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ON MONOTONE TRAVELING WAVES FOR NICHOLSON'S BLOWFLIES EQUATION WITH DEGENERATE p-LAPLACIAN DIFFUSION
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作者 Rui HUANG Yong WANG Zhuo YIN 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1550-1571,共22页
We study the existence and stability of monotone traveling wave solutions of Nicholson's blowflies equation with degenerate p-Laplacian diffusion.We prove the existence and nonexistence of non-decreasing smooth tr... We study the existence and stability of monotone traveling wave solutions of Nicholson's blowflies equation with degenerate p-Laplacian diffusion.We prove the existence and nonexistence of non-decreasing smooth traveling wave solutions by phase plane analysis methods.Moreover,we show the existence and regularity of an original solution via a compactness analysis.Finally,we prove the stability and exponential convergence rate of traveling waves by an approximated weighted energy method. 展开更多
关键词 degenerate diffusion P-LAPLACIAN traveling waves stability
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Solving the Generalized Traveling Salesman Problem Using Sequential Constructive Crossover Operator in Genetic Algorithm
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作者 Zakir Hussain Ahmed Maha Ata Al-Furhood +1 位作者 Abdul Khader Jilani Saudagar Shakir Khan 《Computer Systems Science & Engineering》 2024年第5期1113-1131,共19页
The generalized travelling salesman problem(GTSP),a generalization of the well-known travelling salesman problem(TSP),is considered for our study.Since the GTSP is NP-hard and very complex,finding exact solutions is h... The generalized travelling salesman problem(GTSP),a generalization of the well-known travelling salesman problem(TSP),is considered for our study.Since the GTSP is NP-hard and very complex,finding exact solutions is highly expensive,we will develop genetic algorithms(GAs)to obtain heuristic solutions to the problem.In GAs,as the crossover is a very important process,the crossovermethods proposed for the traditional TSP could be adapted for the GTSP.The sequential constructive crossover(SCX)and three other operators are adapted to use in GAs to solve the GTSP.The effectiveness of GA using SCX is verified on some GTSP Library(GTSPLIB)instances first and then compared against GAs using the other crossover methods.The computational results show the success of the GA using SCX for this problem.Our proposed GA using SCX,and swap mutation could find average solutions whose average percentage of excesses fromthe best-known solutions is between 0.00 and 14.07 for our investigated instances. 展开更多
关键词 Generalized travelling salesman problem NP-HARD genetic algorithms sequential constructive crossover swap mutation
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Appropriate Combination of Crossover Operator and Mutation Operator in Genetic Algorithms for the Travelling Salesman Problem
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作者 Zakir Hussain Ahmed Habibollah Haron Abdullah Al-Tameem 《Computers, Materials & Continua》 SCIE EI 2024年第5期2399-2425,共27页
Genetic algorithms(GAs)are very good metaheuristic algorithms that are suitable for solving NP-hard combinatorial optimization problems.AsimpleGAbeginswith a set of solutions represented by a population of chromosomes... Genetic algorithms(GAs)are very good metaheuristic algorithms that are suitable for solving NP-hard combinatorial optimization problems.AsimpleGAbeginswith a set of solutions represented by a population of chromosomes and then uses the idea of survival of the fittest in the selection process to select some fitter chromosomes.It uses a crossover operator to create better offspring chromosomes and thus,converges the population.Also,it uses a mutation operator to explore the unexplored areas by the crossover operator,and thus,diversifies the GA search space.A combination of crossover and mutation operators makes the GA search strong enough to reach the optimal solution.However,appropriate selection and combination of crossover operator and mutation operator can lead to a very good GA for solving an optimization problem.In this present paper,we aim to study the benchmark traveling salesman problem(TSP).We developed several genetic algorithms using seven crossover operators and six mutation operators for the TSP and then compared them to some benchmark TSPLIB instances.The experimental studies show the effectiveness of the combination of a comprehensive sequential constructive crossover operator and insertion mutation operator for the problem.The GA using the comprehensive sequential constructive crossover with insertion mutation could find average solutions whose average percentage of excesses from the best-known solutions are between 0.22 and 14.94 for our experimented problem instances. 展开更多
关键词 travelling salesman problem genetic algorithms crossover operator mutation operator comprehensive sequential constructive crossover insertion mutation
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A Ripple Effect China's simplified travel rules matter for tourism, business and cultural exchange
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作者 Lu Yan 《Beijing Review》 2024年第50期28-29,共2页
