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Evaluation of urban underground space resources using a negative list method: Taking Xi'an City as an example in China 被引量:7
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作者 Mao-sheng Zhang Hua-qi Wang +3 位作者 Ying Dong Lin Li Ping-ping Sun Ge Zhang 《China Geology》 2020年第1期124-136,共13页
Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city env... Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city environment,build livable city and increase the capacity of the city.Based on the analysis of existing evaluation methods and their problems,a method for evaluating underground space resources based on a negative list of adverse factors affecting underground space development is proposed,to be primarily used in urban planning stages.A list of the adverse factors is established,including limiting factors,constraining factors and influencing factors.Taking Xi'an as an example,using a geographical information system platform,a negative list of adverse factors for the underground space resources in Xi'an City are evaluated,and preventive measures are proposed.Natural resources,exploitable resources,and the potential growth of exploitable underground space resources are evaluated.Underground space assessment in the different development stages of the city,collaborative utilization and safety evaluation for multiple subsurface resources,environmental impact and assessment,as well as evaluation methods based on big data and intelligent optimization algorithms are all discussed with the aim of serving city planning and construction. 展开更多
关键词 Urban geology Negative list Natural resources for underground space Exploitable resources for underground space 3D geological structure model GIS platform Urban geological survey engineering xi'an city Shaanxi Province China
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Dynamic Analysis of Coupling Relationship between Economic Development and Ecological Environment Based on Entropy Method——A Case Study of Xi'an City 被引量:1
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作者 YU Feng-ming DU Zhong-chao ZHOU Du-hui 《Meteorological and Environmental Research》 CAS 2011年第9期62-66,76,共6页
[Objective] The aim was to study the coupling relationship between economic development and ecological environment. [Method] Firstly, the evaluation index system for the coupling system of economic development and eco... [Objective] The aim was to study the coupling relationship between economic development and ecological environment. [Method] Firstly, the evaluation index system for the coupling system of economic development and ecological environment in Xi’an City was established, then the dynamic variation of coupling relationship between economic development and ecological environment in Xi’an City from 2001 to 2010 was analyzed by using entropy method, finally some corresponding suggestions were put forward according to the problems in the current development model. [Result] The economic development and ecological environment of Xi’an have made a significant upgrading and improvement from 2001 to 2010, namely showing a stable upward trend on the whole, and were in a well-coordinated development state in 2010. However, the development level of ecological environment obviously lagged behind economic development level. In addition, there were obvious differences in the development rate of sub-systems, that is, economic efficiency and economic level developed rapidly, while the carrying capacity of ecological environment and economic vitality grew slowly and unstably. [Conclusion] The research could provide theoretical bases for the establishment of strategies for the coordinated development economy and environment in Xi’an City. 展开更多
关键词 Entropy method Economic development Ecological environment xi'an city China
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Climate Characteristics of High Temperature Weather in Xi'an City in Recent 59 Years
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作者 MENG Xiao-rong YANG Xiao-chun +1 位作者 Qu Jing JIN Li-na 《Meteorological and Environmental Research》 CAS 2011年第9期43-46,共4页
[Objective] The aim was to study the characteristics of high temperature in Xi’an City over the last 59 years. [Method] By dint of daily highest temperature in the Xi’an observatory, the climate characteristics of h... [Objective] The aim was to study the characteristics of high temperature in Xi’an City over the last 59 years. [Method] By dint of daily highest temperature in the Xi’an observatory, the climate characteristics of high temperature at different intensities and the high attitude circulation were studied by statistical method. [Result] Over the last 59 years, there were 22.95 high temperature days each year on average in Xi’an City, which occurred from the last ten days of April to the first ten days of September. Most high temperature days occurred in the last ten days of July, followed by that in the last ten days of June. There were two peak values in the last ten days of June and last ten days of July when temperature ≥38.0 ℃. For the hottest day, it occurred most in the last twenty days of June, followed by July, and rarely in August. The interannual changes in the high temperature day, hot day and hottest day showed one-little and one-much trend. It was much from 1950s to 1960s, from 1970s to 1980s and then grew more after 1990s. The annual extreme highest temperature took place in the last twenty days of June, and then in the last ten days of July. Its interannual changes showed high-low-high trend. The high temperature appeared most often in July and also lasted for the longest duration. The hot day lasted for two days. The hottest days of ≥40.0 ℃ were very rare. The circulation of high temperature generally fell into one of four categories: continental high pressure controlling type, subtropical high controlling type, strip high pressure controlling type and northwest airstream controlling type. [Conclusion] The study provided references for the forecast and pre-warning of high temperature. 展开更多
