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Entropy method for determination of weight of evaluating indicators in fuzzy synthetic evaluation for water quality assessment 被引量:217
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作者 ZOU Zhi-hong YUN Yi SUN Jing-nan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期1020-1023,共4页
Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method w... Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method was introduced. This improved method for determination of weight of the evaluating indicators was applied in water quality assessment of the Three Gorges reservoir area. The results showed that this method was favorable for fuzzy synthetic evaluation when there were more than one evaluating objects. One calculation was enough for calculating every monitoring point. Compared with the original evaluation method, the method predigested the fuzzy synthetic evaluation process greatly and the evaluation results are more reasonable. 展开更多
关键词 water quality evaluation FUZZY weight of evaluating indicator entropy method
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Determination of Content of Amino Acid in Abalone by Precolumn Derivatization and its Nutritional Value Evaluation 被引量:5
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作者 Wen CHEN Xiangjun WANG +3 位作者 Yujie WANG Yuzhi HUANG Fanmeng MENG Hui CHEN 《Agricultural Biotechnology》 CAS 2018年第3期178-183,210,共7页
[Objectives] This study was conducted to optimize the determination conditions of amino acids from abalone. [Methods] The sample was treated by acid hydrolysis method and subjected to 2,4-2 nitro fluorobenzene column ... [Objectives] This study was conducted to optimize the determination conditions of amino acids from abalone. [Methods] The sample was treated by acid hydrolysis method and subjected to 2,4-2 nitro fluorobenzene column derivatization. The amino acid content in abalone was determined by HLPC,and the nutritional value of the amino acids was evaluated with egg protein model put forward by Institute of Nutrition and Food Hygiene,Chinese Academy of Preventive Medicine. [Results] Abalone contains full amino acids. According to the FAO/WHO ideal,it is a high-quality protein source and suitable for supplement of protein source for human body. [Conclusions]The experimental method has simple operation and could achieve a good effect with wide linear range and correlation coefficient over 0. 999 8,and the obtained results are satisfactory. 展开更多
关键词 ABALONE Precolunm derivatization HPLC Amino acid evaluation
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Satellite Positioning and Orbit Determination System(SPODS):Introduction and Evaluation 被引量:7
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作者 Ziqing WEI Rengui RUAN +5 位作者 Xiaolin JIA Xianbing WU Xiaoyong SONG Yue MAO Laiping FENG Yongxing ZHU 《Journal of Geodesy and Geoinformation Science》 2018年第1期25-29,共5页
The Satellite Positioning and Orbit Determination System(SPODS)is a software package for GNSS positioning/orbit determination,developed by the Xi’an Research Institute of Surveying and Mapping.So far it has been able... The Satellite Positioning and Orbit Determination System(SPODS)is a software package for GNSS positioning/orbit determination,developed by the Xi’an Research Institute of Surveying and Mapping.So far it has been able to analyse GPS data and has the capability of high precision GPS positioning and orbit determination.The underlying theory and the performance evaluation are briefly addressed in this paper.The experiments are carried out with GPS data collected from about 127 IGS stations during 4~10 January 2009.The results show that the RMS 1D difference is 1.1 cm between SPODS orbits and final IGS combined orbits,and that the repeatability of daily solutions of station coordinates is 1.5 mm for horizontal components,and 4.5 mm for vertical component,and that the consistency of ERP solutions with IGS final products is 0.025 mas,0.093 mas and 0.013 ms/d respectively for pole coordinates and LOD. 展开更多
关键词 GNSS PRECISE POSITIONING PRECISE ORBIT determination ERP determination SPODS
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Evaluation of Some Secondary Metabolites and Determination of the Antioxidant Potential of Different Extracts from the Plant of <i>Pteridium aquilinum</i> 被引量:2
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作者 Arnaud W. G. Tamba Sompila Aimé B. Madiélé Mabika +5 位作者 Nadia P. G. Pambou-Tobi Tsiba Gouollaly Jacques E. Moussounga Gloria L. L. Bissombolo N’simba Roniche Nguie Louis Matos 《American Journal of Analytical Chemistry》 2021年第12期506-519,共14页
