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Quantifying spatial scale of positive and negative terrains pattern at watershed-scale:Case in soil and water conservation region on Loess Plateau

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Journal of Mountain Science 2017年第8期14卷 1642-1654页

作者： YANG Feng ZHOU Yi school of Geography and tourism Shaanxi Normal University

The positive and negative terrains(P-N terrains) widely distributed across China's Loess Plateau constitute the dual structure characteristic of loess landforms. Analysis of loess P-N terrains at the watershed scale can serve to elucidate the structural characteristics and spatial patterns of P-N terrains, which benefits a better understanding of watershed evolution and suitable scales for loess landform research. The Two-Term Local Quadrat Variance Analysis(TTLQV) is calculated as the average of the square of the difference between the block totals of all possible adjacent pairs of block size, which can be used to detect both the scale and the intensity of landscape patches(e.g., plant/animal communities and gully networks). In this study, we determined the latitudinal and longitudinal spatial scale of P-N terrain patterns within 104 uniformly distributed watersheds in our target soil and water conservation region. The results showed that TTLQV is very effective for examining the scale of P-N terrain patterns. There were apparently three types of P-N terrain pattern in latitudinal direction(i.e., Loess Tableland type, Loess Hill type, and Transitional Form between Sand and Loess type), whereas there were both lower and higher values for P-N terrain pattern scales in all loess landforms in the longitudinal direction. The P-N terrain pattern alsoclearly presented anisotropy, suggesting that gully networks in the main direction were well-developed while others were relatively undeveloped. In addition, the relationships between the first scales and controlling factors(i.e., gully density, nibble degree, watershed area, mean watershed slope, NDVI, precipitation, loess thickness, and loess landforms) revealed that the first scales are primarily controlled by watershed area and loess landforms. This may indicate that the current spatial pattern of P-N terrains is characterized by internal force. In selecting suitable study areas in China' Loess Plateau, it is crucial to u

关键词： Positive and negative terrains TTLQV Spatial pattern scale Loess landforms Loess Plateau

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Changes in the depths of seasonal freezing and thawing and their effects on vegetation in the Three-River Headwater Region of the Tibetan Plateau

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Journal of Mountain Science 2019年第12期16卷 2810-2827页

作者： WANG Rui DONG Zhi-bao ZHOU Zheng-chao school of Geography and tourism Shaanxi Normal University

Frozen ground degradation plays an important role in vegetation growth and activity in high-altitude cold *** study estimated the spatiotemporal variations in the active layer thickness(ALT)of the permafrost region and the soil freeze depth(SFD)in the seasonally frozen ground region across the Three Rivers Source Region(TRSR)from 1980 to 2014 using the Stefan equation,and differentiated the effects of these variations on alpine vegetation in these two *** results showed that the average ALT from 1980 to 2014 increased by23.01 cm/10 a,while the average SFD decreased by 3.41 cm/10 a,and both changed intensively in the transitional zone between the seasonally frozen ground and *** 1982-2014,the increase in the normalized difference vegetation index(NDVI)and the advancement of the start of the vegetation growing season(SOS)in the seasonally frozen ground region(0.0078/10 a,1.83 d/10 a)were greater than those in the permafrost region(0.0057/10 a,0.39 d/10 a).The results of the correlation analysis indicated that increases in the ALT and decreases in the SFD in the TRSR could lead to increases in the NDVI and advancement of the *** soil moisture played a critical role in vegetation growth in association with the increasing ALT and decreasing *** NDVI for all vegetation types in the TRSR except for alpine vegetation showed an increasing trend that was significantly related to the SFD and *** the study period,the general frozen ground conditions were favorable to vegetation growth,while the average contributions of ALT and SFD to the interannual variation in the NDVI were greater than that of precipitation but less than that of temperature.

