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1.
近年来,世界各国及地区老龄化进
程进一步加快,各界学者基于此纷纷展开应
对老龄化问题的理论与实证研究。中国是世
界上老龄人口最多的国家,其中大陆地区将
于2021年起正式步入加速老龄化阶段,并将
于2027年进入老龄社会。在诸多城市公共服
务系统中,交通系统较早面临老龄化影响,
然而中国大陆对于改善老年人出行的理论与
实践研究明显不足,适老出行设施配置与服
务供给严重短缺、相关专项规划和保障政策
长期滞后。基于大陆现阶段适老交通问题,
通过深入探讨我国台湾地区、新加坡以及日
本适老交通的经验,总结了包括完善相关政
策法规、加强公交系统建设、改善慢行出行
环境等启示性经验与措施,为更好应对我国
加速老龄化现状以及老龄化社会适老交通
提供思路。 相似文献
2.
3.
Here a new model of Traveling Salesman Problem (TSP) with uncertain parameters is formulated and solved using a hybrid algorithm. For this TSP, there are some fixed number of cities and the costs and time durations for traveling from one city to another are known. Here a Traveling Salesman (TS) visits and spends some time in each city for selling the company’s product. The return and expenditure at each city are dependent on the time spent by the TS at that city and these are given in functional forms of t. The total time limit for the entire tour is fixed and known. Now, the problem for the TS is to identify a tour program and also to determine the stay time at each city so that total profit out of the system is maximum. Here the model is solved by a hybrid method combining the Particle Swarm Optimization (PSO) and Ant Colony Optimization (ACO). The problem is divided into two subproblems where ACO and PSO are used successively iteratively in a generation using one’s result for the other. Numerical experiments are performed to illustrate the models. Some behavioral studies of the models and convergences of the proposed hybrid algorithm with respect to iteration numbers and cost matrix sizes are presented. 相似文献
4.
Background
Travel practices are changing: bicycle and motorized two-wheeler (MTW) use are rising in some of France’s large cities. These are cheaper modes of transport and therefore attractive at a time of economic crisis, but they also allow their users to avoid traffic congestion. At the same time, active transport modes such as walking and cycling are encouraged because they are beneficial to health and reduce pollution. It is therefore important to find out more about the road crash risks of the different modes of transport. To do this, we need to take account of the number of individuals who use each, and, even better, their travel levels.Method
We estimated the exposure-based fatality rates for road traffic crashes in France, on the basis of the ratio between the number of fatalities and exposure to road accident risk. Fatality data were obtained from the French national police database of road traffic casualties in the period 2007–2008. Exposure data was estimated from the latest national household travel survey (ENTD) which was conducted from April 2007 to April 2008. Three quantities of travel were computed for each mode of transport: (1) the number of trips, (2) the distance traveled and (3) the time spent traveling. Annual fatality rates were assessed by road user type, age and sex.Results
The overall annual fatality rates were 6.3 per 100 million trips, 5.8 per billion kilometers traveled and 0.20 per million hours spent traveling. The fatality rates differed according to road user type, age and sex. The risk of being killed was 20 to 32 times higher for motorized two-wheeler users than for car occupants. For cyclists, the risk of being killed, both on the basis of time spent traveling and the number of trips was about 1.5 times higher than for car occupants. Risk for pedestrians compared to car occupants was similar according to time spent traveling, lower according to the number of trips and higher according to the distance traveled. People from the 17–20 and 21–29 age groups and those aged 70 and over had the highest rates. Males had higher rates than females, by a factor of between 2 and 3.Conclusion
When exposure is taken into account, the risks for motorized two-wheeler users are extremely high compared to other types of road user. This disparity can be explained by the combination of speed and a lack of protection (except for helmets). The differential is so great that prevention measures could probably not eliminate it. The question that arises is as follows: with regard to public health, should not the use of MTW, or at least of motorcycles, be deterred? The difference between the fatality risk of cyclists and of car occupants is much smaller (1.5 times higher); besides, there is much room for improvements in cyclist safety, for instance by increasing the use of helmets and conspicuity equipment. Traffic calming could also benefit cyclists, pedestrians and perhaps moped users. 相似文献5.
6.
国内旅游市场日渐成熟。传统的以游山玩水为主的旅游方式处于衰退趋势,取而代之的是感受自然。了解特色风俗文化。欣赏历史遗迹,这样旅游纪念品就显得尤为霞要。旅游纪念品反映当地文化,传递和表达糟某种信息,旅游者把它带回家.无论是穿的、观赏的还是佩戴的。当再次看见肘都会勾出对旅途的无限回味。目前,我国在旅游纪念品设计开发方面还是薄弱环节。设计师应该结合时代特征更好的开发设计纪念品。 相似文献
7.
