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改善高层建筑适居性的设计策略研究 被引量:3
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作者 付本臣 张珊珊 《哈尔滨建筑大学学报》 北大核心 2002年第3期96-100,共5页
首先阐释了高层建筑和适居性的概念,剖析了高层建筑的聚居特性:远地而居的本体特性、袋形封闭的结构特性、大容量、高密度的规模特性以及泛及城市的关联特性,在此基础上梳理其适居缺陷,将它概括为安全性、健康性、舒适性和意义性四个层... 首先阐释了高层建筑和适居性的概念,剖析了高层建筑的聚居特性:远地而居的本体特性、袋形封闭的结构特性、大容量、高密度的规模特性以及泛及城市的关联特性,在此基础上梳理其适居缺陷,将它概括为安全性、健康性、舒适性和意义性四个层面的问题,并有针对性地提出了改善高层建筑适居性的设计策略:引入类地系统、营造生态环境、建立开放结构和尝试巨型开发. 展开更多
关键词 设计 高层建筑 适居性 聚居环境 类地系统 生态设计
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Application of GIS in Ecological Land Type(ELT)mapping--A case in Changbai Mountain area 被引量:2
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作者 肖宝英 代力民 +1 位作者 陈高 邵国凡 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期56-60,84,共5页
This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin Province), and expatiates the definition, basic characters and its development of Ecological L... This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin Province), and expatiates the definition, basic characters and its development of Ecological Land Classification (ELC). Based on the combination of relief map, satellite photography for study area and vegetation inventory data of 480 sample sites, a 5-class and a 15-class ecological land type map was concluded according to 4 important factors including slope, aspect, vegetation and elevation. Ecological Classification System (ECS) is a method to identify, characterize, and map ecosystems. The Ecological Land Type (ELT) was examined and applied initially in eastern Jilin Province. 展开更多
关键词 Ecological Land Type(ELT) Ecological Classification System(ECS) Ecological land classification(ELC) Geographic Information system(GIS)
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GIS-Based Red Soil Resources Classification andEvaluation 被引量:24
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作者 HUYUEMING WANGRENCHAO 《Pedosphere》 SCIE CAS CSCD 1999年第2期131-138,共8页
A small scale red soil resources information system (RSRIS) with applied mathematical models wasdeveloped and applied in red soil resources (RSR) classification and evaluation, taking Zhejiang Province,a typical distr... A small scale red soil resources information system (RSRIS) with applied mathematical models wasdeveloped and applied in red soil resources (RSR) classification and evaluation, taking Zhejiang Province,a typical distribution area of red soil, as the study area. Computer-aided overlay was conducted to classifyRSR types. The evaluation was carried out by using three methods, i.e., index summation, square root ofindex multiplication and fuzzy comprehensive assessment, with almost identical results. The result of indexsummation could represent the basic qualitative condition of RSR, that of square root of index multiplicationreflected the real condition of RSR qualitative rank, while fuzzy comprehensive assessment could satisfactorilyhandle the relationship between the evaluation factors and the qualitative rank of RSR, and therefore it is afeasible method for RSR evaluation. 展开更多
关键词 CLASSIFICATION evaluation geographic system (GIS) red soil
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Assessment of Soil Organic Carbon Stock in the Upper Yangtze River Basin 被引量:2
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作者 WANG Xiao-guo ZHU Bo +3 位作者 HUA Ke-ke LUO Yong ZHANG Jian ZHANG An-bang 《Journal of Mountain Science》 SCIE CSCD 2013年第5期866-872,共7页
Soil organic carbon is of great importance to terrestrial ecosystems. Studies on the amount and spatial distribution of soil organic carbon stock in various types of soil can help to better understand the role of soil... Soil organic carbon is of great importance to terrestrial ecosystems. Studies on the amount and spatial distribution of soil organic carbon stock in various types of soil can help to better understand the role of soil in the global carbon cycle and provide a scientific basis for the assessment of the magnitude of carbon stored in a given area. Here we present estimates of soil organic carbon stock in soils in the upper reaches of the Yangtze River based on soil types as defined by Chinese Soil Taxonomy and recently compiled into a digital soil database. The results showed that the total soil organic carbon stock of the upper Yangtze River to a depth of 100 cm was 1.452x1013 kg. The highest soil organic carbon stock was found in felty soils (2.419x10TM kg), followed by dark brown soils (1.269x10=kg), and dark feltysoils (L139x10=kg). Chernozems and irrigation silting soils showed the lowest soil organic carbon stock, mainly due to the small total area of such soils. The soil organic carbon density of these major soil types ranged from 5.6 to 26.1 kg m2- The average soil organic carbon density of the upper reaches of the Yangtze River was 16.4 kg m-2, which was higher than that of the national average. Soil organic carbon density indicated a distinct decreasing trend from west to east, which corresponds to the pattern of increasing temperature from cold to subtropical. 展开更多
