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基于产品特征向量法的壳段成组分类方法研究
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作者 袁维佳 刘海光 +2 位作者 赵军贵 易帆 任秀丽 《机械工程师》 2022年第1期31-33,共3页
采用基于产品特征的向量化方法,将壳段的有关制造特征信息转译为数字,将每种壳段用不同向量表示。通过计算不同向量之间的距离来衡量壳段的相似程度,采用层次聚类法对壳段进行成组分类,为制造单元的构建、工艺布局设计、生产组织模式的... 采用基于产品特征的向量化方法,将壳段的有关制造特征信息转译为数字,将每种壳段用不同向量表示。通过计算不同向量之间的距离来衡量壳段的相似程度,采用层次聚类法对壳段进行成组分类,为制造单元的构建、工艺布局设计、生产组织模式的建立提供输入条件。 展开更多
关键词 产品特征向量 成组分类 层次聚
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工装成组分类及计算机管理
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作者 沈幼珍 《磨床与磨削》 北大核心 1998年第1期12-13,共2页
关键词 工艺装备管理 成组分类 计算机管理
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船舶机械制造中的模糊“分枝-聚类”法
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作者 梁榕辉 《广东造船》 1998年第1期24-26,23,共4页
关键词 模糊 “分枝-聚”法 成组分类
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Seasonal variation in species composition and abundance of tintinnids in Shantou coastal water,China 被引量:2
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作者 刘华雪 黄良民 +2 位作者 谭烨辉 宋星宇 黄建荣 《Marine Science Bulletin》 CAS 2011年第1期80-86,共7页
Two cruises were conducted to study the composition and seasonal variation of tintinnids (Protozoa: Ciliata) in Shantou coast water dudng spring and fall. Remarkable seasonal variations in environmental parameters,... Two cruises were conducted to study the composition and seasonal variation of tintinnids (Protozoa: Ciliata) in Shantou coast water dudng spring and fall. Remarkable seasonal variations in environmental parameters, and tintinnids composition were observed. Tintinnids samples were enumerated and identified from 5 stations. 14 species belonging to 7 genuses of tintinnids were identified, and the dominate species was Leprotintinnus simple in these season. High tintinnids diversity and low abundance occurred in the fall, and on the contrary, low tintinnids diversity and high abundance occurred in the spring. No significant correlation occurred between tintinnids abundance and nutrients. Tintinnids abundance showed negative relationship with salinity (r2=0.63, P 〈 0.05), maybe this was due to the cold raised water carried sum nutrients rise to the surface water in the fall, rich nutrients and high phytoplankton biomass decrease the importance of tintinnids in the energy flow of aquatic food web. 展开更多
关键词 tinUnnids COMPOSITION DISTRIBUTION Shantou coast
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Distribution and composition of tintinnids ciliates in the northern South China Sea during summer 被引量:1
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作者 刘华雪 黄良民 +3 位作者 谭烨辉 宋星宇 黄建荣 李涛 《Marine Science Bulletin》 CAS 2010年第2期38-46,共9页
Tintinnids were enumerated and identified in samples collected from 36 stations between 18°-22°N, 107°-122 °E in the northern South China Sea (NSCS). 44 species belonging to 24 genera of tintinni... Tintinnids were enumerated and identified in samples collected from 36 stations between 18°-22°N, 107°-122 °E in the northern South China Sea (NSCS). 44 species belonging to 24 genera of tintinnids were recorded. The dominant species were He/icostome/la /onga and Tintinnopsis radix. Tintinnids abundance ranged from 0 to 2 200 cell/L, and mean abundance was 221cell/L in the surface water. Tintinnids abundance and species numbers decreased from coast to offshore. Upwelling and Pearl River discharge influenced the distribution of tintinnids by regulating nutrients supply. Maximum abundance (2 200 cell/L) was found in the surface water of A1. Tintinnids abundance showed positive relationship with chlorophyll a (Chl a) concentration, and no significant relationship was found between tintinnids abundance and temperature. 展开更多
关键词 TINTINNIDS COMPOSITION DISTRIBUTION northern South China Sea
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Tillage Pedogenesis of Purple Soils in Southwestern China 被引量:14
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作者 HE Xiubin BAO Yuhai +4 位作者 NAN Hongwei XIONG Donghong WANG Li LIU Yanfeng ZHAO Jingbo 《Journal of Mountain Science》 SCIE CSCD 2009年第2期205-210,共6页
Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO T... Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system (Tlf) is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes. 展开更多
关键词 Tillage impact PEDOGENESIS purple soil MICROMORPHOLOGY southwestern China
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Influences of sea ice on eastern Bering Sea phytoplankton
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作者 周茜茜 王鹏 +3 位作者 陈长平 梁君荣 李炳乾 高亚辉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期458-467,共10页
