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Research on Ultra-Short-Term Photovoltaic Power Forecasting Based on Parallel Architecture TCN-BiLSTM with Temporal-Spatial Attention Mechanism
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作者 Hongbo Sun Xingyu Jiang +4 位作者 Wenyao Sun Yi Zhao Jifeng Cheng Xiaoyi Qian Guo Wang 《Energy Engineering》 2026年第4期303-320,共18页
The accuracy of photovoltaic(PV)power prediction is significantly influenced by meteorological and environmental factors.To enhance ultra-short-term forecasting precision,this paper proposes an interpretable feedback ... The accuracy of photovoltaic(PV)power prediction is significantly influenced by meteorological and environmental factors.To enhance ultra-short-term forecasting precision,this paper proposes an interpretable feedback prediction method based on a parallel dual-stream Temporal Convolutional Network-Bidirectional Long Short-Term Memory(TCN-BiLSTM)architecture incorporating a spatiotemporal attention mechanism.Firstly,during data preprocessing,the optimal historical time window is determined through autocorrelation analysis while highly correlated features are selected as model inputs using Pearson correlation coefficients.Subsequently,a parallel dual-stream TCN-BiLSTM model is constructed where the TCN branch extracts localized transient features and the BiLSTM branch captures long-term periodic patterns,with spatiotemporal attention dynamically weighting spatiotemporal dependencies.Finally,Shapley Additive explanations(SHAP)additive analysis quantifies feature contribution rates and provides optimization feedback to the model.Validation using operational data from a PV power station in Northeast China demonstrates that compared to conventional deep learning models,the proposed method achieves a 17.6%reduction in root mean square error(RMSE),a 5.4%decrease in training time consumption,and a 4.78%improvement in continuous ranked probability score(CRPS),exhibiting significant advantages in both prediction accuracy and generalization capability.This approach enhances the application effectiveness of ultra-short-term PV power forecasting while simultaneously improving prediction accuracy and computational efficiency. 展开更多
关键词 Ultra-short-term forecasting temporal convolutional network bidirectional long short-term memory parallel dual-stream architecture temporal-spatial attention SHAP contribution analysis
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A Study on the Rail Transit Economic Field and Its Interactive Development Relationship with Cities from the Temporal-Spatial Perspective
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作者 Xiaorong Wang 《Proceedings of Business and Economic Studies》 2025年第5期11-19,共9页
As metropolitan areas expand spatially,they encounter constraints imposed by the fixed daily time budget.Rail transit enhances transport efficiency,reduces costs,and facilitates the formation of a“transit economic fi... As metropolitan areas expand spatially,they encounter constraints imposed by the fixed daily time budget.Rail transit enhances transport efficiency,reduces costs,and facilitates the formation of a“transit economic field”centered on rail networks,thereby alleviating such temporal-spatial pressures.This paper adopts an integrated temporal-spatial analytical framework.Following a conceptual clarification of the transit economic field,it dissects the mechanisms through which rail transit improves mobility and examines how this field influences urban spatial patterns,temporal dynamics,and their interrelationships.It constructs a theoretical framework to explain the co-development of transit economic fields and cities,supplemented by empirical case studies.The key findings are as follows:Firstly,the transit economic field represents a high-density development model that expands both horizontally and vertically around rail networks.It mitigates temporal-spatial conflicts.Secondly,with rail networks as the core,the field integrates diverse spatial functions,facilitating the establishment of economic connections and stabilizing temporal-spatial relationships.Thirdly,the transit economic field contributes to the preservation of urban natural ecosystems and enhances urban livability.Overall,this research can provide insights for promoting rail transit-oriented development transitions in large cities and urban agglomerations. 展开更多
关键词 Rail transit Rail transit economic field temporal-spatial relationship ACCESSIBILITY
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人工智能如何更好地促进人类文明发展?——从Image、Concept到Sign的重大跨越
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作者 许晓东 《长沙理工大学学报(社会科学版)》 2026年第2期47-56,共10页
