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Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat
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作者 Zhikai Cheng Xiaobo Gu +5 位作者 Yadan Du Zhihui Zhou Wenlong Li Xiaobo Zheng Wenjing Cai Tian Chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1523-1540,共18页
In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge m... In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching. 展开更多
关键词 mulched winter wheat machine learning fuzzy comprehensive evaluation comprehensive growth evaluation index unmanned aerial vehicle
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I-DCGAN and TOPSIS-IFP:A simulation generation model for radiographic flaw detection images in light alloy castings and an algorithm for quality evaluation of generated images
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作者 Ming-jun Hou Hao Dong +7 位作者 Xiao-yuan Ji Wen-bing Zou Xiang-sheng Xia Meng Li Ya-jun Yin Bao-hui Li Qiang Chen Jian-xin Zhou 《China Foundry》 SCIE EI CAS CSCD 2024年第3期239-247,共9页
The intelligent detection technology driven by X-ray images and deep learning represents the forefront of advanced techniques and development trends in flaw detection and automated evaluation of light alloy castings.H... The intelligent detection technology driven by X-ray images and deep learning represents the forefront of advanced techniques and development trends in flaw detection and automated evaluation of light alloy castings.However,the efficacy of deep learning models hinges upon a substantial abundance of flaw samples.The existing research on X-ray image augmentation for flaw detection suffers from shortcomings such as poor diversity of flaw samples and low reliability of quality evaluation.To this end,a novel approach was put forward,which involves the creation of the Interpolation-Deep Convolutional Generative Adversarial Network(I-DCGAN)for flaw detection image generation and a comprehensive evaluation algorithm named TOPSIS-IFP.I-DCGAN enables the generation of high-resolution,diverse simulated images with multiple appearances,achieving an improvement in sample diversity and quality while maintaining a relatively lower computational complexity.TOPSIS-IFP facilitates multi-dimensional quality evaluation,including aspects such as diversity,authenticity,image distribution difference,and image distortion degree.The results indicate that the X-ray radiographic images of magnesium and aluminum alloy castings achieve optimal performance when trained up to the 800th and 600th epochs,respectively.The TOPSIS-IFP value reaches 78.7%and 73.8%similarity to the ideal solution,respectively.Compared to single index evaluation,the TOPSIS-IFP algorithm achieves higher-quality simulated images at the optimal training epoch.This approach successfully mitigates the issue of unreliable quality associated with single index evaluation.The image generation and comprehensive quality evaluation method developed in this paper provides a novel approach for image augmentation in flaw recognition,holding significant importance for enhancing the robustness of subsequent flaw recognition networks. 展开更多
关键词 light alloy casting flaw detection image generator DISCRIMINATOR comprehensive evaluation index
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Comprehensive Evaluation of Distributed PV Grid-Connected Based on Combined Weighting Weights and TOPSIS-RSR Method
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作者 Yue Yang Jiarui Zheng +2 位作者 Long Cheng Yongnan Zhu Hao Wu 《Energy Engineering》 EI 2024年第3期703-728,共26页
