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Analysis on Landscape Pattern of Urban Green Space in Tianjin City 被引量:1
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作者 孙艳玲 郭鹏 马振兴 《Journal of Landscape Research》 2011年第1期25-27,30,共4页
Based on IKONOS satellite image in August of 2008,and by using GIS technique and spatial pattern analysis software FRAGSTATS,the paper analyzed landscape pattern of urban green space in Tianjin City from the aspects o... Based on IKONOS satellite image in August of 2008,and by using GIS technique and spatial pattern analysis software FRAGSTATS,the paper analyzed landscape pattern of urban green space in Tianjin City from the aspects of patch composition and level of category and landscape.The result showed that there were manymin-sized patches in Tianjin City while large patches occupied a large proportion of the total area of green space.Green spaces were unbalanced in distribution and unreasonable in structure.It suggested adjusting the structure of urban green space,reducing the degree of landscape fragmentation,strengthening the construction of large and mid-sized green patches,so as to improve ecological function of green space. 展开更多
关键词 URBAN green space LANDSCAPE pattern TIANJIN CITY
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Space Pattern of Rural Leisure Tourism Development in Southwest Minority Area——A Case Study of Ethnic Minority Area in Southeast Chongqing
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作者 陶少华 《Journal of Landscape Research》 2010年第8期81-83,共3页
On the basis of analysis of current research documents on rural leisure tourism, taking ethnic minority area of Southeast Chongqing for example, the paper expounded ecology, culture, authenticity and uniqueness of rur... On the basis of analysis of current research documents on rural leisure tourism, taking ethnic minority area of Southeast Chongqing for example, the paper expounded ecology, culture, authenticity and uniqueness of rural leisure tourist resources in ethnic minority area, and city-dependent, scenic area-dependent, traffic route-dependent and remote characteristic village type of space pattern. 展开更多
关键词 Rural LEISURE tourism ETHNIC MINORITY area of SOUTHEAST Chongqing Resources feature space pattern
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Pattern Change of Urban Green Space in Beijing from 2000 to 2010 被引量:1
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作者 ZHANG Biao LI Qingxu +1 位作者 XIE Gaodi SHI Yunting 《Journal of Landscape Research》 2017年第4期67-73,80,共8页
With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators... With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators and planners to optimize the urban development areas and define the ecological protection red lines. Based on the SPOT images and field investigation data of urban green spaces within the sixth ring road of Beijing in 2000, 2005 and 2010, the study investigated the dynamic changes of urban green spaces in this area, by means of GIS techniques and landscape ecology methods. The results indicated that green spaces in Beijing have decreased by 207 km2 from 2000 to 2010 at the expense of agricultural lands and waters. Although there has been some increases in urban forests and grasslands, it cannot compensate the rapid decrease of urban green spaces. The land cover types conversion occurred mainly in the areas between the fifth and sixth ring roads while the zones encircled by the fourth ring road had a little change. In addition, landscape metrics such as number of patches(NP) and shape index(SHAPE) increased, but the mean nearest-neighbor distance(MNN), aggregation index(AI) and patch cohesion index(COHESION) decreased during the period of 2000-2010. Also green landscapes became considerably isolated and fragmented. The study disclosed the obvious changes of green space size, composition and layout in urban districts of Beijing City from 2000 to 2010, and highlighted that construction of urban green space should consider not only the geometric or aesthetic effect, but also the increase of vertical green volume and optimization of spatial layout to fully develop the ecological service functions of green spaces. 展开更多
关键词 Urban green space Landscape pattern metrics Land cover BEIJING
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Investigating the Effect of Sidewalk Flooring on the Behavioral Pattern (Walking) of Citizens in Urban Spaces (Case Study: Vali asr St., Tehran)
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作者 Hazhir Rasoulpour Masoud Mamandi 《Journal of Construction Research》 2019年第2期30-37,共8页