The present study aims to make an evaluation of some secondary metabolites and determination of the antioxidant potential of <i>P. aquilinum</i> plant extracts obtained by means of a simple and rapid TLC m... The present study aims to make an evaluation of some secondary metabolites and determination of the antioxidant potential of <i>P. aquilinum</i> plant extracts obtained by means of a simple and rapid TLC method. The latter revealed the presence of terpenes, sterols, steroids, flavonoids, polyphenols, saponins, sugars and amino acids. The evaluation of the potential antioxidant was assessed on phenolic and flavonoid compounds. These compounds’ dosages revealed different levels, but the highest antioxidant activity was found in the hydro-ethanol extract followed by the aqueous extract. Among the two families of evaluated antioxidants, phenolic compounds were found to be higher in the hydro-ethanolic extract (75.18 mgEAG/gM<sub>S</sub>), followed by the aqueous extract (66.78 mgEAG/gM<sub>S</sub>) and lower in the ethanolic extract (12.39 mgEAG/gM<sub>S</sub>). Whereas flavonoids, less significantly elevated, showed values of 2.58 mgECa/gM<sub>S</sub> for the hydro-ethanolic extract, 2.24 mgECa/gM<sub>S</sub> for the aqueous extract and 1.58 mgECa/gM<sub>S</sub> for the ethanolic extract. However, the antiradical activity was also evaluated. Contrary to the antioxidant activity, the most important antiradical activity was observed on the hydroethanolic extract with a rate of 3.61 mg/mL, then a weak activity on the aqueous and ethanolic extracts respectively 6.18 mg/mL and 15.81 mg/mL, then less important on the aqueous and hydro-ethanolic extracts respectively at levels of 6.18 mg/mL and 3.61 mg/mL. 展开更多
关键词 evaluation EXTRACTS Secondary Metabolites Potential Antioxidant Pteridium aquilinum
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Evaluation of Microwave Plasma Torch (MPT) as an Excitation Source for Determination of Mercury
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作者 Duan Yixiang, Du Xiaoguang and Jin Qinhan (Department of Chemistry, Jilin University, Changchun) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第1期31-32,共2页
The microwave plasma atomic spectrometry is an important branch of the plasma atomic spectrometry. Since the first use of microwave induced plasma(MIP) as an excitation source for spectral Chemical analysis by Broid... The microwave plasma atomic spectrometry is an important branch of the plasma atomic spectrometry. Since the first use of microwave induced plasma(MIP) as an excitation source for spectral Chemical analysis by Broida and Chapmanin in 1958, especially the introduction of TM;cavity by Beenakker in 1976 and of surfatron by Moisan in 1979 with which an atmospheric pressure helium MIP could be obtained, MIP has received considerable attention as a new excitation source for spectrometric analysis. However, since MIP suffers from the in ability to analyse the aqueous sam- 展开更多
关键词 Microwave plasma torch Atomic spectrometry Mercury determination
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Evaluation of Atomic Fluorescence Spectrometry for Determination of Mercury Using a Low-Powered Argon Microwave Plasma Torch (MPT)
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作者 Duan Yixiang, Kong Xiangxing, Zhang Hanqi, Liu Jun Jin Qinhan (Department of Chemistry, Jilin University, Changchun) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1991年第1期59-61,共3页
The Microwave-Induced Plasma (MIP) has received considerable attention during the past decade since theintroduction of the Becnakker Cavity. It has been commonly used as an atomization cell for atomic emission spectro... The Microwave-Induced Plasma (MIP) has received considerable attention during the past decade since theintroduction of the Becnakker Cavity. It has been commonly used as an atomization cell for atomic emission spectrometry (AES) and atomic absorption spectrometry (AAS), and a great success was achieved for both techniques. More 展开更多
关键词 Atomic fluorescence spectrometry Argon microwave torch determination of mercury
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Evaluation of a handheld creatinine measurement device for real-time determination of serum creatinine in radiology departments
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作者 Stefan Haneder Alexandra Gutfleisch +5 位作者 Claudia Meier Joachim Brade Dieter Hannak Stefan O Schoenberg Christoph R Becker Henrik J Michaely 《World Journal of Radiology》 CAS 2012年第7期328-334,共7页