China expanded its unilateral visa-free policy to include ordinary passport holders from nine additional countries:Bulgaria,Romania,Croatia,Montenegro,North Macedonia,Malta,Estonia,Latvia and Japan,effective from Nove... China expanded its unilateral visa-free policy to include ordinary passport holders from nine additional countries:Bulgaria,Romania,Croatia,Montenegro,North Macedonia,Malta,Estonia,Latvia and Japan,effective from November 30 to December 31,2025. 展开更多
关键词 travel simplified expanded
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FRESH MOMENTUM AND TRENDS FOR OUTBOUND TRAVEL FROM CHINA--China’s tourism economy is rapidly rebounding, with outbound travel poised to unleash even greater opportunities and stimulate the global tourism industry
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作者 Lu Yan 《China Report ASEAN》 2024年第8期36-37,共2页
In July,Wu Siyan from Nanning,Guangxi Zhuang Autonomous Region,and her husband took their daughter to Thailand.It was the first time the seventh grader had traveled to another country."Traveling in another countr... In July,Wu Siyan from Nanning,Guangxi Zhuang Autonomous Region,and her husband took their daughter to Thailand.It was the first time the seventh grader had traveled to another country."Traveling in another country was an eye-opener for us,especially for my daughter.Some customs in Thailand are similar to those in China's Yunnan Province,but it was still a great opportunity to explore the rest of the world,"Wu said,adding that it only took around two hours to fly from Nanning to Bangkok,capital of Thailand. 展开更多
关键词 travel DAUGHTER Thailand
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Neutral Territory:Cultural Space in Hawthorne’s Travel Writing
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作者 LI Fan PENG Shi-yu 《Cultural and Religious Studies》 2024年第7期428-433,共6页
The emphasis on the combination of physical space and metaphorical space is a major feature of Hawthorne’s narrative.This paper analyzes cultural space in Hawthorne’s travel writing,centering on his works The Old Ma... The emphasis on the combination of physical space and metaphorical space is a major feature of Hawthorne’s narrative.This paper analyzes cultural space in Hawthorne’s travel writing,centering on his works The Old Manse and The Marble Faun from the perspective of neutral territory.The old manse and Rome carry different cultural metaphors,each reflecting a complex and subtle narrative space.Individually,Hawthorne transforms the old manse into Thoreauesque cabin,where American is affected by“sleepiness”and gains spiritual healing.At the national level,Hawthorne creates an allegorical Italy as borderland to explore the existence of American civilization. 展开更多
关键词 Nathaniel Hawthorne neutral philosophy cultural space travel writing
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Analysis of Service Marketing Strategies in the Senior Study Travel Tour Market
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作者 Rui Ye 《Proceedings of Business and Economic Studies》 2024年第3期102-108,共7页
Senior study travel,as an emerging form of tourism,combines the dual characteristics of educational learning and leisure travel.It not only meets the elderly’s desire for spiritual and cultural life and self-fulfillm... Senior study travel,as an emerging form of tourism,combines the dual characteristics of educational learning and leisure travel.It not only meets the elderly’s desire for spiritual and cultural life and self-fulfillment but also promotes the construction of a healthy aging society.This study comprehensively uses methods such as literature analysis,interviews,and case studies to analyze the current status and existing problems of the senior study travel market.Based on the 7Ps service marketing model,it explores service marketing strategies for the senior study travel market,aiming to provide reference and guidance for related tourism enterprises to supply more attractive senior study travel services. 展开更多
关键词 Senior tourism Study travel Service marketing Market strategy
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Bus transit travel time reliability evaluation based on automatic vehicle location data 被引量:4
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作者 严亚丹 过秀成 +2 位作者 李岩 孔哲 何明 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期100-105,共6页
In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed a... In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed and evaluated based on automatic vehicle location (AVL) data. Based on the statistical analysis of the bus transit travel time, six indices including the coefficient of variance, the width of travel time distribution, the mean commercial speed, the congestion frequency, the planning time index and the buffer time index are proposed. Moreover, a framework for evaluating bus transit travel time reliability is constructed. Finally, a case study on a certain bus route in Suzhou is conducted. Results show that the proposed evaluation index system is simple and intuitive, and it can effectively reflect the efficiency and stability of bus operations. And a distinguishing feature of bus transit travel time reliability is the temporal pattern. It varies across different time periods. 展开更多
关键词 bus transit travel time reliability evaluation andanalysis automatic vehicle location data statistical analysis
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从Travel到Tourism——论19世纪英国旅游概念的变易 被引量:5
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作者 张英明 《旅游科学》 CSSCI 2006年第2期1-5,共5页
