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81.
The paper estimates an aggregate daily water demand for Sydney using rainfall, temperature, and price data from 2001 to 2005, and a dummy variable to account for reductions in demand following the introduction of water restrictions in October 2003. Analyses based on the estimated price elasticity, and also values one and two standard errors above and below this estimate, are used to model the effects of different pricing and water supply scenarios. The simulations indicate that without a fundamental change in water policy (pricing and supply) Sydney faces the possibility of critical water shortages in the short- to medium-term should there be a continuation of low rainfall events.  相似文献   
82.
During many manmade and natural crises such as terrorist threats, floods, hazardous chemical and gas leaks, emergency personnel need to estimate the time in which people can evacuate from the affected urban area. Knowing an estimated evacuation time for a given crisis, emergency personnel can plan and prepare accordingly with the understanding that the actual evacuation time will take longer. Given the urban area to be evacuated, street widths exiting the area's perimeter, the area's population density, average vehicle occupancy, transport mode share and crawl speed, an estimation of traffic evacuation time can be derived. Peak-hour traffic data collected at three, midblock, Mumbai sites of varying geometric features and traffic composition were used in calibrating a model that estimates peak-hour traffic flow rates. Model validation revealed a correlation coefficient of +0.98 between observed and predicted peak-hour flow rates. A methodology is developed that estimates traffic evacuation time using the model.  相似文献   
83.
Scholars in our field, Operations and Supply Chain Management (OSCM), are under high pressure to show research productivity. At most schools, this productivity is measured by the number of journal articles published. One possible response to such pressure is to improve research efficiency: publishing more journal articles from each data collection effort. In other words, using one dataset for multiple publications. As long as each publication makes a sufficient contribution, and authors ensure transparency in methods and consistency across publications, generating more than one publication from one data collection effort is possible. The aim of this Notes and Debates article, however, is to draw attention to inappropriate reuse of empirical data in OSCM research, to explain its implications and to suggest ways in which to promote research quality and integrity. Based on two cases of extensive data reuse in OSCM, eighteen problematic practices associated with the reuse of data across multiple journal articles are identified. Recommendations on this issue of data reuse are provided for authors, reviewers, editors and readers.  相似文献   
84.
The organizational design literature strongly supports the notion of “structure follows strategy”, and suggests that a misfit between the two has a negative effect on performance. Building on this line of argument, we examine to what extent the (mis)fit between purchasing strategy and purchasing structure impacts purchasing performance. We focus on cost and innovation purchase category strategies, and examine how the deviation from an ideal purchasing structure defined along three dimensions (centralization, formalization, and cross-functionality) impacts purchasing performance. Analysing data collected from 469 firms in ten countries, we demonstrate that a strategy-structure misfit negatively impacts purchasing performance in both cost and innovation strategies. We also find that purchasing proficiency is a mediator in this relationship between misfit and performance. Our findings aid managerial decision making by empirically validating the necessity of having the right purchasing structure for successfully executing different purchasing strategies.  相似文献   
85.
Vertical specialization (VS) is quantified by the VS share, which measures the average import content per dollar of exports. A characteristic of China’s export trade is its strong dependence on assembly and processing activities. To take proper account of this, China’s VS shares should explicitly distinguish processing export production from other production. We estimate China’s annual VS shares from 2000 to 2012—the latest year for which a special input–output table is available that makes such an explicit distinction. We find that VS shares increased from 2000 to 2004 and subsequently started to decrease. To explore why it has declined, we introduce a new structural decomposition approach. We find that the decrease of the VS share appears to have been driven mainly by the substitution of imported intermediates by domestic products. This occurred in particular in the production of exports, which implies an upgrading of China’s position in global value chains.  相似文献   
86.
