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Agricultural intensity for sustainable regional development:A case study in peri-urban areas of Karawang Regency,Indonesia
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作者 Setyardi Pratika MULYA Delik HUDALAH 《Regional Sustainability》 2024年第1期119-136,共18页
Peri-urban areas are playing an increasingly crucial role in the agricultural development and intensification in Indonesia.Peri-urban agriculture is highly vulnerable to change compared with urban and rural agricultur... Peri-urban areas are playing an increasingly crucial role in the agricultural development and intensification in Indonesia.Peri-urban agriculture is highly vulnerable to change compared with urban and rural agriculture,due to its location in transitional areas.Indicators of peri-urban agricultural intensity can help guide regional development.In this study,we assessed the sustainability of peri-urban areas based on agricultural intensity in Karawang Regency,Indonesia.We developed a village-based index to assess the region’s agricultural intensity by rescaling the village agriculture index(VAI)and combining the local sustainability index(LSI)with factor analysis.Since the unit of analysis is the village,we modified the LSI to the village sustainability index(VSI).In addition,we also developed a logical matrix analysis to determine the level of agricultural sustainability(LoAS)of each village.The combined results of the three indices(VAI,VSI,and LoAS)generated information about agricultural sustainability.The results indicated that peri-urban villages with high agricultural intensity tended to exhibit low levels of social welfare,economic development,and disaster risk.Moreover,high agricultural intensity did not necessarily ensure the prosperity of the people.Instead,there was the economic disparity among the villages in the study area.Encouraging diversity of agricultural intensity seems to be more critical than promoting agricultural intensity itself.Overall,this study highlights the distinctive characteristics and dynamic of peri-urban areas.New approaches,variables,and information regarding the combination of agricultural intensity and sustainability need to be developed as valuable tools for regional planning. 展开更多
关键词 Agricultural intensity Village agriculture index(VAI) Village sustainability index(VSI) Level of agricultural sustainability(LoAS) Peri-urban areas Indonesia
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Basal internode elongation of rice as affected by light intensity and leaf area 被引量:6
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作者 Xuhua Zhong Kaiming Liang +5 位作者 Bilin Peng Ka Tian Xiaojuan Li Nongrong Huang Yanzhuo Liu Junfeng Pan 《The Crop Journal》 SCIE CAS CSCD 2020年第1期62-70,共9页
Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of bas... Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of basal internodes persists.The objectives of this study were(1)to identify key factors affecting the elongation of basal internodes and(2)to establish a quantitative relationship between basal internode length and canopy indices.An inbred rice cultivar,Yinjingruanzhan,was grown in two split-plot field experiments with three N rates(0,75,and 150 kg N ha−1 in early season and 0,90,and 180 kg N ha−1 in late season)as main plots,three seedling densities(16.7,75.0,and 187.5 seedlings m−2)as subplots,and three replications in the 2015 early and late seasons in Guangzhou,China.Light intensity at base of canopy(Lb),light quality as determined from red/far-red light ratio(R/FR),light transmission ratio(LTR),leaf area index(LAI),leaf N concentration(NLV)and final length of second internode(counted from soil surface upward)(FIL)were recorded.Higher N rate and seedling density resulted in significantly longer FIL.FIL was negatively correlated with Lb,LTR,and R/FR(P<0.01)and positively correlated with LAI(P<0.01),but not correlated with NLV(P>0.05).Stepwise linear regression analysis showed that FIL was strongly associated with Lb and LAI(R2=0.82).Heavy N application to pot-grown rice at the beginning of first internode elongation did not change FIL.We conclude that FIL is determined mainly by Lb and LAI at jointing stage.NLV has no direct effect on the elongation of basal internodes.N application indirectly affects FIL by changing LAI and light conditions in the rice canopy.Reducing LAI and improving canopy light transmission at jointing stage can shorten the basal internodes and increase the lodging resistance of rice. 展开更多
