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Mapping and understanding degradation of alpine wetlands in the northern Maloti-Drakensberg, southern Africa
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作者 Johan van TOL 《Journal of Mountain Science》 SCIE CSCD 2024年第9期2956-2966,共11页
The alpine terrestrials of the Maloti-Drakensberg in southern Africa play crucial roles in ecosystem functions and livelihoods,yet they face escalating degradation from various factors including overgrazing and climat... The alpine terrestrials of the Maloti-Drakensberg in southern Africa play crucial roles in ecosystem functions and livelihoods,yet they face escalating degradation from various factors including overgrazing and climate change.This study employs advanced Digital Soil Mapping(DSM)techniques coupled with remote sensing to map and assess wetland coverage and degradation in the northern Maloti-Drakensberg.The model achieved high accuracies of 96%and 92%for training and validation data,respectively,with Kappa statistics of 0.91 and 0.83,marking a pioneering automated attempt at wetland mapping in this region.Terrain attributes such as terrain wetness index(TWI)and valley depth(VD)exhibit significant positive correlations with wetland coverage and erosion gully density,Channel Network Depth and slope were negative correlated.Gully density analysis revealed terrain attributes as dominant factors driving degradation,highlighting the need to consider catchment-specific susceptibility to erosion.This challenge traditional assumptions which mainly attribute wetland degradation to external forces such as livestock overgrazing,ice rate activity and climate change.The sensitivity map produced could serve as a basis for Integrated Catchment Management(ICM)projects,facilitating tailored conservation strategies.Future research should expand on this work to include other highland areas,explore additional covariates,and categorize wetlands based on hydroperiod and sensitivity to degradation.This comprehensive study underscores the potential of DSM and remote sensing in accurately assessing and managing wetland ecosystems,crucial for sustainable resource management in alpine regions. 展开更多
关键词 Digital Soil mapping Gully density Integrated catchment management Remote sensing Wetland degradation
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Monitoring Zenithal Total Delays over the three different climatic zones from IGS GPS final products:A comparison between the use of the VMF1 and GMF mapping functions 被引量:4
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作者 Benachour Labib Jianguo Yan +2 位作者 Jean-Pierre Barriot Fangzhao Zhang Peng Feng 《Geodesy and Geodynamics》 2019年第2期93-99,共7页
The International GNSS Service(IGS) final products(ephemeris and clocks-correction) have made the GNSS an indispensable low-cost tool for scientific research, for example sub-daily atmospheric water vapor monitoring. ... The International GNSS Service(IGS) final products(ephemeris and clocks-correction) have made the GNSS an indispensable low-cost tool for scientific research, for example sub-daily atmospheric water vapor monitoring. In this study, we investigate if there is a systematic difference coming from the choice between the Vienna Mapping Function 1(VMF1) and the Global Mapping Function(GMF) for the modeling of Zenith Total Delay(ZTD) estimates, as well as the Integrated Precipitable Water Vapor(IPWV) estimates that are deduced from them. As ZTD estimates cannot be fully separated from coordinate estimates, we also investigated the coordinate repeatability between subsequent measurements.For this purpose, we monitored twelve GNSS stations on a global scale, for each of the three climatic zones(polar, mid-latitudes and tropical), with four stations on each zone. We used an automated processing based on the Bernese GNSS Software Version 5.2 by applying the Precise Point Positioning(PPP)approach, L3 Ionosphere-free linear combination, 7 cutoff elevation angle and 2 h sampling. We noticed an excellent agreement with the ZTD estimates and coordinate repeatability for all the stations w.r.t to CODE(the Center for Orbit Determination in Europe) and USNO(US Naval Observatory) products, except for the Antarctic station(Davis) which shows systematic biases for the GMF related results. As a final step, we investigated the effect of using two mapping functions(VMF1 and GMF) to estimate the IPWV,w.r.t the IPWV estimates provided by the Integrated Global Radiosonde Archive(IGRA). The GPS-derived IPWV estimates are very close to the radiosonde-derived IPWV estimates, except for one station in the tropics(Tahiti). 展开更多
