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Smart Society and Artificial Intelligence:Big Data Scheduling and the Global Standard Method Applied to Smart Maintenance 被引量:1
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作者 Ruben Foresti Stefano Rossi +2 位作者 Matteo Magnani Corrado Guarino Lo Bianco Nicola Delmonte 《Engineering》 SCIE EI 2020年第7期835-846,共12页
The implementation of artificial intelligence(AI)in a smart society,in which the analysis of human habits is mandatory,requires automated data scheduling and analysis using smart applications,a smart infrastructure,sm... The implementation of artificial intelligence(AI)in a smart society,in which the analysis of human habits is mandatory,requires automated data scheduling and analysis using smart applications,a smart infrastructure,smart systems,and a smart network.In this context,which is characterized by a large gap between training and operative processes,a dedicated method is required to manage and extract the massive amount of data and the related information mining.The method presented in this work aims to reduce this gap with near-zero-failure advanced diagnostics(AD)for smart management,which is exploitable in any context of Society 5.0,thus reducing the risk factors at all management levels and ensuring quality and sustainability.We have also developed innovative applications for a humancentered management system to support scheduling in the maintenance of operative processes,for reducing training costs,for improving production yield,and for creating a human–machine cyberspace for smart infrastructure design.The results obtained in 12 international companies demonstrate a possible global standardization of operative processes,leading to the design of a near-zero-failure intelligent system that is able to learn and upgrade itself.Our new method provides guidance for selecting the new generation of intelligent manufacturing and smart systems in order to optimize human–machine interactions,with the related smart maintenance and education. 展开更多
关键词 Smart maintenance Smart society Artificial intelligence Human-centered management system Big data scheduling Global standard method Society 5.0 Industry 4.0
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Quantitative Determination of Tetrachlorantraniliprole by(1)^H NMR Spectroscopy with Internal Standard Method
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作者 Lang Jie Dong Yan +2 位作者 Wang Qiang Yang Huibin Yu Haibo 《Plant Diseases and Pests》 CAS 2020年第5期35-37,共3页
[Objective]This study was to establish a rapid,specific and simple method for quantitative determination of tetrachlorantraniliprole by 1H NMR.[Method]1H NMR spectroscopy was acquired with deuterium DMSO as the solven... [Objective]This study was to establish a rapid,specific and simple method for quantitative determination of tetrachlorantraniliprole by 1H NMR.[Method]1H NMR spectroscopy was acquired with deuterium DMSO as the solvent and maleic acid as internal standard under the conditions of temperature 25℃,pulses width 8.0μs,delay time 5 s,and scanning times 8.[Result]The hydrogen proton peaks of tetrachlorantraniliprole(δ=10.55)and maleic acid(δ=6.27)were taken as quantitative peaks.The peak area ratio y(As/Ar)and mass ratio x(ms/mr)were linearly regressed,and the correlation coefficient was 0.9999.The RSD value of repeatability test was 0.38%,and the RSD value of stability test was 0.77%.The content of tetrachlorantraniliprole was determined as 99.6%.[Conclusion]1H NMR spectroscopy can be used for quantitative determination of tetrachlorantraniliprole without standard reference,which is rapid,accurate and simple. 展开更多
关键词 Tetrachlorantraniliprole qNMR Internal standard method Quantitative determination
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Application of internal standard method in recombinant luminescent bacteria test
