控制通风网络中单向回路影响程度的方法探讨

通风网络中有单向回路存在时，其节点风量平衡定律和回路阻力平衡定律仍然成立，但寻找通路本身在内的一切基于通路概念的算法都将失效，如网络调节通路法、自然分风算法中计算机自动赋风量初始值通路法、网络极值流独立通路法、角联结构判别通路法、网络简化通路法等。文中主要对控制通风网络中单向回路影响程度的方法进行探讨。     

燃油油品对电喷柴油机的影响及应对措施

随着电喷柴油机在国内工程机械上使用量的增多,因燃油油品问题而造成的柴油机故障越来越多.从电喷柴油机原理、国内外油品标准以及施工环境等角度分析其产生原因,并从工程机械使用和设计等角度提出一些应对差油品燃油的实用性措施.     

Virtual Network Mapping Through Locality-aware Topological Potential and Influence Node Ranking

Efficiently mapping multiple independent Virtual networks （VNs） over a common infrastructure sub- strate is a challenging problem on cloud computing plat- forms and large-scale future Internet testbeds. Inspired by the idea of data fields, we apply a topological poten- tial function to node ranking and propose an algorithm called Locality-aware node topological potential ranking （LNTPR）, which can precisely and efficiently reflect the relative importance of nodes. Using LNTPR and the con- cept of locality awareness, we develop the Locality-aware influence choosing node （LICN） algorithm based on a node influence model that considers the mutual influence be- tween a mapped node and its candidate mapping nodes. LNTPR and LICN improve the integration of node and link mapping. Simulation results demonstrate that the proposed algorithms exhibit good performance in deter- mining revenue, acceptance ratio, and revenue/cost ratio.     

心肌断层显像采集和处理中的若干影响因素分析

总结了６年来我院应用ＳＯＰＨＹＤＳ７型ＳＰＥＣＴ行心肌断层显像５５００余例的临床工作经验,分析了在图像采集过程中开始采集时间,断层体位及在图像处理中本底扣除,心肌以外放射性的干扰等因素对图像质量的影响,提出了如何避免和克服这些因素的建议。     

浅论油液质量对机械设备运转的影响

通过分析润滑油、液压油的质量对设备运转的影响，提出了使用润滑油、液压油的几点建议。     

CO2对钢结构的腐蚀及其控制方法

在对我国现有几个油田油管腐蚀资料进行分析研究的基础上,总结了当前的CO2对石油套管钢的腐蚀研究现状,介绍了CO2的腐蚀类型和机理,列举了CO2腐蚀的影响因素,并且提出了几种国内外常见的相应配套防腐工艺技术措施,最后指出了CO2腐蚀的研究方向与发展趋势。     

Estimating the uncertainty in the estimated mean area under the ROC curve of a classifier

This article considers the problem of binary classification and its assessment in a distribution-free approach. We estimate the area under the ROC curve (a more general performance metric than the error rate) of a classifier using a bootstrap-based estimator. We then use the method of the influence function to estimate the uncertainty of that estimate from the very same bootstrap samples. Monte Carlo trials show that small-sample estimates can be obtained with little bias.     

An accuracy improvement for balancing crankshafts

Due to measurement errors, the final accuracy of rotor balancing may not be satisfied. This study is based on a modified influence coefficient method associated with multi-plane technique for the improvement of accuracy in balancing crankshafts. This method extends the conventional influence coefficient method, in which two trial masses in one balancing plane are employed, to one utilizing three trial masses in one plane. On the basis of three trial runs, the balancing accuracy can then be improved by the optimization of influence coefficient matrices resulting from the minimization of measurement errors. The feasibility of this modified approach is carried out by the verification of accuracy improvement in experiments, balancing two crankshafts.     

钻井液润滑剂对录井资料的影响因素分析

现场钻井过程中,钻井液中加入润滑剂后,使现场综合录井受到一定的影响。本文通过现有的分析方法,对其进行分析、判别、解释,从而为综合解释排除了影响因素,提供了真实可信的数据。     

车刀安装高度对加工误差的影响

在数控车床外圆车削中，当车刀刀尖安装高度不在工件中心水平面上时，将会引起径向进刀误差，从而产生车削直径误差。文章给出了刀尖安装高度ｈ对车削台阶工件直径影响值δ的计算公式。