Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on t...Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on this sport, no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance. The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers. Methods： Four electronic databases were searched using relevant subject headings and keywords. Only original research articles published in peerreviewed journals and the English language and addressing performance, biomechanics, physiology, and anthropometry of XCS racers were reviewed. Results： All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies. None of the articles involved the use of an experimental design. Furthermore, potential changes in external conditions （e.g.,weather, ski properties） were not taken into consideration. A comparable number of studies focused on the skating or classical technique. In most cases, positive pacing was observed, with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy. The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies, which was not the case for cycle rate. In general, uphill performance was closely related to overall race performance, with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers. Moreover, pacing was coupled to the selection and distribution of technique during a race, with faster skiers employing more double poling and kick double poling, less diagonal stride, and more V2 （double dance） than V1 （single dance） skating across a race. Conclusion： We propose that skiers at all levels can improve their performance with more specific training in techniques （i.e., maintaining long cycles without compromising cycle rate and selecting appropriate techniques） in combination with training for endurance and more strength. Furthermore, we would advise less experienced skiers and/or those with lower levels of performance to apply a more even pacing strategy rather than a positive one （i.e., starting the race too fast）.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.展开更多
Purpose： The aims of this study were to assess differences of limb symmetry index （LSI） in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related pe...Purpose： The aims of this study were to assess differences of limb symmetry index （LSI） in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related performance levels and to prospectively assess limb differences as a possible risk factor for traumatic and overuse injury in youth ski racers. Methods： The study （Study 1） included 285 high-level competitive ski racers （125 females, 160 males） of 3 age-related performance levels and based on the school system： 95 youth （10-14 years, secondary modem school）, 107 adolescent （15-19 years, grammar school）, and 83 elite athletes （20-34 years）. To investigate the second aim （Study 2）, 67 of the 95 youth athletes were included and any traumatic or overuse injuries were prospectively recorded over 2 seasons. All athletes performed 4 unilateral tests （strength related： one-leg counter movement jump （OL-CMJ） and one-leg isometric/isokinetic press strength test （OL-ILS）; coordination related： one-leg stability test （OL-ST） and one-leg speedy jump test （OL-SJ））. The LSI was calculated by dividing the dominant leg by the nondominant leg and multiplying by 100. Kruskal-Wallis H tests and binary logistic regression analyses were conducted. Results： There were significant differences between the LSI of the 3 age-related performance-level groups only in the strength-related tests： the OL-CMJ （X^2（2, 285） = 9.09; p = 0.01） and the OL-ILS （X^2（2,285） = 14.79; p 〈 0.01）. The LSI for OL-ILS was found to be a significant risk factor for traumatic injury in youth ski racers （Wald = 7.08; p 〈 0.01）. No significant risk factors were found for overuse injuries. Conclusion： Younger athletes display slightly greater LSI values only in the strength-related tests. The cut-off value of limb differences of 〈 10% for return to sport decisions seems to be appropriate for elite athletes, but for youth and adolescent athletes it has to be critically discussed. It seems to be necessary to define thresholds based on specific performance tasks （strength vs. coordination related） rather than on generalizations, and age-related performance levels must be considered. Limb differences in unilateral leg extension strength represent a significant injury risk factor in youth ski racers.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.展开更多