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作者 Yong-zhi Wang Dan Li Miao He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第9期128-134,共7页
Mercury and its organic compounds have been of severe concern worldwide due to their damage to the ecosystem and human health. The development of effective and affordable technology to monitor and signal the presence ... Mercury and its organic compounds have been of severe concern worldwide due to their damage to the ecosystem and human health. The development of effective and affordable technology to monitor and signal the presence of bioavailable mercury is an urgent need.The Mer gene is a mercury-responsive resistant gene, and a mercury-sensing recombinant luminescent bacterium using the Mer gene was constructed in this study. The mer operon from marine Pseudomonas putida strain SP1 was amplified and fused with prompterless lux CDABE in the p UCD615 plasmid within Escherichia coli cells, resulting in p THE30–E. coli.The recombinant strain showed high sensitivity and specificity. The detection limit of Hg^2+was 5 nmol/L, and distinct luminescence could be detected in 30 min. Cd^2+, Cu^2+, Zn^2+, Ca^2+,Pb^2+, Mg^2+, Mn^2+, and Al^3+did not interfere with the detection over a range of 10-5–1 m M.Application of recombinant luminescent bacteria testing in environmental samples has been a controversial issue: especially for metal-sensing recombinant strains, false negatives caused by high cytotoxicity are one of the most important issues when applying recombinant luminescent bacteria in biomonitoring of heavy metals. In this study, by establishing an internal standard approach, the false negative problem was overcome;furthermore, the method can also help to estimate the suspected mercury concentration,which ensures high detection sensitivity of bioavailable Hg2+. 展开更多
关键词 Mercury Biomonitoring Recombinant luminescent bacteria p THE30–E.coli Internal standard method False negative
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Synthesis of an IS and Steviol Glycoside Analysis by a Validated Internal Standard Method
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作者 Jan M. C. Geuns Tom Struyf +2 位作者 Stijn Ceunen Gert Steurs Wim De Borggraeve 《American Journal of Analytical Chemistry》 2018年第11期547-559,共13页
The internal standard (IS) method is the best method for the analysis of samples, as it is independent of errors in injection volume, changes in sample volumes, and changes in sensitivity of the detector, etc. Use of ... The internal standard (IS) method is the best method for the analysis of samples, as it is independent of errors in injection volume, changes in sample volumes, and changes in sensitivity of the detector, etc. Use of an internal standard allows for the correction of losses due to sample clean-up of complex samples. An ideal IS is a compound that has properties very similar to, and that behaves as the compounds to be analysed. Ideally, only in the last step of analysis (HPLC), the IS should be well separated from the compounds of the mixture to be analysed. After testing several existing compounds with negative results, we decided to synthesise the 19-O-β-D-galactopyranosyl-13-O-β-D-glucopyranosyl-steviol as IS. This is the 19-galactosyl ester of steviolmonoside (13-O-β-D-glucopyranosyl-steviol). The IS was made according to published methods. Steviolmonoside (SM) was made from purified commercial rubusoside (Rub) by refluxing it in 10% KOH for 2 h. SM was precipitated and crystallized from MeOH. The hydroxyls of the glucose unit of SM were protected by acetylation. The acetylated SM was crystallized from acetone and dissolved in 1,2-dichloroethane. Then Ag2CO3 on Celite and tetra-acetylated galactopyranosyl bromide were added and the mixture was refluxed for 2 h. After cooling, BaO in MeOH was added to remove the acetyl groups. The 