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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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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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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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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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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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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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Direct measurement of the three-dimensional distribution of leaf area density and light conditions in a mature oak stand by the cube method
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作者 Chiharu Migita Yukihiro Chiba Tanaka Kenzo 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1817-1827,共11页
Although the distributions of foliage and light play major roles in various forest functions,accurate,nondestructive measurement of these distributions is difficult due to the complexity of the canopy structure.To eva... Although the distributions of foliage and light play major roles in various forest functions,accurate,nondestructive measurement of these distributions is difficult due to the complexity of the canopy structure.To evaluate the foliage and light distributions directly and nondestructively in a mature oak stand,we used the cube method by dividing the forest canopy into small cubes(50 cm per side)and directly measured leaf area density(LAD,the total one-sided leaf area per unit volume,i.e.,cube)and relative irradiance(RI)within each cube.The distribution of LAD and of RI was highly heterogeneous,even at the same canopy height.This heterogeneity reflected the presence of foliage clusters associated with multiple forking branches.The relationship between cumulative LAD at the canopy surface and average RI followed the Beer-Lambert law.The mean light extinction coefficient(K)was 0.32.However,K was overestimated by more than double(0.80)when calculated based on the classical method using RI at the forest floor.This overestimation was caused by the lower RI due to light absorption by nonleaf plant parts below the canopy.Our findings on the complex foliage and light distributions in canopy layers should help improve the accuracy of RI and K measurements and thus more accurate predictions of environmental responses and forest functions. 展开更多
