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Flagstaff Urban Trails System and Its Inspiration for the Construction of China National Trails System 被引量:1
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作者 HU Haisheng ZHENG Yanping 《Journal of Landscape Research》 2014年第2期1-3,10,共4页
Flagstaff Urban Trails System(FUTS) is a city-wide network of non-motorized, shared-use pathways that are used by bicyclists, walkers, hikers, runners, and other users for both recreation and transportation. FUTS tota... Flagstaff Urban Trails System(FUTS) is a city-wide network of non-motorized, shared-use pathways that are used by bicyclists, walkers, hikers, runners, and other users for both recreation and transportation. FUTS totals 79.2 km in Flagstaff, the Flagstaff government approved the fi rst plan in 1988, and FUTS Trail Priority Evaluation 2011 outlined the evaluation criteria, trail rankings and ranking results The new FUTS Master Plan shows about 130-km planned trails, and creates an ultimate trail system about 210 km. FUTS management organization and Transportation Tax Program is the key to keep the successful works of FUTS. Status quo of China National Trails System(CNTS) is reviewed as: scenic areas have relatively sound trail systems, but there is no any standard system; green corridors within the urban and rural system become popular, but there is no connection system. The development of China National Trails System can be promoted in 3 aspects: establishing national trails system, planning and design trails comprehensively, stressing daily operation and management. 展开更多
关键词 TRAIL Flagstaff Urban trails system(FUTS) China National trails system(CNTS)
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Factors determining changes in the network of marked hiking trails in the Sudetes
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作者 Krzysztof KOŁODZIEJCZYK 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1075-1099,共25页
Hiking trails are a basic type of tourist infrastructure,which,on the one hand,make areas available for tourist traffic,and on the other hand,can contribute to the protection of the natural environment(if they are wel... Hiking trails are a basic type of tourist infrastructure,which,on the one hand,make areas available for tourist traffic,and on the other hand,can contribute to the protection of the natural environment(if they are well designed and maintained).Owing to the variety of performed functions,their designation is determined by several factors:natural,technical,economic,social.Networks of trails change constantly.The aim of this article is to determine exactly what factors influence transformations within the hiking trail networks and what is their significance.To this end,three study areas in the Sudetes were analysed:one on the Polish side of the Sudetes-the Table(Stołowe)Mountains,and two on the Czech side-the rock town near the village of Sloup vČechách and the central part of Zlatohorskávrchovina.An analysis of changes in the shape of the networks over time was carried out,as well as surveys of institutions that were responsible for or influenced these transformations.These areas are characterised by a significant level of changes in the trail network.Among the factors influencing these changes,the tourist attractiveness of the area,the resilience of the environment,the intensity of tourism traffic,the environmental transformations associated with it,the history of tourism development and land ownership changes should be considered the most important.At each stage of forming networks,the key factor should be tourists’needs,including the desire to escape the urbanised environment.For this reason,trails should avoid roads with artificial(hard)surfaces and heavy automobile traffic. 展开更多
关键词 Hiking trails Trail networks Graphs Tourist traffic SUDETES
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Exercise-based rehabilitation programmes for pulmonary hypertension:a systematic review and meta-analysis of randomized controlled trails
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作者 Lu Yan Qingyun Yan Zhihong Liu 《中国循环杂志》 CSCD 北大核心 2018年第S01期167-168,共2页
Objective Individuals with pulmonary hypertension(PH)have reduced exercise capacity and quality of life.Exercise-based rehabilitation may have beneficial effects to improve the exercise capacity and quality of life in... Objective Individuals with pulmonary hypertension(PH)have reduced exercise capacity and quality of life.Exercise-based rehabilitation may have beneficial effects to improve the exercise capacity and quality of life in patients with PH.We aim to assess the efficacy and safety of exercised-based rehabilitation for people eith PH by performing a randomized controlled trails(RCTs)meta-analysis of exercised-based rehabilitation for people with PH by performing a randomized controlled trails meta-analysis. 展开更多
