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1.
设S1,S2 ,… ,SN 是Rn 上的N个仿射压缩映射 ,若Rn 的紧子集E满足E UNi =1 Si(E) ,则称E为子自仿射集 .作者在一定条件下得到了子自仿射集E的Hausdorff维数 .  相似文献   

2.
数字高程模型数据小波压缩算法   总被引:8,自引:0,他引:8       下载免费PDF全文
针对海量DEM数据的存储和传输的问题,设计出一种高效的DEM数据的小波压缩算法。基于提升理论提出了一种包含自由变量t的紧支撑小波构造方法;通过选取合适的小波滤波器系数,基于提升的整数小波变换只需要整数加法、整数乘法和移位实现,运算速度快,便于硬件实现;选取参数t=1的整数9-7小波变换,其运算量接近整数5-3小波,但DEM数据压缩质量接近浮点的CDF9-7小波。实验证明该压缩算法对DEM数据有极佳的压缩效果,在保持地形形状和起伏特征的前提下,DEM数据可以压缩4096倍,PSNR>34DB。  相似文献   

3.
针对直接利用时域波形识别中医脉象准确率低的问题,提出了一种基于 AR 模型和 K-L 变换的脉象模糊聚类方法。首先对脉象样本作8阶 AR 模型拟合,模型系数构成样本的特征集,其次采用 K-L 变换对特征集进行了压缩,最后利用 F-PFSR(Fuzzy Pseudo F-Statistic Ratio)聚类法对临床实测的40例脉象样本进行了聚类分析。实验结果表明,该方法的聚类准确率平均为85%。  相似文献   

4.
本文讨论一般工程材料液压自紧管自紧及机械加工后的残余应力计算问题。本文中,将材料单向拉伸——压缩试验中的Bauschinger效应线性化;以塑性区中的切向应变近似代替相当应变,求解发生反向屈服时的残余应力。进而分析了机械加工对残余应力的影响。  相似文献   

5.
针对FDR编码算法对1编码效率低的弊端,提出了能同时对0和1编码的改进FDR编码算法,采用基于有限状态机的解码电路设计解码器,利用Golomb编码、FDR编码和改进FDR编码算法,分别对相同与不同长度的测试集进行压缩。实验结果表明,改进FDR编码算法要优于Golomb编码与FDR编码,且对SOC测试数据的压缩是有效的。  相似文献   

6.
本文利用 Michael 连续选择定理与 F.E Browder 次连续(S)_+型映射度理论相结合的方法,构造了带紧扰动的1.s.c.集值(S)_+型映射的拓扑度,并讨论了作为其应用的不动点与值域问题.  相似文献   

7.
研究了由保形压缩映射产生的一类递归集的分形性质,得到了该类集合的Hausdorff维数.  相似文献   

8.
基于粗集的神经网络在目标类型识别中的研究   总被引:1,自引:0,他引:1  
为克服传统的目标类型识别方法的不足,提出将粗集和神经网络紧耦合建立新的识别模型,即经过识别信息预处理、样本数据粗集方法简化、神经网络学习训练及待识信息网络识别等步骤,充分融合了粗集强大的规则提取能力和神经网络优良的分类能力。实验表明,该模型减少了识别的主观因素,简化了神经网络结构,提高了运算速度。  相似文献   

9.
给出了严格集压缩场的拓扑度在非球域上的度为零的结果,改进了孙经先1987年相应的结果。  相似文献   

10.
采用行列双向压缩的数据处理策略,提出了一种基于主成分分析与模糊C-均值聚类算法的入侵检测样本数据压缩方法。该方法首先采用主成分分析法对数据冗余特征进行压缩,然后采用模糊C-均值聚类算法对冗余样本进行压缩,由此可挖掘入侵检测样本数据中的关键特征和关键样本。通过KDD CUP99数据集测试证明:数据双向压缩可减少入侵检测分类器的计算量,进而可提高其实时检测性能和检测推断的准确性。  相似文献   