Erik Koenen 《Publizistik》2018,63(4):535-556
In the discussion about the future of communication and media science in digital times, this article focuses on the position and perspective of communication and media history. The challenges, problems and potentials associated with digitization are illustrated using the example of historical press research. Within the media ensemble of classical mass communication, the periodic press in particular benefits from the retrospective digitization of historical media and their digital edition in databases and portals. For historical press research, digitized newspapers and digital newspaper portals represent an originally new, because increasingly digital research situation: Digital newspaper portals as a novel, originally digital world for newspapers not only facilitate the path to newspapers and their contents, they also open them up as digital resources machine-readable and thus open up completely new paths for research—not least supported by digital methods.The main objective of this article is to discuss the epistemological-methodological problems and the practical operationalization of digitally framed or supported research processes in historical press research and to present concrete perspectives of knowledge and research strategies for practice. With this aim in mind, the paper discusses three points:(1.) Methodological and practical consequences of historical press research in digital research environments. With the digitization of newspapers and their digital reproduction in newspaper portals, their source character shifts essentially in three dimensions: They are edited and indexed digitally and their complete content is made accessible through optical character recognition. This makes previously unimportant technical aspects such as data formats, portal interfaces, search algorithms and programming interfaces very relevant for the methodology of historical press research. A primary methodological effect of the digital reorganization of newspapers in data and portals is the reversal of the usual reading practice: from “top down” to “bottom up”. With the help of “keyword searching”, newspapers can now be searched comprehensively and transversely to the order of the newspaper original. Nevertheless, there is a warning against an all too naïve and uncritical usage of digitized newspapers and newspaper portals. In practice, some problems and risks are crucial for the conception of historical newspaper research in digital research environments: Besides a hardly standardized and in large parts “wild”, because often uncoordinated and selective digitization of newspapers, the newspaper portals are different in their conception as well as characterized by different content, technical, legal and entrepreneurial conditions.(2.) Historical newspapers as digital sources in practice. The methodological and technical framework are fundamental and far-reaching for the further practical use of newspapers as digital sources in research. In each research step, it must be considered that digitized newspapers are genuinely new and, depending on the quality and depth of digitization, very complex sources with information gains and losses compared to the originals. Newspapers are not simply digitized, they are digitally constructed and differ in this construction from each other. In this respect, historical press researchers are increasingly becoming “users”. However simple and uncomplicated newspaper portals may be in practice, one must incorporate the implicit functions (hidden in algorithms, data and code) and the limits of these knowledge engines and their “correct” use into the research process. Combining and mediating classical hermeneutic methods with search technologies is an essential moment in the practical handling of digitized newspapers.(3.) Historical press research and digital methods. In the light of the new research situation which is emerging with digitized newspapers and newspaper portals, it is obvious that historical press research should increasingly open up to the possibilities of digital methods. In the digital method discussion of historical press research, one concept in particular forms a central point of reference: Franco Moretti’s concept of “Distant Reading”. Basically, “Distant Reading”—and this is what makes this perspective so interesting for historical press research in dealing with the considerable metadata and full text volumes of digitized newspapers—is about the quantitative-automatic indexing of large text corpora using methods and techniques of “Text Mining”. Digital text methods are thus seriously changing the way we look at texts and the research practice with texts such as newspapers: In parts, they automate and accelerate reading processes, produce “new” text extracts by the computer, generate new interpretation contexts between individual text, corpus and condensate, and thus set new orientation points for “close reading”. Computers and digital text methods thus do not relieve researchers of interpretation. Rather, they constantly challenge them to interpret in a continuous interplay in order to give meaning to the text patterns discovered by machines.In spite of all these advantages, digital methods have so far only been used sporadically in historical press research. For this reason, finally a digital workflow for research processes in historical press research will be presented, which illustrates and summarizes essential challenges, problems, solutions and potentials of digitally framed or supported research in press history.  相似文献   
87.
If teachers are not equipped to teach Technology Education subject nationally and internationally, the continent of Africa will continue to bear the brunt of unsavoury results unless radical interventions are implemented to transform the situation. It is against this background that action research methods became a useful site-based support to empower Technology teachers at three sampled schools from Tshwane South Circuit in Gauteng Province of South Africa. The purpose of this study was to share fresh perspectives on how a sample of Technology teachers responded to content-related classroom practices during reflective action research activities that took place during community engagement contact sessions. These teachers, who are under qualified and unqualified to teach this subject, were engaged in circular and spiral action research cycles. The teachers’ engagement brought forth the development of Technology Education Cascading Theory. It was evident that community engagement activities served as a podium to transform teachers’ teaching of Technology Education and enhance learners’ achievement. The study was underpinned by cooperative enquiry theory and engaged participants in reflective practices of developmental action paradigm. Interaction with Technology Education teachers further revealed that most of them need their schools to budget for this Technology subject they are teaching.  相似文献   
88.
Wildlife tourism is a huge global market, the revenue from which can promote local livelihoods and tourist education, enact conservation, and improve animal welfare. Such benefits arise if wildlife tourist attractions (WTAs) prioritise ethical deliverables above financial profit, but recent work has shown that the majority of WTAs have substantial negative animal welfare and conservation impacts. In the absence of global regulatory authorities, tourist revenue has become the ultimate arbiter of what constitutes acceptable use of animals in WTAs. Tourists, however, are not adequate assessors of WTAs’ animal welfare and conservation impacts: they lack the specialist knowledge required and are subject to a number of psychological biases that obscure the ethical dimensions of decisions to attend particular WTAs. This inadequacy is evidenced, and compounded, by overwhelmingly positive reviews on TripAdvisor (the industry-leading review site), even for WTAs with objectively poor ethical standards. Our suggested solution is to empower tourists by presenting unequivocal assessments of WTAs' animal welfare and conservation impacts, hosted in the fora that tourists already use to make their travel decisions. We would thereby promote a subjective norm that tourists should consider and limit their individual negative impacts when choosing which WTAs to visit.  相似文献   
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