一个滑雪短视频带来的爆款新闻——《山东四岁萌娃的“滑雪日记”》创作谈

随着媒体深度融合的推进,电视新闻的选题渠道、创作方式、产品内容等都发生了改变。本文以《山东四岁萌娃的“滑雪日记”》为主要分析文本,分析创作经验。从一个短视频激发出灵感,到用短视频思维创新编辑打造“滑雪日记”,表明了只有正能量才能带来大流量。

Pacing and predictors of performance during cross-country skiing races:A systematic review

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/）.

Limb symmetry index in competitive alpine ski racers:Reference values and injury risk identification according to age-related performance levels

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/）.

A comparison of lower limb stiffness and mechanical muscle function in ACL-reconstructed,elite,and adolescent alpine ski racers/ski cross athletes

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/）.

DARPA Robotics Grand Challenge Participation and Ski-Type Gait for Rough-Terrain Walking

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.

Alterations of the Nitrogen Mineralization Rates in Soils of Forest Community Depending on the Ski Run Construction (Mount Uludag,Bursa,Turkey)

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.

The effect of sex and performance level on pacing in cross-country skiers:Vasaloppet 2004-2017

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/）.

Progress in Research on the Impacts of Global Climate Change on Winter Ski Tourism

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.

Experimental Investigation of the Aerodynamic Flow in the Aircraft Carrier Ski-jump by means of PIV

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.

滑雪

图中是整装待发的滑雪健儿．只要你从左上方入口走到有下方出口，便会发现这个迷宫的神奇了。

Flow Experience Study of Eco-tourists: A Case Study of Hunan Daweishan Mountain Ski Area

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.

The Spatio-temporal Evolution of Ski Resorts in the Beijing-Tianjin-Hebei Region:Characteristics and Influencing Factors

Ski resorts are one of the bases for the development of ice-snow sports and tourism,and they are also a hot topic of social concern.Taking 117 ski resorts in Beijing,Tianjin and Hebei as the research object,geospatial analysis methods such as kernel density and spatial autocorrelation were used to explore the spatial and temporal distribution patterns of the ski resorts.The geographic detector was used to deeply explore the underlying factors influencing the spatial and temporal distribution of ski resorts in terms of policy factors,natural factors and economic and social factors.This study found that the spatial and temporal distribution of ski resorts in the Beijing-Tianjin-Hebei Region showed a significant Olympic event-driven characteristic.From 2009 to 2021,the spatial pattern of Beijing-Tianjin-Hebei ski resorts has changed from“single-core development”,to a“single-core with multi-point”layout,and then to a“multi-core”layout.The spatial pattern has changed from agglomeration to diffusion.Cold and hot spots of the spatial and temporal characteristics in Beijing-Tianjin-Hebei ski resort have shifted from north to south,from the initial suburbs of Beijing to the southern cities of Baoding,Shijiazhuang,Xingtai and other cities in Hebei Province.The spatial and temporal distribution of Beijing-Tianjin-Hebei ski resorts has been influenced by many factors,from“GDP per capita”to“population density”to“policy quantity”,showing a shift from“Economic-driven”to“population-driven”to“policy-driven”processes.

Does Ski Tourism Improve the Regional Economy?The Case Study of Chongli,China

Chongli is one of the venues for the Beijing 2022 Winter Olympics.Since 2009,the government of Chongli has emphasized the development of a tourism strategy,which gradually contributed to alleviating regional poverty.With data collected from 2009 to 2019,ski tourism and the regional economy in Chongli were analyzed using the Coupling Coordination Degree(CCD)Model.This analysis indicated,first,there were three stages in the relationship between ski tourism and the regional economy in Chongli,including weak coordination(2009–2011),starting coordination(2012–2015),and strong coordination(2016–2019).Second,sport tourism,such as ski tourism,is likely to contribute to the regional economy and alleviate poverty.Third,the case of Chongli illustrates that policy and sports events are significant for helping a place to develop sports tourism,in addition to making full use of local resources.Finally,the development of skiing tourism has had a positive impact on citizens’and farmers’incomes,though it may have impacted citizens more.This research suggests that regional resources are essential for the development of sport tourism and the promotion of regional economies.Developing regions should seize the bonus period of sports events and policies.More attention should be paid to the differences between urban citizens and farmers in order to establish a better redistribution system.Considering the climatic factors,more studies need to analyze the sustainability of ski tourism in developing regions.