The influence of sea ice on the species composition and cell density of phytoplankton was investigated in the eastern Bering Sea in spring 2008. Diatoms, particularly pennate diatoms, dominated the phytoplankton commu... The influence of sea ice on the species composition and cell density of phytoplankton was investigated in the eastern Bering Sea in spring 2008. Diatoms, particularly pennate diatoms, dominated the phytoplankton community. The dominant species were Grammonema islandica (Grunow in Van Heurck) Hasle, Fragilariopsis cylindrus (Grunow) Krieger, F. oceanica (Cleve) Hasle, Navicula vanhoeffenii Gran, Thalassiosira antarctica Comber, T. gravida Cleve, T. nordenskioeldii Cleve, and T. rotula Meunier. Phytoplankton cell densities varied from 0.08× 10^4 to 428.8× 10^4 cells/L, with an average of 30.3× 10^4 cells/L. Using cluster analysis, phytoplankton were grouped into three assemblages defined by ice-forming conditions: open wate.r, ice edge, and sea ice assemblages. In spring, when the sea ice melts, the phytoplankton dispersed from the sea ice to the ice edge and even into open waters. Thus, these phytoplankton in the sea ice may serve as a “seed bank” for phytoplankton population succession in the subarctic ecosystem. Moreover, historical studies combined with these results suggest that the sizes of diatom species have become smaller, shifting from microplankton to nannoplankton-dominated communities. 展开更多
关键词 PHYTOPLANKTON sea ice Bering Sea community structure
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Blood is not always thicker than water:The limited effect of kin selection on human kinship in the traditional Chinese family 被引量:1
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作者 Lixing Sun 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第2期182-189,共8页
To examine the importance of kin selection in shaping human societies, this study analyzed the kinship system practiced in traditional China for two millennia and teased apart its underlying genetic and other, presuma... To examine the importance of kin selection in shaping human societies, this study analyzed the kinship system practiced in traditional China for two millennia and teased apart its underlying genetic and other, presumably cultural, components. The results demonstrate that, in the traditional patrilineal Chinese family, both genetic relatedness and the cultural factor of generation were important in determining kinship status for male agnates (genetically related relatives). For female agnates, however, only genetic relatedness was important. Another surprising finding was that the influence of gender was not as important as genetic relatedness. The most interesting finding in this study, however, was that kin selection and culture (i.e., seniority in generation and age) played vastly different roles in different lineages in the Chinese family: for collateral (indirect) agnates, genetic relatedness was the most important factor in determining their kinship status, but for lineal (direct) agnates, its importance was overridden by seniority in generation and age, a cultural factor. Several other bio-cultural factors also explained a considerable amount of variance in kinship status. Since kinship profoundly affected, and was often the foundation of, the legal and social systems in dynastic China, kin selection, while its strength may differ remarkably between lineal and collateral relatives, could act as a selective force in Chinese families 展开更多
关键词 KINSHIP Kin selection Genetic relatedness Chinese family Culture
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Stability of Mbuna Species Populations in Lake Malawi
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作者 Lucious G. Kanyumba Wisdom J. Changadeya +2 位作者 Aggrey J.D. Ambali Leonard A. Kamwanja EmmanuelK.W. Kaunda 《Journal of Environmental Science and Engineering(B)》 2012年第4期543-555,共13页
The first comprehensive study of abundance, richness and distribution of Mbuna in Lake Malawi was carried out in the 1980s. The present study examined changes of species richness and abundance of Mbuna with time. Most... The first comprehensive study of abundance, richness and distribution of Mbuna in Lake Malawi was carried out in the 1980s. The present study examined changes of species richness and abundance of Mbuna with time. Most sites demarcated during the 1980s survey were explored in order to determine changes in abundance and composition of Mbuna over a period of more than 20 years Chi-square analysis revealed significant difference (p 〈 0.05) in abundance of Mbuna between 1983 and 2005 with the exception of Chinyankhwazi and Chinyamwezi where the difference was not significant (p 〉 0.05). Cluster analysis showed changes in species composition between 1983 and 2005 in various sites. Generally, there were more species lost in a given area than new species observed in 2005. Decline in Mbuna species richness might have been caused by siltation, harvesting of Mbuna for food and ornamental fish trade while new species were mostly introduced through translocation from one part of the lake to another. 展开更多
关键词 Mbuna species abundance species richness translocation.
