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Factor Structure and Measurement Invariance of the Japanese Version of the Mother-to-Infant Bonding Scale
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作者 Mami Yamamoto Fumie Takauma +2 位作者 Katsuhiko Tada Kaori Baba Toshinori Kitamura 《Advances in Reproductive Sciences》 2023年第4期159-170,共12页
Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeat... Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeated use of a questionnaire has problems of reduced validity. In order to correctly detect bonding disorders at multiple time points, it is necessary to confirm the measurement invariance of the scale. Baba et al. reported that invariance of the MIBS-J factor structure could only be obtained by abridging the scale into three items. Purpose: The aim of this study was to 1) confirm the factor structure and measurement invariance of the MIBS-J between two measurement times and 2) to examine factors that can be used without being affected by measurement time in order to identify item that contribute to measure met invariance. Methods: We analysed the data of 1049 and 878 mothers with a neonate collected in two waves: 5 days (Wave 1) and 1 month postpartum (Wave 2). Exploratory and confirmatory factor analyses were conducted on the data randomly divided into two groups in each wave. Results: The three-item model (MIBS-J items 1, 6, and 8) was most accepted. Measurement invariance and structural invariance were confirmed in the model. This was consistent with Baba et al.’s model. Conclusion: The three MIBS-J items showed measurement invariance and structural invariance in Japanese mothers during 1 month postpartum. 展开更多
关键词 Bonding Disorders Mother-to-Infant Bonding scale Factor Analysis measurement Invariance
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对“measurement scale”的译名、应用分析
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作者 隗金水 章岚 《山东体育学院学报》 北大核心 2005年第6期57-60,共4页
主要以文献资料法对“measurement sscale”一词进行了详细的考察,主要内容包括measurement scale的译文、定义、分类、特点、统计适用及其在调查问卷中的应用问题等,为了区分心理学、教育学和社会学中常用的“量表”一词,建议在《体育... 主要以文献资料法对“measurement sscale”一词进行了详细的考察,主要内容包括measurement scale的译文、定义、分类、特点、统计适用及其在调查问卷中的应用问题等,为了区分心理学、教育学和社会学中常用的“量表”一词,建议在《体育测量评价》教材中把“measurement scale”改译为“测量尺度”则更为合适。研究旨在丰富《体育测量评价》教材内容的同时,为measurement scale在统计科研中的准确运用提供参考。 展开更多
关键词 测量尺度 定类尺度 定序尺度 定距尺度 定比尺度
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Research on Analytical Method of Fatigue Characteristics of Soft Yoke Mooring System Based on Full-Scale Measurement 被引量:3
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作者 WU Wen-hua LV Bai-cheng +2 位作者 YUE Qian-jin ZHANG Yan-tao LIN Yang 《China Ocean Engineering》 SCIE EI CSCD 2017年第2期230-237,共8页
By focusing on the vulnerability of the structure of marine equipments, together with considering the randomness of meta-ocean load in statistics, a kind of analytical method of fatigue characteristics of marine struc... By focusing on the vulnerability of the structure of marine equipments, together with considering the randomness of meta-ocean load in statistics, a kind of analytical method of fatigue characteristics of marine structure based on full- scale and actual measurement of prototype is proposed. On the basis of short-term field measurement results of structural response, research is carried out on the fatigue analysis of hinge joints at the upper part of the Soft Yoke single point Mooring System (SYMS) by simultaneously monitoring the environmental load and considering the design criteria of offshore structure. Through analysis of finite element modeling, the time-histories of typical stress response are obtained, and then the assessment of fatigue damage at key hinge joints is conducted. The simulation results indicate that the proposed method can accurately analyze the fatigue damage of offshore engineering structure caused by the effect of wave load. The present analytical method of fatigue characteristics can be extended on other offshore engineering structures subjected to meta-ocean load. 展开更多
关键词 fatigue characteristics full scale measurement finite element method SYMS
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Measurement invariance and latent mean differences of the Chinese version physical activity self-efficacy scale across gender and education levels 被引量:1
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作者 Han Chen Jun Dai Yong Gao 《Journal of Sport and Health Science》 SCIE 2019年第1期46-54,共9页
Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has... Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has rarely been conducted in China. The current study aims to examine(1) the unidimensionality of a shortened Chinese version of PA self-efficacy scale(S-PASESC);(2) the measurement invariance of S-PASESC across gender and levels of education;(3) the latent factor mean difference between gender and levels of education;(4) the direct effects of self-efficacy on PA by different gender and education levels; and(5) the comparisons of the direct effects of self-efficacy on PA across gender and education levels.Methods: The participants were 5 th through 11 th grade public school students recruited from 7 cities located in different geographic regions of China. The final data include a total of 3003 participants(49.7% boys) who have completed the scales.Results: Confirmatory factor analysis(CFA) test supported the unidimensionality of S-PASESC. The S-PASESC is invariant across gender and 3 levels of education at both configural, full metric, and full scalar levels. Findings from latent mean comparisons showed that boys reported higher PA self-efficacy than girls. Students' perceived PA self-efficacy tend to decrease from elementary to high school. Finally, self-efficacy positively related to PA by groups of different gender and education levels and the relationship between self-efficacy and PA is stronger among middle school boys than girls.Conclusion: Findings suggest S-PASESC is a valid scale for measuring Chinese students' PA self-efficacy. 展开更多
关键词 Chinese adolescents Education levels Factor analysis GENDER LATENT mean comparison measurement INVARIANCE Physical activity SELF-EFFICACY scale
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Videometric research on deformation measurement of large-scale wind turbine blades 被引量:5
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作者 Xiangyi Sun,Yun Yuan,~(a))Zhaokun Zhu,Xiaohu Zhang,and Qifeng Yu College of Aerospace and Materials Engineering,National University of Defense Technology,Changsha 410073, Hunan,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第1期22-24,共3页
Utilization of wind energy is a promising way to generate power,and wind turbine blades play a key role in collecting the wind energy effectively.This paper attempts to measure the deformation parameter of wind turbin... Utilization of wind energy is a promising way to generate power,and wind turbine blades play a key role in collecting the wind energy effectively.This paper attempts to measure the deformation parameter of wind turbine blades in mechanics experiments using a videometric method. In view that the blades experience small buckling deformation and large integral deformation simultaneously, we proposed a parallel network measurement(PNM) method including the key techniques such as camera network construction,camera calibration,distortion correction,the semi-automatic high-precision extraction of targets,coordinate systems unification,and bundle adjustment,etc. The relatively convenient construction method of the measuring system can provide an abundant measuring content,a wide measuring range and post processing.The experimental results show that the accuracy of the integral deformation measurement is higher than 0.5 mm and that of the buckling deformation measurement higher than 0.1mm. 展开更多
关键词 VIDEOMETRICS deformation measurement wind turbine blades LARGE-scale integral deformation buckling deformation
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Scaled radar cross section measurement method for lossy targets via dynamically matching reflection coefficients in THz band
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作者 Shuang Pang Yang Zeng +2 位作者 Qi Yang Bin Deng Hong-Qiang Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期759-764,共6页
In the terahertz band,the dispersive characteristic of dielectric material is one of the major problems in the scaled radar cross section(RCS)measurement,which is inconsistent with the electrodynamics similitude deduc... In the terahertz band,the dispersive characteristic of dielectric material is one of the major problems in the scaled radar cross section(RCS)measurement,which is inconsistent with the electrodynamics similitude deducted according to the Maxwell’s equations.Based on the high-frequency estimation method of physical optics(PO),a scaled RCS measurement method for lossy objects is proposed through dynamically matching the reflection coefficients according to the distribution of the object facets.Simulations of the model of SLICY are conducted,and the inversed RCS of the lossy prototype is obtained using the proposed method.Comparing the inversed RCS with the calculated results,the validity of the proposed method is demonstrated.The proposed method provides an effective solution to the scaled RCS measurement for lossy objects in the THz band. 展开更多
