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1.
陈孟奇 《电信工程技术与标准化》2018,(9)
近年,各类专线业务的“大带宽、低时延、快响应”诉求愈加明显,对传送网的承载能力提出更高的要求,特别是其中N*10G 业务需求规模逐年增加, 有必要研究一套标准化的承载模式来满足业务接入的需求,以实现对业务连接的网络承载模式标准化、快速化、智能化。 相似文献
2.
Junhua Hu Xiaohong Zhang Yan Yang Yongmei Liu Xiaohong Chen 《International Transactions in Operational Research》2020,27(2):1236-1261
Nowadays, we can use different websites that help us make decisions about various aspects of our lives. However, privacy protection prevents websites from providing personalised guidelines to users. We propose a novel doctor‐ranking system (DRS) based on multi‐criteria group decision‐making (MCGDM) method to address the problems of privacy protection. The following aspects differentiate our proposed DRS model from previous works: (a) textual information reviews are used to identify user preferences and complementary criteria, (b) criteria weights are determined by term frequency inverse document frequency (TF‐IDF) instead of Delphi method or expert opinion, (c) intuitionistic fuzzy sets (IFSs) are used to replace sentiment analysis to express subjective user criteria, and (d) VIsekriterijumsko KOmpromisno Rangiranjie (VIKOR) method for MCGDM with IFSs is used to solve the doctor‐ranking problem. We apply our proposed model to datasets from Haodf.com to compare the performance of our method with that of sentiment analysis and technique for order performance by similarity to ideal solution (TOPSIS) methods. The experimental results show that our method provides accurate ranking and increases the reliability of DRS. 相似文献
3.
本文提出了目前供暖计量收费存在的若干问题,并就这些问题阐述了作者的一些看法,认为目前实施计量收费还需要做很多工作。 相似文献
4.
Yao Guoliang 《中国建设信息》2007,(3)
本文根据多联机空调系统的特性,分析了配管长度对多联机空调系统制冷量和能效比的影响,提出了合理使用多联机,提高空调系统制冷量和能效比的建议。 相似文献
5.
6.
在众多路径规划算法中,A^*算法是一种典型的最短路径规划算法,但是该算法的应用环境较为局限。为此综合复杂环境中人群密度的因素,以时间最短为准则,将最短距离路径规划问题优化为最短时间路径规划。最优路径规划算法在A^*算法的基础上,引入不同人群密度环境下的行人速度模型,将A^*算法中基于距离的评估函数改变为基于时间的评估函数。实验通过标准网格地图对144种情况进行了模拟,结果表明,相较于传统A^*算法,最优路径规划算法优先选择从周围低人群密度区域绕行到达终点,规划路径在距离上可能更长,但是花费的时间更短。 相似文献
7.
《Urban Water Journal》2013,10(5):370-378
This study conducted statistical analysis under both stationary and non-stationary climate using rainfall data measured in Seoul, South Korea. The 50 year annual maximum rainfall data were analysed with generalised extreme value distribution and Gumbel distribution. Possible rainfall changes were predicted with nonstationary forms of the two distributions, considering time variable location parameters. The current storm sewer design criteria were assessed by reflecting climate change implications and expected lifetime performance. Expected return periods were reduced to 4.67, 8.66, 19.16 and 23.53 years for the current 10 min - 5, 10, 30 and 50 years. The newly suggested design criteria of 5, 10, 30 and 50 yr return period storm events were 5.3, 12, 48 and 107 years for the 10 min duration for a 50 year lifetime expectancy. 相似文献
8.
本文研究了重金属和石油烃复合污染土壤中,腐植酸对草本植物吸收重金属的影响。结果显示:腐植酸大幅度地降低了污染土壤中可溶性和交换态重金属含量,但提高了植物可利用态重金属含量。土壤添加腐植酸后,除Ni外,重金属潜在生物有效性和可淋出性因子大于1,这表明大多数重金属对植物具有潜在的有效性。此外,腐植酸增加了铅(Pb)、铜(Cu)、镉(Cd)和镍(Ni)在供试植物幼苗和根部的积累,最高的是高羊茅幼苗,达264.7%,生物富集系数从0.30提高到1.10。芸苔根中Ni和Pb的生物富集系数也有所提高。这些研究结果表明,石油烃与重金属同时污染的情况下,加入腐植酸可以促进植物吸收重金属,但降低重金属淋失,防止地下污染。 相似文献
9.
An adaptive color similarity function suitable for image segmentation and its numerical evaluation 下载免费PDF全文
Rodolfo Alvarado‐Cervantes Edgardo M. Felipe‐Riverón Vladislav Khartchenko Oleksiy Pogrebnyak 《Color research and application》2017,42(2):156-172
In this article, we present an adaptive color similarity function defined in a modified hue‐saturation‐intensity color space, which can be used directly as a metric to obtain pixel‐wise segmentation of color images among other applications. The color information of every pixel is integrated as a unit by an adaptive similarity function thus avoiding color information scattering. As a direct application we present an efficient interactive, supervised color segmentation method with linear complexity respect to the number of pixels of the input image. The process has three steps: (1) Manual selection of few pixels in a sample of the color to be segmented. (2) Automatic generation of the so called color similarity image (CSI), which is a gray level image with all the gray level tonalities associated with the selected color. (3) Automatic threshold of the CSI to obtain the final segmentation. The proposed technique is direct, simple and computationally inexpensive. The evaluation of the efficiency of the color segmentation method is presented showing good performance in all cases of study. A comparative study is made between the behavior of the proposed method and two comparable segmentation techniques in color images using (1) the Euclidean metric of the a* and b* color channels rejecting L* and (2) a probabilistic approach on a* and b* in the CIE L*a*b* color space. Our testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. It was obtained from the results that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume in the CIE L*a*b* color space. We show that our solution improves the quality of the proposed color segmentation technique and its quick result is significant with respect to other solutions found in the literature. The method also gives a good performance in low chromaticity, gray level and low contrast images. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 156–172, 2017 相似文献
10.
Manuel Gómez‐López Maruxa García‐Quiroga Enrique Arbones‐Maciñeira Ma Lourdes Vázquez‐Odériz Ma Angeles Romero‐Rodríguez 《International Journal of Food Science & Technology》2014,49(1):107-113
Galicia (N.W. Spain) produces 60% of Spanish kiwifruit (Actinidia deliciosa) and 5–20% of these are ‘destrío’ fruits, which do not reach market size and the appropriate form. These rejected fruits can be processed into products, thus increasing their added value. The processing of kiwifruit always includes a peeling operation, which can be performed by different systems. The most suitable conditions for caustic peeling and thermal peeling were established. Then, the two peeling systems were compared with manual peeling with the aim of selecting the best system to remove the peel of the ‘destrío’ kiwifruit. The fruits, once harvested, were stored in a cold chamber at 0 °C. Before processing or marketing kiwifruits, it is necessary to remove them from storage in cold chamber and storage at room temperature. In this study, different storage times at room temperature before peeling kiwifruits were also tested. The best system for peeling the kiwifruit was thermal peeling as this system resulted in the lowest weight loss and preserved the green colour characteristic of the kiwifruit. The best time for peeling the kiwifruit was after 8 days of storage at room temperature, after being removed from the cold chamber. 相似文献