关键词 PULMONARY hypertension RANDOMIZED CONTROLLED trails trails META-ANALYSIS
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COPD患者血清TRAIL表达水平及与炎症因子和肺功能的相关性
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作者 杨刚 周琴 赵雪林 《中国急救复苏与灾害医学杂志》 2024年第10期1349-1352,共4页
目的探讨慢性阻塞性肺疾病(COPD)患者血清肿瘤坏死因子相关凋亡诱导配体(TRAIL)与炎症因子和肺功能的关系。方法选取2020年6月—2022年12月在本院治疗的200例COPD患者为观察组,200例健康体检志愿者为对照组。根据COPD诊治指南中疾病类... 目的探讨慢性阻塞性肺疾病(COPD)患者血清肿瘤坏死因子相关凋亡诱导配体(TRAIL)与炎症因子和肺功能的关系。方法选取2020年6月—2022年12月在本院治疗的200例COPD患者为观察组,200例健康体检志愿者为对照组。根据COPD诊治指南中疾病类型分为急性加重期组140例,稳定期组60例。分析血清TRAIL水平与炎症因子[超敏-C反应蛋白(hs-CRP)、降钙素原(PCT)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)]水平、肺功能[1秒用力呼气容积占比(FEV_(1)%)、FEV_(1)和用力肺活量(FVC)比值、肺一氧化碳弥散量占比(DLCO%)及呼气峰流速(PEF)]的关系。结果与对照组相比,稳定期组、急性加重期组患者血清TRAIL、hs-CRP、PCT、IL-6、TNF-α水平显著升高(P<0.05),FEV_(1)%、FEV_(1)/FVC、DLCO%、PEF明显降低(P<0.05);急性加重期组较稳定期组患者血清TRAIL、hs-CRP、PCT、IL-6、TNF-α水平明显升高(P<0.05),FEV_(1)%、FEV_(1)/FVC、DLCO%、PEF显著降低(P<0.05);多因素线性回归分析结果显示,TRAIL水平与hs-CRP、TNF-α、FEV_(1)/FVC和DLCO水平有关(P<0.05);经Pearson法分析,COPD患者血清TRAIL水平与hs-CRP、TNF-α均呈正相关(r=0.412,0.527,P<0.05),与FEV_(1)/FVC、DLCO%均呈负相关(r=-0.594,-0.476,P<0.05)。结论COPD患者血清TRAIL水平升高,其与患者炎症因子和肺功能密切相关。 展开更多
关键词 慢性阻塞性肺疾病 TRAIL 炎症因子 肺功能
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Research on Developing an Assessment Scale for Tourism Experience Elements of Ancient Shu Road Heritage Trail
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作者 Wang Yuan Wang Bo Zhou Jiang 《Contemporary Social Sciences》 2024年第5期118-142,共25页
Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse them... Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse thematic variations,and considerable tourist appeal,these paths have emerged as representative heritage trails,increasingly transforming into a novel tourism product experience that is highly favored by tourists and recognized by government authorities.However,research on ancient roads for tourism in China currently lacks a systematic theoretical framework,as well as relevant policies,regulations,and standards to guide their practical development.Therefore,there is a pressing need to draw upon international best practices and conduct foundational research to develop an experience element system that aligns with the perceptions,behaviors,and consumption characteristics of Chinese tourists,thereby advancing theoretical exploration in this field.This study focuses on the representative Ancient Shu Road as a case study and employs a mixed-method approach that integrates qualitative and quantitative research.It aims to construct a tourist-centric scale for the experience elements of ancient road tourism while analyzing the interactive relationship between these experience elements and tourist needs.This study addresses a significant gap in the development of indicator systems for domestic studies of ancient road tourism experiences.Ultimately,the study establishes a comprehensive scale that encompasses three core categories—trail resources and environment,facilities and services,and modes of tourism activities—along with eight primary dimensions:core resources,surrounding cultural environment,surrounding natural environment,tourism reception facilities and services,infrastructure and support services,information facilities and information services,and outdoor and recreational activities.This scale consists of thirty-two specific items,providing a robust reference for future research endeavors.Additionally,the study proposes specific development strategies related to key mechanisms,spatial configuration,and facility construction to enhance the overall development of ancient road tourism. 展开更多
关键词 ancient roads heritage trails tourism experience elements scale development
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Evaluation of the Shallow Gas Hydrate Production Based on the Radial Drilling-Heat Injection-Back Fill Method
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作者 CHEN Qiang WAN Yizhao +6 位作者 WU Nengyou SUN Jianye WANG Jian LIU Changling LI Yanlong LI Chengfeng HU Gaowei 《Journal of Ocean University of China》 CAS CSCD 2024年第1期119-128,共10页
