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1.
This study explores the value of special issues by analyzing the characteristics of special issues of Telecommunications Policy (TP). Specifically, this study examines the status of special issue publications, the characteristics of their articles compared with those of general issues, and the factors affecting article citations. For the analysis, all information on TP articles published from 1976 to 2018 was collected from the Scopus database. A comparative analysis as well as a negative binomial regression were conducted on papers published after 1994, when the first special issue was published. The results show that special issues are distinguished from general issues by various characteristics, such as multinational author collaboration, number of references, keywords, and funding. While general issue papers are more frequently cited in academia, special issue papers show better performance in terms of online captures and social media sharing. Moreover, the smaller number of variables affects the frequency of citations in the case of special issues, revealing that content and format are more influential than author factors.  相似文献   
2.
ABSTRACT

The aviation e-service system is an important part of support for business communication in regions covered by Belt and Road initiative. In exploring the role of airline companies in this system, we examine the structure of the network, which consists of airlines interconnections based on small data of individual attributes of aviation companies in aviation e-services, and study these interconnections across different groups using block modeling. The heuristic solution of airline companies in development of international communication and cooperation is further discussed. Among our policy implications for global managers, we suggest the enhancement of cross-regional cooperation among airlines.  相似文献   
3.
Traffic congestion is an unpreventable problem to avoid in a transportation network and it has negative effects on traffic accident, time wasting, traffic delay and safety problem. Besides, in transportation networks, drivers do not want to deal with traffic jam while traversing between specified origin-destination pair. Therefore, traffic assignment (TA) is imperative to improve traffic management, transportation safety, time, and cost savings. System Optimum Traffic Assignment Problem (SOTAP) is a kind of TA model which aims to minimize the total system travel time on the network, and satisfies the flow conservation constraints. To model the SOTAP more realistically, the imprecise parameters can be taken as fuzzy. Therefore, in this paper, we focus on converting the conventional SOTAP to a fuzzy quadratic programming problem (QPP) which is named System Optimum Fuzzy Traffic Assignment Problem (SOFTAP). Here, link travel time is expressed with BPR function as generally used in the literature by converting to fuzzy except link-dependent parameters. Thus, the nonlinear objective function of SOFTAP is expressed in terms of fuzzy link flows and fuzzy link travel times. A solution approach from the literature is modified to the reconstructed SOFTAP.  相似文献   
4.
知识互动程度评价对改善高校跨学科创新团队知识互动具有重要意义。在界定高校跨学科创新团队知识互动及知识互动程度内涵的基础上,创新性地从知识互动深度、互动广度、互动时间3个维度建立知识互动程度评价指标体系。进一步地,采用三角模糊权重、熵权和模糊积分相结合的方法,构建知识互动程度评价模型。最后,选取一所高校跨学科创新团队进行实例分析,验证评价模型的可操作性,可为高校跨学科创新团队知识互动程度评价提供一个新视角。  相似文献   
5.
Sustainable Public Procurement is an integral part of sustainable development because of ever increasing government expenditures. Most of the developing countries lack the required infrastructure which may support public sector sustainability. The aim of this study is to assess the critical factors which resist the implementation of sustainable procurement in public sector of Pakistan. We used Interpretive Structural Model to investigate and rank the interrelationships among different factors of sustainable procurement. With the help of literature and Likert scale instrument, we found twelve key barriers that resist sustainable procurement implementation. We also examined tender documents of 75 different public sector universities of Pakistan but found absence of sustainability element in the documents. External factors namely government legislation and stakeholders' pressure are found most critical barriers as compared to inter organizational factors. The study is also important to highlight the hurdles in the way of sustainable development. First, the government must introduce rules and regulations to implement the sustainable procurement. Stakeholders and donors must put pressure on organizations for adopting sustainable procurement. Sustainability education should be made mandatory part of curriculum and employees should be given regular training on sustainability. Further, public procurement policies at government and institutional levels are required to be revisited towards a circular economy.  相似文献   
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7.