人工智能的爆发式发展本质是现代启蒙理性的极致延伸,其技术演进遵循Image、Concept、Sign的分化逻辑。文章以《启蒙辩证法》为核心理论工具,紧扣理性与权力相互渗透、启蒙双重视角、文明三阶段等核心观点,系统分析人工智能从数据图像... 人工智能的爆发式发展本质是现代启蒙理性的极致延伸,其技术演进遵循Image、Concept、Sign的分化逻辑。文章以《启蒙辩证法》为核心理论工具,紧扣理性与权力相互渗透、启蒙双重视角、文明三阶段等核心观点,系统分析人工智能从数据图像的抽象化、算法概念的工具化,到符号体系的支配化的跨越演进过程。人工智能的发展潜力,既源于启蒙理性对世界的祛魅与重构能力,也内含启蒙自我消解的风险。工具理性的单向强化、权力对技术的裹挟导致图像与符号的彻底分离,技术理性沦为新的支配性意识形态。只有回归《启蒙辩证法》的批判维度,重构理性的双重内涵、消解符号对现实的异化、解构技术权力的垄断格局,才能让人工智能摆脱技术极权主义风险,成为服务人类文明的积极力量。 展开更多
关键词 人工智能 《启蒙辩证法》 Image—concept—Sign 工具理性 技术批判
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Exploration and Practical Research on the Construction Model of the Emergency Care System Based on the Concept of“Linkage”
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作者 Yan Li 《Journal of Clinical and Nursing Research》 2026年第1期138-144,共7页
Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching t... Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching the construction of an emergency care system based on the concept of“linkage”,delving into its theoretical foundations,exploring innovative construction models,and analyzing practical cases.The study indicates that an emergency care system under the“linkage”concept can effectively integrate resources and enhance efficiency,providing new insights for improving the construction of the emergency care system.It aims to promote the development of the emergency care system towards a more scientific,efficient,and collaborative direction. 展开更多
关键词 Linkage concept Emergency care system Construction model Practical cases
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Proposal,Promotion,and Practice and Application of Damage Control Surgery Concept in Trauma Treatment at Grassroots Hospitals
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作者 Jingcheng Chen Yongzhan Chen Jing Xu 《Journal of Clinical and Nursing Research》 2026年第1期366-372,共7页
The concept of Damage Control Surgery(DCS)emphasizes prioritizing hemorrhage control,preventing hypothermia,correcting coagulopathy,and acidosis in trauma treatment.The application of the DCS concept in trauma treatme... The concept of Damage Control Surgery(DCS)emphasizes prioritizing hemorrhage control,preventing hypothermia,correcting coagulopathy,and acidosis in trauma treatment.The application of the DCS concept in trauma treatment at grassroots hospitals faces numerous challenges such as limited resources,high technical difficulty,and insufficient multidisciplinary collaboration.Therefore,DCS strategies need to be adapted to simplified processes to create conditions for subsequent treatment.This paper retrieves relevant literature to discuss the proposal,promotion,and application of the DCS concept,aiming to provide evidence-based basis for optimizing trauma treatment outcomes at grassroots hospitals. 展开更多
关键词 Damage control surgery concept promotion Grassroots hospitals Trauma treatment
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A conceptual analysis of reflective supervision for creating a positive intensive care practice environment
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作者 Mpho Grace Chipu 《International Journal of Nursing Sciences》 2026年第1期88-95,共8页
Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant... Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant’s eight-step concept analysis approach was utilized to identify and define the attributes,antecedents,and consequences of reflective supervision in the ICU.An extensive literature search was conducted across various databases,including Google Scholar,CINAHL,PubMed.Articles published from 2005 to 2025 were identified.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020 statement to indicate the included articles and extract related data based on relevance.Results Forty articles were included in the analysis.The identified attributes included the supervisor-supervisee relationship,effective communication,teamwork,collaborations,reflection,competencies,feedback,continuous support,and autonomous choice.The identified antecedents included participation,supportive supervision,flexibility,open-door policy,training,and motivation.Consequences impacting the success of reflective supervision were identified as promotion of resiliency,autonomy,work-life balance,self-awareness,increased self-esteem,professional development,critical thinking,increased job satisfaction,and enhanced commitment.Conclusions Reflective supervision is a complex professional self-care strategy that enhances ICU practice,by promoting nurses’well-being,self-awareness,therapeutic skills,and professional development. 展开更多
关键词 concept analysis Intensive Care Unit NURSING Positive environment Reflective supervision
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The concept, key technologies and applications of temporal-spatial information infrastructure 被引量:1
