预测信息传播中的转发选择

在信息传播中,用户在重复接收同一信息的情况下其转发行为会具有一定的倾向性。对这种转发的倾向性建模是影响力分析、传播动力学、社会推荐等一系列信息传播相关应用研究领域中的一个关键问题。本文假设用户的转发选择行为主要由用户间的人际影响力决定。人际影响力的大小由信息传播者的影响力和信息接收者的易感性共同作用。本文从真实的信息传播记录中推断出用户隐式的影响力和易感性,进而提出了一种转发选择模型。该模型能够有效解决目前方法存在的对转发选择行为建模不充分和模型泛化能力差的问题。本文选取典型的转发选择建模方法作为比较,将所提的转发选择模型在新浪微博数据上进行对比验证。实验表明,本文所提的模型在两种评价指标上均取得更好效果,证明了所提模型的有效性。     

A consensus model for hesitant fuzzy preference relations and its application in water allocation management

This paper investigates a consensus model for hesitant fuzzy preference relations (HFPRs). First, we present a revised definition of HFPRs, in which the values are not ordered for the hesitant fuzzy element. Second, we propose an additive consistency based estimation measure to normalize the HFPRs, based on which, a consensus model is developed. Here, two feedback mechanisms are proposed, namely, interactive mechanism and automatic mechanism, to obtain a solution with desired consistency and consensus levels. In the interactive mechanism, the experts are suggested to give their new preference values in a specific range. If the experts are unwilling to offer their updated preferences, the automatic mechanism could be adopted to carry out the consensus process. Induced ordered weighted averaging (IOWA) operator is used to aggregate the individual HFPRs into a collective one. A score HFPR is proposed for collective HFPR, and then the quantifier-guided dominance degrees of alternatives by using an OWA operator are obtained to rank the alternatives. Finally, both a case of study for water allocation management in Jiangxi Province of China and a comparison with the existing approaches are carried out to show the advantages of the proposed method.     

A novel fuzzy multi-criteria decision framework for sustainable supplier selection with incomplete information

Both academic and corporate interest in sustainable supply chains has increased in recent years. Supplier selection process is one of the key operational tasks for sustainable supply chain management. This paper examines the problem of identifying an effective model based on sustainability principles for supplier selection operations in supply chains. Due to its multi-criteria nature, the sustainable supplier evaluation process requires an appropriate multi-criteria analysis and solution approach. The approach should also consider that decision makers might face situations such as time pressure, lack of expertise in related issue, etc., during the evaluation process. The paper develops a novel approach based on fuzzy analytic network process within multi-person decision-making schema under incomplete preference relations. The method not only makes sufficient evaluations using the provided preference information, but also maintains the consistency level of the evaluations. Finally, the paper analyzes the sustainability of a number of suppliers in a real-life problem to demonstrate the validity of the proposed evaluation model.     

移动机器人闭环检测的视觉字典树金字塔TF-IDF得分匹配方法

针对移动机器人视觉闭环检测中,基于视觉字典本的场景外观表征性能受制于有限单词个数以及算法效率低的不足,本文对机器人视觉特征分层量化,构建视觉字典树, 计算树节点的TF-IDF熵作为对应视觉单词的权重,生成图像--单词逆向文档索引.为消除视觉字典本的单尺度量化误差,并克服基于字典树投影路径的平面匹配模式中不 区分不同层次节点的区分度对闭环检测的影响,本文融合字典树低层单词的强表征性和高层单词的强鲁棒性,提出由下而上逐层计算图像间相似性增量的金字塔得分匹 配方法.将不同时刻相似性大于阈值的图像位置提取为候选闭环,通过后验确认操作剔除误正闭环.在移动机器人视觉闭环检测实验中,本文算法提高了图像相似性计算 的效率和准确性,提高了闭环检测的准确率和召回率.     

Identification of chemical oviposition stimulants from rice grain forSitophilus zeamais motschulsky (Coleoptera,Curculionidae)

Chemical components stimulating oviposition bySitophilus zeamais in rice grain were isolated from rice bran and were found to be a mixture of ferulates, diglycerides, and free sterols. Oviposition preference of the species can be induced by synergistic action of these compounds.     

