An Enhanced Multiview Transformer for Population Density Estimation Using Cellular Mobility Data in Smart City

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.

Do companies influenced by smart cities pay more attention to green governance?Mechanism and optimal spatial correlation

Smart cities are a way for China to construct an innovative and environmentally conscious nation.The paper examines the impact of smart cities on corporate green governance and provides a theoretical foundation for formulating and executing smart city policy in China.Based on panel data from Chinese A-share listed companies in Shanghai and Shenzhen from 2008 to 2020,this study constructs a multiperiod double-difference model to examine the influence of smart cities on corporate green governance.Additionally,it uses a spatial double-difference model to investigate the spatial spillover effect of smart cities on neighboring areas.The findings indicate that smart cities effectively enhance corporate green governance.Analyzing the influencing mechanisms reveals that resource allocation efficiency,technological innovation,management environmental awareness,and regional environmental enforcement efforts act as mediators.Furthermore,the study reveals that the impact of smart cities on promoting corporate green governance is more pronounced in regions with lower levels of marketization and resource-based cities.Moreover,the research explores the spatial spillover effects of smart cities,with an effective radius of approximately 350 km.The optimal spatial correlation zone for green governance of businesses in neighboring areas in relation to smart cities is within a range of 250-350 km.This is manifested by the significant promotion of green governance in neighboring area businesses facilitated by smart cities.

Factors Influencing the Spatial Variability of Air Temperature Urban Heat Island Intensity in Chinese Cities

Few studies have investigated the spatial patterns of the air temperature urban heat island(AUHI)and its controlling factors.In this study,the data generated by an urban climate model were used to investigate the spatial variations of the AUHI across China and the underlying climate and ecological drivers.A total of 355 urban clusters were used.We performed an attribution analysis of the AUHI to elucidate the mechanisms underlying its formation.The results show that the midday AUHI is negatively correlated with climate wetness(humid:0.34 K;semi-humid:0.50 K;semi-arid:0.73 K).The annual mean midnight AUHI does not show discernible spatial patterns,but is generally stronger than the midday AUHI.The urban–rural difference in convection efficiency is the largest contributor to the midday AUHI in the humid(0.32±0.09 K)and the semi-arid(0.36±0.11 K)climate zones.The release of anthropogenic heat from urban land is the dominant contributor to the midnight AUHI in all three climate zones.The rural vegetation density is the most important driver of the daytime and nighttime AUHI spatial variations.A spatial covariance analysis revealed that this vegetation influence is manifested mainly through its regulation of heat storage in rural land.

Bivariate Analysis of Pollutants Monthly Maxima in Mexico City Using Extreme Value Distributions and Copula

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.

Ensemble Deep Learning Based Air Pollution Prediction for Sustainable Smart Cities

Big data and information and communication technologies can be important to the effectiveness of smart cities.Based on the maximal attention on smart city sustainability,developing data-driven smart cities is newly obtained attention as a vital technology for addressing sustainability problems.Real-time monitoring of pollution allows local authorities to analyze the present traffic condition of cities and make decisions.Relating to air pollution occurs a main environmental problem in smart city environments.The effect of the deep learning(DL)approach quickly increased and penetrated almost every domain,comprising air pollution forecast.Therefore,this article develops a new Coot Optimization Algorithm with an Ensemble Deep Learning based Air Pollution Prediction(COAEDL-APP)system for Sustainable Smart Cities.The projected COAEDL-APP algorithm accurately forecasts the presence of air quality in the sustainable smart city environment.To achieve this,the COAEDL-APP technique initially performs a linear scaling normalization(LSN)approach to pre-process the input data.For air quality prediction,an ensemble of three DL models has been involved,namely autoencoder(AE),long short-term memory(LSTM),and deep belief network(DBN).Furthermore,the COA-based hyperparameter tuning procedure can be designed to adjust the hyperparameter values of the DL models.The simulation outcome of the COAEDL-APP algorithm was tested on the air quality database,and the outcomes stated the improved performance of the COAEDL-APP algorithm over other existing systems with maximum accuracy of 98.34%.

Investigation and Analysis of Main Diseases of Landscape Plants in the Main Urban Area of Lu'an City

To figure out the disease occurrence of landscape plants in the main urban area of Lu'an City,the author investigated the disease occurrence of landscape plants in park green space,residential green space,unit attached green space and main road in the area under administration.The survey results showed that there were 29 species of urban landscape plant diseases,mainly powdery mildew and spot diseases.According to the characteristics of the diseases,the causes and problems of the diseases were analyzed,and the corresponding prevention and control measures were put forward.