This paper describes a stochastic short sea shipping problem where a company is responsible for both the distribution of oil products between islands and the inventory management of those products at consumption storage tanks located at ports. In general, ship routing and scheduling is associated with uncertainty in weather conditions and unpredictable waiting times at ports. In this work, both sailing times and port times are considered to be stochastic parameters. A two-stage stochastic programming model with recourse is presented where the first stage consists of routing, loading and unloading decisions, and the second stage consists of scheduling and inventory decisions. The model is solved using a decomposition approach similar to an L-shaped algorithm where optimality cuts are added dynamically, and this solution process is embedded within the sample average approximation method. A computational study based on real-world instances is presented. 相似文献
8.
Politically-driven climate protection targets call for decarbonization and a massive reduction of total energy consumption by 2050. A comprehensive transformation of existing transport systems and individual mobility is needed to achieve this. There will be no energy transition (“Energiewende”) without a transport transition. Electromobility provides great savings compared to fossil-fueled transport. In addition information and communication technologies (ICT) have become a key factor of innovation and inter- and multimodality. With all structural changes (e.g. industrial restructuring or social change), converting existing organizational forms and mobility evokes conflicts. For example, competing spatial requirements of the energy sector and mobility as well as the exclusion of certain categories of persons are to be expected. Indeed, the transformation process is slowed down by shortcomings in the combination of energy and transport technologies, organizational culture and regulations. A number of questions still remain unanswered. 相似文献
9.
《Ergonomics》2012,55(10):1501-1513
Subjective, physiological and physical performance variables are affected following travel across multiple time-zones (jet-lag). The objective of the study was to examine the effects of oral melatonin in alleviating jet-lag by investigating its effects on subjects who had flown from London to Eastern Australia, 10 time-zones to the east. Melatonin (5 mg day?1) or placebo capsules were administered to 14 experimental (13 males and 1 female) and 17 control subjects (15 males and 2 females), respectively, in a double-blind study; the time of administration was in accord with the current consensus for maximizing its hypnotic effect. Grip strength and intra-aural temperature were measured on alternate days after arrival at the destination, at four different times of day (between the times 07:00 – 08:00 h, 12:00 13:00 h, 16:00 – 17:00 h and 19:00 – 20:00 h local time). In addition, for the first 6 – 7 days after arrival in Australia,subjective ratings of jet-lag on a 0- 10 visualanalogue scale and responses to a Jet-lag Questionnaire (incorporating items for tiredness, sleep, meal satisfaction and ability to concentrate) were recorded at the above times and also on retiring (at about midnight). Subjects continued normally with their work schedules between the data collection times. Subjects with complete data (13 melatonin and 13 placebo subjects), in comparison with published data, showed partial adjustment of the diurnal rhythm in intra-aural temperature after 6 days. A time-of-day effect was evident in both right and left grip strength during adjustment to Australian time; there was no difference between the group taking melatonin and that using the placebo. Right and left grip strength profiles on day 6 were adjusted either by advancing or delaying the profiles, independent of whether subjects were taking melatonin or placebo tablets. Subjects reported disturbances with most measures in the Jet-lag Questionnaire but, whereas poorer concentration and some negative effects upon sleep had disappeared after 3 – 5 days, ratings of jet-lag and tiredness had not returned to ‘zero’ (or normal values), respectively, by the sixth day of the study. Subjects taking melatonin showed no significant differences from the placebo group in perceived irritability, concentration, meal satisfaction, ease in getting to sleep and staying asleep, frequency of bowel motion and consistency of the faeces. These results suggest that, in subjects who, after arrival, followed a busy schedule which resulted in frequent and erratic exposure to daylight, melatonin had no benefit in alleviating jet-lag or the components of jet-lag, and it did not influence the process of phase adjustment. 相似文献
10.
城市规划作为政府对城市空间实施安排和管理的重要公共政策,必须不断提高信息化水平,以智慧化研究手段作为科学决策的基石。但长期以来,规划智慧化发展受制于数据来源、数据质量和分析技术的不足,难以在实际工作中取得革命性突破。文章阐述了手机数据的数据特征、分析方法和手机数据在城市规划领域的基本应用,详细介绍了手机数据分析在无锡市通勤人口分布、居民出行OD、重点区域人口集散特征等方面的应用研究,并对下一步工作做出展望。 相似文献