Experimental investigation on carbon steel micro-rod machining by LS-WEDT

This article proposed for the first time the method of the low-speed wire electrical discharge turning (LS-WEDT) combined with the multiple cutting strategy to fabricate carbon steel micro-rods. First, the rotating apparatus submerged in working fluid is designed and manufactured to enable the low-speed wire electrical discharge machine to generate cylindrical geometries. Besides, material removal rate, surface roughness, and machining precision of the micro-rod manufactured by the LS-WEDT are, respectively, investigated. Moreover, the surface microstructure and surface chemical reaction of micro-rods are characterized using scanning electron microscopy and energy-dispersive spectroscopy analysis. Experimental results display that the micro-rod of 70?µm diameter and 1000?µm length can be successfully fabricated. More importantly, the mean absolute diameter deviation of the micro-rod fabricated by LS-WEDT is 0.65?µm and the surface roughness is 0.53?µm, which identified the high machining precision and good surface quality of the micro-rod.     

Efficient estimation of a semiparametric dynamic copula model

A new semiparametric dynamic copula model is proposed where the marginals are specified as parametric GARCH-type processes, and the dependence parameter of the copula is allowed to change over time in a nonparametric way. A straightforward two-stage estimation method is given by local maximum likelihood for the dependence parameter, conditional on consistent first stage estimates of the marginals. First, the properties of the estimator are characterized in terms of bias and variance and the bandwidth selection problem is discussed. The proposed estimator attains the semiparametric efficiency bound and its superiority is demonstrated through simulations. Finally, the wide applicability of the model in financial time series is illustrated, and it is compared with traditional models based on conditional correlations.     

Inverse data envelopment analysis model to preserve relative efficiency values: The case of variable returns to scale

This paper studies the inverse Data Envelopment Analysis (inverse DEA) for the case of variable returns to scale (inverse BCC). The developed inverse BCC model can preserve relative efficiency values of all decision making units (DMUs) in a new production possibility set composing of all current DMUs and a perturbed DMU with new input and output values. We consider the inverse BCC model for a resource allocation problem, where increases of some outputs and decreases of the other outputs of the considered DMU can be taken into account simultaneously. The inverse BCC problem is in the form of a multi-objective nonlinear programming model (MONLP), which is not easy to solve. We propose a linear programming model, which gives a Pareto-efficient solution to the inverse BCC problem. However, there exists at least an optimal solution to the proposed model if and only if the new output vector is in the set of current production possibility set. The proposed approach is illustrated via a case study of a motorcycle-part company.     

RFID-initiated workflow control to facilitate patient safety and utilization efficiency in operation theater

Objective

To control the workflow for surgical patients, we in-cooperate radio-frequency identification (RFID) technology to develop a Patient Advancement Monitoring System (PAMS) in operation theater.

Methods

The web-based PAMS is designed to monitor the whole workflow for the handling of surgical patients. The system integrates multiple data entry ports Across the multi-functional surgical teams. Data are entered into the system through RFID, bar code, palm digital assistance (PDA), ultra-mobile personal computer (UMPC), or traditional keyboard at designated checkpoints. Active radio-frequency identification (RFID) tag can initiate data demonstration on the computer screens upon a patient's arrival at any particular checkpoint along the advancement pathway.

Results

The PAMS can manage the progress of operations, patient localization, identity verification, and peri-operative care. The workflow monitoring provides caregivers’ instant information sharing to enhance management efficiency.

Conclusion

RFID-initiate surgical workflow control is valuable to meet the safety, quality, efficiency requirements in operation theater.     

一种基于双线性对的群密钥管理方案

现有群密钥管理方案大都基于GDH(Group key Management Based on Diffi}Hellman)密钥交互协议,该协议限制了子树规模。针对这一问题,提出一种基于双线性对的群密胡管理方案(13PGKM, Group Kcy Managcmcnt based on I3ifinear Pairing),该方案在保证安全的前提下可扩大密钥树中子树的规模,以支持更大规模的网络,同时可使计算操作减少一半,以提高群密钥管理操作的效率。     

机载激光水下目标探测中GPS的应用

在机载激光对水下目标探测技术中,如何快速有效的搜索目标并得到目标的精确位置信息是其中的重要内容,为此,研究提出了将全球卫星定位系统（GPS）应用于机载激光水下目标探测的方法,将GPS信号作为探测信号的一个参数,与探测信号同时进行实时的传输与存储。基于此方法可以实现多机协同的高效搜索,并可对每个探测信号实现精确定位,使探测信息在脱线分析中也能得到充分利用。针对上述方法进行了仿真试验,证明了其可行性。     

CIO：源头遏制垃圾邮件的新方法

分析了垃圾邮件的起源和目前泛滥的严峻形势,讨论了几种主流的垃圾邮件处理技术,指出了这些技术的缺陷,根据垃圾邮件的本质,提出了能够从源头上遏制这类邮件的CIO方法。     

基于DEA模型的我国上市商业银行效率研究

本文采用了数据包络分析（DEA）方法研究我国上市商业银行的经济效率,结果表明：我国上市商业银行的全要素生产率（TFP）和技术效率都偏低,国有四大行的整体技术效率也明显低于股份制商业银行,我国银行业的经营管理与技术水平稳定性较差。最后文章提出几点关于银行业发展的建议。     

浅谈江汉油田劳动用工对策

目前,江汉油田劳动用工存在着结构性超员与结构性缺员并存,新增一线技能操作人员文化程度低、技能水平低、劳动效率其他用工人员身份不明确、缺乏归属感,技能操作队伍不稳定,其他用工和正式职工没有实行同工同酬的问题。要改善劳动用工现状,必须积极补充新的劳动力资源;强化劳动定员定额管理;开展多种形式培训,提高技能人才队伍整体素质;认真贯彻执行《劳动合同法》,确保技能操作队伍稳定;创新用人机制,遵循现代企业发展规律。