关键词 International GNSS Service (IGS) VIENNA mapPING FUNCTION 1 (VMF1) Global mapPING FUNCTION (GMF) Precise Point Positioning (PPP) Zenith TOTAL DELAY (ZTD) Zenith Wet DELAY (ZWD) Integrated Precipitable Water Vapor (IPWV)
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Creation of New Global Land Cover Map with Map Integration 被引量:3
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作者 Koki Iwao Kenlo Nishida Nasahara +3 位作者 Tsuguki Kinoshita Yoshiki Yamagata Dave Patton Satoshi Tsuchida 《Journal of Geographic Information System》 2011年第2期160-165,共6页
We present here a new approach to the development of a global land cover map. We combined three existing global land cover maps (MOD12, GLC2000, and UMD) based on the principle that the majority view prevails and vali... We present here a new approach to the development of a global land cover map. We combined three existing global land cover maps (MOD12, GLC2000, and UMD) based on the principle that the majority view prevails and validated the resulting map by using information collected as part of the Degree Confluence Project (DCP). We used field survey information gathered by DCP volunteers from 4211 worldwide locations to validate the new land cover map, as well as the three existing land cover maps that were combined to create it. Agreement between the DCP-derived information and the land cover maps was 61.3% for our new land cover map, 60.3% for MOD12, 58.9% for GLC2000, and 55.2% for UMD. Although some of the improvements we achieved were not statistically significant, this project has shown that an improved land cover map can be developed and well-validated globally using our method. 展开更多
关键词 GLOBAL Land COVER map map integration Validation
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ELXED POINT THEOREM OF COMPOSITION g-CONTRACTION MAPPING AND ITS APPLICATIONS 被引量:1
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作者 YUN Tian-quan(云天铨) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1132-1139,共8页
Any composition sequential mapping, periodic composition mapping of a complete non-empty metric space M into M with geometric mean contraction ratio less than 1 ( simplifying as 'g-contraction mapping' ) has a... Any composition sequential mapping, periodic composition mapping of a complete non-empty metric space M into M with geometric mean contraction ratio less than 1 ( simplifying as 'g-contraction mapping' ) has a unique fixed point in M . Applications of the theorem to the proof of existence and uniqueness of the solutions of a set of non-linear differential equations and a coupled integral equations of symmetric bending of shallow shell of revolution are given. 展开更多
关键词 CONTRACTION mapPING g-contraction mapPING BANACH CONTRACTION mapPING theOREM functional analysis differential EQUATION integral EQUATION SHALLOW shell
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From the second gradient operator and second class of integral theorems to Gaussian or spherical mapping invariants 被引量:1
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作者 殷雅俊 吴继业 +1 位作者 黄克智 范钦珊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第7期855-862,共8页
By combining of the second gradient operator, the second class of integral theorems, the Gaussian-curvature-based integral theorems and the Gaussian (or spherical) mapping, a series of invariants or geometric conser... By combining of the second gradient operator, the second class of integral theorems, the Gaussian-curvature-based integral theorems and the Gaussian (or spherical) mapping, a series of invariants or geometric conservation quantities under Gaussian (or spherical) mapping are revealed. From these mapping invariants important transformations between original curved surface and the spherical surface are derived. The potential applications of these invariants and transformations to geometry are discussed 展开更多
关键词 the second gradient operator integral theorem Gaussian curvature Gaussian (or spherical) mapping mapping invariant
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THE EXISTENCE AND UNIQUENESS OF SOLUTION FOR A CLASS OF STOCHASTIC FUNCTIONAL EQUAFIONS ON S.P.SPACE 被引量:10
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作者 刘坤会 秦明达 陆传赉 《Acta Mathematica Scientia》 SCIE CSCD 2001年第3期391-400,共10页
