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1.
共同购买网络的推荐系统应用越加广泛,仅基于网络内生结构变量研究其共同购买链接的经济意义已有局限,故加入网络口碑这一外生变量,进行更全面的分析。采用了社会网络方法中指数随机图模型进行建模,主要围绕产品销售量、产品入度、差评率和评论数4个方面因素,探究其对共同购买网络中共同购买链接形成的影响。结果显示,销售量、产品入度和评论数对共同购买链接形成的影响呈正比关系,而差评率则会显著地降低产品共同购买的几率。该指数随机图构建出的共同购买网络为在线电商平台管理网络口碑和推荐系统优化设计提供有益参考。  相似文献   
2.
The importance, benefits, and impact of integration of decisions within supply chains have long been investigated by many researchers. Order acceptance and supplier selection are two of the most critical decisions for supply chain managers. Throughout the process of order acceptance, a manufacturer has to decide which orders to be accepted and processed and based on the accepted orders, the volume of required raw material is determined. On the other hand, a manufacturer aims to choose one or several suppliers among all possible choices to provide sufficient raw material for the accepted orders, subject to different criteria such as list price, transportation cost, etc. This paper addresses an integrated framework for profit maximization in an integrated supplier selection, order acceptance and scheduling problem in a single-machine environment with multiple customers. There is substantial literature on the problems of supplier selection and order acceptance; however, to the best of our knowledge, this paper is the first research that integrates these essential decisions in the form of a mathematical model to maximize the total profit. The problem is NP-hard in nature; therefore, solving to optimality is not practically possible for problems with medium and large size. For that purpose, we developed a Heuristic Algorithm (HA) to solve the problem above in a reasonable time, with proper accuracy. Results from this heuristic algorithm are compared with that of a commercial solver (GAMS) and the well-known Genetic Algorithm (GA) and Variable Neighborhood Search (VNS). Computational experiments demonstrate that the developed heuristic algorithm is more efficient in comparison with other tested methods.  相似文献   
3.
Scratch and mar can critically impact the aesthetics of polymeric surfaces. Their quantification poses considerable challenges, especially for subtle mar damages. Here, we report a new standardized approach that utilizes a modified ASTM/ISO scratch test standard and a psychophysical tool to quantify scratch and mar visibility. The new methodology was then used to study the influence of color, gloss, and texture perception on scratch and mar visibility resistance. These factors have limited influence on scratch visibility onset. However, faint mar damage is more sensitive to surface perceptual properties. It has been found that overall visibility throughout the entire damage path is a better indicator for ranking mar damage. Results show that contrast slope variation parameter can consistently quantify mar visibility and simulate human perception. Green, glossy, and smooth surfaces tend to have less mar visibility resistance. The effect of a fatty amide slip agent was also investigated. These modifiers improved both scratch and mar visibility resistance. This unique approach paves the way for a straightforward universal standard that can be utilized to reliably quantify scratch and mar visibility in polymers, thereby opening up a new avenue for the design of polymeric materials with better scratch and mar visibility resistance.  相似文献   
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硅烷偶联剂KH550,KH560和KH570被用于对二乙基次膦酸铝粉体阻燃剂的表面改性。经该法改性的二乙基次膦酸铝粉体的吸水率被明显降低,在PBT中的相容性被提高,并且在PBT中的分散度也得到提高。该改性方法有效地解决了利用化学沉淀法制备该阻燃剂时粉体易团聚的问题。  相似文献   
6.
通过DPD方法(耗散粒子动力学)对PVC木塑(主要成分PVC与木纤维:质量比为100∶24)与水性氟碳漆(主要成分聚三氟氯乙烯)的相容情况进行计算机模拟计算,研究发现PVC以及木纤维与聚三氟氯乙烯相容性都极差,系统严重分相,通过加入水性丙烯酸底漆来解决水性氟碳漆与PVC/木粉体系的相容性问题,漆膜附着力测试与计算结果完全吻合,试验证实DPD方法可以很好地预测各类漆与高分子材料的相容性,在工业上指导材料涂漆类型的选择。  相似文献   
7.
For the scratch process of polypropylene (PP), the stick-slip phenomenon always exists and contributes to the observed periodic surface damage patterns. The stick-slip, one main cause for scratch visibility, alters the surface characteristics of substrate and eventually induces scratch visibility. Both ASTM/ISO and Erichsen scratch test methods are employed to study the stick-slip phenomenon and its effects on scratch behavior of PP. Image analysis shows that the stick-slip phenomenon was responsible for material removal and severe surface damage. Possible solutions to improve the scratch performance of polymeric materials are also discussed in this paper.  相似文献   
8.
针对传统大数据特征加密方法中大数据精度较差、加密耗时较长的问题,提出基于信息熵抑制的大数据特征隐匿性加密方法。分析信息熵抑制相关理论,采用信息熵映射函数对大数据分类,将信息熵抑制过程转化为计算2个文件相似性的过程,并根据余弦相似度公式以及Hamming距离值计算数据相似度,完成数据消冗。在完成数据消冗的基础上,分析分组密码方法和ECC加密方法,结合两种方法得到大数据特征隐匿性加密处理计算公式,实现基于信息熵抑制的大数据特征隐匿性加密。实验研究结果表明,所提方法能够有效去除冗余数据,提升大数据精度,加快数据加密的处理速度,高效完成大数据加密过程。  相似文献   
9.
随着我国社会主义现代化建设的发展,信息化、办公管理现代化的要求愈来愈迫切,作为现代化管理的重要手段—计算机应用已深入各领域、各行业、各部门。计算机知识的掌握和应用是高职高专学生服务社会的必备条件。由于信息技术的快速发展及高职高专的特点,本文针对我院多年来实践"以证代考"模式的实施方案、取得效果、存在问题几个方面进行阐述。  相似文献   
10.
通过宏观分析、红外光谱分析、热分析和高压毛细管流变分析对ASA树脂制件分层原因进行了分析。结果表明:发生分层的ASA树脂制件混入了PP树脂,两者流动性和结晶性的差异导致了制件的分层。  相似文献   
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