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81.
Governments around the world are adopting inclusive growth agendas. The ambition to align economic growth ambitions with broader-based social benefits is increasingly embraced by corporations to limit the ‘negative externalities’ and enhance the ‘positive externalities’ of their operations. Therefore, micro-level corporate strategies and macro-level national ambitions meet at the meso-level of networks and clusters. This requires societal spheres to collaborate and search for alternative governance constellations. In this discourse, port development is only recently receiving attention. In March 2018, ports around the world signed the World Ports Sustainability Program declaration, which aims to contribute to the sustainable development goals (SDGs), whilst a number of national port (master) plans have started to include social along with environmental standards. Extant studies on partnering and stakeholder inclusion in port development are proliferating but are primarily aimed at environmental rather than social (inclusion) issues. This paper adopts an exploratory research design to consider conditions for inclusive port development. A novel taxonomy considers port development as a driver for inclusive growth, where partnerships are the missing link between micro-level business strategies and macro-level effects in the port region and economy at large. This paper shows the first findings and delineates areas for further research.  相似文献   
82.
Using a dynamic approach, employing data on job mobility, we demonstrate that university workers?? marginal willingness to pay for reducing commuting distance is about ?0.25 per kilometre travelled. This corresponds to a marginal willingness to pay for reducing commuting time of about 75?% of the net average hourly wage. For females, the willingness to pay is substantially higher than for males. It is also substantially higher for workers that work few hours per day, as predicted by theory.  相似文献   
83.
Short-term prediction of travel time is one of the central topics in current transportation research and practice. Among the more successful travel time prediction approaches are neural networks and combined prediction models (a ‘committee’). However, both approaches have disadvantages. Usually many candidate neural networks are trained and the best performing one is selected. However, it is difficult and arbitrary to select the optimal network. In committee approaches a principled and mathematically sound framework to combine travel time predictions is lacking. This paper overcomes the drawbacks of both approaches by combining neural networks in a committee using Bayesian inference theory. An ‘evidence’ factor can be calculated for each model, which can be used as a stopping criterion during training, and as a tool to select and combine different neural networks. Along with higher prediction accuracy, this approach allows for accurate estimation of confidence intervals for the predictions. When comparing the committee predictions to single neural network predictions on the A12 motorway in the Netherlands it is concluded that the approach indeed leads to improved travel time prediction accuracy.  相似文献   
84.
This article presents the results of a study exploring travellers’ preferences for middle-distance travel using Q-methodology. Respondents rank-ordered 42 opinion statements regarding travel choice and motivations for travel in general and for car and public transport as alternative travel modes. By-person factor analysis revealed four distinct preference segments for middle-distance travel: (1) choice travellers with a preference for public transport, (2) deliberate-choice travellers, (3) choice travellers with car as dominant alternative, and (4) car-dependent travellers. These preference segments differ in terms of the levels of involvement and cognitive effort in travel decision making, the travel consideration-set and underlying motivations. The study showed that for most people there is more to travel than getting from point A to point B, and that there is considerable heterogeneity in middle-distance travel preferences. Policy implications for reducing the need for travel and promoting a modal shift from car to other travel modes are discussed.  相似文献   
85.
In this paper we present a novel method to improve the robustness of solutions to the Flight-to-Gate Assignment Problem (FGAP), with the aim to reduce the need for gate re-planning due to unpredicted flight schedule disturbances in the daily operations at an airport. We propose an approach in which the deterministic gate constraints are replaced by stochastic gate constraints that incorporate the inherent stochastic flight delays in such a way so as to ensure that the expected gate conflict probability of two flights assigned to the same gate at the same time does not exceed a user-specified value. The novel approach is integrated into an existing multiple time slot FGAP model that relies on a binary integer programming formulation and is tested using real-life data pertaining to Amsterdam Airport Schiphol. The results confirm that the proposed approach holds out great promise to improve the robustness of the FGAP solutions.  相似文献   
86.