关键词 Internode elongation Leaf area index Light intensity Light quality R/FR Light transmission ratio Leaf N concentration
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Assessment of Industrial Land Use Intensity: A Case Study of Beijing Economic-technological Development Area 被引量:3
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作者 HUANG Daquan WAN Wei +1 位作者 DAI Teqi LIANG Jinshe 《Chinese Geographical Science》 SCIE CSCD 2011年第2期222-229,共8页
In recent years, great economic output of land has been achieved in economic-technological development areas in China, but the intensity of land use in some of these areas is very low. The degree of the low intensity ... In recent years, great economic output of land has been achieved in economic-technological development areas in China, but the intensity of land use in some of these areas is very low. The degree of the low intensity of land use needs to be evaluated. The current method of comprehensive evaluation and grading by one index system has the limitations due to the existence of differences between regions and industries. This paper evaluates industrial land use intensity by Total Factor Productivity (TFP) analysis, which not only measures the intensity but also illustrates the ef-ficiency of input factors. This method is applied to the Beijing Economic-technological Development Area (BDA). A comparison analysis on factor use efficiency and input structure of capital and labor between industries is also carried out in the absence of a labor-income ratio. 展开更多
关键词 land use intensity industrial land use Total Factor Productivity (TFP) Beijing Economic-technological Development area (BDA)
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Several Typical Geomechanical Models of Deformation Fracture of Mountain in High Earthquake Intensity Area
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作者 Xiangning Xu,Lansheng Wang 1.Chengdu University of Technology,Chengdu,610059,China. 2.Chengdu Center of Hydrogeology and Engineering Geology of Sichuan Provincial GMR Bureau,Chengdu,610081,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期72-72,共1页
The deformation fracture and stability of mountain under the earthquake action is an important issue that arouses concern of researchers in the field of engineering geology.The authors,from 2000 to 2006, selected the ... The deformation fracture and stability of mountain under the earthquake action is an important issue that arouses concern of researchers in the field of engineering geology.The authors,from 2000 to 2006, selected the 1933 earthquake in Diexi zone as a typical study site to carry out the genetic mechanism research of mountain deformation-fracture caused by earthquake; in order to have comparability,the breadth 展开更多
关键词 HIGH earthquake intensity area DEFORMATION FRACTURE mechanism Geo-mechanical MODEL bedded LANDSLIDE MODEL COLLAPSING MODEL LANDSLIDE MODEL
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Intensity-frequency Estimation Based on Historical Seismic Intensity in the Yunnan Area
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作者 Feng Wei Zhen Meng Liu Qin 《Earthquake Research in China》 CSCD 2017年第3期414-421,共8页
For earthquake disaster mitigation,we use historical records and more complete intensity investigation data from 1500 to 2015 to analyze and estimate the seismic intensity and frequency of the earthquake-prone areas i... For earthquake disaster mitigation,we use historical records and more complete intensity investigation data from 1500 to 2015 to analyze and estimate the seismic intensity and frequency of the earthquake-prone areas in Yunnan. We digitized intensity observations and divided the Yunnan region into cell size of 0. 2°× 0. 2° to calculate the seismic intensity-frequency relationship for each cell. Combined with a repeated cycle of intensity of one hundred years and population economics data in Yunnan,we analyze future areas of concern. The results can provide a reference for earthquake hazardous area zoning.This method is based on historical earthquake data,reducing as much as possible the various hypotheses for the assessment,and thus can concisely reflect the different intensityfrequency distributions of the region. 展开更多
