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81.
CHETAH, which stands for the Chemical Thermodynamic and Energy Release Program, was introduced in 1974. Since then, the CHETAH program has been widely used in the chemical industry for hazard evaluation. Although its chief aim is to predict deflagration/detonation potential from molecular structure, it can also be used to estimate heats of reaction, heat capacities, and entropies. One of the limitations of the original program was its rigid, punched card oriented format for data input and the lack of an overall hazard rating derived from the several hazard criteria. A new release of this program alleviates these shortcomings and includes other improvements. The main features of the new release are: 1) a totally interactive front end, 2) an interpreter subroutine which uses sophisticated pattern recognition techniques to combine the four hazard criteria into an overall hazard rating, 3) recognition of certain atomic groupings which are known to be sensitive, 4) correct handling of the symmetry number, and 5) an updated data bank. One of the most important features of this release is its availability in an IBM PC compatible version, making the program accessible to more users.  相似文献   
82.
The paper mathematically develops the heuristic idea that the first-order necessary conditions for a classical constrained optimization problem are equivalent to a market being arbitrage-free - with the Lagrange multipliers being the arbitrage-free market prices. The arbitrage notions start with the multiplicative Kirchhoff's Voltage Law and then generalize to matrix algebra. The basic result shows the normalized arbitrage-free «market prices» (the Lagrange multipliers) resulting from a classical constrained optimizaton problem can always be obtained as a ratio of cofactors. The machinery also gives an economic interpretation of Cramer's Rule as a competitive equilibrium condition.  相似文献   
83.
In this editorial, we reflect on how the Journal of Sustainable Tourism can contribute towards sustainable tourism researchers achieving more impact with their research. We propose some changes that can be tested in, and introduced gradually and collaboratively with, the community of the editorial board and authors. To support impactful mind sets, we will promote research that reflects diverse academic communities. To promote impactful research topics, we will encourage authors to frame their submitted articles against the Sustainable Development Goals, while research that is time sensitive will be fast tracked so it can contribute to current debates. To promote impactful methodologies, we shall favour articles that use mixed methods and action research, and those that conduct longitudinal, experimental, and evaluative research. To promote impactful partnerships, we will favour multidisciplinary approaches and research that has been co-created with stakeholders. To promote impactful communication and dissemination, we will continue to build an online community on social media for sustainable tourism researchers, we will promote articles in social media to raise their visibility, and we will provide free access to those articles that are deemed to have the greatest potential to impact positively on society.  相似文献   
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Recent policy from the European Union has attempted to justify social tourism initiatives on the basis that they lead to a more sustainable tourism industry. However, the majority of latest research in the field has been focused on the benefits for participants, with the addition of some evidence on the economic impacts of such programmes on destinations, which have pointed towards sustainability outcomes including: a longer tourism season, more even spread of demand, and longer periods of employment for tourism workers. Yet there is a lack of direct evidence linking such programme to these outcomes. This paper aimed to explore this important disconnect between policy assumptions and evidence-based outcomes through an analysis of the deseasonalising effects of the Spanish social tourism programme for older people. The research found that this programme does have an effect on the seasonal nature of employment and economic activity in most regions studied, but that the huge volume of demand from international tourists in the high seasons masks the quantitative effects in the regions with the highest seasonal concentration of international tourists. Recommendations for policy and practice in sustainable tourism are made that are transferable to many countries and regions that adopt social tourism programmes.  相似文献   
86.
We propose a measure of business risk in air travel demand at the route level that can reduce information asymmetry during route development negotiations between tourism destinations and airlines. Aviation-exposed risk (AER) conveys information about the level of uncertainty with regard to air travel demand from an airline’s perspective. Using AER, tourism destinations and air service development teams can evaluate their risks from the perspective of the airline and its network. From there, an assessment can be made as to the value of air services in certain circumstances, including whether a direct underwrite or risk share between airlines and destinations is viable and necessary. By applying a portfolio analysis to an airline’s network, we find evidence that AER does indeed mimic the actual capacity distribution of the network. This provides support for AER as a useful risk measure to be used in practice.  相似文献   
87.
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   
88.
Personalisation refers to individualizing products, services, and contents according to customer interests and preferences. In order to deliver appropriate personalised offerings, firms inevitably need to collect rich customer data profiles. Prior research suggests that personalised services lead to positive customer responses such as increased willingness to disclose personal information and make purchases. However, another stream of research emphasizes negative outcomes of personalisation – namely, privacy concerns surrounding the use of personal information and associated negative effects on behaviour. The objectives of this study are twofold: (1) to examine how privacy assurance affects proximal outcomes of personalisation, such as perceived usefulness and privacy concerns; and (2) to identify the role such outcomes play in predicting customer behavioural responses, such as willingness to disclose personal information and make purchases. Our findings show that enhancing privacy assurance increases the perceived usefulness of services and decreases customer privacy concerns. Moreover, customer behavioural responses are positively related to the perceived usefulness of services and negatively associated with privacy concerns. However, despite the positive effects on perceived usefulness and purchase intentions, personalisation has no effect on privacy concerns and intentions to disclose personal information.  相似文献   
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