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作者 Chengming Li Po Liu +1 位作者 Jie Yin Xiaoli Liu 《Geo-Spatial Information Science》 CSCD 2016年第2期中插6-中插6,148-156,共10页
Smart city is the development of digital city; as its main supporting technology, the digital city geo-spatial framework has to be upgraded to the temporal-spatial information infrastructure (TSII). first, this paper ... Smart city is the development of digital city; as its main supporting technology, the digital city geo-spatial framework has to be upgraded to the temporal-spatial information infrastructure (TSII). first, this paper proposes the concept and basic framework of smart city and defines the concept of TSII - processes, integration, mining analysis, and share time-stamps geographic data - and the related policy, regulations and standards, technology, facilities, mechanism, and human resources. The framework has four components: the benchmark of time and space, temporal-spatial big data, the cloud service platform and the related supporting environment. Second, the temporal-spatial big data and cloud service platform are elaborated. finally, an application of TSII constructed by the Xicheng District Planning Bureau in Beijing is introduced, which provides a useful reference for the construction of smart city. 展开更多
关键词 Smart CITY temporal-spatial information INFRASTRUCTURE CLOUD platform BIG DATA DATA MINING
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DriftXMiner: A Resilient Process Intelligence Approach for Safe and Transparent Detection of Incremental Concept Drift in Process Mining
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作者 Puneetha B.H Manoj Kumar M.V +1 位作者 Prashanth B.S. Piyush Kumar Pareek 《Computers, Materials & Continua》 2026年第1期1086-1118,共33页
Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental con... Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts. 展开更多
关键词 Process mining concept drift gradual drift incremental drift clustering ensemble techniques process model event log
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SCAN:Structural Clustering with Adaptive Thresholds for Intelligent and Robust Android Malware Detection under Concept Drift
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作者 Kyoungmin Roh Seungmin Lee +2 位作者 Seong-je Cho Youngsup Hwang Dongjae Kim 《Computer Modeling in Engineering & Sciences》 2026年第3期1124-1163,共40页
Many machine learning-based Android malware detection often suffers from concept drift,where models trained on historical data fail to generalize to evolving threats.This paper proposes SCAN(Structural Clustering with... Many machine learning-based Android malware detection often suffers from concept drift,where models trained on historical data fail to generalize to evolving threats.This paper proposes SCAN(Structural Clustering with Adaptive thresholds for iNtelligent Android malware detection),a hybrid intelligent framework designed to mitigate concept drift without retraining.SCAN integrates Gaussian Mixture Models(GMMs)-based clustering with cluster-wise adaptive thresholding and supervised classifiers tailored to each cluster.A key challenge in clusteringbased malware detection is cluster-wise class imbalance,where clusters contain disproportionate distributions of benign and malicious samples.SCAN addresses this issue through adaptive thresholding,which dynamically adjusts the decision boundary of each cluster according to its malicious-to-benign ratio.In the final training stage,four supervised learning algorithms—Random Forest(RF),Support Vector Machine(SVM),k-NN,and XGBoost—are applied within the GMM-defined clusters.We train SCAN on Android applications collected from 2014-2017 and test it with applications from 2018-2023.Experimental results demonstrate that SCAN combined with RF consistently achieves superior performance,with both average accuracy and average F1-score exceeding 91%.These findings confirm SCAN’s robustness to concept drift and highlight its potential as a sustainable and intelligent solution for long-term Android malware detection in the real world. 展开更多
关键词 Android malware detection concept drift intelligent hybrid framework gaussian mixture model(GMM) class imbalance adaptive thresholding
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Temporal-spatial Changes in Inner Mongolian Grassland Degradation during Past Three Decades 被引量:10
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作者 张清雨 吴绍洪 +1 位作者 赵东升 戴尔阜 《Agricultural Science & Technology》 CAS 2013年第4期676-683,共8页