关键词 SOIL Organic carbon Carbon stock YangtzeRiver
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Human Settlement Evaluation in Mountain Areas Based on Remote Sensing,GIS and Ecological Niche Modeling 被引量:7
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作者 ZHAO Jian XU Min +1 位作者 LU Shi-lei CAO Chun-xiang 《Journal of Mountain Science》 SCIE CSCD 2013年第3期378-387,共10页
The Qinghai-Tibet Plateau is the word's highest and largest plateau. Due to increasing demands for environment exploration and tourism, a large transitional area is required for altitude adaptation. Hehuang valley, w... The Qinghai-Tibet Plateau is the word's highest and largest plateau. Due to increasing demands for environment exploration and tourism, a large transitional area is required for altitude adaptation. Hehuang valley, which locates in the transition zone between the Loess Plateau and the Qinghai-Tibet Plateau, has convenient transportation and relatively low elevation. Our question is whether the geographic conditions here are appropriate for adapted stay before going into the Qinghai-Tibet Plateau. Therefore, in this study, we examined the potential use of ecological niche modeling (ENM) for mapping current and potential distribution patterns of human settlements. We chose the Maximum Entropy Method (Maxent), an ENM which integrates climate, remote sensing and geographical data, to model distributions and assess land suitability for transition areas. After preprocessing and selection, the correlation between variables and spatial auto- correlation input data were removed and 106 occurrence points and 9 environmental layers were determined as the model inputs. The threshold- independent model performance was reasonable according to lO times model running, with the area under the curve (AUC) values being 0.917± 0.01, and 0.923±0.002 for test data. Cohen's kappa coefficient of model performance was 0.848. Results showed that 82.22% of the study extent was not suitable for human settlement. Of the remaining areas, highly suitable areas aceounted for 1.19%, moderately for 5.3% and marginally for 11.28%. These suitable areas totaled 418.79 km2, and 86.25% of the sample data was identified in the different gradient of suitable area.The decisive environmental factors were slope and two climate variables: mean diurnal temperature range and temperature seasonality. Our model showed a good performance in mapping and assessing human settlements. This study provides the first predicted potential habitat distribution map for human settlement in Ledu County, which could also help in land use management. 展开更多
关键词 Human settlement Remote sensing Suitability assessment Ecological niche modeling
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A SPATIAL CLUSTER METHOD SUPPORTED BY GIS FOR URBAN-SUBURBAN-RURAL CLASSIFICATION 被引量:4
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作者 ZHOUDe-min XUJian-chun +1 位作者 JohnRADKE MULan 《Chinese Geographical Science》 SCIE CSCD 2004年第4期337-342,共6页
This study was undertaken to construct a preliminary spatial analysis method for building an urban-suburban-rural category in the specific sample area of central California and providing distribution characteristics i... This study was undertaken to construct a preliminary spatial analysis method for building an urban-suburban-rural category in the specific sample area of central California and providing distribution characteristics in each category, based on which, some further studies such as regional manners of residential wood burning emission (PM2.5, the term used for a mixture of solid particles and liquid droplets found in the air, refers to particulate matter that is 2.5 mu m or smaller in size) could be carried out for the project of residential wood combustion. Demographic and infrastructure data with spatial characteristics were processed by integrating both Geographic Information System (GIS) and statistics method (Cluster Analysis), and then output to a category map as the result. It approached the quantitative and multi-variables description on the major characteristics variations among the urban, suburban and rural; and perfected the TIGER's urban-rural classification scheme by adding suburban category. Based on the free public GIS data, the spatial analysis method provides an easy and ideal tool for geographic researchers, environmental planners, urban/regional planners and administrators to delineate different categories of regional function on the specific locations and dig out spatial distribution information they wanted. Furthermore, it allows for future adjustment on some parameters as the spatial analysis method is implemented in the different regions or various eco-social models. 展开更多
