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Review of AVS Audio Coding Standard
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作者 ZHANG Tao ZHANG Caixia ZHAO Xin 《ZTE Communications》 2016年第2期56-62,共7页
Audio Video Coding Standard (AVS) is a second-generation source coding standard and the first standard for audio and video coding in China with independent intellectual property rights. Its performance has reached t... Audio Video Coding Standard (AVS) is a second-generation source coding standard and the first standard for audio and video coding in China with independent intellectual property rights. Its performance has reached the international standard. Its coding efficiency is 2 to 3 times greater than that of MPEG -2. This technical solution is more simple, and it can greatly save channel resource. After more than ten years' development, AVS has achieved great success. The latest version of the AVS audio coding standard is ongoing and mainly aims at the increasing demand for low bitrate and high quality audio services. The paper reviews the history and recent development of AVS audio coding standard in terms of basic features, key techniques and performance. Finally, the future development of AVS audio coding standard is discussed. 展开更多
关键词 Audio Video coding standard (AVS) audio coding AVS1 au-dio AVS2 audio
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Effects of Mapping Methods on Accuracy of Protein Coding Regions Prediction
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作者 马玉韬 张成 +2 位作者 杨泽林 李琦 杨婷 《Agricultural Science & Technology》 CAS 2011年第12期1802-1806,1860,共6页
[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlatio... [Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlation(AC) as the full measure of the prediction accuracy at nucleotide level,the windowed narrow pass-band filter(WNPBF) based prediction algorithm was applied to study the effects of different mapping methods on prediction accuracy.[Result] In DNA data sets ALLSEQ and HMR195,the Voss and Z-Curve methods are proved to be more effective mapping methods than paired numeric(PN),Electron-ion Interaction Potential(EIIP) and complex number methods.[Conclusion] This study lays the foundation to verify the effectiveness of new mapping methods by using the predicted AC value,and it is meaningful to reveal DNA structure by using bioinformatics methods. 展开更多
关键词 Prediction accuracy Protein coding regions Mapping method Windowed Narrow pass-band filter
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Complying with Coding Standards or Retaining Programming Style: A Quality Outlook at Source Code Level
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作者 Yanqing Wang Bo Zheng Hujie Huang 《Journal of Software Engineering and Applications》 2008年第1期88-91,共4页
In order to make most software engineers and managers pay more attention to software quality at source level, two confusing terms-coding standard and programming style-were reviewed and compared. An evolutionary model... In order to make most software engineers and managers pay more attention to software quality at source level, two confusing terms-coding standard and programming style-were reviewed and compared. An evolutionary model of quality assurance at source code level was proposed, which implies that coding standard should be better accepted and more emphasized than programming style. Our current researches on evaluating the compliance with coding standards will likely make the strategy of quality assurance at source code level more operable. 展开更多
关键词 coding standards PROGRAMMING Style Source Code QUALITY ASSURANCE (QA) Evaluation Index System
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Very Low Bit-Rate Video Coding by Combining H.264/AVC Standard and 2-D Discrete Wavelet Transform
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作者 Ali Aghagolzadeh Saeed Meshgini +1 位作者 Mehdi Nooshyar Mehdi Aghagolzadeh 《Wireless Sensor Network》 2010年第4期328-336,共9页
In this paper, we propose a new method for very low bit-rate video coding that combines H.264/AVC standard and two-dimensional discrete wavelet transform. In this method, first a two dimensional wavelet transform is a... In this paper, we propose a new method for very low bit-rate video coding that combines H.264/AVC standard and two-dimensional discrete wavelet transform. In this method, first a two dimensional wavelet transform is applied on each video frame independently to extract the low frequency components for each frame and then the low frequency parts of all frames are coded using H.264/AVC codec. On the other hand, the high frequency parts of the video frames are coded by Run Length Coding algorithm, after applying a threshold to neglect the low value coefficients. Experiments show that our proposed method can achieve better rate-distortion performance at very low bit-rate applications below 16 kbits/s compared to applying H.264/AVC standard directly to all frames. Applications of our proposed video coding technique include video telephony, video-conferencing, transmitting or receiving video over half-rate traffic channels of GSM networks. 展开更多
