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High Voltage 2023年第3期8卷 570-582页

作者： Yong Liu Chao Li Fanghui Yin Boxue Du Masoud Farzaneh School of Electrical and Information Engineering Tianjin UniversityTianjinChina Shenzhen International Graduate School Tsinghua UniversityShenzhenChina University of Quebec at Chicoutimi ChicoutimiQuebecCanada

In order to improve the stability and reliability of high voltage direct current(HVDC)transmission lines in cold regions,this article investigated the corona discharges and the icicle growth characteristics on outdoor insulators under DC voltages.The experiments were conducted at CIGELE laboratory at University of Quebec.The simulation model of corona discharges and the theoretical model of icicle growth were established.The dynamic process and interactive characteristics between the icicle growth and corona discharges under different HVDC voltages were obtained.The results showed that the discharge activity was strong and the cooling effect of ionic air was weak under negative DC voltage,resulting in a large number of bubbles inside the icicle.More negative ions were produced under negative DC voltage,which enhanced the polarisation of water droplets,leading to a greater density of ice beads outside the icicles.In addition,the longest icicles of each insulator under high humidity could bridge the shed gap.The accumulated charge and leakage current were higher under negative DC voltage,as well as the corona discharge at the top of the icicles lasted longer.Therefore,the negative DC corona discharge more significantly inhibited the growth of the icicle,resulting in a slower growth rate of the icicles.

关键词： insulator characteristics outdoor

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开普敦狂欢节

疯狂英语（新悦读） 2024年第5期 11-13,73页

作者：孙启禄山东

主题语境:节日文化篇幅:335词建议用时:6分钟1 As one of the city􀆳s most popular free outdoor events,the Cape Town Carnival is a multicultural celebration which focuses on social inclusion and bridging the divide between the diverse communities of the Western Cape and specifically Cape Town.It􀆳s a celebration of the many diverse cultures which makes Cape Town stand out from the most world⁃famous cities.The carnival is considered as a community participation event by the western Cape government and draws bigger crowds each year.

关键词： diverse participation outdoor

Evaluation and impact factors of indoor and outdoor gas-phase nitrous acid under different environmental conditions

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Journal of Environmental Sciences 2020年第9期32卷 165-171页

作者： Yan Chen Weigang Wang Chaofan Lian Chao Peng Wenyu Zhang Junling Li Mingyuan Liu Bo Shi Xuefei Wang Maofa Ge State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences(BNLMS)CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of ScienceXiamen 361021China

As an important indoor pollutant,nitrous acid(HONO) can contribute to the concentration of indoor OH radicals by photolysis via sunlight penetrating into indoor environments,thus affecting the indoor oxidizing capability.In order to investigate the concentration of indoor HONO and its impact factors,three different indoor environments and two different locations in urban and suburban areas were selected to monitor indoor and outdoor pollutants simultaneously,including HONO,NO,NO2,nitrogen oxides(NOx),O3,and particle mass concentration.In general,the concentration of indoor HONO was higher than that outdoors.In the urban area,indoor HONO with high average concentration(7.10 ppbV) was well-correlated with the temperature.In the suburban area,the concentration of indoor HONO was only about 1-2 ppbV,and had a good correlation with indoor relative humidity.It was mainly attributed to the heterogeneous reaction of NO2 on indoor surfaces.The sunlight penetrating into indoor environments from outside had a great influence on the concentration of indoor HONO,leading to a concentration of indoor HONO close to that outdoors.

关键词： impact environments outdoor

The next GORE-TEX for jackets?

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China Textile 2024年第2期 14-14页

Columbia is a world-renowned manufacturer of outdoor products.Its product range covers all aspects of outdoor equipment such as jackets,down jackets,outdoor footwear,backpacks and accessories.In the outdoor industry,Columbia was the first brand to propose a three-in-one garment design concept.This practical design has since been adopted by almost every outdoor brand.The Columbia Jacket is positioned for urban outdoor recreation.Its rugged materials and design make it suitable for low-altitude outdoor sports as well as urban commuting.

