构建广电网络骨干光缆监测管理系统

主要介绍光缆线路自动监测系统的工作原理、组成结构和功能，针对广电行业的实际业务需求，比较了不同类型监测方法的优势和应用于广电城域骨干网光缆线路自动监测系统的解决方案，最后指出构建广电网络骨干光缆监测管理系统的前瞻性与扩展性。     

一种ZigBee网络的设计与实现

集成了微电子技术、网络技术和传感器技术的无线传感器网络被认为是21世纪最重要的技术之一。本文基于Freescale公司的一站式解决方案，采用MC13192作为RF射频模块，MC9S08GT60和CF5213分别作为网络终端节点和网络协调者的主控MCU，设计实现了一种符合ZigBee规范的星型网络。     

Defining a test coverage criterion for model-level testing of FBD programs

ContextThe Programmable Logic Controller (PLC) is being integrated into the automation and control of computer systems in safety–critical domains at an increasing rate. Thoroughly testing such software to ensure safety is crucial. Function Block Diagram (FBD) is a popular data-flow programming language for PLC. Current practice often involves translating an FBD program into an equivalent C program for testing. Little research has been conducted on coverage of direct testing a data-flow program, such as an FBD program, at the model level. There are no commonly accepted structural test coverage criteria for data-flow programs. The objective of this study is to develop effective structural test coverage criterion for testing model-level FBD programs. The proposed testing scheme can be used to detect mutation errors at the logical function level.ObjectiveThe purpose of this study is to design a new test coverage criterion that can directly test FBD programs and effectively detect logical function mutation errors.MethodA complete test set for each function and function block in an FBD program are defined. Moreover, this method augments the data-flow path concept with a sensitivity check to avoid fault masking and effectively detect logical function mutation errors.ResultsPreliminary experiments show that this test coverage criterion is comprehensive and effective for error detection.ConclusionThe proposed coverage criterion is general and can be applied to real cases to improve the quality of data-flow program design.     

基于单片机控制的自动循迹停车系统

为解决一些住宅小区停车位或私家车库距离住宅楼较远、自驾车停车不方便问题,提出了利用单片机MC9S12XS128使小车从给定的起始位置自动循迹到达预期车库或停车位的系统设计方案。单片机MC9S12XS128利用PID算法对电机和舵机进行控制,摄像头传感器进行道路信息采集。该系统经测试达到了预定目标,实现了自动循迹停车功能。     

碱金属盐化合物的抗氧作用机理

利用差示扫描量热法评价全氟丁酸钠在酯类油中的抗氧性能，试验表明，全氟丁酸钠与对对二异辛基二苯胺具有良好的抗氧协同作用利用质量色谱分析油品氧化前后ＤＯＤＰＡ的变化，以确定其抗氧机理。     

聚醚改性铸型尼龙的研究

介绍了聚醚改性铸型尼龙的制备方法，以聚醚和异氰酸酯为原料合成预聚体活化剂在该活化剂存在下引发己内酰胺阴离子聚合，聚体韧性被显著改善。讨论了各各绎制备过程的影响，并测试了制品性能与预聚体用量的关系，当预体用量为聚合体重的８％时，材料缺口冲击强度最高。     

Accurate and precise determination of isotopic ratios by MC‐ICP‐MS: A review

For many decades the accurate and precise determination of isotope ratios has remained a very strong interest to many researchers due to its important applications in earth, environmental, biological, archeological, and medical sciences. Traditionally, thermal ionization mass spectrometry (TIMS) has been the technique of choice for achieving the highest accuracy and precision. However, recent developments in multi‐collector inductively coupled plasma mass spectrometry (MC‐ICP‐MS) have brought a new dimension to this field. In addition to its simple and robust sample introduction, high sample throughput, and high mass resolution, the flat‐topped peaks generated by this technique provide for accurate and precise determination of isotope ratios with precision reaching 0.001%, comparable to that achieved with TIMS. These features, in combination with the ability of the ICP source to ionize nearly all elements in the periodic table, have resulted in an increased use of MC‐ICP‐MS for such measurements in various sample matrices. To determine accurate and precise isotope ratios with MC‐ICP‐MS, utmost care must be exercised during sample preparation, optimization of the instrument, and mass bias corrections. Unfortunately, there are inconsistencies and errors evident in many MC‐ICP‐MS publications, including errors in mass bias correction models. This review examines “state‐of‐the‐art” methodologies presented in the literature for achievement of precise and accurate determinations of isotope ratios by MC‐ICP‐MS. Some general rules for such accurate and precise measurements are suggested, and calculations of combined uncertainty of the data using a few common mass bias correction models are outlined. © 2009 Crown in the right of Canada. Published by Wiley Periodicals, Inc., Mass Spec Rev 28:990–1011, 2009     

An improved algorithm for searching all minimal cuts in modified networks

A modified network is an updated network after inserting a branch string (a special path) between two nodes in the original network. Modifications are common for network expansion or reinforcement evaluation and planning. The problem of searching all minimal cuts (MCs) in a modified network is discussed and solved in this study. The existing best-known methods for solving this problem either needed extensive comparison and verification or failed to solve some special but important cases. Therefore, a more efficient, intuitive and generalized method for searching all MCs without an extensive research procedure is proposed. In this study, we first develop an intuitive algorithm based upon the reformation of all MCs in the original network to search for all MCs in a modified network. Next, the correctness of the proposed algorithm will be analyzed and proven. The computational complexity of the proposed algorithm is analyzed and compared with the existing best-known methods. Finally, two examples illustrate how all MCs are generated in a modified network using the information of all of the MCs in the corresponding original network.