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Employment Quality EvaluationModel Based on Hybrid Intelligent Algorithm
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作者 Xianhui Gu Xiaokan Wang Shuang Liang 《Computers, Materials & Continua》 SCIE EI 2023年第1期131-139,共9页
In order to solve the defect of large error in current employment quality evaluation,an employment quality evaluation model based on grey correlation degree method and fuzzy C-means(FCM)is proposed.Firstly,it analyzes... In order to solve the defect of large error in current employment quality evaluation,an employment quality evaluation model based on grey correlation degree method and fuzzy C-means(FCM)is proposed.Firstly,it analyzes the related research work of employment quality evaluation,establishes the employment quality evaluation index system,collects the index data,and normalizes the index data;Then,the weight value of employment quality evaluation index is determined by Grey relational analysis method,and some unimportant indexes are removed;Finally,the employment quality evaluation model is established by using fuzzy cluster analysis algorithm,and compared with other employment quality evaluation models.The test results show that the employment quality evaluation accuracy of the design model exceeds 93%,the employment quality evaluation error can meet the requirements of practical application,and the employment quality evaluation effect is much better than the comparison model.The comparison test verifies the superiority of the model. 展开更多
关键词 Employment quality fuzzy c-means clustering algorithm grey correlation analysis method evaluation model index system comparative test
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Evaluation and Driving Force Analysis of Cultivated Land Quality in Black Soil Region of Northeast China 被引量:1
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作者 WANG Mingchang LIU Xingnan +4 位作者 LIU Ziwei WANG Fengyan LI Xiaoyan HOU Guanglei ZHAO Shijun 《Chinese Geographical Science》 SCIE CSCD 2023年第4期601-615,共15页
Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this st... Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this study,320 counties in the black soil region of Northeast China(BSRNC)represent the research units used to construct the CQE system measuring the soil properties(SP),cultivated land productivity(CLP),ecological environment(EE)and social economy(SE).The total of 19 factors were selected to calculate the integrated fertility index(IFI)and divided into grades.Simultaneously,we used the coupling coordination degree model to comprehensively analyze the spatial pattern of the cultivated land quality(CLQ)in the BSRNC,and use the structural equation model(SEM)to analyze the driving mechanism.The results show the following:1)The CLQ of 262 counties in the BSRNC is in a state of coupling and coordination,and the coupling and coordination degree presents a spatial distribution pattern of‘high in the southwest and northeast,low in the northwest and southeast’.The coordinated development degree of 271 counties is between 0.4 and 0.6,which is in a transitional state between coordination and disorder.2)The CLQ in the BSRNC is generally good,with an average grade of 3.High-quality cultivated land accounts for 58.45%of all counties,middle-and upper-quality cultivated land accounts for 27.05%,and poor-quality cultivated land accounts for 14.49%.3)The SEM analysis shows that the SP,CLP,EE,and SE all influence the CLQ.Among them,the SP has the largest driving force on the CLQ,while the SE has the smallest driving force on it.The results confirm that the main factors affecting the evaluation results are crop productivity level,normalized difference vegetation index,ratio vegetation index,difference vegetation index,and organic carbon content.When implementing protection measures in counties with a low CLQ,considering a balanced coordination of multiple systems and reasonably controlling the quality degradation are important.This study provides the current situation and driving factors of the CLQ in the BSRNC and will play an important role in black soil governance and utilization. 展开更多
关键词 cultivated land quality evaluation(CQE) black soil region of Northeast China(BSRNC) coupling coordination degree model structural equation model(SEM) driving forces
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Application of Projection Pursuit Evaluation Model Based on Real-Coded Accelerating Genetic Algorithm in Evaluating Wetland Soil Quality Variations in the Sanjiang Plain, China 被引量:34
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作者 FUQIANG XIEYONGGANG WEIZIMIN 《Pedosphere》 SCIE CAS CSCD 2003年第3期249-256,共8页
A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded ... A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded accelerating genetic algorithm (RAGA), the projection direction is optimized and multi-dimensional indexes are converted into low-dimensional space. Classification of wetland soils and evaluationof wetland soil quality variations are realized by pursuing optimum projection direction and projection func-tion value. Therefore, by adopting this new method, any possible human interference can be avoided andsound results can be achieved in researching quality changes and classification of wetland soils. 展开更多
