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71.
企业家共同社会责任是指一个企业或“企业公民”对社会应该承担的义务,涉及到企业与相关利益群体之间的相互关系和价值观、操守以及对人的尊重、社群和企业的环境政策等各个方面。很明显,这一概念的核心是企业对基于经济、社会和环境可持续发展的一种责任和承诺,以改善和提高利益相关方的生活水准和条件。当前,企业家共同社会责任不再仅仅是一种道德伦理而已,而且已经成为一种制度性的自律和规定行为。目前的共识是,在运营过程中一个企业必须时刻关注它对客户、员工、股东、社群、地区发展和环境的经济、社会和道德后果,并使它们取得一个比较好的前景。基于这一观点和理念,本文以跨国公司企业家共同社会责任为视角,主要探讨了跨国公司研发活动与上海浦东新区——我国新经济的高地之一——发展的相互作用,以探索跨国公司研发活动、地区经济增长以及它们在形成灵活创新网络、促进可持续发展中的不同功能和共同作用。内容包括六个部分:1)企业家共同社会责任的相关概念及其关系;2)跨国公司在浦东研发活动的现状和态势;3)跨国公司研发活动与地区经济的联系模式和紧密程度;4)跨国公司在浦东研发活动中存在的主要问题;5)地区灵活创新网络的内涵;6)形成灵活创新网络的方式和途径。  相似文献   
72.
地质力学模型试验均布压力精确加载是保证试验精度的前提。为此研制了一种新型柔性均布压力加载系统,该系统主要包括液压自动控制系统和柔性均布压力加载装置。液压自动控制系统操作方便,可实现计算机自动控制12路压力精确伺服加、卸载和长期稳压。柔性均布压力加载装置由液压油缸、球铰、刚性推力器和柔性传力橡胶垫块等组成,采用数值方法确定柔性橡胶的厚度为50 mm。该系统应用到表面不平的模型加载中并与刚性加载进行了对比。试验结果表明,柔性均布压力加载系统相对于刚性加载效果显著,模型内应力场均匀程度取决于橡胶传力垫块的邵氏硬度、加载应力大小和距表面深度。邵氏硬度小的橡胶柔性加载模型内应力场更均匀;且模型应力场随加载应力增大趋于均匀。模型内应力场距加载表面越远越均匀,柔性加载使距加载表面130 mm以下应力场基本保持均匀状态。试验表明,柔性均布压力加载系统有利于提高模型试验加载精度,具有广泛的应用前景。  相似文献   
73.
李春英  吴志强 《安徽地质》2009,19(3):222-224
黄山风景区钓小旅游公路全长3.9km,其间有五个边坡稳定性较差,故对此进行加固治理。本文浅谈治理工程中的SNS柔性防护网的应用。  相似文献   
74.
《水文科学杂志》2013,58(4):905-920
Abstract

A one-dimensional steady-state model was constructed and used to study vertical profiles of longitudinalvelocities in open channel flows through, and above, submerged vegetation. The eddy viscosity was evaluated by using the analogue of the mixing length theory. The model of water velocity profiles takes into account the surface roughness of the channel bottom and the drag exerted by submerged flexible stems. The verification of the calculated velocity profiles was carried out based on data obtained in laboratory experiments. The proportionality coefficients for the analogue of the mixing length formulae in both layers—within homogenous flexible stems and above them—were determined.  相似文献   
75.
Many studies have tackled the problem of vortex-induced vibrations (VIV) of a vertical riser with a constant tension and placed in uniform currents. In this study, attention is focused on the cross-flow VIV modelling, time-domain analysis and prediction of variable-tension vertical risers in linearly sheared currents. The partial-differential equation governing the riser transverse motion is based on a flexural tensioned-beam model with typical pinned-pinned supports. The hydrodynamic excitation model describing the modulation of lift force is based on a distributed van der Pol wake oscillator whose nonlinear equation is also partial-differential due to the implementation of a diffusion term. The variation of empirical wake coefficients with system parameters and the water depth-dependent Reynolds number is introduced. Based on the assumed Fourier mode shape functions obtained by accounting for the effect of non-uniform tension, the Galerkin technique is utilized to construct a low-dimensional multi-mode model governing the coupled fluid-riser interaction system due to VIV. Numerical simulations in the case of varying sheared flow profiles are carried out to systematically evaluate riser nonlinear dynamics and highlight the influence of fluid-structure parameters along with associated VIV aspects. In particular, the effects of shear and tensioned-beam (tension versus bending) parameters are underlined. Some comparisons with published experimental results and observations are qualitatively and quantitatively discussed. Overall parametric analysis and prediction results may be worthwhile for being a new benchmark against future experimental testing and/or numerical results predicted by an alternative model and methodology.  相似文献   
76.
