关于城市核心竞争力的思考

城市核心竞争力区别于城市一般所具备的基本资源与能力．是城市获取各种资源、求得发展的的关键所在。城市核心竞争力作为城市持续竞争优势的源泉．对现代城市的发展起着至关重要的作用。本文首先分析界定了城市核心竞争力的定义．接着提出城市核心竞争力的着力点。落脚点．最后分析归纳了城市核心竞争力的特点。     

Architecture,Utopia and the futures of the avant-garde

This paper reviews some current manifestations of Marxist thought within and around architectural discourse, building on papers presented at a symposium held at the University of Westminster in May, 2004.     

Assessing the effect of nutrient mitigation measures in the watersheds of the Southern Bight of the North Sea

The Seine, Somme, and Scheldt Rivers (France, Belgium, and Netherlands) are the major delivering rivers flowing into the continental coastal zone of the Southern Bight of the North Sea, an area regularly affected by eutrophication problems. In the present work, the Seneque-Riverstrahler model was implemented in a multi-regional case study in order to test several planned mitigation measures aimed at limiting stream nutrient contamination and restoring balanced nutrient ratios at the coastal zone.This modeling approach, which is spatially distributed at the basin scale, allows assessing the impact of any change in human activities, which widely differ over the three basins. Here, we define realistic scenarios based on currently proposed measures to reduce point and non-point sources, such as the upgrading of wastewater treatment, the introduction of catch crops, and the development of extensive farming. An analysis of the current situation showed that a 47-72% reduction in P point-source emissions within the three basins could be reached if the intended P treatment was generalized to the largest treatment plants. However, only an overall 14-23% reduction in N could be achieved at the outlet of the three basins, by combining improved wastewater treatment and land use with management measures aimed at regulating agricultural practices. Nonetheless, in spite of these efforts, N will still be exported in large excess with respect to the equilibrium defined by the Redfield ratios, even in the most optimistic hypothesis describing the long-term response of groundwater nitrate concentrations.A comprehensive assessment of these mitigation measures supports the need for additional reductions of nutrient losses from agriculture to control harmful algae development. It also stresses the relevance of this mechanistic approach, in which nutrient transfers from land to sea can be calculated, as an integrated strategy to test policy recommendations.     

氧化锌压敏电阻片冲击大电流残压特性的研究

在大量试验数据的基础上,分析和研究了瞬态大电流的波形参数、冲击电流幅值以及氧化锌压敏电阻片表面积对氧化锌压敏电阻残压的影响。针对几种典型的试验用电流波形参数,归纳出冲击电流幅值与残压之间的变化规律,其对于估算一定电流波形下某幅值对应的残压数值,或者对现有试验结果进行验证具有一定的参考。     

离子液体处理油基钻屑的研究

石窟寺数字化工程中获取了大量的数据,包括：点云数据、三维模型、纹理数据以及各种图件等。针对这些数据的管理,本文提出基于文件与数据库的混合管理方法,设计并实现了具有普适性的石窟寺数字化工程数据管理系统。该系统目前已经应用在宝顶山大佛湾石刻数字化工程中。实践结果表明,采用文件与数据库混合管理方法可以有效地管理石窟寺数字化工程数据,同时,系统的应用能够提高数据的查询和使用效率。     

Cities on the Edge of Chaos

Is the mass-customised city no more than a smokescreen, a re-evocation of Modernist positivism and its problem-solving ideology? Colin Fournier , Emeritus Professor of Architecture and Urbanism at the Bartlett School of Architecture, University College London (UCL), and Visiting Professor at the Chinese University of Hong Kong (CUHK), questions the premise of this issue and asks if the variation required for a city's survival ‘at the edge of chaos’ lies beyond mass customisation.     