Function Evolution and Landscape Planning Strategy of Inland Rivers in Beilun Port City of Ningbo

In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecological environment of river courses has been destroyed. In the past, remediationmeasures based on engineering and technology played a certain role, but can not “cure the root cause”. Itshould respect the historical evolution process of river courses, and highlight the ecological service functionand leisure tourism value of river courses from the coordination perspective of urban and rural ecologicalenvironment, economic industries, society and culture in the planning ideas of ecology, production, andlife integration. Four aspects of the measures are as below: protecting and repairing the ecological matrixof river courses;building green space system and maintaining flood control functions through the waternetwork;protecting cultural heritage along the rivers;developing waterfront leisure tourism scenic area.

Impact of coupling coordination development of port and city environments on urban economic competitiveness:Evidence from the coastal port cities in eastern China

Promoting the coupling coordination development of port and its hinterland city environments is an important way to improve urban economic competitiveness.Based on relevant data of 13 coastal port cities in eastern China from 2000 to 2018,this study explores the coupling coordination development of port and city environments and its impact on urban economic competitiveness by constructing the coupling coordination degree model and the panel threshold model.The research results show that:(1)In terms of the coupling coordination development of port and city environments,most coastal ports and their hinterland cities are in a state of moderate or serious disorder.Overall,the degree of coupling coordination of port and city environments needs to be further improved;(2)The coupling coordination degree of port and city environments has a significant impact on urban economic competitiveness,and this effect gradually increases with the development of the ports and the urban economy.Among the variables that impact the urban economic competitiveness,fixed assets investment and foreign trade are significant factors that can enhance urban economic competitiveness.(3)At present,there is a“U-shaped”relationship between the coupling coordination degree of port-city environments and the urban economic competitiveness.This relationship lies on the right side of the inflection point of the“U-shaped”curve.Therefore,following the concept of assigning priority to ecological development,expanding fixed assets investment and actively developing foreign trade can further enhance the urban economic competitiveness.

Influence of Lightning Disaster on Cities and Lightning Defense Measures

Under the influence of special terrain and climatic conditions,lightning weather in Ulanqab City is more frequent from June to August,and lightning disaster has become one of the important tasks of disaster prevention and mitigation.In this paper,based on the characteristics of lightning weather in Ulanqab City,the impact of lightning disaster on the city was analyzed,and lightning protection measures,such as strengthening supervision of lightning protection safety,establishing a long-term lightning protection mechanism,doing a good job in lightning protection construction and detection in key places,and further improving public awareness of lightning protection,were put forward to reduce and avoid urban lightning disasters as much as possible and ensure urban safety.

Application Strategies of Spatial Refinement Design in Ancient Cities Supported by Digital Te-Zhaoyu Ancient City in Qixian County as an Example

Digital technology provides a method of quantitative investigation and data analysis for contemporary landscape spatial analysis,and related research is moving from image recognition to digital algorithmic analysis,providing a more scientific and macroscopic way of research.The key to refinement design is to refine the spatial design process and the spatial improvement strategy system.Taking the ancient city of Zhaoyu in Qixian County,Shanxi Province as an example,(1)based on obtaining the integrated data of the ancient city through the drone tilt photography,the style and landscape of the ancient city are modeled;(2)the point cloud data with spatial information is imported into the point cloud analysis platform and the data analysis is carried out from the overall macroscopic style of the ancient city to the refinement level,which results in the formation of a more intuitive landscape design scheme,thus improving the precision and practicability of the landscape design;(3)Based on spatial big data,it starts from the spatial aggregation level,spatial distribution characteristics and other evaluation index system to achieve the refinement analysis of the site.Digital technology and methods are used throughout the process to explore the refined design path.

Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China

Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.

Structural Characteristics and Influencing Factors of Carbon Emission Spatial Association Network:A Case Study of Yangtze River Delta City Cluster,China