It has been evidenced that shallow gas hydrate resources are abundant in deep oceans worldwide.Their geological back-ground,occurrence,and other characteristics differ significantly from deep-seated hydrates.Because o... It has been evidenced that shallow gas hydrate resources are abundant in deep oceans worldwide.Their geological back-ground,occurrence,and other characteristics differ significantly from deep-seated hydrates.Because of the high risk of well construction and low production efficiency,they are difficult to be recovered by using conventional oil production methods.As a result,this paper proposes an alternative design based on a combination of radial drilling,heat injection,and backfilling methods.Multi-branch holes are used to penetrate shallow gas hydrate reservoirs to expand the depressurization area,and heat injection is utilized as a supplement to improve gas production.Geotechnical information collected from an investigation site close to the offshore production well in the South China Sea is used to assess the essential components of this plan,including well construction stability and gas production behavior.It demonstrates that the hydraulic fracturing of the 60mbsf overburden layer can be prevented by regulating the drilling fluid densities.However,the traditional well structure is unstable,and the suction anchor is advised for better mechanical performance.The gas produc-tion rate can be significantly increased by combining hot water injection and depressurization methods.Additionally,the suitable produc-tion equipment already in use is discussed. 展开更多
关键词 shallow gas hydrate trail production radial drilling-heat injection-back fill method experimental and numerical simulation
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Remodeling tumor microenvironment using pH-sensitive biomimetic co-delivery of TRAIL/R848 liposomes against colorectal cancer
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作者 YONGJIAN HUANG JINZHOU WANG +1 位作者 JIUHUA XU NING RUAN 《Oncology Research》 SCIE 2024年第11期1765-1776,共12页
Background:Despite significant advancements in the development of anticancer therapies over the past few decades,the clinical management of colorectal cancer remains a challenging task.This study aims to investigate t... Background:Despite significant advancements in the development of anticancer therapies over the past few decades,the clinical management of colorectal cancer remains a challenging task.This study aims to investigate the inhibitory effects of cancer-targeting liposomes against colorectal cancer.Materials and Methods:Liposomes consisting of 3β-[N-(N′,N′-dimethylamino ethane)carbamoyl]-cholesterol(DC-CHOL),cholesterol(CHOL),and dioleoylphosphatidylethanolamine(DOPE)at a molar ratio of 1:1:0.5 were created and used as carriers to deliver an apoptosis-inducing plasmid encoding the tumor necrosis factor-related apoptosis-inducing ligand(pTRAIL)gene,along with the toll-like receptor(TLR7)agonist Rsiquimod(R848).The rationale behind this design is that pTRAIL can trigger cancer cell apoptosis by activating the DR4/5 receptor,while R848 can stimulate the immune microenvironment.Results:Experimental results demonstrated the synergistic effects of R848 and pTRAIL encapsulated by liposomes(RTL)in suppressing the proliferation of colorectal cancer cells.Moreover,further in vivo investigations revealed the strong anti-tumor efficacy of RTL in xenograft and orthotropic in situ models of colorectal cancer.Conclusions:These findings collectively highlight the therapeutic potential of R848/pTRAIL-loaded liposomes in the treatment of colorectal cancer. 展开更多
关键词 Colorectal cancer Plasmid TRAIL(pTRAIL) R848 Tumor-associated macrophages
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Influence of layout of scanners on intelligent mine scanning trails
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作者 李大勇 赵俊利 +1 位作者 王妍 王立君 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期229-234,共6页
To expand scanning area and attack range without changing the inner structure of intelligent warhead, a new arrangement mode of the scanner for intelligent mine is proposed. The required coordinate systems are es... To expand scanning area and attack range without changing the inner structure of intelligent warhead, a new arrangement mode of the scanner for intelligent mine is proposed. The required coordinate systems are established firstly on the basis of advanced dynamics principle. and the exterior ballistics equations are deduced. Then the equations of scanning trails are established by the method of space analytic geometry. To get the scanning trails. the differential equations are transformed into discrete simulation model using the algorithm of fourth order Runge-Kutta and then are simulated using Matlab. Compared with the scanning trails obtained by the traditional layout of scanner, the scanning trails obtained by the proposed layout of scanner has larger horizontal range of scanning circle and bigger trarget acquisition probability. Therefore, the new arrangement mode of the scanner for intelligent mine can increase attack range. 展开更多