跨界谜局

作为营利组织,在利润最大化的激励下,从创建伊始,发展就是企业的核心目标,企业的一切活动均以企业发展为导向。在外部环境不确定、市场竞争激烈和新兴产业不断涌现的条件下,企业只有寻求发展、适应环境变化才能在竞争中生存。跨界布局是企业获得新的经济增长点,持续发展而采取的战略选择之一。企业发展是量的增长和质的改善的有机结合,片面地追求量的增长而不进行企业产品结构、资本结构、人员素质和组织管理等方面质的改善,会陷入增长危机。一个企业并不一定要做得更大,但必须变得更好。企业实施跨界战略的目的更多是希望产品结构、资本结构等方面得到质的改善,在此基础上,同时在生产规模、资本规模、市场占有率及产品产值等指标数量上获得增长。跨界也是实施基于核心竞争力的变革,即按照能够体现核心竞争力的原则选择业务组合和适当的组织结构、流程制度、管理风格、公司文化等要素来进入一个新的产业、新的市场,从而进化出新的核心竞争能力。近年来,在国内固定资产投资高速增长的支撑之下,我国工程机械行业也呈现高速增长态势,伴随着逐步扩大的市场需求和销售额度、利润额度的冲高,一些外来者开始跨界进入到工程机械行业,这些跨界行为有着哪些共性和差异性,动力机制如何,又会为国...     

北京东城余园

余园位于北京东城东厂胡同,原为清代大学士瑞麟的宅园.此园规模很大,建筑密度较小,而且基本上集中于东南一区,西部则为大片空地,体现出文人园疏朗朴素的气质.园中设有八角形西洋式建筑,兼作观景平台;园中假山主要以土山为主,在一些关键部位和重点景区堆叠青石,东部辟有长形水池,通过假山上的蓄水池注水;花木以单株欣赏与成片效果相映衬,辅以紫藤架,景色幽胜.通过文献考证和现场调研,对这座宅第花园的历史沿革、基本布局以及造园手法进行了探讨.     

Experimental study of the effects of a thermal plume entrainment mode on the flow structure: Application to fire

The aim of this work is to experimentally simulate two heat sources of fire, one placed at ground level, the other at a height above the ground, in order to determine the effect of source air entrainment on the resulting flow structure. The development of a free thermal plume was examined by generating a plume produced from an electrically heated disk at a constant temperature. We first studied the behavior of a thermal plume induced by a disk embedded in a horizontal plate placed at the level of the ground. This configuration ensured a regular lateral entrainment of air to the plume. The analysis of the average fields as well as the axial evolution of velocity and temperature showed an important widening of the profiles that encouraged a faster spread of the plume. We then determined the structure of the thermal plume generated by the same source placed at a height above the ground, ensuring simultaneous vertical and lateral entrainment of air into the resulting plume.     

桥梁结构地震作用破坏准则的探讨

针对目前国内外学者提出的众多桥梁结构地震破坏准则进行了综述,并对各种破坏准则的优缺点进行了比较,指出确定一个合理的破坏准则是减轻地震损失最有效的方法,以期最大限度地减小地震损失.     

Spatial impact of factors influencing the achievement of the Europa2020 employment targets

In this paper, autologistic models are used to examine the impact of certain factors on the likelihood of European regions' ability to meet the employment target for both men and women for the year 2017 in 270 EU regions at NUTS 2 level. The results show the role of both regional and gender differences in forming spatial clusters, as well as the presence of spatial interaction in achievement of the target. Moreover, meeting the European strategy's education target and increasing a region's GDP levels also have a positive impact on achieving the targets. These findings may be of interest for the implementation of socio-economic policies at a regional level, aimed at raising the employment rate for men and women in European regions.     

轻质装配式叠合楼板拼接处受力性能试验研究

提出了一种轻质装配式叠合楼板,由压型钢板、带桁架钢筋轻质陶粒混凝土预制层及普通混凝土现浇层三部分组成,在拼接处增设构造钢筋并用栓钉将楼板与钢梁焊接。分析了各级加载下试件在拼接处的抗弯承载力、挠度以及裂缝等力学性能指标。结果表明,拼接处的构造措施能有效提高叠合楼板的承载力和变形能力;与普通叠合楼板相比,该种楼板具有自重低、承载力高、延性好及施工效率高等特点,具有广阔的应用前景。     

可行性研究阶段商品住宅项目投资估算的方法

为了准确地把握投资机会,开发商必须借助科学的估算方法和先进的计算工具,提高可行性研究阶段投资估算的准确性,通过对现行的估算方法进行介绍和总结,为优选出适合于可行性研究阶段商品住宅项目的投资估算方法打下了基础。     