关键词 evaluation projection pursuit evaluation model real-coded acceleratinggenetic algorithm soil quality variations
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High-resolution modeling and evaluation of ozone air quality of Osaka using MM5-CMAQ system 被引量:7
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作者 SHRESTHA Kundan Lal KONDO Akira +1 位作者 KAGA Akikazu INOUE Yoshio 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第6期782-789,共8页
High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with com... High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with complex terrain and land-use. This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka, Japan. The 1-km and 3-kin grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region. High-resolution Grid Point Value-Mesoscale Model (GPV-MSM) data were used after suitable validation. The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone. Daily maxima of ozone were found better simulated by the 1-krn grid domain than the coarser 9-km and 3-km domains, with the maximum improvement in the mean absolute gross error about 3 ppbv. In addition, 1-km grid results fared better than other grids at most of the observation stations that showed noticeable differences in gross error as well as correlation. These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region, such as the Osaka region, which has complex terrain and land-use. 展开更多
关键词 air quality model evaluation OZONE Community Multiscale Air quality MM5 statistical analysis
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Three-Dimensional Tidal Model and Its Application to Numerical Simulation of Water Quality in Coastal Waters 被引量:5
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作者 Shen Yongming , Li Yucheng and Zhao Wenqian Associate Professor, Department of Civil Engineering, Dalian University of Technology, Dalian 116023 Professor, Department of Civil Engineering, Dalian University of Technology, Dalian 116023 Professor, Department of Civil Engineering, Sichuan Union University, Chengdu 610065 《China Ocean Engineering》 SCIE EI 1994年第4期425-436,共12页
The turbulence mechanism plays an important part in the mixing process and momentum transfer of turbulence. A three-dimensional Prandtl mixing length tidal model has been developed to simulate tidal flows and water qu... The turbulence mechanism plays an important part in the mixing process and momentum transfer of turbulence. A three-dimensional Prandtl mixing length tidal model has been developed to simulate tidal flows and water quality. The eddy viscosities and diffusivities are computed from the Prandtl mixing length model. In order to model the water quality of an estuary or coastal area many interdependent processes need to be simulated. These may be conveniently separated into three main groups: transport and mixing processes, biochemical interaction of water quality variables and the utilization and re-cycling of nutrients by living matter. The model simulates full oxygen and nutrient balance, primary productivity and the transport, reaction mechanism and fate of pollutants over tidal time-scales. The model is applied to numerical simulation of tidal flows and water quality in Dalian Bay. The model has been calibrated against a limited data set of historical water quality observations and in general demonstrates excellent agreement with all available data. 展开更多
关键词 three-dimension tidal flows water quality ECOSYSTEM mixing length model coastal waters
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Water Quality Evaluation in Tidal River Reaches of Liaohe River Estuary, China Using a Revised QUAL2K Model 被引量:7
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作者 YE Hanfeng GUO Shuhai +1 位作者 LI Fengmei LI Gang 《Chinese Geographical Science》 SCIE CSCD 2013年第3期301-311,共11页
Rivers in the Liaohe River Estuary area have been seriously polluted by discharges of wastewater containing petroleum pol- lutants and nutrients. In this paper, The Enhanced Stream Water Quality Model (QUAL2K) and i... Rivers in the Liaohe River Estuary area have been seriously polluted by discharges of wastewater containing petroleum pol- lutants and nutrients. In this paper, The Enhanced Stream Water Quality Model (QUAL2K) and its revised model as well as One-dimensional Tide Mean Model (1D model) were applied to predict and assess the water quality of the tidal fiver reach of the Liaohe River Estuary. Dissolved oxygen (DO), biochemical oxygen demand (BODs), ammonia nitrogen (NH3-N) and total phosphorus (TP) were chosen as water quality indices in the two model simulations. The modelled results show that the major reasons for degraded rivers remain petroleum and non-point source pollution. Tidal water also has a critical effect on the variation of water quality. The sensitivity analysis identifies that flow rate, point load and diffuse load are the most sensitive parameters for the four water quality indices in the revised QUAL2K simulation. Uncertainty analysis based on a Monte Carlo simulation gives the probability distribution of the four wa- ter quality indices at two locations (6.50 km and 44.84 km from the river mouth). The statistical outcomes indicate that the observed data fall within the 90% confidence intervals at all sites measured, and show that the revised QUAL2K gives better results in simulating the water quality of a tidal fiver. 展开更多
