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社区化新零售的布局选址与优化发展研究——以南京市盒马鲜生为例 被引量:22
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作者 金安楠 李钢 +3 位作者 王建坡 muhammad sajid MEHMOOD 于悦 林喆 《地理科学进展》 CSSCI CSCD 北大核心 2020年第12期2013-2027,共15页
社区化新零售是新兴的商业模式,也是商业与社区互动的重要场域,值得从城市空间视角深入探究。基于南京市盒马鲜生及相关兴趣点(point of interest,POI)与兴趣面(area of interest,AOI)数据,综合运用空间分析、定量统计、实地调研等方法... 社区化新零售是新兴的商业模式,也是商业与社区互动的重要场域,值得从城市空间视角深入探究。基于南京市盒马鲜生及相关兴趣点(point of interest,POI)与兴趣面(area of interest,AOI)数据,综合运用空间分析、定量统计、实地调研等方法,解析盒马鲜生的服务类型及对象、空间布局特征、区位选址因素,并提出优化发展建议。研究发现:①南京市盒马鲜生服务对象以社区为主,酒店、写字楼为辅;服务客户以具有一定经济基础和消费能力的中青年人群为主。②空间布局总体呈现南—北走向的主城区+近郊区的"5+7三组团"格局,均为"点"状门店+不规则"面"状服务区相结合的"中心—外围"结构,实际配送范围与3 km缓冲区存在差异。③区位选址主要受社区密度和交通环境的影响,对商圈、地价具有依赖性,竞争对手对门店选址影响较小;主要位于社区与道路密度中高值区、商圈边缘地带、主干道两侧及地价中等区域,并利用面状服务区延伸服务范围,获取更多潜在目标客户群。最后从消费群体、运营成本、品牌竞争3个方面探索其区位选址的影响机制,并基于区位选址特征提出优化发展建议。 展开更多
关键词 新零售 盒马鲜生 空间布局 区位选址 南京
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Assessing the Spatial Equality of COVID Testing Sites Maintaining Zero COVID Policy
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作者 muhammad sajid Mehmood Gang Li +3 位作者 Shiyan Zhai Yaochen Qin Annan Jin Lan Li 《Journal of Geographic Information System》 2024年第3期183-200,共18页
Rapid and timely testing is essential to minimize the COVID-19 spread. Decision makers and policy planners need to determine the equal distribution and accessibility of testing sites. This study mainly examines the sp... Rapid and timely testing is essential to minimize the COVID-19 spread. Decision makers and policy planners need to determine the equal distribution and accessibility of testing sites. This study mainly examines the spatial equality of COVID-19 testing sites that maintain a zero COVID policy in Guangzhou City. The study has identified the spatial disparities of COVID testing sites, characteristics of testing locations, and accessibility. The study has obtained information on COVID testing sites in Guangzhou City and population data. Point pattern analyses, Euclidian distance and allocation, and network analyses are the main methods used to achieve the research objectives, and 1183 total COVID testing sites can be recognized in Guangzhou City. Results revealed that spatial disparities could be noticed over the study area. Testing locations of Guangzhou City are highly clustered. The most significant testing sites are located in Haizhu District, which has the third largest population. The highest population density can be identified in Yuexiu District. However, only 94 testing sites are located there. According to all the results, higher disparities can be identified, and a lack of testing sites is located in the north part of the study area. Some people in the northern part have to travel more than 10 km to reach a testing site. Finally, this paper suggests increasing the number of testing sites in the north and south parts of the study area and keeping the same distribution, considering the area, total population, and population density. This kind of research will be helpful to decision-makers in making proper decisions to maintain a zero COVID policy. 展开更多
关键词 COVID-19 Testing Sites Spatial Disparities Spatial Equality Guangzhou City ACCESSIBILITY
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Exploring the Relationship between Spatiotemporal Variations in Air Quality and Meteorological Parameters before and during the COVID-19 Pandemic in Xi’an
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作者 muhammad sajid Mehmood Shiyan Zhai +2 位作者 Gang Li Yaochen Qin Vithana Pathirannehelage Indika Sandamali Wijeratne 《Journal of Geoscience and Environment Protection》 2024年第8期115-148,共34页