[Objective] This study aimed to analyze the temporal-spatial variation of Inner Mongolian grassland degradation during past three decades. [Method] The dis- tribution characteristics of grassland were described by lan... [Objective] This study aimed to analyze the temporal-spatial variation of Inner Mongolian grassland degradation during past three decades. [Method] The dis- tribution characteristics of grassland were described by land use types supervised classification with TM/ETM. Then, temporal-spatial changes of grassland coverage were quantified by the mean of maximum vegetation coverage in last 30 years. Lastly, the grassland degradation reasons were explored through statistic analysis between the grassland coverage and precipitation, temperature and grazing intensity. [Result] The grassland degradation index of Inner Mongolia was increased from 1.38 to 1.68, and the smallest was 1.28 in 2005s. Grassland degradation and improve- ment were concurrent after 1980s, but grassland degradation was the major change trend for Inner Mongolia grassland. The area of grassland degradation was enlarged from 18.08×10^4 km2 in 1980s to 22.47×10^4 km2 in 2010s on the whole and distribu- tion range was shifted from central-eastern to west in Inner Mongolia that mainly distributed on Hulun Buir and Xilin Gol grassland in 1980s and Ordos and Alax grassland in 2010s. The grassland area of degradation had a rising trend form 1980s to 1995s, then reduced to 10.8x104 km2 in 2005s, and decreased in 2010s, which mainly speared in the west of Xilin Gol grassland. [Conclusion] Inner Mongo-lian grassland degradation were become more seriously in last 30 years because that temperature, precipitation and graze intensities change, which not performance on decreasing coverage but grassland areas. 展开更多
关键词 Grassland degradation temporal-spatial change Influencing factor Inner Mongolia
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Temporal-spatial Distribution Model of Cold Chain Logistics for Vegetables
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作者 陈绍慧 张鹏 +1 位作者 鲁晓翔 李江阔 《Agricultural Science & Technology》 CAS 2012年第5期1115-1118,共4页
[Objective] The aim was to study on temporal-spatial distribution model of cold chain logistics for vegetables. [Method] Broccoli was taken as an example. Detailedly, time-space distribution model of cold chain logist... [Objective] The aim was to study on temporal-spatial distribution model of cold chain logistics for vegetables. [Method] Broccoli was taken as an example. Detailedly, time-space distribution model of cold chain logistics for broccoli was proposed from standpoints of costs and benefits based on changes of time and space, and a comprehensive evaluation was made on timeliness, efficiency, risks, added- value of products and satisfaction of information in cold-chain logistics. [Result] The efficiency of cold chain logistics for vegetable can be greatly improved by temporal- spatial distribution model of cold chain logistics. [Conclusion] Costs and benefits of vegetables in temporal-apstial distribution could be evaluated by the model. 展开更多
关键词 VEGETABLE Cold-chain logistics temporal-spatial distribution BROCCOLI
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Temporal-Spatial Variability of Soil Organic Carbon Stocks in a Rehabilitating Ecosystem 被引量:43
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作者 ZHANGShi-Rong SUNBo +2 位作者 ZHAOQi-Guo XIAOPeng-Fei SHUJian-Ying 《Pedosphere》 SCIE CAS CSCD 2004年第4期501-508,共8页
In global change research, changes of soil organic carbon (SOC) reservoirs intropical and subtropical regions are still unknown. The temporal-spatial variability of SOC stockswas determined in a basin of over 579 km^2... In global change research, changes of soil organic carbon (SOC) reservoirs intropical and subtropical regions are still unknown. The temporal-spatial variability of SOC stockswas determined in a basin of over 579 km^2 in subtropical China from 1981to 2002. ArcGIS8.l softwarewas utilized for spatial analysis of semivariance, ordinary kriging (OK), and probability kriging(PK). Grid and hierarchical approaches were employed for the sampling scenario in 2002 with 106Global Position System (GPS) established spots sampled. Bulk topsoil samples (0—30 cm) werecollected at three random sites on each spot. The SOC content for 1981 came from the SOC map of theSecond National Soil Survey. Geostatistical results of the nugget to sill ratio (0.215-0.640)in therehabilitating ecosystem indicated a moderate spatial dependence for SOC on this large scale. Therange of SOC changed from 2.04 km in 1981 to 7.15 km in 2002. The mean topsoil SOC increased by 4.6%from 10.63 g kg^(-1) (1981) to 11.12 g kg^(-1)(2002). However, during this 21-year period 25.2% ofthe total basin area experienced a decrease in SOC. Also, the probability kriging results showedthat the geometric mean probabilities of SOC <= 6.0 g kg^(-1), <= 11.0 g kg^(-1) and > 15.0 gkg^(-1) were 0.188, 0.534 and 0.378, respectively in 2002, comparing to 0.234, 0.416 and 0.234 inthat order in 1981, respectively. The SOC storage in the topsoil increased by 17.0% during this timewith the main increase occurring in forests and cultivated land,which amounted to 82.5% and 17.0%of the total increase, respectively. 展开更多
