Inverse Combinatorial Optimization: A Survey on Problems, Methods, and Results

Given a (combinatorial) optimization problem and a feasible solution to it, the corresponding inverse optimization problem is to find a minimal adjustment of the cost function such that the given solution becomes optimum.Several such problems have been studied in the last twelve years. After formalizing the notion of an inverse problem and its variants, we present various methods for solving them. Then we discuss the problems considered in the literature and the results that have been obtained. Finally, we formulate some open problems.     

遗传算法优化神经网络及信用评价研究

研究关于公司神经网络信用评估问题的现状,提出遗传算法辅助网络训练策略(优化后的网络称为进化网络),克服传统网络建模中产生的局部极小缺陷。建立了适合于我国商业企业的信用评分指标体系;然后依据该指标体系建立了基于进化神经网络的信用评估模型;最后,利用样本公司实际指标数据对该模型的评分效果进行了比较研究。     

公众参与引导下的重大工程社会矛盾化解机制

新时代网络社会的不确定性、突变性等特征极大地颠覆了重大工程社会矛盾的阶段演化特性,对传统封闭性的社会矛盾化解机制设计提出了新挑战,具有多元非中心性的公众参与在应对该挑战中可发挥重要的引导作用。基于裂缝假说分析重大工程社会冲突困境,提出建立与公众参与水平相匹配的参与制度是困境化解的关键路径;将公众参与成熟度作为公众参与水平划分工具,按照低、中、高将其划分为3 个水平;引入网络化治理理论,建立与公众参与水平相匹配的公众参与机制,即形成“政府主导-社区参与”型、“政府引导-社会组织介入”型、“政府与社会组织协同合作”型机制,推动公众参与引导重大工程社会矛盾的自我疏导、自我治理和自我化解,形成全民共建共享的网络化治理新格局。     

加强大学生媒介素养教育的基本逻辑与现实路径

网络化已成为大学生的一种生存方式,但网络媒介的双重属性决定了它对社会生活的负面效应不可避免,引导大学生适应媒介化社会生活势在必行。新时期加强大学生媒介素养教育的逻辑起点在于：网络行为异化造成大学生社会角色迷失及其人格支离破碎;网络行为约束机制缺失冲击着大学生网络道德构建;网络媒介负外部性侵蚀着大学生身心健康。加强大学生媒介素养教育、构建立体化媒介素养教育模式,应着力于培育大学生的媒介伦理素养与主体意识,增强责任意识,理性使用网络媒介;大力强化教育管理者的网络媒介素养,提升实践育人能力,发挥协同效应;全力优化网络生态,降低网络环境对媒介素养教育的影响的风险。     

新型农业经营主体的经营绩效与差异分析——基于农村固定观察点的数据调查

新型农业经营主体的经营绩效关系到其可持续发展。采用农村固定观察点对我国各省区新型农业经营主体的调查数据,运用随机前沿分析法,对不同类型的经营主体的经营绩效进行分析,并进一步分析新型农业经营主体的差异性。结果表明：相比小农户而言,新型农业经营主体的经营绩效相对较高,但是其平均绩效还有很大的改善空间;新型农业经营主体面临融资难和人才缺乏的问题,且该问题在农民专业合作社中最为突出;我国家庭农场的经营绩效在三种新型农业经营主体中是最高的,其次是农业（龙头）企业,最后是农民专业合作社。对此,提出应完善土地“三权分置”机制,实现新型农业经营主体的规模化生产,进一步解决其融资难和人才缺乏的问题,加大政策扶持力度等建议。     

社会网络对民间金融风险的作用——基于社会网络结构的理论与实证分析

社会网络对民间金融风险的影响已被广泛认可,但是,究竟什么样的网络结构有抑制风险的作用,什么样的网络结构有扩增风险的作用？以资金互助会为例,将互助会涉及的社会网络按结构特征分为单个会的会内网络和多个会的会间网络,研究可知：（1）越紧密的会内网络结构以及越大的网络规模越有利于民间金融风险的控制。（2）跨会网络具有抑制和扩增风险两种作用,它是协同监督和惩罚机制生效的基础,因而对风险具有控制作用,但这种作用只在中介成员为会首时才显著;同时,它也构成了风险传播的通道,导致资金被分散到多个会中,因而提升了系统性风险。     