关键词 GIS cluster analysis PM2.5 census tract urban-suburban-rural classification
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Study of Fussy Clustering of Engineering Geological Environment with GIS 被引量:2
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作者 刘振华 姜振泉 左如松 《Journal of China University of Mining and Technology》 2003年第2期196-200,共5页
Based on previous evaluating methods, a new method which combines GIS with Fussy Clustering algorithm is proposed and applied in evaluating the engineering geological environment of the research area of XuZHou City in... Based on previous evaluating methods, a new method which combines GIS with Fussy Clustering algorithm is proposed and applied in evaluating the engineering geological environment of the research area of XuZHou City in this paper. By analyzing the characteristics and formation of engineering geological environment,the major problems are discussed, including stability of basement rock, sandy soil liquefaction and cultural stratum.According to effecting factors of these problems, the stability of every engineering geological problem in the worked area is classified into different classes. Then, the Fussy Clustering method is used in assessing all conditions of engineering geological environment. Finally, the evaluation is fulfilled in the whole studied area. The calculating result shows the method is feasible. 展开更多
关键词 GIS software i Fussy clustering engineering geological environment
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Avian orientation: multi-cue integration and calibration of compass systems
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作者 刘小峰 尼基塔.切尼佐夫 《Chinese Birds》 2012年第1期1-8,共8页
Migratory birds are known to use a number of different orientation cues to determine and maintain the direction of their movements. They are able to use at least three different sources of compass information, includi... Migratory birds are known to use a number of different orientation cues to determine and maintain the direction of their movements. They are able to use at least three different sources of compass information, including solar, stellar and geomagnetic cues. However, little is known about how these cues are calibrated into uniform reference direction information, while the hierarchy of these cues remains controversial. In recent studies, researchers suggest that avian migrants calibrate their geomagnetic compass on sunset cues, whereas others fail to find such patterns and insist on the prevalence of the magnetic compass. We carefully reviewed the existing literature and suggest that the conflicting results reported by different authors are due to genuine variation among species and propose hypotheses to explain this variation. 展开更多
关键词 BIRDS ORIENTATION compass system geomagnetic field solar cues
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Monitoring urban land cover and vegetation change by multi-temporal remote sensing information 被引量:10
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作者 DU Peijun LI Xingli +2 位作者 CAO Wen LUO Yan ZHANG Huapeng 《Mining Science and Technology》 EI CAS 2010年第6期922-932,共11页
In order to analyze changes in human settlement in Xuzhou city during the past 20 years, changes in land cover and vegetation were investigated based on multi-temporal remote sensing Landsat TM images. We developed a ... In order to analyze changes in human settlement in Xuzhou city during the past 20 years, changes in land cover and vegetation were investigated based on multi-temporal remote sensing Landsat TM images. We developed a hierarchical classifier system that uses different feature inputs for specific classes and conducted a classification post-processing approach to improve its accuracy. From our statistical analysis of changes in urban land cover from 1987 to 2007, we conclude that built-up land areas have obviously increased, while farmland has seen in a continuous loss due to urban growth and human activities. A NDVI difference approach was used to extract information on changes in vegetation. A false change information elimination approach was developed based on prior knowledge and statistical analysis. The areas of vegetation cover have been in continuous decline over the past 20 years, although some measures have been adopted to protect and maintain urban vegetation. Given the stability of underground coal exploitation since 1990s, urban growth has become the major driving force in vegetation loss, which is different from the vegetation change driven by coal exploitation mainly before 1990. 展开更多