关键词 intelligent mine SCANNER scanning trails exterior ballistics
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美国信息能力在线测评SAILS和TRAILS简介 被引量:3
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作者 李耀俊 《信息系统工程》 2010年第1期115-116,134,共3页
美国肯特州立大学设计的信息素养能力标准评估项目SAILS和信息素养能力实时测评量表TRAILS,可用于评估大、中学生的信息知识和能力水平。作为标准化测试项目,它们具有较高的信度和效度,实施管理简便,能提供内部和外部评价比较。
关键词 信息素养 SAILS trails 标准化工具
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Performance of the walking trail making test in older adults with white matter hyperintensities
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作者 Hong-Yi Zhao Zhi-Qiang Zhang +2 位作者 Yong-Hua Huang Hong Li Fang-Yuan Wei 《World Journal of Psychiatry》 SCIE 2024年第1期102-110,共9页
BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothes... BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothesized that WTMT performance would be altered in older adults with white matter hyperintensities(WMH).AIM To explore the performance in the WTMT in older people with WMH.METHODS In this single-center,observational study,25 elderly WMH patients admitted to our hospital from June 2019 to June 2020 served as the WMH group and 20 participants matched for age,gender,and educational level who were undergoing physical examination in our hospital during the same period served as the control group.The participants completed the WTMT-A and WTMT-B to obtain their gait parameters,including WTMT-A completion time,WTMT-B completion time,speed,step length,cadence,and stance phase percent.White matter lesions were scored according to the Fazekas scale.Multiple neuropsychological assessments were carried out to assess cognitive function.The relationships between WTMT performance and cognition and motion in elderly patients with WMH were analyzed by partial Pearson correlation analysis.RESULTS Patients with WMH performed significantly worse on the choice reaction test(CRT)(0.51±0.09 s vs 0.44±0.06 s,P=0.007),verbal fluency test(VFT,14.2±2.75 vs 16.65±3.54,P=0.012),and digit symbol substitution test(16.00±2.75 vs 18.40±3.27,P=0.010)than participants in the control group.The WMH group also required significantly more time to complete the WTMT-A(93.00±10.76 s vs 70.55±11.28 s,P<0.001)and WTMT-B(109.72±12.26 s vs 82.85±7.90 s,P<0.001).WTMT-A completion time was positively correlated with CRT time(r=0.460,P=0.001),while WTMT-B completion time was negatively correlated with VFT(r=-0.391,P=0.008).On the WTMT-A,only speed was found to statistically differ between the WMH and control groups(0.803±0.096 vs 0.975±0.050 m/s,P<0.001),whereas on the WTMT-B,the WMH group exhibited a significantly lower speed(0.778±0.111 vs 0.970±0.053 m/s,P<0.001)and cadence(82.600±4.140 vs 85.500±5.020 steps/m,P=0.039),as well as a higher stance phase percentage(65.061±1.813%vs 63.513±2.465%,P=0.019)relative to controls.CONCLUSION Older adults with WMH showed obviously poorer WTMT performance.WTMT could be a potential indicator for cognitive and motor deficits in patients with WMH. 展开更多
关键词 White matter hyperintensities Cognitive dysfunction Motor deficits Gait analysis Trail making test Small vessel disease
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Xiamen Mountains-to-Sea Trail
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作者 吕静钰 郭金涛(指导) 《疯狂英语(初中天地)》 2024年第9期72-73,共2页
Xiamen,a coastal city famous for its impressive seascape,draws numerous tourists each year.One of the prime locations to appreciate the city’s beauty is the Mountains-to-Sea Trail,an approximately 23-kilometer-long p... Xiamen,a coastal city famous for its impressive seascape,draws numerous tourists each year.One of the prime locations to appreciate the city’s beauty is the Mountains-to-Sea Trail,an approximately 23-kilometer-long pedestrian corridor that offers a unique experience for visitors. 展开更多
关键词 XIAMEN TRAIL COASTAL
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Swiss cycling brand to pushing the boundaries of sustainability
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《China Textile》 2024年第3期47-47,共1页
Possenia,a trailblazing newcomer in the cycling industry,proudly announces a groundbreaking achievement:it is Switzerland’s first cycling brand to introduce the bluesign®PRODUCT label,marking an important milest... Possenia,a trailblazing newcomer in the cycling industry,proudly announces a groundbreaking achievement:it is Switzerland’s first cycling brand to introduce the bluesign®PRODUCT label,marking an important milestone in sustainable cycling apparel in Europe.These environmentally conscious,premium cycling essentials are now available on Digitec Galaxus as well as directly through Possenia’s own website. 展开更多