关键词 intensity-frequency SEISMIC intensity YUNNAN area
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A DEM fusion method for ascending and descending orbit StereoSAR DEMs in complicated mountain areas considering SAR echo intensity
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作者 CAI Guo-lin SHEN Dong +2 位作者 ZHANG Ao-li YU Hai-hua ZHANG Xuan-yu 《Journal of Mountain Science》 SCIE CSCD 2021年第1期101-110,共10页
To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysi... To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysis for the influence of terrain features and SAR side-looking imaging characteristics on radar echo intensity and DEM accuracy,four Terras AR-X images with the stripmap mode and the 3 m spatial resolution covering a certain area of Maoxian County,Sichuan Province,China,was selected as the experimental area.StereoSAR technology was used to extract the ascending orbit StereoSAR DEM and the descending orbit StereoSAR DEM,respectively,and the corresponding radar echo intensity map was calculated.Then,while comparing the radar echo intensity corresponding to the same point position,DEM fusion was carried out,and the accuracy of DEM before and after the fusion was analyzed with the ground points measured by GNSS-RTK as reference data.Finally,a high-quality DEM with a 3 m spatial resolution in the experimental area was obtained.The DEM accuracy was improved on all slopes,and the mean absolute deviation(MAD)improved to 4.798 m,the standard deviation(SD)improved to 6.087 m and the LE90 improved to 40.48 m.The experimental results indicate that the fusion method of highresolution ascending and descending orbit StereoSAR DEMs considering SAR echo intensity can effectively extract DEM with high accuracy and reliability,which can provide technical support for obtaining highquality terrain information in similar areas. 展开更多
关键词 Mountain areas StereoSAR Ascending orbits Descending orbits DEM fusion SAR echo intensity
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Regional disparity in the changes of agricultural land use intensity in China during 1980-2002 被引量:16
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作者 LIU Chengwu LI Xiubin 《Journal of Geographical Sciences》 SCIE CSCD 2006年第3期286-292,共7页
Based on the cost-benefit data (1980-2002) of farm products and China Agriculture Yearbooks, this paper studies the regional disparity in the changes of the agricultural land use in China during the period 1980-2002... Based on the cost-benefit data (1980-2002) of farm products and China Agriculture Yearbooks, this paper studies the regional disparity in the changes of the agricultural land use in China during the period 1980-2002 from three aspects such as the degree of intensity, the sown area and the abandoned farmland. The results show that: (1) The degree of intensity of land use in the westena region during 1980-2000 has a strong uptrend, but in the eastern and central regions the degree of intensity descends obviously and has shown a continuous downtrend since 1997. (2) The total sown area shrinks notably in the eastern region, while it enlarges constantly in the western region. (3) The sown area in the eastern, central and western regions has gone through a similar cyclic process: down (1980-1985)-up (1985-1991)-down (1991-1994)-up (1994-1999)-down (1999-2002). However, there are obvious differences in amplitude variation and tendency among them. The sown area has shrunk in the eastern region and expanded in the central and western regions especially before 1999. (4) The most cases of abandoned farmland are reported in the central region, the second in the eastern region and the least in the western region. The abandonment phenomena chiefly occurred during 1992-1995 in the eastern region, and during 1998-2002 in the central region. 展开更多
关键词 China agricultural land use the degree of intensity sown area abandonment of farmland regional disparity
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Monitoring of Respiratory Infections in the Intensive Area of Respiratory System Disease 被引量:1
