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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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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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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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Application and Development Trends of Spectral Analysis in Draft of Non-Ferrous Metal Standards in China
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作者 Lijun Kuai Huachang Li +1 位作者 Jiemin Liu Shufang Tang 《American Journal of Analytical Chemistry》 2023年第6期239-273,共35页
Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of va... Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of various spectroscopic techniques, mainly including atomic absorption spectrometry (AAS) inductively coupled plasma emission spectrometry (ICP-AES) X-ray fluorescence spectroscopy (XRF) atomic fluorescence spectroscopy (AFS) direct reading spectroscopy (OES) glow discharge emission spectroscopy (GD-OSE) laser-induced breakdown spectroscopy (LIBS), in the formulation of non-ferrous metal standards in China. The AAS method was the most widely used single-element microanalysis method among the non-ferrous metal standards. The ICP-AES method was good at significant advantages in the simultaneous detection of multiple elements. The XRF method was increasingly used in the determination of primary and secondary trace elements due to its simple sample preparation and high efficiency. The AFS was mostly detected by single-element trace analysis. OES GD-OES and LIBS were playing an increasingly important role in the new demand area for non-ferrous metals. This paper discussed matrix elimination, sample digestion, sample preparation, instrument categories and other aspects of some standards, and summarized the advantages of spectral analysis and traditional chemical analysis methods. The new methods of future spectroscopic technology had been illustrated in the process of developing non-ferrous metal standards. 展开更多
关键词 Atomic Absorption Spectroscopy Inductively Coupled Plasma Emission Spectroscopy X-Ray Fluorescence Spectroscopy Atomic Fluorescence Spectroscopy Direct Reading Spectroscopy Glow Discharge Emission Spectroscopy Laser-Induced Breakdown Spectroscopy Non-Ferrous Metals standard methods Were Formulated
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Improved EEMD-based standardization method for developing long tree-ring chronologies 被引量:5
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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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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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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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A HPLC Method for the Determination of Salmon Calcitonin in Injection by Gradient Elution 被引量:1
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作者 陈小平 郭庆东 张强 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第2期114-116,共3页
It was concluded that the described HPLC method could be used for the assayof salmon calcitonin in injection, as it offers qualified selectivity, accuracy and precision ofanalysis.
关键词 HPLC ASSAY salmon calcitonin injection external standard method
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Analytical and Traveling Wave Solutions to the Fifth Order Standard Sawada-Kotera Equation via the Generalized exp(-Φ(ξ))-Expansion Method 被引量:1
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作者 M. Y. Ali M. G. Hafez +1 位作者 M. K. H. Chowdury M. T. Akter 《Journal of Applied Mathematics and Physics》 2016年第2期262-271,共10页
