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71.
ABSTRACT

Information accuracy and decision-making speed are of paramount importance in managing today’s mobility of goods and people inside the city. Intelligent Transport Systems (ITS) can provide road users with updated information and forecasts on both traffic and weather conditions. The result is a higher efficiency in the use of resources and a better management of physical flows. The purpose of this paper is to conduct an in-depth review on the role of ITS supporting urban Smart Mobility, in order to identify the main gaps in the literature and propose future research streams. In total, 71 papers have been thoroughly analysed: they are mainly focused on technology, with limited attention to value creation. Even though some benefits have been examined, a general lack of quantitative models emerged. Eventually, there is a lack of contributions considering both people and freight transport, even if they are strongly related, especially in an urban environment.  相似文献   
72.
Products of random variables are of both practical and theoretical significance to social scientists. This has increased the need to have available the widest possible range of statistical results on products of random variables. In this note, the distribution of the product XY is derived when X and Y are independent Fréchet random variables. Extensive tabulations of the associated percentage points are also given.  相似文献   
73.
In this study we propose a mathematical definition of the consumption efficiency of multi-attribute products in the price–quality space. A new model, the discrete Range Adjusted Measure (RAM) model, is suggested as an empirical tool to measure the level of consumption efficiency. We further discuss the effect of consumption efficiency on the innovation incentive. Empirical work is made for the mobile phone market. We expect that the consumption efficiency concept will contribute to the extension of the traditional framework of production efficiency analysis on the one hand and to the understanding of the nature of innovation in a technology-intensive market on the other hand.JEL Classification: C67, D11, D12, D21  相似文献   
74.
李菡芳 《价值工程》2005,24(6):56-57
可靠性理论中的核心概念“可靠度”在数值分析时,可以作为价值工程中“功能”相当的量纲。为保证贵重药品生产不间断而决策“贮备系统”的例子表明,可靠性理论和价值工程的结合能产生相当良好的效果。  相似文献   
75.
This paper applies Kim and Wardes (2004) stratified Warners randomized response model to Mangat and Singhs (1990) two-stage randomized response model. The proposed stratified randomized response model has an optimal allocation and a large gain in precision. Hence, the estimator based on the proposed method is more efficient than Kim and Wardes (2004) and Mangat and Singhs (1990) estimators under the conditions presented in both the case of completely truthful reporting and that of not completely truthful reporting by the respondents.  相似文献   
76.
Increased competitions for water resources in many regions worldwide call for cooperative approaches. The competitions are complex for humans to resolve due to numerous alternatives and different or conflicting preferences of multiple stakeholders over multiple criteria, which might even oppose desirable environmental objectives. Parties also have incomplete information about the preferences of the counterparties. Electronic negotiation, empowered by intelligent agent technology, is a combination of artificial intelligence, economics, and psychology to find beneficial joint agreements in complex paradigms such as this. This study investigates a multilateral sustainable automated negotiation among intelligent agents representing stakeholders, including the legal party ‘nature’ as one of the stakeholders. It defines decision criteria and alternatives in the framework of cultural factors, elicits preferences of the stakeholders regarding the criteria without their intervention using a multi-criteria decision-making method, prunes the solution space before starting the negotiation by recognizing a general social treaty, determines the multi-issue specific treaty by learning the stakeholders, and demonstrates bidding and acceptance strategies.  相似文献   
77.
With the development of an MCMC algorithm, Bayesian model selection for the p 2 model for directed graphs has become possible. This paper presents an empirical exploration in using approximate Bayes factors for model selection. For a social network of Dutch secondary school pupils from different ethnic backgrounds it is investigated whether pupils report that they receive more emotional support from within their own ethnic group. Approximated Bayes factors seem to work, but considerable margins of error have to be reckoned with.  相似文献   
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In this article we apply univariate and panel Lagrange Multiplier (LM) unit root tests with one and twostructural breaks proposed by Lee and Strazicich (2003, 2004) and Im et al. (2005) to examine housing prices for five different housing price indices (all housing, detached housing, semi-detached housing, terrace housing and high-rise housing) in 14 states of Malaysia to test whether housing prices exhibit a random walk. Our main finding from the univariate LM unit root tests is that for the vast majority of states housing prices follow a stationary process about a segmented trend. The results of the panel LM unit root tests provide overwhelming evidence that house prices are segmented trend reverting.  相似文献   
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