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作者 Filippo Ricciardiello Maria Cardone +4 位作者 Giuseppe Fiorentino Massimo Mesolella Flavia Oliva Annalisa Pianese Carlo Antonio Leone 《Advances in Microbiology》 2014年第9期560-566,共7页
Respiratory infections are the most frequent nosocomial infections after those urinaries and surgicals. We analysed respiratory infection incidences in patients treated with different kinds of respiratory assistance (... Respiratory infections are the most frequent nosocomial infections after those urinaries and surgicals. We analysed respiratory infection incidences in patients treated with different kinds of respiratory assistance (non-invasive ventilation and invasive mechanical ventilation trough tracheostomy), studying 640 patients recovering in the intensive area of respiratory disease from 2010 to 2013. We had 113 cases of respiratory infections: 42.5% in patients of non-invasive ventilation group and 57.5% of patients treated with invasive ventilation with a statistically significant difference between the two groups. The patients treated with non-invasive ventilation showed a lower incidence of nosocomial respiratory infections. Prevention guidelines are important to reduce nosocomial infections frequency. 展开更多
关键词 intensIVE RESPIRATORY area Multi-Resistant PATHOGENS NOSOCOMIAL INFECTIONS Pneumonias TRACHEOSTOMY
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Discussion on the Index System of Intensive Land Use Evaluation in Development Area 被引量:7
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作者 LIU Xiang-dong1,GAO Jie2 1.School of Land Science and Technology,China University of Geosciences,Beijing 100083,China 2.Weida Real Estate Evaluation Corporation of Henan Province,Luoyang 471000,China 《Asian Agricultural Research》 2011年第2期91-96,100,共7页
The establishment of evaluation index system is the key to the evaluation of intensive land use.On the basis of expounding connotation,characteristics and the principle of establishing evaluation index system,and as f... The establishment of evaluation index system is the key to the evaluation of intensive land use.On the basis of expounding connotation,characteristics and the principle of establishing evaluation index system,and as for the problems existing in Evaluation Regulation(Trial)of Intensive Land Use in Development Area,regarding the evaluation index system of intensive land use in the development area,in the light of the connotation of intensive land use in development area,coupled with the practical situation of the land use in China's development area,after referring to the research achievements of domestic and abroad scholars,some suggestions are put forward in order to improve and perfect the evaluation index system of intensive land us in development area. 展开更多
关键词 intensIVE LAND USE EVALUATION INDEX system Develop
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Experimental Study on Ultrasonic Cavitation Intensity Based on Fluorescence Analysis
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作者 Linzheng Ye Shida Chuai +1 位作者 Xijing Zhu Dong Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期196-204,共9页
The Ultrasonic cavitation effect has been widely used in mechanical engineering,chemical engineering,biomedicine,and many other fields.The quantitative characterization of ultrasonic cavitation intensity has always be... The Ultrasonic cavitation effect has been widely used in mechanical engineering,chemical engineering,biomedicine,and many other fields.The quantitative characterization of ultrasonic cavitation intensity has always been a difficulty.Based on this,a fluorescence analysis method has been adopted to explore ultrasonic cavitation intensity in this paper.In the experiment of fluorescence intensity measurement,terephthalic acid(TA)was used as the fluorescent probe,ultrasonic power,ultrasonic frequency,and irradiation time were independent variables,and fluorescence intensity and fluorescence peak area were used as experimental results.The collapse of cavitation bubble will cause molecular bond breakage and release·OH,and the non-fluorescent substance TA will form the strong fluorescent substance TAOH with·OH.The spectra of the treated samples