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A review of the standardized measurement of the characteristics of graphene-based materials
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作者 Zhang Donghui Li Wan +2 位作者 Ou Bingxian Wang Liangwang Ge Guanglu 《新型炭材料(中英文)》 北大核心 2026年第1期91-108,共18页
Standardization is necessary for the early industrialization of the new materials and technology.It is achieved by having agreed practices for the measurement of properties and other characteristics.The promising use ... Standardization is necessary for the early industrialization of the new materials and technology.It is achieved by having agreed practices for the measurement of properties and other characteristics.The promising use of graphene-based materials in fields like electronics,energy,and composites has resulted in standards for their nomenclature,the measurement of key characteristics,and their specification,etc.Among these,standards for measuring the key characteristics are crucial.The critical parameters are the number of layers,the type and concentration of defects and functional groups,elemental composition,sheet resistance,and carrier mobility.Standards for characterizing these have been analyzed by the International Organization for Standardization Technical Committee in ISO/TC229 and the International Electrotechnical Commission Technical Committee in IEC/TC113.These give details of applicable or preferred samples,the fundamental principles of the techniques,specific precautions,and points for attention in the relevant standards.The pivotal role of the ISO/TC229 and IEC/TC113 standards is considered and challenges and future trends are outlined. 展开更多
关键词 Nanotechnology Graphene-based materials measurement standards Critical characteristics quality control
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China’s High-Quality Technology Innovation:Scenario Narrative and Measurement System
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作者 Chen Qiangyuan Zhao Haoyun +1 位作者 Lin Sitong Shen Yu 《China Economist》 2025年第1期2-28,共27页
The world today is undergoing disruptive,transformative shifts driven by a new wave of technological revolutions and industrial changes.In this context,a central question for China’s innovation-driven development str... The world today is undergoing disruptive,transformative shifts driven by a new wave of technological revolutions and industrial changes.In this context,a central question for China’s innovation-driven development strategy is how to effectively identify and measure high-quality technological innovations.Drawing on the stylized facts and scenario narrative of China’s technological landscape,this paper proposes a framework and measurement system for evaluating high-quality technological innovations.While China’s top-level design for technological innovation is guided by policy documents,the increasing number of enterprises applying for“high-tech enterprise”status has coincided with a decline in the quality of patent filings.In response,this paper first underscores the challenges and necessity of measuring the quality of technological innovations.Second,we introduce the high-quality technological innovation indicators and employ them to assess the quality of tech innovations at the firm level,utilizing an approach that combines analogical narrative,gene coding,text analysis,semantic logic,and a database of granted invention patents in China.Third,we examine the systematic and individual biases inherent in citation counts,a commonly used indicator,under specific contexts,and employ a granular instrumental variable approach to validate the effectiveness of the indicators.Finally,we develop a“family tree”of the indicators and explore their application scenarios through a combination of established and extended indicators.Our findings provide a theoretical foundation for evaluating China’s technological innovation quality,inform policy incentives,and offer insights for academia to apply high-quality technological innovation indicators in different contexts. 展开更多
关键词 Innovation quality technological innovation measurement system family tree
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Semi-supervised method for tunnel blasting quality prediction using measurement while drilling data
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作者 Hengxiang Jin Qian Fang +3 位作者 Jun Wang Jiayao Chen Gan Wang Guoli Zheng 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2633-2649,共17页