Purpose： The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed （ACLR）, elite （ELITE）, and ado...Purpose： The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed （ACLR）, elite （ELITE）, and adolescent （ADOL） alpine ski racers and ski cross athletes. Methods： Alpine ski racers/ski crossers （ACLR： n = 12, age = 26.7 ± 3.8 years; ELITE： n = 12, age = 23.9 ± 3.0 years; ADOL： n = 12, age = 17.8 ± 0.7 years; females： n = 6 per group, males： n = 6 per group） performed 5 maximal countermovement jumps （CMJs） and 5 squat jumps. The ground reaction forces for each limb were analyzed using dual force plate recording to obtain body center of mass （BCM） velocity, displacement, and power. The eccentric deceleration （ECC） and concentric phases were determined from BCM velocity. CMJ net concentric and ECC impulses were calculated （body mass normalized） along with the peak and mean BCM power and maximal vertical jump height. CMJ lower limb stiffness （LLS） was determined by the slope of the ground reaction forces vs. the BCM displacement curve over the ECC phase. Concentric and ECC asymmetry indices were calculated for each leg, and the left vs. right LLS was compared. Outcome measures （reported as mean ± SD） calculated as a 5-jump mean were normalized to body mass and compared using an analysis of variance. Results： No between-group differences were found for peak and mean power or jump heights. There were no group differences for LLS or net concentric phase impulse, but the net ECC impulse was lower in the ADOL group compared with ELITE skiers （ADOL： 1.33 ± 0.32 Ns/kg; ELITE： 1.59 ± 0.16 Ns/kg; p 〈 0.05）. Although no group differences were found for ECC asymmetry indices, a group × limb interaction was found for LLS （p 〈 0.01）, which was systematically higher in the right vs. the left limb of ADOL skiers （right： 54.1 ± 17.9 N/m/kg; left： 48.7 ± 15.7 N/m/kg;p 〈 0.01）. Conclusion： ADOL skiers demonstrated decreased ECC impulse and systematic right limb dominance in LLS compared with ACLR and ELITE skiers. The implication of these findings for injury and performance are unknown, but further investigation into these potential relationships is warranted.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.展开更多
In this paper, we briefly introduce the history of the Defense Advanced Research Projects Agency(DARPA) Grand Challenge programs with particular focus on the 2012 Robotics Challenge. As members of team DRC-HUBO, we pr...In this paper, we briefly introduce the history of the Defense Advanced Research Projects Agency(DARPA) Grand Challenge programs with particular focus on the 2012 Robotics Challenge. As members of team DRC-HUBO, we propose different approaches for the Rough-Terrain task, such as enlarged foot pedals and a transformation into quadruped walking. We also introduce a new gait for humanoid robot locomotion to improve stability performance, called the Ski-Type gait. We analyze the stability performance of this gait and use the stability margin to choose between two candidate step sequences, Crawl-1 and Crawl-2. Next, we perform a force/torque analysis for the redundant closedchain system in the Ski-Type gait, and determine the joint torques by minimizing the total energy consumption. Based on the stability and force/torque analysis, we design a cane length to support a feasible and stable Crawl-2 gait on the HUBO2 humanoid robot platform. Finally, we compare our experimental results with biped walking to validate the SkiType gait. We also present our team performance in the trials of the Robotics Challenge.展开更多
Since 194os, Mount Uludag （Bithynian Olympus） has been considered famous with winter sports center in Turkey. In addition, it is one of the rare places because of its plant diversity and is also one of the important...Since 194os, Mount Uludag （Bithynian Olympus） has been considered famous with winter sports center in Turkey. In addition, it is one of the rare places because of its plant diversity and is also one of the important plant areas of Turkey. The ski run constructions are rapidly increased in the past decades in the alpine and subalpine belts of the mountain. Rate of nitrogen mineralization and some properties of soft were investigated in the soils of the three ski runs and undisturbed neighborhood forest sites. These ski runs are at the upper part of the forest belt in the mountain. Abies bornmuelleriana forest community is the postclimax and very sensitive to destruetion. The rates of the nitrogen mineralization in the soils were determined in controlled conditions （60% water-holding capacity, 20℃）. Nitrification and nitrogen mineralization were in the ski run inside where the natural recovery started, increased compared with the outside of the ski runs. Waterholding capacity, organic carbon, and total nitrogen were decreased in the massive damaged ski run, and due to these changes, the rates of mineralization and nitrification were also decreased.展开更多
