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Ecological Safety Evaluation of Land Use in Ji'an City Based on the Principal Component Analysis 被引量:7
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作者 LIU Fei-yue WAN Shao-kai 《Asian Agricultural Research》 2010年第2期49-52,共4页
According to the ecological safety evaluation index data of land-use change in Ji'an City from 1999 to 2008,positive treatment on selected reverse indices is conducted by Reciprocal Method.Meanwhile,Index Method i... According to the ecological safety evaluation index data of land-use change in Ji'an City from 1999 to 2008,positive treatment on selected reverse indices is conducted by Reciprocal Method.Meanwhile,Index Method is used to standardize the selected indices,and Principal Component Analysis is applied by using year as a unit.FB is obtained,which is related with the ecological safety of land-use change from 1999 to 2008.According to the scientific,integrative,hierarchical,practical and dynamic principles,ecological safety evaluation index system of land-use change in Ji'an City is established.Principal Component Analysis and evaluation model are used to calculate four parameters,including the natural resources safety index of land use,the socio-economic safety indicators of land use,the eco-environmental safety index of land use,and the ecological safety degree of land use in Ji'an City.Result indicates that the ecological safety degree of land use in Ji'an City shows a slow upward trend as a whole.At the same time,ecological safety degree of land-use change is relatively low in Ji'an City with the safety value of 0.645,which is at a weak safety zone and needs further monitoring and maintenance. 展开更多
关键词 Land use Ecological safety principal component Analysis evaluation China
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Application of Principal Component Analysis(PCA)to the Evaluation and Screening of Multiactivity Fungi 被引量:4
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作者 YANG Zonglin SHI Yaqi +5 位作者 LI Pinglin PAN Kanghong LI Guoqiang LI Xianguo YAO Shuo ZHANG Dahai 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第3期763-772,共10页
Continued innovation in screening methodologies remains important for the discovery of high-quality multiactive fungi,which have been of great significance to the development of new drugs.Mangrove-derived fungi,which ... Continued innovation in screening methodologies remains important for the discovery of high-quality multiactive fungi,which have been of great significance to the development of new drugs.Mangrove-derived fungi,which are well recognized as prolific sources of natural products,are worth sustained attention and further study.In this study,118 fungi,which mainly included Aspergillus spp.(34.62%)and Penicillium spp.