Predicting blasting quality during tunnel construction holds practical significance.In this study,a new semi-supervised learning method using convolutional variational autoencoder(CVAE)and deep neural network(DNN)is p... Predicting blasting quality during tunnel construction holds practical significance.In this study,a new semi-supervised learning method using convolutional variational autoencoder(CVAE)and deep neural network(DNN)is proposed for the prediction of blasting quality grades.Tunnel blasting quality can be measured by over/under excavation.The occurrence of over/under excavation is influenced by three factors:geological conditions,blasting parameters,and tunnel geometric dimensions.The proposed method reflects the geological conditions through measurements while drilling and utilizes blasting parameters,tunnel geometric dimensions,and tunnel depth as input variables to achieve tunnel blasting quality grades prediction.Furthermore,the model is optimized by considering the influence of surrounding rock mass features on the predicted positions.The results demonstrate that the proposed method outperforms other commonly used machine learning and deep learning algorithms in extracting over/under excavation feature information and achieving blasting quality prediction. 展开更多
关键词 Tunnel blasting quality Over/under excavation Semi-supervised learning measurement while drilling(MWD)
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Measurement and Spatio-temporal Distribution of Urbanization Development Quality of Urban Agglomeration in China 被引量:12
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作者 WANG Deli FANG Chuanglin +2 位作者 GAO Boyang HUANG Jinchuan YANG Qingshan 《Chinese Geographical Science》 SCIE CSCD 2011年第6期695-707,共13页
Urbanization development quality(UDQ) of urban agglomeration(UA) is one of the important indexes to evaluate if the UA urbanization speed is reasonable,if the population urbanization process is sound,if the economic u... Urbanization development quality(UDQ) of urban agglomeration(UA) is one of the important indexes to evaluate if the UA urbanization speed is reasonable,if the population urbanization process is sound,if the economic urbanization process is efficient,if the social urbanization process is harmonious and fair,which is generally composed of three parts,including economic urbanization development quality,social urbanization development quality and spa-tial urbanization security quality.With the research of evolution rules of UDQ,through the analysis on the interactive coordination relation between UDQ and urbanization level,the paper proposes three dimensional index ball and stan-dard value of comprehensive measures of UDQ,which is composed of three categories of indexes.By introducing At-kinson model,this paper constructs the sub-element measure model and segmental measure model of UDQ,and fur-ther makes an overall evaluation on the characteristic of UDQ of UAs in China.Results show that:1) UDQ of UAs lied at optimization and upgrading phase during 1995-2008 and the quality was low.Population urbanization level did not reflect the UDQ of UAs;2) the improving speed of the spatial urbanization security quality was higher than the so-cial urbanization development quality,and the improving speed of economic urbanization development quality was the lowest;3) the coordination between UDQ and urbanization level was not so good;4) there was a weak correlation re-lation between UDQ and UA scale,and it was not true that the bigger the UA was,the better the UDQ was. 展开更多
关键词 urbanization development quality (UDQ) urbanization speed comprehensive measure model urban ag-glomeration (UA)
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Quality control measures for lowering the seroconversion rate of hemodialysis patients with hepatitis B or C virus 被引量:7
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作者 Jing Yuan Yi Yang +4 位作者 Fei Han Ping Zhang Xiao-Ying Du Hua Jiang Jiang-Hua Chen 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2012年第3期302-306,共5页
BACKGROUND:Hemodialysis(HD)patients are at high risk of infection by hepatitis B virus(HBV)or hepatitis C virus(HCV).The present study was designed to determine the impact of quality control measures on the prevention... BACKGROUND:Hemodialysis(HD)patients are at high risk of infection by hepatitis B virus(HBV)or hepatitis C virus(HCV).The present study was designed to determine the impact of quality control measures on the prevention of transmission of blood-borne viruses.METHODS:A total of 6182 adult maintenance HD patients from all HD units in Zhejiang Province were recruited on January 1,2007.The baseline demographic and clinical characteristics were recorded and all patients were followed up until death or survival at 4 years later.The Quality Control Standards of Hemodialysis were gradually implemented in HD units.The HBV or HCV seroconversion rates of the recruited patients were calculated and compared every year during the observation period.RESULTS:The prevalence of HBV was 8.3%at the beginning of the study,and 6.6%for HCV.With the implementation of the HD quality control measures,the HBV seroconversion rate tended to decrease year by year(χ2=6.620,P=0.085),and the HCV seroconversion rate decreased significantly(χ2=10.41,P=0.015).Compared with the data in 2007,the HBV seroconversion rate(χ2=4.204,P=0.040,relative risk ratio 0.393,95%CI 0.156-0.991)and the HCV seroconversion rate(χ2=7.373,P=0.007,relative risk ratio 0.386,95%CI 0.189-0.787)decreased significantly in 2010.CONCLUSION:Quality control measures for HD decreased the seroconversion rates of HBV or HCV in HD patients,showing that updated quality control measures reduce the risk for transmission of blood-borne viruses in the HD population. 展开更多
