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71.
论述了通过MOLDFLOW的模拟分析,预测出仪表板的原始进浇方案可能出现的成型缺陷,并验证了优化方案的可行性,从而提高了注塑产品的质量、缩短了开发周期、降低了生产成本。 相似文献
72.
电子海图平台下的航线自动设计方法 总被引:2,自引:0,他引:2
为优化舰船计划航线设计,提出了一种基于电子海图的自动设计方法.通过追踪安全等深线和处理障碍区,得到可航渡区域.在可航渡区域内,进行路径的可航渡性测试,自动搜索一条安全的最短计划航线,并根据障碍区的动态变化,实时调整和优化航线.实验结果表明,与传统的手工作业方法相比,该方法在效率、经济性、可靠性等方面都具有明显的优势. 相似文献
73.
Panel‐based stratified cluster sampling and analysis for photovoltaic outdoor measurements 下载免费PDF全文
We study a stratified multisite cluster‐sampling panel time series approach in order to analyse and evaluate the quality and reliability of produced items, motivated by the problem to sample and analyse multisite outdoor measurements from photovoltaic systems. The specific stratified sampling in spatial clusters reduces sampling costs and allows for heterogeneity as well as for the analysis of spatial correlations due to defects and damages that tend to occur in clusters. The analysis is based on weighted least squares using data‐dependent weights. We show that this does not affect consistency and asymptotic normality of the least squares estimator under the proposed sampling design under general conditions. The estimation of the relevant variance–covariance matrices is discussed in detail for various models including nested designs and random effects. The strata corresponding to damages or manufacturers are modelled via a quality feature by means of a threshold approach. The analysis of outdoor electroluminescence images shows that spatial correlations and local clusters may arise in such photovoltaic data. Further, relevant statistics such as the mean pixel intensity cannot be assumed to follow a Gaussian law. We investigate the proposed inferential tools in detail by simulations in order to assess the influence of spatial cluster correlations and serial correlations on the test's size and power. ©2016 The Authors. Applied Stochastic Models in Business and Industry published by John Wiley & Sons, Ltd. 相似文献
74.
研究5维复射影空间的完备共圆平坦K(a)ehler子流形,得到了局部结构与关于数量曲率的拼挤常数. 相似文献
75.
基于逆向工程技术实现汽车覆盖件回弹评测 总被引:1,自引:0,他引:1
针对实际冲压件提出了一种基于逆向工程技术的回弹评测方式.对实际冲压件进行激光扫描后重构出型面,根据弹性变形的特点对模型进行强制变形以找到节点的对应关系,并根据CAD模型的几何中心计算出曲面的重合点,以对应节点的距离为适应度函数利用遗传算法搜寻出最佳旋转位置,并计算出各节点的法向偏移距离作为该节点的回弹量.该方法实现了对冲压件各个部分回弹的精确评测,从而可以为模具的修整提供正确的指导. 相似文献
76.
Simulating the softness property of object is quite a challenge in virtual reality system. A novel softness display system was developed based on the principle of deformable length of elastic element control (DLEEC). In the system, the equivalent stiffness of the device is adjustable, and is inversely proportional to the third power of the deformable length of elastic beam. PD position control is employed to guarantee the accurate softness display. The softness of the virtual objects in large scale can be felt with the softness display device. Compared with other haptic devices, the device is passive and exert the react force only when the operator "actively touch" the virtual objects. The stability of the softness display system was analyzed. It was theoretical proved that the system satisfied the criteria of wide impedance range "Z-width", and the performance was superior to an active system. The experimental results were presented. 相似文献
77.
等高线图分析技术在GC/FTIR联用数据处理中的应用 总被引:1,自引:0,他引:1
钟山 《光谱学与光谱分析》1995,15(6):41-44,50
在三种高聚物的裂解大口径毛细管气相色谱-傅里叶变换红外光谱联用分析(PyWBCGC/FTIR)数据获得的基础上,介绍应用等高线图(CTD)分析技术处理色谱重叠峰,并在该分析提供的信息指导下进行红外光谱累加及差减技术,获得了重叠峰中各纯物质较好信噪比的气相红外谱图并予以定性,显著了等高线图分析技术在联用数据中的优点,充分发挥了GC/FTIR联用特有的光谱分离离度优势。 相似文献
78.
Structure of Positive Solutions of Quasilinear Elliptic Equations with Critical and Supercritical Growth 下载免费PDF全文
The structure of positive radial solutions to a class of quasilinear elliptic equations with critical and supercritical growth is precisely studied. A large solution and a small solution are obtained for the equations. It is shown that the large solution is unique, its asymptotic behaviour and flat core are also discussed. 相似文献
79.
In developing a new method to measure the phase distribution of a light wave utilizing the adaptive control of the pupil function with a liquid crystal panel, the optimization procedure for the adaptive control is shown to improve when a local algorithm is adopted. The feasibility of the proposed system is confirmed by computer simulation as well as by some basic experiments. 相似文献
80.
Huang Zhaoyong 《代数通讯》2013,41(3):1457-1464
Let Λ be a left and right Noetherian ring. For a positive integer k, we give an equivalent condition that flat dimensions of the first k terms in the minimal injective resolution of Λ are less than or equal to k. In this case we show that the subcategory consisting of k-torsionfree modules is extension closed. Moreover we prove that for a Noetherian algebra every subcategory consisting of i-torsionfree modules is extension closed for any 1 ≤ i ≤ k if and only if every subcategory consisting of i-th syzygy modules is extension closed for any 1 ≤ i ≤ k. Our results generalize the main results in Auslander and Reiten [4]. 相似文献