关键词： outdoor altitude jacket

An assessment of the climatic suitability of Afriski Mountain Resort for outdoor tourism using the Tourism Climate Index(TCI)

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Journal of Mountain Science 2019年第11期16卷 2453-2469页

作者： Kirsten NOOME Jennifer M.FITCHETT School of Geography Archaeology and Environmental Studies University of the Witwatersrand

Tourism Climatic Indices(TCIs)are widely used in the global North to quantify the climatic suitability of a destination for tourism.Only one such study has been conducted in southern Africa to date.It is in a chronic shortage of research on tourism and climate change in the southern hemisphere.This study presents the application of the TCI in Lesotho,calculated for the eastern Lesotho Highlands.The region has an emerging tourism sector,which primarily comprises outdoor activities.These include hiking,horse-riding,music festivals,mountain biking,cultural visits,sightseeing,and at the Afriski lodge,skiing and snowboarding.These activities are reliant on climatic conditions that are conducive to the activity taking place,prolonged periods outdoors,and tourist satisfaction of the activity.Climate is a major determinant of both the length of season for these activities and the timing of peak tourist arrivals.Rising temperatures and changes in relative humidity and precipitation pose real threats to hiking,sightseeing and snow tourism at Afriski.The reliance of tourism in the region on specific climatic conditions for successful tourism prompted the use of the TCI.TCI results classify the eastern Lesotho Highlands as having‘good'climatic conditions with an overall TCI score of 64 for the period 2012-2017.Monthly TCI scores for the eastern Lesotho reveal a bimodal-shoulder,meaning the peak climatic conditions are in the regional summer months(December to February).This conflicts with the peak tourist seasons of summer and winter,which align with South African school holidays,and the timing of the most profitable tourism activity(skiing)which occurs during the winter months of June,July and August.Lesotho is landlocked by South Africa.TCI analysis for South Africa reveals more suitable climatic conditions for tourism than Lesotho,with significantly higher scores of 80-89.

关键词： Climate Tourism Climatic Index(TCI) Lesotho Highlands outdoor tourism Snow tourism

outdoor Sports Still Has Huge Potential to Develop

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China's Foreign Trade 2022年第6期 33-35页

作者： Joe Zhang 不详

In recent years,more and more people have been taking part in outdoor sports,due to the influence of both the COVID-19pandemic and rising health awareness.A variety of new activities,such as elaborate camping by the lake,exploratory cycling in the city and ultimate frisbee on the lawn,have gradually endowed outdoor sports with new features such as strong social interaction,a low participation threshold,as well as leisure and entertainment.

关键词： cycling endowed outdoor

Associations between near work, outdoor activity, parental myopia and myopia among school children in Aba, Nigeria

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International Journal of Ophthalmology(English edition) 2020年第2期13卷 309-316页

作者： Uchenna Chigozirim Atowa Samuel Otabor Wajuihian Alvin Jeffery Munsamy Discipline of Optometry University of KwaZulu-NatalDurban 4000South Africa

●AIM:To assess the influence of near work,time outdoor and parental myopia on the prevalence of myopia in school children in Aba,Nigeria.●METHODS:Primary and secondary school children aged between 8 and 15 y were randomly recruited from 12 schools in Aba.Information on family history,near work and outdoor activity was obtained using myopia risk factor questionnaire.Cycloplegic refraction was performed using autorefraction technique.Myopia was defined as spherical equivalent refraction(SER)≤-0.50 D in the poorer eye.Data were analysed for 1197(male:538 and female:659)children with full relevant data.●RESULTS:Risk of developing myopia was positively associated with parental myopia[odds ratio(OR):6.80;95%CI,2.76-16.74;Poutdoors(OR:0.8;95%CI,0.74-0.87;Poutdoors as this could reduce the prevalence and progression of myopia.

关键词： myopia near work parental myopia outdoor activity school children

A unified 3D space-based navigation model for seamless navigation in indoor and outdoor

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International Journal of Digital Earth 2021年第8期14卷 985-1003页

作者： Jinjin Yan Sisi Zlatanova Abdoulaye Diakité College of Intelligent Systems Science and Engineering Harbin Engineering UniversityHarbinPeople’s Republic of China GRID School of Built EnvironmentFaculty of ArtsDesign and ArchitectureUniversity of New South WalesSydneyAustralia