Background： Pacing, defined as percentage changes of speed between successive splits, has been extensively studied in running and cycling endurance sports; however, less information about the trends in change of spee...Background： Pacing, defined as percentage changes of speed between successive splits, has been extensively studied in running and cycling endurance sports; however, less information about the trends in change of speed during cross-country （XC） ski racing is available. Therefore, the aim of the present study was to examine the effect of performance （quartiles of race time （Q）, with Q1 the fastest and Q4 the slowest） level on pacing in the Vasaloppet ski race, the largest XC skiing race in the world. Methods： For this purpose, we analyzed female （n = 19,465） and male （n = 164,454） finishers in the Vasaloppet ski race from 2004 to 2017 using a one-way （2 sexes） analysis of variance with repeated measures to examine percentage changes of speed between 2 successive splits. Overall, the race consisted of 8 splits. Results： The race speeds of Q1, Q2, Q3, and Q4 were 13.6 ± 1.8, 10.6 ± 0.5, 9.2 ± 0.3, and 8.1 ±- 0.4 km/h, respectively, among females and 16.7 ± 1.7, 13.1 ± 0.7, 10.9 ± 0.6, and 8.9 ± 0.7 km/h, respectively, among males. The overall pacing strategy of finishers was variable. A small sex × split interaction on speed was observed （η^2= 0.016, p 〈 0.001）, with speed difference between sexes ranging from 14.9% （Split 7） to 27.0% （Split 1） and larger changes in speed between 2 successive splits being shown for females （p 〈 0.001, η^2=0.004）. A large performance × split interaction on speed, with Q1 presenting the smallest changes of speed between splits, was shown for females （η^2= 0.149, p 〈 0.001） and males （η^2 = 0.169,p 〈 0.001）. Conclusion： Male and fast XC skiers are more even pacers. Coaches and athletes should develop tailored sex- and performance-level pacing strategies; for instance, they should advise fast XC skiers to start fast and maintain their speed, rather than starting slowly and trying to make up time by going faster at times during the race.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.展开更多
The impacts of global climate change on ski tourism, which depends heavily on climate conditions, have increasingly gained concern overseas. This paper systematically summarized the relevant research ideas, the techni...The impacts of global climate change on ski tourism, which depends heavily on climate conditions, have increasingly gained concern overseas. This paper systematically summarized the relevant research ideas, the technical methods used, and the obtained achievements through an extensive synthesis of the previous studies. Moreover, the major shortcomings and the limitations in the recent studies are pointed in order to present a useful reference for our Chinese investigators. It indicates that the future climate warming would cause the loss of skiable areas, the shortening of skiing seasons and the sharp drop of ski visitors in many low altitude and low latitude ski resorts. The paper finally stressed that future research should pay particular attention to strengthening interdisciplinary cooperation and consider more factors about the impacts of climate-induced environmental changes on tourist flows. In the future ski resort planning and management, the possible impacts of global climate change should be taken into account.展开更多
Computational Fluid Dynamics （CFD） methods have opened a new field to perform aerodynamic studies saving money and time. The difficulties presented by this method to calculate complex flow field problems imply that ...Computational Fluid Dynamics （CFD） methods have opened a new field to perform aerodynamic studies saving money and time. The difficulties presented by this method to calculate complex flow field problems imply that CFD validation is needed to provide correct results. Experimental data have recently been used to validate the accuracy of CFD predictions. Particle Image Velocimetry （PIV） has shown to be a powerful tool in the investigation of complex flows. The aim of this paper is to present results from PIV experiments that would be interesting for CFD validation. Regarding aircraft operations, the short runway available implies the necessity of equipment which helps to take-off performances. Ski-jump ramp system improves aircraft performances by an increment of lift resulting in successful take-off operations. The ski-jump ramp presence generates a complex flow bounded by a turbulent shear layer and a low velocity recirculation bubble over the end of the flight deck. The adverse effects on the aircraft aerodynamics affect to pilot safe operations, so this region is an interesting problem to be studied by means of wind tunnel experimental tests.展开更多
Mountain skiing has become a popular winter ecotourism activity in China. Studying the loyalty of eco-tourists from the perspective of tourist experience is important to the continued development of mountain ski touri...Mountain skiing has become a popular winter ecotourism activity in China. Studying the loyalty of eco-tourists from the perspective of tourist experience is important to the continued development of mountain ski tourism. Based on the flow experience theory, we developed and tested a structural equation model to examine relationships among flow experience, positive emotions and the loyalty of eco-tourists. Survey data from 324 eco-tourists with skiing experience at Daweishan Mountain Ski Resort was used for exploratory factor, confirmatory factor and path