二元学习与创新绩效的作用机制——组织内部协作网络的调节作用

组织学习是驱动企业创新、实现技术追赶与超越追赶的关键因素,如何合理组织企业的利用式和探索式学习是企业构建研发体系的关键问题。学界对二元学习是否有利于企业的创新绩效存在截然不同的观点。同时,组织内部的情境因素是影响组织二元学习和创新绩效关系的最根本因素,组织内部研发协作网络是二元学习的重要载体。基于美国半导体行业企业十年间的专利数据,实证研究发现,不同维度的二元学习对企业创新绩效具有不同的影响,联合二元学习能够积极影响企业的创新绩效,平衡二元学习则会降低企业的创新绩效;内部研发协作网络密度在二元学习和创新绩效的关系中具有显著的调节作用,企业的内部协作网络密度越高,联合二元学习对企业创新绩效的积极影响越弱,平衡二元学习对创新绩效的负影响则加剧。     

R&D cooperation in collaborative consumption of research equipment: An ERGM approach

High-tech research infrastructure is essential for state-of-the-art research, but requires many resources. Relatively weak actors, such as SMEs, cannot secure enough of those. Applying the concept of collaborative consumption via digital platforms, we examine the cooperative behavior of Korean SMEs that share research equipment to overcome their lack of resources. Also, we analyze configurations of a collaborative consumption network using the Exponential Random Graph Model. Network structural factor analysis shows sufficient effects of network positive feedback through cooperative consumption with a variety of popular providers and attributes analysis shows that SMEs frequently engage in collaborative consumption with their counterparts in the same region. This new cooperative model can achieve a virtuous cycle of policies, as it increases the efficiency of research infrastructure, preventing the unnecessary building of new research equipment and enabling relocation of underutilized infrastructure and online reservation of equipment.     

Three‐Stage Decision‐Making Model under Restricted Conditions for Emergency Response to Ships Not under Control

A ship that is not under control (NUC) is a typical incident that poses serious problems when in confined waters close to shore. The emergency response to NUC ships is to select the best risk control options, which is a challenge in restricted conditions (e.g., time limitation, resource constraint, and information asymmetry), particularly in inland waterway transportation. To enable a quick and effective response, this article develops a three‐stage decision‐making framework for NUC ship handling. The core of this method is (1) to propose feasible options for each involved entity (e.g., maritime safety administration, NUC ship, and ships passing by) under resource constraint in the first stage, (2) to select the most feasible options by comparing the similarity of the new case and existing cases in the second stage, and (3) to make decisions considering the cooperation between the involved organizations by using a developed Bayesian network in the third stage. Consequently, this work provides a useful tool to achieve well‐organized management of NUC ships.     

Analysis of Regional Scale Risk of Whirling Disease in Populations of Colorado and Rio Grande Cutthroat Trout Using a Bayesian Belief Network Model

Introduction and spread of the parasite Myxobolus cerebralis, the causative agent of whirling disease, has contributed to the collapse of wild trout populations throughout the intermountain west. Of concern is the risk the disease may have on conservation and recovery of native cutthroat trout. We employed a Bayesian belief network to assess probability of whirling disease in Colorado River and Rio Grande cutthroat trout (Oncorhynchus clarkii pleuriticus and Oncorhynchus clarkii virginalis, respectively) within their current ranges in the southwest United States. Available habitat (as defined by gradient and elevation) for intermediate oligochaete worm host, Tubifex tubifex, exerted the greatest influence on the likelihood of infection, yet prevalence of stream barriers also affected the risk outcome. Management areas that had the highest likelihood of infected Colorado River cutthroat trout were in the eastern portion of their range, although the probability of infection was highest for populations in the southern, San Juan subbasin. Rio Grande cutthroat trout had a relatively low likelihood of infection, with populations in the southernmost Pecos management area predicted to be at greatest risk. The Bayesian risk assessment model predicted the likelihood of whirling disease infection from its principal transmission vector, fish movement, and suggested that barriers may be effective in reducing risk of exposure to native trout populations. Data gaps, especially with regard to location of spawning, highlighted the importance in developing monitoring plans that support future risk assessments and adaptive management for subspecies of cutthroat trout.