1,2-dichloroethane fraction was then extracted three times with equal volumes of water and the water fraction containing the IS was further purified on a C18 flash chromatography column. Traces of unreacted SM were removed by preparative HPLC on an Alltima C18 column (250 mm × 22 mm, particle size 10 μm) with AcCN:water (35:65, 20 ml/min). Detection was at 210 nm (KNAUER, “Smartline” UV detector 2500). The collected IS fraction from the HPLC was completely dried. Mixtures of steviol glycosides (SVglys) containing IS could be purified over SPE cartridges without change of the SVgly over IS ratio. The calibration curves for rebaudioside A (RebA) and stevioside (ST) were linear between 0.012 and 0.95 and between 0.013 and 1.13 mM for RebA and ST, respectively. The accuracy was checked by the standard addition method. It was concluded that the IS method gives an excellent precision and accuracy. 展开更多
关键词 STEVIOL GLYCOSIDES INTERNAL standard method VALIDATION Quantification PURIFICATION
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Optimal Scheduling of an Independent Electro-Hydrogen System with Hybrid Energy Storage Using a Multi-Objective Standardization Fusion Method
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作者 Suliang Ma Zeqing Meng +1 位作者 Mingxuan Chen Yuan Jiang 《Energy Engineering》 EI 2025年第1期63-84,共22页
In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is crucial.Still,it presents a challenge due to the significant deviations in values ofmultiple optimizatio... In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is crucial.Still,it presents a challenge due to the significant deviations in values ofmultiple optimization objective functions caused by their physical dimensions.These deviations seriously affect the scheduling process.A novel standardization fusion method has been established to address this issue by analyzing the variation process of each objective function’s values.The optimal scheduling results of IEHS with HESS indicate that the economy and overall energy loss can be improved 2–3 times under different optimization methods.The proposed method better balances all optimization objective functions and reduces the impact of their dimensionality.When the cost of BESS decreases by approximately 30%,its participation deepens by about 1 time.Moreover,if the price of the electrolyzer is less than 15¥/kWh or if the cost of the fuel cell drops below 4¥/kWh,their participation will increase substantially.This study aims to provide a more reasonable approach to solving multi-objective optimization problems. 展开更多
关键词 Electro-hydrogen system multi-objective optimization standardization method hybrid energy storage system
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Improved EEMD-based standardization method for developing long tree-ring chronologies 被引量:6
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作者 Xianliang Zhang Junxia Li +1 位作者 Xiaobo Liu Zhenju Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第6期2217-2224,共8页
Long tree-ring chronologies can be developed by overlapping data from living trees with data from fossil trees through cross-dating.However,low-frequency climate signals are lost when standardizing tree-ring series du... Long tree-ring chronologies can be developed by overlapping data from living trees with data from fossil trees through cross-dating.However,low-frequency climate signals are lost when standardizing tree-ring series due to the"segment length curse".To alleviate the segment length curse and thus improve the standardization method for developing long tree-ring chronologies,here we first calculated a mean value for all the tree ring series by overlapping all of the tree ring series.The growth trend of the mean tree ring width(i.e.,cumulated average growth trend of all the series)was determined using ensemble empirical mode decomposition.Then the chronology was developed by dividing the mean value by the growth trend of the mean value.Our improved method alleviated the problem of trend distortion.Long-term signals were better preserved using the improved method than in previous detrending methods.The chronologies developed using the improved method were better correlated with climate than those developed using conservative methods.The improved standardization method alleviates trend distortion and retains more of the low-frequency climate signals. 展开更多