舟曲“8.8”特大泥石流灾后治理中的关键技术研究是治理工程首先需要解决的问题,包括3个关系,即泥石流流量与排导沟断面关系、泥石流冲击力与拦挡坝强度关系、泥石流物源级配与柔性防护拦疏关系。提出了长流水小排水槽、一般山洪泥石流中排导槽、特大山洪泥石流生态景观休闲大缓冲区的设计理念,解决了百年一遇泥石流对排导沟流量与断面的设计要求。提出用钢混结构重力式拦挡墙替代原有浆砌块石重力式拦挡墙,满足了坝体对冲击力与强度的关系。建议在流通区设置SNS柔性防护网,采用钢丝绳环形网在发挥拦挡的同时达到泄水的要求。研究成果对于舟曲泥石流灾后治理设计方案具有科学价值。  相似文献   
77.
Along with the consumption increase of the petroleum products,more countries have transferred their attentions to the offshore fields,especially the deepwater oil and gas reserves.For deepwater exploitation,the risers must be installed to act as the conduits connecting surface platforms to subsea facilities.In this paper,the typical risers sorted by different classes are introduced,and the correspondent installation methods are presented.By investigating the recent projects performed in the deepwater hot spots,and combining the challenges of HYSY201 for riser installation,a lifting device developed for assisting riser installation is proposed and detailed to satisfy the installation of deepwater risers in the LW3-1 Gas Field of in the South China Sea.Tests on both the functions and performances of such a new system exhibit the satisfaction of meeting all challenging requirements of HYSY201 for application to riser installation in waters up to a depth of in the South China Sea.  相似文献   
78.
康庄  李辉  孙丽萍  冯玮  贾旭 《海洋工程》2011,29(4):43-50
由于良好的疲劳特性,自由站立式立管(FSHR)正广泛应用于深海油气田的开发当中。首先根据设计参数建立FSHR详细的有限元模型,然后利用谱分析方法对FSHR进行总体运动疲劳分析,以确定FSHR总体设计参数是否满足运动疲劳要求。最后对工作于相同环境下的钢悬链立管(SCR)进行总体运动疲劳分析,探讨哪种立管系统的疲劳性能更为优良。计算结果表明FSHR系统中刚性主管最大运动疲劳损伤出现在刚性主管顶部,FSHR总体设计参数满足规范要求;FSHR总体运动疲劳寿命要远大于SCR,体现了FSHR系统对浮体运动与刚性主管之间具有良好的解耦作用。  相似文献   
79.
This paper reports on the investigation of novel fiber reinforced elastomeric isolator (FREI) bearings, which do not have thick end plates, and are used in an unbonded application. Owing to the stable lateral load‐displacement response exhibited by the unbonded FREI bearings, the proposed bearings are referred to as stable unbonded (SU)‐FREIs. A shake table test program was conducted on a two‐story test‐structure having well‐defined elastic response characteristics. Compared with the results for the corresponding fixed base (FB) structure, the peak response values, distribution of lateral response throughout the height of the structure, and response time histories of the tested base isolated (BI) structure indicate that significantly improved response can be achieved. This study clearly indicates that SU‐FREI bearings can provide an effective seismic isolation system. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
80.
This work presents a simple and efficient framework for the fatigue reliability assessment of a vertical top-tensioned rigid riser. The fatigue damage response is considered as a narrow-band Gaussian stationary random process with a zero mean for the short-term behavior of a riser. Non-linearity in a response associated with Morison-type wave loading is accounted for by using a factor, which is the ratio of expected damage according to a non-linear probability distribution to the expected damage according to a linear method of analysis. Long-term non-stationary response is obtained by summing up a large number of short-term stationary responses. Uncertainties associated with both the strength and stress parts of the limit state function are quantified by a lognormal distribution. A closed form reliability analysis is carried out, which is based on the limit state function formulated in terms of Miner’s cumulative damage rule. The results thus obtained are compared with the well-documented lognormal format of reliability analysis based on time to fatigue failure. The validity of using the lognormal hazard rate function in predicting the fatigue life is discussed. A Monte Carlo simulation technique is also used as a reliability assessment method. A simple algorithm is used to reduce the uncertainty associated with direct sampling at small probability of failure values and a small number of simulations. Simulation results are compared with closed form solutions. A worked example is included to show the practical riser design problem based on reliability analysis.  相似文献   
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