This research explores the physical infrastructure and flight consolidation efficiency drivers of Eurasian airports regarding their infrastructure and movement productivity levels. A novel Fuzzy Double-Frontier Network DEA (FDFNDEA) model is proposed to investigate the relationship between desirable (freight and passenger turnovers) and undesirable (pollutant emission levels due to aircraft movements) outputs against the respective infrastructure usage, fuel consumed, and movements performed at each of the 23 Eurasian airports from 2000 to 2018. This balance between desirable and undesirable outputs emerges spatially and temporally due to the evolution of the airport system's productive resources at each one of the Eurasian countries over the period observed. Shannon's entropy is used as the cornerstone to quantify the input and output vagueness of this evolution in Triangular Fuzzy Numbers (TFN), thus allowing the accurate building of alternative optimistic and pessimistic double-frontier efficiency. Differently from previous research, Shannon's entropy is the key for measuring input and output vagueness levels in light of the maximal entropy principle. This principle states that the distribution that best represents the current state of knowledge is the one with largest entropy. Maximal entropy yields bias-free decision-making in the sense that the input/output distributional profiles for Eurasian airports contain the maximal possible heterogeneity, working as a robust or best/worst-case scenario against eventual unconsidered assumptions. Hence, optimistic and pessimistic Malmquist Productivity Indexes (MPI) for overall and each stage productivity results are subsequently regressed against contextual variables related to airport characteristics and regional socio-demographic and economic indicators of each Eurasian country using bootstrapped Cauchy regressions. The findings revealed the spatial heterogeneity of productivity factors and airport performance across Eurasia. Results also demonstrated the negative impact of income inequality and the positive impact of private participation on technological progression in the Eurasian airport industry.  相似文献   
8.
基于“互联网+”大背景,跨界创新成为实现突破性技术创新的重要形式。通过现有文献分析,构建了跨界创新在突破性技术创新模糊前端的作用模型,并运用案例研究法,以无人驾驶汽车为例对模型进行释义。研究表明,跨界创新在突破性技术创新模糊前端起到重要作用,跨界创新可分为跨界搜索与跨界合作,跨界搜索有助于创意搜集和创意筛选,识别突破性技术创新机会;跨界合作有助于提升研发效率和成功率;跨界搜索与跨界合作相辅相成,共同致力于突破性技术研发成功。  相似文献   
9.
This paper, following McGoun's (1997) seminal article comparing the economy of financial securities to a hyperreal poker game, argues that finance and accounting researchers should take the “linguistic turn” that has rejuvenated theory and research in many, if not most, of the social science and humanities in recent decades. In general terms, this means following Ludwig Wittgenstein's language game paradigm rather than Karl Popper's scientific deductive hypothesis testing methodology. The paper illustrates this by drawing on some of Jean Baudrillard's' ideas, particularly his concept of hyperreality and his phases of the image theoretic.The paper presents a poststructuralist genealogical analysis of the radical ruptures and reformulation of the meaning attributed to the accounting sign of earnings over the feudal, counterfeit, production, and simulation eras. It concludes that, as with many other signs in contemporary society, the earnings sign no longer has any relationship with, nor does it any longer refer to, any real or intrinsic profit but instead floats ungrounded in today's financial economy.The paper recommends that researchers in finance and accounting adopt paradigms from literary theory, semiotics, linguistics, and semiology rather than continue to rely on economics-based theory, which has lost its power for explaining and predicting happenings in today's financial economy of self-referencing models and images.  相似文献   
10.
Product life cycle (PLC) prediction plays a crucial role in strategic planning and policy definition for high-technology products. Forecast methodologies which can predict PLCs accurately can help to achieve successful strategic decision-making, forecasting, and foresight activities in high-technology firms, research institutes, governments, and universities. Over the past few decades, even though analytic framework strategies have been proposed for production, marketing, R&D (research and development), and finance, aiming at each stage of PLCs, forecast methodologies with which to predict PLCs are few. The purpose of this research is to develop a novel forecast methodology to allow for predictions of product life time (PLT) and the annual shipment of products during the entire PLC of multiple generation products. A novel two-stage fuzzy piecewise regression analysis method is proposed in this paper. In the first stage, the product life-time of the specific generation to be analyzed will be predicted by the fuzzy piecewise regression line that is derived based upon the product life-time of earlier generations. In the second stage of the forecast methodology, the annual shipment of products of the specified generation will be predicted by deriving annual fuzzy regression lines for each generation, based upon the historical data on the earlier generations' products. An empirical study predicting the life-time and the annual shipment of the 16 Mb (Mega bit) DRAM (Dynamic Random Access Memory) PLC is illustrated to validate the analytical process. The results demonstrate that two-stage fuzzy piecewise regression analysis can predict multiple generation PLT and PLC precisely, thereby serving as a foundation for future strategic planning, policy definitions and foresights.  相似文献   
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