关键词 standardization methods Tree rings Segment length curse DETRENDING
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Interpretation of the national standard GB/T 43778-2024 on determination of styrene and 2-chloroethanol in cell culture medium
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作者 Chen Chun Zhou Zuanzuan Ye Sudan 《China Standardization》 2024年第S1期42-45,共4页
Plastic equipment used in cell culture processes contains styrene residues and 2-chloroethanol, a byproduct of ethylene oxide sterilization. Both compounds can have long-term effects on the quality and safety of the c... Plastic equipment used in cell culture processes contains styrene residues and 2-chloroethanol, a byproduct of ethylene oxide sterilization. Both compounds can have long-term effects on the quality and safety of the cells in plastic equipment. GB/T 43778-2024, which establishes a gas chromatography-mass spectrometry(GC-MS) method for the simultaneous detection of st yrene and 2-chloroethanol in cell culture media, includes several technical requirements that need to be thoroughly interpreted. This paper provides a detailed explanation of the internal standard calibration method used for detecting styrene and 2-chloroethanol, covering the overall framework and innovation aspects of the standard. Additionally, it elucidates the principles and rationale of each step, including sample processing, detection parameters, preparation of standard solutions, and the determination of detection and quantification limits, to assist testing technical staff in applying the method effectively. 展开更多
关键词 STYRENE 2-chloroethanol internal standard method cell culture gas chromatography-mass spectrometry
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Using Different Standardized Methods for Species Identification:A Case Study Using Beaks from Three Ommastrephid Species 被引量:4
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作者 HU Guanyu FANG Zhou +3 位作者 LIU Bilin CHEN Xinjun STAPLES Kevin CHEN Yong 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第2期355-362,共8页
The cephalopod beak is a vital hard structure with a stable configuration and has been widely used for the identification of cephalopod species. This study was conducted to determine the best standardization method fo... The cephalopod beak is a vital hard structure with a stable configuration and has been widely used for the identification of cephalopod species. This study was conducted to determine the best standardization method for identifying different species by measuring 12 morphological variables of the beaks of Illex argentinus, Ommastrephes bartramii, and Dosidicus gigas that were collected by Chinese jigging vessels. To remove the effects of size, these morphometric variables were standardized using three methods. The average ratios of the upper beak morphological variables and upper crest length of O. bartramii and D. gigas were found to be greater than those of I. argentinus. However, for lower beaks, only the average of LRL(lower rostrum length)/LCL(lower crest length), LRW(lower rostrum width)/LCL, and LLWL(lower lateral wall length)/LCL of O. bartramii and D. gigas were greater than those of I. argentinus. The ratios of beak morphological variables and crest length were found to be all significantly different among the three species(P < 0.001). Among the