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Earnings disaggregation and analysts' forecasts
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作者 Joshua G Rosette Yong-Chul Shin 《Journal of Modern Accounting and Auditing》 2010年第9期37-49,共13页
Accounting concepts dictate that separately disclosed components should contain separate useful information. This paper examines the relations between income statement components and analysts' earnings forecasts and ... Accounting concepts dictate that separately disclosed components should contain separate useful information. This paper examines the relations between income statement components and analysts' earnings forecasts and forecast errors. Regressions explaining earnings forecasts using earnings components provide a better fit than regression using just aggregate income to explain forecasts. We interpret this as consistent with the hypothesis that analysts use incremental information in components not available in aggregate income. However, additional tests based on predictability of forecast errors indicate that analysts do not incorporate all information available in components into earnings forecasts. In addition, this inefficiency appears to increase at longer forecast horizons. 展开更多
关键词 analysts' earnings forecasts earnings forecast errors earnings components earnings response coefficients
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Hydrocarbon Composition of Different VGO Feedstocks and Its Correlation with FCC Product Distribution
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作者 Song Haitao Jiao Guofeng +3 位作者 Zhu Xinyi Zhou Xiang Zhu Yuxia Da Zhijian 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第1期32-39,共8页
Three different types of VGO were selected and cut into various distillates by true boiling-point distillation (TBD), and the distillates were further separated into different components (saturates, aromatics and r... Three different types of VGO were selected and cut into various distillates by true boiling-point distillation (TBD), and the distillates were further separated into different components (saturates, aromatics and resins) via solid phase extrac- tion (SPE). The hydrocarbon components in saturates and aromatics were characterized on the quasi-molecular level by GC/ MS and CJC/TOF MS. Cracking reactions of VGO, their distillates, and hydrocarbon components (saturates and aromatics) were performed on an ACE (model AP) unit. Nine correlation parameters (mainly based on the previous assumption of basic structure Units, BSU) which could better reflect the structures and compositions of hydrocarbons were put forward based on the quasi-molecular level analysis data, and correlated with FCC product distribution by multi-regression method. A series of correlation formulas were obtained. The formulas were further verified by comparing experimental and calculated FCC yields emanated from two other VGO feedstocks. 展开更多
关键词 fluid catalytic cracking VGO product distribution hydrocarbon composition CORRELATION
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Analysis on Development Trend of the D omestic Interior Design Pattern based on the Regional Characteristics and Cultural Integration
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作者 Congcong Ai Han Xu 《International Journal of Technology Management》 2016年第10期60-62,共3页
Interior is the main space of human activities, which is an important part of human life and design activities, and is the link between spiritual civilization and material civilization. Interior design originates from... Interior is the main space of human activities, which is an important part of human life and design activities, and is the link between spiritual civilization and material civilization. Interior design originates from life, and needs to solve the problem of the material world and spiritual world. People improve the living environment and life quality through interior designs. The style of design depends on the geographical features and various cultures, which refi ects the artistic features and personality. The development history of modern architecture and interior design shows that the style of interior design is an important part of the whole architectural style, which reffects the design features of the whole building. Therefore, interior design and outdoor design should be in harmony. The orientation and characteristics of interior design determine the necessity of the style reforms. The future development trend of interior development may have the following characteristics humanism, green design, nationalization, intelligence and regionalization. 展开更多
关键词 Development Trend DOMESTIC Interior Design Pattern Regional Characteristics Cultural Integration.