关键词 Video coding H.264/AVC standard RUN Length coding Two-Dimensional WAVELET Transform
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Inspiration of Foreign Innovative Drug Pricing Methods and Medical Insurance Payment Standards to China
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作者 Rao Xiuli Sun Lihua 《Asian Journal of Social Pharmacy》 2023年第4期365-373,共9页
Objective To study the innovative drug pricing methods and medical insurance payment standards in foreign countries and to provide reference for China’s government.Methods The official websites were searched for info... Objective To study the innovative drug pricing methods and medical insurance payment standards in foreign countries and to provide reference for China’s government.Methods The official websites were searched for information and related literature,and literature review was used.Results and Conclusion In foreign countries,the clinical value of innovative drugs and their impact on medical insurance funds were comprehensively evaluated based on factors such as quality-adjusted life years,clinical benefit,and improvement of clinical benefit.Then,the evaluation results were taken as an important basis for whether innovative drugs were admitted to the medical insurance catalog and establishing medical insurance payment standards.By using international experience for reference,innovative drug pricing methods and medical insurance payment standards for China’s national conditions can be improved by establishing a basic database of clinical value and drug economic evaluation of innovative drugs,as well as innovative drug payment models based on decision thresholds. 展开更多
关键词 innovative drug pricing method payment standard medical insurance international experience
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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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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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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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Effectiveness of Participatory Teaching Methods in the Standardized Training of Respiratory Medicine Residents
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作者 Yanbing Wang Jieru Feng 《Journal of Contemporary Educational Research》 2023年第10期179-184,共6页
Objective:To explore and analyze the application effect of participatory teaching method in the standardized training of respiratory medicine residents.Methods:The study period was from May 2022 to May 2023.20 doctors... Objective:To explore and analyze the application effect of participatory teaching method in the standardized training of respiratory medicine residents.Methods:The study period was from May 2022 to May 2023.20 doctors in the standardized training of respiratory medicine residency in our hospital were taken as research subjects and grouped into the participatory group(n=10)and the routine group(n=10)by using the random number lottery method.The participatory group practised participatory teaching methods,and the routine group practised routine teaching methods.The results of discharge assessment,teaching evaluation,and mini-Clinical Evaluation Exercise(mini-CEX)assessment were compared between the groups.Results:The theoretical assessment,operational assessment,and total scores of the participatory group were significantly higher than those of the routine group,and the difference was statistically significant(P<0.05).The teaching evaluation of independent learning,theoretical mastery,teamwork,clinical thinking,communication,and learning interest of the participatory group was significantly higher than that of the routine group,and the difference was statistically significant(P<0.05).The mini-CEX assessments of history inquiry,organizational effectiveness,professionalism,physical examination,clinical diagnosis,communication skills,and overall clinical competence of the participatory group were significantly better than those of the routine group,and the difference was statistically significant(P<0.05).The teaching satisfaction of the participatory group was significantly higher than that of the routine group,the difference was statistically significant(P<0.05).Conclusion:Participatory teaching methods can improve the overall level of doctors in the respiratory medicine residency standardized training,and the teaching satisfaction is improved. 展开更多
关键词 Participatory teaching method Respiratory medicine RESIDENCY standardized training
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A Comprehensive Study on Application and Prospect of Hydrogel Detection Methods
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作者 Caixia Chen Pengyu Liu +3 位作者 Changhua Wang Yanyan Xie Wei Wang Xiaomin Kang 《Journal of Polymer Materials》 2025年第3期621-660,共40页