three standardization methods, the correct classification rate of stepwise discriminant analysis(SDA) was the highest using the ratios of beak morphological variables and crest length. Compared with hood length, the correct classification rate was slightly higher when using beak variables standardized by crest length using an allometric model. The correct classification rate of the lower beak was also found to be greater than that of the upper beak. This study indicates that the ratios of beak morphological variables to crest length could be used for interspecies and intraspecies identification. Meanwhile, the lower beak variables were found to be more effective than upper beak variables in classifying beaks found in the stomachs of predators. 展开更多
关键词 BEAK standardized methodS DISCRIMINANT analysis Illex argentinus Ommastrephes bartramii Dosidicus GIGAS
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Design Method of Equipment Optimization Development Based on Standardization Theory 被引量:2
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作者 Lv-bo MAI 《Defence Technology(防务技术)》 SCIE EI CAS 2013年第3期140-145,共6页
The matters of equipment optimization development are usually discrete,fuzzy and non-quantitative.It is difficult directly to optimize the equipment development with a mathematical model.A set of methods for designing... The matters of equipment optimization development are usually discrete,fuzzy and non-quantitative.It is difficult directly to optimize the equipment development with a mathematical model.A set of methods for designing the equipment optimization development with six dimensions and eight main elements is established based on the theory and method of standardization.The top-tier design space of systematic development of equipment is built up by the relations of basic models,series and model spectrums.The relations of time and space for equipment optimization development are established.The design processes of a six dimension systematic space are expounded.The connotation of each plan in the main system space is analyzed.A design method for an entire equipment is established with standardization theory.The coordinating design methods of equipment technical system and the optimization design methods of equipment integration are discussed.The design methods for universalization and serialization of components and parts are established.The design methods of equipment optimization development highlight the relations of the basic model of platform,the serialization of platform basic models,the modularization of equipment functions,the model spectrum of variant equipment,and the universalization and serialization of components and parts. 展开更多
关键词 优化设计方法 优化开发 化设备 标准化 优化发展 数学模型 设计空间 设备系统
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The Research on Methodology for Material Code Standardization in the Implementation of MRP-Ⅱ
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作者 孙虞 《Journal of Southeast University(English Edition)》 EI CAS 1996年第2期13-18,共6页
This paper analyses the current common problems of material code standardization in the implementation of MRP Ⅱ, and puts forward the basic ideas and methods for solving the problems, which has some reference value ... This paper analyses the current common problems of material code standardization in the implementation of MRP Ⅱ, and puts forward the basic ideas and methods for solving the problems, which has some reference value for the popularization of application o 展开更多
关键词 CODING standard methods
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LA-ICP-MS Calibrations for Intact Rock Samples with Internal Standard and Modified Constant-Sum Methods
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作者 Sheng Peng Qinhong Hu 《American Journal of Analytical Chemistry》 2012年第2期168-174,共7页