关键词 High temperature Changes characteristics Circulation characteristics xi'an city China
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Family Planning Management Of the Floating Population in Xi'an City
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《China Population Today》 1996年第Z1期29-29,共1页
FamilyPlanningManagementOftheFloatingPopulationinXi'anCity¥//Urbanfamilyplanningmanagementunitsareassignedto... FamilyPlanningManagementOftheFloatingPopulationinXi'anCity¥//Urbanfamilyplanningmanagementunitsareassignedtoperformsuchduties... 展开更多
关键词 Family Planning Management Of the Floating Population in Xi’an city
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The retrospect and prospect on environmental legal system research of Xi'an City
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作者 Chen Min Zhang Xiaoling 《Engineering Sciences》 EI 2012年第4期76-82,共7页
Xi'an City is an important city of western region, facing the mission of constructing international metropolitan. There are many environmental issues in the city, which should be solved by legal construction. Base... Xi'an City is an important city of western region, facing the mission of constructing international metropolitan. There are many environmental issues in the city, which should be solved by legal construction. Based on the environmental status of the city, the construction content of environmental legal system was analyzed, focusing on conflict resolution, and the corresponding ways of research were proposed. 展开更多
关键词 环境法律制度 城市 西安 环境法制建设 展望 国际大都会 西部地区 环境问题
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Current Situations and Development Recommendations for Pomegranate Industry in Lintong District of Xi'an City
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作者 Jianbin YANG 《Asian Agricultural Research》 2018年第9期19-22,共4页
Lintong pomegranate is well known in China and ranks first among the top five famous pomegranate types in China. In 2006,it obtained the national geographical indication protection product certification. In recent yea... Lintong pomegranate is well known in China and ranks first among the top five famous pomegranate types in China. In 2006,it obtained the national geographical indication protection product certification. In recent years,the pomegranate industry of Lintong has developed rapidly,but there are also some problems,which have become the weak points of local economic development. In order to promote the further sustainable development of the Lintong pomegranate industry,on the basis of the questionnaire survey,the paper introduced the role of Lintong pomegranate in the county economy,resource advantages,planting and marketing,the low scientific and technological content,shrinkage of planting area,decline of brand influence of Lintong pomegranate,lack of awareness of industrialization of characteristic agriculture,single product type,short industrial chain,etc. Finally,it came up with pertinent recommendations on the basis of these problems. In order to develop pomegranate,Lintong District should make full use of the local advantages,broaden the marketing channels,rationally apply the theory of industrialization,improve the cooperative organization,and form the characteristic industrial chain of Lintong pomegranate. 展开更多
关键词 石榴产业 发展现状 农业 经营策略
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文旅融合:“Citywalk”热潮下的冷思考
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作者 赵欣 《河北旅游职业学院学报》 2024年第1期60-64,共5页
“Citywalk”(城市漫步)强调慢节奏和沉浸式体验,是深受年轻人追捧的文旅消费新范式。“Citywalk”火爆出圈的背后,也存在着产品辨识度不高、利润低、专业性不强、产品更迭慢等问题。“文旅融合”的有效健康发展,需要在资源供给、产品... “Citywalk”(城市漫步)强调慢节奏和沉浸式体验,是深受年轻人追捧的文旅消费新范式。“Citywalk”火爆出圈的背后,也存在着产品辨识度不高、利润低、专业性不强、产品更迭慢等问题。“文旅融合”的有效健康发展,需要在资源供给、产品创新、服务品质等方面开展全方位、多领域的合作联动,成果共享才能形成互利共赢新格局。 展开更多
关键词 文旅融合 休闲游 城市旅游
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物质循环视角下的“可持续漂浮城市”解析——以BIG事务所“Oceanix City”方案为例
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作者 樊东奇 刘长安 《中外建筑》 2024年第4期64-69,共6页
随着时代发展,现代城市正面临着土地短缺、住房紧张、能源枯竭以及海平面上升等一系列问题。因而探索陆地之外的生存空间,进而缓解多种城市问题是人们长久以来的愿景。近年来,联合国人居署提出可持续发展的漂浮城市概念,并由BIG事务所... 随着时代发展,现代城市正面临着土地短缺、住房紧张、能源枯竭以及海平面上升等一系列问题。因而探索陆地之外的生存空间,进而缓解多种城市问题是人们长久以来的愿景。近年来,联合国人居署提出可持续发展的漂浮城市概念,并由BIG事务所设计了世界上第一个弹性化和可持续的漂浮城市原型——Oceanix City。该城市通过引入城市农业,配置能量、水分、养分等循环系统实现最大限度自给自足,满足居民日常生活需求,达到可持续发展的目标。文章运用文献研究法梳理了从漂浮建筑、漂浮社区到漂浮城市的发展历程,并以“Oceanix City”方案为案例分析对象,从物质循环视角入手解析方案的规划设计与建造、循环系统的运作等方面,总结得出拓展海上空间、引入城市农业并构建物质循环系统是应对上述城市问题的有效方式,以期为未来城市的可持续发展提供启示。 展开更多
关键词 漂浮城市 “Oceanix city”方案 物质循环 可持续发展 城市农业
