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901.
In general cases, to find the exact upper bound on the minimal total cost of the transportation problem with varying demands and supplies is an NP-hard problem. In literature, there are only two approaches with several shortcomings to solve the problem. In this paper, the problem is formulated as a bi-level programming model, and proven to be solvable in a polynomial time if the sum of the lower bounds for all the supplies is no less than the sum of the upper bounds for all the demands; and a heuristic algorithm named TPVDS-A based on genetic algorithm is developed as an efficient and robust solution method of the model. Computational experiments on benchmark and new randomly generated instances show that the TPVDS-A algorithm outperforms the two existing approaches.  相似文献   
902.
《决策科学》2017,48(1):39-70
Manufacturing process improvement teams often draw upon cross‐functional expertise. However, teams dominated by a single or few functions often do not achieve the desired interdisciplinary learning and cooperation, which in turn could negatively affect the performance of that cross‐functional team. Through an empirical analysis of 149 manufacturing process improvement teams in six SIC industrial categories, we show that even after controlling for several factors such as team size, number of functions, gender diversity, ethnicity, number of management levels, and geographic dispersion of team members, psychological safety of work environment fully mediates the relationship between functional dominance and team performance. We also confirm that a team leader possessing high interpersonal justice mitigates the deficiency of dominated teams and improves team performance by fostering a psychologically safe work environment. Our recommendation therefore is that when a dominated team is unavoidable due to the needed skill sets or other organizational considerations, to ensure success it is imperative that the firm chooses a team leader who can promote psychological safety by being just, and who can effectively encourage input from all functional team members and give them objective feedback.  相似文献   
903.
分析了股权众筹融资方和投资方的最优策略.依据股权众筹的流程,构建了股权众筹过程中投融资方利益博弈的3阶段模型,并在同时满足融资方与投资方预期收益最大化的条件下,求解了相应的最优化问题并给出了投融资方最优策略的解析式.研究结果表明,在参数满足一定条件时,股权众筹投融资方均存在最优策略,且最优策略受边际收益、项目成功概率、预期回报率等因素的影响.  相似文献   
904.
提出智能创新生产力概念及其理论模型,发现智能演进创新和非守恒规律及其作用原理,研究智能创新的核心生产力,即智能创新克服人的生理认知能力有限性与客观物质(能量)变化无限性之间的悖论,创造利用物质世界的无穷手段和能力,创造时间和空间,解决资源稀缺与社会需求矛盾;在此基础上发现智能创新自认知、自选择和自组织原理,破解著名的智能认知体系结构与优化代理体系结构(这是本文重要发现之一),研究智能创新的系统生产力,即智能经济相对于传统经济可以达到和实现理想的生产过程,使生产活动在开放的资源空间和动态系统中进行,虚拟智能的物理化使经济活动没有时空约束和资源稀缺约束,创新经济和社会的生产方式与组织形态.本文所提出的智能创新生产力理论模型,即智能创新的核心生产与系统生产力概念也为中国经济改革发展提出重要思考.  相似文献   
905.
Since the Last Planner System® (LPS) was devised in the early 90s, a number of studies have pointed out the need to understand the underlying theory in which it is based on. The Language-Action Perspective (LAP) has been suggested as a suitable approach to understand the management of commitments in the LPS. This paper aims to assess the contribution of LAP to understand construction planning and control systems based on LPS. Two case studies were carried out in different construction companies, both highly experienced on the use of LPS. The results reveal the role of LAP for creating explicit representations of commitment flows that can be used to explain the sources of complexity and failures in planning systems, as well as for describing the profile of planning and control meetings.  相似文献   
906.
Smart manufacturing systems (SMSs) are envisioned to contain highly automated and IT-driven production systems. To address the complexity that arises in such systems, a standard and holistic model for describing its activities and their interrelationships is needed. This paper introduces a factory design and improvement (FDI) activity model and illustrates a case study of FDI in an electromechanical component factory. In essence, FDI is a reference activity model that encompasses a range of manufacturing system activities for designing and improving a factory during its initial development and also its operational phases. The FDI model shows not only the dependency between activities and manufacturing control levels but also the pieces of information and software functions each activity relies on. We envision that the availability of these pieces of information in digital form to integrate across the software functions will increase the agility of factory design and improvement projects. Therefore, our future work lies in contributing to standards for exchanging such information.  相似文献   
907.