(15.38%),were isolated from the mangrove ecosystem of the Maowei Sea,and 83.1%of the cultured fungi showed at least one bioactivity in four antibacterial and three antioxidant assays.To accurately evaluate the fungal bioactivities,the fungi with multiple bioactivities were successfully evaluated and screened by principal component analysis(PCA),and this analysis provided a dataset for comparing and selecting multibioactive fungi.Among the 118 mangrove-derived fungi tested in this study,Aspergillus spp.showed the best comprehensive activity.Fungi such as A.clavatonanicus,A.flavipes and A.citrinoterreus,which exhibited high comprehensive bioactivity as determined by the PCA,have great potential in the exploitation of natural products and the development of new drugs.This study demonstrated the first use of PCA as a time-saving,scientific method with a strong ability to evaluate and screen multiactive fungi,which indicated that this method can affect the discovery and development of new drugs. 展开更多
关键词 principal component analysis biological activity FUNGI mangrove ecosystem activity evaluation
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Evaluation and Selection of Sealants and Fillers Using Principal Component Analysis for Cracks in Asphalt Concrete Pavements 被引量:8
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作者 李波 REN Xiaoyu +2 位作者 LI Yanbo MA Weizhong LI Hanlian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第2期408-412,共5页
The objective of this paper was to develop a comprehensive evaluation method and index to evaluate the performance of sealants and fillers for cracks in asphalt concrete pavements using the method of principal compone... The objective of this paper was to develop a comprehensive evaluation method and index to evaluate the performance of sealants and fillers for cracks in asphalt concrete pavements using the method of principal component analysis. The performance experiments including cone penetration, softening point, flow, resilience and tension at low temperature respectively were conducted by reference of ASTM D5329 for eight sealants and fillers often used in China. There by a principal component model was developed and weight of every index was calculated. The experimental results show that there are significantly different performances for sealants and fillers often used in China. Principal component analysis is an objective method that evaluates and selects the performance of sealants and fillers for cracks in asphalt concrete pavements. 展开更多
关键词 road materials asphalt pavement sealants and fillers principal component analysis comprehensive evaluation
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Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model 被引量:4
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作者 张伟伟 宋晓琳 张桂香 《Journal of Central South University》 SCIE EI CAS 2014年第4期1633-1642,共10页
A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and... A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning. 展开更多
关键词 lane departure warning system lane detection lane tracking principal component analysis risk evaluation model ARM-based real-time system