Objective According to the distribution of low selenium areas, low nutrition state of the residents and the affecting cartilage growth and articular cartilage of Kashin-Beck Disease(KBD),the chondrocyte differentia- tion and differential expression of collagen types Ⅰ , Ⅱ and Ⅹ in articular cartilage from Chinese mini-pigs treated with low selenium were investigated in order to gain insight into the effects of these conditions on chondrocyte differ- entiation in KBD cartilage. Mothods Eleven male juvenile mini-pigs, aged from 4 weeks to 6 weeks after birth, were divided into 3 groups. The Se content in the diet of the “low Se” group was 0. 035mg/kg diet, and 0. 175 mg/kg diet in the control. For Se-supplemented group 0. 390mg /kg diet was added. The content of Se in blood was assayed at the beginning and at the end of each experiment. Samples of articular cartilage were taken from the right femur condylus, and collagen types Ⅰ , Ⅱ and Ⅹ in articular cartilage were analyzed by immunohistochemistry and in situ hybridization. Results ①All cartilage samples from juvenile mini-pigs fed with low selenium diet revealed a re- duction in type Ⅹ collagen mRNA expression in the hypertrophic chondrocytes as shown by in situ hybridization, and reduced type Ⅹ collagen deposition in the lower hypertrophic zone as shown by immunohistochemistry. ②Addition of selenium to the diet restored the type Ⅹ collagen to normal level. ③Type Ⅱ collagen was evenly distributed over the entire articular cartilage in all experimental and control groups. Type Ⅱ collagen mRNA signals were most prominent in the upper articular layer as well as in the hypertrophic zone in all groups. Type Ⅱ collagen expression was restrict- ed to the zone of endochondral ossification in all experimental groups and the control. Conclusion Low selenium has an down-regulatory role on the synthesis and deposition of collagen type Ⅹ in hypertrophic chondrocytes in articular cartilage of mini-pigs. Supplement of the low Se diet with additional Se restored the signals of collagen type Ⅹ to nor- mal levels. These findings indicate that selenium deficiency may disturb chondrocyte differentiation to hypertrophic cells in the growth plate,and worthy to be investigated further.  相似文献   
87.
Container barging has gained in importance in port-related transport along with the need for sustainable transport. Nevertheless, coordination problems between terminal operator and barge operator exist, and performance lags behind. This paper analyses factors that may hinder or stimulate a better future performance of container barging in the port of Rotterdam. A case study is accomplished and guided by a framework rooted in Institutional Economics. Despite favourable conditions set by governments and the port authority, the share of container barging has hardly grown. The container barging sector in Rotterdam is embedded in a history with many alliances, a high degree of organisation, and a good track record in the development of institutional arrangements to solve coordination problems. However, the present contractual relations in the transport chain form an inadequate condition. From a theoretical perspective, the paper shows the value of studying port-related transport chains by acknowledging their institutional context.  相似文献   
88.
Bert van Wee 《运输评论》2013,33(3):279-292
Abstract

In the last decade the importance of attitude‐related residential self‐selection has frequently been recognized. In addition people can theoretically self‐select them with respect to other location choices, such as job locations, with respect to travel behaviour, or with respect to the exposure to transport externalities such as noise and congestion. In this paper, we argue that insights into self‐selection processes might significantly improve our knowledge on location choices, travel behaviour and transport externalities. We elaborate on options for self‐selection and briefly formulate methodologies for research into self‐selection.  相似文献   
89.
Travel time reliability is considered to be one of the key indicators for the performance of transport systems and is measured in various ways. This paper synthesizes both reliability concepts: traffic breakdown, the indicator of the instability of travel times, is treated as the risk, whereas travel time variability, the indicator of the uncertainty of travel times, is considered as the consequence of this risk. An analytical formula, using risk assessment technique, explicitly expresses the cost of travel time unreliability as the sum of the products of the consequences (i.e. variability) and the corresponding probabilities of breakdown. It provides a novel measure of travel time reliability and is applicable in network performance evaluations. An empirical example based on a large dataset of freeway traffic flow data from loop detectors shows that the developed travel time reliability measure is both intuitively logical and consistent.  相似文献   
90.
The literature on car cruising is dominated by theory. We examine cruising for parking using a nation-wide random sample of car trips. We exclude employer-provided and residential parking. We focus on the Netherlands, where levels of on-street and off-street parking prices are locally the same. We demonstrate then that due to this price setting the average cruising time in the Netherlands is only 36 s per car trip. Furthermore, we show that cruising is not random. It is more common in (large) cities that receive more car trips, particularly for shopping and leisure activities. Cruising time increases with travel duration as well as with parking duration. Cruising has a distinctive pattern over the day with a peak in the morning, so the order of arrival is essential to parking. Because cruising has a spatial and time component, policies may be considered that reduce cruising time through flexible pricing of parking or improved information about vacant parking spaces.  相似文献   
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