analyses. Results revealed five dimensions of flow experiences of eco-tourists： Concentration on task at hand, Loss of self-consciousness, Transformation of time, Autotelic experience, and Challenge-skill balance. As hypothesized, influences of Transformation of time, Autotelic experience and Challenge-skill balance on positive emotions were significant and positive. Concentration on task at hand, Autotelic experience, Challenge-skill balance and positive emotions positively influenced the loyalty of eco-tourists. Suggestions for developing ecotourism products are discussed such as designing a conductive environment to activate flow experience, providing personalized service to promote positive emotion, and developing experiential tourism activities.展开更多
文摘Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on this sport, no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance. The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers. Methods： Four electronic databases were searched using relevant subject headings and keywords. Only original research articles published in peerreviewed journals and the English language and addressing performance, biomechanics, physiology, and anthropometry of XCS racers were reviewed. Results： All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies. None of the articles involved the use of an experimental design. Furthermore, potential changes in external conditions （e.g.,weather, ski properties） were not taken into consideration. A comparable number of studies focused on the skating or classical technique. In most cases, positive pacing was observed, with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy. The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies, which was not the case for cycle rate. In general, uphill performance was closely related to overall race performance, with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers. Moreover, pacing was coupled to the selection and distribution of technique during a race, with faster skiers employing more double poling and kick double poling, less diagonal stride, and more V2 （double dance） than V1 （single dance） skating across a race. Conclusion： We propose that skiers at all levels can improve their performance with more specific training in techniques （i.e., maintaining long cycles without compromising cycle rate and selecting appropriate techniques） in combination with training for endurance and more strength. Furthermore, we would advise less experienced skiers and/or those with lower levels of performance to apply a more even pacing strategy rather than a positive one （i.e., starting the race too fast）.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.
文摘Purpose： The aims of this study were to assess differences of limb symmetry index （LSI） in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related performance levels and to prospectively assess limb differences as a possible risk factor for traumatic and overuse injury in youth ski racers. Methods： The study （Study 1） included 285 high-level competitive ski racers （125 females, 160 males） of 3 age-related performance levels and based on the school system： 95 youth （10-14 years, secondary modem school）, 107 adolescent （15-19 years, grammar school）, and 83 elite athletes （20-34 years）. To investigate the second aim （Study 2）, 67 of the 95 youth athletes were included and any traumatic or overuse injuries were prospectively recorded over 2 seasons. All athletes performed 4 unilateral tests （strength related： one-leg counter movement jump （OL-CMJ） and one-leg isometric/isokinetic press strength test （OL-ILS）; coordination related： one-leg stability test （OL-ST） and one-leg speedy jump test （OL-SJ））. The LSI was calculated by dividing the dominant leg by the nondominant leg and multiplying by 100. Kruskal-Wallis H tests and binary logistic regression analyses were conducted. Results： There were significant differences between the LSI of the 3 age-related performance-level groups only in the strength-related tests： the OL-CMJ （X^2（2, 285） = 9.09; p = 0.01） and the OL-ILS （X^2（2,285） = 14.79; p 〈 0.01）. The LSI for OL-ILS was found to be a significant risk factor for traumatic injury in youth ski racers （Wald = 7.08; p 〈 0.01）. No significant risk factors were found for overuse injuries. Conclusion： Younger athletes display slightly greater LSI values only in the strength-related tests. The cut-off value of limb differences of 〈 10% for return to sport decisions seems to be appropriate for elite athletes, but for youth and adolescent athletes it has to be critically discussed. It seems to be necessary to define thresholds based on specific performance tasks （strength vs. coordination related） rather than on generalizations, and age-related performance levels must be considered. Limb differences in unilateral leg extension strength represent a significant injury risk factor in youth ski racers.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.