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Comprehensive Evaluation on the Level of Agricultural Economic Development in Hubei Province Based on Principal Component Analysis 被引量:1
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作者 Simian LI 《Asian Agricultural Research》 2020年第8期30-31,39,共3页
[Objectives]Hubei Province has a superior geographical location,and is located in the middle and lower reaches of the Yangtze River,with pleasant climate and abundant natural resources.It is an important province of p... [Objectives]Hubei Province has a superior geographical location,and is located in the middle and lower reaches of the Yangtze River,with pleasant climate and abundant natural resources.It is an important province of population,agriculture and resources in China.[Methods]Based on the data of Statistical Yearbook of Hubei 2018,the agricultural economic indicators of the cities and prefectures in Hubei Province were analyzed with principal component analysis method by using SPSS19.0.[Results]The comprehensive scores and rankings of the agricultural economic development level of the 17 cities and prefectures in Hubei Province were obtained.They were divided into four agricultural development levels.[Conclusions]According to the analysis results,corresponding policy recommendations were put forward to promote the development of agricultural economy in Hubei Province. 展开更多
关键词 Agricultural economic development level principal component analysis Comprehensive evaluation
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Estimation of the Number of Collapsed Houses Damaged by Typhoon Based on Principal Components Analysis and Support Vector Machine 被引量:2
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作者 张新厂 娄伟平 《Meteorological and Environmental Research》 CAS 2010年第4期11-14,共4页
The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of build... The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of buildings were processed by Principal Component Analysis.The key factor was extracted to support input of vector machine model and to build an evaluation model;the historical fitting result kept in line with the fact.In the real evaluation of two typhoons landed in Zhejiang Province in 2008 and 2009,the coincidence of evaluating result and actual value proved the feasibility of this model. 展开更多
关键词 TYPHOON The number of collapsed houses principal components Analysis Support Vector Machine evaluation China
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Predicting the alloying element yield in a ladle furnace using principal component analysis and deep neural network 被引量:8
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作者 Zicheng Xin Jiangshan Zhang +2 位作者 Yu Jin Jin Zheng Qing Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期335-344,共10页
