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931.
在调研与分析的基础上,提出了洞庭湖大桥桥头公园和桥头建筑设计的立意与构思,强调建筑设计与人文景观高度结合,建筑设计与桥梁本身的力度美高度结合,建筑设计应该具有自然美等为设计的指导思想,从而使设计方案在竞标中取胜。  相似文献   
932.
提出电子客票在中国铁路旅客运输中的应用设想,分析了铁路电子客票的应用意义,并给出电子客票应用的发展策略.  相似文献   
933.
Encouraging pro-environmental behavior among protected area visitors and other stakeholders has become a priority for marine resource managers. However, there exists a lack of understanding of the human dimensions of resource management regarding the perceptions and attitudes of stakeholders. Using the value-belief-norm theory of environmentalism (VBN) as a framework, the purposes of this investigation were to: 1) test a model of variables that influence stakeholders' intentions to adopt pro-environmental behavior in two marine protected areas (i.e., the Great Barrier Reef Marine Park and the Florida Keys National Marine Sanctuary); and 2) using the relevant literature and information gleaned from the model, suggest techniques that managers can use to encourage pro-environmental intentions. Acceptable goodness-of-fit indices for both of the structural equation models (one for each protected area) provided empirical support for the usefulness of the VBN framework to guide both research in marine contexts and marine protected area management efforts to encourage stakeholders' intentions to engage in pro-environmental behavior. Specific suggestions include increasing stakeholders. knowledge about impacts via environmental education strategies, increasing their awareness of their impacts and their efficacy in mitigating those impacts (e.g., workshops), and developing interpersonal relationships among managers and stakeholders (e.g., implementation intention and follow-up strategies).  相似文献   
934.
Transportation - Given the limitations of traditional methods of data collection and the increased use of smartphones, there is growing attention given to using smartphone apps for activity-travel...  相似文献   
935.
乐毅成  刘相乾 《船电技术》2011,31(8):33-34,15
以乙酰乙酸乙酯和芳甲酰氯为原料,合成相应的β-酮酸酯,在乙醇钠/碘的作用下实现二聚偶联反应得到1,4-二酮化合物,然后与水合肼反应,得到两个新型含1肺吡唑的双杂环化合物,其结构经’HNMR、Ms及IR证实。  相似文献   
936.
[Objective]To simplify the ship modeling process and improve modeling efficiency, this paper proposes a method for rapidly implementing hull model creation based on hull line drawing.[Methods]Using the CATIA platform, this method adopts the component application architecture (CAA) development tool for secondary development. First, by reading the geometry elements and label information of the hull lines in a drawing, the transformation of the offset points from 2D to 3D is realized. On this basis, the creation of the hull lines, stern and bow is completed, and a 3D wireframe model obtained. Finally, the hull 3D modeling is completed in conjunction with the CATIA native surface creation command. The stability and reliability verification of the developed type value extraction and bow generation program is then carried out via application analysis.[Results]The results show that the compiled program can realize the automatic creation of offset points, transverse lines, waterlines, profile lines and other boundary lines except the top line of the wall, and the centerline and tangent lines created by the bow generator are easily modified and simple for users to operate. [Conclusions]The verification results show that the method of a creating hull model using "Generative Shape Design" and "Drafting" with the hull line drawing as the data input is stable, reliable and able to realize rapid hull modeling, giving it certain practical value. © The Author(s) 2022.  相似文献   
937.
This paper investigates a strategic signal control, which anticipates travelers' route choice response and determines signal timings to optimize network‐wide objectives. In general traffic assignment models are used for anticipating this route choice response. However, model‐reality mismatch usually brings suboptimal solutions to the real system. A repeated anticipatory control resolves the suboptimality and addresses the modeling error by learning from information on model bias. This paper extends the repeated control approach and focuses on the estimation of flow sensitivity as well as its influence on control, which is a crucial issue in implementation of model bias correction. The main objective of this paper is first to analyze the estimation error in the real flow derivative that is estimated from noisy measurements. A dual control method is then presented, improving both optimization objective function and derivative estimation during the control process. The proposed dual algorithm is tested on a simple network as well as on a midsize network. Numerical examples confirm the reliable performance of the new reality‐tracking control strategy and its ability to identify (local) optimal solutions on real traffic networks. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
938.
This paper aims to evaluate the influence of policies, attitudes and perceptions when incentivizing alternative fuel vehicles. The impact of possible policies such as gasoline taxes increases, purchase price subsidies, tax exemptions, and increases in fuel recharging station availability for alternative fuelled vehicles is evaluated using hybrid choice models. The models also allow assessing the sensitivity of latent variables (i.e., attitudes and perceptions) in the car purchase behaviour. The models are estimated using data from a stated choice survey collected in five Colombian cities. The latent variables are obtained from the rating of statements related to the transport system, environmental concern, vehicle preferences, and technology. The modelling approach includes regression between latent variables. Results show that environmental concern and the support for green transport policies have a positive influence on the intention to purchase alternative fuel vehicles. Meanwhile, people who reveal to be car-dependent prefer to buy standard fuelled vehicles. The analysis among cities shows similar trends in individual behaviour, although there are differences in attribute sensitivities. The policy scenario analysis revealed high sensitivity to capital cost and the need for extensive investments in refuelling stations for alternative fuel vehicles to become attractive. Nevertheless, all policies should not only be directed at infrastructure and vehicles but also be focused on user awareness and acceptance of the alternative fuel vehicles. The analysis suggests that in an environmentally conscious market, people prefer alternative fuels. However, if the transport policies support private transport, the market shares of alternative fuel vehicles will decrease.  相似文献   
939.
The execution of vandalism and graffiti on rail property has a significant impact on rail authorities, the patronisation of rail services, expenditure, and the timely operation of services. There are also important social costs which stem from passengers feeling unsafe, not to mention the environmental costs of removing graffiti and repairing vandalism. In this review paper, we focus on the social, non-technical determinants of and deterrents to vandalism and graffiti in the rail industry. First, we consider the definitions of graffiti and vandalism that are often conflated. After providing some clarification on terminology, and proposing a media-centred approach to vandalism and graffiti, we consider various theorisations of the psychosocial determinants of vandalism and graffiti behaviour. We then turn to an empirical discussion of different technical and social, non-technical prevention programmes that have been trialled. With a focus on identifying what works and under what circumstances, we refer to international case studies of successful vandalism reduction initiatives from Europe, the United Kingdom, the United States of America and Australia. Based on a review of literature and practice, we outline a future research agenda to address vandalism and graffiti. We recommend lines of further research covering: theory, empirical data collection and practical initiatives. Specifically, we note the need for a trans-theoretical model of vandalism and graffiti, further ethnographic research and improved evaluation and benchmarking strategies. This is the first review dedicated to the topic of vandalism and graffiti in the rail industry and the first review of non-technical, social deterrents to vandalism and graffiti broadly.  相似文献   
940.
We explore whether experts’ perceptions of risk differ systematically from those of the public. To do so, we examine whether experts and non-experts make different location decisions in response to ground-level ozone pollution, one of the byproducts of motorized transportation. Physicians are experts in the field of health, and thus may differ from their lay neighbors in their knowledge of and attitude toward pollution and its health risks. If so, it is possible that they value locations with cleaner air differently than their neighbors do. Here we use hedonic price models based on willingness to bear housing and commute burdens to examine the differential valuation of clean air by doctors and laypeople in the Los Angeles region between 1980 and 2000. We find no evidence that doctors are more or less more willing than comparable lay residents to trade off time or money to live in cleaner-air neighborhoods.  相似文献   
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