To effectively quantify the impact of distributed photovoltaic(PV)access on the distribution network,this paper proposes a comprehensive evaluation method of distributed PV grid connection combining subjective and obj... To effectively quantify the impact of distributed photovoltaic(PV)access on the distribution network,this paper proposes a comprehensive evaluation method of distributed PV grid connection combining subjective and objective combination of assignment and technique for order preference by similarity to an ideal solution(TOPSIS)—rank sum ratio(RSR)(TOPSIS-RSR)method.Based on the traditional distribution network evaluation system,a comprehensive evaluation system has been constructed.It fully considers the new development requirements of distributed PV access on the environmental friendliness and absorptive capacity of the distribution grid and comprehensively reflects the impact of distributed PV grid connection.The analytic hierarchy process(AHP)was used to determine the subjective weights of the primary indicators,and the Spearman consistency test was combined to determine the weights of the secondary indicators based on three objective assignment methods.The subjective and objective combination weights of each assessment indicator were calculated through the principle of minimum entropy.Calculate the distance between the indicators to be evaluated and the positive and negative ideal solutions,the relative closeness ranking,and qualitative binning by TOPSIS-RSR method to obtain the comprehensive evaluation results of different scenarios.By setting up different PV grid-connected scenarios and utilizing the IEEE33 node simulation algorithm,the correctness and effectiveness of the proposed subject-object combination assignment and integrated assessment method are verified. 展开更多
关键词 Distributed PV grid-connected comprehensive evaluation evaluation indicator system combined subjective and objective empowerment TOPSIS-RSR method
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Spatio-temporal Evaluation of Multi-scale Cultivated Land System Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China
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作者 WANG Yue JIANG Yuting ZHU Guoxu 《Chinese Geographical Science》 SCIE CSCD 2024年第1期168-180,共13页
It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cult... It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food security.It is urgent to evaluate the CLSR at multiple spatio-temporal scales.This study took Liaoning Province in the black soil region of Northeast China as an example.Based on the resilience theory,this study constructed the CLSR evaluation system from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to 2019.The results showed that:1) the time series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) The CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) There were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,respectively.In addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the city-scale.The feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the city-scale.The results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment. 展开更多
关键词 cultivated land system resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning Province China
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Comprehensive Evaluation of Flower Border Application Value of New and Superior Plants in Hefei Area
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作者 MENG Yi ZHAO Zhiyan +1 位作者 LIANG Tingwu LU Zhaoliang 《Journal of Landscape Research》 2024年第2期69-71,76,共4页