The composition control of molten steel is one of the main functions in the ladle furnace(LF)refining process.In this study,a feasible model was established to predict the alloying element yield using principal compon... The composition control of molten steel is one of the main functions in the ladle furnace(LF)refining process.In this study,a feasible model was established to predict the alloying element yield using principal component analysis(PCA)and deep neural network(DNN).The PCA was used to eliminate collinearity and reduce the dimension of the input variables,and then the data processed by PCA were used to establish the DNN model.The prediction hit ratios for the Si element yield in the error ranges of±1%,±3%,and±5%are 54.0%,93.8%,and98.8%,respectively,whereas those of the Mn element yield in the error ranges of±1%,±2%,and±3%are 77.0%,96.3%,and 99.5%,respectively,in the PCA-DNN model.The results demonstrate that the PCA-DNN model performs better than the known models,such as the reference heat method,multiple linear regression,modified backpropagation,and DNN model.Meanwhile,the accurate prediction of the alloying element yield can greatly contribute to realizing a“narrow window”control of composition in molten steel.The construction of the prediction model for the element yield can also provide a reference for the development of an alloying control model in LF intelligent refining in the modern iron and steel industry. 展开更多
关键词 ladle furnace element yield principal component analysis deep neural network statistical evaluation
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WEB SERVICE SELECTION ALGORITHM BASED ON PRINCIPAL COMPONENT ANALYSIS 被引量:4
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作者 Kang Guosheng Liu Jianxun +1 位作者 Tang Mingdong Cao Buqing 《Journal of Electronics(China)》 2013年第2期204-212,共9页
Existing Web service selection approaches usually assume that preferences of users have been provided in a quantitative form by users. However, due to the subjectivity and vagueness of preferences, it may be impractic... Existing Web service selection approaches usually assume that preferences of users have been provided in a quantitative form by users. However, due to the subjectivity and vagueness of preferences, it may be impractical for users to specify quantitative and exact preferences. Moreover, due to that Quality of Service (QoS) attributes are often interrelated, existing Web service selection approaches which employ weighted summation of QoS attribute values to compute the overall QoS of Web services may produce inaccurate results, since they do not take correlations among QoS attributes into account. To resolve these problems, a Web service selection framework considering user's preference priority is proposed, which incorporates a searching mechanism with QoS range setting to identify services satisfying the user's QoS constraints. With the identified service candidates, based on the idea of Principal Component Analysis (PCA), an algorithm of Web service selection named PCA-WSS (Web Service Selection based on PCA) is proposed, which can eliminate the correlations among QoS attributes and