一种一维距离像的识别算法

随着高分辨率雷达的发展,一维距离像识别已成为雷达目标识别的重要方法之一.为了消除一维距离像的平移,将一维距离像变换到频域,提取其频谱信息作为识别特征,并依据Fisher判据,将高维特征空间数据降到一维空间,提高了算法的实时性.仿真结果表明这是一种方便有效的识别方法.     

码分无线射频识别系统空中接口协议设计及性能分析

为进一步提高无线射频识别系统单个读写器识别电子标签的速率,设计了一种将码分与统计时分技术相结合的新型无线射频识别系统的空中接口协议,并分析了系统的抗噪声性能、识别速率等主要性能指标。仿真结果表明,新型无线射频识别系统在抗噪声性能和识别速率等方面均优于基于现有国际标准ISO/IEC 18000-6C的无线射频识别系统。     

应用于雷达方位超分辨的改进Richardson-Lucy算法

方位超分辨是国内外雷达界持续探索的一项技术难题。为解决高斯噪声情况下天线低通效应造成的方位低分辨力问题,利用基于泊松噪声情况下Richardson-Lucy(RL)算法对其进行研究。针对RL算法中高斯噪声被放大出现虚假目标和RL算法收敛速度慢的缺点,提出了一种改进RL算法。该算法首先使用低通滤波去除高频段的噪声,然后利用加速RL算法进行方位超分辨。仿真结果表明：与原RL算法相比,改进RL算法能降低高斯噪声的影响,消除虚假目标;在信噪比低至0 dB时,相对于半功率波束宽度,改进RL算法的最大分辩倍数为1.8倍,与维纳逆滤波算法相比具有较强的噪声适应能力,可以应用于雷达方位超分辨。     

基于联合概率加权的高分辨雷达目标点迹处理

针对高分辨雷达在跟踪扩展目标时出现多散射点的问题,提出了一种基于联合概率加权的雷达目标点迹处理方法。首先,对信号检测出的多散射点构建其残差变量,根据判别准则进行目标点迹配对处理,剔除异常散射点;然后,同时考虑散射点位置和回波幅度信息,计算联合概率的权值,目标多散射点经概率加权融合后估计得到散射中心。仿真分析表明,该方法在高分辨雷达扩展目标点迹处理中能有效抑制杂波的干扰,目标点迹精度在距离、方位和俯仰上分别提高了20.63%、47.51%和41.03%,同时具有很好的可靠性,满足工程应用的需求。     

Return prediction and stock selection from unidentified historical data

The experimental approach was applied to test the value of historical return series in technical prediction. Return sequences were randomly drawn cross-sectionally and over time from S&P500 records and participants were asked to predict the 13th realization from 12 preceding returns. The hypothesis that predictions (nominal or real) are randomly assigned to historical sequences is rejected in permutation tests, and the best-stock portfolios by experimental predictions significantly outperform the worst-stock portfolios in joint examination of mean return and volatility. The participants dynamically adjust their predictions to the observed series and switch from momentum riding to contrarian extrapolation when recent trends get extreme. The implicit tuning of predictions to specific series captures variabilities that could not be inferred by schematic statistical forecasting.     

构筑和完善企业集团监督制约机制

企业已经有多种多样的监督，但缺乏统一的平台和力量的整合。如果不能迅速、及时、有效地整合监督资源和力量，“五不行为”导致的国有资产流失将无法遏制。要通过健全股东监督体系、组织监督体系、民主监督体系和经营者的自我监督，并用有效方式强化股东监督，构筑和完善企业监督制约机制。     

浙江外贸发展的轨迹特点与动因探析

浙江外贸增速迅猛，长期存在贸易顺差，其发展轨迹具有地域性和集群性的特点。究其原因，浙江外贸在制度安排、市场主体、交易方式和产业组织形式等方面有其独特之处，“浙江外贸现象”是民营企业追逐利润的必然结果。     

Public participation and local environmental planning: Testing factors influencing decision quality and implementation in four case studies from Germany

Public and stakeholder participation in environmental planning is often assumed to enhance effectiveness through improving the environmental quality of decisions and enhancing implementation. We draw on the literature on participatory environmental governance in order to derive key participation-related factors that are hypothesized to impact on decision quality and implementation. We then outline four cases of decision-making processes in local environmental planning in Germany, representing a variety of forms of public participation, and what we suggest can be seen as four different pathways to ‘success’ in participatory planning. The case studies, recounted on the basis of stakeholder interviews and secondary research, are subjected to a cross-case analysis in order to examine the influence of participation in each case. We consider how key participation-related factors played out across the cases, and assess both decision quality and implementation against counterfactual non-participatory, or less-participatory, scenarios. In moving beyond accounts of ‘what happened’, and considering how participation changed the order of things relative to ‘what would have happened’ under different scenarios, the research highlights how very different pathways may lead to ‘success’ in participatory environmental planning from the viewpoint of process organizers and planners sympathetic to environmental issues. We conclude that, given the significance of context and surprises, planners and process organizers must be open to different pathways to the successful conclusion of participatory planning processes.     

Has the Chinese currency been undervalued?

China's trade surplus reached a record $102 billion in 2005 while the US trade deficit of $717 billion accounted for 5.8% of US Gross Domestic Product in the same year. US policy makers claim China's currency is undervalued about 25 to 35% against the US dollar and they blame China for holding the value of the RMB weak to keep Chinese products competitive on prices in international markets. Given the unique situation in China, where the capital account is only partially convertible and the economy has been growing at an annual average rate of 10% over the last two decades, this paper empirically examines the magnitude of the exchange rate misalignment of China's RMB against the US dollar by using the Behavioral Equilibrium Exchange Rate (BEER) and Permanent Equilibrium Exchange Rate (PEER) models. Our results show that the RMB was undervalued by approximately 15% from 2002:Q2 to 2003:Q4; however, it is interesting to note that while the RMB was overvalued during 1997:Q4–2002:Q2, China experienced a huge trade surplus during that period.     

个人信用保证机制的征信制度和诉讼制度比较研究

征信体系通过建立一种声誉制度,促进人类合作、提高群体成员效用和福利。个人信用保证机制的征信制度和诉讼制度哪个成本更低、相对价值更高需要客观分析。在完全竞争的信贷市场研究场景下,声誉机制有引致合作行为的能力;扩展博弈下,诉讼制度的威胁使得借贷者施加一个高的努力程度,提高了社会总剩余。基于现代信息技术的声誉机制出现以后,存在于每个银行内部的声誉就变成了一个统一、全范围扩展的声誉机制,所以声誉制度比诉讼制度可以获得更高的社会总剩余。