关键词 scaled measurement method radar cross section lossy targets TERAHERTZ
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A Study of Precision Factors of Large-scale Object Surface Profile Laser Scanning Measurement
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作者 WANG Long-shan 1, LI De-long 2, NIE Meng-yu 3, ZHENG Z hong-wei 1 (1. The Science of Mechanical and Engineering College of Ji lin University, Changchun 130025, China 2. The Factory Automation Deparment of Shanghai Marine Equipment Research Institute, Shanghai 200031,China 3. Changchun Lat Exhaust Systems Company Ltd., Changchun 130022, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期162-,共1页
In this paper, we presented a method of using the l as er scanning triangulation for the non-contact 3D surface profile measurement of large-scale object. The characteristic of large-scale object non-contact mea surem... In this paper, we presented a method of using the l as er scanning triangulation for the non-contact 3D surface profile measurement of large-scale object. The characteristic of large-scale object non-contact mea surement is analyzed and the measuring method is proposed. Main factors influenc ing measurement precision such as image distortion and accurate designation of s peckle center are analyzed and methods of solving these problems are proposed. W e designed a combined filter by which the pulse noise and the Gaussian noise of speckle image can be eliminated efficiently. Using the characteristic of intensi ty distribution of laser speckle image we proposed a new approximating method th at could locate the center of laser speckle image at sub-pixel. The auxiliary v ariables are set to linearize the relationship between the image displacement an d the distance, the accurate values of laser triangulation system parameters cou ld be calibrated accurately and the measuring precision is increased remarkabl y. Using the above techniques we designed a measuring system based on laser sc anning triangulation. The results of the experiment show that these methods can raise the measuring precision of large-scale 3D surface profile effectively. 展开更多
关键词 large-scale object laser scanning precision fa ctors 3D measurement
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Numerical simulation and parameter optimization of Coriolis force scale measurement process based on DEM
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作者 Haiting Liu Yong Yang +2 位作者 Xiangliang Wang Jiewen Deng Bingbing Wang 《Particuology》 SCIE EI CAS CSCD 2024年第7期128-139,共12页
The Coriolis force method is a recently developed and highly regarded direct measurement technique that enables high-precision measurement of bulk materials.The operational parameters and variations thereof directly i... The Coriolis force method is a recently developed and highly regarded direct measurement technique that enables high-precision measurement of bulk materials.The operational parameters and variations thereof directly influence the measurement accuracy of the equipment.In this study,a measurement correction coefficient is introduced to improve the calculation method for mass flow rate of the materials.The DEM is employed to simulate the motion of particle groups within the Coriolis force scale under different parameters,and the effects of various structural and operational parameters on the measurement results are compared.The research findings indicate that a lower rotational speed leads to more stable instantaneous measurement results,although the measurement error is relatively large.When the rotational speed exceeds 300 rpm,the measurement error remains within 15%.For materials with a radius of 1–2 mm,the variation range of precision error is approximately 0.4%.Among the structural parameters,the radius of the measurement wheel has the most significant impact on the measurement results,wherein a larger measurement wheel radius corresponds to a smaller measurement error.The horizontal angle of the blades follows as the next influential parameter,with a clockwise rotation and a horizontal angle of 30°resulting in a measurement error below 2%. 展开更多
关键词 Parameter optimization Discrete element method Coriolis force scale measurement error Numerical simulation