were measured by a F-7000 fluorescence spectrophotometer.The results showed that the fluorescence intensity and fluorescence peak area increased rapidly after ultrasonic cavitation treatment,and then increased slowly with the increase of ultrasonic power,which gradually increased with the increase of irradiation time.They first decreased and then increased with the increase of ultrasonic frequency from 20 kHz to 40 kHz.The irradiation time was the most influential factor,and the cavitation intensity of low frequency was higher overall.The fluorescence intensity and fluorescence peak area of the samples increased by 2-20 times after ultrasonic treatment,which could increase from 69 and 5238 to 1387 and 95451,respectively.After the irradiation time exceeded 25 min,the growth rate of fluorescence intensity slowed down,which was caused by the decrease of gas content and TA concentration in the solution.The study quantitatively characterized the cavitation intensity,reflecting the advantages of fluorescence analysis,and provided a basis for the further study of ultra-sonic cavitation. 展开更多
关键词 Ultrasonic cavitation Cavitation intensity Fluorescence intensity Fluorescence peak area
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Soil and Water Resources and Land Sustainable Productivity in the Catchment Area with Intensive Management in Hilly Red Soil Regions,China
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作者 HUANGDao-you WANGKe-lin +2 位作者 CHENGui-qiu HUANGMin PENGTing-bo 《Agricultural Sciences in China》 CAS CSCD 2004年第5期356-363,共8页
Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studie... Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studied. Fixed observation results from 1993to 2002 showed that pools covering about 15% of total area could store up 10% of surfacerunoff, keep 78.1% of eroded soil and 65.4% of lost nutrients. The yearly ratio ofinterception and evapotranspiration in land, storage in pools and drainage was 7:2:1,which ensured the resources and nutrients equilibrium and a benign recycle in thecatchment area system, and benefited the aquatic culture and helped to resist seasonaldrought. Moreover, the results showed that soil erosion modulus decreased significantly,equal to or lower than soil loss tolerance (≤500 tkm-2) in reddish yellow soil regions.Soil organic matter, total and available N content in sloping land, dryland and paddyfield increased steadily (>10%); water storage enhanced by more than 20% in sloping landand dryland in drought season; crop production increased by more than 20%; and productionof trees, fruits, tea and fish as well as land productivity increased yearly. 展开更多
关键词 Catchment area with intensive management Soil and water resources Soil fertility Land sustainable productivity Hilly red soil region
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Database Management System Construction for the Evaluation Results of Intensive Land Use in the Development Areas of Hunan Province 被引量:1
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作者 Mingliang LIU 《Asian Agricultural Research》 2013年第12期54-58,共5页
Using spatial data integration and database technology,analyzing and integrating the assessment results in all the development zones at different time in Hunan Province,the paper is intended to construct the database ... Using spatial data integration and database technology,analyzing and integrating the assessment results in all the development zones at different time in Hunan Province,the paper is intended to construct the database and managerial system for the assessment results of land use intensity in development zones,thus formulating"one map"of Hunan Development zones and realizing the integrated management and application of the assessment results in all the development zones at any time of Hunan above the provincial level.It has been proved that the system has good application effect and promising development in land management for land management departments and development zones. 展开更多
关键词 SPATIAL DATA INTEGRATION EVALUATION of intensIVE l
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Urban growth scenario projection using heuristic cellular automata in arid areas considering the drought impact