关键词 Beer-Lambert law Canopy structure Foliage cluster Leaf area density Leaf area index Relative light intensity
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我国黄土高原地区地震动衰减关系研究的若干进展 被引量:1
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作者 薄景山 万卫 +2 位作者 彭达 段玉石 李琪 《地震工程学报》 CSCD 北大核心 2024年第1期182-198,共17页
地震动的衰减关系是指地震动随震级、距离和场地条件等变化的经验关系,近年来在我国亦被称为地震动预测方程,是估计地震动及其影响场的主要方法之一,在地震区划和重大工程场地地震安全性评价中被广泛应用。黄土是一种特殊土,在我国广泛... 地震动的衰减关系是指地震动随震级、距离和场地条件等变化的经验关系,近年来在我国亦被称为地震动预测方程,是估计地震动及其影响场的主要方法之一,在地震区划和重大工程场地地震安全性评价中被广泛应用。黄土是一种特殊土,在我国广泛分布。我国黄土高原地区地质构造复杂,新构造活动强烈,中强地震频发,地震动的衰减关系有其特殊性,总结我国黄土高原地区地震动衰减关系的研究成果对促进黄土高原地区抗震研究有重要意义。在简要介绍国内外地震动衰减关系研究的基础上,全面系统地总结我国学者在黄土高原地区的地震烈度衰减关系,基岩和土层场地地震动峰值加速度、峰值速度、峰值位移以及反应谱衰减关系方面的研究成果;评述和讨论在黄土覆盖地区地震动衰减研究领域存在的问题和今后的研究方向。文章的研究工作对从事黄土高原地区地震工程研究的科技人员有重要参考价值。 展开更多
关键词 黄土高原地区 地震烈度 地震动 衰减关系 基岩 土层 研究进展
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海域地震动强度包络模型研究
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作者 张超 陈昽 +3 位作者 武程 杜修力 赖志超 王丕光 《防灾减灾工程学报》 CSCD 北大核心 2024年第3期506-517,共12页
人工模拟地震动是目前开展海洋工程结构抗震分析的主要地震输入分析。强度包络函数是人工模拟地震动的重要参数,决定了地震动的强度非平稳性特性,并对地震动持时起控制作用。目前的地震动强度包络模型均是基于陆域地震动记录统计分析得... 人工模拟地震动是目前开展海洋工程结构抗震分析的主要地震输入分析。强度包络函数是人工模拟地震动的重要参数,决定了地震动的强度非平稳性特性,并对地震动持时起控制作用。目前的地震动强度包络模型均是基于陆域地震动记录统计分析得出,无法准确反应海域地震动的强度特性。因此,基于日本K-Net强震动观测台网的实测地震数据库,分析海域地震动在时域中强度分布特性;提出适用于海域地震动的三段式强度包络模型,回归得到震级M、震中距R及关键参数上升段t_(1)、强震平稳段ts、下降段衰减率c(无量纲)的计算表达式;研究震级、震中距对海域地震动强度包络模型的影响规律,并探讨海域地震动与陆域地震动强度包络模型的异同。研究结果表明:海域地震动强度包络模型中关键参数上升段t_(1)、强震平稳段ts、下降段衰减率c的取值范围分别为[13~52 s],[12~79 s],[0.037~0.173];震级对关键参数(t_(1)、t_(s)、c)的影响要大于震中距;与陆域地震动相比,海域地震动的强度包络模型的下降段衰减率c相差显著,且各关键参数的分布范围更大。 展开更多
关键词 海域地震动 强度包络模型 衰减关系 三段式模型 相模湾地区
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基于AAA算法的三种调强方式在宫颈癌放射治疗中的剂量学比较
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作者 韩超 陈晶晶 +1 位作者 陈宏林 苗慧 《医疗装备》 2024年第1期14-17,共4页
目的比较宫颈癌术后放射治疗中容积旋转调强(RA)、动态调强(SW)、动态调强固定钨门(FJ)技术3种调强方式的剂量学差异。方法选取2023年1-5月于徐州市肿瘤医院接受宫颈癌术后放射治疗的30例患者,使用Eclipse 13.5治疗计划系统(调用AAA算... 目的比较宫颈癌术后放射治疗中容积旋转调强(RA)、动态调强(SW)、动态调强固定钨门(FJ)技术3种调强方式的剂量学差异。方法选取2023年1-5月于徐州市肿瘤医院接受宫颈癌术后放射治疗的30例患者,使用Eclipse 13.5治疗计划系统(调用AAA算法),对所有患者分别设计RA、SW、FJ 3种调强方式的放射治疗计划。根据剂量体积直方图(DVH)比较计划靶区(PTV)平均剂量(Dmean)、靶区适形指数(CI)、均匀指数(HI)及危及器官(OARs)脊髓、直肠、股骨头等的受照射剂量,并比较加速器跳数(MU)及低剂量区指数(LDAI)。结果3种调强方式PTV的Dmean比较,差异无统计学意义(P>0.05);靶区CI、HI、直肠V40、膀胱V40、加速器MU方面RA技术优势明显。小肠V40、双侧股骨头的最大剂量(Dmax)、低剂量区指数(LDAI),RA表现不如SW和FJ,差异有统计学意义(P<0.05)。结论RA可以明显缩短治疗时间,提高治疗效率,且靶区适形度和均匀性更好,但对膀胱、直肠和小肠的高剂量控制不如SW和FJ,因此推荐在宫颈癌放射治疗计划设计中优先考虑使用RA调强方式。 展开更多
关键词 宫颈癌 调强放射治疗 剂量学 低剂量区指数
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中国陆上风电开发土地需求的定量研究