基金the Killam Foundation provided funding for this research
文摘Purpose： The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed （ACLR）, elite （ELITE）, and adolescent （ADOL） alpine ski racers and ski cross athletes. Methods： Alpine ski racers/ski crossers （ACLR： n = 12, age = 26.7 ± 3.8 years; ELITE： n = 12, age = 23.9 ± 3.0 years; ADOL： n = 12, age = 17.8 ± 0.7 years; females： n = 6 per group, males： n = 6 per group） performed 5 maximal countermovement jumps （CMJs） and 5 squat jumps. The ground reaction forces for each limb were analyzed using dual force plate recording to obtain body center of mass （BCM） velocity, displacement, and power. The eccentric deceleration （ECC） and concentric phases were determined from BCM velocity. CMJ net concentric and ECC impulses were calculated （body mass normalized） along with the peak and mean BCM power and maximal vertical jump height. CMJ lower limb stiffness （LLS） was determined by the slope of the ground reaction forces vs. the BCM displacement curve over the ECC phase. Concentric and ECC asymmetry indices were calculated for each leg, and the left vs. right LLS was compared. Outcome measures （reported as mean ± SD） calculated as a 5-jump mean were normalized to body mass and compared using an analysis of variance. Results： No between-group differences were found for peak and mean power or jump heights. There were no group differences for LLS or net concentric phase impulse, but the net ECC impulse was lower in the ADOL group compared with ELITE skiers （ADOL： 1.33 ± 0.32 Ns/kg; ELITE： 1.59 ± 0.16 Ns/kg; p 〈 0.05）. Although no group differences were found for ECC asymmetry indices, a group × limb interaction was found for LLS （p 〈 0.01）, which was systematically higher in the right vs. the left limb of ADOL skiers （right： 54.1 ± 17.9 N/m/kg; left： 48.7 ± 15.7 N/m/kg;p 〈 0.01）. Conclusion： ADOL skiers demonstrated decreased ECC impulse and systematic right limb dominance in LLS compared with ACLR and ELITE skiers. The implication of these findings for injury and performance are unknown, but further investigation into these potential relationships is warranted.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.
文摘In this paper, we briefly introduce the history of the Defense Advanced Research Projects Agency(DARPA) Grand Challenge programs with particular focus on the 2012 Robotics Challenge. As members of team DRC-HUBO, we propose different approaches for the Rough-Terrain task, such as enlarged foot pedals and a transformation into quadruped walking. We also introduce a new gait for humanoid robot locomotion to improve stability performance, called the Ski-Type gait. We analyze the stability performance of this gait and use the stability margin to choose between two candidate step sequences, Crawl-1 and Crawl-2. Next, we perform a force/torque analysis for the redundant closedchain system in the Ski-Type gait, and determine the joint torques by minimizing the total energy consumption. Based on the stability and force/torque analysis, we design a cane length to support a feasible and stable Crawl-2 gait on the HUBO2 humanoid robot platform. Finally, we compare our experimental results with biped walking to validate the SkiType gait. We also present our team performance in the trials of the Robotics Challenge.
基金supported by the United Nations Development,Global Environment Facility,Small Grants Programme
文摘Since 194os, Mount Uludag （Bithynian Olympus） has been considered famous with winter sports center in Turkey. In addition, it is one of the rare places because of its plant diversity and is also one of the important plant areas of Turkey. The ski run constructions are rapidly increased in the past decades in the alpine and subalpine belts of the mountain. Rate of nitrogen mineralization and some properties of soft were investigated in the soils of the three ski runs and undisturbed neighborhood forest sites. These ski runs are at the upper part of the forest belt in the mountain. Abies bornmuelleriana forest community is the postclimax and very sensitive to destruetion. The rates of the nitrogen mineralization in the soils were determined in controlled conditions （60% water-holding capacity, 20℃）. Nitrification and nitrogen mineralization were in the ski run inside where the natural recovery started, increased compared with the outside of the ski runs. Waterholding capacity, organic carbon, and total nitrogen were decreased in the massive damaged ski run, and due to these changes, the rates of mineralization and nitrification were also decreased.
