242 research outputs found
Visual Analysis of Literature Review of Phase Space Reconstruction
为探究相空间重构理论至今为止的发展历程及前景,特以CiteSpaceⅢ可视化引文分析软件为工具,通过文献计量学研究方法,对来自于Web of; Science平台的与phase space reconstruction相关1; 500篇文献按时间分布、空间分布、引文及作者分布的情况进行了汇总整理,并以图、表的形式展现。根据关键词和共现图及关键词时区图,重点考察了相空间重; 构理论的研究热点及趋势。研究表明,该理论的发文量逐年增加且势头强劲;在工程、技术领域的应用越发广泛;与多种算法相结合,可提高非线性系统的分析与预; 测精度。The primary object of the paper is to reveal the development process and; prospect of phase space reconstruction theory. The technique applied is; referred as CiteSpace Ⅲ, a visualized analysis software for citation.; The research method of literature metrology was used to classify the; fifteen hundred papers from the Web of Science platform related with; phase space reconstruction into different priorities according to time; distribution, spatial distribution, citation and author distribution.; All results were displayed in figures and tables. The hot spot and trend; of phase space reconstruction were discussed based on the keywords; co-occurrence graph and keywords time zone map. The study showed that; the amount of the publications on the theory increased year by year; harply, and it has been applied more widely in the field of engineering; and technology. Combined with a variety of algorithms, the accuracy of; the analysis and prediction of nonlinear systems can be improved.国家自然科学基
Theoretical Study on the Organic Functionalization of the Silicon Surfaces
Abstract Chemical modification of semiconductor surface is of great interest because of its potential applications. A marriage of organics and semiconductors is expected to result in new device applications, including molecular electronics, sensors, nanotechnology and so on. Due to the limited resolution of experimental techniques, however, it is becoming apparent that the interplay between ex...学位:理学硕士院系专业:化学化工学院化学系_物理化学(含化学物理)学号:20032511
Design and Preparation of Pd-UiO MOFs Catalyst and Performance for Catalytic Tandem Hydrogenation and Esterification of Carbon Dioxide to Ethyl Formate
随着现代工业的蓬勃发展,全球二氧化碳(CO2)排放量已经达到每年数百亿吨。CO2作为主要的温室气体,其大量排放导致的全球气候变暖正得到全世界的普遍关注。同时,CO2也是一种无毒、不可燃、地球上蕴藏量最为丰富且廉价易得的C1资源。将CO2转化为有价值的燃料或化学品不仅可以减少CO2的排放减缓温室效应,而且还可以变废为宝,因此得到许多科学家的重视,是现代科学研究的热点之一。 在众多的CO2转化产物中,甲酸乙酯(HCOOEt)作为一种重要化工品,在食品、医药、香料、有机合成中有着广泛应用。根据已经报道的文献研究,由CO2加氢合成HCOOEt需要经过两步反应。第一步:CO2加氢生成甲酸中间体,其中金...Global carbon dioxide (CO2) emissions have reached several ten billions of tons per year with the development of industry. CO2 as a main greenhouse gas is being widespread concern around the world. However, CO2 is also a non-toxic, non-flammable, abundant, and available C1 resources.So, the conversion of carbon dioxide into the valuable chemicals is one of the hot pots in modern scientific researc...学位:理学硕士院系专业:化学化工学院_物理化学学号:2052014115158
A reliability study of students' rating on teachers' teaching on the basis of the generalization theory
通过计算概化系数和可靠性指数来评价医科院校教师教学水平学生评价量表的信度。结果发现:教学内容、教学方法、教学态度、教学效果领域信度较好,教学组织领域信度尚可,若要修改,可考虑增加教学组织的条目数,减少其他领域的条目数。Objective: This study uses the generalization theory to check the reliability of students' rating on teachers' teaching on the basis of the generalization theory. While the findings indicate good reliability in the areas of teaching content,method,attitude and outcome,the reliability of teaching arrangement indicates changes need to be made probably by increasing questions in this survey item.昆明医科大学教研教改项目(2013JY-Y39