19世纪初期“tourism”见诸英语,后又取代“travel”的主流地位,标志着英国古典旅行观向现代旅游观的转变。“tourism”概念由于适应了工业文明时代旅游大众化、市场化、产业化的需要,因而从市井俚语上升为20世纪西方旅游理论的主流概... 19世纪初期“tourism”见诸英语,后又取代“travel”的主流地位,标志着英国古典旅行观向现代旅游观的转变。“tourism”概念由于适应了工业文明时代旅游大众化、市场化、产业化的需要,因而从市井俚语上升为20世纪西方旅游理论的主流概念。厘清它与汉语中“旅游”概念之间深刻的文化差异,是中国旅游学界应对西方旅游理论的一大关键。 展开更多
关键词 19世纪 英国 旅游概念 变易行为 消费需求
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THE EQUIVALENT CIRCUIT AND CONTROL SYSTEM OF TRAVELLING WAVE TYPE ULTRASONIC MOTOR
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作者 夏长亮 史婷娜 +1 位作者 薛向党 刘承榆 《Transactions of Tianjin University》 EI CAS 1997年第2期23-27,共5页
The ultrasonic motor is a sort of new type of micromotor with special structure. By use of piezoelectric converse effect of ceramics, the electrical energy is transformed into mechanical energy. Its operating principl... The ultrasonic motor is a sort of new type of micromotor with special structure. By use of piezoelectric converse effect of ceramics, the electrical energy is transformed into mechanical energy. Its operating principle is quite different from that of the traditional motors. In this paper the equivalent circuits of the ring stator and even the whole motor are proposed after studying the equivalent circuit of piezoelectric vibrator. Then the paper makes detailed analyses of each part of the control system, which has been simplified by the equivalent circuit. The theory in this paper has been proved through experiments. 展开更多
关键词 travelling wave type ultrasonic motor equivalent circuit control system
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Speed Control of Travelling Wave Type Ultrasonic Motors Using Artificial Neural Network
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作者 杨忠 金龙 《Journal of Southeast University(English Edition)》 EI CAS 1999年第2期63-68,共6页
Ultrasonic motor (USM) is a newly developed motor, and it has some excellent performances and useful features, therefore, it has been expected to be of practical use. However, the driving principle of USM is different... Ultrasonic motor (USM) is a newly developed motor, and it has some excellent performances and useful features, therefore, it has been expected to be of practical use. However, the driving principle of USM is different from that of other electromagnetic type motors, and the mathematical model is complex to apply to motor control. Furthermore, the speed characteristics of the motor have heavy nonlinearity and vary with driving conditions. Hence, the precise speed control of USM is generally difficult. This paper proposes a new speed control scheme for USM using an artificial neural network. An accurate tracking response can be obtained by random initialization of the weights of the network owing to the powerful on line learning capability. Two prototype ultrasonic motors of travelling wave type were fabricated, both having 100 mm outer diameters of stator and piezoelectric ceramic. The usefulness and validity of the proposed control scheme are examined in experiments. 展开更多
关键词 artificial neural networks ultrasonic motors travelling wave type speed control
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Travel time and alternative configurations analysis for automated storage/retrieval systems based on geometrical method
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作者 马新露 赵林度 Lothar Schulze 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期161-167,共7页
In order to evaluate the efficiency of the automated storage/retrieval system(AS/RS)accurately,and compare different layouts of the AS/RS using mean travel time,under randomized storage conditions,an exact,geometry-ba... In order to evaluate the efficiency of the automated storage/retrieval system(AS/RS)accurately,and compare different layouts of the AS/RS using mean travel time,under randomized storage conditions,an exact,geometry-based analytical model is presented.The model can be used to compute the expected single-command and dual-command travel time for a storage/retrieval(S/R)machine which can travel simultaneously horizontally and vertically as it moves along a storage aisle.The rack may be either square in time or non square in time.Additionally,the alternative layouts of the AS/RS and travel-time models are examined.Comparing with setting the I/O point at the left-lower corner of the rack,setting the I/O point at any point at the vertical edge can help enhance the efficiency of the AS/RS. 展开更多
关键词 travel time model automated storage/retrieval system geometry method Tchebychev approximation
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A Way to Rootedness: Traveling in Tender Is the Night
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作者 王广 《海外英语》 2015年第6期196-197,共2页
Traveling is one major theme of Fitzgerald's novel Tender Is the Night. This fashionable activity for the 1920 s Americans is represented in the novel as ostensibly bearing different meanings to the main character... Traveling is one major theme of Fitzgerald's novel Tender Is the Night. This fashionable activity for the 1920 s Americans is represented in the novel as ostensibly bearing different meanings to the main characters, but a deeper look would reveal that it is unanimously resorted to as a weapon against the spiritual barrenness caused by the cult of business, and more importantly, as a way to the experience of rootedness. 展开更多
关键词 travelING rootedness SPIRITUAL barrenness CULT of business FITZGERALD TENDER Is the NIGHT