关键词 urban settlement land cover change VEGETATION hierarchical classifier system URBANIZATION NDVI NDVI difference urban remote sensing
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A Geographic Information Systems approach for classifying and mapping forest management category in Baihe Forestry Bureau, Northeast China 被引量:2
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作者 WANG Shun-zhong SHAO Guo-fan +2 位作者 GU Hui-yan WANG Qing-li DAI Li-min 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期211-215,共5页
This paper demonstrates a Geographic Information Systems (GIS) procedure of classifying and mapping forest management category in Baihe Forestry Burea, Jilin Province, China. Within the study area, Baihe Forestry Bu... This paper demonstrates a Geographic Information Systems (GIS) procedure of classifying and mapping forest management category in Baihe Forestry Burea, Jilin Province, China. Within the study area, Baihe Forestry Bureau land was classified into a two-hierarchy system. The top-level class included the non-forest and forest. Over 96% of land area is forest in the study area, which was further divided into key ecological service forest (KES), general ecological service forest (GES), and commodity forest (COM). COM covered 45.0% of the total land area and was the major forest management type in Baihe Forest Bureau. KES and GES accounted for 21.2% and 29.9% of the total land area, respectively. The forest management zones designed with GIS in this study were then compared with the forest management zones established using the hand draw by the local agency. There were obvious differences between the two products. It suggested that the differences had some to do with the data sources, basic unit and mapping procedures. It also suggested that the GIS method was a useful tool in integrating forest inventory data and other data for classifying and mapping forest zones to meet the needs of the classified forest management system. 展开更多
关键词 Classified forest management Key ecological service forest: GIS: Baihe Forestry Bureau
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Spatial Analysis of Flood Vulnerability Levels in Port Harcourt Metropolis Using GIS 被引量:1
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作者 Olatunde Sunday Eludoyin Vincent Ezikomwor Weli 《Journal of Earth Science and Engineering》 2012年第10期617-623,共7页
The study identified spatial variations in flood vulnerability levels in Port Harcourt metropolis with the use of GIS (geographic information systems). This study considered four factors and these included landuse t... The study identified spatial variations in flood vulnerability levels in Port Harcourt metropolis with the use of GIS (geographic information systems). This study considered four factors and these included landuse types, drainage, residential densities and elevation. The elevation data and drainage data were derived from the topographical map of scale 1:35,000, while the land use types were derived from the imagery of Port Harcourt metropolis downloaded from Google Earth, 2010 version. Both the topographical map and imagery were geo-referenced to geographic coordinates and geographic features were digitized in form of shapefiles using both ArcView GIS 3.3 and ArcGIS 9.2 versions. AHP (analytical hierarchical process) was adopted in this study whereby many flood factors were ranked and overlaid for decision making. The contour data was used to generate the DEM (digital elevation model) through the process called kriging in ArcGIS 9.2. Based on the ranking index, factors considered were reclassified to three levels of vulnerability namely highly vulnerable, moderately vulnerable and lowly vulnerable through ranking method and these reclassified factors were then overlaid using an addition operator. The analysis shows that communities like Eagle Island, Ojimbo, Kidney Island were highly vulnerable to flood while communities like Choba, Ogbogoro, Rumualogu were moderately vulnerable. Communities like Rumuigbo, Rumuodomaya etc. were lowly vulnerable to flood. The highly vulnerable places covered 98.18 km2, moderately vulnerable was 220.46 km2 and lowly vulnerable areas covered 330.77 km2. 展开更多
关键词 Flood monitoring GIS ArcGIS 9.2 ArcView 3.3 KRIGING interpolation vulnerability.
