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991.
王蕾 《自动化技术与应用》2013,32(7):131-134
热释电红外传感器被广泛的应用在报警器、人体移动检测的相关领域。本文主要讨论基于热释电红外传感器的节能广告牌设计,通过热释电红外传感器的人体检测功能,使广告牌在有路人经过时启动,达到节能的目的。 相似文献
992.
针对电动汽车底盘振动控制及其能量反馈的设计要求,建立其1/4馈能式主动悬架模型,从能量角度使用基于线性二次最优调节器(Linear Quadratic Regulator, LQR)的控制方法,使悬架在控制力作动下达到车身振动能量尽量小并获得一定的振动反馈能量.在理论分析基础上,使用与Simulink建立联合仿真系统,分析LQR控制器协调底盘在复杂工况下的振动控制及其能量反馈的综合效果.分析表明,所用LQR协调控制方法能有效协调减振及其能量反馈. 相似文献
993.
994.
首先介绍了将模拟小信号电能表与纯数字电能表的计量综合成一个系统以后的体系结构, 然后分析了在嵌入式实时操作系统uCOS-II环境下计量系统的实现: 包括任务的划分、任务间的通信以及数据的共享问题, 其中重点研究了任务间通信时数据的共享问题, 最后总结了任务间的总体通信情况, 为设计出高精度的数字电能表计量软件奠定了坚实的基础. 相似文献
995.
余建军 《中国水能及电气化》2011,(10):47-49,46
本文针对目前每个小型水电站扩容增效技改中微机监控设计和改造中必须解决的同期点选择和同期方式确定问题结合相关理论、规范,在总结常规监控方式下同类问题的解决办法基础上结合工程实际提出了切实可行解决问题的方法和依据。 相似文献
996.
王理 《中国水能及电气化》2011,(9)
微网运行特别是在孤岛情况下,由于太阳能光伏发电、风力发电的随机性较大,使得其电能的调度成为一个重要且困难的问题。针对不同分布式电源的特性以及成本,对传统意义下的微网经济调度模型进行了修正,将环境成本、发电成本和旋转备用成本作为多目标,建立了环保经济的微网多目标模型。针对3个不同的目标函数,采用NSGA-II多目标优化方法,求解多目标协调的最优解。算例结果表明,该算法和模型的收敛更快、更全面。 相似文献
997.
水资源承载力是衡量一个地区发展潜力的主要指标。在对水资源承载能力进行综合动态平衡研究的基础上,建立了区域水资源承载力模型,并将该模型应用于山西生态小水电建设研究。结果表明,①以2015年为规划水平年,山西的水资源能支撑区域容纳0.356亿人按照241m3/人的人均水资源量进行生产生活;②2015年山西共需水85.17亿m3,其中16.84亿m3用于满足工业需水,38.31亿m3用于满足农业需水,24.78亿m3用于满足生活需水,2.39亿m3用于满足生态环境持续与修复的需水;③各产业需水结构上,生活需水增幅最大,达1.47倍,工业需水次之,增幅为60%,生态需水较现状年增加80%;④区域生态小水电建设应以长治市和晋城市为重点,重点做好沁河及浊漳河水资源承载力条件下的生态小水电建设及区域生态水电建设的优化。 相似文献
998.
A simple Mathematica (version 7) code for computing S-state energies and wave functions of two-electron (helium-like) ions is presented. The elegant technique derived from the classical papers of Pekeris (1958, 1959, 1962, 1965, 1971) [1], [2] and [3] is applied. The basis functions are composed of the Laguerre functions. The method is based on the perimetric coordinates and specific properties of the Laguerre polynomials. Direct solution of the generalized eigenvalues and eigenvectors problem is used, distinct from the Pekeris works. No special subroutines were used, only built-in objects supported by Mathematica. The accuracy of the results and computation times depend on the basis size. The ground state and the lowest triplet state energies can be computed with a precision of 12 and 14 significant figures, respectively. The accuracy of the higher excited states calculations is slightly worse. The resultant wave functions have a simple analytical form, that enables calculation of expectation values for arbitrary physical operators without any difficulties. Only three natural parameters are required in the input.The above Mathematica code is simpler than the earlier version (Liverts and Barnea, 2010 [4]). At the same time, it is faster and more accurate.