关键词 CYCLING TRAIL BREAKING
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Technology Guides The Way
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作者 ZHANG JIANZHEN LIN XIAOFENG 《ChinAfrica》 2024年第11期34-35,共2页
Climate change is a pressing challenge that humanity faces at present.As a participant,contributor and trailblazer in global ecological conservation,China is committed to implementing multilateralism and fostering a f... Climate change is a pressing challenge that humanity faces at present.As a participant,contributor and trailblazer in global ecological conservation,China is committed to implementing multilateralism and fostering a fair system of global environmental governance.With abundant resources and a large population,Africa,the second-largest continent,faces significant challenges in addressing climate change and protecting the environment due to limited socio-economic development and technological infrastructure. 展开更多
关键词 TRAIL abundant HUMANITY
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Networks of hiking tourist trails in the Krkono?e(Czech Republic) and Peneda-Gerês(Portugal) national parks-comparative analysis 被引量:6
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作者 Krzysztof KO?ODZIEJCZYK 《Journal of Mountain Science》 SCIE CSCD 2019年第4期725-743,共19页
Tourist trails as a linear form of tourist infrastructure fulfill various functions(i.e. recreational, ecological, economic, social, ensuring safety). They are especially important in national parks, where in selected... Tourist trails as a linear form of tourist infrastructure fulfill various functions(i.e. recreational, ecological, economic, social, ensuring safety). They are especially important in national parks, where in selected areas tourist penetration is allowed only along specially designed, official routes. A well-planned layout of tourist trails with appropriate facilities can help to limit the negative consequences of tourist pressure on protected natural areas. The aim of the article is a comparison of offers for active tourists in two mountain national parks(the Krkono?e National Park in the Czech Republic and the Peneda-Gerês National Park in Portugal), taking into consideration the marked hiking trails – the most frequently used type of tourist trails. As a result the level of area coverage by the networks of hiking trails was assessed, as well as their adequateness towards the needs of tourists. The descriptive analysis was based on author's personal observations. In the examination of hiking trails as part of a system, some elements of the graph theory were used, especially coefficients for topologic analysis of spatial structure. This method enables simplification of a network, comparison of various areas and making some assumptions concerning tourist infrastructure, which is a crucial factor while analyzing trails from a tourists' point of view. In both analyzed national parks the relief is quite similar, as well as their locations near national borders, what justifies the choice of the areas scrutinized in the paper. What differ them are patterns of tourism development and the current ways of undertaking active tourism. Not similarities but the two latter factors resulted in a distinct character of the two compared networks of trails and facilities connected with them. The system of hiking trails and tourist infrastructure seem better developed in the Krkono?e National Park, what can be explained by historical and social conditions, especially the adopted model of hiking. In the article some disadvantages of tourist infrastructure in both protected areas were presented, as well as some suggestions in terms of its development, resulting from the analysis of networks of hiking trails. 展开更多
关键词 HIKING TOURIST trails TOURIST infrastructure MOUNTAINS National parks Network Graph analysis
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Status and outlook of hiking trails in the central part of the Low Tatra Mountains in Slovakia between 1980–1981 and 2013–2014 被引量:3
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作者 HRNCIAROVá Tatiana KENDERESSY Pavol +3 位作者 SPULEROVá Jana VLACHOVICOVá Miriam PISCOVá Veronika DOBROVODSKá Marta 《Journal of Mountain Science》 SCIE CSCD 2018年第8期1615-1632,共18页