compute the overall QoS of Web services accurately. After computing the overall QoS for each service, the algorithm ranks the Web service candidates based on their overall QoS and recommends services with top QoS values to users. Finally, the effectiveness and feasibility of our approach are validated by experiments, i.e. the selected Web service by our approach is given high average evaluation than other ones by users and the time cost of PCA-WSS algorithm is not affected acutely by the number of service candidates. 展开更多
关键词 principal component Analysis (PCA) Web service selection Quality of Service (QoS) Overall evaluation
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Assessment of Environmental Carrying Capacity Using Principal Component Analysis 被引量:2
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作者 Yinge Liu Junhui Zhang +2 位作者 Shaoxiong Wang Yan Wang Aling Zhao 《Journal of Geoscience and Environment Protection》 2018年第3期54-65,共12页
Regional environmental carrying capacity (ECC) is nonlinear and spatially specific. A hierarchy index system including resources, environmental and socio-economic elements was established using an analytic hierarchy p... Regional environmental carrying capacity (ECC) is nonlinear and spatially specific. A hierarchy index system including resources, environmental and socio-economic elements was established using an analytic hierarchy process. Principal component analysis (PCA) was used to estimate the regional size and differences of environmental carrying capacities. Main information of four principal components, i.e., carrying capacity of resources supply, carrying capacity of environmental quality, carrying capacity of social economy and carrying capacity of infrastructure construction, was extracted. The ECC evaluation value was divided into five levels of lowest carrying capacity, low carrying capacity, medium carrying capacity, high carrying capacity and highest carrying capacity, respectively. The results showed that on the whole ECC was at the medium carrying capacity level. ECC was generally highest in Guanzhong plain, followed by Loess Plateau, and was lowest in Qiba mountain. The carrying capacity of water resources and environmental quality was relatively low, and the infrastructure carrying capacity was highest among the four components. The temporal spatial variation of ECC was closely related to vulnerability of the natural resources and environment in the regions. Verification was proven that PCA was a useful tool when applied to evaluate ECC and reflect the spatial distribution of large-quantity ECC indices on a large regional scale. This study provides a basis for comprehensive understanding of resources, environment and management for regional balanced development. 展开更多
关键词 ENVIRONMENTAL Carrying Capacity principal component Analysis SPATIAL Dif-ference evaluation of INDICATORS
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Application of Principal Component Analysis with SPSS in Water Quality Assessment of Shenzhen Eastern Beach 被引量:1