An analytic hierarchy process(AHP)was employed to assess the applicability of 18 new and superior varieties of flowers in Hefei City flower border applications.A total of 12 indicators were selected from three distinc... An analytic hierarchy process(AHP)was employed to assess the applicability of 18 new and superior varieties of flowers in Hefei City flower border applications.A total of 12 indicators were selected from three distinct aspects of adaptability,ornamental characteristics and use traits,in order to establish a comprehensive evaluation model.The results demonstrate that grade I(J≥2.685)exhibits excellent application value,encompassing six species of plants,such asHydrangeamacrophylla‘Endless Summer’;grade II(2.684≤J≤2.420)is also of notable application value,encompassing five species of plants,such asCallistemonrigidus;grade III(2.419≤J≤2.615)is of average application value,including five species of plants,such asCrocosmiacrocosmiflora;grade IV(J≤2.16)is of relatively poor application value.The evaluation results may be utilized as a theoretical reference for the promotion of new and superior varieties in the flower border of Hefei. 展开更多
关键词 Analytic hierarchy process(AHP) New and superior variety Application value Comprehensive evaluation
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Comprehensive Benefit Evaluation of SZ Distributed Photovoltaic Power Generation Project Based on AHP-Matter-Element Extension Model
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作者 Shuli Jing 《Journal of Electronic Research and Application》 2024年第1期60-68,共9页
With the introduction of the“dual carbon goals,”there has been a robust development of distributed photovoltaic power generation projects in the promotion of their construction.As part of this initiative,a comprehen... With the introduction of the“dual carbon goals,”there has been a robust development of distributed photovoltaic power generation projects in the promotion of their construction.As part of this initiative,a comprehensive and systematic analysis has been conducted to study the overall benefits of photovoltaic power generation projects.The evaluation process encompasses economic,technical,environmental,and social aspects,providing corresponding analysis methods and data references.Furthermore,targeted countermeasures and suggestions are proposed,signifying the research’s importance for the construction and development of subsequent distributed photovoltaic power generation projects. 展开更多
关键词 Distributed photovoltaic power generation Comprehensive benefits evaluation
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Analysis of Landscape Vitality of Historical and Cultural Blocks Based on AHPFuzzy Comprehensive Evaluation Method:A Case Study of Daopashi Street in Anqing City 被引量:1
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作者 YANG Xinru LIU Hongyun +1 位作者 LI Tianjiao WANG Xingyi 《Journal of Landscape Research》 2023年第3期59-62,66,共5页
Historical and cultural blocks are witnesses of history and inheritors of culture. As one of the main spaces for outdoor interaction in historical and cultural blocks, the improvement of its vitality is of great signi... Historical and cultural blocks are witnesses of history and inheritors of culture. As one of the main spaces for outdoor interaction in historical and cultural blocks, the improvement of its vitality is of great significance for the improvement of residential environment and the better inheritance of history and culture. Taking Daopashi Street in Anqing City as an example, an evaluation model of landscape spatial vitality of historical and cultural blocks was constructed from three aspects of viewing function, store status and service facilities, and analytic hierarchy process was used to determine the index weight and vaguely evaluate the landscape spatial vitality of historical and cultural blocks. The results show that through the comparison of weight, architectural style(0.317), the practicability of service facilities(0.168) and plant landscape(0.165) had a significant impact on the landscape spatial vitality of historical and cultural blocks,and the landscape spatial vitality of historical and cultural blocks in Daopashi Street in Anqing City was at a good level. 展开更多