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作者 TANG Xiaoyan FENG Yongjiu +7 位作者 LEI Zhenkun CHEN Shurui WANG Jiafeng WANG Rong TANG Panli WANG Mian JIN Yanmin TONG Xiaohua 《Journal of Arid Land》 SCIE CSCD 2024年第4期580-601,共22页
Arid areas with low precipitation and sparse vegetation typically yield compact urban pattern,and drought directly impacts urban site selection,growth processes,and future scenarios.Spatial simulation and projection b... Arid areas with low precipitation and sparse vegetation typically yield compact urban pattern,and drought directly impacts urban site selection,growth processes,and future scenarios.Spatial simulation and projection based on cellular automata(CA)models is important to achieve sustainable urban development in arid areas.We developed a new CA model using bat algorithm(BA)named bat algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model by considering drought constraint to accurately delineate urban growth patterns and project future scenarios of Urumqi City and its surrounding areas,located in Xinjiang Uygur Autonomous Region,China.We calibrated the BA-POO-CA model for the drought-prone study area with 2000 and 2010 data and validated the model with 2010 and 2020 data,and finally projected its urban scenarios in 2030.The results showed that BA-POO-CA model yielded overall accuracy of 97.70%and figure-of-merits(FOMs)of 35.50%in 2010,and 97.70%and 26.70%in 2020,respectively.The inclusion of drought intensity factor improved the performance of BA-POO-CA model in terms of FOMs,with increases of 5.50%in 2010 and 7.90%in 2020 than the model excluding drought intensity factor.This suggested that the urban growth of Urumqi City was affected by drought,and therefore taking drought intensity factor into account would contribute to simulation accuracy.The BA-POO-CA model including drought intensity factor was used to project two possible scenarios(i.e.,business-as-usual(BAU)scenario and ecological scenario)in 2030.In the BAU scenario,the urban growth dominated mainly in urban fringe areas,especially in the northern part of Toutunhe District,Xinshi District,and Midong District.Using exceptional and extreme drought areas as a spatial constraint,the urban growth was mainly concentrated in the"main urban areas-Changji-Hutubi"corridor urban pattern in the ecological scenario.The results of this research can help to adjust urban planning and development policies.Our model is readily applicable to simulating urban growth and future scenarios in global arid areas such as Northwest China and Africa. 展开更多
关键词 bat algorithm cellular automata(CA) probability-of-occurrence drought intensity algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model arid areas
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Analysis on Spatio-temporal Distribution of Lightning in Dalian Area of China between 2007 and 2008 被引量:2
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作者 黄振 李万彪 《Meteorological and Environmental Research》 CAS 2010年第1期14-17,29,共5页
The cloud-to-ground lightning data between 2007 and 2008 were collected by lightning detection and location system,which was composed of four lightning detectors in four different sites of Dalian area.The spatio-tempo... The cloud-to-ground lightning data between 2007 and 2008 were collected by lightning detection and location system,which was composed of four lightning detectors in four different sites of Dalian area.The spatio-temporal distribution of cloud-to-ground lightning in surrounding areas of Dalian was analyzed from several aspects of polarity distribution,diurnal variation,lightning intensity and lightning density.The results showed that the number of negative lightning accounted for 93.9% of the total number of lightning,and its average lightning intensity was 27.99 kA.The number of positive lightning accounted for 6.1% of the total number of lightning,and its average lightning intensity was 35.56 kA.The diurnal variation of lightning frequency showed an obvious structure of two peaks (17:00-18:00 and 04:00-05:00) and two valleys (09:00-10:00 and 00:00-01:00).The number of lightning between May and September was 91.5% of the annual number,and the lightning occurred the most frequently between June and August.Most of positive and negative lightning was at the intensity of 15-35 kA,80.0% lower than 40 kA,and 99.3% lower than 100 kA.The lightning density had obvious regional differences in distribution,high in the Liaodong Bay and the Dalian Bay and low in inland areas.Therefore,coastal areas should attract more attention in lightning disaster defense in the surrounding areas of Dalian. 展开更多