关键词 ordinary kriging probability kriging rehabilitating ecosystem soil organiccarbon temporal-spatial variability
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Sand-dust storms in China: temporal-spatial distribution and tracks of source lands 被引量:11
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作者 QIU Xin-fa1, ZENG Yan2, MIAO Qi-long2 (1. Urban & Resource Department, Nanjing University, Nanjing 210009, China 2. Department of Environmental Science, Nanjing Institute of Meteorology, Nanjing 210044, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期253-260,共9页
Sand-dust storm is a special natural disaster that frequently occurs in deserts and their surrounding areas. With the data published onSurface Meteorological Monthly Bulletin andSurface Chart during 1971–1996, the te... Sand-dust storm is a special natural disaster that frequently occurs in deserts and their surrounding areas. With the data published onSurface Meteorological Monthly Bulletin andSurface Chart during 1971–1996, the temporal-spatial distribution and annual variation of sand-dust storms are analyzed on the basis of the case study of atmospheric processes. Furthermore, the tracks and source areas of sand-dust storms are determined with the aid of GIS. The results show that except some parts of Qinghai Province and Inner Mongolia as well as Beijing, sand-dust storms decrease apparently in time and space in recent decades in China. Sand-dust storms occur most frequently in spring, especially in April. According to their source areas, sand-dust storms are classified into two types, i.e., the inner-source and outer-source sand-dust storms. Most of the outer-source sand-dust storms move along the north and west tracks. The north-track outer-source sand-dust storms always intrude into China across the Sino-Mongolian border from Hami, a city in the eastern part ofXinjiang, to Xilin Gol, a league in Inner Mongolia, while the west-track ones intrude into China from both southern and northern Xinjiang. The source lands of inner-source sand-dust storms concentrate in the Taklimakan Desert and its surrounding areas in southern Xinjiang, southern part of the Junggar Basin in north of Xinjiang, the Hexi Corridor in western Gansu Province, the dry deserts of Inner Mongolia and the Qaidam Basin in Qinghai. 展开更多
关键词 sand-dust storm temporal-spatial distribution TRACKS source lands
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Temporal-spatial distribution and variability of cadmium contamination in soils in Shenyang Zhangshi irrigation area,China 被引量:8
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作者 SUN Li-na ZHANG Yao-hua +3 位作者 SUN Tie-heng GONG Zong-qiang LIN Xin LI Hai-bo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1241-1246,共6页
Heavy metal contamination in soils has been of wide concern in China in the last several decades. The heavy metal contamination was caused by sewage irrigation, mining and inappropriate utilization of various agrochem... Heavy metal contamination in soils has been of wide concern in China in the last several decades. The heavy metal contamination was caused by sewage irrigation, mining and inappropriate utilization of various agrochemicals and pesticides and so on. The Shenyang Zhangshi irrigation area (SZIA) in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 years duration. This study investigated the spatial distribution and temporal variation of soil cadmium contamination in the SZIA. The soil samples were collected from the SZIA in 1990 and 2004; Cd of soils was analyzed and then the spatial distribution and temporal variation of Cd in soils was modelled using kriging methods. The kriging map showed that long-term sewage irrigation had caused serious Cd contamination in topsoil and subsoil. In 2004, the Cd mean concentrations were 1.698 and 0.741 mg/kg, and the maxima 10.150 and 7.567 mg/kg in topsoils (0-20 cm) and subsoils (20-40 cm) respectively. These values are markedly more than the Cd levels in the second grade soil standard in China. In 1990, the Cd means were 1.023 and 0.331 mg/kg, and the maxima 9.400 and 3.156 mg/kg, in topsoils and subsoils respectively. The soil area in 1990 with Cd more than 1.5 mg/kg was 2701 and 206.4 hnl2 in topsoils and subsoils respectively; and in 2004, it was 7592 and 1583 hm^2, respectively. Compared with that in 1990, the mean and maximum concentration of Cd, as well as the soil area with Cd more than 1.5 mg/kg had all increased in 2004, both in topsoils and subsoils. 展开更多