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Novel Method for Spatial Angle Measurement Based on Rotating Planar Laser Beams 被引量:18
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作者 YANG Linghui YANG Xueyou ZHU Jigui DUAN Muqiong LAO Dabao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第6期758-764,共7页
Spatial angle measurement, especially the measurement of horizontal and vertical angle, is a basic method used for industrial large-scale coordinate measurement. As main equipments in use, both theodolites and laser t... Spatial angle measurement, especially the measurement of horizontal and vertical angle, is a basic method used for industrial large-scale coordinate measurement. As main equipments in use, both theodolites and laser trackers can provide very high accuracy for spatial angle measurement. However, their industrial applications are limited by low level of automation and poor parallelism. For the purpose of improving measurement efficiency, a lot of studies have been conducted and several alternative methods have been proposed. Unfortunately, all these means are either low precision or too expensive. In this paper, a novel method of spatial angle measurement based on two rotating planar laser beams is proposed and demonstrated. Photoelectric receivers placed on measured points are used to receive the rotating planner laser signals transmitted by laser transmitters. The scanning time intervals of laser planes were measured, and then measured point's horizontal/vertical angles can be calculated. Laser plane's angle parameters are utilized to establish the abstract geometric model of transmitter. Calculating formulas of receiver's horizontal/vertical angles have been derived. Measurement equations' solvability conditions and judgment method of imaginary solutions are also presented after analyzing. Proposed method for spatial angle measurement is experimentally verified through a platform consisting of one laser transmitter and one optical receiver. The transmitters used in new method are only responsible for providing rotating light plane signals carrying angle information. Receivers automatically measure scanning time of laser planes and upload data to the workstation to calculate horizontal angle and vertical angle. Simultaneous measurement of multiple receivers can be realized since there is no human intervention in measurement process .Spatial angle measurement result indicates that the repeatable accuracy of new method is better than 10". Proposed method can improve measurement's automation degree and speed while ensuring measurement accuracy. 展开更多
关键词 large-scale coordinate measurement spatial angle measurement rotating planar laser beams measurement automation
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Global exponentially stability for time-delay and time-varying measure large scale systems with impulsive effects
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作者 刘云龙 高存臣 +1 位作者 李云艳 刘现明 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期175-180,共6页
The global exponentially stability was studied for time-delay and time-varying measure large scale systems with impulsive effects. Firstly, the concepts are drawn for the functional category. Secondly, some sufficient... The global exponentially stability was studied for time-delay and time-varying measure large scale systems with impulsive effects. Firstly, the concepts are drawn for the functional category. Secondly, some sufficient conditions of the uniformly stability and the global exponentially stability are given for the above systems through defining a Lyapunov function of the weighting sum of the variable absolute by using the Lyapunov function method and the comparison principle. At the same time, the new conclusion of stability of these systems is more universal and contains the existing results. Finally, an example is given to illustrate the feasibility and validity of the obtained results. 展开更多
关键词 distributional DERIVATIVE TIME-DELAY measurE large scale systems IMPULSIVE GLOBAL EXPONENTIALLY stability
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Analysis of Heat Environment Indexes Using Integrated Remote Sensing and Site Measurement Techniques in a Community
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作者 Kun Li Jian Kang +1 位作者 Ye-Hao Song Dong Jiang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第5期1-9,共9页