关键词 Dalian area Lightning intensity Spatio-temporal distribution China
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广州市降雨强度和汇水面积对降雨径流污染的影响
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作者 刘柏佑 仲崇军 +2 位作者 曹勇锋 叶晓妍 荣宏伟 《环境污染与防治》 北大核心 2025年第1期72-76,共5页
随着城市点源污染得到有效解决,降雨径流产生的面源污染逐渐成为城市水环境的主要污染源。利用Infoworks ICM软件构建广州市猎德涌流域排水系统的水力水质模型,系统分析了降雨强度和汇水面积对降雨径流污染的影响。结果表明,当最大降雨... 随着城市点源污染得到有效解决,降雨径流产生的面源污染逐渐成为城市水环境的主要污染源。利用Infoworks ICM软件构建广州市猎德涌流域排水系统的水力水质模型,系统分析了降雨强度和汇水面积对降雨径流污染的影响。结果表明,当最大降雨强度达到50 mm/h时,初雨径流污染达到峰值;当汇水面积小于100 hm^(2)时,管渠排放具有明显初雨效应,当汇水面积超过100 hm^(2)后,初雨效应会逐渐削弱。通过定量化表征降雨强度、汇水面积与降雨径流污染的关系,为城市雨水处理设施布设和面源污染治理提供参考。 展开更多
关键词 径流污染 汇水面积 降雨强度 水力水质模型 Infoworks ICM
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基于机器学习的极震区烈度快速预测方法
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作者 王茂岑 张令心 +2 位作者 钟江荣 张云霞 张鹏 《振动与冲击》 北大核心 2025年第2期235-244,共10页
极震区烈度的快速准确评估对于震后的应急响应至关重要。针对现有的极震区烈度预测精度差的问题,首先,整理了1949年—2021年的406次震级大于5.0且极震区烈度大于Ⅴ度的历史震例;然后,基于输入参数可在震后快速易于获取的原则,选择震级... 极震区烈度的快速准确评估对于震后的应急响应至关重要。针对现有的极震区烈度预测精度差的问题,首先,整理了1949年—2021年的406次震级大于5.0且极震区烈度大于Ⅴ度的历史震例;然后,基于输入参数可在震后快速易于获取的原则,选择震级和震源深度作为输入参数,分别建立了基于随机森林、k近邻、逻辑回归以及决策树4种机器学习模型的极震区烈度快速预测方法;最后,对这几种方法的性能进行比较,并与已有的统计回归方法进行对比。结果显示:基于随机森林模型的预测方法性能更好,预测的准确率也很高;与仅选用震级作为输入参数的预测方法相比,该方法的准确率得到了较大提高;与现有的统计回归方法相比,该方法在准确率上有明显优越性。 展开更多
关键词 震级 震源深度 极震区烈度 机器学习 快速预测方法
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山西省高烈度区砖混结构地震易损性分析
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作者 任瑞国 曾金艳 +2 位作者 李宏伟 郝雪景 王雷雷 《世界地震工程》 北大核心 2025年第1期154-164,共11页
针对山西省地震灾害风险评估的本地化需求,基于房屋建筑现场抽样详查获取的砖混结构数据,开展了基本烈度为高烈度区域内不同地市的地震易损性分析,建立了适用于山西省九个地市的城市多层砖混和农村砖混结构房屋的地震易损性模型。在此... 针对山西省地震灾害风险评估的本地化需求,基于房屋建筑现场抽样详查获取的砖混结构数据,开展了基本烈度为高烈度区域内不同地市的地震易损性分析,建立了适用于山西省九个地市的城市多层砖混和农村砖混结构房屋的地震易损性模型。在此基础上,采用平均震害指数和损失期望作为区域抗震能力的评估指标,分析了这些地区的砖混结构的抗震能力。研究结果表明:山西省高烈度区的农村砖混结构与国家标准下的未设防砖混结构具备相近的抗震能力;而大同、临汾和晋中三个地市的城市砖混结构则表现出相对较弱的抗震能力。研究成果可为山西省高烈度区砖混结构的地震灾害风险评估与防范提供了重要的参考依据。 展开更多
关键词 山西省高烈度区 砖混结构 地震易损性 平均震害指数 损失期望
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大连港大窑湾港区北岸集装箱码头方案优化
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作者 薛天寒 李蕊 +3 位作者 徐杏 扬懿 王达川 房卓 《水运工程》 2025年第1期37-43,共7页
大窑湾港区是大连港的核心港区,其南岸已经建成规模化集装箱码头区,北岸尚未开发,是辽宁沿海港口最重要的外贸集装箱储备港口资源。严控围填海政策实施以来,集装箱码头规划建设的外部约束更为复杂。以大连港大窑湾港区北岸作业区为例,... 大窑湾港区是大连港的核心港区,其南岸已经建成规模化集装箱码头区,北岸尚未开发,是辽宁沿海港口最重要的外贸集装箱储备港口资源。严控围填海政策实施以来,集装箱码头规划建设的外部约束更为复杂。以大连港大窑湾港区北岸作业区为例,探讨资源环境约束下集装箱港口集约化规划方法,研究岸线和陆域资源优化使用,对陆域功能空间需求进行量化和精细化布置,基于模型分析和规模测算,提出岸线和陆域布置优化方案。研究表明,按照“运输需求-用地需求-平面方案”的论证过程,通过“大顺岸、连片式”的平面布置和“码头生产区+综合物流园区”的功能布局,能够有效加强需求和方案的匹配度,在保证码头通过能力发挥的同时,节约集约用海用地,实现港口与资源环境协调发展。 展开更多
关键词 集装箱码头 规划方案 集约化规划 大窑湾港区
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寒地城市滨水区建筑高度和密度对水体降温效应的影响
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作者 林晔 纪旭 +1 位作者 袁敬诚 安天一 《沈阳建筑大学学报(自然科学版)》 北大核心 2025年第1期113-120,共8页
探究水体周边区域的建筑密度、建筑高度对水体降温效应的影响,为减缓城市热岛效应提供技术支持。基于Landsat8及Sentinel-2遥感影像数据,选取2020年夏季沈阳市三环内的浑河及其周边特定区域作为研究对象,借助一河两岸类型划分法划分三... 探究水体周边区域的建筑密度、建筑高度对水体降温效应的影响,为减缓城市热岛效应提供技术支持。基于Landsat8及Sentinel-2遥感影像数据,选取2020年夏季沈阳市三环内的浑河及其周边特定区域作为研究对象,借助一河两岸类型划分法划分三环内的浑河滨水区,并利用ArcGIS软件计算研究区的建筑密度和建筑高度;依据建筑参数和区域划分结果,构建多环缓冲区,计算浑河的降温效应;借助相关性分析,探讨浑河降温强度、各分区的平均地表温度与建筑密度、建筑高度之间的关联。建筑密度与滨水区地表温度呈线性正相关,与降温强度呈线性负相关;建筑高度与滨水区地表温度的相关性较弱,与降温强度呈非线性相关;密集高层建筑群离水体越远,水体降温效果越好。浑河的水体降温效应距离最远可达1.2 km;建筑密度小于0.2,建筑高度低于12.7 m时,水体降温效果较为显著。 展开更多
关键词 热环境 滨水区 降温强度 建筑密度 建筑高度 多环缓冲分区
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高烈度区某凸出地形下建筑隔震分析与设计
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作者 郝俊猛 张锐 陆楷 《建筑技术》 2025年第1期112-116,共5页
以云南省泸水市某中小学教学楼项目为研究对象,采用YJK和ETABS结构分析软件对位于高烈度区域局部凸出地形下的坡地建筑进行隔震时程分析和设计,与YJK非隔震模型计算结果进行对比分析,采用隔震技术对高烈度下重点设防类的建筑可显著延长... 以云南省泸水市某中小学教学楼项目为研究对象,采用YJK和ETABS结构分析软件对位于高烈度区域局部凸出地形下的坡地建筑进行隔震时程分析和设计,与YJK非隔震模型计算结果进行对比分析,采用隔震技术对高烈度下重点设防类的建筑可显著延长结构本身周期,降低层间剪力及底部剪力,有效减弱水平地震作用,对该类型建筑具有较好的减震控制效果。研究以实际工程为例,介绍了隔震设计步骤与流程,合理考虑局部凸出地形对地震作用影响,对该隔震建筑在设防地震、罕遇地震下进行时程分析和验算,为隔震技术在高烈度区域局部凸出地形下设计研究和应用提供参考。 展开更多
关键词 隔震设计 高烈度区 凸出地形 ETABS 时程分析
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