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ASYMPTOTIC METHOD OF TRAVELLING WAVE SOLUTIONS FOR A CLASS OF NONLINEAR REACTION DIFFUSION EQUATION 被引量:9
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作者 莫嘉琪 张伟江 何铭 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期777-780,共4页
In this article the travelling wave solution for a class of nonlinear reaction diffusion problems are considered. Using the homotopic method and the theory of travelling wave transform, the approximate solution for th... In this article the travelling wave solution for a class of nonlinear reaction diffusion problems are considered. Using the homotopic method and the theory of travelling wave transform, the approximate solution for the corresponding problem is obtained. 展开更多
关键词 travelling wave solution homotopic method of solution reaction diffusion
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Traveling wave effect on the seismic response of a steel arch bridge subjected to near fault ground motions 被引量:12
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作者 徐艳 George C Lee 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第3期245-257,共13页
In the 1990s, several major earthquakes occurred throughout the world, with a common observation that near fault ground motion (NFGM) characteristics had a distinct impact on causing damage to civil engineering stru... In the 1990s, several major earthquakes occurred throughout the world, with a common observation that near fault ground motion (NFGM) characteristics had a distinct impact on causing damage to civil engineering structures that could not be predicted by using far field ground motions. Since then, seismic responses of structures under NFGMs have been extensively examined, with most of the studies focusing on structures with relatively short fundamental periods, where the traveling wave effect does not need to be considered. However, for long span bridges, especially arch bridges, the traveling wave (only time delay considered) effect may be very distinct and is therefore important. In this paper, the results from a case study on the seismic response of a steel arch bridge under selected NFGMs is presented by considering the traveling wave effect with variable apparent velocities. The effects of fling step and long period pulses of NFGMs on the seismic responses of the arch bridge are also discussed. 展开更多
关键词 traveling wave effect arch bridge near fault ground motion fling step long period pulses
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A Novel Traveling Wave Ultrasonic Motor Using a Bar Shaped Transducer 被引量:4
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作者 金家楣 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第6期961-963,共3页
A novel traveling wave ultrasonic motor was proposed. The structure of the motor is rather simple and different from the conventional traveling wave ultrasonic motors. Its production processes are very convenient. It ... A novel traveling wave ultrasonic motor was proposed. The structure of the motor is rather simple and different from the conventional traveling wave ultrasonic motors. Its production processes are very convenient. It is composed of a stator constituted with a ring and a bar shaped transducer and two cone shaped rotors. The rotors were pressed on inner surface of the ring by means of a pre-pressure system. The bar shaped transducer has a sand- wich-like configuration,where two sets of piezoelectric element are bolted. One set excites a longitudinal vibration of the bar, and the other set excites a flexural vibration of the bar. The ring's traveling wave excited with the longitudinal vibration and the bending vibration of the bar transducer was simulated with FEM (finite element method). The prototype of the motor was made and investigated experimentally for its performance. Its maximum torque and rotating speed are 0.25 N · m and 50 r/min, respectively. 展开更多
关键词 ultrasonic motor traveling wave bar transducer
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The classification of travelling wave solutions and superposition of multi-solutions to Camassa-Holm equation with dispersion 被引量:7
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作者 刘成仕 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期1832-1837,共6页
Under the travelling wave transformation, the Camassa-Holm equation with dispersion is reduced to an integrable ordinary differential equation (ODE), whose general solution can be obtained using the trick of one-par... Under the travelling wave transformation, the Camassa-Holm equation with dispersion is reduced to an integrable ordinary differential equation (ODE), whose general solution can be obtained using the trick of one-parameter group. Furthermore, by using a complete discrimination system for polynomial, the classification of all single travelling wave solutions to the Camassa-Holm equation with dispersion is obtained. In particular, an affine subspace structure in the set of the solutions of the reduced ODE is obtained. More generally, an implicit linear structure in the Camassa-Holm equation with dispersion is found. According to the linear structure, we obtain the superposition of multi-solutions to Camassa-Holm equation with dispersion. 展开更多
关键词 classification of travelling wave solution symmetry group Camassa-Holm equation with dispersion superposition of solutions
