旋转法处理平面度误差测量数据的计算机辅助分析

平面度误差测量中常采用旋转法处理数据,使之符合最小条件,从而计算出平面度误差。但手工处理过程复杂,工作量大。使用我们自主开发的计算机辅助分析软件,不仅可以提高运算速度,而且可以通过CAD图形分析模块的分析,为生产加工提出指导性意见。     

Microsoft Excel sensitivity analysis for linear and stochastic program feed formulation

Sensitivity analysis is a part of mathematical programming solutions and is used in making nutritional and economic decisions for a given feed formulation problem. The terms shadow price and reduced cost are familiar linear program (LP) terms to feed formulators. Because of the nonlinear nature of stochastic programming (SP), different methods and terminology are used to define shadow prices and reduced costs. The Lagrange multiplier is used instead of shadow price to describe marginal value of nutrients. Reduced gradient is used instead of reduced cost to describe the price at which ingredients not used in the formulation would be included in the solution. A spreadsheet feed problem was set up with 11 ingredients and 11 constraints. The LP and SP solutions were determined using the Excel Solver algorithm. Two problems compared LP and SP solutions at 50 and 69% probabilities for the protein constraint. All other constraints were held at a 50% probability. Results for the 50% probability comparison showed that the feed formulations, as expected, were the same for both LP and SP. Wheat was not included in the solution. The LP reduced cost and the SP reduced gradient for unused wheat were equivalent. The LP shadow prices and the SP Lagrange multipliers were equivalent. Results for the 69% probability problem showed a difference in the formulated rations. The LP reduced cost was $34.25 and the SP reduced cost was $34.52, showing the respective amounts that the cost of wheat would have to be reduced to be included in the solution. The shadow price and the Lagrange multiplier were $2.73 and $2.71, respectively, for the amount of increase in diet cost that could be expected by a unit of change in the protein requirement. Some differences in precision were noted with the results. A caveat is that, because of nonlinearity, sensitivity analysis for SP is valid only for the single point of the optimal solution.     

腰轮流量计在油品计量中的误差分析

通过对腰轮流量计在制造过程中的误差分析,以及在使用过程中泄漏量、油品粘度、温度、油质等因素对测量精确度的影响分析,提出了消除和减少计量误差的办法,保证流量计在所要求的计量精度下运行,尽量减少经济损失.     

CAPP设计中误差模型的建立

提出了一个在CAPP设计中用于合理制定各工序公差的误差模型。该模型以误差统计和误差传递思想为基础,根据各工序的工艺能力及中间工序加工误差对最终工序加工误差影响的大小来合理制定各工序公差。     

试论家具零部件的标准化

论述了我国家具行业存在的问题 ,就标准化的客观要求和家具零部件标准化的内容做了阐述 ,并分析了实现家具零部件标准化与互换性的条件 ,提出家具零部件标准化应遵循的原则     

TMJ-A人造板弹性模量无损检测显示机的误差因素分析

人造板无损检测是在线检测结构用人造板力学性能、保证产品质量的重要环节。本文介绍了弹性模量无损检测设备的功能和工作原理 ,从测试方法、机械系统、控制系统几个方面入手 ,分析了测试误差的形成原因及影响因素 ,为进一步提高人造板无损检测设备的测试精度和可靠性提供依据     

利用温敏致死性状专养雄蚕的研究进展

伴性赤蚁（sch)具有催青期高温干燥敏感性，用30℃、相对湿度60％条件催青时雌卵孵化率很低，雄卵正常孵化。利用sch品种作父本与普通蚕品种杂交，其F1代的蚕卵仍具有高温催青敏感性，这是控制桑蚕性别实现雄蚕饲养的一条新途径。     

浅谈建设项目经济评价方法不确定性分析

本文简要分析不确定性因素对经济评价指标的影响,和不确定性分析的几种方法,确定项目在经济上的可靠性。     

Application of Artificial Neural Network in Elastic Internal Force Analysis of Two Way Slab

In this paper, the Artificial Neural Network (ANN) is applied to the internal force analysis of structure. After introducing the model and algorithm of back-propagation network, a trained BP network of three layers is used to calculate the maximum of elastic moment of middle span of two-way slab. In order to enhance the generalized capability of network, the modified value of weight should be regarded as convergence standard and in order to accelerate the learning process without vibration, the method of adding momentum coefficient is adopted. The analysis program of BP network is carried out with the software of Matlab. The result demonstrates that application of ANN in structure analysis is feasible.     

Genetic Control of Temperature-Sensitivity of Cytoplasmic Male Sterility (cms) in Chives (Allium schoenoprasum L.)

In earlier experiments with chives (Allium schoenoprasum L.) temperature-sensitive and temperature-insensitive cms plants could be selected. To obtain information about the site and nature of the genetic factor(s) responsible for the temperature sensitivity of the cms, temperature-insensitive and temperauire-sensitive cms plants were crossed with maintainers as well as with one another. In the progenies each genotype was cloned into two clone members, and these were examined concerning their male sterility under normal (20 °C/14 °C, day/night) as well as under constantly high temperatures (24 °C/ 24 °C). The results indicate that the temperature-sensitivity of the cms is controlled by a dominant nuclear gene “T”. This acts like a restorer gene at high temperatures and is ineffective at normal temperatures. Accordingly, important conclusions can be drawn with regard to the selection of temperature-insensitive cms-lines as well as to the propagation of the cmi-lines. The results are discussed in connection with the mitochondrial polypeptides probably responsible for the formation of the cms.