中国内陸農村の出稼ぎと所得分布 : 1999年四川省農家調査の個票データを用いて
In this paper, we analyze econometrically the effect of migration on income differences in rural China, by a case study using the micro data of Sichuan rural household survey in 1999, conducted by Research Center for Rural Economy (RCRE). We compare the distributions of the predictive income if migrants have been working in agriculture and the actual one, reveal that migrant\u27s earnings contribute to the improvement of income, and that most of migrants are produced from the low-income class
新兴市场国家货币汇率“害怕浮动”现象分析——以新制度经济学为视角
在实行浮动汇率制的新兴市场国家中,普遍存在着“害怕浮动”的现象。新制度经济学为这一现象提供了一个很好的分析视角。汇率制度的供求与均衡关系说明“害怕浮动”现象的存在具有一定的必然性,它是政府和微观市场主体通过多次博弈所作出的选择。根据制度变迁理论,汇率制度的选择也是一个动态的变迁过程,具有历史阶段性。因此,新兴市场国家汇率制度的选择不是一成不变的,这种“害怕浮动”的现象是非常态的。新兴市场国家应根据本国的实际情况选择符合本国经济发展的汇率制度
新型纳米结构电极体系的界面结构和性能
1 背景 具有重要应用功能的新体系和新研究方法,是当代电化学与其他学科实现交叉及电化学本身发展的二个主要研究方向。“九五”国家自然科学基金重点项目“新型纳米结构电极体系的界面结构和性能”,正是遵循电化学的主要方向,以新型材料或结构、尤其是纳米结构制备电极(包括表面增强光学电极、过渡金属薄膜和表面合金电极、纳米结构半导体膜电极、电活性表面团簇电极);利用电化学现
Treatment of algae bloom water using ·OH based on conventional drinking water process
我国水体的富营养化日益严重,水源地出现季节性藻类爆发现象,严重威胁饮用水安全。以厦门市莲坂水厂各工艺段出水为研究对象,采用大气压强电离放电产生羟; 基自由基(·OH),分别对水源水、混凝沉淀出水、砂滤出水进行处理,处理时间为4.5 s。当注入总氧化剂浓度为1.8 mg·; L~(-1)时,高藻浓度从25.3*10~4 cells · mL~(-1)降到800 cells ·; mL~(-1);对混凝沉淀出水注入总氧化剂0.6 mg· L~(-1)、砂滤出水注入0.2 mg·; L~(-1)时,藻细胞都未检出;·OH处理后CODMn、TOC及UV254均有明显降低,砂滤出水三卤甲烷小于8; mug·L~(-1);检测的各项指标均达到国家《生活饮用水卫生标准》(GB; 5479-2006)。因此,·OH可快速有效安全地杀灭高藻,为我国高藻水源地饮用水卫生安全保障提供技术支撑。Due to the increasing eutrophication in China, harmful algae blooms; often occur in water body periodically, which poses serious threats to; drinking water safety. Using a strong ionization discharge technology at; atmosphere pressure, ·OH was used to remove algae bloom. Other; conventional process such as coagulation, sedimentation and sand; filtration were applied respectively in the Lianban Water Plant in; Xiamen (China). The total reaction time required in the three water; processes was only 4.5 s. When the total reactive oxidant (TRO); concentration injected to algae bloom water was 1.8 mg·L~(-1), the algae; content was decreased by ·OH from 25.3*10~4 cells·mL~(-1) to 800; cells·mL~(-1). When the TRO that was injected into coagulation,; sedimentation and sand filtration water achieved 0.6 mg·L~(-1) and 0.2; mg·L~(-1), respectively, the algae contents were not detected (ND) in; treated effluents. At the same time, water quality in CODMn, TOC and; UV254 were decreased and the disinfection by-products(DBPs) such as,; trihalomethanes (THMs) concentration was lower than 8 mug·L~(-1) in; treated effluents. The treated effluent, resulting from this technology,; met the requirement of the National Drinking Water Standards (GB; 5479-2006). Therefore, ·OH was effective and safe to remove freshwater; algae without further treatment being required.国家科技支撑计划项目; 国家重大科研仪器研制项目; 科技部创新人才推进计划重点领域创新团
基于角膜地形图的泪膜视频预处理
在基于角膜地形图的泪膜稳定性评估中,针对眼动、睫毛反射和背景干扰,本文提出了一种泪膜视频的预处理算法。首先,利用索贝尔算子(Sobel operator)进行模糊图像检测,然后对灰度图像进行形态学开运算以获取环状图样凸显的目标图像,再通过霍夫圆检测以及快速傅里叶变换提取目标图像的环状图样频率,依据环状图样频率对目标图像进行带通滤波。最后,二值化及形态学闭运算用于确定环状图样区域。本文从数据库中随机选取10段泪膜视频,应用上述算法逐帧进行泪膜图像处理。实验结果表明,该算法有效地去除了视频序列中的无效图像,并实现了环状图样的定位,为后续泪膜稳定性的评估奠定了基础
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