关键词 HEMODIALYSIS quality control measures INFECTION hepatitis B virus hepatitis C virus
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Constraints of Quality and Marketing of Gannan Navel Orange and Measures for Industrial Development 被引量:2
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作者 Yayan CHEN 《Asian Agricultural Research》 2017年第4期20-25,共6页
In order to provide reference for the sustainable development of Gannan navel orange industry,this paper analyzed constraints of quality and marketing of Gannan navel orange. From developing the dominant area of the n... In order to provide reference for the sustainable development of Gannan navel orange industry,this paper analyzed constraints of quality and marketing of Gannan navel orange. From developing the dominant area of the navel orange and ensuring high quality healthy development of navel orange,it came up with sustainable development recommendations for Gannan navel orange industry,to realize high quality,efficient,and deep development of Gannan navel orange industry in both the area and quantity,and change from simple planting and sales to fresh fruit sales,deep processing,and tourism combined development. 展开更多
关键词 Gannan navel orange quality MARKETING CONSTRAINTS measures
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An integrated measurement and modeling methodology for estuarine water quality management 被引量:1
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作者 Michael Hartnett Stephen Nash 《Water Science and Engineering》 EI CAS CSCD 2015年第1期9-19,共11页
This paper describes research undertaken by the authors to develop an integrated measurement and modeling methodology for water quality management of estuaries. The approach developed utilizes modeling and measurement... This paper describes research undertaken by the authors to develop an integrated measurement and modeling methodology for water quality management of estuaries. The approach developed utilizes modeling and measurement results in a synergistic manner. Modeling results were initially used to inform the field campaign of appropriate sampling locations and times, and field data were used to develop accurate models. Remote sensing techniques were used to capture data for both model development and model validation. Field surveys were undertaken to provide model initial conditions through data assimilation and determine nutrient fluxes into the model domain. From field data, salinity re- lationships were developed with various water quality parameters, and relationships between chlorophyll a concentrations, transparency, and light attenuation were also developed. These relationships proved to be invaluable in model development, particularly in modeling the growth and decay of chlorophyll a. Cork Harbour, an estuary that regularly experiences summer algal blooms due to anthropogenic sources of nutrients, was used as a case study to develop the methodology. The integration of remote sensing, conventional fieldwork, and modeling is one of the novel aspects of this research and the approach developed has widespread applicability. 展开更多
关键词 Estuarine modeling HYDRODYNAMICS Water quality management NUTRIENTS PHYTOPLANKTON Field measurements Remote sensing
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Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements
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作者 Peng Li Meifeng Cai +2 位作者 Shengjun Miao Yuan Li Yu Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期39-48,共10页
Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stre... Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution method.The results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with depth.There is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and messy.Moreover,there is no obvious relationship between the rock quality designation(RQD)and depth.The maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same depth.In addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data. 展开更多
关键词 overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification
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A systematic review: How to choose appropriate health-related quality of life (HRQOL) measures in routine general practice? 被引量:2
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作者 陈天辉 李鲁 KOCHEN Michael M 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第9期936-940,共5页