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Private Car Travel Characteristics and Influencing Factors in Chinese Cities——A Case Study of Guangzhou in Guangdong,China 被引量:5
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作者 CAO Xiaoshu CHEN Hemei +1 位作者 LI Linna ZHEN Feng 《Chinese Geographical Science》 SCIE CSCD 2009年第4期325-332,共8页
Taking Guangzhou as a case,this paper adopted a questionnaire survey to gather first-hand data and analyzed the characteristics and influencing factors of private car travel in Chinese cities.As the research indicated... Taking Guangzhou as a case,this paper adopted a questionnaire survey to gather first-hand data and analyzed the characteristics and influencing factors of private car travel in Chinese cities.As the research indicated,trip purposes of private car travel are mainly commute and business affairs with a more flexible trip in the urban core area.And trip intensities are concentrated in a certain extent,with trip frequency being lower in the urban core area than the peripheral area.In addition,the trip time has two significant peaks occurring in the morning and afternoon,and one trough in the midday.And trip spatial distribution is mainly within commute with both residence and employment in urban area and inward commute with residence in suburban area while employment in urban area.Both kinds of commutes direct to the urban area.The study also shows that the characteristics of private car travel are principally influenced by two aspects:travelers' attributes and urban characteristics.The main travelers' social and economic attributes influenced it include the gender,education attainment,age,driving experience and per capita monthly household income.The urban characteristics influenced it mainly cover the land use pattern,public traffic facilities and spatial attributes of residential environment. 展开更多
关键词 car travel travel characteristics private car Chinese cities GUANGZHOU
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Alpha-reliable combined mean traffic equilibrium model with stochastic travel times 被引量:5
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作者 张文义 关伟 +1 位作者 宋丽英 孙会君 《Journal of Central South University》 SCIE EI CAS 2013年第12期3770-3778,共9页
Based on the reliability budget and percentile travel time(PTT) concept, a new travel time index named combined mean travel time(CMTT) under stochastic traffic network was proposed. CMTT here was defined as the convex... Based on the reliability budget and percentile travel time(PTT) concept, a new travel time index named combined mean travel time(CMTT) under stochastic traffic network was proposed. CMTT here was defined as the convex combination of the conditional expectations of PTT-below and PTT-excess travel times. The former was designed as a risk-optimistic travel time index, and the latter was a risk-pessimistic one. Hence, CMTT was able to describe various routing risk-attitudes. The central idea of CMTT was comprehensively illustrated and the difference among the existing travel time indices was analyzed. The Wardropian combined mean traffic equilibrium(CMTE) model was formulated as a variational inequality and solved via an alternating direction algorithm nesting extra-gradient projection process. Some mathematical properties of CMTT and CMTE model were rigorously proved. Finally, a numerical example was performed to characterize the CMTE network. It is founded that that risk-pessimism is of more benefit to a modest(or low) congestion and risk network, however, it changes to be risk-optimism for a high congestion and risk network. 展开更多
关键词 travel behavior risk attitude travel time reliability combined mean travel time wardropian user equilibrium
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Mode of travel and the decision to allow children to walk or bike to schools—The Abu Dhabi experience 被引量:2
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作者 Masood A. Badri Abdulla M. Ustadi +1 位作者 Lynne Pierson Mubarak Al Dramaki 《Open Journal of Preventive Medicine》 2012年第4期514-527,共14页
The study investigates school travel to and from schools as perceived by parents in Abu Dhabi, United Arab Emirates. Far fewer children are cycling or walking to school, and more and more are being driven to school by... The study investigates school travel to and from schools as perceived by parents in Abu Dhabi, United Arab Emirates. Far fewer children are cycling or walking to school, and more and more are being driven to school by car. Traffic conditions, environmental factors, distance to school, road’s infrastructures, walking or biking with groups, schools efforts to educate children about active travel, and preferences of parents to accompany children to school were significantly perceived as important. The absence of active travel culture in the community was seen as a significant factor. Parent’s gender, child’s gender, child’s grade level, number of cars owned by the family, nationality and number of children were significantly associated with parents’ decisions to allow active travel to school. Results show that Abu Dhabi must establish aggressive strategic plans to promote active-commuting to school as the main mode of transportation. Current conditions in Abu Dhabi City are not conducive to active travel to school. 展开更多
关键词 MODE of travel ACTIVE travel to SCHOOL Factors Affecting ACTIVE travel Walking to SCHOOL Biking to SCHOOL Abu Dhabi
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