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作者 彭泰 周连宁 刘念 《Agricultural Science & Technology》 CAS 2014年第4期688-691,共4页
Survey and analysis were conducted on water quality of offshore seas in eastern region of Shenzhen by principal component analysis with SPSS. Then, 8 pollutants indices were then reduced to 5. Based on weighted analys... Survey and analysis were conducted on water quality of offshore seas in eastern region of Shenzhen by principal component analysis with SPSS. Then, 8 pollutants indices were then reduced to 5. Based on weighted analysis of principal component weights, comprehensive scores of different monitored stations were com- puted and sequenced in order to make evaluation on sea quality of eastern region of Shenzhen. 展开更多
关键词 principal components analysis with SPSS Water quality evaluation Eastern region in Shenzhen
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宁南山区新优甘蓝品种品质及挥发性物质研究
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作者 王婷 杜婧含 +4 位作者 张光弟 王江龙 贾毅男 王玉 包文毅 《中国农业科技导报(中英文)》 北大核心 2025年第1期165-180,共16页
为探究不同品种甘蓝常规品质及挥发性物质间的差异,采用生理生化测定方法和气相离子迁移谱(gas chromatography-ion mobility spectrometry,GC-IMS)技术对8个品种甘蓝的外观品质、理化品质及挥发性组分进行检测,并对其品质进行综合评价... 为探究不同品种甘蓝常规品质及挥发性物质间的差异,采用生理生化测定方法和气相离子迁移谱(gas chromatography-ion mobility spectrometry,GC-IMS)技术对8个品种甘蓝的外观品质、理化品质及挥发性组分进行检测,并对其品质进行综合评价。结果表明,叶球质量最大的为‘尼森’;‘探春’的纵径、呼吸强度高于其他品种;横径、维生素C含量最高的为‘晚丰’;‘成功65’可溶性固形物、可滴定酸、可溶性糖含量均最高。8个品种甘蓝中共鉴定出99种挥发性物质,其中醛类、醇类、杂环类物质是甘蓝特征性香气的主要成分;甘蓝的关键挥发性物质主要包括茴香脑、2-异丁基-3-甲基吡嗪、5-甲基-2-呋喃甲醇、芳樟醇、乙酸异戊酯、苯乙醛、2-癸烯醛等。综合评价得分最高的是‘中甘107’,可作为新品种选育及定向育种的优良品种。以上研究结果为甘蓝后续开发利用提供了方向,为宁南山区甘蓝的品质评价、定向育种和生产加工提供理论依据。 展开更多
关键词 甘蓝 采后品质 挥发性物质 主成分分析 综合评价
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6个欧洲李品种果实品质的综合评价
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作者 杨芬芬 王亚铜 +5 位作者 李勤勤 周嫣然 耿文娟 张展闳 樊国全 章世奎 《食品与发酵工业》 CAS 北大核心 2025年第1期280-289,共10页
以6个不同品种欧洲李果实为试材,对其描述性表型、外观数量性表型、不同组织部位内在品质、抗氧化活性等指标进行测定和差异分析,基于相关性分析和主成分分析方法筛选决定品质的关键成分因子,根据得分对6个品种进行排序,为欧洲李品种筛... 以6个不同品种欧洲李果实为试材,对其描述性表型、外观数量性表型、不同组织部位内在品质、抗氧化活性等指标进行测定和差异分析,基于相关性分析和主成分分析方法筛选决定品质的关键成分因子,根据得分对6个品种进行排序,为欧洲李品种筛选及开发利用提供一定理论依据。结果表明,不同品种的果实在品质间存在显著差异(P<0.05)。单果鲜重、果实纵径、横径、侧径最大的是‘总统’;不同组织的物质成分分布不同,果皮的可溶性糖含量、维生素C含量、可滴定酸含量高于果肉;‘法兰西’可溶性糖最高;‘塔城酸梅’可滴定酸最高;果皮、果肉中清除DPPH自由基能力最强的分别是‘理查德早生’、‘女神’;清除羟自由基能力最强的是‘塔城酸梅’。维生素C、类黄酮与果实自由基清除效果呈显著相关性。经主成分分析提取出5个特征值大于1的公因子,综合得分排名前3的是‘女神’、‘法兰西’、‘斯泰勒’。分析结果显示果皮色泽、可溶性固形物含量较高的品种是‘法兰西’、‘女神’,适宜鲜食;单果重、硬度、果皮及果肉L*、可食率等第一主成分得分最高的品种是‘女神’、‘斯泰勒’,适宜长途运输销售;抗氧化活性较高的品种是‘法兰西’、‘总统’、‘女神’、‘塔城酸梅’,适宜加工为抗衰功能的保健产品。 展开更多
关键词 欧洲李 果实品质 抗氧化活性 主成分分析 综合评价
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新疆粳稻耐盐相关性状的主成分分析及综合评价
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作者 康民泰 杜孝敬 +5 位作者 张燕红 文孝荣 唐福森 赵志强 袁杰 王奉斌 《中国稻米》 北大核心 2025年第1期79-83,共5页