AIM: To assess the feasibility/accuracy of a commercial handheld device in the context of increased demand for point-of-care serum creatinine (SCr) determination. METHODS: In this institutional review board-approved, ... AIM: To assess the feasibility/accuracy of a commercial handheld device in the context of increased demand for point-of-care serum creatinine (SCr) determination. METHODS: In this institutional review board-approved, prospective study, 401 patients referred for contrastenhanced computed tomography were included at two centres. Capillary (c)SCr was determined using two devices A+B and venous (v)SCr was determined in the centre's laboratory. Method comparison statistics for both centres and for vSCr<>1.2 mg/dL, receiver operating characteristic analysis, negative predictive values (NPV), sensitivity and specificity were calculated pre-/ post-curve offset correction with vSCr. RESULTS: Pearson's coefficients for cSCr vs vSCr were: centre 1-A:0.93/B:0.92; centre 2-A:0.85/B:0.82 (all P < 0.0001). Overall correlation was better for vSCr > 1.2 mg/dL. The area under the receiver operating characteristic curves showed a high accuracy for cSCr, but the device underestimated SCr, which was confirmed by Bland-Altman plot. Addition of the offset correction factor to the original data from centre 1 resulted in an improvement in sensitivity for detecting patients at risk (> 1.2 mg/dL), whilst maintaining acceptable specificity and improving NPV. CONCLUSION: This study showed the feasibility of SCr determination using the evaluated handheld device in a routine clinical setting. The device showed high sensitivity and high NPV, but may significantly underestimate SCr without offset correction to local laboratories. 展开更多
关键词 Contrast-medium-induced NEPHROPATHY Nephrogenic SYSTEMIC FIBROSIS Point of care testing Serum CREATININE determination StatSensor
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Quality Evaluation of Yi Medicine "Qibujing" Based on Determination of Water Content and Ash Content
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作者 Xuexue LI Hongna SU +5 位作者 Ying LI Xiaoxia CAI Risha WEIZE Zhengming YANG Yingfen HAO Yuan LIU 《Medicinal Plant》 CAS 2020年第1期67-68,92,共3页
[Objectives]To determine the water content,total ash content and acid-insoluble ash content of Yi medicinal material"Qibujing",so as to provide experimental basis for establishing the Quality Standard(Draft)... [Objectives]To determine the water content,total ash content and acid-insoluble ash content of Yi medicinal material"Qibujing",so as to provide experimental basis for establishing the Quality Standard(Draft)of Yi Medicinal Material"Qibujing"in Sichuan Province.[Methods]According to the second method(drying method)in 0832 water content determination method and 2301 ash content determination method in Chinese Pharmacopoeia(2015 Edition),it was determined,respectively,and the data were processed by IBM SPSS Statistics 26 and DPS 7.05 data processing system.[Results]All the 14 batches of sample met the stipulation that the water content should not exceed 12.0%,the total ash content should not exceed 8.0%,and the acid-insoluble ash content should not exceed 1.5%under"Guan Zhong-(Qibujing)"in the 2005 edition of Yunnan Traditional Chinese Medicine Standard.There was a negative correlation between water content,acid-insoluble ash content and altitude,and a positive correlation between total ash content and altitude.[Conclusions]It is suggested that Quality Standard(Draft)of Yi Medicinal Material"Qibujing"in Sichuan Province stipulate that the water content should not exceed 12.0%,the total ash content should not exceed 8.0%,and the acid-insoluble ash content should not exceed 1.5%. 展开更多
关键词 YI medicine"Qibujing" POTENTILLA fulgens WATER CONTENT ASH CONTENT CONTENT determination
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Simultaneous Determination of Bufadienolides and Qualitative Evaluation for Venenum Bufonis by High Performance Liquid Chromatography
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作者 HUANG Hao LIANG Ming-jin +1 位作者 LUO Heng ZHANG Wei-dong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第6期801-806,共6页
A high performance liquid chromatographic method was used for the simultaneous identification and qualitative evaluation of 12 bufadienolides(resibufogenin, einobufagin, cinobufaginol, arenobufagin, bufalin, bufotali... A high performance liquid chromatographic method was used for the simultaneous identification and qualitative evaluation of 12 bufadienolides(resibufogenin, einobufagin, cinobufaginol, arenobufagin, bufalin, bufotalin, gamabufotalin, cinobufotalin, ψ-bufaranogin, desacetylcinobufagin, telocinobufagin and resibufogenol) in Venenum Bufonis. The chromatographic separation was performed on a Dikma C18 analytical column via gradient elution with an aqueous solution of acetonitrile and 0.3% acetic acid at a flow rate of 0.8 mL/min. The method was validated to be acceptable in consideration of linearity(r2 〉 0.9992) and recovery(ranged from 98.9% to 102.0%). The limits of detection of the bufadienolides were from 0.48 ng for bufalin to 6.00 ng for cinobufotalin. The intra-day and inter-day precisions of the method were evaluated and were less than 3.0%. The method was successfully used to analyze 19 batches of Venenum Bufonis, and the similarity values between batches were calculated by Similarity Evaluation System for Chromatographic Fingerprint of TCM(Version 2004A, Chinese Pharmacopoeia Committee, Beijing). The results show that the contents of bufadienolides in the medicine and the similarity values based on these bufadienolides varied significantly from batch to batch. This proposed method could be utilized to qualify and control Venenum Bufonis to ensure its safety and efficacy in application. 展开更多