In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must... In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must not only be valid, appro- priate, reliable, responsive, and capable of being interpreted, but it must also be simple, fast to complete, easy to score, and provide useful clinical data. The Two-step method of choosing appropriate measures is introduced. Then through comparison of generic instruments with disease-specific instruments, we can conclude that sometimes a combination of generic and disease-specific HRQOL measures may be more appropriate for monitoring changes in a patient’s health status due to an intervention. 展开更多
关键词 Health-related quality of life (HRQOL) GENERIC Disease-specific measure General practice
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Repeatability of in-vitro optical quality measurements of intraocular lenses with a deflectometry technique effect of the toricity 被引量:1
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作者 Teresa Ferrer-Blasco Alberto Dominguez-Vicent +3 位作者 Santiago Garcia-Lazaro Maria Amparo Diez-Ajenjo Jose F.Alfonso Jose J.Esteve-Taboada 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第7期1139-1144,共6页
AIM: To evaluate the repeatability of an optical device for measuring the Zernike coefficients of toric intraocular lenses(IOLs) and assess whether its toricity has any impact in its repeatability. METHODS: An exp... AIM: To evaluate the repeatability of an optical device for measuring the Zernike coefficients of toric intraocular lenses(IOLs) and assess whether its toricity has any impact in its repeatability. METHODS: An experienced technician used the NIMO TR1504 to measure the Zernike coefficients 30 times for an aperture of 4.50 mm for all lenses included. The IOLs included were divided into two group: toric and nontoric ones. The cylindrical powers of the toric lenses included in the present study were 1.00, 1.50, 2.25, 3.00 and 3.75 D. Finally, the repeatability of the NIMO TR1504 was described in terms of within subject standard deviation(Sw) and repeatability limit. RESULTS: The Sw was smaller than 0.011 μm for both lens groups and all Zernike coefficients, and the difference between both groups was smaller than 0.004 μm for all Zernike coefficients. Regarding the repeatability limit, this value was smaller than 0.025 μm for the toric lens group, and smaller than 0.031 μm for the non-toric lens one for all Zernike coefficients. Furthermore, the maximum difference between both lens groups was 0.010 μm. CONCLUSION: The repeatability of the NIMO TR1504 to measure the optical quality is high and independent of the lens toricity. These results reflect that this system is robust and could be used to measure the in-vitro optical quality of either toric or non-toric IOLs. 展开更多
关键词 in-vitro measurements optical quality intraocular lens REPEATABILITY
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Measurement of the cavity-loaded quality factor in superconducting radio-frequency systems with mismatched source impedance 被引量:2
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作者 Jin-Ying Ma Cheng-Ye Xu +12 位作者 An-Dong Wu Guo-Dong Jiang Yue Tao Zong-Heng Xue Long-Bo Shi Tian-Cai Jiang Zheng-Long Zhu Zi-Qin Yang Zheng Gao Lie-Peng Sun Gui-Rong Huang Feng Qiu Yuan He 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第8期12-23,共12页
The accurate measurement of parameters such as the cavity-loaded quality factor(Q_(L))and half bandwidth(f_(0.5))is essential for monitoring the performance of superconducting radio-frequency cavities.However,the conv... The accurate measurement of parameters such as the cavity-loaded quality factor(Q_(L))and half bandwidth(f_(0.5))is essential for monitoring the performance of superconducting radio-frequency cavities.However,the conventional"field decay method"employed to calibrate these values requires the cavity to satisfy a"zero-input"condition.This can be challenging when the source impedance is mismatched and produce nonzero forward signals(V_(f))that significantly affect the measurement accuracy.To address this limitation,we developed a modified version of the"field decay method"based on the cavity differential equation.The proposed approach enables the precise calibration of f_(0.5) even under mismatch conditions.We tested the proposed approach on the SRF cavities of the Chinese Accelerator-Driven System Front-End Demo Superconducting Linac and compared the results with those obtained from a network analyzer.The two sets of results were consistent,indicating the usefulness of the proposed approach. 展开更多
关键词 Loaded quality factor Field decay method Superconducting cavity MISMATCH Calibration Cavity differential equation measurement Accelerator-driven system
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Discussion on the Measurement Method for the Coda Wave Quality Factor 被引量:1
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作者 Liu Xiqiang Shi Yuyan Qu Junhao Li Hong Li Bo Zhang Kun 《Earthquake Research in China》 2009年第4期420-433,共14页