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Development of a Lightweight Model for Handwritten Dataset Recognition: Bangladeshi City Names in Bangla Script
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作者 MdMahbubur Rahman Tusher Fahmid Al Farid +6 位作者 MdAl-Hasan Abu Saleh Musa Miah Susmita Roy Rinky Mehedi Hasan Jim Sarina Mansor MdAbdur Rahim Hezerul Abdul Karim 《Computers, Materials & Continua》 SCIE EI 2024年第8期2633-2656,共24页
The context of recognizing handwritten city names,this research addresses the challenges posed by the manual inscription of Bangladeshi city names in the Bangla script.In today’s technology-driven era,where precise t... The context of recognizing handwritten city names,this research addresses the challenges posed by the manual inscription of Bangladeshi city names in the Bangla script.In today’s technology-driven era,where precise tools for reading handwritten text are essential,this study focuses on leveraging deep learning to understand the intricacies of Bangla handwriting.The existing dearth of dedicated datasets has impeded the progress of Bangla handwritten city name recognition systems,particularly in critical areas such as postal automation and document processing.Notably,no prior research has specifically targeted the unique needs of Bangla handwritten city name recognition.To bridge this gap,the study collects real-world images from diverse sources to construct a comprehensive dataset for Bangla Hand Written City name recognition.The emphasis on practical data for system training enhances accuracy.The research further conducts a comparative analysis,pitting state-of-the-art(SOTA)deep learning models,including EfficientNetB0,VGG16,ResNet50,DenseNet201,InceptionV3,and Xception,against a custom Convolutional Neural Networks(CNN)model named“Our CNN.”The results showcase the superior performance of“Our CNN,”with a test accuracy of 99.97% and an outstanding F1 score of 99.95%.These metrics underscore its potential for automating city name recognition,particularly in postal services.The study concludes by highlighting the significance of meticulous dataset curation and the promising outlook for custom CNN architectures.It encourages future research avenues,including dataset expansion,algorithm refinement,exploration of recurrent neural networks and attention mechanisms,real-world deployment of models,and extension to other regional languages and scripts.These recommendations offer exciting possibilities for advancing the field of handwritten recognition technology and hold practical implications for enhancing global postal services. 展开更多
关键词 Handwritten recognition Bangladeshi city names Bangla handwritten city name automated postal services
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Grid System Analysis of Urban Flora of Bukhara City (Uzbekistan)
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作者 Abdulla M. Umedov Husniddin K. Esanov 《American Journal of Plant Sciences》 CAS 2024年第2期139-144,共6页
This article presents information on the study of the flora of Uzbekistan based on grid system mapping. The urban flora of the city of Bukhara was researched in it. As a result of research, the territory of Bukhara ci... This article presents information on the study of the flora of Uzbekistan based on grid system mapping. The urban flora of the city of Bukhara was researched in it. As a result of research, the territory of Bukhara city was divided into 85 indexes based on 1 × 1 km<sup>2</sup> grid mapping system. The diversity and density of species in the indexes are determined. The influence of anthropogenic factors on the diversity of species in the indexes is determined. 展开更多
关键词 Bukhara city Urban Flora INDEX Grid Map System HERBARIUM Geoinformation
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Geospatial Technology Integration in Smart City Frameworks for Achieving Climate Neutrality by 2050: A Case Study of Limassol Municipality, Cyprus
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作者 Antonis Papantoniou Chris Danezis Diofantos Hadjimitsis 《Journal of Geographic Information System》 2024年第1期44-60,共17页
This study investigated the integration of geospatial technologies within smart city frameworks to achieve the European Union’s climate neutrality goals by 2050. Focusing on rapid urbanization and escalating climate ... This study investigated the integration of geospatial technologies within smart city frameworks to achieve the European Union’s climate neutrality goals by 2050. Focusing on rapid urbanization and escalating climate challenges, the research analyzed how smart city frameworks, aligned with climate neutrality objectives, leverage geospatial technologies for urban planning and climate action. The study included case studies from three leading European cities, extracting lessons and best practices in implementing Climate City Contracts across sectors like energy, transport, and waste management. These insights highlighted the essential role of EU and national authorities in providing technical, regulatory, and financial support. Additionally, the paper presented the application of a WEBGIS platform in Limassol Municipality, Cyprus, demonstrating citizen engagement and acceptance of the proposed geospatial framework. Concluding with recommendations for future research, the study contributed significant insights into the advancement of urban sustainability and the effectiveness of geospatial technologies in smart city initiatives for combating climate change. 展开更多