关键词 BUFADIENOLIDE High performance liquid chromatography Simultaneous analysis Qualitative evaluation Venenum Bufonis
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Determination and Evaluation of Heavy Metal Content of Freshwater Economic Fish in Northeast Guangdong
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作者 Yanmei ZHONG Qingmei ZHENG +2 位作者 Chunyan HAN Rushu WEN Hongli ZHANG 《Asian Agricultural Research》 2015年第1期61-65 70,70,共6页
Concentrations of lead( Pb),cadmium( Cd),chromium( Cr),copper( Cu),zinc( Zn) and manganese( Mn) were measured in various organs( such as in liver and muscle) from 9 species of freshwater economic fishes which were col... Concentrations of lead( Pb),cadmium( Cd),chromium( Cr),copper( Cu),zinc( Zn) and manganese( Mn) were measured in various organs( such as in liver and muscle) from 9 species of freshwater economic fishes which were collected from northeast area of Guangdong Province. The concentration of metals was measured by inductively coupled plasma atomic emission spectrometry( ICP- AES). Results showed that the levels of metals in hepatopancreas of the fishes were found in order of Zn > Pb > Cu > Hg > Cd,while in muscles were Zn > Cr> Pb > Mn > Cu > Cd. In general,the metals concentrations were significantly higher in liver samples than that in muscle samples. Based on the " pollution index of single factor",the fishes,to one degree or another,were polluted by Pb,Cd,Cr,Cu and Zn,and pollution levels were mostly followed by Pb > Cd > Cr > Cu > Zn. The indexes of Pb and Cd tested in hepatopancreas of the fishes were in a majority exceeded the national safety criteria for food in China. What's more,it was found that the contents of the heavy metals in fishes did not vary with the trophic level which they belong to. In summary,the fishes were polluted by Pb,Cd,Cr,Cu and Zn to some extent,which indicated that hidden danger of heavy metals pollution was present in ecological environment or safety in fishery production in the area. 展开更多
关键词 ECONOMIC FISH Heavy metal Muscle Liver evaluation
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Electrochemical Determination of Rate Constants for Reactions of OH and its Application in the Evaluation of Anti-Oxidant Actions of Rheum
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作者 Ruo Mei GAO Zhuo Bin YUAN Fu Ming Lm and Hong Bo DING(Department of Chemistry, Graduate School, USTC, Acaddria Sinica, Beijing 100039) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第5期427-430,共4页
A single-sweep oscillopolarographic procedure is descrital which allows detethenahon of rateconstants for reachons of oH. For a wide range of compounds, the results fit well with rate constantspreviously obtained with... A single-sweep oscillopolarographic procedure is descrital which allows detethenahon of rateconstants for reachons of oH. For a wide range of compounds, the results fit well with rate constantspreviously obtained with other methods. Rate constants for reactions of six kinds of active compoundscontalned in rheum, a tradihonal Chinese herb, have been deteboned by this method. Rcationmechanism ha5 also been discussed. 展开更多
关键词 OH Electrochemical determination of Rate Constants for Reactions of OH and its Application in the evaluation of Anti-Oxidant Actions of Rheum
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Factor value determination and applicability evaluation of universal soil loss equation in granite gneiss region
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作者 Wen-hai ZHANG Xing-nan ZHANG Zhi-dong GAO 《Water Science and Engineering》 EI CAS 2009年第2期87-97,共11页