关键词 tidal river reach water quality evaluation revised QUAL2K model uncertainty analysis Liaohe River Estuary
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Quality Evaluation Model for Map Labeling 被引量:2
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作者 FANHong ZHANGZuxun DUDaosheng 《Geo-Spatial Information Science》 2005年第1期72-78,共7页
This paper discusses and sums up the basic criterions of guaranteeing the labeling quality and abstracts the four basic factors including the conflict for a label with a label, overlay for label with the features, pos... This paper discusses and sums up the basic criterions of guaranteeing the labeling quality and abstracts the four basic factors including the conflict for a label with a label, overlay for label with the features, position’s priority and the association for a label with its feature. By establishing the scoring system, a formalized four-factors quality evaluation model is constructed. Last, this paper introduces the experimental result of the quality evaluation model applied to the automatic map labeling system-MapLabel. 展开更多
关键词 map labeling quality evaluation model
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A Sound Quality Objective Evaluation Method Based on Auditory Peripheral Simulation Model 被引量:1
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作者 Yinhan Gao~1,Jun Xie~2,Jie Liang~1,Xin Chang~3,Baojun Wu~2 1.Experimental Centre of Testing Science,Jilin University,Changchun 130022,P.R.China 2.College of Instrumentation & Electrical Engineering,Jilin University,Changchun 130061,P.R.China 3.Laboratory of Applications and Computations in Electromagnetics and Optics,Department of Electrical Engineering, University of Washington,WA 98195-2500,USA 《Journal of Bionic Engineering》 SCIE EI CSCD 2010年第2期199-208,共10页
Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on ... Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on sound wave trans-mission.This method employs the artificial head technique, in which the head related transfer function was taken into account tothe outer ear simulation phase.First, a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical explanations.Then the auditory peripheral simulation model was built, which mimicsthe physiological functions of the human hearing, simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory system.Finally, performance comparison was made between the proposed SQOEmethod and ArtemiS software, and the verifications of subjective and objective related analysis were made.Results show thatthe proposed method was economical, simple, and with good evaluation quality. 展开更多
关键词 sound quality objective evaluation auditory peripheral simulation model artificial head head related transfer function
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Perceptual Quality Assessment of Omnidirectional Images:Subjective Experiment and Objective Model Evaluation 被引量:1
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作者 DUAN Huiyu ZHAI Guangtao +3 位作者 MIN Xiongkuo ZHU Yucheng FANG Yi YANG Xiaokang 《ZTE Communications》 2019年第1期38-47,共10页
Virtual reality(VR) environment can provide immersive experience to viewers.Under the VR environment, providing a good quality of experience is extremely important.Therefore, in this paper, we present an image quality... Virtual reality(VR) environment can provide immersive experience to viewers.Under the VR environment, providing a good quality of experience is extremely important.Therefore, in this paper, we present an image quality assessment(IQA) study on omnidirectional images. We first build an omnidirectional IQA(OIQA) database, including 16 source images with their corresponding 320 distorted images. We add four commonly encountered distortions. These distortions are JPEG compression, JPEG2000 compression, Gaussian blur, and Gaussian noise. Then we conduct a subjective quality evaluation study in the VR environment based on the OIQA database. Considering that visual attention is more important in VR environment, head and eye movement data are also tracked and collected during the quality rating experiments. The 16 raw and their corresponding distorted images,subjective quality assessment scores, and the head-orientation data and eye-gaze data together constitute the OIQA database. Based on the OIQA database, we test some state-of-the-art full-reference IQA(FR-IQA) measures on equirectangular format or cubic formatomnidirectional images. The results show that applying FR-IQA metrics on cubic format omnidirectional images could improve their performance. The performance of some FR-IQA metrics combining the saliency weight of three different types are also tested based on our database. Some new phenomena different from traditional IQA are observed. 展开更多
关键词 perceptual quality assessment OMNIDIRECTIONAL IMAGES SUBJECTIVE EXPERIMENT objective model evaluation VISUAL SALIENCY
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Advances in Application of Models in Soil Quality Evaluation 被引量:1
