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因子分析-Shrinkage法在投资组合中的理论分析及应用
Theoretical Analysis and Application on Factor Analysis-Shrinkage Method to Portfolio
 [PDF]

, 李裕梅
Hans Journal of Data Mining (HJDM) , 2015, DOI: 10.12677/HJDM.2015.53007
Abstract:
在不允许卖空的投资组合中,投资者往往希望通过投资组合模型得到最优投资组合以达到收益最大且风险最小的目标。本文对马科维茨模型以及重抽样和马科维茨模型相结合的模型进行了研究,但由于投资对象的总体分布不明确,用重抽样方法来估计总体分布可能会高估。Shrinkage法的应用缩减了估计量的方差。基于Shrinkage法及因子分析的思想,本文提出因子分析- Shrinkage法进一步优化估计量。用R软件对股票数据进行了实例分析与验证。
In the portfolio with no short sales, investors usually want to get the optimal portfolio model in order to achieve maximum benefits and minimum risk. In this paper, we research the Markowitz model and the combination model of resampling and Markowitz model. However, due to the dis-tribution of investment targets is not clear, the resampling method may overestimate the distri-bution of population. Then the application of shrinkage method has improved the variance of es-timation. Based on shrinkage method and factor analysis, factor analysis-shrinkage method is proposed to further optimize the estimation. Experimental results using the real data of stocks and R software verify the analysis factor-shrinkage method.
基于复杂网络的图像特征提取及多特征融合方案探究
Image Feature Extraction Based on Complex Network and Multi-Feature Fusion Schemes Exploration in CBIR
 [PDF]

高剂斌, 李裕梅,
Journal of Image and Signal Processing (JISP) , 2015, DOI: 10.12677/JISP.2015.44012
Abstract:
图像形状特征的提取是图像检索中重要的研究内容,本文提出一种基于复杂网络模型的图像形状特征提取方法。提取图像的SIFT关键点,在此基础上进行分块处理并逐一在每个子图上面构建复杂网络初始模型,利用最小生成树分解的方法对网络进行动态演化,提取不同子图不同时刻下的网络特征作为形状特征。本文将形状特征与颜色特征、纹理特征进行融合,通过实验比较,说明此融合方案在CBIR应用中确实具有优势。
Image shape feature’s extraction is an important research content in content-based image retrieval, and an image shape feature extraction method by using complex network model is proposed in this paper. First, SIFT keypoints of an image are extracted, and then the image is divided into blocks such that the initial complex network model can be built in each block respectively. After that, minimum spanning tree decomposition method is used for the network’s dynamic evolution, and the network features at different moments in different blocks are extracted as the image’s shape features. Furthermore, the shape features are combined with the color and texture features and a kind of fusion feature is obtained. By experiment results comparison, it shows that the fusion feature does have advantages in CBIR.
不同水分条件下追施氮肥对小麦生物量及氮素利用的影响
,王志强,林同保
麦类作物学报 , 2010, DOI: 10.7606/j.issn.1009-1041.2010.06.022
Abstract: 为了解不同水分条件下追施氮肥对小麦生物量及氮素利用的效应,以洛旱6号和豫农202为材料,采用盆栽方法,研究了不同水分下追氮量对小麦生物量及氮素吸收、积累和分配的影响。结果表明,在全生育期正常供水(维持土壤相对重量含水量在80%~85%)和控水(维持土壤相对重量含水量在50%~55%)条件下,追氮分别增加和降低了小麦地上部的生物量、氮素累积量、籽粒产量和蛋白质产量。在正常供水下拔节期追施尿素0.08g·kg-1土处理的小麦氮吸收效率最高,控水下不追氮处理的小麦氮吸收效率最高。正常供水和控水下洛旱6号均以拔节期追施尿素0.08g·kg-1土处理的氮收获指数、营养器官中的氮素转移量、转移率和贡献率最高;豫农202正常供水下拔节期追施尿素0.16g·kg-1土处理的氮收获指数、营养器官中的氮素转移量、转移率和贡献率最高,控水下追氮减少了营养器官中氮素的转移量,降低了营养器官中氮素的转移率和贡献率。以上结果说明,正常供水下追氮可增加小麦地上部生物量,提高小麦对氮素的吸收和利用能力,控水条件下小麦不宜追施氮肥。
局部二值模式方法综述及研究展望
An Overview and Research Perspective of Local Binary Pattern
 [PDF]