In this article, we propose a generalized exp(-Φ(ξ))-expansion method and successfully implement it to find exact traveling wave solutions to the fifth order standard Sawada-Kotera (SK) equation. The exact traveling... In this article, we propose a generalized exp(-Φ(ξ))-expansion method and successfully implement it to find exact traveling wave solutions to the fifth order standard Sawada-Kotera (SK) equation. The exact traveling wave solutions are established in the form of trigonometric, hyperbolic, exponential and rational functions with some free parameters. It is shown that this method is standard, effective and easily applicable mathematical tool for solving nonlinear partial differential equations arises in the field of mathematical physics and engineering. 展开更多
关键词 Generalized exp(-Φ(ξ))-Expansion method Fifth Order standard Sawada-Kotera Equation SOLITONS Periodic Wave Solutions
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中医医院新入职本科护士培训考核评价指标的构建 被引量:1
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作者 张岩 秦元梅 +3 位作者 刘姝 杨艳明 钟远 邹小燕 《中华护理教育》 CSCD 2024年第2期145-152,共8页
目的 构建中医医院新入职本科护士培训考核评价指标。方法 通过文献研究、小组讨论,建立中医医院新入职本科护士培训考核评价指标初稿,选取来自7个省份的中华护理学会中医中西医结合护理分会的15名专家进行2轮专家咨询,确定考核评价内... 目的 构建中医医院新入职本科护士培训考核评价指标。方法 通过文献研究、小组讨论,建立中医医院新入职本科护士培训考核评价指标初稿,选取来自7个省份的中华护理学会中医中西医结合护理分会的15名专家进行2轮专家咨询,确定考核评价内容及其权重。结果 2轮专家函询问卷的有效回收率均为100%,专家权威系数分别是0.962、0.980,肯德尔协调系数分别是0.220、0.268(均P<0.05),最终形成的中医医院新入职本科护士培训考核评价指标包括5项一级指标、24项二级指标和77项三级指标。结论 构建的中医医院新入职本科护士培训考核评价指标具有较高的可靠性和科学性,可为中医医院管理者及培训者选拔人才提供参考。 展开更多
关键词 教育 中医医院 新入职护士 规范化培训 考核 德尔菲法
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基于性能的通航桥梁抗船撞评估方法及应用研究 被引量:2
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作者 王永祥 贾小龙 孙红兰 《世界桥梁》 北大核心 2024年第1期95-102,共8页
为合理有效地开展通航桥梁抗船撞性能评估,提出基于性能的桥梁抗船撞标准化评估方法。基于现行《公路桥梁抗撞设计规范》(JTG/T 3360-02-2020),从抗撞性能等级确定、设防代表船型确定、船撞力计算、船撞效应计算以及抗撞性能验算等方面... 为合理有效地开展通航桥梁抗船撞性能评估,提出基于性能的桥梁抗船撞标准化评估方法。基于现行《公路桥梁抗撞设计规范》(JTG/T 3360-02-2020),从抗撞性能等级确定、设防代表船型确定、船撞力计算、船撞效应计算以及抗撞性能验算等方面,采用结构性能目标作为评估准则,建立桥梁抗撞性能评估各环节流程的标准化评估方法。以江苏扬中三桥为应用实例,运用该方法进行该桥20号墩抗撞性能评估,结果表明:20号墩桩基顺桥向抗弯性能不满足JX1级要求,其余验算结果满足要求,桥墩抗撞性能综合评估结果为不满足要求。参照评估结果该桥加装了浮动式防撞设施。桥梁抗撞性能评估标准化,可准确高效实现桥梁抗撞性能等级确定、船撞效应计算、抗撞性能验算等预期的评估功能要求。 展开更多
关键词 桥梁工程 船撞桥 现行规范 结构性能目标 抗撞性能 标准化评估方法 工程应用
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前维生素D相对校正因子的研究及测定
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作者 施洁明 王珵 +7 位作者 张立雯 董顺玲 乐健 袁松 陆益红 王丹丹 徐万魁 郑淑凤 《中国药品标准》 CAS 2024年第2期147-153,共7页
目的:测定前维生素D相对校正因子,简化维生素D含量测定的计算方法。方法:通过对各国药品标准中维生素D含量计算方法的研究,采用HPLC法测定前维生素D相对校正因子,并对测定的影响因素进行了考察。结果:统计了国内7家实验室的前维生素D相... 目的:测定前维生素D相对校正因子,简化维生素D含量测定的计算方法。方法:通过对各国药品标准中维生素D含量计算方法的研究,采用HPLC法测定前维生素D相对校正因子,并对测定的影响因素进行了考察。结果:统计了国内7家实验室的前维生素D相对校正因子的测定结果,确定了254 nm和265 nm 2个波长下的前维生素D相对校正因子。结论:采用前维生素D相对校正因子法计算维生素D的总量,简化了实验步骤,避免了随机操作误差。该方法快速、准确,为进一步提高维生素D制剂标准奠定了基础。 展开更多
关键词 维生素D 前维生素D 相对校正因子 影响因素 高效液相色谱 外标法
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高效液相色谱内标法测定海水叶绿素a浓度
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作者 李芝凤 杨安安 +1 位作者 韩冰 郭凯 《海洋技术学报》 2024年第4期56-62,共7页
叶绿素a浓度是海水水质监测和海洋赤潮预警的重要指标,高效液相色谱法作为叶绿素a浓度最准确的测量方法之一被广泛应用。本文选用β-阿朴-8’-胡萝卜素醛(β-Apocarotena-8’-carotenal,Apocarotenal)为内标物,建立了一种基于液相色谱... 叶绿素a浓度是海水水质监测和海洋赤潮预警的重要指标,高效液相色谱法作为叶绿素a浓度最准确的测量方法之一被广泛应用。本文选用β-阿朴-8’-胡萝卜素醛(β-Apocarotena-8’-carotenal,Apocarotenal)为内标物,建立了一种基于液相色谱内标法的海水叶绿素a浓度分析方法,在实验检测范围内,方法相关性良好,相关系数为0.9998,检出限为0.05μg/L,回收率为97.0%~100%,相对标准偏差为0.38%~0.55%,精密度良好。同时,利用实验室培养的小球藻藻液和现场海水样品对内标法和外标法进行了显著性差异评估。结果表明:两种方法不存在显著性差异,12组现场海水样品内标法和外标法的测定结果相关性良好,相关系数为0.92,平均相对误差为6.21%。液相色谱内标法测定海水叶绿素a浓度分离效果好、准确度高,能对实验室叶绿素a浓度的测量进行较为准确的质量控制。 展开更多
关键词 高效液相色谱 内标法 叶绿素A 显著性差异评估
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电感耦合等离子体质谱法测定复杂高温合金中微量硅
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作者 王丹 李思思 +3 位作者 李辉 郭莉莉 郭宏杰 张重远 《化学分析计量》 CAS 2024年第2期77-81,共5页
以混酸低温加热方式溶解合金,采用电感耦合等离子体质谱法测定复杂高温合金中微量硅。通过实验前准备、动能歧视和完全匹配基体消除二次污染、多原子离子干扰和共存元素干扰。采用5 mL盐酸、0.5 mL硝酸和几滴氢氟酸作溶剂,于80℃加热溶... 以混酸低温加热方式溶解合金,采用电感耦合等离子体质谱法测定复杂高温合金中微量硅。通过实验前准备、动能歧视和完全匹配基体消除二次污染、多原子离子干扰和共存元素干扰。采用5 mL盐酸、0.5 mL硝酸和几滴氢氟酸作溶剂,于80℃加热溶解合金样品,以Sc为内标校正仪器波动产生的影响。以硅的信号强度值为纵坐标,其质量分数为横坐标,绘制标准工作曲线,质量分数在0.002%~0.10%范围内线性良好,相关系数为0.999,检出限为0.0003%。样品加标平均回收率为90.0%~110.0%,测定结果的相对标准偏差不大于2.0%(n=6)。该方法操作简便,能够满足日常测试要求。 展开更多
关键词 电感耦合等离子体质谱法 标准加入法 复杂高温合金 微量硅
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