关键词 Smart Cities Geospatial Technologies Smart city Frameworks Geospatial Integration
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An Enhanced Multiview Transformer for Population Density Estimation Using Cellular Mobility Data in Smart City
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作者 Yu Zhou Bosong Lin +1 位作者 Siqi Hu Dandan Yu 《Computers, Materials & Continua》 SCIE EI 2024年第4期161-182,共22页
This paper addresses the problem of predicting population density leveraging cellular station data.As wireless communication devices are commonly used,cellular station data has become integral for estimating populatio... This paper addresses the problem of predicting population density leveraging cellular station data.As wireless communication devices are commonly used,cellular station data has become integral for estimating population figures and studying their movement,thereby implying significant contributions to urban planning.However,existing research grapples with issues pertinent to preprocessing base station data and the modeling of population prediction.To address this,we propose methodologies for preprocessing cellular station data to eliminate any irregular or redundant data.The preprocessing reveals a distinct cyclical characteristic and high-frequency variation in population shift.Further,we devise a multi-view enhancement model grounded on the Transformer(MVformer),targeting the improvement of the accuracy of extended time-series population predictions.Comparative experiments,conducted on the above-mentioned population dataset using four alternate Transformer-based models,indicate that our proposedMVformer model enhances prediction accuracy by approximately 30%for both univariate and multivariate time-series prediction assignments.The performance of this model in tasks pertaining to population prediction exhibits commendable results. 展开更多
关键词 Population density estimation smart city TRANSFORMER multiview learning
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An Analysis of the Lifestyle and Mental Health Status of Adult People Living in Dhaka City: A Cross-Sectional Study in Post COVID-19 Era
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作者 Tania Ahmed Chowdhury Nasrin Akhter +3 位作者 Ishrat Hossain Rezwana Jahan Pallabi Sultana Mohammad Jahangir Alam 《Advances in Infectious Diseases》 CAS 2024年第2期393-410,共18页
Introduction: The Novel Coronavirus or COVID-19 affected all the megacities of the world and made the mental health and lifestyle of people paralyzed. According to different studies, such difficulties were different i... Introduction: The Novel Coronavirus or COVID-19 affected all the megacities of the world and made the mental health and lifestyle of people paralyzed. According to different studies, such difficulties were different in scale in different cities depending on the demographic attributes of the people. This phenomenon has created the essence of the current study to examine the health conditions in terms of their mental health, lifestyle, and demographic attributes during and immediate past of the COVID-19 era. Method: It was a cross-sectional study covering the people of Dhaka City Corporation. For this purpose, a multistage sampling method was applied, under which the respondents were selected randomly and a self-administered structured questionnaire was used to collect data. The questionnaire was developed based on the DASS 21, as it was suitable to measure the components of mental health in the form of depression, anxiety, and stress. Descriptive analysis and cross-tabulation were applied to find out the association between dependent and independent variables, whereas, a chi-square test was performed to examine the hypothesis. Finally, multivariate analysis was done to find out the risk factors. Three logistic regression models were developed for three dependent variables. Result: The findings of the analysis revealed that the lifestyle of people had severely influenced the components of their mental health conditions during and immediate past of COVID-19 in the Dhaka City Corporation, which varies to some extent depending on the demographic attributes of those. Conclusion: The above findings are statistically significant enough to conclude about the essence of taking preventive measures regarding mental health issues in the future. However, the limitations of this study-keeping it within the urban areas and the educated people, have also created the venue for future researchers to move with their research endeavors in the rural areas nationwide and thus generalize the results. 展开更多
关键词 LIFESTYLE Mental Health DEPRESSION Stress ANXIETY Dhaka city DASS 21 COVID-19
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Assessment of Breast Cancer Prevention Practices among Women Attending Primary Health Care in Abha City, Aseer Region, Saudi Arabia
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作者 Sabah Mohammed Asiri Sultan Yahia Alfifii +6 位作者 Tagreed Khairan Al-Rashidi Sager Misfer Alqahtani Faiz Abdulrahman Alshafa Fayez Mari Alamri Amal Mohammed Asiri Fatima Mohammed Ali Almagadi Thuraya Mohammed Asiri 《International Journal of Clinical Medicine》 CAS 2024年第2期31-54,共24页
