用和谐社会思想指导企业安全治防工作

随着我国经济的发展,企业内部治安防范工作在企业发展中的作用越来越突出。本文在对安全防治工作重要性进行分析的基础上,简要概述了我国企业安全保卫工作中存在的普遍性问题,并由此对企业实施安全保卫工作的有效途径进行探讨,以期能为企业安全防治工作的实施提供借鉴,让安全防治工作真正起到为企业的生产经营保驾护航的作用。

Study on multi-component combustible gas explosive characteristics of high gas mine

Studied on multi-component combustible gas,methane mainly,explosion char- acteristics of high gas mine,obtained the rules of gas explosive limit that influenced by environment temperature,pressure,concentration of oxygen,other combustible gas,coal dust,energy of fire source,and the inert gas,proposed a new method of divide gas explo- sive triangle partition,and gave new partition linear equations.The gas explosive triangle and its new partition has important directive significance in distinguishing if the fire area has a gas explosion when sealing or opening fire area,or fire extinguishing in sealed fire area,and judging if there will be a gas explosion or other trend while fire extinguishing with inert gas.

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.

Postpartum intrauterine device contraception: A review

AIM： To review the safety （infection, perforation） and efficacy （expulsion, continuation rates, pregnancy） of intrauterine device （IUD） insertion in the postpartum period. METHODS： MEDLINE, PubMed and Google Scholar were searched for randomized controlled trials and prospective cohort studies of IUD insertions at different times during the postpartum period. Time of insertion during the postpartum period was documented speci-fically, immediate post placenta period （within 10 min）, early post placenta period （10 min to 72 h）, and de-layed/interval period （greater than 6 wk）. Other study variables included mode of delivery, vaginal vs cesarean, manual vs use of ring forceps to insert the IUD. RESULTS： IUD insertion in the immediate postpartum （within 10 min of placental delivery）, early postpartum （10 min up to 72 h） and Interval/Delayed （6 wk onward） were found to be safe and effcacious. Expulsion rates were found to be highest in the immediate postpartum groups ranging from 14% to 27%. Immediate post placental insertion found to have expulsion rates that ranged from 3.6% to 16.2%. Expulsion rate was significantly higher after insertion following vaginal vs cesarean delivery. The rates of infection, perforation and unplanned pregnancy following postpartum IUD insertion are low. Method of insertion such as with ring forceps, by hand, or another placement method unique to the type of IUD did not show any signifcant difference in expulsion rates. Uterine perforations are highest in the delayed/interval IUD insertion groups.Breastfeeding duration and infant development are not affected by delayed/interval insertion of the non-hormonal （copper） IUD or the Levonorgestrel IUD. Timing of the Levonorgestrel IUD insertion may affect breastfeeding. CONCLUSION： IUD insertion is safe and efficacious during the immediate postpartum, early postpartum and delayed postpartum periods. Expulsion rates are highest after vaginal delivery and when inserted during the immediate postpartum period. IUD associated infection rates were not increased by insertion during the postpartum period over interval insertion rates. There is no evidence that breastfeeding is negatively affected by postpartum insertion of copper or hormone-secreting IUD. Although perforation rates were higher when inserted after lactation was initiated. Randomized controlled trials are needed to further elucidate the consequence of lactation on postpartum insertion. Despite the concerns regarding expulsion, perforation and breastfeeding, current evidence indicates that a favorable risk beneft ratio in support of postpartum IUD insertion. This may be particularly relevant for women for whom barriers exist in achieving desired pregnancy spacing.

Memory Safety Based on Probabilistic Memory Allocation

Some unsafe languages,like C and C++,let programmers maximize performance but are vulnerable to memory errors which can lead to program crashes and unpredictable behavior.Aiming to solve the problem,traditional memory allocating strategy is improved and a new probabilistic memory allocation technology is presented.By combining random memory allocating algorithm and virtual memory,memory errors are avoided in all probability during software executing.By replacing default memory allocator to manage allocation of heap memory,buffer overflows and dangling pointers are prevented.Experiments show it is better than Diehard of the following aspects:memory errors prevention,performance in memory allocation set and ability of controlling working set.So probabilistic memory allocation is a valid memory errors prevention technology and it can tolerate memory errors and provide probabilistic memory safety effectively.