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Thin-bed thickness calculation formula and its approximation using peak frequency 被引量:13
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作者 Sun Luping Zheng Xiaodong Li Jingsong Shou Hao 《Applied Geophysics》 SCIE CSCD 2009年第3期234-240,299,共8页
Quantitative thickness estimation below tuning thickness is a great challenge in seismic exploration. Most studies focus on the thin-beds whose top and bottom reflection coefficients are of equal magnitude and opposit... Quantitative thickness estimation below tuning thickness is a great challenge in seismic exploration. Most studies focus on the thin-beds whose top and bottom reflection coefficients are of equal magnitude and opposite polarity. There is no systematic research on the other thin-bed types. In this article, all of the thin-beds are classified into four types: thin-beds with equal magnitude and opposite polarity, thin-beds with unequal magnitude and opposite polarity, thin-beds with equal magnitude and identical polarity, and thin-beds with unequal magnitude and identical polarity. By analytical study, an equation describing the general relationship between seismic peak frequency and thin-bed thickness was derived which shows there is a Complex implicit non-linear relationship between them and which is difficult to use in practice. In order to solve this problem, we simplify the relationship by Taylor expansion and discuss the precision of the approximation formulae with different orders for the four types of thin-beds. Compared with the traditional amplitude method for thin-bed thickness calculation, the method we present has a higher precision and isn't influenced by the absolute value of top or bottom reflection coefficient, so it is convenient for use in practice. 展开更多
关键词 thin-bed quantitative thickness calculation peak frequency Taylor expansion approximation
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Sensitivity analysis of the De Nitrification and De Composition model for simulating regional carbon budget at the wetlandgrassland area on the Zoige Plateau,China 被引量:3
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作者 WANG Ji-yan LI Ai-nong JIN Hua-an 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1200-1216,共17页
Although mathematical models(e.g., De Nitrification and De Composition(DNDC) provide a powerful tool to study regional carbon budget, it is still difficult to obtain accurate simulation results because there exists la... Although mathematical models(e.g., De Nitrification and De Composition(DNDC) provide a powerful tool to study regional carbon budget, it is still difficult to obtain accurate simulation results because there exists large uncertainties in modeling regional carbon budget. Through the investigation on the sensitivity of model output parameters to the input parameters, sensitivity analysis(SA) has been proved to be able to identify the key sources of uncertainties and be helpful to reduce the model uncertainties. However, some input parameters with discrete values(e.g., land use type and soil type) and the regional effect of the sensitive parameters were rarely examined in SA. In this paper, taking the Zoige Plateau as a case area, we combined the one-factor-ata-time(OAT) with Extended Fourier Amplitude Sensitivity Test(EFAST) to conduct a SA of DNDC for simulating the regional carbon budget, including Gross Primary Productivity(GPP), Net Primary Productivity(NPP), Net Ecosystem Productivity(NEP), autotrophic respiration(Ra), soil microbial heterotrophic respiration(Rh) and ecosystem respiration(Re). The result showed that the combination of OAT and EFAST could test the contribution of the input parameters with discrete values to the output parameters. In DNDC model, land use type and soil type had a significant impact on the regional carbon budget of the Zoige Plateau, and daily temperature was also confirmed to be one of the most important parameters for carbon budget. For the other input parameters, with the change of land use type or soil type at regional scale, the sensitive parameters of carbon budget would vary accordingly. The SA results would provide scientific evidence to optimize DNDC model and they suggested that we should pay attention to the spatial/temporal effect of SA and try to use the appropriate data in simulation of the regional carbon budget. 展开更多
关键词 Sensitivity analysis OAT EFAST DNDC model Carbon budget Zoige Plateau
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Landslide hazards mapping using uncertain Na?ve Bayesian classification method 被引量:3
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作者 毛伊敏 张茂省 +1 位作者 王根龙 孙萍萍 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3512-3520,共9页