City cluster is an effective platform for encouraging regionally coordinated development.Coordinated reduction of carbon emissions within city cluster via the spatial association network between cities can help coordinate the regional carbon emission management,realize sustainable development,and assist China in achieving the carbon peaking and carbon neutrality goals.This paper applies the improved gravity model and social network analysis(SNA)to the study of spatial correlation of carbon emissions in city clusters and analyzes the structural characteristics of the spatial correlation network of carbon emissions in the Yangtze River Delta(YRD)city cluster in China and its influencing factors.The results demonstrate that:1)the spatial association of carbon emissions in the YRD city cluster exhibits a typical and complex multi-threaded network structure.The network association number and density show an upward trend,indicating closer spatial association between cities,but their values remain generally low.Meanwhile,the network hierarchy and network efficiency show a downward trend but remain high.2)The spatial association network of carbon emissions in the YRD city cluster shows an obvious‘core-edge’distribution pattern.The network is centered around Shanghai,Suzhou and Wuxi,all of which play the role of‘bridges’,while cities such as Zhoushan,Ma'anshan,Tongling and other cities characterized by the remote location,single transportation mode or lower economic level are positioned at the edge of the network.3)Geographic proximity,varying levels of economic development,different industrial structures,degrees of urbanization,levels of technological innovation,energy intensities and environmental regulation are important influencing factors on the spatial association of within the YRD city cluster.Finally,policy implications are provided from four aspects:government macro-control and market mechanism guidance,structural characteristics of the‘core-edge’network,reconfiguration and optimization of the spatial layout of the YRD city cluster,and the application of advanced technologies.

Construction land expansion and influencing factors of typical river valley cities in Northeast China: Taking Jilin City as an example

Jilin City is a typical river valley city in Northeast China.In this paper,the authors studied the spatial and temporal expansion characteristics of the built-up areas in Jilin City from 1990 to 2020 using the analysis of expansion speed and strength,fractal dimension,barycenter coordinate transfer index and sector analysis.The ultimate-goal is to analyze the driving and restrictive factors that affect the spatial expansion of river valley cities.The results indicate that(1)the expansion speed of urban land in Jilin City has been re-latively slow in the past 30 years,while only slightly faster in 2010–2020;(2)in the spatial dimension,Jilin City mainly expanded to the south,then to the west,and extensive expansion has resulted in complex mor-phology with little stability and compactness;(3)the expansion is affected by multiple factors,of which the positive factor is industrial development,while the restrictive factors include natural factors,population loss,etc.This study provides a case for the formulation of land use policies and land space planning in river valley cities.

Influence of Urban Street Greening Design under the Concept of Green Healthy Cities:A Case Study of Hefei City

In order to explore the influence of urban street greening,the street landscape of Changjiang West Road and Xiyou Road in Hefei City was selected as the research sample to study the design of urban street landscape under the concept of green healthy cities.The results show that the urban street landscape of Hefei City is single in design and plant type,and plant maintenance management is not good.It is proposed to strengthen the maintenance and management of street greening,increase the types of native plants,and improve cultural connotation,so as to enhance the artistry,regionalism and functionality of urban street landscape in Hefei City.

皖南伏岭A型花岗岩的成因——地球化学、锆石U-Pb年龄及Lu—Hf同位素特征

伏岭花岗岩体,位于江南造山带东段的皖浙相邻区,岩浆岩沿着近北东向的宁国—绩溪深大断裂断分布。笔者等对伏岭岩体鱼龙川(γ_(5)^(3-2))单元花岗岩开展了系统的全岩岩石地球化学、LA-ICPMS锆石U-Pb同位素年龄和锆石原位Lu—Hf同位素地球化学研究,结果表明,花岗岩的侵位年龄为131.8±0.9 Ma,富硅、富碱、贫钙、贫铁,具有较高的Rb、Th、U、Ga、Zr和Y含量,较低的Sr、Ba和Nb含量,稀土配分曲线呈现典型的“海鸥式”分布特征,显示强烈的负Eu异常;微量元素原始地幔标准化蛛网图显示明显的Ba、Sr、Nb的负异常。其高SiO_(2)含量和Rb/Sr值、低Ba、Sr含量具备江南造山带东段皖南地区A型花岗岩的典型特征。岩体具有同源岩浆演化特征,源区可能存在磷灰石、钛铁矿的分离结晶作用,而辉石类的分离较少。伏岭岩体主要来源于地壳中镁铁质岩石的部分熔融,其地球化学特征继承于源岩。锆石ε_(Hf)(t)变化范围较小,均在-7.0~-4.6之间,二阶段模式年龄(TDM2)为1478~1630 Ma,伏岭花岗岩可能由中元古代古老下地壳部分熔融形成。伏岭岩体的形成可能受到碰撞作用的影响,岩体形成于后碰撞期,中元古代的基底岩石被大范围的熔融,从而产生了伏岭A型花岗岩。