为构建一套针对西北粳稻的耐盐综合评价指标体系,并筛选适合新疆盐渍区种植的水稻品种,本研究采用0.5%盐胁迫处理,对18份来自新疆的粳稻材料进行了10项表型指标的测定。在评价过程中,我们采用各单项指标的耐盐系数作为主要评价依据,并... 为构建一套针对西北粳稻的耐盐综合评价指标体系,并筛选适合新疆盐渍区种植的水稻品种,本研究采用0.5%盐胁迫处理,对18份来自新疆的粳稻材料进行了10项表型指标的测定。在评价过程中,我们采用各单项指标的耐盐系数作为主要评价依据,并综合运用了相关分析、主成分分析及聚类分析等多种统计方法,以全面评估这些材料的耐盐性。结果表明,在盐胁迫环境下,参试材料的单穗质量、叶面积、每穗实粒数和每穗总粒数之间表现出显著的相关性;通过主成分分析,我们成功地将盐胁迫下的10项指标简化为4个相互独立且信息量丰富的主成分,这4个主成分的累计贡献率达76.19%;依据参试材料的综合评价值D进行聚类分析,最终将18份参试材料划分为三类:不耐盐材料,占比11.11%;中等耐盐材料,占比61.11%;耐盐材料,占比27.78%,具体包括SD-12、SD-17、SD-16、SD-13、SD-15。 展开更多
关键词 粳稻 耐盐性 主成分分析 聚类分析 综合评价
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基于最小数据集的云南橡胶林土壤质量评价
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作者 张和芬 孙瑞 +3 位作者 杨川 张盈盈 符庆茂 吴志祥 《西北林学院学报》 北大核心 2025年第1期59-69,103,共12页
为了评估云南橡胶林土壤质量,以云南省河口、瑞丽、景洪3个典型橡胶产区5个不同林龄段(幼、中、近熟、成熟和过熟林)橡胶林土壤为研究对象,采集并分析0~10、11~20 cm和21~40 cm深度的土壤样品。将土壤容重、含水量、硝态氮、铵态氮、全... 为了评估云南橡胶林土壤质量,以云南省河口、瑞丽、景洪3个典型橡胶产区5个不同林龄段(幼、中、近熟、成熟和过熟林)橡胶林土壤为研究对象,采集并分析0~10、11~20 cm和21~40 cm深度的土壤样品。将土壤容重、含水量、硝态氮、铵态氮、全氮、速效磷、全磷、速效钾、全钾、pH、有机质、脲酶、纤维素酶、过氧化氢酶、蔗糖转化酶等作为评价指标,运用主成分分析、相关性分析,结合Norm值筛选,构建土壤质量综合指数(SQI),对土壤质量进行定量评价。结果表明,土壤容重、硝态氮、全氮、全磷、全钾、有机质、脲酶7项指标进入最小数据集;SQI-TDS的范围0.29~0.56,平均值0.39,变异系数14.67%;SQI-MDS的最小值0.20,最大值0.53,平均值0.34,变异系数18.88%;相关性分析显示,2种评价结果具有较好的相关性。土壤质量综合指数随着定植年限的增长呈略微先降低后增加的趋势;3个植胶区土壤质量以三级和四级为主,土壤质量排序为景洪>河口>瑞丽。 展开更多
关键词 土壤质量评价 主成分分析 最小数据集 橡胶林 云南
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不同用途稻米品质指标体系构建与特征性指标筛选
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作者 朱翠玲 季圣阳 +3 位作者 刘彦君 宋华欣 邵雅芳 陆柏益 《食品工业科技》 北大核心 2025年第4期258-269,共12页
以稻米为研究对象,梳理品质评价指标、评价方法及依据,构建基于不同用途的稻米品质指标体系,同时分析不同优势产区和主栽品种稻米品质差异,筛选基于不同用途稻米的特征性品质指标,以推动稻米的品质评价走向规范。通过Delphi评价法和G1... 以稻米为研究对象,梳理品质评价指标、评价方法及依据,构建基于不同用途的稻米品质指标体系,同时分析不同优势产区和主栽品种稻米品质差异,筛选基于不同用途稻米的特征性品质指标,以推动稻米的品质评价走向规范。通过Delphi评价法和G1法从基本指标中筛选主要品质指标,构建品质指标体系。测定262个稻米样品的主要品质指标成分差异。采用相关性分析、主成分分析、多元线性回归分析等方法筛选出不同用途稻米品质的特征性指标。结果表明:适用于食用商品稻米的优势产区为东北水稻(辽宁、吉林)、长江流域水稻(江苏),优质品种为沈农511、吉粳816和南粳46,其特征性指标为食味值、蛋白质和气味;米粉加工用稻米的优势产区为东南沿海水稻(广东、广西、浙江)及长江流域水稻(湖南),优质品种为中早39、湘早籼45号、珍桂和春两优61,其特征性指标为峰值粘度、最终粘度、蛋白质含量及直链淀粉含量;发酵制品用稻米的优势产区为东南沿海水稻(浙江)及长江流域水稻(江西、湖南),优质品种为中早39、中早33、湘早籼45号,其特征性指标为直链淀粉含量、糖化性能和还原糖含量。本文的研究结果为不同用途稻米的品质评价提供了理论基础和科学依据。 展开更多
关键词 稻米 品质评价 主成分分析 特征性指标 指标筛选
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基于ROAV法与PCA-TOPSIS法冰葡萄酒香气质量综合评价
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作者 张杨 曲绎霖 +2 位作者 孙永德 孔维府 李红娟 《中国酿造》 北大核心 2025年第1期258-268,共11页
该研究以四款代表性国产冰酒(编号为1号~4号)为研究对象,采用顶空-固相微萃取(HS-SPME)结合气质联用(GC-MS)技术测定冰酒的挥发性香气成分,并构建主成分分析(PCA)-优劣解距离法(TOPSIS)模型对冰酒香气品质进行分析评价。结果表明,四款... 该研究以四款代表性国产冰酒(编号为1号~4号)为研究对象,采用顶空-固相微萃取(HS-SPME)结合气质联用(GC-MS)技术测定冰酒的挥发性香气成分,并构建主成分分析(PCA)-优劣解距离法(TOPSIS)模型对冰酒香气品质进行分析评价。结果表明,四款冰酒共检测出118种挥发性香气成分,其中脂肪酸乙酯类18种、乙酸酯类8种、其他酯类24种、醇类13种、萜烯类12种、降异戊二烯衍生物4种、酸类5种、醛酮类9种、芳香族化合物15种、其他类10种;四款冰酒中香气成分的种类与含量差别显著。通过相对气味活度值(ROAV)筛选出22种重要香气物质(ROAV>0.1),10种关键香气物质(ROAV>1)。相关性结果表明,辛酸乙酯与苯乙醛呈显著负相关(P<0.05)、与大马士酮呈极显著负相关(P<0.01);大马士酮与苯乙醛呈显著正相关(P<0.05)、与癸酸乙酯和辛酸乙酯呈极显著负相关(P<0.01)。PCA-TOPSIS得出四款冰酒的香气评价结果Si(相对接近度)依次为0.804(4号)>0.572(2号)>0.411(1号)>0.229(3号),表明4号冰酒香气品质最优。 展开更多
关键词 冰葡萄酒 香气质量评价 相对气味活度值 主成分分析法 优劣解距离法
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不同苦荞种质资源耐荫性评价及鉴定指标的筛选
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作者 张鲜 赵少迪 +5 位作者 胡传伟 吴晓梅 王秋宝 刘月贤 田洪岭 张丽君 《核农学报》 CAS 北大核心 2025年第2期223-232,I0001-I0004,共14页