关键词： Frozen soil depth Active layer thickness Alpine vegetation Climate warming Three Rivers Source Region

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An Evolutionary Economic Geography Perspective on Types of Operation Development in West Lake, China

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Chinese Geographical Science 2017年第3期27卷 482-496页

作者： YANG Xingzhu ZHA Yanyan LU Lin YANG Yang College of Territorial Resources and tourism Anhui Normal University school of tourism and Hospitality Management Temple University

The types of operation play a key role in facilitating tourism consumption and economic development in a tourism destination. By adopting evolutionary economic geography theory, the paper analyzes the types of operation in West Lake Scenic Area from 1978 to 2013. First, an evolution process consisting of four stages is underpinned, and they are: the new establishment stage, the preliminary development stage, the speedup development stage, and the stabilized maturity stage. Specifically, the distinct characteristics associated with operation types are compared and evaluated at different stages throughout the process. The evolution trees are introduced to scrutinize types of operation development. The results of evolution trees demonstrate the substantial increase in both numbers and types. Second, by applying GIS spatial analysis, the paper also analyzes the spatial evolution characteristics on the types of operation, and the results unveil the co-existence of centripetal and centrifugal forces: the processes of spatial agglomeration and spatial dispersion. More specifically, we recognize the spatial process includes the emergence of node and concentration(1978–1995), the sparse distribution and intensity reduction(1996–2002), the patchy distribution and spatial agglomeration intensification(2003–2008), the dispersed distribution and core area agglomeration(2009–2013). Lastly, path dependence on resource endowment, government and market innovation, knowledge learning and spillover can reasonably explain the types of operation evolution. In conclusion, the evolutionary economic geography theories provide new theoretical and empirical perspectives for tourism policy analysis. At the same time, our comprehensive evidences impart more comprehensive insights and offer useful managerial and policy implications.

关键词： types of operation evolutionary economic geography spatial process West Lake China

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Digital Preservation:A New Approach to Protecting Historical and Cultural Towns and Villages

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Contemporary Social Sciences 2018年第3期3卷 86-96页

作者： Liu Peilin Deng Yunyuan Lin Min(译) Zhang Congrong(译) school of cities and tourism Hengyang Normal University 不详

Digital technology has penetrated all aspects of modern life and is pushing society forward by profoundly changing the way people live and *** can not only eternalize cultural heritage,but also allow relevant knowledge to be spread more quickly and *** is home to a diverse array of historical and cultural towns and villages,which are an important cultural *** preservation means leveraging technologies such as mapping,remote sensing,computers,3 D imaging,virtual reality,plus physical and chemical techniques to collect data to monitor,record,restore,and rebuild with the goal of preserving both their physical shapes and cultural legacies.

关键词： digitization historical and cultural towns and villages 3D technology virtual reality digital legacy

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Scheduling an Energy-Aware Parallel Machine System with Deteriorating and Learning Effects Considering Multiple Optimization Objectives and Stochastic Processing Time

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Computer Modeling in Engineering & Sciences 2023年第4期135卷 325-339页

作者： Lei Wang Yuxin Qi school of Event and Economic Management Shanghai Institute of TourismShanghai201418China school of tourism Shanghai Normal UniversityShanghai201418China

Currently,energy conservation draws wide attention in industrial manufacturing *** recent years,many studies have aimed at saving energy consumption in the process of manufacturing and scheduling is regarded as an effective *** paper puts forwards a multi-objective stochastic parallel machine scheduling problem with the consideration of deteriorating and learning *** it,the real processing time of jobs is calculated by using their processing speed and normal processing *** describe this problem in a mathematical way,amultiobjective stochastic programming model aiming at realizing makespan and energy consumption minimization is ***,we develop a multi-objective multi-verse optimization combined with a stochastic simulation method to deal with *** this approach,the multi-verse optimization is adopted to find favorable solutions from the huge solution domain,while the stochastic simulation method is employed to assess *** conducting comparison experiments on test problems,it can be verified that the developed approach has better performance in coping with the considered problem,compared to two classic multi-objective evolutionary algorithms.

关键词： Energy consumption optimization parallel machine scheduling multi-objective optimization deteriorating and learning effects stochastic simulation

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Effects of a remote,YouTube-delivered exercise intervention on young adults’physical activity,sedentary behavior,and sleep during the COVID-19 pandemic:Randomized controlled trial

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Journal of Sport and Health Science 2022年第2期11卷 145-156,I0002页

作者： Daniel J.McDonough Melina A.Helgeson Wenxi Liu Zan Gao school of Kinesiology University of Minnesota-Twin CitiesMinneapolisMN 55455USA Carlson school of Management University of Minnesota-Twin CitiesMinneapolisMN 55455USA