This paper is concerned with the existence and uniqueness of solution for a class of stochastic functional equation: X =φ(X), where φ: B → B and B is a Banach space consisted of all left-continuous, (■_t)-adapted ... This paper is concerned with the existence and uniqueness of solution for a class of stochastic functional equation: X =φ(X), where φ: B → B and B is a Banach space consisted of all left-continuous, (■_t)-adapted processes. Also, the main result is applied to some S.D.E (or S.I.E.). And the authors adopted some of the results in current research in the models of stochastic control recently. This paper proves the ekistence and uniquence and uniqueness of solution for stochastic functional equation. A series of corollaries are deduced from the special examples of the theorems in this paper. 展开更多
关键词 Stochastic functional equation stochastic differential (integral) equation principle of contraction mapping
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An Integrated Map of Soybean Physical Map and Genetic Map 被引量:3
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作者 QI Zhaoming LI Hui +4 位作者 WU Qiong SUN Yanan LIU Chunyan HU Guohua CHEN Qingshan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第2期12-16,共5页
Soybean is a major crop in the world, and it is a main source of plant proteins and oil. A lot of soybean genetic maps and physical maps have been constructed, but there are no integrated map between soybean physical ... Soybean is a major crop in the world, and it is a main source of plant proteins and oil. A lot of soybean genetic maps and physical maps have been constructed, but there are no integrated map between soybean physical map and genetic map. In this study, soybean genome sequence data, released by JGI (US Department of Energy's Joint Genome Institute), had been downloaded. With the software Blast 2.2.16, a total of 161 super sequences were mapped on the soybean public genetic map to construct an integrated map. The length of these super sequences accounted for 73.08% of all the genome sequence. This integrated map could be used for gene cloning, gene mining, and comparative genome of legume. 展开更多
关键词 soybean genome integrated map physical map genetic map local blast
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A Hierarchy of Lax Integrable Lattice Equations, Liouville Integrability and a NewIntegrable Symplectic Map 被引量:6
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作者 XUXi-Xiang ZHANGYu-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期321-328,共8页
A discrete matrix spectral problem and the associated hierarchy of Lax integrable lattice equations are presented, and it is shown that the resulting Lax integrable lattice equations are all Liouville integrable discr... A discrete matrix spectral problem and the associated hierarchy of Lax integrable lattice equations are presented, and it is shown that the resulting Lax integrable lattice equations are all Liouville integrable discrete Hamiltonian systems. A new integrable symplectic map is given by binary Bargmann constraint of the resulting hierarchy. Finally, an infinite set of conservation laws is given for the resulting hierarchy. 展开更多
关键词 lattice soliton equation discrete Hamiltonian system Liouville integrability NONLINEARIZATION symplctic map conservation law
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A Hierarchy of Integrable Nonlinear Lattice Equations and New Integrable Symplectic Map 被引量:2
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作者 XUXi-Xiang DONGHuan-He 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第5期523-528,共6页
A discrete spectral problem is discussed, and a hierarchy of integrable nonlinear lattice equations related to this spectral problem is devised. The new integrable symplectic map and finite-dimensional integrable syst... A discrete spectral problem is discussed, and a hierarchy of integrable nonlinear lattice equations related to this spectral problem is devised. The new integrable symplectic map and finite-dimensional integrable systems are given by nonlinearization method. The binary Bargmann constraint gives rise to a B?cklund transformation for the resulting integrable lattice equations. 展开更多
关键词 integrable lattice equation Hamiltonian system NONLINEARIZATION symplectic map Backlund transformation
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A Hierarchy of Integrable Lattice Soliton Equations and New Integrable Symplectic Map 被引量:1
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作者 SUN Ye-Peng CHEN Deng-Yuan XU Xi-Xiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期405-410,共6页
