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Search Results: 1 - 10 of 305509 matches for " 王珺? "
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含缺陷钢丝多道次拉拔模拟及工艺参数优化

力学与实践 , 2009, DOI: 10.6052/1000-0879-2008-067
Abstract: 利用有限元软件ABAQUS建立了含缺陷热轧盘条多道次拉拔的分析模型,研究了道次压缩率、模具顶角和裂纹长度对拉丝安全性的影响,以减少断丝率为目标探讨道次压缩率和模具顶角的最佳配合方式.研究结果表明模具顶角相同时,COD值和$J$积分值均随着裂纹尺寸的增加而增大;裂纹长度一定时,最佳入线直径随着模具顶角的增加而增大;最佳模具顶角应在4°-8°之间.利用有限元方法和断裂力学理论模拟含缺陷的热轧盘条经过多道次拉丝成型的过程,建立了钢丝经过多道次拉拔模具发生拉拔变形的分析模型,用模拟方法重点研究了道次压缩率、模具顶角以及裂纹长度对拉丝安全性的影响,以减少断丝率为目标探讨道次压缩率和模具顶角的最佳配合方式;研究结果表明模具顶角相同时,随着裂纹尺寸的增加,J积分值随之增大;裂纹长度一定时,随着模具顶角的增加,入线直径的条件最佳值也在增大;最佳模具顶角的范围应在4°-8°之间。在拉拔前应对线材进行无损探伤从而控制裂纹长度,提高线材使用率和成品质量。研究结果对进一步优化拉丝工艺参数和改进成品PC钢绞线质量提供了有价值的理论指导。
翼茧形藻的培养条件

海洋渔业 , 2012,
Abstract:
人工培养条件下环境因子对微小小环藻生长的影响

海洋渔业 , 2013,
Abstract:
生态和营养条件对日本星杆藻生长的影响
 
海洋渔业 , 2014,
Abstract:
社会资本与生产方式对集群演进的影响——一个关于企业集群的分类与演进框架的讨论与应用

社会学研究 , 2004,
Abstract: 无
基于广义线性混合模型的电信客户流失预测研究
A Study of Telecom Customer Loss Prediction Based on Generalized Linear Mixed Models
 [PDF]

, 费宇, 潘建新
Statistics and Applications (SA) , 2013, DOI: 10.12677/SA.2013.21006
Abstract:

随着通讯业务的竞争日趋激烈,客户关系管理的重要性日益突出,如何提高客户满意度、减少客户流失几率成为电信企业提高竞争力的重要策略。本文在总结国内外学者研究的基础上,采用广义线性混合模型分析客户流失原因,进行客户流失预测,为电信企业提供一定的参考。
With the increasingly fierce competition in the communication business and the growing importance of customer relationship management, how to improve the customer satisfaction and reduce the customer churn rate has became the main strategy to improve the competitiveness of telecom enterprises. Based on the summaries of former researches, this paper used the Generalized Linear Mixed Model to analyze the reasons of customer loss, find out the customer loss prediction model and provide several references for the telecom enterprises.





江西万载兴源冲铜矿流体包裹体地球化学研究
Geochemical Study of Fluid Inclusions from Xingyuanchong Copper Deposit in Wanzai, Jiangxi Province
 [PDF]