Laser ablation coupled with inductively coupled plasma-mass spectrometry (LA-ICP-MS) calibration was conducted with multiple spot analyses on eleven intact rock samples using both an internal standard (IS) method and ... Laser ablation coupled with inductively coupled plasma-mass spectrometry (LA-ICP-MS) calibration was conducted with multiple spot analyses on eleven intact rock samples using both an internal standard (IS) method and a modified constant-sum (MCS) method. Methods were then compared for reported bulk elemental composition of the rocks. The MCS method was based on the sum of eight major elements, which is spatially more stable than one single major ele-ment as used in the IS method, and is quite constant among different rock samples. Calibrations were performed with standard reference materials NIST SRM 610, 612, 614, and 616. Little difference was found between using a single standard and a set of standards, because of the good linearity shown by the reference materials. Comparison of the two calibration methods shows that the MCS method produced better and more stable results than the IS method for heterogeneous samples. With the MCS method, approximately 94% to 95% of the total measurements are within the range of ±100% relative deviation, compared with 82% to 86% with the IS method. The IS method resulted insubstantial overestimations for some rock samples (e.g., 648% for Basalt BCR-2 using NIST SRM 610 as the calibration standard), while the largest deviation with the MCS method was 216% for U in Eagle Ford shale #80 sample. For Quartz latite QLO-1, a relative homogeneous sample, the IS method generated slightly better results than the MCS method. Regardless of method, spatially heterogeneous distribution of elements in the intact rock at the scale of the laser spot is considered to be the main reason for the large relative deviations seen in our work compared to published results. 展开更多
关键词 LA-ICP-MS Quantitative Calibration Internal standard method MODIFIED Constant-Sum method
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Simultaneous Determination of Uranium and Thorium with Standard Dual-addition Method
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作者 何荣桓 王建华 王玉宝 《Rare Metals》 SCIE EI CAS CSCD 1998年第2期75-80,共6页
dual-standard addition method was proposed and the principle of simultaneous determination for a interfering binary mixtures was discussed. The proposed procedure was applied to spectroscopic analyses for the simultan... dual-standard addition method was proposed and the principle of simultaneous determination for a interfering binary mixtures was discussed. The proposed procedure was applied to spectroscopic analyses for the simultaneous determination of uranium and thorium without prior separation. Various molar ratios of uranium/thorium, from 0.5∶1 to 10∶1, can be determined with satisfactory precision and accuracy. Uranium and thorium content in a phosphate ore and simulated sample were determined, the recoveries were 98.4%~102.5% for uranium and 96.8%~102.3% for thorium, the relative standard deviations (R.S.D) were 1.5%~2.3% for uranium and 2.1%~3.1% for thorium. 展开更多
关键词 Dual-standard addition method Simultaneous determination URANIUM THORIUM Spectroscopic analysis
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The Measurement and Uncertainty Analysis of Antenna Factor of Microwave Antennas Based on Standard Site Method
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作者 Chaochan Chen Hong Shi +1 位作者 Yi Miao Yu Sang 《International Journal of Communications, Network and System Sciences》 2017年第5期138-145,共8页