Starting from a discrete spectral problem, a hierarchy of integrable lattice soliton equations is derived. It is shown that the hierarchy is completely integrable in the Liouville sense and possesses discrete bi-Hamil... Starting from a discrete spectral problem, a hierarchy of integrable lattice soliton equations is derived. It is shown that the hierarchy is completely integrable in the Liouville sense and possesses discrete bi-Hamiltonian structure. A new integrable symplectic map and finite-dimensional integrable systems are given by nonlinearization method. The binary Bargmann constraint gives rise to a Biicklund transformation for the resulting integrable lattice equations. At last, conservation laws of the hierarchy are presented. 展开更多
关键词 lattice soliton equation discrete Hamiltonian structure integrable symplectic map
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An Integrated Genetic,Physical and Transcript Map of Homoeologous Chromosomes 12 and 26 in Upland Cotton(Gossypium hirsutum L.) 被引量:2
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作者 KOHEL Russell J CHO Jaemin TOMKINS Jeffrey YU John Z 《棉花学报》 CSCD 北大核心 2008年第S1期22-,共1页
While Upland cotton(Gossypium hirsutum L.) represents 95% of the world production,its genetic improvement is hindered by the shortage of effective genomic tools and resources.The
关键词 An Integrated Genetic Physical and Transcript map of Homoeologous Chromosomes 12 and 26 in Upland Cotton Gossypium hirsutum L
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CSMCCVA:Framework of cross-modal semantic mapping based on cognitive computing of visual and auditory sensations 被引量:1
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作者 刘扬 Zheng Fengbin Zuo Xianyu 《High Technology Letters》 EI CAS 2016年第1期90-98,共9页
Cross-modal semantic mapping and cross-media retrieval are key problems of the multimedia search engine.This study analyzes the hierarchy,the functionality,and the structure in the visual and auditory sensations of co... Cross-modal semantic mapping and cross-media retrieval are key problems of the multimedia search engine.This study analyzes the hierarchy,the functionality,and the structure in the visual and auditory sensations of cognitive system,and establishes a brain-like cross-modal semantic mapping framework based on cognitive computing of visual and auditory sensations.The mechanism of visual-auditory multisensory integration,selective attention in thalamo-cortical,emotional control in limbic system and the memory-enhancing in hippocampal were considered in the framework.Then,the algorithms of cross-modal semantic mapping were given.Experimental results show that the framework can be effectively applied to the cross-modal semantic mapping,and also provides an important significance for brain-like computing of non-von Neumann structure. 展开更多
关键词 multimedia neural cognitive computing (MNCC) brain-like computing cross-modal semantic mapping (CSM) selective attention limbic system multisensory integration memory-enhancing mechanism
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Discourse Analysis of packages in Chinese Cross Talk from Conceptual Integration Theory
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作者 翟莉 《海外英语》 2017年第3期233-234,共2页
Packages in Chinese cross talk are the origin of cross talk humor.By using the literature investigation method,the paper find the effect of humor when create the packages and unpack the packages,which is the process t... Packages in Chinese cross talk are the origin of cross talk humor.By using the literature investigation method,the paper find the effect of humor when create the packages and unpack the packages,which is the process that audiences construct mental spaces and create mappings between mental spaces,but the detail process of mental spaces and the mappings of mental spaces is uncertain.Thus,the paper uses literature investigation and illustration as the main research methods.This paper means to make a better understanding of the humor of cross talk and can help to create more humor discourse. 展开更多
关键词 cross talk PACKAGES conceptual integration theory mental spaces mapPING
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ON THE PROBLEM OF DISSIPATIVE PERTURBATIONS OF NONEXPANSIVE MAPPINGS
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作者 LUO Yuan-song(罗元松) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第4期478-482,共5页
Some Fixed point theorems for mappings of the type - A + T are established, where P is a cone in a Hilbert space, A: P --> 2(P) is an accretive mappings and T: P --> P is a nonexpansive mappings. In application,... Some Fixed point theorems for mappings of the type - A + T are established, where P is a cone in a Hilbert space, A: P --> 2(P) is an accretive mappings and T: P --> P is a nonexpansive mappings. In application, the results presented in the paper are used to study the existence problem of solutions far a class of nonlinear integral equations in L-2 (Omega). 展开更多