刘婷,,
Nuclear Science and Technology (NST) , 2014, DOI: 10.12677/NST.2014.22003
Abstract:
万载兴源冲铜矿地处宜丰景德镇板缘深断裂带西段黄茅地区。本文在前人研究基础上,通过对不同矿体矿石中的石英、方解石等脉石矿物进行系统的流体包裹体测温工作,来探讨矿区成矿流体来源。流体包裹体测温得出包裹体均一温度在75~440之间,主要分布于两个温度区间:110~190210~290,显示中低温的特征;盐度变化范围在1.74 wt%~22.58 wt%之间,显示中高盐度的特征。根据均一温度盐度图可以看出矿床成矿流体大致以海底喷流热液和与成岩作用有关的水为主,也有小部分岩浆热液的混合
Xingyuanchong copper deposit at Wanzai is located in the west section of Yifeng-Jingdezhen deep faults—Huangmao. On the basis of previous researches, and by carrying out temperature measurement of fluid inclusions systematically on gangue minerals, such as quartz and calcite, the authors discussed the sources of metallogenic fluids. The results show that 1) the homogenization temperatures of fluid inclusions vary in the range of 75?C~440?C, mainly in two sections: 110?C~ 190?C and 210?C~290?C, showing the feature of low medium temperatures; 2) the salinity ranges from 1.74 wt% to 22.58 wt%, suggesting medium high salinity. The homogenization temperature- salinity figure indicates the metallogeinic fluids are mainly submarine extrusive hydrothermal fluids and fluids related with diagenesis, and a small part of magmatic fluids.
B2C平台企业的供应商认证指标体系的实例研究
The Case Study of Supplier Certification Index System in B2C E-Commerce Platform
 [PDF]

黄逸, 丽菊
Service Science and Management (SSEM) , 2016, DOI: 10.12677/SSEM.2016.51002
Abstract:
以某电子商务平台企业为例,结合传统企业的供应商认证指标,在实地调研访谈的基础上,对不同合作模式的供应商进行分类,从前期准入和后期评估两个阶段建立B2C平台企业的供应商认证指标体系。最后运用层次分析法和模糊综合评价法相结合的方法建立评价模型,并通过问卷调查与调研获取指标数据进行实例分析,验证了认证指标和评价方法的有效性。
Taking an e-commerce platform as an example, combined with the traditional enterprise’s supplier certification index, the paper classifies different cooperation mode of suppliers, and then es-tablishes supplier certification index system of B2C platform enterprise from the early access and later evaluation two stages based on the field survey. Finally, we use analytic hierarchy process (AHP) and combine with fuzzy comprehensive evaluation method to establish evaluation model, and through the questionnaire survey to obtain data to carry on the example analysis, to verify the effectiveness of the authentication standards and evaluation methods.
建筑与建筑之间

工业建筑 , 2003, DOI: 10.13204/j.gyjz200306010
Abstract: 城市景观是由建筑及它们之间的空间共同构成的。城市的公共空间体现了建筑与建筑的关系。空间对建筑造型和组织具有积极的指导意义。注意公共活动空间的形成,可以使建筑与建筑协调起来;“琐碎”的建筑造型有助于积极空间的形成和宜人的空间尺度;只有把建筑作为城市空间序列的一部分进行设计,才能创造出有组织和多层次的城市景观
一种基于关键点的复制粘贴盲检测算法
Copy-Move Forgeries Detection Based on SIFT Algorithm
 [PDF]

, 杨正洪, 牛少彰
Computer Science and Application (CSA) , 2015, DOI: 10.12677/CSA.2015.57033
Abstract: 鉴于传统的复制粘贴篡改检测时间复杂度较高,而且对于图像的旋转缩放等后续润饰操作的鲁棒性不好,误报率高。提出了一种基于SIFT关键点的复制粘贴检测算法。首先利用SIFT算法对整幅图像提取SIFT关键点,再对提取到的关键点进行匹配。将匹配的关键点连接起来,来定位篡改区域。实验效果表明,相比较于传统的复制粘贴检测算法,该算法可以有效地检测出经过旋转缩放等几何变换的后续篡改。
In view of the higher time complexity of traditional copy-move forgery detection, bad robustness for the image rotation zoom and other follow-up retouching operations, a copy-move forgeries detection algorithm based on SIFT key points is studied. First, extract SIFT key points on the image by using SIFT algorithm, and then match the key point of extraction. Connect the key points of the match to locate the tampered area. Experimental results show that the algorithm can effectively detect the subsequent tampering of the geometric transformation such as rotation and zoom.
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