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Relationships between high-molecular-weight glutenin subunit (HMW-GS), pentosan and various component contents in different wheat varieties
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作者 LI Chun-xi ZHANG Bei-bei SHAO Yun JIANG Li-na LI Dan-dan 《Journal of Life Sciences》 2007年第1期22-29,33,共9页
The composition of HMW-GS and pentosan and its various component contents in different wheat varieties were analyzed. According to scores of these subunits in several wheat varieties, the correlation relationship betw... The composition of HMW-GS and pentosan and its various component contents in different wheat varieties were analyzed. According to scores of these subunits in several wheat varieties, the correlation relationship between the composition of HMW-GS, subunit combination types and pentosan, various components and component ratio were ascertained. The results showed that HMW-GSs were very diverse which had 11 types. In different varieties, the variation of Ara was obvious while Xyl was not; pentosan and its various component contents were very different, and their coefficient of variability was quite high. The majority of parameters had a significant negative correlation with Glu-1 where Glu-D1 was stronger than other two loci. N, 7, 17+18 and 2+12 subunits had influence on pentosan and its various component contents. But some subunits such as 1 and 5+ 10 which are good for baking quality had little contribution to pentosan and various component contents. The pentosan and various component contents were higher in the varieties which had (N, 7, 2+12) subunit combinations. Additionally, the 21 varieties were classified into 4 categories according to HMW-GS scores and pentosan content. 展开更多
关键词 WHEAT HMW-GS PENTOSAN correlation classification
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Fluorescence Discrimination and Determination Technique for Phytoplankton Composition by Coif2 Wavelet Packet
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作者 DUAN Yali SU Rongguo +3 位作者 SHI Xiaoyong WANG Xiulin ZHU Chenjian SUN Yan 《Journal of Ocean University of China》 SCIE CAS 2013年第1期53-62,共10页
An in vivo fluorescence discrimination technique for phytoplankton population was developed by using Wavelet packet transform, cluster analysis and non-negative least squares. The technique was used to analyze water s... An in vivo fluorescence discrimination technique for phytoplankton population was developed by using Wavelet packet transform, cluster analysis and non-negative least squares. The technique was used to analyze water samples from different sea regions. For simulative mixtures, when dominant species account for 60%, 70%, 80%, 90% at the division level, the correct discrimination ratios (CDRs) are 83.0%, 99.1%, 99.7% and 99.9% with the relative contents of 58.5%, 68.4%, 77.7% and 86.3%, respectively; when the algae dominance are 60%, 70%, 80%, 90%, 100% at the genus level, the CDRs are 86.1%, 94.9%, 95.2%, 96.8% and 96.7%, respectively. For laboratory mixtures, the CDRs are 88.1% and 78.4% at the division and genus level, respectively. For field samples, the CDRs were 91.7% and 80% at the division and genus level, respectively (mesocosm experiments), and the CDRs were 100% and 66.7% at the division and genus level, respectively (Jiaozhou Bay). The fluorometric technique was used to estimate the phytoplankton community composition and relative abundance of different classes for the April 2010 cruise in the Yellow Sea with the results agreeing with those in published papers by other authors. 展开更多
关键词 phytoplankton species wavelet packet transform feature spectra norm spectra database DISCRIMINATION
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A Critical Analysis of the Educational Impact of Steve Fuller's Social Epistemology
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作者 Koichiro Misawa 《Journal of Philosophy Study》 2013年第9期867-879,共13页
In this paper, I examine Steve Fuller's "sociological" social epistemology that must be distinguished from its "philosophical" counterpart. Fuller's sociological social epistemology can prompt deep philosophical... In this paper, I examine Steve Fuller's "sociological" social epistemology that must be distinguished from its "philosophical" counterpart. Fuller's sociological social epistemology can prompt deep philosophical analyses of the conditions for knowledge that themselves bear on what should count as knowledge. That is, it can be a vital prelude to developing an interdisciplinary investigation into educational issues. This paper looks at the three features that form an integral part of Fuller's social epistemology, which is partly elucidatory and partly critical: naturalistic, normative, and organizational aspects. It goes on to explore whether and to what extent Fuller's criticism of an "always already" thesis in philosophy and his idea of "knowledge management" afford an understanding of human knowledge in particular and human development in general. This paper concludes with an observation that Fuller's social epistemology is flawed in some respects but nonetheless is of relevance to the philosophical study of education. 展开更多
关键词 sociological social epistemology Steve Fuller analytic social epistemology the naturalistic aspect ofknowledge the normative aspect of knowledge the organizational aspect of knowledge the "always-already"thesis in philosophy implications for philosophy of education
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Euphemism in Modem American English
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作者 ZHOU Li-na 《Sino-US English Teaching》 2015年第4期265-270,共6页
Euphemism, as the linguistic and cultural phenomenon, is a lubricant in linguistic communication used in different aspects of social lives. With the rapid development of science and progress of human civilization, eup... Euphemism, as the linguistic and cultural phenomenon, is a lubricant in linguistic communication used in different aspects of social lives. With the rapid development of science and progress of human civilization, euphemism, as one of the most important components in English language, has the tendency of multiplying. This paper, based on the development of euphemism in modem American English, sums up the basic features of euphemism in modem American English and analyzes its formation and application in modem American society and culture with the objective of improving learners' communication ability in the context of cross cultural communication. 展开更多