关键词 nonexpansive mapping accretive mapping fixed point theorem nonlinear integral equation
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A Hierarchy of Integrable Nonlinear Lattice Equations and New Integrable Symplectic Map
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作者 XU Xi-Xiang DONG Huan-He 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第11期523-528,共6页
A discrete spectral problem is discussed, and a hierarchy of integrable nonlinear lattice equations related tothis spectral problem is devised. The new integrable symplectic map and finite-dimensional integrable syste... A discrete spectral problem is discussed, and a hierarchy of integrable nonlinear lattice equations related tothis spectral problem is devised. The new integrable symplectic map and finite-dimensional integrable systems are givenby nonlinearization method. The binary Bargmann constraint gives rise to a Backlund transformation for the resultingintegrable lattice equations. 展开更多
关键词 INTEGRABLE lattice equation HAMILTONIAN system nonlinearization SYMPLECTIC map BACKLUND transformation
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A REMARK ON THE DERIVATE OF SET-VALUED MAPPING 被引量:1
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作者 Chen Bing(Dept. of Math. Jinzhou Teachers CollegeJinzhou 121003) 《数学研究》 CSCD 1994年第1期51-55,共5页
AREMARKONTHEDERIVATEOFSET-VALUEDMAPPING¥ChenBing(Dept.ofMath.JinzhouTeachersCollegeJinzhou121003)Abstract:Th... AREMARKONTHEDERIVATEOFSET-VALUEDMAPPING¥ChenBing(Dept.ofMath.JinzhouTeachersCollegeJinzhou121003)Abstract:Thederivateofset-va... 展开更多
关键词 集值映射 H-导出数 集值积分 巴拿赫空间
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Comparison of Digital Maps: Recognition and Quantitative Measure of Changes
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作者 Lev Spivak Ivan Spivak +1 位作者 Alexey Sokolov Sergey Voinov 《Journal of Geographic Information System》 2014年第5期415-422,共8页
A new methodology of comparing digital raster maps was proposed which allows not only detecting changes in the maps, but also obtaining quantitative measures of the importance of selected differences. Procedure of obj... A new methodology of comparing digital raster maps was proposed which allows not only detecting changes in the maps, but also obtaining quantitative measures of the importance of selected differences. Procedure of object interpretation of satellite images and forming of OMT (Object Map of Territory) is described. A list of allowable differences between two OMTs is defined. Two steps technique of quantitative measuring is proposed. At the first stage functions are constructed for calculating local measures of differences in the amount, areas and locations of objects on the map, as well as relations between the objects. In the second stage local measures are used to calculate the integral measure in order to get generalized assessment of difference between maps. The methods for constructing functions which calculate local and integral measures of differences are described. Examples of comparing and measuring the differences between OMTs are provided. Obtained results by utilizing this technique can be used to analyze trends, forecast of development and might be helpful for choosing most efficient scenarios for sustainable spatial planning and land management. 展开更多
关键词 mapS COMPARISON Object map of TERRITORY Change Detection Local MEASURE of DIFFERENCE INTEGRAL MEASURE of DIFFERENCE Sustainable Spatial Planning and Land Management
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Mapping Correlation Dimension along the Wall Region of a High-Flux Gas-Solid Riser Using Embedded Solid Concentration Time Series
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作者 Justin M. Jeremiah Samwel V. Manyele +1 位作者 Abraham K. Temu Jesse-X. Zhu 《Engineering(科研)》 2018年第10期655-679,共25页