This article uses a game‐theoretic approach to analyze the risk of cross‐milieu terrorist collaboration—the possibility that, despite marked ideological differences, extremist groups from very different milieus might align to a degree where operational collaboration against Western societies becomes possible. Based upon theoretical insights drawn from a variety of literatures, a bargaining model is constructed that reflects the various benefits and costs for terrorists’ collaboration across ideological milieus. Analyzed in both sequential and simultaneous decision‐making contexts and through numerical simulations, the model confirms several theoretical arguments. The most important of these is that although likely to be quite rare, successful collaboration across terrorist milieus is indeed feasible in certain circumstances. The model also highlights several structural elements that might play a larger role than previously recognized in the collaboration decision, including that the prospect of nonmaterial gains (amplification of terror and reputational boost) plays at least as important a role in the decision to collaborate as potential increased capabilities does. Numerical simulation further suggests that prospects for successful collaboration over most scenarios (including operational) increase when a large, effective Islamist terrorist organization initiates collaboration with a smaller right‐wing group, as compared with the other scenarios considered. Although the small number of historical cases precludes robust statistical validation, the simulation results are supported by existing empirical evidence of collaboration between Islamists and right‐ or left‐wing extremists. The game‐theoretic approach, therefore, provides guidance regarding the circumstances under which such an unholy alliance of violent actors is likely to succeed.  相似文献   
908.
Acrylamide forms primarily from a reaction between reducing sugars (e.g., glucose and fructose) and an amino acid (asparagine, Asn) formed naturally in foods, including potatoes. This reaction occurs when carbohydrate‐rich foods are heated at temperatures above 120 °C. Multiple potato varieties were transformed with potato genomic DNA that results in down‐regulation of the expression of the asparagine synthetase‐1 gene (Asn1), significantly reducing synthesis of free Asn, and consequently lowering the potential to form acrylamide during cooking. These potatoes with low acrylamide potential (LAP) were tested in agronomic trials, and processed into French fries and potato chips. Decreased levels of acrylamide were measured in these cooked food products when derived from LAP potatoes compared with those derived from conventional potatoes. These reductions can be directly attributed to reduction in Asn levels in the LAP potatoes. The corresponding average reduction in exposure to acrylamide from French fry and potato chip consumption is estimated to be 65%, which would amount to approximately a 25% reduction in overall dietary exposure. Considering that children consume nearly three times more acrylamide than adults on a per kg body weight basis, they would experience the most impact from the reduced acrylamide associated with LAP potatoes. The potential public health impacts, in context of dietary acrylamide exposure reduction, are discussed in this study.  相似文献   
909.
U.S. airports and airliners are prime terrorist targets. Not only do the facilities and equipment represent high‐value assets, but the fear and dread that is spread by such attacks can have tremendous effects on the U.S. economy. This article presents the methodology, data, and estimates of the macroeconomic impacts stemming from behavioral responses to a simulated terrorist attack on a U.S. airport and on a domestic airliner. The analysis is based on risk‐perception surveys of these two scenarios. The responses relate to reduced demand for airline travel, shifts to other modes, spending on nontravel items, and savings of potential travel expenditures by U.S. resident passengers considering flying domestic routes. We translate these responses to individual spending categories and feed these direct impact results into a computable general equilibrium (CGE) model of the U.S. economy to ascertain the indirect and total impacts on both the airline industry and the economy as a whole. Overall, the estimated impacts on GDP of both types of attacks exceed $10B. We find that the behavioral economic impacts are almost an order of magnitude higher than the ordinary business interruption impacts for the airliner attack and nearly two orders of magnitude higher for the airport attack. The results are robust to sensitivity tests on the travel behavior of U.S. residents in response to terrorism.  相似文献   
910.
Despite considerable research investigating the role of influence tactics on work-related outcomes in organizations, consensus on the effectiveness of influence tactics has been elusive. Specifically, there is a lack of integration concerning the relationships between proactive influence tactics and their outcomes. We investigate the effectiveness of 11 influence tactics from a comprehensive perspective using meta-analytic techniques. In particular, the current study focuses on relationships between each of the 11 influence tactics (i.e., rational persuasion, exchange, inspirational appeal, legitimating, apprising, pressure, collaboration, ingratiation, consultation, personal appeals, and coalition) and task- and relations-oriented outcomes. In addition, we investigate the moderating effects of the direction of influence tactics, measurement of influence tactics, singular influence tactic (versus use of a combination of influence tactics), independence of data sources, and study setting involved in the study. Regardless of task- and relations-oriented outcomes, based on 49 independent samples (N = 8987), our results show positive relationships between outcomes and rational persuasion, inspirational appeal, apprising, collaboration, ingratiation, consultation, and a negative relationship between pressure and outcomes. Rational persuasion is the only tactic which held stable positive relationships with both categories of outcomes regardless of moderating factors. Implications and directions for future research in the area of influence tactics are discussed.  相似文献   
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