11.
Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).  相似文献   

12.
A change order is frequently initiated by either the supplier or the buyer, especially when the contract is long‐term or when the contractual design is complex. In response to a change order, the buyer can enter a bargaining process to negotiate a new price. If the bargaining fails, she pays a cancellation fee (or penalty) and opens an auction. We call this process the sequential bargaining‐auction (BA). At the time of bargaining, the buyer is uncertain as to whether the bargained price is set to her advantage; indeed, she might, or might not, obtain a better price in the new auction. To overcome these difficulties, we propose a new change‐order‐handling mechanism by which the buyer has an option to change the contractual supplier after bargaining ends with a bargained price. We call this the option mechanism. By this mechanism, the privilege of selling products or services is transferred to a new supplier if the buyer exercises the option. To exercise the option, the buyer pays a prespecified cash payment, which we call the switch price, to the original supplier. If the option is not exercised, the bargained price remains in effect. When a switch price is proposed by the buyer, the supplier decides whether or not to accept it. If the supplier accepts it, the buyer opens an auction. The option is exercised when there is a winner in the auction. This article shows how, under the option mechanism, the optimal switch price and the optimal reserve price are determined. Compared to the sequential BA, both the buyer and the supplier benefit. Additionally, the option mechanism coordinates the supply chain consisting of the two parties. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 248–265, 2015  相似文献   

13.
The conflict between the rebel group, the Polisario Front, and the Kingdom of Morocco is nearing its 43rd year. Though under-reported, the conflict itself garners attention for the resilience – some would say tenacity – of the ethnically Sahrawi Polisario Front. Despite shifting regional and international politics and the nearly 150,000 Sahrawi refugees waiting in nearby Algerian camps, the rebel group has survived. What explains its resilience? This article uses Bourdieu’s ‘forms of capital’ to understand the Polisario Front’s persistence. Based on field research in Algeria, Western Sahara, and the United States, it finds that social, cultural, symbolic, and economic capital may provide an explanation.  相似文献   

14.
新疆伊斯兰教建筑装饰艺术的特征是以一种特殊的造型、形式、色彩、材质,多种多样的装饰技巧以及独有的审美特征体现出来的。是新疆伊斯兰教建筑文化体系中取得最高成就的一部分,是集实用功能、审美功能、认识教育功能于一体的艺术形式,蕴涵着地域环境、民情风俗、审美价值等丰富的内容,呈现出浓郁的风格特点。这些装饰艺术的特征,影响着人们的情绪,净化着穆斯林们的心灵,给观赏者以建筑装饰艺术的造型、色彩、纹饰的美感,获得审美的愉悦。  相似文献   

15.
新疆兵团(以下简称"兵团")体育文化的形成植根于军队,发展于屯垦戍边事业,在我国民族体育文化中具有独树一帜的特征和价值;在60年的发展历程中,一直以兵团精神为精神支柱和发展动力,为促进兵团社会政治、经济、文化等事业发展,维护新疆社会稳定发挥了重要作用。近年来,兵团体育文化与城市化快速发展不相适应,仍然保留着"单位体制"、"行政运行"的局面,严重阻碍了兵团体育文化多元化、特色化、社会化的发展,因此,在兵团城市化背景下,体育文化体制、体育物质文化和体育文化内容必须走创新之路,才有发展的生机和活力。  相似文献   

16.
This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.  相似文献   

17.
本文以作者参加研制的柴油机检测与诊断系统为对象,在分析柴油机故障机理及特点的基础上,详细论述了检测与诊断系统的组织与结构,检测参数的选择与取舍,信号数据的采集与处理和系统故障诊断等方面的问题。文章着重论述了转速的测量及其在柴油机检测与诊断系统中的应用,柴油机高压油路的检测与诊断,DSP系统软件的开发及其在柴油机表面振动诊断中的应用。  相似文献   

18.
本文在总结学前教育专业实际钢琴技能课教学的基础上,通过对钢琴技能课的教学反思,从提高对钢琴技能课学习的认识,加强学前教育专业钢琴技能学习的角度出发,提倡立足传统教学,勇于教学创新,开拓思路,探索灵活多样的授课形式,整合教学资源,研究新教材、探索新教法,立足于学前教育的专业特点,注重学前教育专业键盘技能的实际运用,并建立科学、可行的学前专业技能考核标准,从而促进学前专业音乐技能课的发展。  相似文献   

19.
结合营区规划实例,以军事行政区主轴线为研究对象,在分析现阶段军事行政区主轴线空间节点设计中比较集中存在的几个问题基础上,提出了构建军事行政区主轴线空间节点秩序及应遵循的一般原则,并以常见的入口区—广场区—办公区—训练区的轴线构成为例,对军事行政区主轴线各空间节点的秩序构建进行了空间、尺度及人性化等设计方法的探讨,为推动营区规划的正规化、现代化建设提供一些思路和方法。  相似文献   

20.
In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.  相似文献   

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