Analysis of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using embedded solid concentration time series collected from a 76 mm internal diameter and 10 m high riser of a circulating flui... Analysis of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using embedded solid concentration time series collected from a 76 mm internal diameter and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s air velocity and 50 to 550 kg/m2s solids flux of spent fluid catalytic cracking (FCC) catalyst particles with 67 μm mean diameter and density of 1500 kg/m3. Data were analyzed using prepared FORTRAN 2008 code to get correlation integral followed by determination of correlation dimensions with respect to the hyperspherical radius and their profiles, plots of which were studied. It was found that correlation dimension profiles at the centre have single peak with higher values than the wall region profiles. Towards the wall, these profiles have double or multiple peaks showing bifractal or multifractal flow behaviors. As the velocity increases the wall region profiles become random and irregular. Further it was found that, as the height increases the correlation dimension profiles shift towards higher hyperspherical radius at the centre and towards lower hyperspherical radius in the wall region at r/R = 0.81. The established method of mapping correlation dimension profiles in this study forms a suitable tool for analysis of high-flux riser dynamics compared to other analyses approaches. However, further analysis is recommended to other gas-solid CFB riser of different dimensions operated at high-flux conditions using the established method. 展开更多
关键词 CORRELATION Integral mapPING CORRELATION Dimension High-Flux GAS-SOLID RISER EMBEDDED Solid Concentration Time Series
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Soundscape evaluation and integrated humanist ecology of audiovisual sense in Hangzhou Gongshu section of the Beijing-Hangzhou Grand Canal
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作者 SHI Jian-ren JIN Shu-min YANG Yi 《Ecological Economy》 2022年第3期225-230,共6页
Located at the end of the Beijing-Hangzhou Canal,Hangzhou has a historical and cultural heritage with an abundance of acoustic and visual landscape.The paper introduces the concept of“soundscape”into the canal lands... Located at the end of the Beijing-Hangzhou Canal,Hangzhou has a historical and cultural heritage with an abundance of acoustic and visual landscape.The paper introduces the concept of“soundscape”into the canal landscape design,and analyzes its characteristics through documentary analysis,questionnaire method,soundscape walk method,grid method and statistical analysis method.Besides,GIS is also used to present the analysis in a visualized way.The study adopt the increase,decrease and protect design methods which are commonly used in soundscape and the landscape combination methods derived from the classic landscape rules.Eventually,the design is performed in a targeted manner from the perspective of the integrated design of vision and soundscape,offering a optimum proposal and construction strategy.It is hoped that it can promote the design of the integrated acoustic-visual environment of the canal so as to improve the overall spatial environment quality of the urban canal. 展开更多
关键词 SOUNDSCAPE integrated design of vision and soundscape soundscape map the Beijing-Hangzhou Canal
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Mapping the genetic architecture of developmental modularity in ornamental plants
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作者 Zhenying Wen Libo Jiang +7 位作者 Mingyu Li Ang Dong Meixia Ye Juan Meng Ping Li Tangren Cheng Qixiang Zhang Lidan Sun 《Ornamental Plant Research》 2021年第1期13-22,共10页
Developmental modularity,i.e.,coherent organization and function of developmentally related traits,is an emergent property of organismic development and evolution.However,knowledge about how modular variation and evol... Developmental modularity,i.e.,coherent organization and function of developmentally related traits,is an emergent property of organismic development and evolution.However,knowledge about how modular variation and evolution are driven genetically is still limited.Here,using ornamental plants as an example,we propose a computational framework to map,visualize and annotate the genetic architecture of trait modularity by integrating modularity theory into system mapping,a statistical model for multifaceted genetic mapping of complex traits.A developmental module can be viewed as an ecosystem,in which the constituting components compete for space and resources or cooperate symbiotically to organize its function and behavior.This interactive process is quantified by mathematical models and evolutionarily interpreted by game theory.The proposed framework can test whether and how genes regulate the coordination of different but interconnected traits through their competition or cooperation to downstream developmental modularity. 展开更多
关键词 integrating ORNAMENTAL mapPING
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