关键词 temporal-spatial distribution cadmium contamination of soil Zhangshi sewage irrigation area (ZSIA) Shenyang
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Impact of Holocene environmental change on temporal-spatial distribution of Neolithic sites in Huaihe River Basin, Anhui Province 被引量:5
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作者 HUANG Run ZHU Cheng +1 位作者 GUAN Yong ZHENG Chaogui 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期199-208,共10页
The Huaihe River basin of Anhui is not only a transitional zone of physical geography, but also a convergent area of many cultures in China. It is one of the sensitive ecotones to global changes and the birthplace of ... The Huaihe River basin of Anhui is not only a transitional zone of physical geography, but also a convergent area of many cultures in China. It is one of the sensitive ecotones to global changes and the birthplace of Chinese civilization. Using the field archaeological data and the sporo-pollens and the age data of the drilling cores, we analysed Neolithic cultural development and environmental evolution in the Huaihe River basin of Anhui. According to the combination of some research results in archaeology with environmental evolution research, this paper discusses the relationship between culture and environment in the Huaihe River basin of Anhui. The Neolithic cultural development was strongly impacted by the environmental change. The primitive culture (Shishanzi) was developed in the beginning of the Holocene Megathermal Period with distinct regional feature of the culture. From 6.5 kaBP to 5.5 kaBP, the climate changed warmer and wetter. The frequent occurrence of flood and waterlog due to such a climate regime and high sea level caused the earth's surface environment deteriorated in the Huaihe River basin of Anhui and the interruption of the Neolithic cultural development, hence a lack of archaeological sites. From 5.5 kaBP to 4.0 kaBP, the climate changed from wet to dry, the natural environment was propitious to human survival. Dawenkou Culture and Longshan Culture flourished in this period. The Neolithic cultural development, the number of the sites and their distribution characteristics of the sites in the study area differed apparently from those in Central China and Shandong Province. 展开更多
关键词 HOLOCENE environmental change Neolithic site temporal-spatial distribution Huaihe Riverbasin of Anhui
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Long-term temporal-spatial dynamics of marine coastal water quality in the Tolo Harbor,Hong Kong,China 被引量:4
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作者 XUFu-liu K.C.LAM +2 位作者 R.W.Dawson TAOShu Y.D.CHEN 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期161-166,共6页
The long-term temporal and spatial dynamics of marine coastal water quality in Tolo Harbor, Hong Kong were explored. The Harbor is divided into three zones represented as Harbor, Buffer, and Channel Subzones. The time... The long-term temporal and spatial dynamics of marine coastal water quality in Tolo Harbor, Hong Kong were explored. The Harbor is divided into three zones represented as Harbor, Buffer, and Channel Subzones. The time range for the study covers the period from the 1970s to the 1990s. The selected indicators for the comprehensive assessment of water quality consist of physical, chemical and biological aspects, including suspended solids(SS), Secchi disk depth(SD), 5-day biochemical oxygen demand(BOD\-5), total nitrogen(TN), total phosphorus(TP), faecal coliform, chlorophyll-a(Chl-a), and the number of red tide occurrences. The results indicated the presence of obvious temporal and spatial trends with regard to changes in water quality. Spatially, water quality in the Channel Subzone is the best, while that in the Harbor Subzone is the worst. On a temporal basis, the average trend from bad to good was 1980s>1990s>1970s as indicated by most of the selected water quality indicators. Water quality during the late 1980s reached its worst level with the lowest SD, the highest BOD\-5, TN, TP, Chl-a concentrations, and the number of red tide occurrences. These long-term temporal-spatial water quality trends were also found in other studies of the Tolo Harbor. The large quantity of pollutants produced as a result of increasing population, industrial and commercial actives, and urbanization and industrialization trends in both Shatin and Tai Po seem to be primarily responsible for the changes in marine coastal water quality. 展开更多
