Synthesis of strategies in post-COVID-19 public sector supply chains under an intuitionistic fuzzy environment

Entities in public sector supply chains (SCs) often operate independently despite having interdependent objectives. Such a fragmented operational design poses several problems magnified by the presence of necessary public health measures fueled by COVID-19. This work contributes to the domain literature by introducing an overarching framework for synthesizing strategies in public sector SCs. The underlying component is the translation of information from the upstream to the downstream entities of the SCs, which is carried out by a Kano-enhanced quality function deployment. The proposed framework introduces intuitionistic fuzzy (IF) decision maps with the aid of the full consistency method to incorporate inherent interrelationships among strategies in the translation agenda. Under an IF environment that better captures judgment uncertainties, an actual case study of a multi-level public sector SC motivated by a government-funded project under the COVID-19 pandemic is demonstrated in this work. Findings of the case suggest that the government prioritizes meeting all project objectives. This requirement is reflected in the downstream SC. The project planning entity focuses on creating an overarching plan of operations, material request entity on complying with government procurement protocols, and maintaining public health and safety in operations for the procurement entity. Results show the effective synthesis of strategies across the SC, ensuring SC integration and collaboration. The case study demonstrates that maintaining public health and safety is a significant component of post-COVID-19 public sector SCs. Several practical insights on the synthesis of public sector SC strategies are also provided in this work.     

吸声材料在变频发电机组噪声控制中的应用

吸声是一种有效的降噪措施，吸声材料广泛用于各种机械设备及其部件的噪声控制中。通过对某1.7 kW变频发电机组的噪声进行测试，发现该发电机组存在原状态吸声材料降噪效果不佳的问题，25%～75%负载噪声仅仅降低了0.1～0.4 dB(A) ，在空载工况下，发电机组的噪声反而增大了1.1 dB(A)。通过更换4种不同参数的吸声材料进行对比测试，结果发现材质为聚氨酯、密度为35 kg/m3、厚度为10 mm的吸声材料降噪效果最好。与原状态相比，4种负载（空载、25%负载、50%负载和75%负载）下的噪声分别降低了1.1 、0.8、0.2 、0.6 dB(A)，发电机组的噪声得到了进一步改善。吸声材料的降噪分析结果为发电机组的噪声控制提供思路。     

Forecasting expected shortfall: Should we use a multivariate model for stock market factors?

Is univariate or multivariate modeling more effective when forecasting the market risk of stock portfolios? We examine this question in the context of forecasting the one-week-ahead expected shortfall of a stock portfolio based on its exposure to the Fama–French and momentum factors. Applying extensive tests and comparisons, we find that in most cases there are no statistically significant differences between the forecasting accuracy of the two approaches. This result suggests that univariate models, which are more parsimonious and simpler to implement than multivariate factor-based models, can be used to forecast the downside risk of equity portfolios without losses in precision.     

基于fsQCA方法的煤矿突发事件影响因素组态路径研究

为探究煤矿突发事件的发生机制，以40起煤矿突发事件为案例对象，结合事故致因“2-4”模型（24Model），应用模糊集定性比较分析（fsQCA）方法，识别煤矿突发事件的组态路径。结果表明，单个条件对煤矿突发事件的解释力较弱，但不安全物态、安全管理体系缺欠、安全文化缺欠和组织外部原因发挥显著影响。通过组态分析得到煤矿突发事件的3条路径，为煤矿事故致因领域的研究提供有益借鉴。     

基于概率分布的犹豫模糊集多属性群决策法及应用

因决策者本身对每个术语有不同的偏好，其做决策时可能会犹豫，决策结果会因人而异。针对智能物流实验室设备供应商选择过程进行决策分析,首先收集专家的犹豫模糊语言术语评价信息；其次综合评价专家的共识度和犹豫度确定其权重；再改进排序位置法，优化决策方法，提出一种鲁棒性很强的基于概率分布的犹豫模糊MULTIMOORA群决策方法。最后，通过对比分析验证该方法的有效性。     

Rational stability of choice functions

Two independent approaches have been used to analyze choices. A prominent notion is rationalizability: individuals choose maximizing binary relations. An alternative is to analyze choices in terms of standards of behavior with the notion of von Neumann–Morgenstern (vNM)-stability. We introduce a new concept ($r-$stability) that in turn extends the notion of stability and rationality. Our main result establishes that every rationalizable choice function is $r-$stable and every vNM-stable choice has an $r-$stable selection. An appealing property of $r-$stability is that well-known solution concepts (top cycle, uncovered set, …) are $r-$stable, while they are neither rationalizable nor vNM-stable.     

柴油发电机组国内主要企业的专利现状分析

柴油发电机组在国内外的需求不断增加,进出口对产品技术的重视和要求也越来越高,而国内柴油发电机组生产企业依然侧重组装,缺乏对技术的投入及研发的系统管理。通过对国内主要柴油发电机组生产企业上海康诚、上海鼎新、上海科泰、无锡瑞昌、无锡百发、江西泰豪、深圳赛瓦特7家企业的专利现状分析,洞察生产企业的技术优势与研发策略,从而为其它柴油发电机组国内企业提供发展思路借鉴。     

产业技术创新战略联盟利益分配机制研究综述

从联盟利益分配客体、利益分配主体,以及利益分配机制的具体建构等方面对国内相关研究进行综述表明,由于缺乏深入的个案研究,以及采集经验数据存在较大难度,致使现有研究大多偏向于宏观化和模型化,可操作性和合理性还有待验证,实际应用效果还有待于进一步的考核评估。联盟利益分配客体的确立,特别是对间接利益的定量化,以及根据利益主体的个体差异性、利益客体的阶段性,选择合理的分配方式等方面研究还有待加强。     

复杂信任网络群组综合评价方法及应用研究

考虑评价环境的复杂不确定性、评价专家的信任行为特征以及群组专家的共识等问题，提出了一种区间Fermatean模糊信任网络群组综合评价方法。首先，针对区间Fermatean模糊评价信息的集成问题，提出了区间Fermatean模糊信息的运算规则，并在此基础上提出了一种区间Fermatean模糊Frank集成方法。其次，考虑到评价专家间信任关系对专家权重和共识达成的影响，构建了基于语言术语的信任网络以计算专家权重，同时设计了个性化反馈机制，进而构建了信任共识交互模型以提高群组共识度。此外，针对评价指标权重未知的情形,提出了区间Fermatean模糊熵权法获取指标权重。最后，通过高校商科类本科生统计设计能力的评价问题验证所提出方法的可行性和优越性。