关键词 Analytic hierarchy process Fuzzy comprehensive evaluation method Historical and cultural blocks Landscape vitality
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Operation State of theWind Turbine Pitch System Based on Fuzzy Comprehensive Evaluation
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作者 Anfeng Zhu Qiancheng Zhao +2 位作者 LinGui Tianlong Yang Xuebing Yang 《Energy Engineering》 EI 2023年第2期425-444,共20页
To ensure wind turbine(WT)safe operations and improve the utilization rate of wind energy,effective evaluation of the operation state of the pitch system is critical.Therefore,a new method was proposed to evaluate the... To ensure wind turbine(WT)safe operations and improve the utilization rate of wind energy,effective evaluation of the operation state of the pitch system is critical.Therefore,a new method was proposed to evaluate the operation state of the pitch system of WT based on fuzzy comprehensive evaluation.Firstly,based on SCADA data,the working state of the pitch system under rated power state and power state of WT were analyzed.Secondly,through the analysis of characteristic parameters and physical mechanism of the pitch system,the consistency principle of characteristic parameters,the stability principle of power under rated state,and the stability principle of blade angle underpowered state were obtained.Next,based on the aforementioned principles,the evaluation indexes were established,and the fuzzy comprehensive evaluation method was used to establish the operation state evaluation model of the pitch system under rated power state and under power state of the WT.Finally,an example was provided to verify the effectiveness of the method.The evaluation model established in this study can be used as a technical reference for the online monitoring of WT pitch systems to ensure the safe and stable operation of WTs. 展开更多
关键词 Wind turbine(WT) pitch system fuzzy comprehensive evaluation state evaluation
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Construction and Innovation of Comprehensive Evaluation Means of PBL+OBE-based Software Engineering Practical Courses
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作者 Yixian Liu Jun Guo Dongming Chen 《计算机教育》 2023年第12期106-113,共8页
Software engineering is an engineering discipline that guides software developers to carry out software development,software maintenance,and software management.The traditional evaluation methods of software engineeri... Software engineering is an engineering discipline that guides software developers to carry out software development,software maintenance,and software management.The traditional evaluation methods of software engineering courses do not highlight the training goal of outcomebased education(OBE).This paper systematically studies the evaluation methods for practical courses in software engineering from three aspects:course evaluation guidelines,course evaluation methods and course evaluation effects;establishes a comprehensive,scientific,and objective system of course evaluation;effectively measures students’learning effect;promotes teachers to continuously improve the teaching process;and thus improves the teaching quality of software engineering courses.Besides the general approach,this paper also takes software project construction practice as an example to demonstrate the effect of the proposed approach. 展开更多