A method of Standard Site Method (SSM) in the American National Standards Institute’s ANSI C63.5 is described in the frequency ranges from 30 MHz to 1000 MHz. And a measurement system is set up for determining antenn... A method of Standard Site Method (SSM) in the American National Standards Institute’s ANSI C63.5 is described in the frequency ranges from 30 MHz to 1000 MHz. And a measurement system is set up for determining antenna factors (AF) of antennas on an Open Area Test Sites (OATS). AF of antennas including log-periodic antenna and biconical antenna is measured with SSM method by Shanghai Institute of Measurement and Testing Technology (SIMT), which shows good agreement to data measured by National Institute of Metrology (NIM). In the end, it analyzes the measurement uncertainty of SIMT in the 30 MHz to 1000 MHz frequency band and does comparison to that of NIM. 展开更多
关键词 ANTENNA FACTORS standard SITE method (SSM) MEASUREMENT UNCERTAINTY
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Evaluation of Application Value of Improved Standard Collection Method in Sputum Bacterial Test
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作者 MI Xiaomei YANG Wenjun 《外文科技期刊数据库(文摘版)医药卫生》 2021年第12期104-106,共5页
Objective: to study the effect of improved standard collection method in sputum bacterial test. Methods: 82 patients with acute attack of bronchitis received in our hospital from October 2018 to October 2019 were sele... Objective: to study the effect of improved standard collection method in sputum bacterial test. Methods: 82 patients with acute attack of bronchitis received in our hospital from October 2018 to October 2019 were selected for sputum bacterial test.Based on the order of admission, 41 cases in the reference group were given routine expectoration collection method;41 cases in the observation group were treated with improved standard collection method, and the test results of the two groups were compared. Results: ① The qualified rate of sputum samples in the observation group was statistically different from that in the reference group (P < 0.05).② The positive rate of sputum culture in the observation group was significantly different from that in the reference group (P < 0.05).③ There were differences in the collection time of samples and the operation time of sputum bacteriological test between the two groups (P < 0.05).Conclusion: the application of improved standard collection method in sputum bacterial test can improve the positive rate and shorten the time of practical operation. 展开更多
关键词 improved standard acquisition method sputum bacterial test application value
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Compilation Principles and Methods of China’s First Mongolian Standard in Meteorological Industry
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作者 Ying Chun Yu Gang Han Yanli 《Meteorological and Environmental Research》 CAS 2019年第4期118-121,共4页
Mongolian Terms Commonly Used in Meteorological Services that was issued by the China Meteorological Administration is China s first traditional Mongolian standard in meteorological industry. In the process of formula... Mongolian Terms Commonly Used in Meteorological Services that was issued by the China Meteorological Administration is China s first traditional Mongolian standard in meteorological industry. In the process of formulation, the compilation unit fully complied with the principles of scientificity, practicability, universality and versatility, and used literal translation, free translation, and the combination of literal translation and free translation to translate and compile 71 mongolian terms commonly used in meteorological services. The standard fills the blank of standardization construction of basic traditional Mongolian language in the meteorological industry of China. 展开更多
关键词 METEOROLOGY MONGOLIAN language standard COMPILATION PRINCIPLES and methodS
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基于德尔菲法的冠心病中医症状术语标准化研究 被引量:2
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作者 倪菲 袁东超 +3 位作者 杨茗茜 陈彦君 曲金桥 李可大 《中华中医药学刊》 北大核心 2025年第2期52-57,共6页