This study presents a methodology for assessment of the condition of hiking trails(HTs) and their impact zones in the central part of the Low Tatra mountain range, based on comparison of two complex data sets gathered... This study presents a methodology for assessment of the condition of hiking trails(HTs) and their impact zones in the central part of the Low Tatra mountain range, based on comparison of two complex data sets gathered in 33 years apart. The first field investigation was performed in 1980 and 1981, and the second in 2013 and 2014. The main goal was to perform a landscape typology in order to assess the susceptibility of landscape complexes to occurrence of anthropogenic and natural destruction processes and to assess the condition and prospects of HTs and their impacts on the adjacent alpine environment. Landscape complexes were characterised by selected abiotic, biotic and technical parameters of HTs and their impact zones. Due to the high variability of these parameters over the length of the HTs, we had to decide on how to map them. This was done using a square grid with 100 m-sized cells. For each cell with HT, the parameters were assigned the typical value within that cell. In total, 26.3 km of HT were studied, stretching over 266 grid cells. On comparison of the two data sets, it was seen that, 64%(171 grid cells) display a generally positive condition, with 54%(143 grid cells) even exhibiting significant improvement or continuously positive state of their condition. 36%(95 grid cells) were in bad condition, including 3%(9 grid cells) whose state had deteriorated, and 2%(6 grid cells) whose state had significantly deteriorated, in the time between the two assessments. 展开更多
关键词 Hiking trails Degradation Tourist pressure Monitoring hiking trail changes Low Tatras Mountains Slovakia
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Changes in the network of tourist trails in the border zones of the Czech Republic after entering the Schengen area 被引量:3
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作者 Krzysztof KOLODZIEJCZYK 《Journal of Mountain Science》 SCIE CSCD 2020年第4期949-972,共24页
Among the factors influencing tourist trail network development are political issues, including the presence of state borders, the possibility of crossing them and the accessibility of border zones. In the article, it... Among the factors influencing tourist trail network development are political issues, including the presence of state borders, the possibility of crossing them and the accessibility of border zones. In the article, it was decided to look at changes in the offer of tourist trails(hiking and cycling) along the entire border of the Czech Republic after the extension of the Schengen area(within this area, crossing the border is possible anywhere, and not only at official border crossings). It should be emphasized here that the borders of the Czech Republic over most of their length run through mountainous areas and, apart from political factors, natural features should have a major impact on the development of tourist routes. In order to determine the coherence of the current network of trails on both sides of the Czech Republic state border, modern tourist maps have been analyzed, determining the number of places where it is possible to cross the state border with the help of a marked tourist trail. Based on that, two indicators were introduced to determine the degree of openness with all neighboring countries as regards the opportunity to cross on a tourist trail. Changes in the historical situation, a comparison of the accessibility of the border area before entering the Schengen area and 2019, were analyzed for two study areas using archival maps. Over a decade after the extension of the Schengen area, the number of places where tourist trails of neighboring countries approach the border has clearly increased. Crossing is more often made possible using hiking trails than cycling routes(trails of the first type cross the border every 7.91 km, while the latter every 13.3 km), but considering the speed of movement, it can be assessed that the openness for cyclists is higher than for hikers. Moreover, in many places there is still significant potential for further integration of tourist trail networks as trails created in one country often do not have a continuation on the other side of the border. 展开更多
关键词 Tourist trails Schengen area Border zone MOUNTAINS Czech Republic
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ANALYSIS ON MOTION STABILITY OF A HIGH-SPEED ROTOR-BEARING SYSTEM 被引量:2
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作者 ZhangJunhong SunShaojun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第2期220-223,共4页
A non-linear dynamic model of one type of high-speed rotor system with gassupporting system is set up. The laws between the capacity force and the parameters of bearing, thestatic equilibrium position and rotating spe... A non-linear dynamic model of one type of high-speed rotor system with gassupporting system is set up. The laws between the capacity force and the parameters of bearing, thestatic equilibrium position and rotating speed are studied on the basis of above model. Then, thefailure rotating, speed is given in the working state, and the relation between the minimum failurerotating speed and clearance of bearing is also studied. At last, the stability and failurecondition are discussed in different working conditions. 展开更多