The Quality factor is the parameter that can be used to describe the energy attenuation on seismic wave. In theory, we can obtain the relationship between the change of the coda wave quality factor with time and the s... The Quality factor is the parameter that can be used to describe the energy attenuation on seismic wave. In theory, we can obtain the relationship between the change of the coda wave quality factor with time and the strong earthquake preparation process on the basis of the quality factor of a coda wave in a same ray path. However, in reality the coda wave quality factor measured by different seismic coda waves corresponds to different seismic wave ray paths. The change of the quality factor with time is related to non-elastic characteristics of the medium and the volume of scattering ellipsoid constrained by scattered wave phase fronts, besides the change of regional stress field. This paper discusses the relationship between quality factor, epicenter distance and different lapse time, and then discusses the relationship between quality factor and frequency. Furthermore the determination method of the coda wave quality factor is put forward. The improved determination method of the quality factor, which removes the influence of different earthquakes or propagation depth of scattered waves, may increase measurement precision, thus information pertaining to abnormal changes in quality factor and the relationship between the quality factor and earthquake preparation process can be acquired. 展开更多
关键词 quality factor Coda wave measurement method DISCUSSION APPLICATION
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THE DISCUSSION ON THE MEASURES OF INCREASING NURSERY STOCK QUALITY IN FRIGID REGION OF CHINA
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作者 Qi Mingcong Shen Hailong Northeast Forestry University Yang Xiujuan Museum of Heilongjiang Province 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1993年第2期43-50,共8页
Through several years seedling-growing experiments in nursery in Daxing‘anMountains forest region,the author posed that the seedling cultivated for the region mustpossess the characteristics of being suited to thin a... Through several years seedling-growing experiments in nursery in Daxing‘anMountains forest region,the author posed that the seedling cultivated for the region mustpossess the characteristics of being suited to thin and meager soil and having strongresistance to adverse conditions.For this purpose,the cultivation regime ought to bedirectization,standardization and programmatization;seedling growth ought to be promotedby regulating ecological conditions;and the mursery stock quality ought to be tested usingvigor index. 展开更多
关键词 Seedling-growing measure Frigid REGION NURSERY STOCK quality
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Dialysis Symptom Index:Patient-reported outcome measures study of dialysis patients in low resource settings in India
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作者 Anuradha Pichumani Pichumani Kodaganallur Parthasarathi +5 位作者 Nagarajan Mani Sriram Damal Kandadai Deepalaxmi Rathakrishnan Murali Krishna Moka Latha Sundar Melvin George 《World Journal of Nephrology》 2025年第4期221-232,共12页
BACKGROUND End-stage renal disease is the final stage of chronic kidney disease,with hemodialysis as the primary treatment in India.Despite its prevalence,limited studies have focused on patient-reported outcomes,such... BACKGROUND End-stage renal disease is the final stage of chronic kidney disease,with hemodialysis as the primary treatment in India.Despite its prevalence,limited studies have focused on patient-reported outcomes,such as symptom burden and healthrelated quality of life.AIM To evaluate the symptom burden among adult hemodialysis patients and identify factors influencing their outcomes.METHODS A multi-center,cross-sectional study was conducted among 157 adult hemodialysis patients in Chennai from March 2024 to June 2024.The Dialysis Symptom Index tool was used to assess 30 physical and emotional symptoms.Correlations between symptom severity and clinical parameters,such as hemoglobin levels and urea reduction ratio(URR),were analyzed.RESULTS Moderate symptoms were reported by 48%of participants,with worry,insomnia,and feeling unwell identified as the most severe.Psychological symptoms significantly correlated with lower hemoglobin levels,while shortness of breath was linked to suboptimal URR values.Approximately 38%of patients had URR<65%,which was associated with increased symptom burden.CONCLUSION Hemodialysis patients experience a substantial psychological and sleep-related symptom burden,emphasizing the need for dialysis adequacy and better hemoglobin management.Enhanced strategies addressing these factors could significantly improve patient outcomes. 展开更多
关键词 Chronic kidney disease HEMODIALYSIS Dialysis Symptom Index Patient-reported outcome measures Symptom burden quality of life
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A Measurement Study of Economic Growth Transition Based on Quality Index: A Case of Economic Growth in Shenzhen