关键词 temporal-spatial dynamics water quality INDICATORS pollution load Tolo Harbor
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High-resolution algorithm based on temporal-spatial extrapolation 被引量:3
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作者 Xueya Yang Baixiao Chen Feilin Qi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第1期9-15,共7页
To enhance the resolution of parameter estimation with limited samples received by a short passive array,an iterative nonparametric algorithm for estimating the frequencies and direction-of-arrivals(DOAs)of signals is... To enhance the resolution of parameter estimation with limited samples received by a short passive array,an iterative nonparametric algorithm for estimating the frequencies and direction-of-arrivals(DOAs)of signals is proposed.The cost function is constructed using 12-norm Gaussian entropy combined with an additional constraint,12-norm constraint or linear constraint.By minimizing the cost functions in the temporal and the spatial dimensions using corresponding iteration algorithms respectively,the sparse discrete Fourier transforms(DFTs)of temporal and spatial samples are obtained to represent the extrapolated sequences with much larger sizes than the original samples.Then frequency and angle estimates are obtained by performing the traditional simple methods on the extrapolated sequences.It is shown that the proposed algorithm offers increased resolution and significantly reduced sidelobes compared with the periodogram and beamforming based methods.And it achieves high precision compared with the high-resolution method with lower computational burden.Some numerical simulations and real data processing results are presented to verify the effectiveness of the method. 展开更多
关键词 temporal-spatial extrapolation frequency estimation DIRECTION-OF-ARRIVAL discrete Fourier transform
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Effect of water level fluctuations on temporal-spatial patterns of foraging activities by the wintering Hooded Crane(Grus monacha) 被引量:8
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作者 Dongmei Zhang Lizhi Zhou Yunwei Song 《Chinese Birds》 CSCD 2015年第3期169-177,共9页
Background:The Yangtze River floodplain provides important wintering habitats for Hooded Cranes(Grus monacha) in China.Fluctuations in the water level change foraging habitat and food availability,affecting their temp... Background:The Yangtze River floodplain provides important wintering habitats for Hooded Cranes(Grus monacha) in China.Fluctuations in the water level change foraging habitat and food availability,affecting their temporal-spatial patterns of foraging activities.It is of considerable importance to investigate the effect of these fluctuations on food availability for wintering Hooded Cranes and their foraging response to these changes.Understanding their behavior patterns is beneficial in protecting the wintering crane population and restoring their wintering habitats.Methods:A field survey of the winter behavior of cranes was carried out at Shengjin Lake from November in 2013 to April in 2014.Habitat variables,as well as the spatial distribution and behavior patterns of wintering cranes at their foraging sites during five stages of water level fluctuation were collected.Based on this data we analyzed the relationship of foraging behavior relative to water level fluctuations and habitat types.Results:The foraging habitats used by Hooded Cranes varied at the different water level stages.As the water level decreased,the use of meadows and mudflats increased.When the water dropped to its lowest level,the use by the Hooded Crane in the mudflats reached a peak.There were statistically significant differences in time budget in the three types of habitats over the five stages of the water level.In the mudflats,the foraging behavior and maintenance behavior varied significantly with the water level,while the alert behavior showed little variation.Analysis of a generalized linear model showed that the five water level stages and three habitat types had a significant effect on foraging behavior,while the combined effect of these two variables was significant on the foraging time budget and the length of foraging activity of the Hooded Crane.Conclusions:With the decrease in the water level,the use of mudflats by Hooded Cranes increased correspondingly.Food availability in different habitats was affected by changes in the water level.The Hooded Crane adjusted its foraging patterns and made full use of the three available types of habitat in order to acquire enough food in response to fluctuations in the water level. 展开更多
关键词 Water level FLUCTUATIONS FORAGING activity temporal-spatial pattern Hooded CRANE GRUS monacha