The present study has evaluated the effect of architectural forms on the walking activity of citizens as a behavioral model in urban physical spaces.The research hypothesis claims that by designing purposeful and appr... The present study has evaluated the effect of architectural forms on the walking activity of citizens as a behavioral model in urban physical spaces.The research hypothesis claims that by designing purposeful and appropriate architectural forms,the behavior and actions of users in urban physical spaces can be to some extent,it designed or controlled,and that the pattern and domains of human behavior in urban streets are the result of the components of environmental quality that are included in the design of that street.The present theoretical proposition has been tested in two sequences from Valiasr Street in Tehran.At the theoretical level,the research method is descriptive-analytical and at the experimental level,it is a survey that has been done using the behavioral research method.The results show that the floor form and street form are the most influential architectural forms in urban physical spaces on the activity of users walking from space in the study sample.Also,some environmental factors have a direct effect on human reactions;The research findings show that people’s speed is directly related to the dimensions of sidewalk carpets and a person tries to take a step according to the senses he receives from the sidewalk flooring form and as a result his speed changes according to those forms. 展开更多
关键词 Architectural forms Behavioral patterns Physical spaces City
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Space-time Dynamics of Dendroctonus valens Population in China and Spatial Sampling Technique based on Its Spatial Distribution Pattern
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作者 Pan Jie Wang Tao +2 位作者 Zong Shixiang Wen Junbao Luo Youqing 《Plant Diseases and Pests》 CAS 2015年第3期20-24,38,共6页
Red turpentine beetle (RTB), Dendroctongs valens LeConte, is a destructive forest invasive species in China, it mainly attacks Pings tabuliformis and P. bungeana. So far it has spread rapidly to the provinces of Sha... Red turpentine beetle (RTB), Dendroctongs valens LeConte, is a destructive forest invasive species in China, it mainly attacks Pings tabuliformis and P. bungeana. So far it has spread rapidly to the provinces of Shanxi, Hebei, Henan, Shanxi and Beijing since its first outbreak in Shanxi Province in 1998, and has caused extensive tree mortality. Space-time dynamics of D. valens population and spatial sampling technique based on its spatial distribution pattern were ana- lyzed using geostatistical methods in the pure P. tabuliforis forests and mixedwood stands which were at different damage levels. According to the spatial distribu- tion of D. valeas population, the specific spatial sampling technique was also studied, and then was compared with traditional sampling technique. The spatial sam- piing technique combined with sampling theory and the biological characteristics of D. valens population, which not only could calcnlate the error of the sampling, but also could discuss the optimal sampling number and the optimum size of plot according to different damage levels and different stand types. This helps to explain population expansion and colonization mechanism of D. valens, and to provide a good reference for adopting snitable control measures. 展开更多
关键词 Dendroctonus valens Spatial distribution pattern GEOSTATISTICS space-time dynamics Spatial sampling
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Beam Pattern Scanning (BPS) versus Space-Time Block Coding (STBC) and Space-Time Trellis Coding (STTC)
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作者 Peh Keong TEH Seyed ZEKAVAT 《International Journal of Communications, Network and System Sciences》 2009年第6期469-479,共11页
In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (a... In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (also called beam pattern oscillation), controlled time varying weight vectors are applied to the antenna array elements mounted at the base station (BS). This creates a small movement in the antenna array pattern directed toward the desired user. In rich scattering environments, this small beam pattern movement creates an artificial fast fading channel. The receiver is designed to exploit time diversity benefits of the fast fading channel. Via the application of simple combining techniques, BPS improves the probability-of-error performance and network capacity with minimal cost and complexity. In this work, to highlight the potential of the BPS, we compare BPS and Space-Time Coding (i.e., STBC and STTC) schemes. The comparisons are in terms of their complexity, system physical dimension, network capacity, probability-of-error performance, and spectrum efficiency. It is shown that BPS leads to higher network capacity and performance with a smaller antenna dimension and complexity with minimal loss in spectrum efficiency. This identifies BPS as a promising scheme for future wireless communications with smart antennas. 展开更多