基于PCA-LINMAP-FCE的通信系统维修性评价方法

为提高通信系统维修性评价的实用性和可操作性,提出了一种基于 PCA-LINMAP-FCE 的维修性评价方法。在构建简化的维修性评价指标体系的基础上,将 PCA-LINMAP 与模糊综合评判（ FCE）方法相结合,从定量和定性的角度对维修性进行评价。实例仿真分析表明,该方法可操作性强,且有效地降低了评价的主观随意性,使维修设计和作业人员全面掌控通信系统装备维修性的影响因素,能够为科学制定设计方案和维修实施决策方案提供决策信息。     

A study of replacement rules for a parallel fleet replacement problem based on user preference utilization pattern and alternative fuel considerations

Parallel fleet replacement problems deal with determining an optimal replacement schedule that results in a minimal total cost of owning and operating a fleet within a finite planning horizon. In this paper, the fleet consists of service vehicles, varying in age and cumulative mileage, commonly owned by government agencies or private business organizations. The paper focuses on three main aspects of the problem, including the effects of some widely used replacement rules, consideration of alternative fuel vehicles for replacement, and a new “user preference” utilization pattern. The vehicle replacement rules under study include purchase-new-vehicles-only, no-splitting-in-selling, one-purchase-choice, older-vehicles-selling, and all-or-none rules. The initial fleet consists of gasoline vehicles, while alternative-fuel vehicles using either compressed natural gas (CNG) or liquefied petroleum gas (LPG) are included as challengers in every replacement decision period. The user preference utilization pattern denotes a pattern in which yearly usage of vehicles declines as the vehicles grow older or have higher cumulative mileage. Integer programming formulation of the defined problem that incorporates these new factors is provided. Small numerical examples under various scenarios and a large problem instance with model parameters estimated from actual data are solved to optimality to gain some insights about the replacement rules and other considered factors.     

A consistency and consensus based decision support model for group decision making with multiplicative preference relations

In group decision making (GDM) with multiplicative preference relations (also known as pairwise comparison matrices in the Analytical Hierarchy Process), to come to a meaningful and reliable solution, it is preferable to consider individual consistency and group consensus in the decision process. This paper provides a decision support model to aid the group consensus process while keeping an acceptable individual consistency for each decision maker. The concept of an individual consistency index and a group consensus index is introduced based on the Hadamard product of two matrices. Two algorithms are presented in the designed support model. The first algorithm is utilized to convert an unacceptable preference relation to an acceptable one. The second algorithm is designed to assist the group in achieving a predefined consensus level. The main characteristics of our model are that: (1) it is independent of the prioritization method used in the consensus process; (2) it ensures that each individual multiplicative preference relation is of acceptable consistency when the predefined consensus level is achieved. Finally, some numerical examples are given to verify the effectiveness of our model.     

基于用户关系挖掘的多策略推荐算法

个性化推荐服务为解决网络信息过载问题提供了有效手段。传统的推荐方法大多只关注于如何提高推荐的准确性,而忽略了推荐多样性对用户体验的影响。文章将社会网络用户关系挖掘应用于用户偏好预测及推荐中,提出了一种基于用户关系挖掘的多策略推荐算法。采用信任传播模型挖掘用户间的信任度,计算用户偏好配置文件的余弦相似性获得用户间的相似度,并给出4种将用户信任度、相似度结合的策略,在定义用户偏好预测函数的基础上采用Topn原则为用户给出推荐结果。实验结果表明,文章方法不仅减少了数据稀疏性的影响,而且兼顾了推荐准确性与多样性指标,提高了推荐系统的整体性能。     

我国非营利组织税收优惠法律制度完善的研究

我国为鼓励非营利组织的发展,为捐赠人和非营利组织自身都制定了一系列税收优惠措施。但是现阶段的税收优惠制度存在的诸多不足不能满足我国非营利组织的发展要求。我国应从合理区分非营利组织性质,对非营利组织的营利收入予以合理免税、改进捐赠激励机制等方面完善非营利组织的税收优惠法律制度,以便实现非营利组织的可持续发展。