Remote sensing and on-site measurement are used to determine the heat environment within a community,and are compared the differences for heat analysis. The two methods perform differently for various underlying surfa... Remote sensing and on-site measurement are used to determine the heat environment within a community,and are compared the differences for heat analysis. The two methods perform differently for various underlying surfaces. The individual methods can detect different aspects of the heat environment,which used in combination are useful for heat island research. The differences in estimated air and surface temperatures are smaller in open space and more obvious for vegetated surfaces. Ventilation does not affect the difference between air and surface temperature in open areas,and the vegetation surface and shading moderates surface temperature more effectively than the water surface; The forest is a type of underlying surface with heat comfortable,in which the feeling of air temperature is much difference to the structure of heat environment that should be survey and detected separately. The two methods can be used to study different aspects of the heat environment,thus forming a comprehensive approach for planners in urban and rural spaces. 展开更多
关键词 heat environment remote sensing site measurement community scale
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Measurement invariance of maternal ratings of ADHD symptoms across clinic referred children’s with and without ADHD
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作者 Rapson Gomez Alasdair Vance Vasileios Stavropoulos 《Advances in Developmental and Educational Psychology》 2019年第1期7-17,共11页
The study examined the measurement invariance (configural,metric,scalar,and error variances) and factor mean scores equivalencies of a modified version of the Strengths and Weaknesses of ADHDSymptoms and Normal Behavi... The study examined the measurement invariance (configural,metric,scalar,and error variances) and factor mean scores equivalencies of a modified version of the Strengths and Weaknesses of ADHDSymptoms and Normal Behavior Scale (SWAN-M) across ratings provided by mothers of clinic-referred children and adolescents,diagnosed with (N = 666) and without (N = 202) ADHD. Confirmatory factor analysis (CFA) of these ratings provided support for the bi-factor model of ADHD [orthogonal general and specific factors for inattention (IA) and hyperactivity/impulsivity (HI) symptoms]. Multiple-group confirmatory factor analysis (CFA) of the bi-factor model supported full measurement invariance. Findings also showed that for latent mean scores,the ADHD group had higher scores than the non-ADHD group for the ADHD general and IA specific factors. The findings indicate that observed scores (based on maternal ratings of the SWAN-M) are comparable,as they have the same measurement properties. The theoretical,psychometric and clinical implications of the findings are discussed. 展开更多
关键词 strengths and weaknesses of ADHD-Symptoms and Normal Behavior scale factor structure measurement INVARIANCE children and adolescents mother RATINGS
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Study of acute stroke clinical measuring scale
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作者 张海南 胡治平 +1 位作者 蒋波 宋兴旺 《中国临床康复》 CSCD 2002年第23期3614-3615,共2页
Objective To explore the possibility of diagnosis types of acute stroke, elevating treatment quality and promoting prognosis with acute stroke clinical measuring scale . Methods To gain a measuring scale formula and s... Objective To explore the possibility of diagnosis types of acute stroke, elevating treatment quality and promoting prognosis with acute stroke clinical measuring scale . Methods To gain a measuring scale formula and simplify this formula after stepwise regression Fisher distinguish analysis to 18 clinical variable of 184 acute stroke patients and to validate its sensitivity, specificity and positive foretell value to diagnosis of acute stroke. Results We gained scale that Y=0.617×action+0.485×BP+1.241×headache+0.74×vomiting+0.955×cervical resistance-1.215×TIA-0.727×heart disease-2.78;sensitivity of this formula to diagnosis of cerebral infarction and cerebral hemorrhage was 90.5%and 70%respectively,its specificity was 70%and 90.5%respectively,positive foretell value was 71.7%and 89.7%(Y≥0 means cerebral hemorrhage,Y<0 means cerebral infarction). Simple formula is S=0.5×action+0.5×BP+1×headache+1×vomiting+1×cervical resistance-1×TIA-1×hear disease-3;its sensitivity was 89.3%and 68%,specificity was 68%and 89.3%,positive foretell value was 70.1%and 88.3%.There was no apparent difference in sensitivity; specificity and positive foretell value between two formulas. Conclusion Acute stroke clinical measuring scale can help early diagnosis, treatment and rehabilitation of cerebral stroke patients. 展开更多