国产无载体镥[^(177)Lu]的制备及标记DOTA⁃TOC在神经内分泌肿瘤中的初步临床应用探讨

目的:阐述国产无载体镥[^(177)Lu]制备工艺及^(177)Lu标记1,4,7,10⁃四氮杂环十二烷⁃1,4,7,10⁃四乙酸⁃酪氨酸3⁃奥曲肽(1,4,7,10⁃tetraazacyclododecane⁃1,4,7,10⁃tetraacetic acid conjugated Tyr3⁃octreotide,DOTA⁃TOC)的方法,探讨国产^(177)Lu⁃DO⁃TA⁃TOC初步临床应用的安全性及有效性。方法:采用多级连续分离纯化制备国产无载体镥[^(177)Lu],全自动化模块标记合成^(177)Lu⁃DOTA⁃TOC,回顾分析南京医科大学附属南京医院4例仅接受了国产无载体镥[^(177)Lu]标记DOTA⁃TOC的肽受体放射性核素靶向治疗(peptide receptor radionuclide therapy,PRRT)神经内分泌肿瘤(neuroendocrine neoplasm,NEN)患者资料。结果:国产无载体镥[^(177)Lu]质控良好,铜<0.01,锌<0.01,铁<0.01,铅<0.15,镱未检出,放化纯>99%,细菌内毒素<2 EU/mL。国产^(177)Lu⁃DOTA⁃TOC自动化标记产率为(98.85±0.97)%,产品比活度为(80.96±7.47)GBq/μmol,无菌和内毒素检测均符合规定标准,标记产物中乙醇含量为0,放化纯大于99%。仅接受国产^(177)Lu⁃DOTA⁃TOC治疗的4例患者中,1例仅1次治疗后原发灶及转移灶几乎完全消失,1例治疗后1个月出现3级骨髓毒性,治疗后3个月恢复至正常,所有患者均未出现肾毒性。结论:国产无载体镥[^(177)Lu]标记DOTA⁃TOC质控合格,产率高,安全、耐受性好,对于无法手术切除的NEN患者具有较好疗效。无载体镥[^(177)Lu]的国产化和批量化生产将推动我国核医学诊疗一体化的发展。

Spatiotemporal evolution and prediction of habitat quality in Hohhot City of China based on the InVEST and CA-Markov models

With the acceleration of urbanization,changes in the urban ecological environment and landscape pattern have led to a series of prominent ecological environmental problems.In order to better coordinate the balanced relationship between city and ecological environment,we selected land use change data to evaluate the habitat quality in Hohhot City of China,which is of great practical significance for regional urban and economic development.Thus,the integrated valuation of ecosystem services and tradeoffs(InVEST)and Cellular Automata-Markov(CA-Markov)models were used to analyze,predict,and explore the Spatiotemporal evolution path and characteristics of urban land use,and forecast the typical evolution pattern of land use in 2030.The results showed that the land use types in Hohhot City changed significantly from 2000 to 2020,and the biggest change took place in cultivated land,grassland,shrub,and artificial surface.The decrease of cultivated land area and the increase of artificial surface area were the main impact trend of land use change.The average value of habitat quality had been decreasing continuously from 2000 to 2020,and the values of habitat degradation were 0.2605,0.2494,and 0.2934 in 2000,2010,and 2020,respectively,showing a decreasing trend.The decrease of habitat quality was caused by the needs of economic development and urban construction,as well as the impact of land occupation.During this evolution,many cultivated land and urban grassland had been converted into construction land.The simulated land use changes in 2030 are basically the same as those during 2000-2020,and the habitat quality will still be declining.The regional changes are influenced by the urban rapid development and industrial layout.These results can provide decision-making reference for regional urban planning and management as well as habitat quality evaluation.

文旅融合:“Citywalk”热潮下的冷思考

“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。

Residential environmental evaluation of local cities considering regional characteristic and personal residential preference—a case study of Saga City,Japan

Questionnaire surveys and subjective evaluations on residential environment were performed in order to grasp the main factors of residential environment of small local cities. The suitable evaluation index system was established, and the regional residential environment characteristics and personal residential preference types were analyzed, so that their influence on residential environment evaluation could be grasped. The results can be applied to the residential environment planning, construction and monitoring of local cities.

基于LU分解的安全外包求解线性代数方程组方法

由于现有协议的安全性为基于某种安全假设的计算安全,依赖于敌手的计算能力,因此,本文针对恶意敌手模型,使用矩阵伪装技术对方程的系数矩阵进行隐藏,结合矩阵的LU分解(lower-upper decomposition)算法,提出一种新的信息论安全外包求解线性代数方程组(information-theoretically secure outsourcing of linear algebraic equations,ITS-OutsLAE)方法 .与之前的研究相比,在保持计算和通信复杂度与现有最优方案保持一致的同时,首次将方程组唯一解的安全性提升至信息论安全(完美保密).给出了形式化的安全性证明,并通过理论分析和实验证明了所提方法的实用性.