关键词 Antenna Array Beam pattern SWEEPING Transmit Diversity space-TIME Block CODES and space-TIME TRELLIS Coding
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基于Cite Space分析建筑模式语言发展趋势
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作者 何品蓉 焦健 《智能城市》 2024年第2期75-77,共3页
亚历山大模式语言实用性强且应用广泛,研究国内外发展趋势有助于探索国内建筑设计领域差异化发展,促进本土建筑更新。文章利用Cite Space对国外文献进行热点和趋势分析,发现其更注重城市广场、街道和社区的模式研究,具有向宏观尺度发展... 亚历山大模式语言实用性强且应用广泛,研究国内外发展趋势有助于探索国内建筑设计领域差异化发展,促进本土建筑更新。文章利用Cite Space对国外文献进行热点和趋势分析,发现其更注重城市广场、街道和社区的模式研究,具有向宏观尺度发展的趋势;将国内研究脉络划分为初步探索、急速提升和蓬勃发展3个阶段;梳理传统村落、公共空间和图式语言热点领域的研究进展;对比国内外热点和趋势差异,对国内理论应用进行展望。 展开更多
关键词 模式语言 建筑设计 传统民居 公共空间 图式语言
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Analysis of the Green Space System Planning in Small Towns with Yifeng Township, Yancheng City as an Example
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作者 孙新旺 《Journal of Landscape Research》 2009年第12期10-14,共5页
Taking the green space systems in Yifeng Township for an example, this paper analyzed the characteristics and planning principles of green space system in small towns under the background of rapid urbanization. It als... Taking the green space systems in Yifeng Township for an example, this paper analyzed the characteristics and planning principles of green space system in small towns under the background of rapid urbanization. It also proposed the construction of stable ecological green space pattern of towns, the development of forest-type green space and the planning ideas of green space system in small towns that can embody regional context and implement multifunctional composite. 展开更多
关键词 Small TOWNS Green space system planning LANDSCAPE pattern Forest-type
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1984–2023年苏州高新区景观格局演变及景观生态风险评估
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作者 徐曦 钱静 印玉琴 《园林》 2025年第1期93-100,共8页
以苏州高新区为研究对象,通过解译Landsat系列遥感影像建立研究区土地利用数据,分析1984–2023年研究区景观格局演变过程,并构建50 m×50 m的风险小区,利用景观格局指数法对其景观生态风险进行评估。结果表明:近40年间苏州高新区景... 以苏州高新区为研究对象,通过解译Landsat系列遥感影像建立研究区土地利用数据,分析1984–2023年研究区景观格局演变过程,并构建50 m×50 m的风险小区,利用景观格局指数法对其景观生态风险进行评估。结果表明:近40年间苏州高新区景观格局发生了显著变化,主要表现为耕地向建设用地的转变和建设用地自东南向西北、从伴山到临湖的阶梯扩张,而水网格局和水域面积保持稳定,禁开禁采之后城市山林面积也在稳定恢复提高。在这一过程中,研究区平均景观生态风险值呈现出“提升—下降—回升”的趋势,不同时期景观格局的异质性使得景观生态风险分布差异明显,较大影响区域高值区景观生态风险的因素在这一过程中也发生转变,自发城镇化发展阶段高值区主导因素为景观脆弱度,快速城镇化发展阶段主导因素为景观破碎化,区域优化及高质量发展阶段主导因素为景观优势度。了解苏州高新区生态变化过程,识别提取长期处于高值风险的生态薄弱区,并基于研究结果提出区域发展建议,以期推动苏州高新区可持续发展,并为理解快速城市化进程中生态环境变化提供实证依据。 展开更多
关键词 苏州高新区 土地利用 景观格局演变 生态风险评估 时空变化
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Narrative Patterns Research in O·Henry's Novels 被引量:1
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作者 王丽君 邓薇薇 《海外英语》 2011年第8X期350-352,共3页
O·Henry is living in the time when novelists are in the great pursuit of narrative pattern research. Hence his works is inevitably influenced. Beside his humorous language, surprising ends and expressions, O·... O·Henry is living in the time when novelists are in the great pursuit of narrative pattern research. Hence his works is inevitably influenced. Beside his humorous language, surprising ends and expressions, O·Henry's novels in my opinion is also marvelous for his outstanding narrative patterns arrangement. In this article, a research will be conducted onto his narrative pattern in the aspects of narrative perspectives, narrative space and narrative time. By this research, more information and references is intended to obtain for the further study on this area. 展开更多
关键词 NARRATIVE pattern NARRATIVE PERSPECTIVE NARRATIVE space NARRATIVE Time
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DISTRIBUTION PATTERNS OF LEAF AREA INDEX FOR MAJOR CONIFEROUS FOREST TYPES IN CHINA 被引量:4
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作者 Luo Tianxiang Li Wenhua Zhao Shidong Commission for Integrated Survey of Natural Resources, CAS, Beijing 100101 The People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第4期61-73,共13页
Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfull... Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfully estimated from satellite resolution sensors. In this paper, according to the statistical analysis based on a lot of forest plots, the mathematical models of LAI distribution patterns in the hydro thermal spaces for five coniferous forest types in China were established. For the cold temperate larch forests growing in the dry and cold climate, their LAI increases with the increasing of warm index and precipitation in the way of hyperbolic quadratic surface. For the cold temperate spruce fir forests and temperate Pinus tabulaeformis forests, their LAI is negatively related to the annual mean air temperature in the way of the natural exponential curve, in order to adapt to the water oppressed environments. For the subtropical Pinus massoniana forests and Cunninghamia lanceolata forests growing in the warm and moist climate, their LAI is related to the annual mean air temperature in the way of the parabolic quadratic curve. 展开更多
关键词 leaf area index hydro thermal space distribution pattern.
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Urban Green Space Planning Based on Computational Fluid Dynamics Model and Landscape Ecology Principle:A Case Study of Liaoyang City,Northeast China 被引量:9
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作者 ZHOU Yuan SHI Tiemao +4 位作者 HU Yuanman GAO Chang LIU Miao FU Shilei WANG Shizhe 《Chinese Geographical Science》 SCIE CSCD 2011年第4期465-475,共11页
As a result of environmental degradation,urban green space has become a key issue for urban sustainable development.This paper takes Liaoyang City in Northeast China as an example to develop green space planning using... As a result of environmental degradation,urban green space has become a key issue for urban sustainable development.This paper takes Liaoyang City in Northeast China as an example to develop green space planning using the computational fluid dynamics (CFD) model,landscape ecological principles and Geographical Information System (GIS).Based on the influencing factors of topography,building density and orientation,Shou Mountain,Longding Mountain and the Taizi River were selected as the urban ventilation paths to promote wind and oxygen circulation.Oxygen concentration around the green spaces gradually decreased with wind speed increase and wind direction change.There were obvious negative correlation relationships between the oxygen dispersion concentration and urban layout factors such as the building plot ratio and building density.Comparison with the field measurements found that there was significant correlation relationship between simulated oxygen concentration and field measurements (R 2=0.6415,p<0.001),moreover,simulation precision was higher than 92%,which indicated CFD model was effective for urban oxygen concentration simulation.Only less than 10% areas in Liaoyang City proper needed more green space urgently to improve oxygen concentration,mainly concentrated in Baitai and west Wensheng districts.Based on land-scape ecology principle,green space planning at different spatial scales were proposed to create a green space network system for Liaoyang City,including features such as green wedges,green belts and parks.Totally,about 2012 ha of green space need to be constructed as oxygen sources and ventilation paths.Compared with the current green space pattern,proposed green space planning could improve oxygen concentration obviously.The CFD model and research results in this paper could provide an effective way and theory support for sustainable development of urban green space. 展开更多
关键词 green space computational fluid dynamics oxygen dispersion pattern landscape ecology Liaoyang City proper
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SPATIAL GRADIENT ANALYSIS OF URBAN GREEN SPACES COMBINED WITH LANDSCAPE METRICS IN JINAN CITY OF CHINA 被引量:6
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作者 KONG Fan-hua Nobukazu NAKAGOSHI +1 位作者 YIN Hai-wei Akira KIKUCHI 《Chinese Geographical Science》 SCIE CSCD 2005年第3期254-261,共8页
Urban green spaces have been arisen growing concern responded to the social and environmental costs of urban sprawl. A wide range of planning and policies has been and/or will be designed to protect urban green spaces... Urban green spaces have been arisen growing concern responded to the social and environmental costs of urban sprawl. A wide range of planning and policies has been and/or will be designed to protect urban green spaces and optimize their spatial pattern. A better design or planning of urban green space can make a major contribution to quality of environment and urban life, and furthermore can decide whether we can have a sustainable development in the urban area. Information about the status quo of urban green spaces can help planners design