Seamless navigation has attracted lots of attention and many methods have been reported in the literature or made available as commercial applications.The process of navigation can be interpreted as a continuous movement of 3D objects from one unoccupied 3D indoor/outdoor space to another.From a technical perspective,a 3D navigation model is one of the critical components that should be available to perform successful navigation.A major approach to build a unified navigation model to support seamless path computation is linking indoor navigation networks to outdoor road/street-based networks.Because of different sources of indoor and outdoor navigation networks,the major approach fails to build up true seamless navigation models.With regards to this,we propose a unified 3D space-based navigation model(U3DSNM).The presented model ensures all types of spaces for navigation(indoor,semi-indoor,semi-outdoor,and outdoor)have the same representation,management methods,and network derivation approach,thereby building up unified navigation networks to support seamless navigation paths planning.The model can be linked to the international standards(data models)that are also based on spaces,such as IndoorGML and the on-going version of CityGML 3.0.Three navigation path planning cases show the feasibility of U3DSNM.

关键词： Indoor outdoor 3D space seamless navigation navigation model

Who is at risk in the French mountains? Profiles of the accident victims in outdoor sports and mountain recreation

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Journal of Mountain Science 2017年第8期14卷 1490-1499页

作者： SOULE Bastien REYNIER Véronique LEFEVRE Brice BOUTROY Eric Laboratory of Vulnerabilities & Innovation in Sport University Claude Bernard Lyon 1 Laboratory Sport & Social Environment University Grenoble Alpes

The risk of both severe and frequent injury associated with active pursuits in mountain areas is acknowledged. This phenomenon is all the most relevant to investigate in France that there is a growing enthusiasm for outdoor sports and recreation. This paper focuses on the social-demographic and sporting profiles of accident victims. Our intent is to better understand who is specifically at risk, while practicing mountain recreation, in the French mountains. Such identification doubtlessly constitutes an important asset in order to enhance prevention. Three critical activities are notably tackled, among some others: hiking, a widespread activity that exposes many practitioners to hazardous settings; mountaineering and ski touring, supposedly entailing the most severe injuries.In order to align the information collected, then provide estimations based on the reasoned crossing of these secondary data, we consulted and summarised all the databases that we knew of on the French territory: rescue team intervention reports, aggregated statistics from the sports ministry, sporting federation accident declarations, avalanche experts statistics, mountain guides union accident/incident reports, healthcare facilities admissions, etc. Only the sources consideredto be the most reliable and representative were used, owing to the number of cases processed, the exhaustive nature of data collection, or the level of information detail available. Our method also included consultation of all the parties playing an active role in prevention, training and mountain rescue, thus ensuring a participative, co-constructive approach to the study with the people that have the best knowledge of victim profiles. Around fifty such parties were interviewed on the methods implemented, the benefits and limits of current data, and the main expectations in terms of accidentology progress, thus further enhancing the credibility of the study proposed in this paper. Our results show that the parent population profiles(in terms of age, gender, place of r

关键词： Mountain sports outdoor recreation Accident victims profile

2.5-dimensional angle potential field algorithm for the real-time autonomous navigation of outdoor mobile robots

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Science China(Information Sciences) 2011年第10期54卷 2100-2112页

作者： QIU Quan 1,3 & HAN JianDa 2 1 Beijing Research Center of Intelligent Equipment for Agriculture,Beijing 100097,China 2 State Key Laboratory of Robotics,Shenyang Institute of Automation,Chinese Academy of Sciences,Shenyang 110016,China 3 National Research Center for Intelligent Agricultural Equipment,Beijing 100097,China Beijing Research Center of Intelligent Equipment for Agriculture Beijing China National Research Center for Intelligent Agricultural Equipment Beijing China State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang China

A new real-time algorithm for the autonomous navigation of mobile robots equipped with laser scanners is proposed in this paper.Different from the existing algorithms designed for 2-dimensional navigation problems,the new algorithm introduces the height information of the obstacles into the guidance process and behaves as a 2.5-dimensional angle potential field algorithm (2.5D-APF) to fulfill the navigation requirements under complex outdoor terrain conditions.First,one laser scan is partitioned into two kinds of function sectors: guidance sector and inspecting sector.Then,the guidance sector and the inspecting sectors are reconstructed to form a virtual guidance scan,where the 2.5D information is taken into account.Finally,the conventional APF is improved to analyze the virtual guidance scan and generate the navigation orders.The new algorithm is tested on a tracked mobile robot,and the experimental results validate the proposed algorithm.

关键词： robot 2.5-dimensional outdoor real-time autonomous navigation