关键词 EUPHEMISM modem American English FORMATION FEATURES APPLICATION
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Studies on Wetland Biodiversity in China
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作者 ZHAO Kuiyi HE Shunping LI Wei 《Bulletin of the Chinese Academy of Sciences》 2010年第4期248-256,共9页
This paper briefly summarizes the history of wetland research, the evolvement of wetland science, and their impacts on the understanding of wetland biodiversity in China. A marsh is the key type and basic component of... This paper briefly summarizes the history of wetland research, the evolvement of wetland science, and their impacts on the understanding of wetland biodiversity in China. A marsh is the key type and basic component of a wetland. Defining the marsh and wetland plants is the basis for understanding the wetland and its biodiversity. The comprehensive multiple factorial classification principles and the multiple developmental models of the wetland are two innovative feats achieved by Chinese scientists, and their application has further promoted ecological research. The CAS Wetland Research Center has made historic contributions to the study of the wetland and its biodiversity in China. Also, the paper discusses several important tasks of wetland and biodiversity research. 展开更多
关键词 BIODIVERSITY WETLAND STUDY China
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Determinants of vigilance in a reintroduced population of Pere David's deer 被引量:4
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作者 Wei ZHENG Guy BEAUCHAMP +2 位作者 Xuelei JIANG Zhongqiu LI Qinglong YANG 《Current Zoology》 SCIE CAS CSCD 2013年第2期265-270,共6页
After being kept in captivity and isolated from natural predators for more than 1,200 years, P6re David's deer has been reintroduced in China and now occurs in a reserve where human activity is the only potential thr... After being kept in captivity and isolated from natural predators for more than 1,200 years, P6re David's deer has been reintroduced in China and now occurs in a reserve where human activity is the only potential threat. Antipredator vigilance i~ an important component of survival for many prey animals in their natural habitat. Do deer still adjust vigilance as a function of risk after such a long period of relaxed predation pressure? Here, we examined vigilance levels in P6re David's deer groups as a function of group size, sex and level of human disturbance. The results showed that individual vigilance significantly decreased with group size in all-female groups but not in all-males or mixed-sex groups. In rutting season, males compete with one another and harass females, and we argue that vigilance is partly aimed at threatening males and that such vigilance increases with group size. This explains why overall vigilance did not vary with group size for males in general and for females in mixed-sex groups. Vigilance increased in more disturbed areas but in in male deer only. The results indicate that despite relaxed predation pressure over centuries, P6re David's deer can still adjust antipredator responses as a function of perceived risk. Such information may become useful in the rewilding programme now under way for this species in China [Current Zoology 59 (2): 265-270, 2013]. 展开更多
关键词 Antipredator vigilance Group size Human disturbance Sexual competition P6re David's deer
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A unified canopy bidirectional reflectance (BRDF) model for row ceops 被引量:3
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作者 YAN BinYan XU XiRu FAN WenJie 《Science China Earth Sciences》 SCIE EI CAS 2012年第5期824-836,共13页
Row sowing is a basic crop sowing method in China,and thus an accurate Bidirectional Reflectance Distribution Function (BRDF) model of row crops is the foundation for describing the canopy bidirectional reflectance ch... Row sowing is a basic crop sowing method in China,and thus an accurate Bidirectional Reflectance Distribution Function (BRDF) model of row crops is the foundation for describing the canopy bidirectional reflectance characteristics and estimating crop ecological parameters.Because of the macroscopically geometric difference,the row crop is usually regarded as a transition between continuous and discrete vegetation in previous studies.Were row treated as the unit for calculating the four components in the Geometric Optical model (GO model),the formula would be too complex and difficult to retrieve.This study focuses on the microscopic structure of row crops.Regarding the row crop as a result of leaves clumped at canopy scale,we apply clumping index to link continuous vegetation and row crops.Meanwhile,the formula of clumping index is deduced theoretically.Then taking leaf as the basic unit,we calculate the four components of the GO model and develop a BRDF model for continuous vegetation,which is gradually extended to the unified BRDF model for row crops.It is of great importance to introduce clumping index into BRDF model.In order to evaluate the performance of the unified BRDF model,the canopy BRDF data collected in field experiment,"Watershed Allied Telemetry Experiment Research (WATER)",from May 30th to July 1st,2008 are used as the validation dataset for the simulated values.The results show that the unified model proposed in this paper is able to accurately describe the non-isotropic characteristics of canopy reflectance for row crops.In addition,the model is simple and easy to retrieve.In general,there is no irreconcilable conflict between continuous and discrete vegetation,so understanding their common and individual characteristics is advantageous for simulating canopy BRDF.It is proven that the four components of the GO model is the basic motivational factor for bidirectional reflectance of all vegetation types. 展开更多
关键词 row crop BRDF CLUMPING clumping index
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