关键词 Comprehensive evaluation PBL OBE Software engineering Practical coursess
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Self-reported physical functioning,cardiometabolic health conditions, and healthcare utilization patterns in Million Veteran Program enrollees with Traumatic Brain Injury Screening and Evaluation Program data
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作者 Alexandra L.Clark Makenna B.McGill +3 位作者 Erin D.Ozturk David M.Schnyer Catherine Chanfreau‑Cofnier Victoria C.Merritt 《Military Medical Research》 SCIE CAS CSCD 2023年第5期587-598,共12页
Background Examining the health outcomes of veterans who have completed the United States Veterans Health Administration’s(VHA’s)Traumatic Brain Injury(TBI)Screening and Evaluation Program may aid in the refinement ... Background Examining the health outcomes of veterans who have completed the United States Veterans Health Administration’s(VHA’s)Traumatic Brain Injury(TBI)Screening and Evaluation Program may aid in the refinement and improvement of clinical care initiatives within the VHA.This study compared self-reported physical functioning,cardiometabolic health conditions,and health care utilization patterns in Million Veteran Program enrollees with TBI Screening and Evaluation Program data(collected between 2007 and 2019),with the goal of enhancing understanding of potentially modifiable health conditions in this population.Methods In this observational cohort study,veterans(n=16,452)were grouped based on the diagnostic outcome of the TBI Screening and Evaluation Program:1)negative TBI screen(Screen^(-));2)positive TBI screen but no confirmed TBI diagnosis[Screen^(+)/Comprehensive TBI Evaluation(CTBIE)^(-)];or 3)positive TBI screen and confirmed TBI diagnosis(Screen^(+)/CTBIE^(+)).Chi-square tests and analysis of covariance were used to explore group differences in physical functioning,cardiometabolic health conditions,and health care utilization patterns,and logistic regressions were used to examine predictors of Screen^(+/-)and CTBIE^(+/-)group status.Results The results showed that veterans in the Screen^(+)/CTBIE^(-)and Screen^(+)/CTBIE^(+)groups generally reported poorer levels of physical functioning(P’s<0.001,np2=0.02 to 0.03),higher rates of cardiometabolic health conditions(P’s<0.001,φ=0.14 to 0.52),and increased health care utilization(P’s<0.001,φ=0.14 to>0.5)compared with the Screen-group;however,health outcomes were generally comparable between the Screen^(+)/CTBIE^(-)and Screen^(+)/CTBIE^(+)groups.Follow-up analyses confirmed that while physical functioning,hypertension,stroke,healthcare utilization,and prescription medication use reliably distinguished between the Screen-and Screen^(+)groups(P’s<0.02,OR’s 0.78 to 3.38),only physical functioning distinguished between the Screen^(+)/CTBIE^(-)and Screen^(+)/CTBIE^(+)groups(P<0.001,OR 0.99).Conclusions The findings suggest that veterans who screen positive for TBI,regardless of whether they are ultimately diagnosed with TBI,are at greater risk for negative health outcomes,signifying that these veterans represent a vulnerable group that may benefit from increased clinical care and prevention efforts. 展开更多
关键词 Traumatic brain injury(TBI)screen Comprehensive TBI evaluation(CTBIE) Health outcomes Cardiometabolichealth Veterans Million Veteran Program(MVP)
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Comprehensive Evaluation of Wheat Varieties in Southern Shandong Province by DTOPSIS Based on Entropy Weighting
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作者 Jing WANG Lingguo KONG +4 位作者 Baoqiang LI Long LI Guoqiang FAN Zhongxin ZHOU Qingfeng FAN 《Asian Agricultural Research》 2023年第7期39-44,共6页