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作者 张力小 陈云钊 +3 位作者 张鹏鹏 李雨芩 武子凡 杨娜 《中国人口·资源与环境》 CSSCI CSCD 北大核心 2024年第5期46-57,共12页
随着气候变化、能源短缺等问题的日益突出,大规模开发可再生清洁能源已成为世界各国的普遍选择。其中,陆上风电以其技术成熟、安全高效的优势,在全球能源转型的进程中发挥着重要作用。然而,风能资源具有能量密度低、不稳定和空间分散等... 随着气候变化、能源短缺等问题的日益突出,大规模开发可再生清洁能源已成为世界各国的普遍选择。其中,陆上风电以其技术成熟、安全高效的优势,在全球能源转型的进程中发挥着重要作用。然而,风能资源具有能量密度低、不稳定和空间分散等特点,大规模开发陆上风电需要大量土地资源支撑。为保障碳中和目标下风电发展的土地资源需求,该研究对中国陆上风电的土地占用情况进行了定量研究。首先,以排他性为界定标准,从时空维度重新划分了风电场土地占用类型。其次,融合样本参数法和α形状算法,分类核算了中国现有陆上风电场的占地面积。最后,综合考虑风电技术发展趋势,系统模拟预测了碳中和目标下不同发展情景的中国风电用地需求。结果表明:①基于排他性原则,风电场总占地面积在空间维度上可分为直接影响区域和间接影响区域两部分;直接影响区域在时间维度上可分为永久用地和临时用地两部分。②2022年中国陆上风电场风机基础占地、永久用地、临时用地和直接影响区域占地面积分别达到48.28 km^(2)、352.08 km^(2)、1234.86 km^(2)和1638.81 km^(2)。③2022年中国陆上风电场间接影响区域占地面积和总占地面积分别达到了9.81×10^(4)km^(2)和9.99×10^(4)km^(2),总占地面积几乎与全国城镇总用地面积相当。④与当前技术水平情景相比,技术进步与风机换代情景下,2060年中国风电各类用地需求均有大幅下降,且用地需求在2050年前后达到峰值,风电机组的大型化替代对土地资源的节约潜力巨大。因此,完善风电建设用地标准、提升风电开发用地效率、统筹推进海上风电建设,是协同风能资源开发与土地资源可持续利用的重要路径。 展开更多
关键词 风电场 排他性 用地强度 面积核算 土地需求
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塔里木盆地哈拉哈塘—哈得地区中生界物源转换及沉积充填响应
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作者 易珍丽 石放 +5 位作者 尹太举 李斌 李猛 刘柳 王铸坤 余烨 《岩性油气藏》 CAS CSCD 北大核心 2024年第5期56-66,共11页
通过矿物成分分析、砂地比计算、地震属性分析及测井响应特征识别等技术手段,对塔里木盆地哈拉哈塘—哈得地区中生界典型沉积时期的古地貌形态、沉积体系展布、地层及砂体发育特征等进行了研究。研究结果表明:(1)塔里木盆地哈拉哈塘—... 通过矿物成分分析、砂地比计算、地震属性分析及测井响应特征识别等技术手段,对塔里木盆地哈拉哈塘—哈得地区中生界典型沉积时期的古地貌形态、沉积体系展布、地层及砂体发育特征等进行了研究。研究结果表明:(1)塔里木盆地哈拉哈塘—哈得地区三叠系物源主要来自东北部的天山造山带,其ZTR系数由东北部向凹陷中央逐渐增大;侏罗系和白垩系物源主要来自东南部和南部的昆仑山造山带,其ZTR系数由北部、南部向凹陷中央逐渐增大。(2)三叠纪晚期,随着古特提斯洋的增生,研究区北部天山的隆升强度减弱与南部昆仑山的隆升强度增大是此次物源转换的主要原因。(3)三叠纪,研究区的沉降-沉积中心位于南部,主要发育了一套北东—南西向的辫状河三角洲—深水湖泊沉积;侏罗纪和白垩纪,沉降-沉积中心则跃迁到研究区北部,主要发育了一套南东—北西向和南—北向的辫状河三角洲—浅水湖泊沉积。(4)三叠纪,砂体叠置样式的前积方向主要为北东—南西方向;侏罗纪和白垩纪,砂体叠置样式的前积方向主要为南东—北西方向和南—北方向。(5)三叠系岩性油气藏主要发育于研究区西南部,侏罗系和白垩系岩性油气藏主要发育于研究区西北部和北部。 展开更多
关键词 物源转换 沉积充填-叠置样式 地震属性 重矿物ZTR系数 隆升强度 岩性油气藏 中生界 哈拉哈塘—哈得地区 塔里木盆地
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集约用地视角下生态敏感区村庄用地更新研究——以北海大健康生态新区为例
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作者 张春阳 王子豪 +1 位作者 王成芳 吴子超 《小城镇建设》 2024年第8期41-50,共10页
在我国土地资源稀缺、大量空间需求矛盾及大力实施乡村振兴战略的背景下,村庄用地更新成为获取建设空间增量的有效手段,尤其是生态敏感区内的村庄,建设用地的合理布局对于区域生态系统与人类活动之间的平衡具有重要意义。文章以广西壮... 在我国土地资源稀缺、大量空间需求矛盾及大力实施乡村振兴战略的背景下,村庄用地更新成为获取建设空间增量的有效手段,尤其是生态敏感区内的村庄,建设用地的合理布局对于区域生态系统与人类活动之间的平衡具有重要意义。文章以广西壮族自治区北海市大健康生态新区的规划实践为例,探讨集约用地理念下的生态敏感区村庄用地更新方法,首先对现状生态环境和用地布局进行解译,归纳其生态基底特征、用地布局形式与实践难题;其次提出集约用地布局策略,包括确定建设用地及空间管制分区、制定生态保护与安全韧性策略、解译并延续现状肌理与用地模式、植入功能业态与风貌协调,以期为生态敏感区的村庄用地更新实践提供参考。 展开更多
关键词 集约用地 生态敏感区 村庄用地更新 用地布局 北海市
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