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再生改性混凝土的性能
Performance on Recycled Modified Concrete
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Hans Journal of Civil Engineering (HJCE) , 2013, DOI: 10.12677/HJCE.2013.24038
Abstract:
拆除原有的建筑物,对废弃的混凝土加以利用,既可以保护环境又关系到建筑的可持续发展。将废弃的混凝土破碎再生骨料,需要建立一套工艺方法。现就目前国内比较成熟的方法是:使用膨胀剂能够制成C50的补偿收缩再生混凝土。<br/>Demolition of existent building and reclamation of abandoned concrete thereof not only protect the environment but also relate to the sustainable development of building industry. It needs an overall technology process to break abandoned concrete into reclaimed aggregate. The method which is mature in home is that: Reclaimed C50 compensation shrinkage concrete could be made by mixing with expansion additive.
LDPC码校验矩阵回路的求解算法
LDPC Code’s Girth Calculation Algorithm
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Hans Journal of Wireless Communications (HJWC) , 2014, DOI: 10.12677/HJWC.2014.41003
Abstract: 1996LDPC(低密度奇偶校验,Low-Density Parity-Check)码是性能限与香农限仅差0.0045 dB的一种差错控制码[1],译码采用SPA(和积算法),但其性能受Tanner图中回路长度和回路数目的影响,回路的存在使译码信息重复迭代,性能下降[2]。本论文通过计算机仿真,采用Matlab元胞数组,将二元校验矩阵转换为树矩阵,实现了求解LDPC码回路的算法。
 Low-Density Parity-Check codes have advantageous performances discovered in 1996 with Shannon limit only 0.0045 dB. Decoding algorithm adopts SPA (Sum-Product Algorithm). However, girths in LDPC codes are detrimental to the code’s performance, and the existence of loops makes the decoding information iterative and the performance reduced. This paper, through computer simulation, using the Matlab cellular array, to convert the binary check matrix to tree matrix, realizes the algorithm of LDPC codes loop
HSB信息隐藏算法设计与实现
The Design and Implementation of HSB Information Hiding Algorithm
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Hans Journal of Data Mining (HJDM) , 2012, DOI: 10.12677/hjdm.2012.22002
Abstract: 本文首先介绍BMP文件结构及特点,再介绍LSB算法,针对传统LSB算法可嵌入图像大小的限制,提出了一种有损信息隐藏算法HSB(Highest Significant Bits),此算法基于24位BMP图像文件,有效的增加了嵌入图像的大小,分别对于图像型和文字型图像进行实验证明。实验编程环境为VS2008,结果证明了此算法的正确性和有效性。
This dissertation first introduces the structure and characteristic of BMP file and then the LSB algorithm. A lossy information hiding algorithm named HSB (Highest Significant Bits) is proposed in order to break the limit of the embedded image by the traditional LSB algorithm. The new algorithm is based on 24-bit BMP image and increases the size of the embedded image, which is applicable to both image and text. The development environment is VS2008 and it demonstrates the correctness and effectiveness of the new algorithm.
基于R软件分析两组专家对五个葡萄酒样品的评分数据
Analyzing the Score Data of Five Wine Samples from Two Groups of Experts Based on R Software
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, 应应
Statistics and Applications (SA) , 2014, DOI: 10.12677/SA.2014.34018
Abstract:
本文利用R软件主要讨论了两组专家对五个葡萄酒样品的评分及专家评分的合理性问题。首先,利用两个正态总体均值的假设检验评判两组专家的评分之间是否存在显著差异,从检验结果发现两组专家的评分是基本相符的,从而评比结果有一定的公平性与合理性。其次,利用均值的多重检验考察专家们对不同样品的区分度。在0.05的显著性水平下,专家们能够区分样品1与样品2、样品3、样品5,样品2与样品4,样品3与样品4。对五个样品的等级从高到低排序之后发现,专家们基本上可以区分等级相差为1的样品。但是专家们没有有效地区分出样品1与样品4(等级相差1.5),样品3与样品5(等级相差1)。然后,运用系统聚类的方法将五个样品分为优、良、差三类。最后,采用距离判别分析法,利用训练样本建立判别函数,将训练样本回代进行判别,得到专家的误判率和正确率,从而利用判别函数对新的样本进行分类。
By using R software, we discuss the evaluations of five wine samples by two groups of specialists and the rationality of the evaluations. First of all, by using the hypothesis testing of two normal population means, we judge whether there are significant score differences between two groups of specialists. The test results show consistency of scores of two groups of specialists, and thus the evaluation result has certain fairness and rationality. Secondly, by using multiple t test of the mean, we can investigate the degree of differentiation of different samples by the specialists. Under the significance level of 0.05, the specialists can separate sample 1 from samples 2, 3, and 5, samples 2 and 4, samples 3 and 4. By ordering the levels of five samples from high to low, we find that the specialists can basically distinguish samples with levels with level difference by 1. But specialists do not effectively distinguish samples 1 and 4 (level difference 1.5), samples 3 and 5 (level difference 1). Then we use the hierarchical clustering method to classify five samples to three classes: excellent, good, and bad. Finally, by using the distance discriminant analysis method, the discriminant function is established based on the training sample, then by discrimination of the training sample, we get specialists’ misjudgment rate and accurate rate, and thus we can use the discriminant function to classify the new samples.
武汉与世界城市的水景形态学对比分析
A Morphological Analysis of the Waterscape in Wuhan and Selected World Cities
 [PDF]