Six types of runoff plots were set up and an experimental study was carried out to examine natural rate of soil and water loss in the granite gneiss region of northern Jiangsu Province in China. Through correlation an... Six types of runoff plots were set up and an experimental study was carried out to examine natural rate of soil and water loss in the granite gneiss region of northern Jiangsu Province in China. Through correlation analysis of runoff and soil loss during 364 rainfall events, a simplified and convenient mathematical formula suitable for calculating the rainfall erosivity factor (R) for the local region was established. Other factors of the universal soil loss equation (USLE model) were also determined. Relative error analysis of the soil loss of various plots calculated by the USLE model on the basis of the observed values showed that the relative error ranged from -3.5% to 9.9% and the confidence level was more than 90%. In addition, the relative error was 5.64% for the terraced field and 12.36% for the sloping field in the practical application. Thus, the confidence level was above 87.64%. These results provide a scientific basis for forecasting and monitoring soil and water loss, for comprehensive management of small watersheds, and for soil and water conservation planning in the region. 展开更多
关键词 granite gneiss region soil erosion universal soil loss equation factor value applicability evaluation
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Determination of Consistency between Quantitative Evaluation and Non-quantitative Evaluation
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作者 史倩 刘国华 《Journal of Donghua University(English Edition)》 CAS 2023年第3期334-342,共9页
The combination of quantitative evaluation(QE)and non-quantitative evaluation(NQE)is an important evaluation tool in the fields of academic level evaluation(e.g.,EasyChair,Academic paper review form)and internet commo... The combination of quantitative evaluation(QE)and non-quantitative evaluation(NQE)is an important evaluation tool in the fields of academic level evaluation(e.g.,EasyChair,Academic paper review form)and internet commodity evaluation(e.g.,Amazon’s review,Feedback).But the inconsistency between QE and NQE greatly reduces the correctness and usability of the evaluation.Therefore,it is a necessary task to judge whether QE is consistent with NQE.In this paper,the predicate formula satisfiability problem is firstly reduced in polynomial time to the consistency problem of QE and NQE,and the uncertainty of the consistency problem is proved.Then the approximate solution to the problem is investigated by using a natural language processing method,which performs sentiment analysis on NQE and finally invokes a database query statement to determine whether QE is consistent with NQE.The results shed light on the feasibility of using the natural language processing method to solve undecidable problems. 展开更多
关键词 quantitative evaluation(QE) non-quantitative evaluation(NQE) satisfiability problem natural language processing sentiment analysis
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Evaluation of Uncertainty in Determination of Ethyl Maltol in Vegetable Oil by Ultra-high Performance Liquid Chromatograph-Mass Spectrometer(UPLC-MS)
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作者 Lei ZHANG 《Agricultural Biotechnology》 CAS 2023年第3期113-115,共3页
[Objectives]This study was conducted to establish an uncertainty evaluation method for the determination of ethyl maltol by ultra-high performance liquid chromatograph-mass spectrometer(UPLC-MS).[Methods]A mathematica... [Objectives]This study was conducted to establish an uncertainty evaluation method for the determination of ethyl maltol by ultra-high performance liquid chromatograph-mass spectrometer(UPLC-MS).[Methods]A mathematical model of uncertainty was established by analyzing the method for determining ethyl maltol using UPLC-MS.The sources of uncertainty were analyzed,and the components of uncertainty were calculated to evaluate the expanded uncertainty of the method.[Results]When the content of ethyl maltol in edible vegetable oil was 1657μg/kg,the expanded uncertainty was 22.4μg/kg(K=2,P=95%).[Conclusions]The uncertainty in this evaluation model mainly came from standard solution preparation,sample weighing,dilution of sample to constant volume,standard curve fitting,and repeated measurement. 展开更多
关键词 Ultra-high performance liquid chromatograph-mass spectrometer determination Ethyl maltol Uncertainty
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Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat 被引量:1
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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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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network 被引量:1
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作者 Xue-Qiang Zhang Qing-Lin Cheng +2 位作者 Wei Sun Yi Zhao Zhi-Min Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期621-640,共20页
As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crud... As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems. 展开更多
关键词 Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction
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Landslide hazard susceptibility evaluation based on SBAS-InSAR technology and SSA-BP neural network algorithm:A case study of Baihetan Reservoir Area 被引量:1