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Determining the road traffic accident hotspots using GIS-based temporal-spatial statistical analytic techniques in Hanoi,Vietnam 被引量:5
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作者 Khanh Giang Le Pei Liu Liang-Tay Lin 《Geo-Spatial Information Science》 SCIE CSCD 2020年第2期153-164,共12页
This study applied GIS-based statistical analytic techniques to investigate the influence of accident Severity Index(SI)on temporal-spatial patterns of accident hotspots related to the specific time intervals of day a... This study applied GIS-based statistical analytic techniques to investigate the influence of accident Severity Index(SI)on temporal-spatial patterns of accident hotspots related to the specific time intervals of day and seasons.Road Traffic Accident(RTA)data in 3 years(2015-2017)in Hanoi,Vietnam were used to analyze and test this approach.Firstly,the RTA data were divided into four seasons in accordance with Hanoi's weather conditions and the time intervals such as the daytime,nighttime,or peak hours.Then,the Kernel Density Estimation(KDE)method was applied to analyze hotspots according to the time intervals and seasons.Finally,the results were presented by using the comap technique.This study considered both analyses with and without SI.The accident SI measures the seriousness of an accident.The approach method is to give higher weights to the more serious accidents,but not with the extremely high values calculated on a direct rate to the accident expenditures.The results showed that both analyses determined the relatively similar hotspots,but the rankings of some hotspots were quite different due to the integration of SI.It is better to take into account SI in determining RTA hotspots because the gained results are more precise and the rankings of hotspots are more accurate.From there,the traffic authorities can easily understand the causes behind each accident and provide reasonable solutions to solve the most dangerous hotspots in case of limited budget and resources appropriately.This is also the first study about this issue in Vietnam,so the contribution of the article will help the traffic authorities easily solve this problem not only in Hanoi but also in other cities. 展开更多
关键词 Road Traffic Accident(RTA) HOTSPOT GIS temporal-spatial analysis Kernel Density Estimation(KDE) Severity Index(SI)
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Quantitative method for evaluating detailed volatility of wind power at multiple temporal-spatial scales 被引量:6
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作者 Yongqian Liu Han Wang +3 位作者 Shuang Han Jie Yan Li Li Zixin Chen 《Global Energy Interconnection》 2019年第4期318-327,共10页
With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to eva... With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to evaluate the volatility of wind power only consider its overall characteristics, such as the standard deviation of wind power, the average of power variables, etc., while ignoring the detailed volatility of wind power, that is, the features of the frequency distribution of power variables. However, how to accurately describe the detailed volatility of wind power is the key foundation to reduce its adverse influences. To address this, a quantitative method for evaluating the detailed volatility of wind power at multiple temporal-spatial scales is proposed. First, the volatility indexes which can evaluate the detailed fluctuation characteristics of wind power are presented, including the upper confidence limit, lower confidence limit and confidence interval of power variables under the certain confidence level. Then, the actual wind power data from a location in northern China is used to illustrate the application of the proposed indexes at multiple temporal(year–season–month–day) and spatial scales(wind turbine–wind turbines–wind farm–wind farms) using the calculation time windows of 10 min, 30 min, 1 h, and 4 h. Finally, the relationships between wind power forecasting accuracy and its corresponding detailed volatility are analyzed to further verify the effectiveness of the proposed indexes. The results show that the proposed volatility indexes can effectively characterize the detailed fluctuations of wind power at multiple temporal-spatial scales. It is anticipated that the results of this study will serve as an important reference for the reserve capacity planning and optimization dispatch in the electric power system which with a high proportion of renewable energy. 展开更多
关键词 Wind power Detailed VOLATILITY Frequency distribution MULTIPLE temporal-spatial scales TYPICAL DAYS Forecasting accuracy
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