Program summary
Program title: TwoElAtomSL(SH)Catalogue identifier: AEHY_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHY_v1_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 11 434No. of bytes in distributed program, including test data, etc.: 540 063Distribution format: tar.gzProgramming language: Mathematica 7.0Computer: Any PCOperating system: Any which supports Mathematica; tested under Microsoft Windows XP and Linux SUSE 11.0RAM:?109 bytesClassification: 2.1, 2.2, 2.7, 2.9Nature of problem: The Schrödinger equation for atoms (ions) with more than one electron has not been solved analytically. Approximate methods must be applied in order to obtain the wave functions or another physical attributes from quantum mechanical calculations.Solution method: The S-wave function is expanded into a triple set of basis functions which are composed of the exponentials combined with the Laguerre polynomials in the perimetric coordinates. Using specific properties of the Laguerre polynomials, solution of the two-electron Schrödinger equation reduces to solving the generalized eigenvalues and eigenvector problem for the proper Hamiltonian. The unknown exponential parameter is determined by means of minimization of the corresponding eigenvalue (energy).Restrictions: First, the too large length of expansion (basis size) takes the too large computation time and operative memory giving no perceptible improvement in accuracy. Second, the number of shells Ω in the wave function expansion enables one to calculate the excited nS-states up to n=Ω+1 inclusive.Running time: 2–60 minutes (depends on basis size and computer speed). 相似文献999.
P. Bechtle O. Brein S. Heinemeyer G. Weiglein K.E. Williams 《Computer Physics Communications》2011,182(12):2605-2631
HiggsBounds 2.0.0 is a computer code which tests both neutral and charged Higgs sectors of arbitrary models against the current exclusion bounds from the Higgs searches at LEP and the Tevatron. As input, it requires a selection of model predictions, such as Higgs masses, branching ratios, effective couplings and total decay widths. HiggsBounds 2.0.0 then uses the expected and observed topological cross section limits from the Higgs searches to determine whether a given parameter scenario of a model is excluded at the 95% C.L. by those searches. Version 2.0.0 represents a significant extension of the code since its first release (1.0.0). It includes now 28/53 LEP/Tevatron Higgs search analyses, compared to the 11/22 in the first release, of which many of the ones from the Tevatron are replaced by updates. As a major extension, the code allows now the predictions for (singly) charged Higgs bosons to be confronted with LEP and Tevatron searches. Furthermore, the newly included analyses contain LEP searches for neutral Higgs bosons (H) decaying invisibly or into (non-flavour tagged) hadrons as well as decay-mode independent searches for neutral Higgs bosons, LEP searches via the production modes τ+τ−H and , and Tevatron searches via . Also, all Tevatron results presented at the ICHEP?10 are included in version 2.0.0. As physics applications of HiggsBounds 2.0.0 we study the allowed Higgs mass range for model scenarios with invisible Higgs decays and we obtain exclusion results for the scalar sector of the Randall–Sundrum model using up-to-date LEP and Tevatron direct search results.
Program summary
Program title: HiggsBoundsCatalogue identifier: AEFF_v2_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEFF_v2_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: GNU General Public Licence version 3No. of lines in distributed program, including test data, etc.: 74 005No. of bytes in distributed program, including test data, etc.: 1 730 996Distribution format: tar.gzProgramming language: Fortran 77, Fortran 90 (two code versions are offered).Classification: 11.1.Catalogue identifier of previous version: AEFF_v1_0Journal reference of previous version: Comput. Phys. Comm. 181 (2010) 138External routines: HiggsBounds requires no external routines/libraries. Some sample programs in the distribution require the programs FeynHiggs 2.7.1 or CPsuperH2.2 to be installed.Does the new version supersede the previous version?: YesNature of problem: Determine whether a parameter point of a given model is excluded or allowed by LEP and Tevatron neutral and charged Higgs boson search results.Solution method: The most sensitive channel from LEP and Tevatron searches is determined and subsequently applied to test this parameter point. The test requires as input, model predictions for the Higgs boson masses, branching ratios and ratios of production cross sections with respect to reference values.Reasons for new version: This version extends the functionality of the previous version.Summary of revisions: List of included Higgs searches has been expanded, e.g. inclusion of (singly) charged Higgs boson searches. The input required from the user has been extended accordingly.Restrictions: Assumes that the narrow width approximation is applicable in the model under consideration and that the model does not predict a significant change to the signature of the background processes or the kinematical distributions of the signal cross sections.Running time: About 0.01 seconds (or less) for one parameter point using one processor of an Intel Core 2 Quad Q6600 CPU at 2.40 GHz for sample model scenarios with three Higgs bosons. It depends on the complexity of the Higgs sector (e.g. the number of Higgs bosons and the number of open decay channels) and on the code version. 相似文献1000.
针对传统基于语义服务动态合成的低效率和授权管理的有效性不高,提出了基于行为能力约束的服务动态授权管理方法。该方法借助数学优化模型,对服务合成的路径进行了描述,根据成份服务间的约束关系,提出了协同应用服务动态合成算法。基于行为能力约束,将服务合成的语义推理进行预先处理,探索构成协同应用服务的最小行为能力,根据服务请求用户所拥有的行为能力与协同应用服务所需的最小行为能力的关系进行判断授权,避免了用户提出服务请求时的大规模空间搜索和服务语义间的推理计算问题。实验结果分析表明,该方法提高了服务授权管理的自动化程度和有效性,并且具有较高的动态适应能力。 相似文献