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991.
主要介绍了目前高碾压混凝土坝使用的高掺合绿色碾压拌合物、坝体防渗技术、层间结合技术、碾压混凝土入仓技术以及温控技术,可供类似工程施工借鉴。 相似文献
992.
Based on the sliding plane hypothesis of Coulumb earth pressure theory, a new method for calculation of the passive earth pressure of cohesive soil was constructed with Culmann's graphical construction. The influences of the cohesive force, adhesive force, and the fill surface form were considered in this method. In order to obtain the passive earth pressure and sliding plane angle, a program based on the sliding surface assumption was developed with the VB.NET programming language. The calculated results from this method were basically the same as those from the Rankine theory and Coulumb theory formulas. This method is conceptually clear, and the corresponding formulas given in this paper are simple and convenient for application when the fill surface form is complex. 相似文献
993.
Tak S Buchholz B Punnett L Moir S Paquet V Fulmer S Marucci-Wellman H Wegman D 《Applied ergonomics》2011,42(5):665-671
This report provides an overview of physical ergonomic exposures in highway construction work across trades and major operations. For each operation, the observational method “PATH” (Posture, Activity, Tools and Handling) was used to estimate the percentage of time that workers spent in specific tasks and with exposure to awkward postures and load handling. The observations were carried out on 73 different days, typically for about 4 h per day, covering 120 construction workers in 5 different trades: laborers, carpenters, ironworkers, plasterers, and tilers. Non-neutral trunk postures (forward or sideways flexion or twisting) were frequently observed, representing over 40% of observations for all trades except laborers (28%). Kneeling and squatting were common in all operations, especially tiling and underground utility relocation work. Handling loads was frequent, especially for plasterers and tilers, with a range of load weights but most often under 15 pounds. The results of this study provide quantitative evidence that workers in highway tunnel construction operations are exposed to ergonomic factors known to present significant health hazards. Numerous opportunities exist for the development and implementation of ergonomic interventions to protect the health and safety of construction workers. 相似文献
994.
Finite automata theory with membership values in lattices 总被引:1,自引:0,他引:1
Yongming Li 《Information Sciences》2011,181(5):1003-139
In this paper, we study finite automata with membership values in a lattice, which are called lattice-valued finite automata. The extended subset construction of lattice-valued finite automata is introduced, then the equivalences between lattice-valued finite automata, lattice-valued deterministic finite automata and lattice-valued finite automata with ε-moves are proved. A simple characterization of lattice-valued languages recognized by lattice-valued finite automata is given, then it is proved that the Kleene theorem holds in the frame of lattice-setting. A minimization algorithm of lattice-valued deterministic finite automata is presented. In particular, the role of the distributive law for the truth valued domain of finite automata is analyzed: the distributive law is not necessary to many constructions of lattice-valued finite automata, but it indeed provides some convenience in simply processing lattice-valued finite automata. 相似文献
995.
Sedat Ozer Author Vitae Chi H. Chen Author Vitae Author Vitae 《Pattern recognition》2011,44(7):1435-4123
In this study, we introduce a set of new kernel functions derived from the generalized Chebyshev polynomials. The proposed generalized Chebyshev polynomials allow us to derive different kernel functions. By using these polynomial functions, we generalize recently introduced Chebyshev kernel function for vector inputs and, as a result, we obtain a robust set of kernel functions for Support Vector Machine (SVM) classification. Thus in this study, besides clarifying how to apply the Chebyshev kernel functions on vector inputs, we also increase the generalization capability of the previously proposed Chebyshev kernels and show how to derive new kernel functions by using the generalized Chebyshev polynomials. The proposed set of kernel functions provides competitive performance when compared to all other common kernel functions on average for the simulation datasets. The results indicate that they can be used as a good alternative to other common kernel functions for SVM classification in order to obtain better accuracy. Moreover, test results show that the generalized Chebyshev kernel approaches to the minimum support vector number for classification in general. 相似文献
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给出了如何使用Matlab对现实演奏的音乐进行识别、并自动配置相应的和声的一套方法。详细分析了,从一段现有的钢琴单音旋律到最终自动产生和谐的多音色和声的整个过程。综合了物理、数学、自动化、音乐等领域的相关知识,最终实现自动给音乐配和声的功能。 相似文献
1000.
制造执行系统(MES)是企业实现信息集成的关键技术之一,而其模型的构建是MES系统设计与实现的基础.在分析典型机械制造企业生产业务流程的基础上,建立了其下料车间MES(制造执行系统)的总体模型,并从系统的功能视图、过程视图、资源视图和物理视图等不同角度对机械下料车间MES系统的体系结构进行了详细的描述.应用上述系统模型对下料车间MES系统进行了开发,并将其应用在某机械制造企业,实现了底层车间下料过程的信息化管理. 相似文献