Background:Public health guidelines have called for innovative and flexible physical activity(PA)intervention strategies to promote PA and health amid the coronavirus disease 2019(COVID-19)***,this study’s purpose was to examine the effects of a home-based,YouTube-delivered PA intervention grounded in self-determination theory on young adults’free-living PA,sedentary behavior,and sleep quality(NCT04499547).Methods:Sixty-four young adults(48 females;age=22.8±3.4 years,mean±SD;body mass index=23.1±2.6 kg/m^(2))were randomized(1:1)into the intervention group,which received weekly aerobic and muscle-strengthening PA videos,or control group,which received weekly general health education videos,for 12 *** primary outcome was free-living moderate-to-vigorous PA(MVPA)and our secondary outcomes were sedentary behavior,light PA,and sleep quality(measured using ActiGraph accelerometers)along with muscle-strengthening PA frequency,self-determination theory-related motivation(non-regulation,external regulation,introjected regulation,identified regulation,integrated regulation,and intrinsic regulation),and perceived PA barriers(assessed using validated questionnaires).Repeated measures analysis of variances(ANOVAs)examined between-group differences at an adjusted significance level of 0.004 and effect sizes as partial eta-squared(η;).Results:We observed statistically significant interaction effects for MVPA,sleep efficiency,muscle-strengthening PA frequency,non-regulation,integrated regulation,intrinsic regulation,and perceived PA barriers(F(1,62)=10.75-77.67,p<0.001-0.002,η_(p)^(2)=0.15-0.56)with all outcomes favoring the intervention *** observed no statistically significant differences in either group for sedentary behavior,light PA,sleep duration,or external,introjected,and identified regulations after 12 weeks(F(1,62)=1.11-3.64,p=0.06-0.61).Conclusion:With national COVID-19 restrictions still in place and uncertainty regarding post-pandemic PA envir

关键词： High-intensity interval training Resistance-training Self-determination theory Social media Video

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Source-sink landscape spatial characteristics and effect on non-point source pollution in a small catchment of the Three Gorge Reservoir Region

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Journal of Mountain Science 2018年第2期15卷 327-339页

作者： WANG Jin-liang NI Jiu-pai CHEN Cheng-long XIE De-ti SHAO Jing-an CHEN Fang-xin LEI Ping school of Resources and Environment Southwest University school of Geography and tourism Chongqing Normal University

The source and sink landscape patterns refer to landscape types or units that can either promote positive evolvement of non-point source(NPS) pollution process, or can prevent/defer the ecological process, respectively. Therefore, the role of a catchment landscape pattern in nutrient losses can be identified based on the spatial arrangement of source and sink landscapes. To reveal the relations between landscape spatial characteristics and NPS pollution in small catchment, a case study was carried out in a Wangjiagou small catchment of the Three Gorges Reservoir Region(TGRR), China. Google earth imagery for 2015 were processed and used to differentiate source and sink landscape types, and six subcatchments were selected as sample regions for monitoring nitrogen and phosphorus *** elevation, slope gradient and relative flow length was used to construct the Lorenz curves of different source and sink landscape types in the catchment, in order to assess the source and sink landscape spatial characteristics. By calculating the location-weighted landscape indices of each subcatchment and total catchment, the landscape spatial load characteristics affecting the NPS pollution was identified, with a further Pearson correlation analysis for location-weighted landscape indices and nitrogen-phosphorus monitoring indicators. The analysis of Lorenz curve has revealed that the obtained distribution trend of Lorenz curve and curve area quantified well the spatial characteristics of source and sink landscape pattern related to the relative elevation, slope gradient and relative flow length in small catchment. Results of Pearson correction analysis indicated that location-weighted landscape index(LWLI) combining of terrain and landscape type factor did better in reflecting the status of nitrogen and phosphorus loss than the indices related to relative elevation, slope gradient and relative flow length.

关键词： Source-sink landscape Non-point sourcepollution Nutrient loss Lorenz curve Landscapeindex Small catchment

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Effects of exergaming on motor skill competence,perceived competence,and physical activity in preschool children

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Journal of Sport and Health Science 2019年第2期8卷 106-113页

作者： Zan Gao Nan Zeng Zachary C.Pope Ru Wang Fang Yu school of Kinesiology University of Minnesota-Twin Cities Department of Food Science and Human Nutrition Colorado State University school of Public Health University of Minnesota-Twin Cities school of Kinesiology Key Laboratory of Exercise and Health Sciences of Ministry of Education Shanghai University of Sport school of Nursing University of Minnesota-Twin Cities