Cancer is a leading cause of death worldwide, with breast cancer being the most common (2.26 million new cases and 685,000 deaths). In Saudi Arabia, breast cancer ranked the first among females in 2014, accounting for... Cancer is a leading cause of death worldwide, with breast cancer being the most common (2.26 million new cases and 685,000 deaths). In Saudi Arabia, breast cancer ranked the first among females in 2014, accounting for 15.9% of all cancers reported among Saudi nationals and 28.7% of all cancers reported among females of all ages. Early detection of breast cancer could decrease the risks, have a better prognosis, and have better outcomes/more successful treatments. Prevalence of breast cancer reached more than 25% of all diagnosed cancer in the kingdom among women. Aim: This study aims to assess the knowledge and performance of women attending primary care centers about breast self-examination and mammogram screening for prevention and early detection of breast cancer in Abha city primary healthcare centers, Kingdom of Saudi Arabia. Research Method: cross sectional design was conducted by using questionnaire, which was distributed to primary care center nurses. The collected data was statistically analyzed using the Statistical Package for Social Sciences, version 25. Results: The study found that participants had poor awareness and knowledge about breast self-examination, risk factors for breast cancer, and trends and practices in early diagnosis of breast cancer. Conclusion and Recommendations: It recommends increasing awareness campaigns and providing educational programs to improve knowledge and practices. 展开更多
关键词 ASSESSMENT Breast Cancer Prevention Practices Women Attending Health Care Centers Abha city
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The Contribution of AI-Powered Mobile Apps to Smart City Ecosystems
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作者 Zaki Ali Bayashot 《Journal of Software Engineering and Applications》 2024年第3期143-154,共12页
In the groundbreaking study “The Contribution of AI-powered Mobile Apps to Smart City Ecosystems,” authored by Zaki Ali Bayashot, the transformative role of artificial intelligence (AI) in urban development is metic... In the groundbreaking study “The Contribution of AI-powered Mobile Apps to Smart City Ecosystems,” authored by Zaki Ali Bayashot, the transformative role of artificial intelligence (AI) in urban development is meticulously examined. This comprehensive research delineates the multifaceted ways in which AI-powered mobile applications can significantly enhance the efficiency, sustainability, and livability of urban environments, marking a pivotal step towards the realization of smart cities globally. Bayashot meticulously outlines the critical areas where AI-powered apps offer unprecedented advantages, including urban mobility, public safety, energy management, and environmental monitoring. By leveraging AI’s capabilities, these applications not only streamline city operations but also foster a more sustainable interaction between city dwellers and their environment. The paper emphasizes the importance of data-driven decision-making in urban planning, showcasing how AI analytics can predict and mitigate traffic congestion, optimize energy consumption, and enhance emergency response strategies. The author also explores the social implications of AI in urban settings, highlighting the potential for these technologies to bridge the gap between government entities and citizens. Through engaging case studies, Bayashot demonstrates how participatory governance models, enabled by AI apps, can promote transparency, accountability, and citizen engagement in urban management. A significant contribution of this research is its focus on the challenges and opportunities presented by the integration of AI into smart city ecosystems. Bayashot discusses the technical, ethical, and privacy concerns associated with AI applications, advocating for a balanced approach that ensures technological advancements do not come at the expense of civil liberties. The study calls for robust regulatory frameworks to govern the use of AI in public spaces, emphasizing the need for ethical AI practices that respect privacy and promote inclusivity. Furthermore, Bayashot’s research underscores the necessity of cross-disciplinary collaboration in the development and implementation of AI technologies in urban contexts. By bringing together experts from information technology, urban planning, environmental science, and social sciences, the author argues for a holistic approach to smart city development. This interdisciplinary strategy ensures that AI applications are not only technologically sound but also socially and environmentally responsible. The paper concludes with a visionary outlook on the future of smart cities, posited on the seamless integration of AI technologies. Bayashot envisions a world where AI-powered mobile apps not only facilitate smoother urban operations but also empower citizens to actively participate in the shaping of their urban environments. This research serves as a critical call to action for policymakers, technologists, and urban planners to embrace AI as a tool for creating more sustainable, efficient, and inclusive cities. By presenting a detailed analysis of the current state of AI in urban development, coupled with practical insights and forward-looking recommendations, “The Contribution of AI-powered Mobile Apps to Smart City Ecosystems” stands as a seminal work that is poised to inspire and guide the evolution of urban landscapes worldwide. Its comprehensive exploration of the subject matter, combined with its impactful conclusions, make it a must-read for anyone involved in the field of smart city development, AI technology, or urban policy-making. 展开更多
