发动机装配过程工艺防错技术探索

发动机是汽车的核心部件,是汽车制造商和车主最关心的问题,其运行情况直接关系到整车的质量。目前存在的主要问题是多个品种的动机混线装配,就会存在质量问题,经常出现装错、漏装等问题,遭到客户的投诉,给公司带来不利影响,还会给企业造成一定的经济防错技术损失。为了解决这些问题,提高产品质量,就需要针对复杂操作问题采取防错技术,以降低劳动强度,减轻劳动者的压力。本论文针对发动机装配过程工艺防措技术展开研究。

Modeling and Defending Passive Worms over Unstructured Peer-to-Peer Networks

Passive worms can passively propagate through embedding themselves into some sharing files, which can result in significant damage to unstructured P2P networks. To study the passive worm behaviors, this paper firstly analyzes and obtains the average delay for all peers in the whole transmitting process due to the limitation of network throughput, and then proposes a mathematical model for the propagation of passive worms over the unstructured P2P networks. The model mainly takes the effect of the network throughput into account, and applies a new healthy files dissemination-based defense strategy according to the file popularity which follows the Zipf distribution. The simulation results show that the propagation of passive worms is mainly governed by the number of hops, initially infected files and uninfected files. The larger the number of hops, the more rapidly the passive worms propagate. If the number of the initially infected files is increased by the attackers, the propagation speed of passive worms increases obviously. A larger size of the uninfected file results in a better attack performance. However, the number of files generated by passive worms is not an important factor governing the propagation of passive worms. The effectiveness of healthy files dissemination strategy is verified. This model can provide a guideline in the control of unstructured P2P networks as well as passive worm defense.

Molecular Therapy and Prevention of Liver Diseases

Molecular analyses have become an integral part of biomedical research as well as clinical medicine. The definition of the genetic basis of many human diseases has led to a better understanding of their pathogenesis and has in addition offered new perspectives for their diagnosis, therapy and prevention. Genetically, human diseases can be classified as hereditary monogenic, acquired monogenic and polygenic diseases. Based on this classification, gene therapy is based on six concepts: (1) gene repair, (2) gene substitution, (3) cell therapy, (4) block of gene expression or function, (5) DNA vaccination and (6) gene augmentation. While major advances have been made in all areas of gene therapy during the last years, various delivery, targeting and safety issues need to be addressed before these strategies will enter clinical practice. Nevertheless, gene therapy will eventually become part of the management of patients with various liver diseases, complementing or replacing existing therapeutic and preventive strategies.

Outburst control technology for rapid excavation in severe outburst coal

The advantages and disadvantages of various outburst prevention measures inheading face were analyzed.The mechanism of outburst prevention about hydraulic extrusionmeasure was studied, the technological parameters were introduced, and the effectof outburst prevention was investigated.The in-situ experimental results show that thehydraulic extrusion measures are applied in serious outburst mine, not only the stress ofstimulate outburst is eliminated effectively but also the gas in coal seam is released efficiently,the measures get obvious effect on coal and gas outburst prevention, and theroadway driving speed is increased by 1.5 times, implementing a safe and rapid excavation.

Approaches for Preventing the Male Sterility Fluctuation of Photo-thermo-sensitive Genie Male Sterile Lines in Rice

The male sterility fluctuation of photo-thermo-sensitive genie male sterile(P(T) CMS Jlines induced by low air temperature is a key problem troubling the application of two-line system hybrid rice.The paper suggests to solve this problem by the breeding approaches,i.e,developing low sterile critical temperature P(T)GMS lines,herbicide resistant restorer lines,herbicide sensitive P(T)GMS lines and tetracydine-conditioned P(T)GMS lines to ensure the hybrid purity;and by the hybrid seed production techniques,i.e,taking the correct procedure of foundation seed production,the suitable district and season for hybrid seed production and the deep irrigation method against cold weather in high summer.

Debris-flow Treatment:The Integration of Botanical and Geotechnical Methods

Due to special topographical, geological and meteorological conditions, debris flows occur frequently and result in heavy losses of lives and properties in mountainous areas, which become a great threaten to the sustainable development of regional economy and society in western China. At present, debris-flow prevention has performed well in many mountainous countries and has made headway in early warning, disaster mitigation by structural engineering methods, and risk analysis and management. In this paper, debris-flow prevention techniques have been introduced from the aspects of botanical methods, geotechnical engineering methods, and synthetic prevention system based on the above two methods. In addition, the treatment system of multilevel runoff and unconsolidated soil in the catchment with a chain of ＂slope-gully-valley＂ is set up in consideration of sediment load of main rivers, incorporation of slope improvement and gully retention, as well as micro-site factors for matching species with the site. Furthermore, attentions should be paid to the mechanism and technical details of vegetation measures for debris-flow prevention, as well as effective incorporation between botanical method and geotechnical method.