关键词 Gas bearing Rotor system Motion stability Axes trail
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A Defect Formation as Snail Trails in Photovoltaic Modules 被引量:2
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作者 Han-Chang Liu Chung-Teng Huang +2 位作者 Wen-Kuei Lee Shih-Siang Yan Fu-Ming Lin 《Energy and Power Engineering》 2015年第8期348-353,共6页
In this paper, we discussed the field failures of the brownish discolored lines like snail trails in PV modules. We were successful simulation snail trails in laboratory and outdoor field. We had found out some types ... In this paper, we discussed the field failures of the brownish discolored lines like snail trails in PV modules. We were successful simulation snail trails in laboratory and outdoor field. We had found out some types EVA (ethylene vinyl acetate) encapsulants and back sheets which had the serious snail trails but others were snail trails free. Furthermore, according to IEC 61215 accelerated aging testing, we also found only within 2% power loss after these modules impacted by snail trails. The main power losses over 5% were come from cell micro cracks before snail trail formation. That snail trails occurrence means solar cells should have micro cracks. In here, we contributed the snail trail effects and avoided the failures in future photovoltaic modules performance. 展开更多
关键词 SNAIL trails Micro CRACK EVA (Ethylene VINYL Acetate)
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Soil physical properties degrade further on skid trails in the year following operations 被引量:1
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作者 Ramin Naghdi Ahmad Solgi +1 位作者 Eric K.Zenner Farshad Keivan Behjou 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第1期93-101,共9页
Short-term recovery of soil physical properties on skid trails was investigated upon cessation of skidding operations and 1 year later. Bulk density and porosity were assessed at three levels of traffic intensity and ... Short-term recovery of soil physical properties on skid trails was investigated upon cessation of skidding operations and 1 year later. Bulk density and porosity were assessed at three levels of traffic intensity and two slope gradients. Compared to undisturbed areas, bulk density increased, total porosity and macroporosity decreased, and microporosity increased in the compacted areas immediately after skidding. In all cases, changes were significantly greater when traffic intensity was higher and when slopes were steeper. Surface soil compaction did not show any recovery over the 1-year period, illustrating the persistent effects of compaction on soil structure. In fact, surficial compaction further increased and macroporosity further decreased after 1 year of recovery, compared to immediately after skidding. While these changes may reflect inherent small-scale site variability or differences in soil moisture content at times of sampling, direct negative physical impacts on newly exposed soil(such as by raindrops), in addition to the loss of organic matter after canopy removal and skidding, likely delayed any physical recovery, particularly on heavily trafficked trails on steeper slopes. These results raise serious concerns about longterm resilience to traffic on forest soils and indicate the necessity to properly retire skid trails to avoid further soil degradation as trails age. 展开更多
关键词 COMPACTION POROSITY Recovery Skid trail slope Traffic frequency
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TRAILS ON A REGULAR DIFFUSION-LIMITED AGGREGATION FRACTAL 被引量:1
20
作者 WANG Xiaomin ZHENG Dafang +1 位作者 LIN Zhifang TAO Ruibao 《Chinese Physics Letters》 SCIE CAS CSCD 1990年第5期193-196,共4页
By an exact renormalization method the trail problem on a regular fractal for the diffusion-limited aggregation is considered,and the mean square end-toend distance critical exponent v is obtained.It is indicated that... By an exact renormalization method the trail problem on a regular fractal for the diffusion-limited aggregation is considered,and the mean square end-toend distance critical exponent v is obtained.It is indicated that self-avoiding trails and self-avoiding walks are in different universality classes on this irreversible kinetic growth fractal. 展开更多
关键词 REG IRREVERSIBLE TRAIL
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