文摘Background： Pacing, defined as percentage changes of speed between successive splits, has been extensively studied in running and cycling endurance sports; however, less information about the trends in change of speed during cross-country （XC） ski racing is available. Therefore, the aim of the present study was to examine the effect of performance （quartiles of race time （Q）, with Q1 the fastest and Q4 the slowest） level on pacing in the Vasaloppet ski race, the largest XC skiing race in the world. Methods： For this purpose, we analyzed female （n = 19,465） and male （n = 164,454） finishers in the Vasaloppet ski race from 2004 to 2017 using a one-way （2 sexes） analysis of variance with repeated measures to examine percentage changes of speed between 2 successive splits. Overall, the race consisted of 8 splits. Results： The race speeds of Q1, Q2, Q3, and Q4 were 13.6 ± 1.8, 10.6 ± 0.5, 9.2 ± 0.3, and 8.1 ±- 0.4 km/h, respectively, among females and 16.7 ± 1.7, 13.1 ± 0.7, 10.9 ± 0.6, and 8.9 ± 0.7 km/h, respectively, among males. The overall pacing strategy of finishers was variable. A small sex × split interaction on speed was observed （η^2= 0.016, p 〈 0.001）, with speed difference between sexes ranging from 14.9% （Split 7） to 27.0% （Split 1） and larger changes in speed between 2 successive splits being shown for females （p 〈 0.001, η^2=0.004）. A large performance × split interaction on speed, with Q1 presenting the smallest changes of speed between splits, was shown for females （η^2= 0.149, p 〈 0.001） and males （η^2 = 0.169,p 〈 0.001）. Conclusion： Male and fast XC skiers are more even pacers. Coaches and athletes should develop tailored sex- and performance-level pacing strategies; for instance, they should advise fast XC skiers to start fast and maintain their speed, rather than starting slowly and trying to make up time by going faster at times during the race.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.
基金the foundation for the Project of Key Subject of Human Geography of Fujian Normal University for the partial financial support of this research
文摘The impacts of global climate change on ski tourism, which depends heavily on climate conditions, have increasingly gained concern overseas. This paper systematically summarized the relevant research ideas, the technical methods used, and the obtained achievements through an extensive synthesis of the previous studies. Moreover, the major shortcomings and the limitations in the recent studies are pointed in order to present a useful reference for our Chinese investigators. It indicates that the future climate warming would cause the loss of skiable areas, the shortening of skiing seasons and the sharp drop of ski visitors in many low altitude and low latitude ski resorts. The paper finally stressed that future research should pay particular attention to strengthening interdisciplinary cooperation and consider more factors about the impacts of climate-induced environmental changes on tourist flows. In the future ski resort planning and management, the possible impacts of global climate change should be taken into account.
文摘Computational Fluid Dynamics （CFD） methods have opened a new field to perform aerodynamic studies saving money and time. The difficulties presented by this method to calculate complex flow field problems imply that CFD validation is needed to provide correct results. Experimental data have recently been used to validate the accuracy of CFD predictions. Particle Image Velocimetry （PIV） has shown to be a powerful tool in the investigation of complex flows. The aim of this paper is to present results from PIV experiments that would be interesting for CFD validation. Regarding aircraft operations, the short runway available implies the necessity of equipment which helps to take-off performances. Ski-jump ramp system improves aircraft performances by an increment of lift resulting in successful take-off operations. The ski-jump ramp presence generates a complex flow bounded by a turbulent shear layer and a low velocity recirculation bubble over the end of the flight deck. The adverse effects on the aircraft aerodynamics affect to pilot safe operations, so this region is an interesting problem to be studied by means of wind tunnel experimental tests.
基金Humanities and Social Science Foundation of Hunan Province(16JD48)
文摘Mountain skiing has become a popular winter ecotourism activity in China. Studying the loyalty of eco-tourists from the perspective of tourist experience is important to the continued development of mountain ski tourism. Based on the flow experience theory, we developed and tested a structural equation model to examine relationships among flow experience, positive emotions and the loyalty of eco-tourists. Survey data from 324 eco-tourists with skiing experience at Daweishan Mountain Ski Resort was used for exploratory factor, confirmatory factor and path analyses. Results revealed five dimensions of flow experiences of eco-tourists： Concentration on task at hand, Loss of self-consciousness, Transformation of time, Autotelic experience, and Challenge-skill balance. As hypothesized, influences of Transformation of time, Autotelic experience and Challenge-skill balance on positive emotions were significant and positive. Concentration on task at hand, Autotelic experience, Challenge-skill balance and positive emotions positively influenced the loyalty of eco-tourists. Suggestions for developing ecotourism products are discussed such as designing a conductive environment to activate flow experience, providing personalized service to promote positive emotion, and developing experiential tourism activities.
