化计算出发点、理论依据及数学推导过程，并用简化公式计算了同一状态下蓄热的防冻剂砼Ｚ－１５及ｔ－１５值，用此简化公式与理论公式比较之，以求算广义综合蓄热法理论公式与简化公式计算误差限，通过哈尔滨卷烟厂综合大楼裸露面系数Ｍ＝２５的－１０℃现浇防冻剂砼楼板实测，证明负温条件下广义吴震东公式简化计算公式可以使用。     

Inventing the Rural: A Brief History of Modern Architecture in the Countryside

The rural has long occupied a valuable, if under-theorised position in modern architectural history. Here, Cole Roskam , Assistant Professor of Architectural History at the University of Hong Kong, highlights key moments in this history and, in doing so, illuminates a central paradox at the heart of architecture's various turns to the countryside; namely, can architects maintain the physical and social integrity of the rural when they are themselves a fundamental vector of its changing character?     

Urinary BTEX, MTBE and naphthalene as biomarkers to gain environmental exposure profiles of the general population

The aim of this work was to evaluate urinary benzene, toluene, ethylbenzene, m+p-xylene, o-xylene (BTEX), methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and naphthalene (NAP) as biomarkers of exposure to environmental pollutants. Personal air and urine samples from 108 subjects belonging to the Italian general population were compared. Urinary profiles were obtained by headspace gas chromatography-mass spectrometry. BTEX, MTBE, ETBE and NAP median airborne exposures during a 5-h sampling were 4.0, 25.3, 3.8, 9.3, 3.4, 3.4, < 0.8, and 3.4 µg/m³, respectively. Meanwhile, median urinary levels, as geometric means of three determinations were: 122, 397, 74, 127, 43, 49, < 15, and 46 ng/L, respectively. Urinary benzene and toluene concentrations were 4.6- and 1.2-fold higher in smokers than in non-smokers. For most chemicals, significant positive correlations between airborne exposure (log-transformed) and the corresponding biological marker (log-transformed) were found, with Pearson's r values for correlation, ranging from 0.228 to 0.396. Multiple linear regression analysis showed that the urinary level of these chemicals was influenced by personal airborne exposure, urinary creatinine, and urinary cotinine, with R² 0.733 for benzene. Urinary chemicals are useful biomarkers of environmental exposure. Given the ease of rapidly obtaining urine samples, they represent a non-invasive alternative to blood chemical analysis. The possibility of obtaining urinary exposure profiles makes this method an appealing tool for environmental epidemiology.     

Impact of climate change on residential building envelope cooling loads in subtropical climates

Future trends of cooling load due to heat gain through the building envelopes in the residential sector in subtropical Hong Kong under different emissions scenarios in the 21st century were investigated. Predicted monthly weather data from five general circulation models were gathered and analysed. An increasing trend of building envelope cooling load was observed. The average annual cooling load during the 2009-2100 period would be 6.1% and 9.8% more than that during 1979-2008 for low and medium forcing, respectively. If only the last 30 years (2071-2100) were considered, the percentage increase would be much larger at 12.3% and 21.6%. Four mitigation or energy conservation measures - raising the indoor temperature, thermal insulation, double glazing and tinted glass - were considered. Among them, raising the indoor temperature has the best mitigation potential because there is a growing awareness and recognition of adaptive thermal comfort and it can be readily applied to both existing and new buildings at no extra cost.     

航空装备MTBF动态评估与预测模型

基于航空装备可靠性增长的内在规律,将航空装备的故障分为新生故障和复发故障两类,构建了新生故障概率密度函数和故障衰减函数,导出了复发故障概率密度函数,最终建立了航空装备平均故障间隔时间(MTBF)动态评估与预测模型,并给出了模型参数确定基本算法、截尾数据处理方法和拟合优度验证方法。工程实例分析表明,模型能够客观地反映航空装备可靠性增长趋势,MTBF评估结果合理,且在一定的时间跨度内MTBF预测精度较高,误差小于10%。     

基于通用模型的风能资源特性分析

风电场风速概率分布体现了风能资源统计特性的重要指标。本文使用一种通用性强的新的风速分布模型,通过比较由风速概率分布推算出的风能特征指标估计值与由历史风速数据序列获得的实测值,说明了通用模型作为风电场风速统计模型能准确地拟合风能的实际情况,具有实用价值,为风电场规划设计提供重要参考。     

广义执行器馈能主动悬架研究

为实现车辆悬架的主动控制以及悬架振动能量的回收,提出一种基于广义执行器的馈能主动悬架.研究电磁式、液电式、气压式三种常见馈能主动悬架的特点,忽略馈能主动悬架模型的物理意义,从数学角度对广义执行器的广义功/能以及广义力进行分析,建立统一的简洁的数学模型.结合LQR和遗传算法(GA)设计控制器,实现振动能量回收,改善车辆平...