Landslide hazard mapping is a fundamental tool for disaster management activities in Loess terrains. Aiming at major issues with these landslide hazard assessment methods based on Naive Bayesian classification techniq... Landslide hazard mapping is a fundamental tool for disaster management activities in Loess terrains. Aiming at major issues with these landslide hazard assessment methods based on Naive Bayesian classification technique, which is difficult in quantifying those uncertain triggering factors, the main purpose of this work is to evaluate the predictive power of landslide spatial models based on uncertain Naive Bayesian classification method in Baota district of Yan'an city in Shaanxi province, China. Firstly, thematic maps representing various factors that are related to landslide activity were generated. Secondly, by using field data and GIS techniques, a landslide hazard map was performed. To improve the accuracy of the resulting landslide hazard map, the strategies were designed, which quantified the uncertain triggering factor to design landslide spatial models based on uncertain Naive Bayesian classification method named NBU algorithm. The accuracies of the area under relative operating characteristics curves(AUC) in NBU and Naive Bayesian algorithm are 87.29% and 82.47% respectively. Thus, NBU algorithm can be used efficiently for landslide hazard analysis and might be widely used for the prediction of various spatial events based on uncertain classification technique. 展开更多
关键词 uncertain Bayesian model LANDSLIDE hazard assessment
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Estimation of Antropogenenic Pressure on Landscapes of Oasises (on Example of Mid and Lower Part of Zarafshan River)
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作者 A. Rakhmatullaev 《Journal of Environmental Science and Engineering》 2011年第9期1126-1130,共5页
The paper discusses about anthropogenic pressure classification system on landscape oasises. As a result, based on designed criteria rates a thematic map titled "Anthropogenic pressure and its consequences on landsca... The paper discusses about anthropogenic pressure classification system on landscape oasises. As a result, based on designed criteria rates a thematic map titled "Anthropogenic pressure and its consequences on landscapes oasises of mid and lower part of Zarafshan River Basin" was developed. The thematic map depicts realthionship between ecological conditions and population diseases along various landscape oasises of the Zarafshan river valley. 展开更多
关键词 Anthropogenic pressure landscapes OASIS criteria PESTICIDES ECOLOGY river basin
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Monitoring Land Use Dynamics in Chanthaburi Province of Thailand Using Digital Remotely Sensed Images 被引量:12
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作者 SHENRUNPING I.KHEORUENROMNE 《Pedosphere》 SCIE CAS CSCD 2003年第2期157-164,共8页
A comprehensive method of image classification was developed for monitoring land use dynamics in Chanthaburi Province of Tailand. RS (Remote Sensing), GIS (Geographical Information System), GPS (Global Positioning Sys... A comprehensive method of image classification was developed for monitoring land use dynamics in Chanthaburi Province of Tailand. RS (Remote Sensing), GIS (Geographical Information System), GPS (Global Positioning System) and ancillary data were combined by the method which adopts the main idea of classifying images by steps from decision tree method and the hybridized supervised and unsupervised classification. An integration of automatic image interpretation, ancillary materials and expert knowledge was realized. Two subscenes of Landsat 5 Thematic Mapper (TM) images of bands 3, 4 and 5 obtained on December 15, 1992, and January 17, 1999, were used for image processing and spatial data analysis in the study. The overall accuracy of the results of classification reached 90%, which was verified by field check.Results showed that shrimp farm land, urban and traffic land, barren land, bush and agricultural developing area increased in area, mangrove, paddy field, swamp and marsh land, orchard and plantation, and tropical grass land decreased, and the forest land kept almost stable. Ecological analysis on the land use changes showed that more attentions should be paid on the effect of land development on ecological environment in the future land planning and management. 展开更多
关键词 image classification land use dynamics remote sensing tropical area
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Rocky Desertification Risk Zone Delineation in Karst Plateau Area:A Case Study in Puding County,Guizhou Province 被引量:15
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作者 ZHANG Panpan HU Yuanman +3 位作者 XIAO Duning LI Xiuzhen YIN Jie HE Hong S 《Chinese Geographical Science》 SCIE CSCD 2010年第1期84-90,共7页
Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management a... Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management and prevention. We chose the middle and lower reaches of the Houzhai underground basin on the karst plateau in Puding County, Guizhou Province, China as the study area and selected land use type, elevation, slope, aspect, lithology and settlement buffer as the main driving factors of the rocky desertification. The potential risk of rocky desertification was quantifed with the factor-weights union method and statistical analysis method. Five grades of rocky desertification risk were delineated based on Geographic Information System. The extremely low, low, moderate, high and extremely high rocky desertification risk zones accounted for 5.01%, 44.17%, 33.92%, 15.59% and 1.30%, respectively. As a whole, the rocky desertification risk level was moderate because the area of low and moderate rocky desertification risk zones occupied 78.09% of the study area. However, more than half of the area (about 50.81%) was predicted to have moderate rocky desertification risk and above, indicating that the study area was subject to rocky desertification. Rocky desertification risk was higher in the southeast and lower in the northwest of the study area. Distinct differences in the distribution of rocky desertification risk zones corresponding to different factors have been found. 展开更多