关键词 Mobile Applications Smart Cities Artificial Intelligence IOT
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Resilience assessment and optimization method of city road network in the post-earthquake emergency period
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作者 Wang Haoran Xiao Jia +1 位作者 Li Shuang Zhai Changhai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期765-779,共15页
The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social order.To improve the seismic resilience of city road networks,a resilience ... The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social order.To improve the seismic resilience of city road networks,a resilience evaluation method used in the post-earthquake emergency period is proposed.The road seismic damage index of a city road network can consider the influence of roads,bridges and buildings along the roads,etc.on road capacity after an earthquake.A function index for a city road network is developed,which reflects the connectivity,redundancy,traffic demand and traffic function of the network.An optimization model for improving the road repair order in the post-earthquake emergency period is also developed according to the resilience evaluation,to enable decision support for city emergency management and achieve the best seismic resilience of the city road network.The optimization model is applied to a city road network and the results illustrate the feasibility of the resilience evaluation and optimization method for a city road network in the post-earthquake emergency period. 展开更多
关键词 city road network post-earthquake emergency period traffic demand resilience evaluation optimization model
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Some of the Chemical and Physical Characteristics of the Graff River in Kut City, Iraq
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作者 Salih Mahdi Ali Imad Kazem Ali 《Open Journal of Modern Hydrology》 CAS 2024年第1期56-67,共12页
Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period fro... Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period from October/2018 to March/2019, Seven variables of river water have been analyzed: temperature PH, electrical conductivity, TDS, turbidity, alkaline, and chloride. The results showed that most of the chemical and physical water properties of the river were in normal proportions and did not rise, except for the turbidity, which was at a very high level, and that the pH values were close to the basal side. The results of the statistical analysis revealed positive significant relationships between the pH and (chloride and TDS). On the other hand, between electrical conductivity and both previous variables as well. And a negative significant connection between temperature and alkaline. 展开更多
关键词 Graff River Kut city Iraq Chemical Characteristics Physical Characteristics
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Planning and construction of Xiong’an New Area(city of over 5 million people):Contributions of China’s geologists and urban geology
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作者 Bo Han Zhen Ma +9 位作者 Liang-jun Lin Hong-wei Liu Yi-hang Gao Yu-bo Xia Hai-tao Li Xu Guo Feng Ma Yu-shan Wang Ya-long Zhou Hong-qiang Li 《China Geology》 CAS CSCD 2024年第3期382-408,共27页
China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and t... China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and to expedite the coordinated development of the Beijing-Tianjin-Hebei region.From 2017 to 2021,the China Geological Survey(CGS)took the lead in multi-factor urban geological surveys involving space,resources,environments,and disasters according to the general requirements of“global vision,international standards,distinctive Chinese features,and future-oriented goals”in Xiong’an New Area,identifying the engineering geologic conditions and geologic environmental challenges of this area.The achievements also include a 3D engineering geological structure model for the whole area,along with“one city proper and five clusters”,insights into the ecology and the background endowment of natural resources like land,geothermal resources,groundwater,and wetland of the area before engineering construction,a comprehensive monitoring network of resources and environments in the area,and the“Transparent Xiong’an”geological information platform that is open,shared,dynamically updated,and three-dimensionally visualized.China’s geologists and urban geology have played a significant role in the urban planning and construction of Xiong’an New Area,providing whole-process geological solutions for urban planning,construction,operation and management.The future urban construction of Xiong’an New Area will necessitate the theoretical and technical support of earth system science(ESS)from various aspects,and the purpose is to enhance the resilience of the new type of city and to provide support for the green,low-carbon,and sustainable development of this area. 展开更多