Due to their high water content,stimulus responsiveness,and biocompatibility,hydrogels,which are functional materials with a three-dimensional network structure,are widely applied in fields such as biomedicine,environ... Due to their high water content,stimulus responsiveness,and biocompatibility,hydrogels,which are functional materials with a three-dimensional network structure,are widely applied in fields such as biomedicine,environmental monitoring,and flexible electronics.This paper provides a systematic review of hydrogel charac-terization methods and their applications,focusing on primary evaluation techniques for physical properties(e.g.,mechanical strength,swelling behavior,and pore structure),chemical properties(e.g.,composition,crosslink density,and degradation behavior),biocompatibility,and functional properties(e.g.,drug release,environmental stimulus response,and conductivity).It analyzes the challenges currently faced by characterization methods,such as a lack of standardization,difficulties in dynamic monitoring,an insufficient micro-macro correlation,and poor adaptability to complex environments.It proposes solutions,such as a hierarchical standardization system,in situ imaging technology,cross-scale characterization,and biomimetic testing platforms.Looking ahead,hydrogel characterization techniques will evolve toward intelligent,real-time,multimodal coupling and standardized approaches.These techniques will provide superior technical support for precision medicine,environmental restoration,and flexible electronics.They will also offer systematic methodological guidance for the performance optimization and practical application of hydrogel materials. 展开更多
关键词 HYDROGEL characterization methods PROPERTIES standardIZATION APPLICATION
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The Impact of the Internationalization of ESG Standards on the Trade Competitiveness of Multinational Enterprises:A Difference-in-Differences Test Based on Global Manufacturing Listed Companies
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作者 Yihan Wang 《Proceedings of Business and Economic Studies》 2025年第4期239-244,共6页
This paper takes global manufacturing listed companies from 2010 to 2022 as samples and uses the difference-in-differences(DID)method to empirically examine the impact of the internationalization of ESG standards on t... This paper takes global manufacturing listed companies from 2010 to 2022 as samples and uses the difference-in-differences(DID)method to empirically examine the impact of the internationalization of ESG standards on the trade competitiveness of multinational enterprises and their mechanisms.The research finds that the internationalization of ESG standards significantly enhances the trade competitiveness of multinational manufacturing enterprises,and this effect is dynamic and sustainable.The mechanism analysis indicates that the internationalization of ESG standards exerts its influence through three pathways:reducing enterprise financing costs,promoting technological innovation,and enhancing brand reputation.The heterogeneity analysis shows that this effect is more significant in enterprises from developed countries,high-pollution industries,and larger enterprises.This paper provides micro-level evidence for understanding the economic consequences of the internationalization of ESG standards and offers policy implications for multinational enterprises to cope with the global ESG rule changes and enhance their trade competitiveness. 展开更多
关键词 Internationalization of ESG standards Trade competitiveness Multinational enterprises Difference-in-differences method Manufacturing industry Online publication:September 10 20251.Introduction
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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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Construction of type-Ⅱ QC-LDPC codes with fast encoding based on perfect cyclic difference sets 被引量:1
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作者 李玲香 李海兵 +1 位作者 李季碧 江华 《Optoelectronics Letters》 EI 2017年第5期358-362,共5页
In view of the problems that the encoding complexity of quasi-cyclic low-density parity-check(QC-LDPC) codes is high and the minimum distance is not large enough which leads to the degradation of the error-correction ... In view of the problems that the encoding complexity of quasi-cyclic low-density parity-check(QC-LDPC) codes is high and the minimum distance is not large enough which leads to the degradation of the error-correction performance, the new irregular type-Ⅱ QC-LDPC codes based on perfect cyclic difference sets(CDSs) are constructed. The parity check matrices of these type-Ⅱ QC-LDPC codes consist of the zero matrices with weight of 0, the circulant permutation matrices(CPMs) with weight of 1 and the circulant matrices with weight of 2(W2CMs). The introduction of W2CMs in parity check matrices makes it possible to achieve the larger minimum distance which can improve the error-correction performance of the codes. The Tanner graphs of these codes have no girth-4, thus they have the excellent decoding convergence characteristics. In addition, because the parity check matrices have the quasi-dual diagonal structure, the fast encoding algorithm can reduce the encoding complexity effectively. Simulation results show that the new type-Ⅱ QC-LDPC codes can achieve a more excellent error-correction performance and have no error floor phenomenon over the additive white Gaussian noise(AWGN) channel with sum-product algorithm(SPA) iterative decoding. 展开更多