Background: Few school settings offer opportunities for preschool children to engage in structured physical activity, and only a few studies have been conducted examining exergaming's effectiveness on health outcomes in this age group. This study's purpose, therefore, was to examine a school-based exergaming intervention's effect on preschool children's perceived competence(PC), motor skill competence(MSC), and physical activity versus usual care(recess), as well as to examine gender differences for these ***: A total of 65 preschool children from 2 underserved urban schools were assigned to 1 of 2 conditions, with the school as the experimental unit:(1) usual care recess group(8 weeks of 100 min of recess/week(5 days ￡ 20 min)) and(2) exergaming intervention group(8 weeks of100 min of exergaming/week(5 days ￡ 20 min) at school). All children underwent identical assessments of PC, MSC, and moderate-to-vigorous physical activity(MVPA) at baseline and at the end of the 8 th ***: A significant Group ￡ Time effect was observed for MVPA, F(1, 52) = 4.37, p = 0.04, h2 p= 0.04, but not for PC, F(1, 52) = 0.83, p = 0.37,h2 p= 0.02, or MSC, F(1, 52) = 0.02, p = 0.88, h2 p= 0.00. Specifically, the intervention children displayed significantly greater increased MVPA after8 weeks than the comparison children. Additionally, there was a significant time effect for MSC, F(1, 52) = 15.61, p schoolers' MSC improved across time, boys demonstrated greater MVPA than girls at both time ***: Exergaming showed a positive effect in promoting preschool children's MVPA at school and has the potential to enhance PC and MSC. More research with larger sample sizes and longer study durations are warranted.

关键词： Active video games Childhood obesity Gender differences Moderate-to-vigorous physical activity Recess

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Numerical modeling of solute transport in deformable unsaturated layered soil

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Water Science and Engineering 2017年第3期10卷 184-196页

作者： Sheng Wu Dong-sheng Jeng cities Research Institute Griffith School of EngineeringGriffith UniversitySouthport 4222Australia

The effect of soil stratification was studied through numerical investigation based on the coupled model of solute transport in deformable unsaturated soil. The theoretical model implied two-way coupled excess pore pressure and soil deformation based on Biot's consolidation theory as well as a one-way coupled volatile pollutant concentration field developed from the advection-diffusion theory. Embedded in the model, the degree of saturation, fluid compressibility, self-weight of the soil matrix, porosity variance, longitudinal dispersion, and linear sorption were computed. Based on simulation results of a proposed three-layer landfill model using the finite element method, the multi-layer effects are discussed with regard to the hydraulic conductivity, shear modulus, degree of saturation, molecular diffusion coefficient, and thickness of each layer. Generally speaking, contaminants spread faster in a stratified field with a soft and highly permeable top layer; soil parameters of the top layer are more critical than the lower layers but controlling soil thicknesses will alter the results. This numerical investigation showed noticeable impacts of stratified soil properties on solute migration results, demonstrating the importance of correctly modeling layered soil instead of simply assuming the averaged properties across the soil profile.

关键词： Solute transport Layered soil Consolidation Unsaturated soil Deformable media

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Predicting and assessing changes in NPP based on multi-scenario land use and cover simulations on the Loess Plateau

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Journal of Geographical Sciences 2021年第7期31卷 977-996页

作者： JIANG Xiaowei BAI Jianjun school of Geography and tourism Shaanxi Normal UniversityXi'an 710119China

Land use/cover change(LUCC)is a major factor affecting net primary production(NPP).According to the LUCC of the Loess Plateau from 2005 to 2015,the LUCC patterns in 2025 in three scenarios were predicted by using the Future Land Use Simulation(FLUS)***,taking the average NPP of various land use/cover types in 16 years as the reference scale,the changes in NPP in multi-scenario simulations are predicted and analyzed,and the impact of different land use/cover transfers on NPP is *** results are as follows:(1)The land use/cover changes greatly in the baseline and fast development scenarios,and changes relatively little in the ecological protection scenarios.(2)The changes in NPP in different scenarios reflected the significant difference in the ecological protection *** the three scenarios promote an NPP increase,but the ecological protection scenario can promote NPP increases the most.(3)The changes in NPP caused by LUCC in the three scenarios reflected the significant difference in the various land use/cover types protection *** and predicting NPP changes in multi-scenario LUCC simulations in the future can provide a theoretical basis for decision makers to judge the future changes in ecological environments and ecological protection effects against different policy backgrounds.

关键词： net primary production(NPP) scenario simulation land use/cover change(LUCC) Loess Plateau

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