关键词 Low Carbon New city Planning and construction Land Geothermal resources Groundwater Wetland Underground space Geologic disasters Site stability Natural resource Ecosystem Geological safety Transparent Xiong’an Resilient city Xiong’an New Area
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Subsurface multi-physical characterization of mountain excavation and city construction in loess plateau with a fiber-optic sensing system
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作者 Jie Liu Bin Shi +3 位作者 Kai Gu Meng-Ya Sun Jun-Cheng Yao He-Ming Han 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2935-2946,共12页
Mountain excavation and city construction(MECC)projects being launched in the Loess Plateau in China involve the creation of large-scale artificial land.Understanding the subsurface evolution characteristics of the ar... Mountain excavation and city construction(MECC)projects being launched in the Loess Plateau in China involve the creation of large-scale artificial land.Understanding the subsurface evolution characteristics of the artificial land is essential,yet challenging.Here,we use an improved fiber-optic monitoring system for its subsurface multi-physical characterization.The system enables us to gather spatiotemporal distribution of various parameters,including strata deformation,temperature,and moisture.Yan’an New District was selected as a case study to conduct refined in-situ monitoring through a 77 m-deep borehole and a 30 m-long trench.Findings reveal that the ground settlement involves both the deformation of the filling loess and the underlying intact loess.Notably,the filling loess exhibits a stronger creep capability compared to underlying intact loess.The deformation along the profile is unevenly distributed,with a positive correlation with soil moisture.Water accumulation has been observed at the interface between the filling loess and the underlying intact loess,leading to a significant deformation.Moreover,the temperature and moisture in the filling loess have reached a new equilibrium state,with their depths influenced by atmospheric conditions measuring at 31 m and 26 m,respectively.The refined investigation allows us to identify critical layers that matter the sustainable development of newly created urban areas,and provide improved insights into the evolution mechanisms of land creation. 展开更多
关键词 Mountain excavation and city construction Fiber-optic monitoring Multi-physical characterization Compacted loess
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Bivariate Analysis of Pollutants Monthly Maxima in Mexico City Using Extreme Value Distributions and Copula
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作者 Juan A. Vazquez-Morales Eliane R. Rodrigues Hortensia J. Reyes-Cervantes 《Journal of Environmental Protection》 2024年第7期796-826,共31页
In the present work, we are interested in studying the joint distributions of pairs of the monthly maxima of the pollutants used by the environmental authorities in Mexico City to classify the air quality in the metro... In the present work, we are interested in studying the joint distributions of pairs of the monthly maxima of the pollutants used by the environmental authorities in Mexico City to classify the air quality in the metropolitan area. In order to obtain the joint distributions a copula will be considered. Since we are analyzing the monthly maxima, the extreme value distributions of Weibull and Fréchet are taken into account. Using these two distributions as marginal distributions in the copula a Bayesian inference was made in order to estimate the parameters of both distributions and also the association parameters appearing in the copula model. The pollutants taken into account are ozone, nitrogen dioxide, sulphur dioxide, carbon monoxide, and particulate matter with diameters smaller than 10 and 2.5 microns obtained from the Mexico City monitoring network. The estimation was performed by taking samples of the parameters generated through a Markov chain Monte Carlo algorithm implemented using the software OpenBugs. Once the algorithm is implemented it is applied to the pairs of pollutants where one of the coordinates of the pair is ozone and the other varies on the set of the remaining pollutants. Depending on the pollutant and the region where they were collected, different results were obtained. Hence, in some cases we have that the best model is that where we have a Fréchet distribution as the marginal distribution for the measurements of both pollutants and in others the most suitable model is the one assuming a Fréchet for ozone and a Weibull for the other pollutant. Results show that, in the present case, the estimated association parameter is a good representation to the correlation parameters between the pair of pollutants analyzed. Additionally, it is a straightforward task to obtain these correlation parameters from the corresponding association parameters. 展开更多
关键词 COPULA Extreme Value Distribution Bayesian Inference Air Pollution Mexico city
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