城市立交桥绿地景观设计

介绍立交桥绿地景观发展的历史沿革。着重分析立交桥绿地景观的特性,总结、归纳了当前立交桥绿地景观布局的几种主要形式。进而,通过包头210国道和徐州市迎宾大道改造工程中绿地景观的工程实践,从深层次的设计内涵和景观表达,探索了城市环境中立交绿化景观发展的新趋势。     

岩石变形与渗透率演化关系研究

针对带压开采煤层底板岩层阻水性问题,进行底板岩体试样伺服渗透试验,分析了岩体试样渗透率与变形破坏演化相互关系.结果表明,全应力-应变过程岩样渗透率可划分为原始空隙渗透率和加载破坏渗透率两种,在压密-弹性段内,岩石的渗透率多表现为原始空隙渗透率,稳定破裂-裂纹扩展段内,则多表现为加载破坏渗透率;岩石突增点处应力、应变为峰...     

建国后广州会展建筑建设情况及特点研究

根据建国后广州会展建筑的发展状况,将其发展时期主要分为两个阶段：解放初期的建设以及改革开放后的蓬勃发展建设阶段,并分别讨论两个不同阶段中会展建筑的建设状况及具体的案例研究,以指导目前会展建筑设计工作。     

换流变阀侧套管封堵结构耐火极限研究

特高压换流站因换流变故障多次发生火灾事故,火势通过换流变阀侧套管封堵部位进入阀厅,导致换流阀厅损毁,为提高换流站消防安全裕度,阐述了现有换流变压器阀侧套管洞口封堵结构形式,论述了封堵结构耐火极限评价方法,针对现有封堵结构的不足,在保持大封堵结构不拆除的情况下,对封堵结构进行耐火性能增强设计,形成新的封堵结构增强系统,并依据新的评价标准对其进行耐火极限试验,结果表明该增强系统具有较好的隔热性能、完整性能,满足3 h 碳氢温升曲线的耐火极限要求,为在运换流站阀侧套管封堵结构消防改造提供解决方案。     

On the basis of the environmental temperature procedure

The procedure advanced by Danter and developed by Loudon at the Building Research Establishment, Watford, represents a major improvement in the means available to the building services engineer and architect to estimate the thermal response of some part of a building. This paper re-examines its basis.The twin roles of radiation and convection as means of transferring heat within an enclosure are first discussed. The concept of a single representative temperature to describe heat loss from the enclosure, the conductances between this central temperature and its several constituents, and the possibility of taking all heat to be input at this temperature are introduced step-by-step. It is then shown that in an enclosure so idealised to entail two surface and one air temperature, these conductances appear simultaneously by a delta to star transformation of the physical conductances, and that the star temperature t_ec so introduced is an overall measure of the enclosure temperature without an internal heat source. The environmental temperature t_ei calculated by equation (A5.18) of the IHVE 1970 Guide is shown to be nearly equal to the duly weighted combination of t_ec and the temperature t_hb of a suitable hot body source of heat contained within the enclosure. t_ei thus serves as the temperature at which this heat can be considered to be input, and from which it is lost by conduction through the fabric or by ventilation. If the heat is input by some other source (such as a convector) it may be convenient to scale it to make it equivalent to an input at t_ei. Account can be taken of periodic variation in an internal source by including the admittance of the wall construction in a manner formally similar to the steady state transmittance of the wall.     

连续梁桥在桩-土共同作用下的隔震效果分析

建立了澳门澳凼第三大桥的9跨连续梁桥的梁体、桥墩和基础共同工作的空间有限元分析模型,建立了3种桥梁支座形式的弹簧单元恢复力模型;并分别在顺、横桥向输入EL-Centro波进行连续梁桥的对比时程分析。研究表明:采用铅芯橡胶支座能延长结构的周期;减小桥墩底部的弯矩和剪力,并使剪力得以合理分配;同时梁体位移也得到控制,隔震效果显著。     

浅谈上部结构—地下室—地基基础的相互作用

指出高层建筑的上部结构、地下室、地基基础三者在荷载作用下都是有机地共同作用、相互协调变形的,基础设计的潜力很大,通过对基础底板内在潜力、地下室的潜在功能与作用的分析就设计基础的截面及配筋方面进行了探讨,以充分挖掘基础设计潜力。