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作者 SI Zhi-guo WANG Ji-jie +3 位作者 YU Yuan-chun LIANG Guan-feng CHEN Chang-ren SHU Hong-lan 《Asian Agricultural Research》 2012年第11期89-93,共5页
Soil quality is a comprehensive reflection of soil properties.Since the soil quality concept was put forward in the 1970s,the quality of different type soils in different regions have been evaluated through a variety ... Soil quality is a comprehensive reflection of soil properties.Since the soil quality concept was put forward in the 1970s,the quality of different type soils in different regions have been evaluated through a variety of evaluation methods,but it still lacks universal soil quantity evaluation models and methods.In this paper,the applications and prospects of grey relevancy comprehensive evaluation model,attribute hierarchical model,fuzzy comprehensive evaluation model,matter-element model,RAGA-based PPC /PPE model and GIS model in soil quality evaluation are reviewed. 展开更多
关键词 SOIL quality evaluation model APPLICATION
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Comprehensive Evaluation of Water Quality of Rivers in Binzhou Based on RAGA-PPCE Model 被引量:1
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作者 Li Xin Guo Ning 《Meteorological and Environmental Research》 CAS 2018年第6期62-65,共4页
The water quality of main rivers in Binzhou City,Shandong Province was comprehensively evaluated based on RAGA-PPCE model. Six main factors such as ammonia nitrogen(NH-N),total phosphorus(TP),total nitrogen(TN),chemic... The water quality of main rivers in Binzhou City,Shandong Province was comprehensively evaluated based on RAGA-PPCE model. Six main factors such as ammonia nitrogen(NH-N),total phosphorus(TP),total nitrogen(TN),chemical oxygen demand(COD),dissolved oxygen(DO) and p H were used to establish the evaluation and classification standards of water quality. The results show that the evaluation results of water quality by RAGA-PPCE model and the fuzzy comprehensive evaluation method are basically the same. The evaluation results of RAGA-PPCE model are objective and reasonable and can be applied to the comprehensive evaluation of water quality. 展开更多
关键词 RAGA-PPCE model evaluation of water quality Projection pursuit Binzhou City
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SERVQUAL Model Based Evaluation Analysis of Railway Passenger Transport Service Quality in China 被引量:1
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作者 Huiwei Niu Jiao Yao +1 位作者 Jing Zhao Jin Wang 《Journal on Big Data》 2019年第1期17-24,共8页
Railway is the backbone of Chinese transportation system,but its poor quality of services for passengers cause complains now and then.This study first analyzed the influencing factors of service quality on railway pas... Railway is the backbone of Chinese transportation system,but its poor quality of services for passengers cause complains now and then.This study first analyzed the influencing factors of service quality on railway passenger,and its quality characteristics was also explained,and finally we proposed an evaluation system of service quality on railway passenger transport.Through the statistical analysis and processing of the basic information from survey data from railway station,trains and the official website of the ticket purchase,the evaluation score of question naire was converted into the score in evaluation index system,which was based on SERVQUAL model.Finally,the evaluation index system was applied to the field test,and all levels of indicators and the overall evaluation of railway passenger transport service quality was obtained.The relevant results show that the evaluation model of this study is concise and practical,and the method has certain practicability and promotion value,which is beneficial to the department of management supervision in railway transportation. 展开更多
关键词 RAILWAY PASSENGER TRANSPORT service quality evaluation INDEX SERVQUAL model PASSENGER SATISFACTION
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Complex Sequence Quality Evaluation Model for Concealed Water Supply Pipeline of Prefabricated Construction
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作者 HAN Shasha CHEN Qun +1 位作者 LI Jie DAI Yijing 《Journal of Donghua University(English Edition)》 EI CAS 2019年第2期179-186,共8页
The accurate assessment of the quality can materially affect the safety and life of the prefabricated construction.In this paper,we studied the overall module of concealed water supply pipeline,and a new complex seque... The accurate assessment of the quality can materially affect the safety and life of the prefabricated construction.In this paper,we studied the overall module of concealed water supply pipeline,and a new complex sequence quality evaluation model was established.By analyzing the small evaluation index elements of the model,the weight of the larger evaluation index could be deduced.The total quality evaluation score of the overall module could be obtained by calculating the weight value of the evaluation index,and then the quality standard of the overall module could be obtained. 展开更多
关键词 PREFABRICATED construction concealed water supplypipeline overall MODULE COMPLEX SEQUENCE quality evaluation model quality evaluation system