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作者 GUO Junqi XI Wenfei +4 位作者 YANG Zhiquan SHI Zhengtao HUANG Guangcai YANG Zhengrong YANG Dongqing 《Journal of Mountain Science》 SCIE CSCD 2024年第3期952-972,共21页
Landslide hazard susceptibility evaluation takes on critical significance in early warning and disaster prevention and reduction.In order to solve the problems of poor effectiveness of landslide data and complex calcu... Landslide hazard susceptibility evaluation takes on critical significance in early warning and disaster prevention and reduction.In order to solve the problems of poor effectiveness of landslide data and complex calculation of weights for multiple evaluation factors in the existing landslide susceptibility evaluation models,in this study,a method of landslide hazard susceptibility evaluation is proposed by combining SBAS-InSAR(Small Baseline Subsets-Interferometric Synthetic Aperture Radar)and SSA-BP(Sparrow Search Algorithm-Back Propagation)neural network algorithm.The SBAS-InSAR technology is adopted to identify potential landslide hazards in the study area,update the cataloging data of landslide hazards,and 11 evaluation factors are chosen for constructing the SSA-BP model for training and validation.Baihetan Reservoir area is selected as a case study for validation.As indicated by the results,the application of SBAS-InSAR technology,combined with both ascending and descending orbit data,effectively addresses the incomplete identification of landslide hazards caused by geometric distortion of single orbit SAR data(e.g.,shadow,overlay,and perspective contraction)in deep canyon areas,thereby enabling the acquisition of up-to-date landslide hazard data.Moreover,in comparison to the conventional BP(Back Propagation)algorithm,the accuracy of the model constructed by the SSA-BP algorithm exhibits a significant increase,with mean squared error and mean absolute error reduced by 0.0142 and 0.0607,respectively.Additionally,during the process of susceptibility evaluation,the SSA-BP model effectively circumvents the issue of considerable manual interventions in calculating the weight of evaluation factors.The area under the curve of this model reaches 0.909,surpassing BP(0.835),random forest(0.792),and the information value method(0.699).The risk of landslide occurrence in the Baihetan Reservoir area is positively correlated with slope,surface temperature,and deformation rate,while it is negatively correlated with fault distance and normalized difference vegetation index.Geological lithology exerts minimal influence on the occurrence of landslides,with the risk being low in forest land and high in grassland.The method proposed in this study provides a useful reference for disaster prevention and mitigation departments to perform landslide hazard susceptibility evaluations in deep canyon areas under complex geological conditions. 展开更多
关键词 Baihetan SBAS-InSAR SSA-BP Landslide hazard susceptibility evaluation
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Comparative evaluation of commercial Douchi by different molds:biogenic amines,non-volatile and volatile compounds 被引量:1
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作者 Aijun Li Gang Yang +4 位作者 Zhirong Wang Shenglan Liao Muying Du Jun Song Jianquan Kan 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期434-443,共10页
To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fer... To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fermentation of Douchi.The results showed that the biogenic amine contents of the three types of Douchi were all within the safe range and far lower than those of traditional fermented Douchi.Aspergillus-type Douchi produced more free amino acids than the other two types of Douchi,and its umami taste was more prominent in sensory evaluation(P<0.01),while Mucor-type and Rhizopus-type Douchi produced more esters and pyrazines,making the aroma,sauce,and Douchi flavor more abundant.According to the Pearson and PLS analyses results,sweetness was significantly negatively correlated with phenylalanine,cysteine,and acetic acid(P<0.05),bitterness was significantly negatively correlated with malic acid(P<0.05),the sour taste was significantly positively correlated with citric acid and most free amino acids(P<0.05),while astringency was significantly negatively correlated with glucose(P<0.001).Thirteen volatile compounds such as furfuryl alcohol,phenethyl alcohol,and benzaldehyde caused the flavor difference of three types of Douchi.This study provides theoretical basis for the selection of starting strains for commercial Douchi production. 展开更多
关键词 DOUCHI Starting strains Non-volatile compounds Volatile compounds Sensory evaluation
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Identification and evaluation of shale oil micromigration and its petroleum geological significance 被引量:2