more effectively. However, how to quantify and capture such information will be the essential question we face. In this paper, to quantify the urban green space, a new method comprising gradient analysis, landscape metrics and GIS was developed through a case of Jinan City. The results demonstrate: 1) the gradient analysis is a valid and reliable instrument to quantify the urban green space spatial pattern precisely; 2) using moving window, explicit landscape metrics were spatially realized. Compared with quantifying metrics in the entire landscape, it would be better to link pattern with process and establish an important basis for analyzing the ecological and socioeconomic functions of green spaces. 展开更多
关键词 urban green space spatial pattern gradient analysis landscape metrics GIS Jinan City
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Role of street patterns in zone-based traffic safety analysis 被引量:6
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作者 郭强 裴欣 +1 位作者 姚丹亚 黄仕进 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2416-2422,共7页
Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship ... Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship between street pattern characteristics and traffic safety remains underexplored. Based on a zone-based Hong Kong database, the Space Syntax was used to quantify the topological characteristics of street patterns and investigate the role of street patterns and zone-related factors in zone-based traffic safety analysis. A joint probability model was adopted to analyze crash frequency and severity in an integrated modeling framework and the maximum likelihood estimation method was used to estimate the parameters. In addition to the characteristics of street patterns, speed, road geometry, land-use patterns, and temporal factors were considered. The vehicle hours was also included as an exposure proxy in the model to make crash frequency predictions. The results indicate that the joint probability model can reveal the relationship between zone-based traffic safety and various other factors, and that street pattern characteristics play an important role in crash frequency prediction. 展开更多
关键词 street pattern space Syntax joint probability model crash frequency crash severity
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Research of Underwater Bottom Object and Reverberation in Feature Space 被引量:7
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作者 Xiukun Li Zhi Xia 《Journal of Marine Science and Application》 2013年第2期235-239,共5页
The critical technical problem of underwater bottom object detection is founding a stable feature space for echo signals classification. The past literatures more focus on the characteristics of object echoes in featu... The critical technical problem of underwater bottom object detection is founding a stable feature space for echo signals classification. The past literatures more focus on the characteristics of object echoes in feature space and reverberation is only treated as interference. In this paper, reverberation is considered as a kind of signal with steady characteristic, and the clustering of reverberation in frequency discrete wavelet transform (FDWT) feature space is studied. In order to extract the identifying information of echo signals, feature compression and cluster analysis are adopted in this paper, and the criterion of separability between object echoes and reverberation is given. The experimental data processing results show that reverberation has steady pattern in FDWT feature space which differs from that of object echoes. It is proven that there is separability between reverberation and object echoes. 展开更多
关键词 underwater bottom object pattern of reverberation feature clustering feature space underwater object detection
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Characterizing Fracture Spatial Patterns by Using Semivariograms 被引量:1
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作者 许建东 LIN Chiente R.D.JACOBI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第1期89-99,共11页