[Objectives] To screen a new wheat variety suitable for planting in southern Shandong Province. [Methods] The DTOPSIS based on entropy weighting was used to comprehensively evaluate 9 traits of 19 wheat varieties plan... [Objectives] To screen a new wheat variety suitable for planting in southern Shandong Province. [Methods] The DTOPSIS based on entropy weighting was used to comprehensively evaluate 9 traits of 19 wheat varieties planted in southern Shandong Province. [Results] The weight of each indicator from low to high was growth period<yield<bulk density<plant height<effective panicle<basic seedling<1 000-grain weight<heading rate<number of grains per panicle. The Ci value of 6 varieties were greater than 0.5, specifically, 0.922 1 for Shannong HH126, 0.868 for DK171, 0.851 5 for Hemai 179, 0.719 6 for Feida 6, 0.696 7 for Jinlai 36 and 0.523 2 for Yannong 301. [Conclusions] The comprehensive traits of these six wheat varieties are good, and they are suitable for planting in southern Shandong Province. 展开更多
关键词 WHEAT Comprehensive evaluation DTOPSIS ENTROPY
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Comprehensive Evaluation of New Maize Varieties for Grain and Fodder Based on Membership Function Method
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作者 Chenglin ZOU Qiongxiang LIN +6 位作者 Kaijian HUANG Ruining ZHAI Meng YANG Aihua HUANG Runxiu MO Xinxing WEI Yanfen HUANG 《Agricultural Biotechnology》 CAS 2023年第2期5-10,共6页
To screen new maize(Zea mays L.)varieties suitable for food and fodder dual-purpose in Du'an Yao Autonomous County of Guangxi,the agronomic characters,yield and quality indexes of 12 new maize varieties were measu... To screen new maize(Zea mays L.)varieties suitable for food and fodder dual-purpose in Du'an Yao Autonomous County of Guangxi,the agronomic characters,yield and quality indexes of 12 new maize varieties were measured,and the correlation between various indexes were analyzed,and the comprehensive performance of tested varieties was evaluated by membership function method.The results showed that Guidan 671 had the highest grain yield and whole-plant biomass at 10908 and 49965 kg/hm^(2),respectively,and the second was Zhaoyu 215 with a grain yield and whole-plant biomass of 10086 and 47175 kg/hm^(2),respectively.Grain yield was highly significantly positively correlated with ear diameter and 100-grain weight(P<0.01),and significantly correlated with whole-plant biomass,starch content,ear length and grain number per row(P<0.05);and the whole-plant biomass was highly significantly correlated with the number of grains per row(P<0.01),and significantly correlated with starch content,panicle length,plant height and panicle height(P<0.05).The comprehensive performance scores of the tested varieties from high to low were Guidan 671,Zhaoyu 215,Guidan 669,Guidan 6208,Guidan 666,Guidan 6205,Guidan 660,Guidan 6203,Guidan 6206,Guidan 162,Guidan 668 and Guidan 673.According to the values of membership function and combined with various indexes,Guidan 671 and Zhaoyu 215 had good comprehensive performance,and could be used as the first choice for food and fodder dual-purpose maize varieties in Du'an Yao Autonomous County. 展开更多
关键词 MAIZE Food and feed dual-purpose Membership function method Comprehensive evaluation
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Evaluation of Water Resources Carrying Capacity in Gansu Section of Yellow River Basin Based on Fuzzy Comprehensive Evaluation Model
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作者 Shuanbao LIN 《Meteorological and Environmental Research》 CAS 2023年第4期42-45,49,共5页