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作者 HU Tao JIANG Fujie +10 位作者 PANG Xiongqi LIU Yuan WU Guanyun ZHOU Kuo XIAO Huiyi JIANG Zhenxue LI Maowen JIANG Shu HUANG Liliang CHEN Dongxia MENG Qingyang 《Petroleum Exploration and Development》 SCIE 2024年第1期127-140,共14页
Taking the Lower Permian Fengcheng Formation shale in Mahu Sag of Junggar Basin,NW China,as an example,core observation,test analysis,geological analysis and numerical simulation were applied to identify the shale oil... Taking the Lower Permian Fengcheng Formation shale in Mahu Sag of Junggar Basin,NW China,as an example,core observation,test analysis,geological analysis and numerical simulation were applied to identify the shale oil micro-migration phenomenon.The hydrocarbon micro-migration in shale oil was quantitatively evaluated and verified by a self-created hydrocarbon expulsion potential method,and the petroleum geological significance of shale oil micro-migration evaluation was determined.Results show that significant micro-migration can be recognized between the organic-rich lamina and organic-poor lamina.The organic-rich lamina has strong hydrocarbon generation ability.The heavy components of hydrocarbon preferentially retained by kerogen swelling or adsorption,while the light components of hydrocarbon were migrated and accumulated to the interbedded felsic or carbonate organic-poor laminae as free oil.About 69% of the Fengcheng Formation shale samples in Well MY1 exhibit hydrocarbon charging phenomenon,while 31% of those exhibit hydrocarbon expulsion phenomenon.The reliability of the micro-migration evaluation results was verified by combining the group components based on the geochromatography effect,two-dimension nuclear magnetic resonance analysis,and the geochemical behavior of inorganic manganese elements in the process of hydrocarbon migration.Micro-migration is a bridge connecting the hydrocarbon accumulation elements in shale formations,which reflects the whole process of shale oil generation,expulsion and accumulation,and controls the content and composition of shale oil.The identification and evaluation of shale oil micro-migration will provide new perspectives for dynamically differential enrichment mechanism of shale oil and establishing a“multi-peak model in oil generation”of shale. 展开更多
关键词 shale oil micro-migration identification micro-migration evaluation Junggar Basin Mahu Sag Lower Permian Fengcheng Formation hydrocarbon expulsion potential method
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Method for evaluation of geological strength index of carbonate cliff rocks:Coupled hyperspectral-digital borehole image technique 被引量:1
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作者 Haiqing Yang Guizhong Huang +3 位作者 Chiwei Chen Yong Yang Qi Wang Xionghui Dai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4204-4215,共12页
The deterioration of unstable rock mass raised interest in evaluating rock mass quality.However,the traditional evaluation method for the geological strength index(GSI)primarily emphasizes the rock structure and chara... The deterioration of unstable rock mass raised interest in evaluating rock mass quality.However,the traditional evaluation method for the geological strength index(GSI)primarily emphasizes the rock structure and characteristics of discontinuities.It ignores the influence of mineral composition and shows a deficiency in assessing the integrity coefficient.In this context,hyperspectral imaging and digital panoramic borehole camera technologies are applied to analyze the mineral content and integrity of rock mass.Based on the carbonate mineral content and fissure area ratio,the strength reduction factor and integrity coefficient are calculated to improve the GSI evaluation method.According to the results of mineral classification and fissure identification,the strength reduction factor and integrity coefficient increase with the depth of rock mass.The rock mass GSI calculated by the improved method is mainly concentrated between 40 and 60,which is close to the calculation results of the traditional method.The GSI error rates obtained by the two methods are mostly less than 10%,indicating the rationality of the hyperspectral-digital borehole image coupled evaluation method.Moreover,the sensitivity of the fissure area ratio(Sr)to GSI is greater than that of the strength reduction factor(a),which means the proposed GSI is suitable for rocks with significant fissure development.The improved method reduces the influence of subjective factors and provides a reliable index for the deterioration evaluation of rock mass. 展开更多
关键词 Hyperspectral image Digital panoramic borehole image Geological strength index Carbonate rock mass Quantitative evaluation
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