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Applying PP Model Based on RAGA in Water Environment Quality Evaluation
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作者 PANFeng FUQiang +1 位作者 LIANGChuan LIUDong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第2期171-175,共5页
Projection Pursuit (PP) model is a technique of falling high dimension. Real coding based on Accelerating Genetic Algorithm (RAGA) is a method of optimum. Through combining the PP model and RAGA, the paper applies the... Projection Pursuit (PP) model is a technique of falling high dimension. Real coding based on Accelerating Genetic Algorithm (RAGA) is a method of optimum. Through combining the PP model and RAGA, the paper applies the model in the water environment quality evaluation. The writer takes the water quality evaluated indexes of each sample as projection direction and turns high dimension data into low dimension projection value. Thus, the writer achieves on evaluating the grade of water samples and its optimum order. Based on this, the writer overcomes the jamming of weights calculated on fuzzy synthesize judge and gray system valuation. The paper can provide a new thought for water environment quality evaluation and other falling high dimension and optimum issue. 展开更多
关键词 RAGA PP model water environment quality evaluation
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Performance evaluation of quality monitor models in spot welding
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作者 张忠典 李冬青 王凯 《China Welding》 EI CAS 2005年第1期58-62,共5页
Performance of quality monitor models in spot welding determines the monitor precision directly, so it’s crucial to evaluate it. Previously, mean square error (MSE) is often used to evaluate performances of models, b... Performance of quality monitor models in spot welding determines the monitor precision directly, so it’s crucial to evaluate it. Previously, mean square error (MSE) is often used to evaluate performances of models, but it can only show the total errors of finite specimens of models, and cannot show whether the quality information inferred from models are accurate and reliable enough or not. For this reason, by means of measure error theory, a new way to evaluate the performances of models according to the error distributions is developed as follows: Only if correct and precise enough the error distribution of model is, the quality information inferred from model is accurate and reliable. 展开更多
关键词 spot welding quality monitor model performance evaluation
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Evaluation of Nutrient Components and Nutritive Quality of Larimichthys crocea(Big Yellow Croaker)in Different Aquaculture Models
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作者 Zhong Aihua Chu Zhangjie +1 位作者 Dai Luyi Wang Xiaojun 《Animal Husbandry and Feed Science》 CAS 2014年第6期296-299,318,共5页
To ascertain the nutrient components and nutritive quality of the flesh of big yellow croaker in three culture conditions ( traditional cage, offshore cage and cage-free), basic nutritional components,amino acid,fat... To ascertain the nutrient components and nutritive quality of the flesh of big yellow croaker in three culture conditions ( traditional cage, offshore cage and cage-free), basic nutritional components,amino acid,fatty acid and mineral elements were determined. The results indicated that crude protein in flesh of the big yellow croaker in cage-free culture was higher than that in offshore cage and much higher than that in traditional cage ( P 〈0.05). Crude fat of the croaker cul- tured in the traditional cage was twice as high as that in cage-free culture, while that in the offshore cage was in the middle. Proline content in the cage-free culture was much higher than that in the offshore cage, and also than that in the traditional cage (P 〈 0.05 ). There was no significant difference in the content of alanine, methionine and tryptophan ( P 〈 0.05). Contents of other amino acids had no significant difference between the cage-free culture and offshore cage, but were much lower in the traditional cage (P 〈 0.05 ). Top six fatty acids were 9-Hexadecenoic acid, palmitic acid,9-Octadecenoic acid, Octadecauoic acid, DHA and EPA. The palmitic acid content was the highest in cage-free culture and in traditional cage, 9-Octadeeenoic acid content was the highest in offshore cage. Content of unsaturat- ed fatty acids in cage-free culture, offshore cage and traditional cage was 63.60,66.32,57.67, respectively, and polyunsaturated fatty acid was 29.10, 28.57, and 24.40. Content of DHA in cage-free culture was significantly higher than that in the offshore and traditional cage. Content of zinc had no significant difference in three culture models. Content of phosphorus had no significant difference between that in cage-free culture and offshore cage, was lower in the traditional cage. The cage-free cultured croakers had the highest content of calcium and phosphorus. Content of selenium was about the same between the offshore cage and the traditional cage stocking, higher in the cage-free culture. This research has considerable application value for identifying quality and sources of the big yellow croakers. 展开更多
关键词 Culture model Larimichthys crocea (big yellow croaker) Fish nutrient quality evaluation