陈祉曈,
Geographical Science Research (GSER) , 2015, DOI: 10.12677/GSER.2015.42005
Abstract:
在“武汉2049”长期发展战略规划提出将在2049年将武汉打造成为世界城市的背景下,关注到大部分的世界城市不仅拥有较高的经济水平,同时也提供一个优越的软环境,如城市水环境,为居民营造高质量的景观与居住环境。由此采用同时期遥感影像,从水景形态出发,将武汉与其他世界城市及一部分国内一二线城市进行比较,以四项重要的量化指标水体量、水斑块、水陆混合度、水岸线描述案例城市的水景特征,具体比较了8个指数包括不同类型水体量、水斑块均匀度、最大斑块比、分离度、熵值、水岸线长度、边缘密度等。研究结果显示:武汉是一个具有中等水量的城市、城市水斑块均衡、拥有相当长的水岸线、水陆混合度非常高;湖区是武汉高水陆混合度的主要原因;武汉拥有其他城市不能比肩的极长水岸线,水岸线是其最重要的城市特征。基于此总结提出了武汉在水景形态影响下的三个重点发展策略。
In November 2013, Wuhan “Year of 2049” Long-term Development Strategic Plan put forward to build Wuhan a world city. Under this background, we notice that most of the world cities not only have a higher economic level, but also have a good soft ambient just like waterscape to provide high-quality landscape and life for the citizens just like New York and Chicago. This article compares Wuhan to some typical world cities and some influential Chinese urban areas in term of the waterscape to emphasize the uniqueness and advantage. First we chose some case cities, then an evaluation system was built to analyze the water data extracted from the remote sensing image including four important quantitative indicators which were raised to describe the characteristic of the waterscape. Detailed indexes include water area, patches number, largest patch index, Split, entropy and total water line and edge density. The results indicate that Wuhan is a city with fairly large water area; its patch size is quite suitable for creating high quality living space and waterfront. The mixing degree of the land and water is extremely high and the longest waterline is a unique advantage of it. Then longest water line is the most important water character. In the comparison you can see Wuhan is the only one who owns so many lakes which several layers of living space are easy to form. Based on the research conclusion, three key development strategies were brought forward to participate in the development process of Wuhan.
The Advanced Thinking Mode for Contemporary Editor
当代编辑应有良好的思维方式


中国科技期刊研究 , 2001,
Abstract: 科技期刊的编辑作为该媒介的组织者,其工作方式的优化是编辑始终不懈的追求,本文从时代的特点出发,阐述了当代编辑应具备的基本思维方式。
土地利用/土地覆盖变化研究重点之二:土地覆盖变化机制的直接观测与诊断模型

地理科学进展 , 1996,
Abstract: 1 导言 土地覆盖变化是全球变化的一个重要方面,然而我们对它的认识却很不足,原因有两个,一是对于土地覆盖变化的速率、地理范围和空间模式,我们尚缺乏精确的测量方法;二是在通过经验观察来进行模拟方面,我们的力量较薄弱。本焦点建立了一种实践方法,通过把经验性观察和诊断模型相结合来分析土地覆盖变化。 对土地覆盖变化的直接观察可以通过运用遥感手段来进行。在不同的时空尺度上,从大尺度的地区趋势的估测到地方尺度的复杂动态分析,遥感都是具体地进行这些测量的最有效工
土地利用结构及其驱动因子的统计分析——以榆林地区为例

地理科学进展 , 1997,
Abstract: 本文采用了典型相关分析这一经典的数理统计方法,对榆林地区土地利用结构的驱动因子进行了统计分析。通过大型社会科学统计软件包SPSS操作运行,并对统计结果进行专业分析,定量诊断出各驱动因子对该区土地利用结构分布贡献作用的大小。同时运用典型相关系数和冗余度分析,对诊断结果进行了检验
重力对物理气相沉积Zn膜生长的影响

科学通报 , 1997,
Abstract: 近年来利气相生长的方法制备高质量薄膜倍受人们重视。在地面上用气相沉积方法生长薄膜。由于重力作用人们很难精确控制传热和传质行为,从而影响薄膜质量。微重力条件,可以抑制气相传输过程中重力引起的对流,可望获得厚度均匀、表面质量好、结构完整的高质量薄膜。美国、俄国、日本、欧空局所属国等都投入相当大的人力、物力进行这一领域的研究工作。但是,空间实验昂贵,设备复杂,限制了空间实验的大量进行;进行充分的地基工作,如进行样品筛选、研究重力场效应等是十分迫切的任务。通过改变薄膜生长方向与重力场方向之间的相对取向关系来研究重力场的作用,对于指导地面及空间实验、对于探讨重力场对薄膜生长的物理本质具有重大意义。
Ag/Bi多层膜的结构研究

科学通报 , 1997,
Abstract: 多层膜一般是由交替沉积而成的两种元素组成的亚层构成,在近十几年中,由于多层膜具有独特的电、磁、光和机械等优良性能,并且合成的多层膜结构提供一个高密度界面条件以研究非平衡情况下在界面处材料的相互作用,所以使它在技术应用和基础研究领域的应用日趋广泛,在许多性能应用中人们必须考虑来自结构的影响,如果亚层的厚度都很小,在纳米数量级,在垂直多层膜的膜面方向上成一维周期结构,则这种一维周期结构将产生Bragg衍射,不过所产生的Bragg衍射峰在0°<2θ<10°范围内,一般称为调制峰,不管采用什么沉积技术,一般制备的多层膜不是非常完整的,有许多可能的非完整情况,界面粗糙度就是这种非完整情况之一,多层膜的结构主要由调制波长L(两层不同元素组成的亚层厚度之和)、亚层结构和表面粗糙度等因素来表达,目前人们对具有负混合能的多层膜系统已经进行了大量的研究工作,但对具有正混合能的多层膜系统则研究的较少.
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