As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically ev... As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically evaluate the water resources carrying capacity is the premise to improve the regional water resources carrying capacity and ensure the regional water security.The Gansu section of the Yellow River basin is an important water conservation and recharge area.Whether the water resources in this area can ensure the normal operation of the ecosystem and whether it can carry the sustainable development of social economy is the key to realize the high-quality development of the Yellow River basin.In this study,from the three dimensions of water consumption per capita,water consumption of 10000 yuan GDP and ecological water use rate,by constructing the evaluation index system and index grading standard of water resources carrying capacity,the fuzzy comprehensive evaluation model was used to evaluate the water resources carrying capacity of Gansu section of the Yellow River Basin,in order to provide theoretical decision-making basis for the comprehensive development,utilization and planning management of water resources in Gansu section of the Yellow River basin and even the whole basin,and help the high-quality development of the Yellow River basin. 展开更多
关键词 Fuzzy comprehensive evaluation model Water resources carrying capacity evaluation Yellow River basin Gansu section
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Evaluation of Productive Plant Landscapes in Cold Regions Based on a Multiple Cropping Model
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作者 Wu Zhi-heng Zhang Jia-xin +2 位作者 Zhu Xuan-bo Pan Sheng-kai Yan Yong-qing 《Journal of Northeast Agricultural University(English Edition)》 2023年第4期43-52,共10页
Four varieties of each rapeseed and buckwheat were planted in different sowing periods to explore a variety of planting patterns.A theoretical foundation was provided for the innovative application of cold region prod... Four varieties of each rapeseed and buckwheat were planted in different sowing periods to explore a variety of planting patterns.A theoretical foundation was provided for the innovative application of cold region productive plant landscapes.The analytic hierarchy process was employed to develop a model for the evaluation of multiple cropping systems.A comprehensive evaluation was conducted to study 10 indicators in plant type,flower color,flowering period,flower volume,branch coverage,plot average yield,number of grains per plant,yield per plant,thousand-grain quality and ecological adaptability in four different varieties of each rapeseed and buckwheat.The results indicated that flower color,ecological adaptability,plot average yield and flower volume were the most important indicators for the value of productive plant landscapes in cold regions.Concerning the sowing period,the optimal combination of varieties and planting times were March 31 for Qingza No.5(rapeseed)and July 18 for Xinong T1211(buckwheat). 展开更多
关键词 multiple cropping model RAPESEED BUCKWHEAT analytic hierarchy process comprehensive evaluation
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基于多元统计分析评价不同茶树品种的绿茶适制性 被引量:1
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作者 王欢欢 袁丽萍 +7 位作者 雷震东 杨淑雅 李玉川 周敬涛 覃信雪 余志 倪德江 陈玉琼 《食品科学》 EI CAS CSCD 北大核心 2024年第3期9-15,共7页
采用主成分分析和多元线性回归分析法考察不同茶区优选区域适制茶树品种的绿茶适制性。本研究以种植于同一区域的63个茶树品种鲜叶为原料,按同一加工工艺加工成烘青绿茶,分析其感官品质、主要理化品质(茶多酚、游离氨基酸、水浸出物和... 采用主成分分析和多元线性回归分析法考察不同茶区优选区域适制茶树品种的绿茶适制性。本研究以种植于同一区域的63个茶树品种鲜叶为原料,按同一加工工艺加工成烘青绿茶,分析其感官品质、主要理化品质(茶多酚、游离氨基酸、水浸出物和叶绿素)和色度值(L*、a*、b*),结合主成分分析和多元线性回归分析,评价供试品种的绿茶适制性及其主要影响因子。结果表明,不同品种绿茶叶绿素含量的变异系数最大(26.7%),其次是干茶色度值a*值(22.2%)、汤色(17.1%)和干茶色泽评分(16.2%)。各指标相关性分析表明,茶多酚含量与干茶色泽、汤色和叶底色泽之间,干茶叶绿素含量、|a*|值、b*值与干茶色泽之间,干茶叶绿素含量、|a*|与叶底色泽之间,干茶|a*|值、b*值与汤色之间极显著相关(P<0.01)。主成分分析结果表明,前5个主成分贡献率达76.895%,第1主成分贡献率为31.918%,主要指向色泽品质。通过前5个主成分构建评价模型,得到排名前10的品种包括:中茶108、乌牛早、平阳特早、蒙山9号、薮北种、福鼎大白、鸠坑16号、福鼎大毫、茂绿、龙井43。以主要理化品质和感官评价总分为对象进行多元线性回归分析,得到回归函数为:Y=68.668+5.174x,其中Y为感官评分总分,x为|a*|值,R2为0.313(P<0.001)。以此函数得到排名前10的品种与主成分分析结果高度一致,表明a*值是评定绿茶适制品种的重要指标,可作为绿茶适制品种筛选的重要依据。 展开更多
