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201.
Over the past decade, social media have become an increasingly important component in the ways broadcasters communicate with their audiences. A relative newcomer to that mix is the social network Pinterest, which enables followers to post photos and other types of visuals based on topics of interest. A content analysis examined how 85 local television stations are using that social network for promotion and branding. Results showed that, rather than promotion, use of Pinterest primarily revolves around lifestyle content, including postings by stations and interactivity by followers.  相似文献   
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Most companies are under pressure to improve the environmental sustainability of their supply chains. However, there is considerable variance in companies' ability to successfully deploy environmental management projects. One important factor, according to articles in the academic and business press, is the ability of champions of sustainable supply chain management (SCM) projects within organizations to gain the commitment of colleagues (e.g., other managers from a variety of functions) to help these projects succeed. Therefore, this paper examines variables that affect a project champion's ability to gain this commitment from colleagues. In particular, building on existing research, this research employs a video‐based experimental design to examine the effect of the influence approach that the project champion employs, the values of the person the champion is trying to influence, and the organizational climate. The results suggest that organizational climate and certain individual values directly affect commitment. There are also interactions between values and influence tactics. The research adds to the field's growing knowledge on the antecedents of sustainable SCM within companies while providing valuable guidance for environmental champions and for top managers.  相似文献   
204.
This paper investigates volatility spillover in the Nigerian sovereign bond market arising from oil price shocks, using Vector Autoregressive Moving Average ‐ Asymmetric Generalized Autoregressive Conditional Heteroscedasticity (VARMA‐AGARCH) model. The paper covers the period March 22, 2011 to April 14, 2016 and makes use of the daily data of the Nigerian Sovereign Bond, Brent oil and West Texas Intermediate (WTI), respectively. We endogenously and sequentially detect structural break points using the test of Bai and Perron (2003) framework. In order to accurately estimate the model, we modify it by incorporating the break points into the VARMA‐AGARCH model, a process which if ignored would lead to model misspecification. The results obtained demonstrate a significant cross‐market volatility transmission between oil and sovereign bond market with ample sensitivity to structural breaks. The study also computes optimum weight portfolio and hedge ratio both with and without structural breaks and results equally indicate sensitivity to structural breaks.  相似文献   
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Financial Markets and Portfolio Management - As symbolized by vacant office buildings, empty shopping malls and abandoned flats in metropolitan areas, the new coronavirus disease 2019 has severely...  相似文献   
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This study conducted a large-scale survey in Dhaka, Bangladesh; the survey involved 95 major hospitals, more than 3000 emergency room patients, and 2 of the largest ambulance operators. Currently, most ambulances are parked within the vicinity of hospitals and are either dispatched or fetched by the acquaintances of the patient on demand, resulting in lengthy round trips. Reducing the response time of ambulances would certainly improve the emergency service, and pre-positioning of the ambulances could be a solution to reducing the response time. This study used two approaches to address the problem. First, the location-allocation problem was solved to find the optimal number of ambulance locations by maximising the demand coverage. Second, separate location-allocation for the peak and off-peaks, using K-means clustering, was applied to systematically optimise the ambulance positioning in small clusters near demand points. These approaches could substantially improve the existing emergency response time. Distributing ambulances near demand points yielded greater improvements in response time than when the ambulances are stationed near hospitals.  相似文献   
209.
At a theoretical level this article discusses Piketty’s hypothesis that the distribution of income and wealth tends to become more concentrated over time when the rate of return on capital is greater than the growth rate of real output. We develop a post Keynesian model of growth and distribution showing that once capital is differentiated from wealth, the increase in income and wealth concentration actually occurs when the rate of valorization of financial and real estate assets is greater than the growth rate of real output, and that this situation may be triggered by financial liberalization.  相似文献   
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Making architectural decisions in long lifecycle systems is challenging because the time between system definition and end of operations can span multiple decades, resulting in shifts in stakeholder needs and major advances in technologies. Space-based communications using relay satellite constellations is one such example, requiring substantial up-front planning to define capabilities and size capacity due to the large investment of time and resources. Additionally, there are numerous viable system architectures. In this paper, we build on existing methods to develop a graph-based decision method to assess and explore architectural flexibility in the future evolution of long lifecycle systems. The tradespace graph defines edges between similar architectures, quantifies the switching cost between architectures, using graphs to analyse the potential system evolution pathways. In a test case on NASA communication satellites, we find that hosting government communications payloads, in particular optical payloads, on commercial satellites could reduce cost and increase flexibility of the NASA network.  相似文献   
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