陆基链式超短波监测网布站仿真测算

无线电用户移动性的增加对低干扰的电磁环境提出了更高的要求。陆基链式超短波监测网可以为高速移动的无线电用户提供这种保障。该网络在用户移动路线周边布站,及时发现判定路径周边的干扰隐患,可以提升保障覆盖范围。通过设计仿真测算方法和计算公式,在设定的仿真条件下计算出直线线路条件下陆基链式监测站的理论布站距离为10~25 km,为今后该网的设计提供了参考依据。     

弹群组网应用与关键技术

随着弹药技术及网络技术的快速发展,弹群组网作战系统作为未来作战体系中的重要角色受到了世界各国的高度关注。简要概述了国外弹群组网作战系统的发展趋势,并对弹群组网作战能力进行了定性分析;在此基础上,建立了基于多层面、多子网、同构与异构并存、有中心与无中心网络的弹群组网混合体系架构,并对其功能及特点进行了详细分析;对弹群组网作战系统亟待解决的关键技术进行了梳理,为其工程应用提供了理论参考。     

Common Institutional Ownership and Earnings Management*

This study examines the relation between earnings management and block ownership of same‐industry peer firms by a common set of institutional investors (common institutional ownership). This relation is important given the tremendous growth of common institutional ownership and the significant influence of blockholders on financial reporting. We hypothesize that common institutional ownership mitigates earnings management by enhancing institutions' monitoring efficiency and by encouraging institutions to internalize the negative externality of a firm's earnings management on peer firms' investments. Consistent with our hypothesis, we find that higher common institutional ownership is related to less earnings management. Analyses of a quasi‐natural experiment based on financial institution mergers show that this negative relation is unlikely to be driven by the endogeneity of common institutional ownership. Cross‐sectional tests provide evidence that the negative relation is stronger among firms for which common institutional ownership is likely to generate a greater reduction in institutions' information acquisition and processing costs, and among firms whose severe financial misstatements are more likely to distort co‐owned peer firms' investments, supporting both mechanisms underlying our hypothesis. Our findings inform the ongoing debate on the costs and benefits of common institutional ownership by highlighting an important benefit: the enhanced monitoring of financial reporting.     

基于高分辨率遥感影像的福州城区建筑用地变化动态监测

利用2006年DMC和2008年UCD两期高分辨率的正射航空遥感影像,对福州市城区建筑用地变化情况进行监测。提取并分析了福州市城区建筑用地变化的特征和规律。结果表明,近两年仓山区建筑用地面积变化最大,增长速度最快;福州市城区建筑用地变化的最大特点是新建建筑用地面积明显大于改扩建建筑用地面积;福州市中心城区逐渐往仓山区方向扩展。     

土地综合整治质量监测研究

通过研究土地整治质量的监测内容、评价指标及监测技术,为不断推动我国土地整治质量监测的发展提供借鉴。监测内容包括土地整治工程质量、土壤质量、生态环境质量、景观维护以及土地整治可持续5个方面,并总结了相应的监测指标和监测手段,监测技术主要有常规的测定仪器、实验室分析方法、3S技术、探地雷达和无线传感器网络等。我国土地整治质量监测应该向着"土地数量、质量并重管理和生态管护"的方向发展,传统技术手段结合新的科技将促进我国土地整治质量监测不断走向深入。     

环境监测仪器的采购、验收及管理

随着科学技术的发展,环境监测仪器越来越先进,给仪器的采购、验收、管理及使用带来了巨大的考验。规范认真的采购和验收才能为今后的仪器管理和使用打下良好的基础。本文讨论了仪器采购、验收、管理工作中值得注意的问题。     

四川省车用汽油安全风险监测与分析

为了解四川省车用汽油质量安全现状,并为加强车用汽油质量安全监管提供依据,国家石油天然气产品质量监督检验中心在全省范围内采集3种标号共200个批次的车用汽油样品进行监测。结果表明:90号车用汽油质量安全的风险较高,93号车用汽油质量安全的风险较高,97号车用汽油质量存在风险,四川省流通领域的车用汽油质量现状并不乐观,消费者的用油安全存在一定风险。     

Concurrent sourcing,governance mechanisms,and performance outcomes in industrial value chains

We examine transaction governance in the context of concurrent sourcing, where a manufacturer relies on sourcing from external suppliers and in‐house production simultaneously. Our focus is on (1) a buyer's use of particular safeguards or governance mechanisms vis‐à‐vis an external supplier and (2) how the effects of these mechanisms on various performance outcomes are influenced by the joint presence of an internal manufacturing branch. We conduct two studies in the apparel industry and show that performance outcomes are a joint function of (1) the individual governance mechanisms that are deployed in a particular relationship and (2) the larger sourcing context (concurrent or singular). Copyright © 2013 John Wiley & Sons, Ltd.     

微型桩结合土钉墙在基坑支护工程中的应用

结合工程实践,阐述微型桩结合土钉墙在基坑支护工程中的应用,为基坑支护设计工作者提供一定的参考意见,对同类工程实施具有借鉴指导作用。