, 李裕梅
Journal of Image and Signal Processing (JISP) , 2016, DOI: 10.12677/JISP.2016.53016
Abstract:
局部二值模式(Local binary pattern, LBP)是一种像素层的局部特征,编码了中心像素与周围像素之间的相对强度值。由于其理论简单、计算高效,具有较高的特征辨别力和较低的计算复杂度,因此在纹理分类、人脸识别和表情检测等计算机视觉领域得到了广泛的应用,进而提出了许多LBP扩展方法,在辨别性、鲁棒性和计算效率方面有了很大提高。鉴于LBP的理论意义和使用价值,为使研究者对LBP有一个更为全面的认识和了解,便于深入研究,在前面综述文献的基础上进一步对LBP及其扩展模式进行综述,归纳了LBP改进模式的结构和LBP在不同领域中的具体应用,分析了基本LBP方法及其扩展方法结构和其优缺点,在辨别性、低维性、不变性方面与局部描述符进行了对比,总结了LBP扩展模式的应用领域。最后指出LBP扩展模式有待继续完善和发展的研究方向。
Local Binary Pattern (LBP) is a local feature on pixel level, which encodes the relative strength among the center pixel and the surrounding pixels. Because of its simple principle, high computational efficiency and feature discrimination, and low computational complexity, it has been popular in the computer vision field, such as in texture analysis field, face recognition field, expression detection field, and so on. Moreover, a number of extended methods about LBP, which are greatly improved in discrimination, robustness, and computational efficiency, are proposed. In view of the theoretical and practical value of LBP, in order to make the researcher have more comprehensive understanding and further study about LBP, this paper overviews LBP and its extended, and summarizes the specific application in different fields, and analyses the structure, as well as advantages and disadvantages. Then, some comparisons are done between LBP and other local descriptors in the aspect of identification, low dimension and invariance, and some conclusions are done about the application field of the extended LBP models. Finally, the future research directions of the extended LBP models are proposed.
2,4,6-三硝基-1,3,5-苯三酚钠盐的比热容(英)
李玲,同来,建国,孙翠
含能材料 , 2007,
Abstract: 用差示扫描量热法(DSC)测定了含能材料2,4,6-三硝基-1,3,5-苯三酚(TNPG)、一取代(Na1TNPG)、二取代(Na2TNPG)、三取代钠盐(Na3TNPG)定压下的连续比热容,计算了在50~100℃温度范围内每间隔5℃的焓差值和熵变值。从实验得出的比热容与温度的关系为:Cp(J·g-1·℃-1)=a+bT+cT2+dT3,TNPG取代钠盐例外d=0。有关误差分析表明,该测试方法是有效的,并可用于其它含能材料的比热容的测量。另外,实验相关系数接近1,表明这些化合物的比热容呈现很好的规律性。
三硝基均苯三酚钾盐的热力学研究
李玲,同来,建国,孙翠
含能材料 , 2008,
Abstract: 用差示扫描量热法(DSC)测定了含能材料2,4,6-三硝基-1,3,5-苯三酚一取代(K1TNPG),二取代(K2TNPG)及三取代钾盐(K3TNPG)定压下的连续比热容,计算了在50~100℃温度范围内每间隔5℃的焓差值和熵变值。用最小二乘法进行数据处理,得出的比热容(Cp)与温度(T)的关系为:Cp=a+bT+cT2,K1TNPG,K2TNPGandK3TNPG的线性相关系数分别为0.987,0.999和0.993。
澳门中药的管理(续完)
,昊任,
中国中医药信息杂志 , 1997,
Abstract: 6监察为实施该现行之法律,我们部门(药物事物处)需要对药房、进出口及批发商号进行经常性的检查。这些检查是由药物事物处的稽查组执行的,该稽查组由至少2人组成,其中的组长通常为1名药剂师。
澳门中药的管理
,昊任,
中国中医药信息杂志 , 1997,
Abstract: 由于历史原因,造成了澳门与内地中医药学发展的差异,尤其中药管理方面,有其自身的特点。而加强对中药的管理,其目的在于①确保澳门市民使用到安全、有效、高质量的传统药物,及提高使用传统药物的合理性;②制定准则,加强进口、出口及批发商、中药房的运作;③改良传统医师发牌资格的标准及制定有关专业守则。为了加强对澳门中药管理的了解,有利于澳门与内地行业间的交流与合作,本刊特别约请赵慧娜博士、张昊任药剂师、张悌中医师,对澳门有关中药之管理规定作了详细介绍。由于篇幅较长,特分两期连续刊出。
Difference in seedlings ammonium assimilation of wheat cultivars with different drought resistance under osmotic stress
渗透胁迫下不同抗旱性小麦幼苗氨同化差异

,王志强,崔国金,林同保
应用生态学报 , 2009,
Abstract: Taking wheat cultivars drought-resistant Luohan-6 and drought-sensitive Zhoumai-18 as test objects, their seedlings ammonium assimilation enzyme activities and related parameters were determined under osmotic stress. The plant biomass had an obvious decrease under osmotic stress, with a larger decrement for Zhoumai-18 than Luohan-6. Osmotic stress increased the plant ammonium content, especially for Zhoumai-18. The glutamine synthetase (GS) activity varied with wheat cultivars. For Luohan-6, the GS activity increased significantly under low osmotic stress but decreased under high osmotic stress; while for Zhoumai-18, the GS activity decreased with increasing osmotic stress. The NADH-dependent glut amate dehydrogenase (NADH-GDH) increased with increasing osmotic stress, with a marked increment under low osmotic stress for Zhoumai-18, and under high osmotic stress for Luohan-6. The NAD+-dependent glutamate dehydrogenase (NAD+-GDH) and NADP-dependent isocitrate dehydrogenase (NADP-ICDH) activities also increased with increasing osmotic stress, with a greater increment of NAD+-GDH activity for Zhoumai-18, and of NADP-ICDH activity for Luohan-6. It was suggested that the increased drought resistance of wheat plants could be related to the incre ased ammonium assimilation resulted from the enhanced GS and NADH-GDH activities under low and high osmotic stress, respectively.
牧区草地承包经营权流转及其对牧民生计的影响?——以内蒙古草原牧区为例
引弟,,
草业科学 , 2010,
Abstract: ?牧区草地承包经营权流转,是伴随草原新三牧政策(休牧、禁牧、划区轮牧)实施、畜牧业增长方式转型、牧区产业结构调整、牧区剩余劳动力转移等过程集中出现,又事关牧区民生与构建和谐新牧区的一个崭新的重要研究命题。本研究阐明内蒙古牧区草地承包经营权流转现状与特征,指出伴随草地流转出现租赁期短、草畜平衡对草地流转限制等问题以及牧区草地流转动因与东中部土地流转不同、草地类型流转程度不同的特征。畜产品是牧民主要收入来源,草地流转价格低影响牧民增收、加大牧区剩余劳动力转移风险。在牧区调研的基础上,提出建立与完善草地承包经营权流转机制的政策建议。
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