Semivariogram is applied to fracture data obtained from detailed scanlinesurveys of nine field sites in western New York, USA in order to investigate the spatial patterns ofnatural fractures. The length of the scanlin... Semivariogram is applied to fracture data obtained from detailed scanlinesurveys of nine field sites in western New York, USA in order to investigate the spatial patterns ofnatural fractures. The length of the scanline is up to 36 m. How both fracture spacing and fracturelength vary with distance is determined through semivariogram calculations. In this study, theauthors developed a FORTRAN program to resample the fracture data from the scanline survey. Bycalculating experimental semivariogram, the authors found five different types of spatial patternsthat can be described by linear, spherical, reversed spherical, polynomial I (for aO) models, of which the last three arc newly proposed in this study. Thewell-structured semivariograms of fracture spacing and length indicate that both the location of thefractures and the length distribution within their structure domains are not random. The results ofthis study also suggest that semivariograms can provide useful information in terms of spatialcorrelation distance for fracture location and fracture length. These semivariograms can also beutilized to design more efficient sampling schemes for further surveys. as well as to define thelimits of highly probable extrapolation of a structure domain. 展开更多
关键词 fracture pattern SEMIVARIOGRAM fracture spacing fracture length
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Quantitative division of succession and spatial patterns among different stand developmental stages in Changbai Mountains 被引量:1
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作者 GONG Zhi-wen KANG Xin-gang GU Li 《Journal of Mountain Science》 SCIE CSCD 2019年第9期2063-2078,共16页
Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understand... Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understanding the ecological process of restored vegetation is quite important for ecosystem reconstruction. Distinguishing stand development stages and analyzing the dynamic spatial patterns could provide insights into significant community coexistence mechanisms. In the present study, eight permanent study areas were established according to the substituting space for time method in Changbai Mountains of north-eastern China. The optimal division method was used to quantify the successional series into different stand development stages, and the point pattern analysis method(L(r) function) was used to analyse the dynamic changes in spatial patterns and interspecific associations. Our results suggested that:(1) The stand development process was divided into five stages: the first three stages were poplar-birch secondary forests in different stages of recovery, the fourth stage was thespruce-fir mixed forest, and the last stage was the primary broadleaf-Korean pine forest;(2) The spatial pattern showed an aggregated distribution at a small scale and changed to a random distribution as the scale increased in poplar-birch secondary forests, but the spatial pattern appeared to be randomly distributed in spruce-fir mixed forest and broadleafKorean pine forest;(3) The interspecific associations between pioneer species and climax species changed from negative to positive among the different stand stages, and environmental resources were shared among these species. Interspecific differences in shade tolerance among the tree species were key determinants of forest dynamics and structure. Our study is vital to the understanding of the forest development;thus, the spatial change features should receive greater attention when forest management is being planned and restoration strategies are being developed for the Changbai Mountains. 展开更多
关键词 Dynamic spatial patterns INTERSPECIFIC association Optimal DIVISION method STAND DEVELOPMENTAL STAGES space for time substitution
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COVID-19 lockdown has indirect,non-equivalent effects on activity patterns of Reeves's Pheasant(Syrmaticus reevesii)and sympatric species 被引量:2
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作者 Junqin Hua Shan Tian +5 位作者 Shuai Lu Ziqiang Zhu Xinjie Huang Jisong Tao Jianqiang Li Jiliang Xu 《Avian Research》 SCIE CSCD 2023年第2期231-241,共11页
The outbreak of the COVID-19 pandemic has brought massive shifts in human activities through a global blockade,directly affecting wildlife survival.However,the indirect impacts of changes in human activities are often... The outbreak of the COVID-19 pandemic has brought massive shifts in human activities through a global blockade,directly affecting wildlife survival.However,the indirect impacts of changes in human activities are often easily overlooked.We conducted surveys of Reeves's Pheasant(Syrmaticus reevesii)and its sympatric species by camera traps in forest-type nature reserves in three different scenarios:pre-lockdown,lockdown and postlockdown.An increase in livestock activities observed during the lockdown and post-lockdown period in our study area provided us an opportunity to investigate the indirect