为建立耐荫性评价模型以筛选苦荞耐荫种质资源,以60份苦荞种质资源为材料,采用田间试验,设置遮荫和自然光两种处理,测定株高等9个形态结构指标和超氧化物歧化酶(SOD)活性等6个生理指标,计算各指标的耐荫系数。采用多元统计分析方法对苦... 为建立耐荫性评价模型以筛选苦荞耐荫种质资源,以60份苦荞种质资源为材料,采用田间试验,设置遮荫和自然光两种处理,测定株高等9个形态结构指标和超氧化物歧化酶(SOD)活性等6个生理指标,计算各指标的耐荫系数。采用多元统计分析方法对苦荞耐荫性进行综合评价及耐荫指标的筛选。结果表明,15个指标的耐荫系数存在不同程度的变异,变异系数范围为7.87%~85.84%,除丙二醛(MDA)含量、过氧化物酶(POD)和过氧化氢酶(CAT)活性外,其他各单项指标间均存在一定的相关性。通过主成分分析,从15个指标的耐荫系数中提取了5个主成分,其累计方差贡献率达69.307%。利用隶属函数分析法计算60份苦荞种质资源的综合评价值(D),并在此基础上采用聚类分析将种质资源分为耐荫型、中度耐荫型和敏感型3类。进一步利用逐步回归分析建立最优线性回归方程D=-0.176+0.115X_(1)+0.313X_(5)+0.140X_(6)+0.057X_(7)+0.176X_(10)-0.015X_(13),筛选出株高、主茎粗第五节、主茎粗第八节、单株粒数、始花期叶绿素相对含量(SPAD)、POD活性共6个耐荫性鉴定指标。本研究结果为苦荞耐荫抗倒伏种质资源鉴定及新品种选育提供了参考依据。 展开更多
关键词 苦荞 耐荫性评价 主成分分析 聚类分析 逐步回归分析
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31个鲜食型黄瓜品种品质性状的综合评价
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作者 张越 张文浩 +2 位作者 赵瑞琦 陈文良 张明科 《中国蔬菜》 北大核心 2025年第1期98-106,共9页
为建立一套实用的鲜食型黄瓜品质评价体系,以征集的3个生态类型共计31个黄瓜品种为试材,开展风味感官指标评价,并结合营养品质指标,利用主成分分析方法进行综合评价。结果表明:在华北型品种中,蔬研翠玉风味感官评价最佳,综合评分30.83;... 为建立一套实用的鲜食型黄瓜品质评价体系,以征集的3个生态类型共计31个黄瓜品种为试材,开展风味感官指标评价,并结合营养品质指标,利用主成分分析方法进行综合评价。结果表明:在华北型品种中,蔬研翠玉风味感官评价最佳,综合评分30.83;在华南型品种中,唐山秋黄瓜风味感官评价最佳,综合评分30.50;在欧洲温室型品种中,绿园幸福风味感官评价最佳,综合评分30.65。利用主成分分析法,得到5个主成分,涵盖了77.612%的原始信息,通过建立的鲜食型品质评价综合模型F=0.315F_(1)+0.265F_(2)+0.163F_(3)+0.145F_(4)+0.112F_(5),获得了31个黄瓜品种的综合得分。华南型品种天天摘、华北型品种蔬研翠玉、欧洲温室型品种拇指水果黄瓜在其各自生态类型中得分最高,可以作为不同生态类型的鲜食型黄瓜品种进行选择应用。研究结果为鲜食型黄瓜的品种选育及品质评价提供了理论依据和技术支持。 展开更多
关键词 黄瓜 鲜食型 主成分分析 品质 综合评价
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Eco-environmental Quality Evaluation of Coal City Based on AHP-PCA Model 被引量:17
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作者 李峰 刘小阳 +1 位作者 于雪涛 刘文龙 《矿业安全与环保》 北大核心 2017年第5期103-106,110,共5页
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基于指纹图谱结合化学模式识别的精天颗粒质量评价
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作者 赵伟 陈树和 +3 位作者 闫斌 郑琼芳 张伟欣 巴元明 《中国药房》 北大核心 2025年第3期300-305,共6页
目的 建立精天颗粒的超高效液相色谱(UPLC)指纹图谱,并结合化学模式识别法评价其质量。方法 以Luna~?Omega Polar C18(150 mm×2.1 mm,1.6μm)为色谱柱,以乙腈-0.2%磷酸溶液为流动相进行梯度洗脱,流速为0.2 mL/min,柱温为30℃,检测... 目的 建立精天颗粒的超高效液相色谱(UPLC)指纹图谱,并结合化学模式识别法评价其质量。方法 以Luna~?Omega Polar C18(150 mm×2.1 mm,1.6μm)为色谱柱,以乙腈-0.2%磷酸溶液为流动相进行梯度洗脱,流速为0.2 mL/min,柱温为30℃,检测波长为265 nm。以16号峰为参照峰,通过《中药色谱指纹图谱相似度评价系统(2012版)》建立精天颗粒的UPLC指纹图谱,指认共有峰并进行相似度评价,同时确认每个共有峰的饮片归属。运用化学模式识别方法中的层次聚类分析(HCA)、主成分分析(PCA)对13批样品(S1~S13)进行分类,并采用正交偏最小二乘-判别分析(OPLS-DA)来识别导致不同批次样品间差异的关键性成分。结果 所建UPLC方法精密度、重复性、稳定性的RSD均不大于4.4%。在13批精天颗粒指纹图谱中共标定出25个共有峰;通过与对照指纹图谱比对,指认了其中10个共有峰,分别为3号峰(5-羟甲基糠醛)、5号峰(红景天苷)、8号峰(绿原酸)、15号峰(肉桂酸)、19号峰(芦荟大黄素)、20号峰(甘草酸铵)、21号峰(大黄酸)、23号峰(大黄素)、24号峰(甘草次酸)、25号峰(大黄酚)。13批样品指纹图谱的相似度为0.955~0.996。HCA结果显示,13批样品可聚为3类,其中S1、S5、S7、S11~S13为一类,S4、S6为一类,S2、S3、S8~S10为一类。PCA结果显示,主成分1~7的累计方差贡献率为92.666%。OPLS-DA进一步确定了13个差异性成分,这些成分主要来源于酒黄精、红景天、熟大黄和炙甘草等。结论 所建立的精天颗粒UPLC指纹图谱方法简便、稳定、重复性良好,结合化学模式识别方法能有效揭示精天颗粒不同批次间的整体质量差异。方中酒黄精、红景天、熟大黄、穿山龙、猪苓、桂枝、炙甘草的质量是影响精天颗粒整体质量的关键。 展开更多
关键词 精天颗粒 指纹图谱 超高效液相色谱法 层次聚类分析 主成分分析 正交偏最小二乘-判别分析 质量评价
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