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121.
为得出直墙拱形巷道围岩应力分布规律,应用复变函数弹性理论推导了直墙拱形巷道围岩应力分布的解析表达式。对直墙拱形巷道边界的围岩应力和巷道水平线方向的围岩应力分布规律进行分析,并考虑直墙拱形巷道断面高宽比和侧压系数对其影响规律。研究表明:在不同巷道断面高宽比、侧压系数下,直墙拱形巷道围岩应力集中区域主要集中在直墙底部底角处、拱形顶板中点附近和底板中部3个位置。不同巷道断面高宽比下,直墙拱形巷道沿水平线的应力分布规律基本相同。侧压系数大于1时,采用巷道断面高宽比小于1较有利于巷道稳定;侧压系数小于等于1时,采用巷道断面高宽比大于1较有利于巷道稳定。  相似文献   
122.
This paper analyzes the current situation of university students' credit evaluation and set up an evaluation index system of university students' credit to compensate a loan.Based on this index system,this paper sets up a matter-element evaluation model on the individual credit of university students loan by means of extensible engineering method.The grade of individual credit and the index for evaluating the level of individual credit are made as matter-element,meanwhile,the classical field,the segment field,the weight coefficient are obtained.Dependence function is established based on the grade of individual credit and then the grade is judged by calculating the synthetic dependence degree.Finally,this paper presents the evaluation method by giving an example.This method is simple in calculation,reasonable in evaluation with high applicability.  相似文献   
123.
For certain types of inventory, the ordering cycle and demand may be random variants, which satisfy certain types distribution. The classical EOQ model usually neglects the fact. Based on the constant demand, under the hypothesis that the ordering cycle is a random variant which satisfies exponent distribution, average demand is a linear increasing function, this paper considers the effects of the time-value of capital and inflation on replenishment strategy of inventory system. Loosening the condition of basic economic order quantity model under deterministic state, the total cost function of the model is provided. The optimum order quantity and cycle are obtained. The application range of EOQ model under the constant demand is widened. The theoretical evidence is provided for the inventory system to make management decision.  相似文献   
124.
The kernel function of kernel estimator for regression function is often defined with compact support, the moment of Y is bigger than one. The convergence rate of the improved kernel estimator is discussed under the improved kernel function. The result is also discussed under random censorship. The class of applicable kernels include those having unbounded support and even not integral .The condition of moment of Y is discarded under the improved kernel estimator. The results are wholly the same as usual and generalize the relative results of the paper .  相似文献   
125.
In order to subdivide the market during the process of project planning and orient the group of client, then determine the sale price; on the condition that the traditional orientation procedure cant grasp the payment capability of the aim client, the anthors can adapt the powerful finance analysis ability of EXEL to design the procedure of determining the purchasing power and payments ability of the aim client, and shape a set of orientation system based on quantitative analysis method. The result is, the character of the aim client can be grasp accurately depend on this orientation system, and providing a scientific gist for the accurate orientation of price and lowing the risk of investment etc.  相似文献   
126.
In this paper, partial differential equations of vortex flow-stream function in boundary fitted coordinates and related ADI equations were listed. The flow around a cylinder in quadrilateral area by auto control boundary was computed. The diagram of distribution of speed arrow, constant lines of flow-stream function, vortex, two speed parts and pressure were studied.  相似文献   
127.
For the inequality constrained nonlinear programming problem, the antnors propose a new lower order penalty function, which combines the classical l1 penalty function and the lower order exact penalty function introduced in thoy some papers, and then illustrate that it has the merits of the two penalty functions. In additional, we propose a solution method for solving the inequality constrained nonlinear programming problem and prove its global convergence.  相似文献   
128.
In this paper, a necessary optimality condition of problems with equality constraints is investigated by the implicit function theorem in n-dimensional Euclidean space. A new approach solving these problems is obtained. The number of dimensions of corresponding system of equations is less than the classic Lagrangian multiplier method.  相似文献   
129.
急、慢性冷应激对雏鸡腓肠肌及血清抗氧化功能的影响   总被引:5,自引:0,他引:5  
【目的】探讨自由基在冷应激对禽类机体损伤中所起的作用,为探索促进动物冷适应的方法,提高动物的抗寒能力提供一定的理论依据;【方法】应用化学比色法检测了急、慢性冷应激对腓肠肌和血清中总抗氧化能力(T-AOC)、过氧化氢酶(CAT)活性、谷胱甘肽过氧化物酶(GSH-Px)活性、超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量的影响;【结果】急性应激时,随应激时间的延长,腓肠肌T-AOC与SOD活性均逐渐降低,GSH-Px活性、CAT活性及MDA含量均逐渐升高,血清T-AOC逐渐降低,GSH-Px活性、CAT活性、SOD活性及MDA含量均逐渐升高;慢性应激时,随应激时间的延长,腓肠肌T-AOC、GSH-Px活性、CAT活性及SOD活性均逐渐升高,MDA含量逐渐降低,血清T-AOC、GSH-Px活性、CAT活性及MDA含量均逐渐升高,SOD活性逐渐降低;【结论】表明急、慢性冷应激均可使机体的抗氧化功能发生改变,诱发氧化胁迫,导致机体内自由基增多,对机体造成损伤。  相似文献   
130.
Membership functions.formed with the characteristic values obtained by applying the continuous reaction time (CRT) theory from controls and heptic encephalopthy and proposedin this paper.whith these membership functions,the CRT data to be diagnosed are calculated in advance,and then discriminated by BP meural network to differentiate patients with or without braindysfunction.The troubles of low accuracy and efficiency,encountered in training BP network withfuzzy samples.scattered data and extended samples,are solved.  相似文献   
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