关键词 rocky desertification rocky desertification risk zone karst plateau Guizhou Province
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Probabilistic Classification of Tree and Shrub Vegetation on Phytogeographic System
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作者 Thomaz Correa e Castro da Costa Andreia Fonseca Silva +1 位作者 Luciana Mara Temponi de Oliveira Joao Herbert Moreira Viana 《Journal of Environmental Science and Engineering(B)》 2015年第6期315-330,共16页
The phytogeographical system for vegetation classification splits the vegetation in first level types: forest and grasslands. The forest type can be recognized in tropical rain forest and seasonal depending on the en... The phytogeographical system for vegetation classification splits the vegetation in first level types: forest and grasslands. The forest type can be recognized in tropical rain forest and seasonal depending on the environmental conditions. This determines the occurrence of deciduous species in big or small quantity. And the grasslands are Savannah in majority. This work proposed probabilistic methods to classify these vegetation types based on priori occurrence of species. The test was carded out with forest inventory data using ten vegetation fragments in farm of Embrapa and Cascata's park in Sete Lagoas city, Minas Gerais, Brazil. The distribution of species with occurrence in different types was adapted to set theory and Bayes theorem. In this way, it is possible to calculate belonging of species on vegetation types. The results were compared with usual classification. The main contribution of probabilistic methods was to increase the information to classify tree and shrub vegetation inventoried. It is especially recommended for transition regions between vegetation types. 展开更多
关键词 Sets theory BAYES SAVANNAH FOREST transition.
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New One-Way Line for Electric Transmission System 被引量:3
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作者 Michael Bank 《Journal of Energy and Power Engineering》 2012年第8期1320-1327,共8页
There are three well known types of wire lines for transmitting electrical energy or information. The first type is ordinary two wires line (below A-Line). The second type is so-called single-wire line, where ground... There are three well known types of wire lines for transmitting electrical energy or information. The first type is ordinary two wires line (below A-Line). The second type is so-called single-wire line, where ground plays the role instead of second wire. Polyphase systems belong to the third type, three phase system is the most popular among them. The purpose of this article is another attempt to build a one-wired (without ground) system--the transmission of electrical energy. In this paper an original idea of building such a system is justified, the results of simulations and laboratory modeling are presented. It is shown that the proposed method can reduce the cost of electric transmission lines, the losses in them and significantly reduce interferences. 展开更多
关键词 Electrical lines three phase system one line system TRANSFORMER delay line.
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Multiple Uses of Rangelands in Alborz Mountain (Iran)
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作者 Roja Safaeian Hosein Arzani +1 位作者 Hosein Azamivand Nosratolah Safaeian 《Journal of Agricultural Science and Technology(A)》 2012年第2期246-251,共6页
The most precious ecological function of rangelands is the conservation of soil and water as well as supplying forage for domestic and wild animals. Such an ecological bio habitat, or in the other words the profession... The most precious ecological function of rangelands is the conservation of soil and water as well as supplying forage for domestic and wild animals. Such an ecological bio habitat, or in the other words the profession of rangelands, has been subject to disorders for the variety of reasons since many years ago. Floods, hungry animals and desertification are the consequences of such disorders. Therefore, the rangeland managers have suggested the multiple usages of rangelands based on their existing talent and efficiency which is called "rangeland suitability". In this research, based on bio-diversity potentials of the region, the recognition and functions of plants of Alborz Mountain rangelands have been considered as rangeland management tools. The sampling has been carried out in work units (combination of traditional systems in plant types) randomly-systematically by setting ten 50 m transects and putting down a metal bar. In this way, the relative frequency of medicinal and nectarous rangeland plants in work units has been evaluated. Planning for multiple usage of rangelands were performed based on two criteria of suitability of medicinal and nectarous plants, 1991 Food and Agriculture Organization (FAO) method, and using Geographical Information Systems (GIS) with the scale of 1:50,000. The best-growing habitat of the plants was selected based on the modeling. By proving the existence of environmental gradient, one can recommend the above methods to study the environmental factors as complementary to incarnation models theories. 展开更多
关键词 Suitability of rangeland model multiple uses Alborz Mountain FAO.
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