关键词 Convolutional codes Encoding (symbols) Error correction Errors Gaussian noise (electronic) Iterative decoding Iterative methods Matrix algebra Satellite communication systems Set theory Signal encoding Turbo codes White noise
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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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Discussion on the Reform of Secure Coding
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作者 Yi Ma Dongming Chen Dongqi Wang 《计算机教育》 2022年第12期43-48,共6页
Secure Coding is an indispensable part of the undergraduate training program for Information Security Major.As a basic course for undergraduates to carry out project engineering,its importance is self-evident.In the a... Secure Coding is an indispensable part of the undergraduate training program for Information Security Major.As a basic course for undergraduates to carry out project engineering,its importance is self-evident.In the actual teaching activities,the program design courses have to be solved in terms of content update,practical ability improvement and scientific research project,so the curriculum reform is imperative.This paper analyses the main problems existing in the Secure Coding course,explores the solution,proposes teaching methods,and gives the evaluation method.The practice shows that the reform exploration can obtain good teaching results. 展开更多
关键词 Secure coding Case-based teaching method Modern teaching methods Evaluation methods
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Two-level Bregmanized method for image interpolation with graph regularized sparse coding 被引量:1
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作者 刘且根 张明辉 梁栋 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期384-388,共5页
A two-level Bregmanized method with graph regularized sparse coding (TBGSC) is presented for image interpolation. The outer-level Bregman iterative procedure enforces the observation data constraints, while the inne... A two-level Bregmanized method with graph regularized sparse coding (TBGSC) is presented for image interpolation. The outer-level Bregman iterative procedure enforces the observation data constraints, while the inner-level Bregmanized method devotes to dictionary updating and sparse represention of small overlapping image patches. The introduced constraint of graph regularized sparse coding can capture local image features effectively, and consequently enables accurate reconstruction from highly undersampled partial data. Furthermore, modified sparse coding and simple dictionary updating applied in the inner minimization make the proposed algorithm converge within a relatively small number of iterations. Experimental results demonstrate that the proposed algorithm can effectively reconstruct images and it outperforms the current state-of-the-art approaches in terms of visual comparisons and quantitative measures. 展开更多
关键词 image interpolation Bregman iterative method graph regularized sparse coding alternating direction method
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Effects of King’s Theory of Goal Attainment Combined with Teach-Back Method on Improving Patients’ Standardization Rate of Eye Drop Use
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作者 Qiuying Huang Guilian Jie Xiaohong Liu 《Journal of Clinical and Nursing Research》 2024年第12期22-27,共6页
Objective:To explore the effect of King’s Theory of Goal Attainment combined with teach-back method on improving the standardization rate of eye drop use in patients.Methods:A total of 200 patients who used more than... Objective:To explore the effect of King’s Theory of Goal Attainment combined with teach-back method on improving the standardization rate of eye drop use in patients.Methods:A total of 200 patients who used more than two types of eye drops in the Department of Ophthalmology of our hospital were selected as the research subjects,and were randomly divided into an observation group and a control group.The control group was given routine health education,while the observation group was given King’s Theory of Goal Attainment combined with teach-back method on the basis of the control group.The standardization rate of eye drop use,knowledge awareness rate,and nursing satisfaction were compared between the two groups before and after the intervention.Results:After the intervention,the standardization rate of eye drop use,the awareness rate of eye drop knowledge,and the nursing satisfaction of the observation group were significantly higher than those of the control group(P<0.05).Conclusion:King’s Theory of Goal Attainment combined with teach-back method can effectively improve the standardization rate of eye drop use in patients,increase their awareness of eye drop knowledge,and improve nursing satisfaction,which is worthy of clinical application. 展开更多
关键词 King’s Theory of Goal Attainment Teach-back method Eye drops standardization rate
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Study on the System of Aquatic Environmental Monitoring Methods in China 被引量:1