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作者 XIANG Shu-jian ZHENG Rui-kun 《当代财经》 CSSCI 北大核心 2013年第S1期80-93,共14页
How to realize the transition of China’s economic growth from"speed type"to"quality type"is a problem full of exploratory contents;scholars give it wide attention from different theoretical perspe... How to realize the transition of China’s economic growth from"speed type"to"quality type"is a problem full of exploratory contents;scholars give it wide attention from different theoretical perspectives.And it is an indispensable part of the theoretical research to design an index to measure the transition process from speed to quality from the quantitative angle,so as to visually reflect the degree of transition of economic growth.By drawing on the economic principles and design ideas of the market index,this paper designs the quality index as the quantitative indicator to measure the transition of economic growth model,and quantitatively measures the degree of realization from"Shenzhen speed"to"Shenzhen quality".The results of the empirical evaluation indicate that"Shenzhen speed"has begun to transit to"Shenzhen quality",but the improvement of people’s living standards falls behind substantially the level of economic development of Shenzhen.Regarding this as an opportunity,this paper provides an analytical idea for a quantitative measurement of the economic growth transition in China. 展开更多
关键词 ECONOMIC growth TRANSITION quality index QUANTITATIVE measureMENT
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Use of signal quality measurements to gain efficiency in the analysis of cDNA microarray data
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作者 Tracy L Bergemann 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2010年第4期265-279,共15页
This research provides a new way to measure error in microarray data in order to improve gene expression analysis. Microarray data contains many sources of error. In order to glean information about mRNA expression le... This research provides a new way to measure error in microarray data in order to improve gene expression analysis. Microarray data contains many sources of error. In order to glean information about mRNA expression levels, the true signal must first be segregated from noise. This research focuses on the variation that can be captured at the spot level in cDNA microarray images. Variation at other levels, due to differences at the array, dye, and block levels, can be corrected for by a variety of existing normalization procedures. Two signal quality estimates that capture the reliability of each spot printed on a microarray are described. A parametric estimate of within-spot vari ance, referred to here as σ^2spot, assumes that pixels follow a normal distribution and are spatially correlated. A non-parametric estimate of error, called the mean square prediction error (MSPE), assumes that spots of high quality possess pixels that are similar to their neighbors. This paper will provide a framework to use either spot quality measure in downstream analysis, specifically as weights in regression models. Using these spot quality estimates as weights can result in greater efficiency, in a statistical sense, when modeling mi- croarray data. 展开更多
关键词 microarrays signal quality PREDICTION measurement error models
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OBJECTIVE IMAGE QUALITY MEASURES AND THEIR APPLICATIONS IN SEGMENTATION EVALUATION
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作者 Zhang Yujin (Department pf Electronic Engineering, Tsinghua University, 100084 Beijing) 《Journal of Electronics(China)》 1997年第2期97-103,共7页
Image segmentation is a critical step of image analysis. Segmentation evaluation is an effective procedure for studying the performance of segmentation techniques, in which quality measure plays an important role. Thi... Image segmentation is a critical step of image analysis. Segmentation evaluation is an effective procedure for studying the performance of segmentation techniques, in which quality measure plays an important role. This paper presents a group of new objective quality measures for segmentation evaluation and compares their performances. In addition, to verify the effectiveness of these new measures, an appropriate classification of segmentation is proposed. According to this classification, several representative algorithms from different categories are selected for comparison testing. Some valuable results are obtained and presented. 展开更多
关键词 IMAGE SEGMENTATION SEGMENTATION evaluation IMAGE quality measures ALGORITHM CLASSIFICATION
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Compliance of Milk Quality and Safety Measures Among Milk Producers and Milk Collection Centers in South Region of Punjab Province,Pakistan