关键词 绿茶 茶树品种 适制性 综合评价
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协调公平与效率的“四水四定”研究Ⅰ:方法与模型 被引量:1
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作者 游进军 贾玲 +2 位作者 杨朝晖 汪林 王婷 《水利学报》 EI CSCD 北大核心 2024年第2期158-166,共9页
针对水资源刚性约束落地缺抓手的问题,按照以水定发展、协调定规模的理念,提出“四水四定”的分析思路和控制指标,厘清各类发展目标与水资源利用的协调关系。以公平为社会目标,以效益为经济目标,提出“尊重现状、保障刚需、效率驱动、... 针对水资源刚性约束落地缺抓手的问题,按照以水定发展、协调定规模的理念,提出“四水四定”的分析思路和控制指标,厘清各类发展目标与水资源利用的协调关系。以公平为社会目标,以效益为经济目标,提出“尊重现状、保障刚需、效率驱动、区域均衡”的协调优化准则,建立目标函数和约束条件,构建“四水四定”多目标协调模型,以满足保障刚性需求基础上的水量高效流转,确定发展规模和水量分配方案。模型选取人均GDP最大实现效率驱动,使有限水量产生更大效益;选取区域人均GDP差异最小、发展匹配度最高实现发展公平,缩小区域经济差异;通过约束条件反映水资源约束、刚性需求保障、水源用户配置关系、经济社会发展合理范围等要求;设置罚函数协调约束条件不能满足时的目标值调整。通过归一化方法将多目标转化为单目标,基于现状设置初始条件,采用线性规划等方法求解,得出协调产业发展和水量优化分配的整体结果,通过结果评价反馈调整,形成可服务于经济社会发展和水资源管控决策的方案。 展开更多
关键词 水资源刚性约束 四水四定 水资源配置 多目标协调优化 用水效率 综合评价
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特金罕山国家自然保护区野生球根花卉资源综合评价 被引量:1
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作者 苏慧 张淑娟 +1 位作者 董永义 张丽娟 《中国野生植物资源》 CSCD 2024年第1期114-119,共6页
目的:为探究特金罕山国家自然保护区野生球根花卉资源,筛选出适合当地城市绿化的野生球根花卉种类。方法:采用野外实地调查和文献检索的方法,调查特金罕山国家自然保护区野生球根花卉资源,并运用层次分析法从观赏价值、适应性、开发价值... 目的:为探究特金罕山国家自然保护区野生球根花卉资源,筛选出适合当地城市绿化的野生球根花卉种类。方法:采用野外实地调查和文献检索的方法,调查特金罕山国家自然保护区野生球根花卉资源,并运用层次分析法从观赏价值、适应性、开发价值3个方面对其进行综合评价。结果:特金罕山国家自然保护区共有野生球根花卉37种,隶属12科,28属,其中,百合科种类最多,14种。根据综合评价结果,37种野生球根花卉分为4个等级:综合价值高的Ⅰ级(R>4.0)5种;综合价值较高的Ⅱ级(3.7<R≤4.0)10种;综合价值一般的Ⅲ级(3.5<R≤3.7)12种;综合价值较低的Ⅳ级(R≤3.5)10种。结论:特金罕山国家自然保护区野生球根花卉资源丰富,建议加强资源保护并优化开发利用方式,丰富城市园林绿化球根花卉种类。 展开更多
关键词 特金罕山国家自然保护区 野生球根花卉 层次分析法 综合评价
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高校大规模招生应用综合素质评价的困境与对策 被引量:1
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作者 靳培培 周倩 《黑龙江高教研究》 北大核心 2024年第2期32-39,共8页
综合素质评价纳入高校招生是新高考改革的重要内容,然而除了部分试点高校对综合评价招生进行积极探索以外,在高校大规模招生中尚未有效应用,影响到新高考改革的整体成效。从高校主体视角看,综合素质评价在高校大规模招生中的应用困境主... 综合素质评价纳入高校招生是新高考改革的重要内容,然而除了部分试点高校对综合评价招生进行积极探索以外,在高校大规模招生中尚未有效应用,影响到新高考改革的整体成效。从高校主体视角看,综合素质评价在高校大规模招生中的应用困境主要表现为“不能用”“不愿用”“不会用”“不敢用”的“四大困境”。实现高校在大规模招生中对综合素质评价“能用”“愿用”“会用”“敢用”,需要提升综合素质评价质量,扩大综合素质评价使用空间;树立正确的招生理念,控制招生录取工作成本;加强相关研究与探索,提升高校招生能力;加快构建社会诚信体系,提供包容的改革环境。 展开更多
关键词 综合素质评价 高校招生 大规模 新高考
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数字服务贸易国际竞争力比较研究 被引量:4
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作者 周升起 张皓羽 《重庆工商大学学报(社会科学版)》 2024年第1期90-100,共11页
随着科技发展水平的不断提高,数字技术越来越广泛地被运用到生产生活的各个领域。数字贸易作为新型贸易模式,引领着贸易发展的方向。通过考察数字技术方式交付的数字服务贸易,基于因子分析法构建数字服务贸易国际竞争力评价的综合评价指... 随着科技发展水平的不断提高,数字技术越来越广泛地被运用到生产生活的各个领域。数字贸易作为新型贸易模式,引领着贸易发展的方向。通过考察数字技术方式交付的数字服务贸易,基于因子分析法构建数字服务贸易国际竞争力评价的综合评价指标,利用2014—2018年OECD成员国和金砖国家为样本,比较分析40个样本国家综合因子得分和排名。结果显示:发达国家在数字服务贸易格局中竞争力较强,占据主导地位;发展中国家出口竞争力较弱,处于不利位置;中国数字服务贸易国际竞争力提升十分迅速,但在数字基础设施建设和政策支持环境等方面处于劣势,进而针对性地提出政策建议。 展开更多
关键词 数字服务贸易 国际竞争力 因子分析法 综合评价
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福建省山药种质资源品质比较与综合评价
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作者 张武君 刘保财 +2 位作者 陈菁瑛 黄颖桢 赵云青 《食品研究与开发》 CAS 2024年第9期75-85,共11页
该研究较为全面地收集福建省6个地市45份山药主栽种质资源,测定块茎的9个品质指标,利用隶属函数法、主成分分析和聚类分析对山药的营养品质、加工品质和综合品质进行评价。结果表明,测定的9个指标中,淀粉含量和可食率的变异系数低于8%,... 该研究较为全面地收集福建省6个地市45份山药主栽种质资源,测定块茎的9个品质指标,利用隶属函数法、主成分分析和聚类分析对山药的营养品质、加工品质和综合品质进行评价。结果表明,测定的9个指标中,淀粉含量和可食率的变异系数低于8%,其余7个指标的变异系数大于20%,其中块茎鲜重的变异系数高达59.90%。筛选出可溶性糖含量、淀粉含量、可溶性蛋白含量、尿囊素含量、折干率、可食率、块茎鲜重7项指标,构建营养品质和加工品质相结合的品质综合评价体系。聚类分析将福建山药种质资源聚为4类,第Ⅰ类营养和加工品质较一般;第Ⅱ类适合加工;第Ⅲ类适合鲜食;第Ⅳ类鲜食销售和加工均有优势。 展开更多
关键词 山药 资源 营养 加工 综合评价
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