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作者 ZHANG Xiao-ling DENG Li SUN Jing 《Meteorological and Environmental Research》 CAS 2012年第3期53-56,共4页
The development of Chinese system of aquatic environmental monitoring methods was summarized. The existing problem of the system of aquatic environmental monitoring methods was analyzed. At last, some suggestions were... The development of Chinese system of aquatic environmental monitoring methods was summarized. The existing problem of the system of aquatic environmental monitoring methods was analyzed. At last, some suggestions were made on setting and implementing the system of aquat- ic environmental monitoring methods in China. 展开更多
关键词 Aquatic quality standards The system of aquatic environmental monitoring methods China
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A Mini Review on Testing Methods for Mechanical Properties of Natural Fibre Honeycomb Sandwich Structure and Fractography Analysis 被引量:1
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作者 Nahiyan Al-Azad Nur Hafidah Binti Dedifitrianto Mohd. Kamal Mohd. Shah 《Journal of Materials Science and Chemical Engineering》 2021年第5期29-38,共10页
This paper is a review of the past research of mechanical testing methods for natural fibre honeycomb sandwich structure as well as failure modes analysis at a microscopic level by using Scanning Electron Microscope (... This paper is a review of the past research of mechanical testing methods for natural fibre honeycomb sandwich structure as well as failure modes analysis at a microscopic level by using Scanning Electron Microscope (SEM). As the world is garnering attention towards renewable resources for environmental purposes, studies of natural fibre have been increasing as well as the application of natural fibre throughout various industries such as aerospace, automobiles, and construction sectors. This paper is started with brief information regarding the honeycomb sandwich structure, introduction to natural fibre, its applications as well as the factors affecting the performances of the structure. Next, the mechanical testing methods are listed out as well as the expected outcomes obtained from the respective testing. The mechanical properties are also identified by conducting lab tests according to the ASTM standard for sandwich and core structures. The microstructure of the deformed samples is then examined under Scanning Electron Microscope (SEM) by using different magnifications to study the failure mechanisms of the samples. The images obtained from the SEM test are analyzed by using fractography which will show the failure modes of the samples. This article is based on past research conducted by professional on the related topic. 展开更多
关键词 Natural Fibre Honeycomb Sandwich Structure Testing methods ASTM standard SEM Test
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The Mexican Environmental Flow Standard:Scope,Application and Implementation 被引量:2
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作者 Maria Antonieta Gomez-Balandra Maria del Pilar Saldana-Fabela Maricela Martinez-Jimenez 《Journal of Environmental Protection》 2014年第1期71-79,共9页
With the implementation of the Official Mexican Standard NOM-011-CONAGUA-2000 [1], the water balance of 730 basins has been calculated and its water availability agreement is published. This rule points out to allocat... With the implementation of the Official Mexican Standard NOM-011-CONAGUA-2000 [1], the water balance of 730 basins has been calculated and its water availability agreement is published. This rule points out to allocate water for the environment only as an annual volume since methods for estimating environmental flows were not standardized in the country. For this reason, The Water Agency (CONAGUA) issued the standard NMX-AA-159-SCFI-2012 [2], to assess environmental flows needed both, at the strategic level in Integrated Water Resources Management (IWRM), or as part of the Environmental Impact Assessment (EIA) of large hydraulic projects. For over ten years, this standard was developed and finally published in September 2012 [3]. It explains different methods from hydrological to holistic approaches, with examples for the country. Its application will cover the urgent need to preserve water for ecosystems in watersheds with high ecological importance and low stress for water use. In this paper, an analysis of the environmental flow standard and examples of the suggested hydrological methods are presented. For its implementation, some steps are taking place, mainly establishing environmental water reserves and building capacities. In addition, environmental allocations are becoming a common practice for all water projects, as well as setting limits to hydrological alterations by hydroelectric dams. The standard promotes the use of technical integration tools to analyze the responses of ecosystems to changes in the flow regime and adaptive management under different scenarios of water use. Although the main steps have been taken, its implementation as mandatory rule will take time. 展开更多
关键词 Environmental Flows Hydrological methods Mexican standard
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