Exploring the Tourism Experience of Beginner Skiers in the Emerging Ski Market

The skiing economy is a typical experience economy,so understanding the experience of ski tourists is essential to the development of the destination.To enrich the tourism experience research in the emerging ski market,this paper studies the 7118 online reviews of beginner skiers by selecting the main ski resorts in China as a case study.The content analysis method and sentiment analysis based on the domain lexicon and custom rules are combined to explore the perception characteristics of the beginners from the two aspects of experience dimension and experience satisfaction.Three main results were found.(1)The five main dimensions that affect the ski tourism experience of beginners are interaction perception,price perception,reputation perception,risk perception and functional perception.(2)For beginners,skiing is the primary purpose of tourism instead of being the critical factor of the positive reviews.They pay more attention to the pleasure produced by interpersonal interactions.(3)From 2014/2015 ski season to 2010/2021 ski season,the positive sentiment of beginners had no obvious change,while the negative sentiment showed a continuous downward trend,and the negative sentiment was mainly distributed among reviews on price,low temperature and service.This paper not only expands the research perspective of ski tourism,but also provides managerial inspiration for ski destinations interested in attracting beginners from the emerging ski markets.

The Moderating Effect of the Ski Resort Environment on the Skier’s Travel Radius under the Restriction of Skill Consumption

Starting from the skill characteristics of ski tourism,this paper discusses the impact of consumer skill on travel decisions,and the moderating effect of the ski resort’s comprehensive leisure environment(including the ski resort sports environment and the regional cultural tourism environment),in order to both understand their impacts on the travel distance characteristics of skiers and attempt to provide necessary research support for the development of China’s ski industry and the construction of destinations.Based on the data from multi-period visitor surveys,this paper constructs the consumption skill-travel radius decision-making influence model under the moderating effect of the ski resort comprehensive leisure environment.The results show three main characteristics.(1)The travel radius obviously differs among skiers with different skill levels.The skill level of skiers has a significant positive effect on the larger travel radius,and a significant negative effect on the smaller travel radius.That is,skiers with a higher skill level are more inclined to undertake long-distance skiing travel,while skiers with a lower skill level are more inclined to undertake short-distance skiing travel.(2)The comprehensive leisure environment has a significant moderating effect on the skiers’travel radius,with a significant positive impact on enlarging the travel radius,while the influences on high-skill and low-skill skiers are significantly higher than on middle-skill skiers.(3)In the comprehensive leisure environment,there are differences in the moderating effect of the ski resort sports environment and the regional cultural tourism environment on the skiers travel radius,and the positive moderating effect of the ski resort sports environment on the high-skill skiers’travel radius is more obvious.While the regional cultural tourism environment has a more obvious positive moderating effect on the travel radius of non-skiers and junior skiers,it is more conducive to promoting domestic travel.In general,the skier skill level in China was generally lower,and the ski resort comprehensive leisure environment optimization is conducive to overcoming the limitation of the travel radius caused by the disadvantageous skill level of consumers.However,to promote the development of China’s ski industry in the long run,it is necessary to focus on improving the consumer’s ski skill level,but prevent the risk of losing high-skill consumers overseas.In the course of improving the level of domestic ski sports facilities,we should also focus on the domestic leisure cultural tourism environment to better enhance the attractiveness of domestic ski destinations.

Resilience:Analyzing the Crisis Management of Ski Resorts in China

Resilience has become an important concept for the ski resorts of China,which have suffered heavy losses due to COVID-19.In order to help China’s ski resort service industry successfully adapt to the crisis and achieve sustainable development,the goal of this paper is to develop the definition of resilience of the ski resort service industry through interviews based on the concept and general analysis framework of resilience.The ski resort resilience theory analysis framework is then constructed from the three basic elements(market,skiing,and stakeholders)and four system features(flexibility,adaptability,and collaborative learning ability).The results indicate several measures that can be taken to spread risk:enrich the product supply;eliminate risks and build a multi-agent networked industrial governance system;and establish a risk prevention and management mechanism based on a multi-organization alternative learning mechanism to overcome the difficulties encountered in the development of ski resorts.