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81.
Jackeline Rios-Torres Jun Liu Asad Khattak 《International Journal of Sustainable Transportation》2019,13(2):123-137
Improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To do this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed. 相似文献
82.
Destination image is influenced by many factors, including destination promotion materials, the mass media as a general familiarity agent, the perceivers’ own characteristics and even researchers’ methodological choices. To isolate and minimize the impact of research on destination image, different qualitative and quantitative designs and analysis techniques have been utilized. However, no previous study utilized the network analysis technique, which may be useful to reveal a picture of destination image with the interconnections and hidden dynamisms of dimensions as well as its correlates. The present study applies this technique on qualitative data from an online sample of Americans on their perceptions of a relatively remote and unfamiliar destination, the Caucasus region, in order to hone in on the dramatic impact of mass media on destination image. Results revealed networks of meanings with residue of mass media messages about Boston bombing, with some differences among different genders and education levels. 相似文献
83.
We explore the relationship between inequality and entrepreneurial activity. Drawing on cross-sectional data from a largescale survey of the economic conditions of individuals across India, we develop a number of dimensions of inequality to explore empirically how inequality interacts with entrepreneurship, operationalized as self-employment or as employing other people. We find compelling evidence that there are thresholds to becoming self-employed, and even more so to assembling the combinations of resources and personal attributes required to become an employer. Greater inequality leaves more people unable to make the transition to self-employment, leaving casual laboring as the occupation of necessity. At the same time, inequality increases the number of employers in a society, by concentrating resources - particularly land and finance - enough for significant numbers of people to be able to cross this higher threshold. Lastly, greater differentiation into social or religious groups curtails the ability to cross either entrepreneurial threshold, presumably by limiting the extent and benefits of social networks of value for entrepreneurship. 相似文献
84.
Christopher Ambrey Matthew Bitzios 《International Journal of Sustainable Transportation》2018,12(10):737-752
This study investigates the correlates of a resident's walking behaviors and aims to shed light on mechanisms through which walking may be encouraged. The results of this investigation paint a complex and nuanced picture of the residents’ walking behaviors in South East Queensland, Australia. The results suggest that sociodemographic characteristics separately may contribute greatly to whether or not one engages in walking behaviors. Further, cumulatively these differences might be greater for some groups of residents compared to others. One of the most prominent findings of the study is that the purpose, the characteristics of the origin, and the characteristics of the destination of a trip tended to be similar in the heterogeneity they exhibit over the distribution of time spent walking. For example, pick something up, undertake work, or engage in personal business, move to or from a workplace, shop, or social place are activities that tend to be associated with walking as a main mode of transport and a higher number of walking episodes. However, these trips tended to be short. 相似文献
85.
针对机载三维音频应用的实时性需求,提出了一种基于单耳相对头相关传递函数和改进型混响模型的机载三维音频快速实现方法,在较传统实现方式性能无明显下降的情况下降低了80%的计算量。对提出的算法在F-16战斗机模拟强噪声环境下进行相关主观试听实验,同时在某型飞机音频系统中实验验证。实验结果表明,所提方法在实时处理3路三维音频时,三维音频方位分辨精度在5°以内,可满足实际机载平台使用需求。 相似文献
86.
This research looks into the innovative activities of subunits of large non-U.S firms in the U.S from 1969 to 1995, suggesting that the innovations in the subunits of multinational corporations are closely linked to their specializations in General Purpose Technologies (GPTs). GPTs enable recombining knowledge from different domains on an international scale, and that the specialization of innovations in GPT fields within a subunit is positively associated with the innovative capacity at large, along with the degree of technological diversification of that specific subunit. As firms expand geographically to tap into local innovation centers to develop new growth alternatives, specialization of GPTs in these firms actually facilitates further geographical dispersion of innovative activities across locations. Lastly, additional specializations of innovations in GPT fields within the host innovation centers does help in attracting innovation activities of firms from a wider range of industries. 相似文献
87.
Even when the neoliberal ideology of the free market was more dominant than it now is, the state was involved in economic activities that could be undertaken by private firms. State capitalism takes increasingly diverse forms, including beyond direct, partial or even indirect ownership. This paper briefly reviews some of these forms without claiming to be exhaustive as the shape state capitalism takes differs widely across the institutionalized contexts of countries. We assess state capitalism using Polanyi’s double movement framework and argue that this framework needs adaptation to novel forms of state capitalism that include, e.g., state-owned multinationals and sovereign wealth funds. 相似文献
88.
Linnea Haag Uni Sallnäs Erik Sandberg 《International Review of Retail, Distribution & Consumer Research》2019,29(3):321-339
ABSTRACTMarket-oriented aspects of retail internationalisation have received a lot of research attention since the 1990s. However, beyond these aspects lies also supply-chain oriented capabilities that are necessary for retailers to successfully internationalise into foreign sales markets. By using a perspective based on resource-based theories, this paper explores supply-chain oriented capabilities that facilitate retail internationalisation. The research is based on a multiple case study of three Swedish retailers. Through the perspective of research based theories, specifically capabilities, the empirical data is studied in a single-case as well as a cross-case analysis. Findings reveal three supply chain-oriented capability categories (leadership capability, integration capability and learning capability) of importance for retail internationalisation. Resources necessary for the capabilities are to be found internally at the retailer, but also externally at other firms. This research adds to the market-oriented knowledge on retail internationalisation by adding a supply-chain oriented perspective. Further, it provides an understanding of the early phases of retail internationalisation. 相似文献
89.
Montakan Chubchuwong 《Asia Pacific Journal of Tourism Research》2019,24(2):168-179
The objectives of this research are firstly, to study the characteristics of CSR activities conducted for international business groups. Secondly, to analyze the factors that impact business travelers’ satisfaction with CSR activities, and thirdly, to analyze the influence of satisfaction with CSR activities on destination attachment and destination loyalty. A questionnaire survey was conducted with 127 business participants from three corporate meetings and one convention group. The results reveal the characteristics of CSR activities of corporate meetings and conventions in Thailand. Business travelers’ satisfaction with CSR activities is influenced by their personal altruistic attitudes and the efficacy of local service providers. Satisfaction with CSR activities has a direct impact on destination attachment and an indirect impact on destination loyalty. CSR activities could be used as tools to influence the revisit intention of corporate meeting and convention participants. A CSR activity during a business trip is a novel concept that can be utilized by destination management companies as well as national tourism organizations to develop satisfying tourism products. 相似文献
90.
在就跨境电商对华商网络贸易所具有的替代效应与互补效应进行理论分析的基础上,利用古诺模型分析市场均衡的结果及贸易效应,采用面板数据实证检验跨境电商对华商网络贸易的影响,结果表明跨境电商对华商网络贸易的互补效应大于替代效应:一方面,由于华商网络对出口贸易的影响尤为显著,而跨境电商平台又以出口贸易为主,从而跨境电商对华商网络出口贸易的影响较大;另一方面,跨境电商平台偏向于差异化产品贸易,因而跨境电商对差异化产品的华商网络贸易有着较大影响。也就是说,跨境电商对华商网络贸易的互补效应在出口贸易与差异化产品贸易上表现得尤为显著。 相似文献