impact of the lockdown on wildlife.The prelockdown period was used as a baseline to compare any changes in trends of relative abundance index,activity patterns and temporal spacing of targeted species and livestock.During the lockdown period,the relative abundance index of livestock increased by 50%and there was an increase in daytime activity.Reeves's Pheasant showed avoidance responses to almost all sympatric species and livestock in three different periods,and the livestock avoidance level of Reeves's Pheasant during the lockdown period was significantly and positively correlated with the relative abundance index of livestock.Species-specific changes in activity patterns of study species were observed,with reduced daytime activities of Hog Badger and Raccoon Dog during and after the confinement periods.This study highlights the effect of the COVID-19 lockdown on the responses of wildlife by considering the changes in their temporal and spatial use before,during and after lockdown.The knowledge gained on wildlife during reduced human mobility because of the pandemic aids in understanding the effect of human disturbances and developing future conservation strategies in the shared space,to manage both wildlife and livestock. 展开更多
关键词 Avoidance-attraction ratios Camera trap LIVESTOCK Spatio-temporal activity pattern Temporal spacing
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Analysis of dynamic of two-phase flow in small channel based on phase space reconstruction combined with data reduction sub-frequency band wavelet 被引量:3
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作者 李洪伟 刘君鹏 +2 位作者 李涛 周云龙 孙斌 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第6期1017-1026,共10页
A new method of nonlinear analysis is established by combining phase space reconstruction and data reduction sub-frequency band wavelet. This method is applied to two types of chaotic dynamic systems(Lorenz and Rssler... A new method of nonlinear analysis is established by combining phase space reconstruction and data reduction sub-frequency band wavelet. This method is applied to two types of chaotic dynamic systems(Lorenz and Rssler) to examine the anti-noise ability for complex systems. Results show that the nonlinear dynamic system analysis method resists noise and reveals the internal dynamics of a weak signal from noise pollution. On this basis, the vertical upward gas–liquid two-phase flow in a 2 mm × 0.81 mm small rectangular channel is investigated. The frequency and energy distributions of the main oscillation mode are revealed by analyzing the time–frequency spectra of the pressure signals of different flow patterns. The positive power spectral density of singular-value frequency entropy and the damping ratio are extracted to characterize the evolution of flow patterns and achieve accurate recognition of different vertical upward gas–liquid flow patterns(bubbly flow:100%, slug flow: 92%, churn flow: 96%, annular flow: 100%). The proposed analysis method will enrich the dynamics theory of multi-phase flow in small channel. 展开更多
关键词 Small channel two-phase flow Flow pattern dynamics Phase space reconstruction Data reduction sub-frequency band wavelet
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Analysis on the Application of Image Processing Technology in Clothing Pattern Recognition 被引量:2
20
作者 LIU Jing ZHUANG Meiling +1 位作者 AI Rongyu GAO Ting 《Journal of Donghua University(English Edition)》 EI CAS 2020年第3期224-231,共8页
A clothing pattern is a significant embodiment of regional culture and national characteristics.The recognition of clothing patterns could be realized objectively and accurately by using digital image processing techn... A clothing pattern is a significant embodiment of regional culture and national characteristics.The recognition of clothing patterns could be realized objectively and accurately by using digital image processing technology.The researches on the extraction techniques of various pattern elements were compared and analyzed.Then the researches on clothing pattern color,outline and fabric texture extraction were summarized.And the core technology chain model of clothing pattern extraction was constructed.The research status,the core technology and the development trend of pattern element extraction technology based on two-dimensional images were obtained.What’s more,a reference for the follow-up research of clothing patterns and the technology upgrading of textile and clothing industries were provided. 展开更多
关键词 image filtering color space color clustering edge detection clothing pattern
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