目的基于文献研究法并遵循术语标准化工作原则,运用德尔菲法初步形成冠心病中医症状术语专家共识,为其中医症状术语标准的形成和临床辨治研究奠定基础。方法根据前期文献研究结果,运用德尔菲法编制专家问卷,内容主要包括冠心病中医四诊... 目的基于文献研究法并遵循术语标准化工作原则,运用德尔菲法初步形成冠心病中医症状术语专家共识,为其中医症状术语标准的形成和临床辨治研究奠定基础。方法根据前期文献研究结果,运用德尔菲法编制专家问卷,内容主要包括冠心病中医四诊类症状术语条目等。通过电子形式发放三轮问卷,并将问卷结果录入微软Office Excel 2021,建立数据库后导入IBM SPSS Statistics 26.0统计软件,遴选了国内30多位中医术语标准化和中医心系病研究领域的专家。统计分析专家的积极与权威程度、专家意见的集中性与协调性等各方面指标。结果三轮电子调查问卷的专家积极程度系数分别为85.71%、91.43%和100.00%,专家权威程度系数均值为0.86,表明权威性较高;前两轮德尔菲专家咨询的肯德尔和谐系数均在0.2~0.5,第二轮专家一致性系数高于第一轮,接近0.5,且两轮肯德尔和谐系数卡方检验的P值均小于0.01,表明专家意见逐渐集中统一;第3轮问卷专家积极提出书面建议,经课题组研判均予以采纳。结论经过前期文献研究和三轮专家调查问卷,初步得出冠心病四诊类中医症状术语名称、英文对应词及术语定义。综合来看,采用德尔菲法流程规范,结果科学可靠,基本达成冠心病中医症状术语专家共识。 展开更多
关键词 冠心病 中医症状术语 德尔菲法 标准化
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直接甲酯化法测定特膳食品中脂肪酸含量 被引量:2
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作者 张协光 岑干君 +5 位作者 张柳青 林宇豪 杨华瑞 蓝雄 滕明攀 甘旺 《分析科学学报》 北大核心 2025年第1期65-72,共8页
针对特殊膳食用食品,研究并改进了乙酰氯-甲醇法,实现了对特膳食品中脂肪酸的快速、准确测定。样品加入十一碳酸甘油三酯(C11:0 TAG)内标溶液后,在5%乙酰氯-甲醇溶液和70℃水浴的条件下衍生90 min,然后使用6%碳酸钠溶液中和余酸,离心取... 针对特殊膳食用食品,研究并改进了乙酰氯-甲醇法,实现了对特膳食品中脂肪酸的快速、准确测定。样品加入十一碳酸甘油三酯(C11:0 TAG)内标溶液后,在5%乙酰氯-甲醇溶液和70℃水浴的条件下衍生90 min,然后使用6%碳酸钠溶液中和余酸,离心取上清液,经气相色谱仪分析,采用内标法定量。结果表明,各脂肪酸在一定浓度范围内线性关系良好,相关系数均大于0.999,方法检出限为0.0005 g/100g,定量限为0.002 g/100g。在不同基质的样品中进行了低、中、高浓度的加标实验,3个加标水平下的回收率在90.0%~110%之间,相对标准偏差(RSD)均小于10%。将该方法应用于6种不同基质的特殊膳食用食品脂肪酸的检测,测定结果与国标方法一致,RSD均小于10%。该方法简单快速,精密度和准确度高,样品量消耗少,适用于特殊膳食用食品中脂肪酸的检测。 展开更多
关键词 特殊膳食用食品 脂肪酸 乙酰氯-甲醇法 气相色谱 内标法
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老年期抑郁障碍规范治疗的德尔菲法专家共识调查研究 被引量:1
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作者 李志营 国灿灿 +4 位作者 周佳男 刘肇瑞 陈静宁 于欣 孙新宇 《中国医学前沿杂志(电子版)》 北大核心 2025年第3期96-101,共6页
目的 本研究运用德尔菲法构建老年期抑郁障碍(late-life depression,LLD)规范治疗的专家共识,旨在整合专家意见,为老年期抑郁障碍临床治疗提供参考依据,以提升治疗的规范性与有效性。方法 于2024年7—11月遴选全国15个省(自治区、直辖市... 目的 本研究运用德尔菲法构建老年期抑郁障碍(late-life depression,LLD)规范治疗的专家共识,旨在整合专家意见,为老年期抑郁障碍临床治疗提供参考依据,以提升治疗的规范性与有效性。方法 于2024年7—11月遴选全国15个省(自治区、直辖市)31名老年临床精神科专家,进行两轮问卷调查。问卷涵盖老年期抑郁障碍治疗的多方面内容,如治疗原则、药物选择、心理治疗等。运用描述性统计分析方法剖析专家基本信息、意见集中程度,对问卷各项目实施频数分析,从而提炼出规范化治疗的指导意见。结果 两轮共有31名老年临床精神科专家参与,涉及15个省(自治区、直辖市),均为副高及以上职称,平均年龄52岁,平均从业27.9年,其中精神专科医院20名,综合医院精神科10名,其他1名,两轮调查积极系数达96.77%。在老年期抑郁障碍规范治疗方面达成专家共识,如老年期抑郁障碍治疗应安全(100.00%)、有效(83.33%);心理治疗推荐支持治疗(93.33%)、问题解决治疗(83.33%);药物治疗原则应小剂量起始(93.33%)、尽量单一用药(90.00%);如果首选的抗抑郁药物无效,下一步的药物方案调整为现有药物加量(83.33%)或更换不同类型抗抑郁药物(83.33%)。针对不同类型老年期抑郁障碍的药物推荐达成共识,如首发抑郁障碍中推荐舍曲林(100.00%)等。然而,在合并用药时机、特殊治疗方法应用细节等方面仍存在争议。结论 本研究在老年期抑郁障碍的治疗原则,药物选择,合并用药方案及心理治疗的应用等多个存在分歧的领域达成了共识,为进一步深入研究和临床决策提供了有价值的参考和指导。 展开更多
关键词 老年期抑郁障碍 规范治疗 德尔菲法 专家共识
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农业生态补偿标准的量化方法研究与展望 被引量:3
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作者 乔玉辉 甄华杨 +1 位作者 冯旭 鞠鲤懋 《中国生态农业学报(中英文)》 北大核心 2025年第4期783-793,共11页
生态农业是实现农业可持续发展目标的核心路径之一,但是其发展面临着私人短期经济利益和公共长期生态效益的矛盾。农业生态补偿是化解这一矛盾的重要手段,农业生态补偿标准核算方法则是建立合理生态补偿机制的核心。目前,农业生态补偿... 生态农业是实现农业可持续发展目标的核心路径之一,但是其发展面临着私人短期经济利益和公共长期生态效益的矛盾。农业生态补偿是化解这一矛盾的重要手段,农业生态补偿标准核算方法则是建立合理生态补偿机制的核心。目前,农业生态补偿核算存在着农产品生态价值未被有效识别、核算体系不完善、服务价值与负服务价值未有机结合等核心科学问题。因此,当前亟须建立一套基于农业生态系统服务价值和负服务价值的农业生态补偿标准核算方法,以更好地支持农业生态补偿政策实施,并指导农业生态系统管理。本文提出了一个综合的农业生态补偿标准核算框架,主要包括生态保护成本、经济收益以及农业生态系统服务价值与负服务价值等,并详细介绍了农业生态系统服务的评估指标体系、价值化方法及负服务价值的核算方法,以此为农业生态补偿标准的确定提供理论支持与方法指导。本文从经济成本、相对生态价值和农业生态补偿情景分析等角度探讨了农业生态补偿标准的确定,旨在为各地制定科学合理的农业生态补偿标准提供参考。最后,本文展望了未来农业生态补偿标准核算研究的发展方向,包括生命周期综合生态系统服务价值评估、区域差异化管理以及学术研究与实践应用结合等方面,以期为未来农业生态补偿政策的制定与实施提供理论和方法支撑,促进农业生产与生态环境保护协调发展。 展开更多
关键词 生态补偿 生态农业 补偿标准 量化方法
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我国宠物饲料安全风险及监管中亟待解决的问题 被引量:1
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作者 孙国荣 陈磊 +1 位作者 金琦琦 周静 《中国饲料》 北大核心 2025年第1期153-156,共4页
近年来,我国宠物饲料行业发展的规模和速度惊人,市场份额不断增大,同时也显露出不少问题。本文侧重于宠物饲料质量安全,从宠物营养要求特点出发,对存在的有害微生物、霉菌毒素、药物及添加剂、有毒有害元素等风险因素进行分析总结,同时... 近年来,我国宠物饲料行业发展的规模和速度惊人,市场份额不断增大,同时也显露出不少问题。本文侧重于宠物饲料质量安全,从宠物营养要求特点出发,对存在的有害微生物、霉菌毒素、药物及添加剂、有毒有害元素等风险因素进行分析总结,同时提出质量安全监管中限量标准、检测方法和监管体系中存在的亟待解决的问题,希望对生产加工、科研开发、监管工作提供参考。 展开更多
关键词 宠物饲料 质量安全 风险因素 限量标准 检测方法 风险监管
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