关键词 急性脑卒中 临床计量量表 诊断 神经功能
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Shape Measures for the Distribution of a Qualitative Variable
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作者 José Moral de la Rubia 《Open Journal of Endocrine and Metabolic Diseases》 2023年第4期619-634,共16页
There are several shape measures for quantitative variables, some of which can also be applied to ordinal variables. In quantitative variables, symmetry, peakedness, and kurtosis are essential properties to evaluate t... There are several shape measures for quantitative variables, some of which can also be applied to ordinal variables. In quantitative variables, symmetry, peakedness, and kurtosis are essential properties to evaluate the deviation from assumptions, particularly normality. They aid in selecting the most appropriate method for estimating parameters and testing hypotheses. Initially, these properties serve a descriptive role in qualitative variables. Once defined, they can be considered to check for non-compliance with assumptions and to propose modifications for testing procedures. The objective of this article is to present three measures of the shape of the distribution of a qualitative variable. The concepts of qualitative asymmetry and peakedness are defined. The measurement of the first concept involves calculating the average frequency difference between qualitative categories matched by frequency homogeneity or proximity. For the second concept, the peak-to-shoulder difference and the qualitative percentile kurtosis are taken into consideration. This last measurement is a less effective option than the peak-to-shoulder difference to measure peakedness. A simulated example of the application of these three measures is given and the paper closes with some conclusions and suggestions. 展开更多
关键词 SYMMETRY Peakedness Descriptive measures Nominal measurement scale Qualitative Variables
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Shape Measures for the Distribution of a Qualitative Variable
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作者 José Moral de la Rubia 《Open Journal of Statistics》 2023年第4期619-634,共16页
There are several shape measures for quantitative variables, some of which can also be applied to ordinal variables. In quantitative variables, symmetry, peakedness, and kurtosis are essential properties to evaluate t... There are several shape measures for quantitative variables, some of which can also be applied to ordinal variables. In quantitative variables, symmetry, peakedness, and kurtosis are essential properties to evaluate the deviation from assumptions, particularly normality. They aid in selecting the most appropriate method for estimating parameters and testing hypotheses. Initially, these properties serve a descriptive role in qualitative variables. Once defined, they can be considered to check for non-compliance with assumptions and to propose modifications for testing procedures. The objective of this article is to present three measures of the shape of the distribution of a qualitative variable. The concepts of qualitative asymmetry and peakedness are defined. The measurement of the first concept involves calculating the average frequency difference between qualitative categories matched by frequency homogeneity or proximity. For the second concept, the peak-to-shoulder difference and the qualitative percentile kurtosis are taken into consideration. This last measurement is a less effective option than the peak-to-shoulder difference to measure peakedness. A simulated example of the application of these three measures is given and the paper closes with some conclusions and suggestions. 展开更多
关键词 SYMMETRY Peakedness Descriptive measures Nominal measurement scale Qualitative Variables
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Validation of LPD Scale for the Assessment of Pressure Ulcer at Home
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作者 Renzo Zanotti Maddalena Segala Anna Bovo 《Open Journal of Nursing》 2023年第5期267-282,共16页