The COVID-19 pandemic has significantly changed the air pollution of the world. The present study investigated the temporal and spatial variability in air quality in Xi’an, China, and its relationship with meteorolog... The COVID-19 pandemic has significantly changed the air pollution of the world. The present study investigated the temporal and spatial variability in air quality in Xi’an, China, and its relationship with meteorological parameters during and before the COVID-19 pandemic. The outcomes of this study indicated that air pollutants, PM2.5, NO2, PM10, CO, and SO2 are likely to decrease during winter (25%, 50%, 30%, 40%, and 35%) to spring (30%, 55%, 38%, 50%, and 40%) and summer (40%, 58%, 60%, 55%, and 47%), respectively. However, the concentration of O3-8h increased by 40%, 55%, and 65% during winter, spring, and summer, respectively. The values of the air quality index decreased during the COVID-19 period. Furthermore, significant positive trends were reported in PM2.5, NO2, PM10, O3, and SO2, and no notable trends in CO during the COVID-19 pandemic. Both during and before the COVID-19 period, PM10, NO2, PM2.5, CO, and SO2 showed a negative correlation with the temperature and a moderately positive significant correlation between O3-8h and temperature. The findings of this study would help understand the air pollution circumstances in Xi’an before and during the COVID-19 period and offer helpful information regarding the implications of different air pollution control strategies. 展开更多
关键词 Spatiotemporal Analysis Air Quality Index Meteorological Parameters COVID-19
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青藏高原及其周边寒武纪综合地层、生物群与古地理演化 被引量:1
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作者 孙智新 孙郎 +8 位作者 赵方臣 潘兵 Malik muhammad Saud sajid KHAN Shehryar AHMED 杨传 苗兰云 殷宗军 李国祥 朱茂炎 《中国科学:地球科学》 CSCD 北大核心 2024年第4期968-991,共24页
青藏高原及其周边地区具有漫长且复杂的构造演化历史.印度北部、拉萨、羌塘、柴达木、中祁连等大小不同的克拉通和地块,以及位于它们之间的造山带构成了青藏高原的主体.寒武纪时期,这些克拉通和地块大多位于冈瓦纳大陆的西北缘,并以发... 青藏高原及其周边地区具有漫长且复杂的构造演化历史.印度北部、拉萨、羌塘、柴达木、中祁连等大小不同的克拉通和地块,以及位于它们之间的造山带构成了青藏高原的主体.寒武纪时期,这些克拉通和地块大多位于冈瓦纳大陆的西北缘,并以发育与原特提斯洋有关的复杂岩浆-构造运动而与周边的阿拉伯、中伊朗、阿富汗、塔里木、阿拉善、华北、华南和滇缅马等构造单元相关联.从地层记录上看,这一时期区域内的大部分稳定陆块上发育了由陆源碎屑岩和碳酸盐岩组成的浅水陆棚沉积,其中包含面貌相近的典型浅水相三叶虫组合.而在原特提斯洋中的祁连构造带,寒武系则是一套在大洋扩张环境下形成的、以中基性火山岩和硅质岩为主的复杂地层序列,其中包含的碳酸盐岩含有斜坡相三叶虫组合.本文在广泛文献调研的基础上,结合第二次青藏高原综合科学考察中的野外观察及新获得的化石证据,对青藏高原及其周边地区不同构造单元上寒武纪地层发育的总体特征进行了概述.在此基础上,利用可获得的生物地层学和同位素年代学等资料,总结了不同构造单元上寒武纪地层的划分和年代地层对比,编制了岩石和生物地层的综合对比表.此外,从生物古地理的角度,简要讨论了寒武纪研究区内主要构造单元的古地理相关性,以及与原特提斯构造带演变有关的问题. 展开更多
关键词 青藏高原 寒武系 地层 古地理 生物群 冈瓦纳大陆 原特提斯洋
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青藏高原及其周边成冰纪-埃迪卡拉纪综合地层、生物群与古地理演化 被引量:1
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作者 孙郎 Malik muhammad Saud sajid KHAN +13 位作者 杨传 孙智新 潘兵 Shehryar AHMED 苗兰云 孙玮辰 胡春林 孙晓娟 罗翠 陈波 殷宗军 赵方臣 李国祥 朱茂炎 《中国科学:地球科学》 CSCD 北大核心 2024年第4期936-967,共32页
青藏高原及其周边的块体,包括印度板块、拉萨地块、羌塘地块、塔里木板块、欧龙布鲁克地块、中祁连地块、阿拉善地块、华北板块、扬子板块、中伊朗地块和阿曼等,以及各块体之间造山带的复杂演化历史是地球科学研究的前沿和热点.成冰系... 青藏高原及其周边的块体,包括印度板块、拉萨地块、羌塘地块、塔里木板块、欧龙布鲁克地块、中祁连地块、阿拉善地块、华北板块、扬子板块、中伊朗地块和阿曼等,以及各块体之间造山带的复杂演化历史是地球科学研究的前沿和热点.成冰系和埃迪卡拉系广泛分布于该地区的各个构造单元,其中阿曼、印度板块、扬子板块以及塔里木板块发育有相对完整的成冰系和埃迪卡拉系;而在中伊朗地块、南羌塘地块、中祁连地块、阿拉善地块及华北板块,目前已知仅有埃迪卡拉系发育.基于前人对青藏高原及其周边地区成冰系和埃迪卡拉系的研究,结合第二次青藏高原综合科学考察研究项目开展以来获得的新资料和研究进展,本文建立了该地区成冰系和埃迪卡拉系代表性地层序列对比表.在此基础上,本文梳理了该地区这一时期生物群和重大地质事件的研究现状和存在的问题.结果表明,该地区各板块埃迪卡拉纪化石的保存和组合面貌各具特色,但普遍发现有典型埃迪卡拉纪末期化石分子Cloudina和Shaanxilithes;除成冰纪两次全球性冰期事件外,在青藏高原北缘各块体(华北板块、阿拉善地块、北祁连构造带、中祁连地块、欧龙布鲁克地块、塔里木板块)以及伊朗中南部普遍记录了一次埃迪卡拉纪晚期的冰川事件,但该事件的时限、分布范围和成因有待进一步揭示;同时,埃迪卡拉纪中期DOUNCE/Shruam碳同位素负异常事件在青藏高原周边地区也具有广泛记录.综合现有研究资料发现,在成冰纪-埃迪卡拉纪期间,青藏高原及其周边地区大多数块体从罗迪尼亚超大陆裂解出来后,可能通过泛非运动构成东冈瓦纳大陆的一部分,而部分板块(如华北板块)位于冈瓦纳大陆和劳伦大陆之间.总体而言,该地区的主要块体在成冰纪-埃迪卡拉纪期间具体的古地理演化模型存在较多争议,亟需� 展开更多
关键词 青藏高原 成冰系 埃迪卡拉系 地层 古地理 生物群 冈瓦纳大陆
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