基于keystone变换的噪声调频连续波雷达高速目标探测

针对目标高速运动导致严重多普勒色散的问题,提出基于keystone变换的距离徙动校正方法。根据噪声调频连续波无周期性的特点,对回波信号采用等间隔重叠分段法进行频域相关处理。结合快速离散时间尺度变换算法,能够实现高效的长时间相参积累。无需先验知识,能处理多目标场景。通过仿真实验验证了该方法的有效性,并与传统时域相关法进行了比较和分析。当目标未出现距离徙动时,该文方法和时域相关法对目标输出信噪比的提升效果基本一致。当目标出现距离徙动后,时域相关法的输出信噪比迅速下降,恶化程度与徙动严重程度成正比,而该文方法经距离徙动校正后的输出信噪比则基本不受目标速度的影响,且仍随积累时间的增加而增大。     

渤海辽东湾旅游资源整合开发研究

以渤海辽东湾为研究对象,探查梳理了旅游资源的空间分布;解析旅游资源结构和特点发现其各类国家级旅游资源在辽宁省内具有一定的比较优势,辽东湾两岸旅游资源虽特色互补但旅游发展却东强西弱;为改变辽东湾旅游发展问题提出旅游全方位开发策略,在巩固提升原有品牌旅游的基础上,借助无景点旅游发展盘活羡余旅游资源,基于非高铁出游进行圈层式整合开发,基于高铁出游进行点轴式旅游整合开发.     

新乡市工业发展效率与城市转型绩效评价

从工业发展效率和城市综合发展两个方面评价新乡市近年来的转型发展效果.基于数据包络分析的Malmquist指数法,对新乡市工业部门投入产出效率进行测算分析,发现新乡市工业发展态势良好,绝大部分行业依靠技术进步和技术效率的提高取得了生产率的改善,逐步走向集约型的经济增长道路;构建新乡市城市转型绩效评价指标体系,综合考虑经济指标、社会指标、资源指标和环境指标,运用熵权法对其城市转型效果进行测度分析,结果表明新乡市城市转型运行情况良好,经济指数、环境指数取得了较大的进步,而资源指数和社会指数进步较小.     

Research progress in ZnO single-crystal: growth,scientific understanding,and device applications

Zinc oxide, a wide band-gap semiconductor, has shown extensive potential applications in high-efficiency semiconductor photoelectronic devices, semiconductor photocatalysis, and diluted magnetic semiconductors. Due to the undisputed lattice integrity, ZnO single crystals are essential for the fabrication of high-quality ZnO-based photoelectronic devices, and also believed to be ideal research subjects for understanding the underlying mechanisms of semiconductor photocatalysis and diluted magnetic semiconductors. This review, which is organized in two main parts, introduces the recent progress in growth, basic characterization, and device development of ZnO single crystals, and some related works in our group. The first part begins from the growth of ZnO single crystal, and summarizes the fundamental and applied investigations based on ZnO single crystals. These works are composed of the fabrication of homoepitaxial ZnO-based photoelectronic devices, the research on the photocatalysis mechanism, and dilute magnetic mechanism. The second part describes the fabrication of highly thermostable n-type ZnO with high mobility and high electron concentration through intentional doping. More importantly, in this part, a conceptual approach for fabricating highly thermostable p-type ZnO materials with high mobility through an integrated three-step treatment is proposed on the basis of the preliminary research.     

城市表层土壤重金属污染分析研究

基于某城市城区土壤地质环境调查得到的城市不同功能区、不同海拔位置的表层土壤中8种主要重金属浓度为样本,评价了该城区内不同区域重金属的污染程度;通过数据分析了重金属污染的主要原因;基于重金属污染物的传播特征,建立了确定污染源的位置的数学模型;为了更好地研究城市地质环境的演变模式,指出应收集更多信息以及利用这些信息如何建立模型解决问题.     

公共财政视角下的西藏新型城镇化发展探析

新型城镇化发展是人类社会实现区域统筹协调发展、构建和谐社会的必经阶段,也是西藏实现城乡一体化、逐步走出贫困落后的重要环节之一。公共财政以其自身所具有的职能属性,在新型城镇化发展进程中具有巨大的促进作用。文章分析了公共财政在新型城镇化发展进程中的职能定位,结合西藏具体区情,探讨了西藏在新型城镇化发展中面临的问题,并基于公共财政的视角提出西藏新型城镇化发展的对策建议。     

Temporal dynamics in social trust prediction

Inferring unknown social trust relations attracts increasing attention in recent years. However, social trust, as a social concept, is intrinsically dynamic, and exploiting temporal dynamics provides challenges and opportunities for social trust prediction. In this paper, we investigate social trust prediction by exploiting temporal dynamics. In particular, we model the dynamics of user preferences in two principled ways. The first one focuses on temporal weight; the second one targets temporal smoothness. By incorporating these two types of temporal dynamics into traditional matrix factorization based social trust prediction model, two extended social trust prediction models are proposed and the cor- responding algorithms to solve the models are designed too. We conduct experiments on a real-world dataset and the results dem- onstrate the effectiveness of our proposed new models. Further experiments are also conducted to understand the importance of temporal dynamics in social trust prediction.     

光催化共振荧光法测定水中痕量铀

在磷酸介质中,UO_2~(+2)能催化过氧化氢氧化曙红Y(EY),导致体系的共振荧光强度降低,据此建立了光催化共振荧光法检测水中痕量铀的新方法.实验发现,曙红Y最大的共振荧光波长530 nm.实验中发现,共振荧光降低值ΔF与铀(Ⅵ)浓度在0.4~15.0 ug/L范围内线性关系良好,可以应用标准曲线法测定环境样品中的铀.RSD小于2.77%,加标回收率为95%~103.8%.测定环境水样中铀(Ⅵ),结果良好.     

混酸法制备水溶性沥青的实验条件研究

以中温煤焦油沥青为原料,采用浓硫酸和浓硝酸混酸氧化,碱溶酸沉法提纯制备易溶于碱性水溶液的水溶性沥青。以水溶性沥青收率及红外光谱峰强度为指标考察了氧化温度、反应时间、混酸比、液料比等因素影响。实验结果表明:中温煤焦油沥青在氧化温度40℃,反应时间5 h,混酸比(浓硫酸和浓硝酸的体积比)7:3,料液比1 g:20 m L,得到116%产率的水溶性沥青。     

“水质控制”在瓯江梯级混合型水库调度中的应用

介绍了浙江电网水库调度应用中瓯江梯级混合型水库水质控制功能植入发电调度中的原理及方法.不同的调度权限对水库调度有不同的目标要求,该方法对存在天然水力联系的梯级水库间进行联调水质,为协调不同调度权限间水库调度需求提供依据,对今后有不同侧重需求的水库调度系统项目建设具有重要的参考价值.