Objectives: This study was designed to test and validate the new LPD scale in a home care setting. The specific objectives are to validate the LPD scale for subjects cared for at home;and to compare LPD to the Braden ... Objectives: This study was designed to test and validate the new LPD scale in a home care setting. The specific objectives are to validate the LPD scale for subjects cared for at home;and to compare LPD to the Braden scale for internal validity. Method: This multicenter, cross-sectional study was conducted in the domestic environment of subjects cared for Home Care services from North to South of Italy. Data collection lasted 8 months, between June 2018 and September 2020, and consisted of the simultaneous compilation of the new LPD, and the Braden scale. Home Care Expert nurses could interface with the recruited subjects and/or caregivers. The parameters considered to validate the new scale were sensitivity (Se), specificity (Sp), positive predictive values (PPV), odds ratio (OR), and the area under the receiver operating characteristic (ROC) curve. Results: Of the 679 recruited subjects, 63.2% were women, and more than 50% did not have a pressure ulcer. 48.2% of the sample aged over 85 years old;69% was affected by multiple disease, and 76.6% took a lot of drugs. 91.6% of the subjects were affected by a partial or total functional dependency. Around 50% of subjects presented double incontinence, and 43% were conscious and collaborated. 85.4% of subjects lived in a healthy environment. The predictive validity parameters showed: Se 77.25%, Sp 84.04%, PPV 91.37%, and the area under the curve (AUC) 0.88% with a confidence interval (CI) 95%. These values mean a moderately accuracy of the test. Conclusions: The new LPD scale has demonstrated a good capacity for identifying the subjects at risk of pressure ulcer and had a better discriminatory power rather than Braden scale. 展开更多
关键词 Pressure Ulcers Sores Home Care VALIDATION measurement scale
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基于激光干涉仪同步测量的动态校准装置
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作者 任瑜 胡晓磊 +2 位作者 郭志敏 傅云霞 张丰 《计量学报》 CSCD 北大核心 2024年第3期349-355,共7页
为满足时变几何量的瞬时动态测试需求,研制了一种基于激光干涉仪同步测量的动态校准装置。该装置采用直线运动导轨和运动发生器、长度标准器激光干涉仪,以基于GNSS驯服时钟的同步触发器实现同步测量并确保时间准确稳定,并使用动态校准... 为满足时变几何量的瞬时动态测试需求,研制了一种基于激光干涉仪同步测量的动态校准装置。该装置采用直线运动导轨和运动发生器、长度标准器激光干涉仪,以基于GNSS驯服时钟的同步触发器实现同步测量并确保时间准确稳定,并使用动态校准软件实现控制一体化。经综合分析激光干涉仪的最大允许误差、直线运动导轨的直线度、环境因素、触发信号间时延及激光干涉仪测量时延等因素,该装置的长度示值的测量不确定度为Q[1.8μm,3×10^(-7)L](k=2)。与同型号激光干涉仪的比对实验和激光跟踪仪瞬时长度测试实验,证明了不确定度评定的合理性以及该装置在瞬时动态准确度测试中的可行性。 展开更多
关键词 几何量计量 动态校准 激光干涉仪 同步测量 大尺寸测量 时变几何量
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一种应用于大尺寸测量系统的坐标系自动标定方法
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作者 张晓晖 张嘉颖 +5 位作者 刘青 李金童 杨启航 吕佳铭 尚婷 成鹏飞 《光子学报》 EI CAS CSCD 北大核心 2024年第3期167-179,共13页
针对现有方法在标定过程中过于繁琐的问题,提出了一种应用于大尺寸测量系统的坐标系全自动标定方法。该方法通过固定两个在测量单元局部坐标系已知坐标的测量节点作为标记靶,测量单元之间相互测量彼此的标记靶获得标记靶上的测量点在不... 针对现有方法在标定过程中过于繁琐的问题,提出了一种应用于大尺寸测量系统的坐标系全自动标定方法。该方法通过固定两个在测量单元局部坐标系已知坐标的测量节点作为标记靶,测量单元之间相互测量彼此的标记靶获得标记靶上的测量点在不同坐标系下的坐标值,利用这些坐标值建立三维几何约束,从而自动标定不同坐标系之间的坐标转换关系。借助于精密激光定位系统平台进行实验验证,结果表明,所提方法可以实现测量单元局部坐标系之间的自动标定,降低了坐标系标定过程中的人工成本。在距离测量单元布站区域约2 m,大小为5 000 mm×5 000 mm×500 mm的测量空间中长度测量的精度在0.46 mm/m以内,测试点三维坐标测量的标准偏差在0.026 mm以内,可以满足绝大部分工业测量的需求。该方法极大的提高了系统的标定效率,有望为具有自动标定功能的大尺寸测量设备的产品化提供新的理论基础。 展开更多
关键词 大尺寸测量系统 自动标定 标记靶 几何约束 工业测量
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新型旋转激光扫描系统轴系调整与误差标定
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作者 任永杰 郭威 +3 位作者 吴腾飞 滕明鑫 林嘉睿 邾继贵 《光学精密工程》 EI CAS CSCD 北大核心 2024年第8期1111-1121,共11页
旋转激光扫描系统是一种基于精密转台结合多路激光的空间多目标并行角度传感系统。为改善系统光源性能,设计了一种采用光纤从外部导入光源的新型轴系结构。但是当激光以一定角度穿过中空的转轴进入镜组后,若倾斜入射柱镜,将导致出射的... 旋转激光扫描系统是一种基于精密转台结合多路激光的空间多目标并行角度传感系统。为改善系统光源性能,设计了一种采用光纤从外部导入光源的新型轴系结构。但是当激光以一定角度穿过中空的转轴进入镜组后,若倾斜入射柱镜,将导致出射的扫描光面型发生变化。针对此问题,研究了一种基于平行线的传递性的激光光轴姿态的调整方法,并借助激光跟踪仪测量平台,分别对光轴与转轴轴系进行拟合,建立了对光轴倾斜误差的标定方法。实验结果表明,调整后光轴与转轴轴线的空间夹角优于0.15°,完全满足扫描光截面中心直线度对激光入射柱镜的角度要求。该调整方案可用于系统的装配环节,使扫描光更加接近理想平面,有助于系统测量精度的提升。 展开更多
关键词 大尺寸测量 旋转激光扫描系统 光轴调整 轴线拟合 误差分析
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基于“四象限模型”的医患信任测量量表构建及初步研究
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作者 崔明武 王振辉 +5 位作者 赵刚 刘伟 赵红 沈丹薇 张静涛 曹天宇 《中国疗养医学》 2024年第4期1-4,共4页
目的 通过构建适宜我国应用的“四象限模型”医患信任测量量表,评价分析其效度及信度,为改善医患关系提供一定的帮助。方法 本文以国外学者研究的“四象限模型”为理论框架,通过文献回顾、访谈法、德尔菲专家咨询法等多种方式构建“四... 目的 通过构建适宜我国应用的“四象限模型”医患信任测量量表,评价分析其效度及信度,为改善医患关系提供一定的帮助。方法 本文以国外学者研究的“四象限模型”为理论框架,通过文献回顾、访谈法、德尔菲专家咨询法等多种方式构建“四象限模型”医患信任测量量表,将某院作为实际研究的案例,对“四象限模型”医患信任测量量表的信度、效度进行检验。结果 “四象限模型”医患信任测量量表的总Cronbach’s α信度系数为0.912;分半信度R为0.863和0.932;内容效度Pearson相关系数0.38~0.81,均具有统计学意义;结构效度RMR为0.065,RMSEA为0.073,χ~2/df为2.236,GFI为0.791。结论 经过某医院的实证检验,“四象限模型”医患信任测量量表具有较高的信度和较好的效度,可为我国医患信任方面研究提供一个科学的、合理的、有效的并且符合我国国情的医患信任测量量表,在重构医患信任、改善医患关系方面有着广阔的应用前景。 展开更多
关键词 医患信任 四象限模型 测量量表 效度 信度
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