首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 8 毫秒
1.
A new trust region algorithm is proposed for solving unconstrained optimization problems. According to the quadratic approximate model of the original optimization problem,the trust region algorithm uses directions,a convex combination of the quasi-newton direction and the steepest descent direction. This algorithm with new strategy is analyzed and the global and local quadratic convergent theorems are proved. At last,the implementation and computational results of the algorithm are demonstrated.  相似文献   

2.
In order to improve the convergence rate of the algorithms, an acceleration search method along a straight or curve is proposed,and the specific calculation steps of the algorithms are presented. The numerical results in model parameter estimation show that the convergence rate is improved and the calculation accords with the practical demands.  相似文献   

3.
An approach for evaluating the performance of relational database is introduced, the stroage cost, responding time and maintenance ccst oi a relational database based on B+ tree index are theoretically analyzed, and the evaluation model is proposed  相似文献   

4.
对免疫亲和层析净化高效液相色谱法测小麦中呕吐毒素含量的不确定度进行了评定.参照JJF 1059.1-2012《测量不确定度评定与表示》和CNAS-GL006《化学分析中不确定度的评估指南》,分析测量过程中引入的不确定度分量,计算测量结果的不确定度.通过比较各分量,得出影响检测结果不确定度的主要因素是:试液浓度、精密度和...  相似文献   

5.
A processing method for the weight of the object in the fuzzy solving method for the multiojectide optimization are presented. The methods are using different type of membership functions and using the same kind membership function adjusting the parameter. Some corresponding analysis and examples are discussed and the results show that the two methods are very effective.  相似文献   

6.
This paper presents two trust region algorithms for solving general nonlinear equality constrained optimization problems. The different techniques are used in minimizing a quadrdtic approximate model of the original optimization problems in trust region. By the convergence analysis, the global convergences and local superlinear convergences of the algorithms are obtained. Finally,the implementations of the algorithms are given.  相似文献   

7.
吴芳  余懋群  龙海 《粮食储藏》2011,40(2):34-37
以谷蠹为研究对象,采用L16(45)正交组合实验和单因素梯度实验对MgCl2、dNTP、随机引物、Taq酶、模板DNA浓度和退火温度、循环次数等影响RAPD扩增的重要因素进行优化,以期建立最优的RAPD反应体系与程序。实验结果表明:各因素最适条件为:25μL PCR反应体系中,10×Buffer 2.5μL,MgCl22.5 mmol/L,dNTP0.4 mmol/L,随机引物960 pmol/L,Taq酶0.5 U,模板DNA 20ng;退火温度为37℃,循环次数为45次。在对谷蠹进行RAPD分析时,采用优化的反应条件,规范实验操作,使用同厂家同批次的试剂,实验结果就会具有很好的重复性和稳定性。  相似文献   

8.
A second law analysis is carried out on convective heat transfer in fully developed region with constant wall temperature through circular, trianglar and rectangular ducts. Besides, the entropy generation rate expression is obtained and the loss rate of available energy in convective heat transfer processes is defined as well. At the same time, the influence of initial temperature difference between fluid and wall as well as the influence of fluid friction on the loss rate of available energy is discussed. Then, the thermodynamic performances of several typical ducts are compared. Finally , the optimum initial temperature difference with the minimum loss rate of available energy is also obtained.  相似文献   

9.
The condition when forces are applied to load mechnical mornent limiter of tow-er cranes is analysed and disctissed in this paper.A lifting performance curve adapted for the me-chanical load moment limiter is also obtained.And finally,the curve drawing method is explainedthrough the practical example.  相似文献   

10.
11.
In this paper,the four-moment reliability analysis method for perfopmance function implicit structure is discussed. Discrete formulas expressed by Gauss-quadrature are presented when determine the parameter of probability density function which is established based on maximum entropy theory. The method in this paper is proposed for performance function implicit structure. Particularly, the discrete formulas used in this paper largely reduce calculating work with the same precision, so that the time-consume problem of four-moment reliability anlaysis is solved.  相似文献   

12.
This paper presents an optimization method for solving the boundary value question of a differential equation on the basis of the trial-and-error method and the optimization method. As compared with the differential method, this method has some advantages such as quiker velocity at count, higher precision(especially at the boundary points) and can be widely used.  相似文献   

13.
This paper studys the appraisal of thermal performance quality of cold storage. Analyses therom-moist perfomance of envelopes of cold storage and cheCks them with the measured data tested in site for seven cold storages, presents a optimum construction proogramme for fruit cold storage.  相似文献   

14.
15.
基于时间分辨荧光微球制备的黄曲霉毒素B1荧光定量快速检测试纸卡,通过两线及三线试纸卡灵敏度与重复性的对比,筛选出效果更优的三线试纸卡,并对三线试纸卡不同性能要求进行检测验证。结果表明,黄曲霉毒素B1三线试纸卡检出限与定量限符合要求,准确度、重复性、稳定性等均达到更优的效果,更能满足检测需求。  相似文献   

16.
A model and a heuristic algorithm for reliabilty op timi zation in generalized stochastic flow networks are proposed in this paper. The stochastic characteristic of the demands at terminal nodes is considered in the model. The algorithm proposed is powerful and can be applied to optimal planning of transmission capacity for large scale stochastic flow networks, because it can facilitate a fast location of optimal capacity expansion from the information obtained by the last iteration by making full use of the relationships of the k-weak link set and failure events set to the paramsters in generalized stochastic flow networks  相似文献   

17.
南阳彩色小麦中氨基酸含量的研究及初步评价   总被引:1,自引:0,他引:1  
高向阳  黄晓书  张斌 《粮食储藏》2007,36(4):42-45,48
研究南阳彩色小麦中氨基酸的含量水平,为该小麦系列新品种的开发利用提供科学依据,以南阳灰色、蓝色、紫色小麦为原料,以河南几种豫麦品种为对照,用高效液相色谱法对其氨基酸组成和营养品质进行了初步分析.实验结果表明:南阳彩色小麦的氨基酸含量较高,质量分数依次为普通紫色小麦15.88%,硬质紫色小麦15.63%,蓝色小麦14.84%,灰色小麦为14.35%.小麦蛋白质中氨基酸的种类齐全,紫色小麦中苏氨酸的含量较普通小麦增幅115.15%.8种必需氨基酸比例合适,组成合理,其中酪氨酸和苯丙氨酸的比例较高.经综合分析,紫色上麦的营养价值较高,建议做进一步的开发研究.  相似文献   

18.
On the basis of the mechanism of the boiling heat transfer on low finned tube, the influence of the geometric parameters of low finned tube on boiling heat transfer is synthetically analyzed and relevant criteria which affect the optimal structure of low finned tube is deduced in this paper. The boiling heat transfer experiment on low finned tube is conducted. Distilled water and R-113 are used as test fluids The experiment is performed at local atmospheric pressure. Synthesizing a large amount of experimental data, the semiempirical equations for the optimal geometric parameters of lowfinned tube are established  相似文献   

19.
20.
This paper introduces the main structure and function,the theor-etical basis and the main features of the computer aided design software system QT-SCAD for the steel structure of tower crane.The QT-SCAD is suitable for allkinds of movable or fixable tower crane with level arm which rotates above thecrane body,and has single or double hanging points.It can be used for the stre-ngth,stiffness and stability analyses of the structure,the vibrative and dynamiccalculation of mechanisms and structure,and the optimal design of the structureof tower crane or its components.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号