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31.
音乐是一种富有吸引力的文化旅游资源。对音乐文化资源进行合理的旅游开发可以有效地营造旅游文化氛围,增强旅游地的吸引力,并极大地提高旅游产品的文化品味和游客的旅游质量。文章探讨了音乐文化资源与旅游开发的关系,分析了音乐文化的旅游价值,提出了音乐文化资源旅游开发的措施。  相似文献   
32.
叶蔚忠 《船舶工程》2004,26(5):75-77
针对当前出现的改装船舶价值评估的实际,根据资产评估的一般理论和方法,提出了改装船价值评估的新方法--分段评估法和假想船型法.  相似文献   
33.
氢燃料电池技术有可能为汽车、能源工业带来革命性的变化,毫无疑问会使汽车产业的竞争格局、能源供应方式发生根本变化。汽车产业价值链将出现重大的变革,价值链的核心不再是燃油、燃油发动机,而是氢燃料电池、储氢与供氢系统。本文建立氢燃料汽车价值链模型并进行了分析,氢燃料汽车电池、储氢与供氢系统将是新商业模式最大受益者;燃油、内燃机供应商、传统汽车制造商的前景将不容乐观,相关企业需从新的产业链找到位置和突破口,才能在变革中求得发展。  相似文献   
34.
This paper presents a qualitative assessment of the risk perceptions held by key Australian stakeholder groups in the context of tollroads operated under the public-private-partnership model. The findings confirm that experience accumulated in recent years has contributed toward the betterment of risk-sharing optimisation amongst the contracting parties. The knowledge acquired through in-depth interviews supports the common view that equitable risk sharing is the vital ingredient of value for money. The proposition that the private sector is better equipped to manage commercial risks involving economic decision making whilst risks that have embedded unquantifiable social and public values and those in the domain of public governance are best left with government alone, appears to be replete with refutable implications. Public perception is a malleable concept and should be managed by both sectors.  相似文献   
35.
文章结合国内外采用的橡胶沥青评价体系,采用正交试验法对橡胶沥青材料性能的不同影响因素进行分析,得出橡胶沥青的最佳制备方案。并通过橡胶沥青与基质沥青及SBS改性沥青性能的对比,验证橡胶沥青材料具有明显的优化效果。  相似文献   
36.
Recent methodological advances in discrete choice analysis in combination with certain stated choice experiments have allowed researchers to check empirically the identification of the distribution of latent variables such as the value of travel time (VTT). Lack of identification is likely to be common and the consequences are severe. E.g., the Danish value of time study found the 15% right tail of the VTT distribution to be unidentified, making it impossible to estimate the mean VTT without resorting to strong assumptions with equally strong impact on the resulting estimate. This paper analyses data generated from a similar choice experiment undertaken in Sweden during 2007-2008 in which the range of trade-off values between time and money was significantly increased relative to the Danish experiment. The results show that this change allowed empirical identification of effectively the entire VTT distribution. In addition to informing the design of future choice experiments, the results are also of interest as a validity test of the stated choice methodology. Failure in identifying the right tail of the VTT would have made it difficult to maintain that respondents’ behaviour is consistent with utility maximisation in the sense intended by the experimenter.  相似文献   
37.
We consider a public and congested airport served by airlines that may have market power, and two types of travelers with different relative values of time. We find that in the absence of passenger-type-based price discrimination by airlines, it can be useful to increase the airport charge so as to protect passengers with a great relative time value from excessive congestion caused by passengers with a low relative time value. As a result, the socially efficient airport charge can be substantially higher than what we learned from the recent literature on congestion pricing with non-atomistic airlines.  相似文献   
38.
Priced managed lanes are increasingly being used to better utilize the existing capacity of the roadway to relieve congestion and offer reliable travel time to road users. In this paper, we investigate the optimization problem for pricing managed lanes with multiple entrances and exits which seeks to maximize the revenue and minimize the total system travel time (TSTT) over a finite horizon. We propose a lane choice model where travelers make online decisions at each diverge point considering all routes on a managed lane network. We formulate the problem as a deterministic Markov decision process and solve it using the value function approximation (VFA) method for different initializations. We compare the performance of the toll policies predicted by the VFA method against the myopic revenue policy which maximizes the revenue only at the current timestep and two heuristic policies based on the measured densities on the managed and general purpose lanes (GPLs). We test the results on four different test networks. The primary findings from our research suggest the usefulness of the VFA method for determining dynamic tolls. The best-found objective value from the method at its termination is better than other heuristics for all test networks with average improvements in the objective ranging between 10% and 90% for revenue maximization and 0–27% for TSTT minimization. Certain VFA initializations obtain best-found toll profiles within first 5–50 iterations which warrants computational time savings. Our findings also indicate that the revenue-maximizing optimal policies follow the “jam-and-harvest” behavior where the GPLs are pushed towards congestion in the earlier time steps to generate higher revenue in the later time steps, a characteristic not observed for the policies minimizing TSTT.  相似文献   
39.
This paper proposes a combined usage of microscopic traffic simulation and Extreme Value Theory (EVT) for safety evaluation. Ten urban intersections in Fengxian District in Shanghai were selected in the study and three calibration strategies were applied to develop simulation models for each intersection: a base strategy with fundamental data input, a semi-calibration strategy adjusting driver behavior parameters based on Measures of Effectiveness (MOE), and a full-calibration strategy altering driver behavior parameters by both MOE and Measures of Safety (MOS). SSAM was used to extract simulated conflict data from vehicle trajectory files from VISSIM and video-based data collection was introduced to assist trained observers to collect field conflict data. EVT-based methods were then employed to model both simulated/field conflict data and derive the Estimated Annual Crash Frequency (EACF), used as Surrogate Safety Measures (SSM). PET was used for EVT measurement for three conflict types: crossing, rear-end, and lane change. EACFs based on three simulation calibration strategies were compared with field-based EACF, conventional SSM based on Traffic Conflict Techniques (TCT), and actual crash frequency, in terms of direct correlation, rank correlation, and prediction accuracy. The results showed that, MOS should be considered during simulation model calibration and EACF based on the full-calibration strategy appeared to be a better choice for simulation-based safety evaluation, compared to other candidate safety measures. In general, the combined usage of microscopic traffic simulation and EVT is a promising tool for safety evaluation.  相似文献   
40.
This paper presents an empirical study in investigating user heterogeneity of Value of Time (VOT) and Value of Reliability (VOR). Combined Revealed Preference (RP) and Stated Preference (SP) data were used to understand traveler choice behavior regarding the usage of managed lanes (MLs). The data were obtained from the South Florida Expressway Stated Preference Survey, which focused on automobile drivers who had traveled on the I-75, I-95, or SR 826 corridors in South Florida. Mixed logit modeling was applied and indicated an average value of $13.55 per hour for VOT and $16.13 per hour for VOR. Potential sources of heterogeneity in user sensitivities to time, reliability, and cost were identified and quantified by adding interaction effects of the variables in the mixed logit model. The findings indicated that various socioeconomic demographic characteristics and trip attributes contributed to the variations in VOT and VOR at different magnitudes. The results of this study contribute to a better understanding on what attributes lead to higher or lower VOT and VOR and to what extent. These findings can be incorporated into the demand forecasting process and lead to better estimates and enhanced analytical capabilities in various applications, such as toll feasibility studies, pricing strategy and policy evaluations, and impact analysis.  相似文献   
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