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81.
82.
暴雨强度公式是城镇排水工程设计的基本依据之一。为提高暴雨衰减指数随重现期显著变化时暴雨强度公式的拟合精度,结合实例研究了采用麦夸尔特法确定衰减指数为函数型的五参数暴雨强度公式的方法。计算结果表明,五参数暴雨强度公式能显著提高拟合精度,由该公式计算的残差平方和及各重现期的绝对均方差(即标准差)均明显小于四参数公式的计算结果,其各重现期的绝对均方差均小于0.05mm/min。该方法能有效降低重现期较小与较大时的绝对均方差。此外,给出了麦夸尔特法的计算程序框图,为编写计算程序代码奠定基础。 相似文献
83.
《Ergonomics》2012,55(5):446-454
The objective of this study was to investigate the effects of load height and foot placement on the functional base of support (FBOS) limits and the postures that participants used when they reached their FBOS limits. Twelve young male participants were tested while holding a 12-kg load at reach (above their heads), at shoulder and knuckle height, and unladen under both wide and narrow foot placements. The FBOS limits and the centre of pressure (COP) excursion length were calculated based on data from a force platform. Postural angles when participants reached their FBOS limits were calculated from records of a 2-D motion analysis system. The results showed that the load height had greater effect on the posterior FBOS limit. As the load height decreased, the COP excursion length decreased. Participants were prone to using a hip strategy to maintain postural balance when reaching their FBOS limits. Quantitative data of FBOS limits and postural control while participants hold a load at various heights when reaching their FBOS limits is of value for designing a safe materials handling workplace. 相似文献
84.
李萍 《江汉石油职工大学学报》2013,(6):76-77,80
在当代社会体系中,女性是维系家庭、企业、社会和谐的重要力量,构建和谐企业,同样离不开广大女职工的全力参与。她们具有不可替代的职能优势、不可低估的组织优势,还有传统的阵地优势。这些优势有利于她们在企业中,强化职能意识,健全维权机制;树立品牌意识,提升服务品质;丰富活动内涵,展示时代风采,为企业和谐有效发展做出应有贡献。 相似文献
85.
Fengmin Le Ivan MarkovskyChristopher T. Freeman Eric Rogers 《Control Engineering Practice》2012,20(4):386-396
Modeling of electrically stimulated muscle is considered in this paper where a Hammerstein structure is selected to represent the isometric response. Motivated by the slowly time-varying properties of the muscle system, recursive identification of Hammerstein structures is investigated. A recursive algorithm is then developed to address limitations in the approaches currently available. The linear and nonlinear parameters are separated and estimated recursively in a parallel manner, with each updating algorithm using the most up-to-date estimation produced by the other algorithm at each time instant. Hence the procedure is termed the alternately recursive least square (ARLS) algorithm. When compared with the leading approach in this application area, ARLS exhibits superior performance in both numerical simulations and experimental tests with electrically stimulated muscle. 相似文献
86.
Characterization of Fractionated Soy Proteins Produced by a New Simplified Procedure 总被引:2,自引:0,他引:2
Nicolas A. Deak Patricia A. Murphy Lawrence A. Johnson 《Journal of the American Oil Chemists' Society》2007,84(2):137-149
It was possible to fractionate soy protein into two soy protein isolate fractions (>90% protein) enriched in either glycinin
or β-conglycinin by using a new simplified procedure (referred to as the Deak procedure) employing CaCl2 and NaHSO3. The Deak procedure produced fractions with higher yields of solids, protein, and isoflavones, and similar protein purities
as well as improved functional properties compared to fractions recovered by established, more complex soy protein fractionation
procedures. The Deak glycinin-rich fraction comprised 15.5% of the solids, 24.4% of the protein, and 20.5% of the isoflavones
in the starting soy flour, whereas the glycinin-rich fraction of the established procedure (Wu procedure) comprised only 11.6%
of the solids, 22.3% of the protein, and 9.6% of the isoflavones. The Deak β-conglycinin-rich fraction comprised 23.1% of
the solids, 37.1% of the protein, and 37.5% of the isoflavones in the starting soy flour, whereas the Wu β-conglycinin-rich
fraction comprised only 11.5% of the solids, 18.5% of the protein, and 3.3% of the isoflavones. Protein purities were >80%
for both fractions when using both procedures. The Wu procedure produced protein fractions with slightly higher solubilities
and similar surface hydrophobicities; whereas, the fractions produced by the Deak procedure had superior emulsification and
foaming properties and similar dynamic viscosity behaviors. 相似文献
87.
The collaborative research center “Textile Reinforced Concrete (TRC) – Development of a New Technology” (SFB 532) established at Aachen University (RWTH Aachen) is investigating the basic mechanisms of this new composite material. The use of technical textiles as reinforcement material in cementitious binder systems allows the production of thin-structured elements as will be dimensioned, modelled, and produced within the research project. For this reason the material properties of the single components have to be known and will be integrated in analytical and numerical simulations of textile reinforced structures. Thus key parameters on the meso-level are introduced. These are on the one hand the tensile strength and elastic modulus of filaments and rovings, on the other hand mechanical and fracture mechanical parameters of the matrix, and finally the bonding characteristics of filaments as well as rovings embedded in the cement based matrix. 相似文献
88.
89.
介绍了安全相关系统在实际应用中的需求,并研究了安全相关系统在设计、开发、应用、维护等过程中应遵循的标准。说明了安全相关系统的功能安全认证流程,并给出了安全相关系统的V模式开发模型。 相似文献
90.
基于EPA标准的执行机构产品开发 总被引:1,自引:2,他引:1
介绍了基于EPA标准的执行机构的工作原理,详细介绍了EPA通信卡的硬件设计,并阐述了基于模块化的软件设计,主要包括EPA用户应用程序、EPA协议栈软件和硬件驱动等主要模块。从而使执行机构具有基于EPA标准的工业以太网通信能力,同时利用EPA标准的多信息传输能力,实现了执行机构的远程组态、远程标定和远程故障诊断等功能,达到了执行机构设备智能化、数字化和网络化的目的,具有广阔的应用前景。 相似文献