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Study on quality evaluation model in multi-station assembly processes
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作者 Wen Zejun Liu Deshun Yang Shuyi 《Engineering Sciences》 EI 2008年第4期25-30,共6页
Based on features of dimension variation propagation in multi-station assembly processes,a new quality evaluation model of assembly processes is established. Firstly,the error source of multi-station assembly system i... Based on features of dimension variation propagation in multi-station assembly processes,a new quality evaluation model of assembly processes is established. Firstly,the error source of multi-station assembly system is analyzed,the relationship of dimension variation propagation in multi-station assembly processes is studied and the state equation for variation propagation is constructed too. Then,the feature parameters which influence variation propagation and accumulation in multi-station assembly processes are found to evaluate quality characteristic of the assembly system. Through the derivation of equation on dimension variation propagation,station coefficient matrices which are combined and conversed to determine the max eigenvalue are educed. The max eigenvalue is multiplied by the weight coefficient to establish the quality evaluation model in multi-station assembly processes. Furthermore,assembly variation indexes are proposed to judge of the assembly technology process. Finally,through the practical example,the application of the model and assembly variation indexes are presented. 展开更多
关键词 MULTI-STATION quality evaluation model variation propagation assembly variation indexes
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Study on Evaluation Method of Teaching Quality Based on Cloud Model and D-S Theory
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作者 Jianting Shi Jun Sun +2 位作者 Jiancai Wang Jingping Cao Chunyuan Liu 《国际计算机前沿大会会议论文集》 2019年第2期300-302,共3页
The Evaluation of teaching quality is a complicated project. It’s a typical problem of uncertainty. A design scheme of teaching quality evaluation method based on cloud model and D-S theory is proposed with the schoo... The Evaluation of teaching quality is a complicated project. It’s a typical problem of uncertainty. A design scheme of teaching quality evaluation method based on cloud model and D-S theory is proposed with the school teaching evaluation index. With the experiences and knowledge of experts, evaluation index was described by cloud model and judgment matrix of AHP was revised by D-S theory. The weight of evaluation indexes was determined reasonably and objectively. Applied in the actual environment, the method can make an accurate and efficient evaluation with a certain practical value. 展开更多
关键词 TEACHING quality evaluation CLOUD model D-S THEORY
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Modeling and performance evaluation of QoS-aware job scheduling of computational grids
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作者 单志广 林闯 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期425-430,共6页
To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated ... To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated QoS-aware job dispatching policy is proposed, which correlates priorities of incoming jobs used for job selecting at the local scheduler of the grid node with the job dispatching policies at the global scheduler for computational grids. The stochastic high-level Petri net (SHLPN) model of a two-level hierarchy computational grid architecture is presented, and a model refinement is made to reduce the complexity of the model solution. A performance analysis technique based on the SHLPN is proposed to investigate the QoS-aware job scheduling policy. Numerical results show that the QoS-aware job dispatching policy outperforms the QoS-unaware job dispatching policy in balancing the high-priority jobs, and thus enables priority-based QoS. 展开更多
关键词 computational grids job scheduling quality of service (QoS) performance evaluation modelING stochastic high-level Petri net (SHLPN)
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Evaluation, prediction, and protection of water quality in Danjiangkou Reservoir, China 被引量:15
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作者 Xiao-kang Xin Ke-feng Li +1 位作者 Brian Finlayson Wei Yin 《Water Science and Engineering》 EI CAS CSCD 2015年第1期30-39,共10页
The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SN... The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SNWDP), which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus (TP), permanganate index (CODM,), dissolved oxygen (DO), and five-day biochemical oxygen demand (BODs), and the concentrations of TP, BODs, ammonia nitrogen (NH3--N), CODM,, DO, and anionic surfactant (Surfa) do not reach the specified standard levels in the tributaries. Seasonal Mann--Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis (CA) results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation. 展开更多
关键词 Water quality Single factor evaluation method Mann--Kendall test Numerical modeling Cluster analysis Dangjiangkou Reservoir
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