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作者 Mazhir Nadeem Ishaq Li Cui-xia +2 位作者 Rukhsana Rasheed Majid Lateef Muhammad Abdullah 《Journal of Northeast Agricultural University(English Edition)》 CAS 2017年第1期80-91,共12页
The present study was conducted in four districts of Punjab Province to examine the attitude of milk producers and milk collection agents toward compliance of milk quality and safety parameters. In current scenario, t... The present study was conducted in four districts of Punjab Province to examine the attitude of milk producers and milk collection agents toward compliance of milk quality and safety parameters. In current scenario, the attitude of consumers for safe food in accordance to quality standards is ever increasing. The dairy industry in Pakistan is confronting many challenges to adapt these food safety and quality measures. This study was purposely conducted in the south region of Punjab Province, as this region has rich population of livestock and milk production. To collect essential data, field study was carded out in selected four districts of Punjab Province. Field survey for dairy farmers and milk collection centers was performed in two phases. The analysis of primary data was carried out by calculating the Likert scale mean value, analysis of variance (one-way) and other descriptive statistics tools. The results showed that 76.4% milk producers had no awareness about Punjab food quality laws; as Likert-scale mean value was 1.93. The compliance level for the management practices such as Hazard Analysis of Critical Control Point (HCCAP), Good Animal Practices (GAP) and Good Veterinary Practices (GVP) etc. was also very poor. Approximately, 32.57% milk collectors (very frequently) applied milk quality testing parameters whereas 50.72% milk collectors merely used sensory quality inspection methods at the time of milk purchase from dairy farmers. For a sustainable supply of good quality raw milk to the dairy industry in Pakistan, it was recommended that the departments for hygiene and food inspection should be vigilant. The prescribed food safety laws relating to milk production and marketing activities should be enforced properly to improve the situation. 展开更多
关键词 dairy farmer milk collection center milk quality standard food safety measure PUNJAB
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Techniques trend analysis of propagating laser beam quality measurement
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作者 刘伟平 Igor Lyuboshenko 《Journal of Measurement Science and Instrumentation》 CAS 2013年第1期83-88,共6页
Different methods of measuring a propagating laser beam quality are summarized.The disadvantages in traditional way in measuring a laser beam quality is analyzed and the insufficiencies of the Shack-Hartmannin method ... Different methods of measuring a propagating laser beam quality are summarized.The disadvantages in traditional way in measuring a laser beam quality is analyzed and the insufficiencies of the Shack-Hartmannin method which is commonly using wave front technique at present is pointed out.Finally,the transmission intensity equation based(TIE-based)measuring way in a laser beam quality evaluation and the corresponding advantages are discussed,which is believed to be a deve-l oping trend in laser beam evaluation. 展开更多
关键词 laser beam quality measureMENT wave FRONT technique M2 factor transmission INTENSITY equation(TIE)
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Non-Intrusive Objective Speech Quality Measurement Based on Fuzzy GMM and SVR for Narrowband Speech
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作者 王晶 张莹 +1 位作者 赵胜辉 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2010年第1期76-81,共6页
Based on fuzzy Gaussian mixture model (FGMM) and support vector regression (SVR),an improved version of non-intrusive objective measurement for assessing quality of output speech without inputting clean speech is ... Based on fuzzy Gaussian mixture model (FGMM) and support vector regression (SVR),an improved version of non-intrusive objective measurement for assessing quality of output speech without inputting clean speech is proposed for narrowband speech.Its perceptual linear predictive (PLP) features extracted from clean speech and clustered by FGMM are used as an artificial reference model.Input speech is separated into three classes,for each a consistency parameter between each feature pair from test speech signals and its counterpart in the pre-trained FGMM reference model is calculated and mapped to an objective speech quality score using SVR method.The correlation degree between subjective mean opinion score (MOS) and objective MOS is analyzed.Experimental results show that the proposed method offers an effective technique and can give better performances than the ITU-T P.563 method under most of the test conditions for narrowband speech. 展开更多
关键词 non-intrusive measurement objective speech quality fuzzy Gaussian mixture model (FGMM) support vector regression (SVR)
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