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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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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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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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Novel Method for Spatial Angle Measurement Based on Rotating Planar Laser Beams 被引量:19
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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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大规模教育考试评价的变革与发展趋向
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作者 辛涛 杨丽萍 《中国考试》 北大核心 2025年第2期1-11,共11页
聚焦于国际大规模教育考试的演变趋势,本文探讨了教育考试为适应未来人才选拔与培养需求所进行的多方面变革。通过梳理近年来国际组织及各国在大规模教育考试中的理念和技术革新,阐述了教育考试理论、构念、命题以及交互式、个性化测试... 聚焦于国际大规模教育考试的演变趋势,本文探讨了教育考试为适应未来人才选拔与培养需求所进行的多方面变革。通过梳理近年来国际组织及各国在大规模教育考试中的理念和技术革新,阐述了教育考试理论、构念、命题以及交互式、个性化测试方法的发展情况。尤其是在人工智能技术深度融入的形势下,大规模教育考试面对诸多争议,在信度与效度等方面也面临新挑战。本文还强调了数字化环境中构建教育考试标准和规范的重要性,为推进我国教育考试现代化提出参考建议。 展开更多
关键词 教育考试 大规模考试 构念 命题 教育测量标准 教育评价改革
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工作场所感恩量表跨性别测量等值性检定研究
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作者 夏静波 蓝淼东 《黑龙江科学》 2025年第1期90-93,共4页
为在国内企业员工中检验工作场所感恩量表的稳定性及跨性别测量的等值性,对369名企业员工的有效样本数据进行验证性因子分析与多群组验证性因子分析。研究结果支持工作场所感恩量表的二因子结构,分别是对支持性工作环境的感恩与对有意... 为在国内企业员工中检验工作场所感恩量表的稳定性及跨性别测量的等值性,对369名企业员工的有效样本数据进行验证性因子分析与多群组验证性因子分析。研究结果支持工作场所感恩量表的二因子结构,分别是对支持性工作环境的感恩与对有意义的工作的感恩,该因子结构对男性或女性员工皆适用。工作场所感恩量表在我国企业员工中具有良好的信度与效度,对不同性别员工的测量效果不存在差异,适宜成为开展工作场所感恩相关研究的工具。 展开更多
关键词 工作场所感恩 工作场所感恩量表 测量等值
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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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面向微震时序波形的无监督聚类方法
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作者 罗浩 葛颂 +2 位作者 潘一山 张欢 刘中一 《计算机工程与设计》 北大核心 2025年第1期198-205,共8页
为更加快速准确地从微震时序数据中提取微震事件,提高异常事件的捕捉效率,提出一种基于多尺度融合卷积和空洞卷积的自动编码器(multi-scale fusion convolution and dilated convolutions auto encoder,MDCAE)与融合波动率和限制窗口的... 为更加快速准确地从微震时序数据中提取微震事件,提高异常事件的捕捉效率,提出一种基于多尺度融合卷积和空洞卷积的自动编码器(multi-scale fusion convolution and dilated convolutions auto encoder,MDCAE)与融合波动率和限制窗口的动态时间扭曲(constraints dynamic time warping for fusing volatility,CDTW-Vol)方法。提出MDCAE的特征提取方法,将波形信号转变为低维特征信号,引入微震波形的波动率的概念,通过改进后的DTW算法对特征信号进行相似性度量,得到的相似性矩阵进行k-medoids聚类,得到聚类结果。应用某矿区501工作面和802工作面微震监测数据集进行实验,验证所提方法的准确性和泛化性,经实验得出所提聚类方法轮廓系数89%,兰德系数90%,相比普通的k-medoids聚类算法聚类精度上升57%,为捕捉微震系统的异常事件提供了一种新方法。 展开更多
关键词 微震时间序列 多尺度融合卷积 波动率 相似性度量 无监督聚类 特征提取 动态时间规整
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基于完全但不完美信息序贯博弈计量模型的农地流转影响因素分析
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作者 蔡鑫宇 林益忠 《嘉兴大学学报》 2025年第1期97-106,共10页
农业规模经营可以提高农业生产效率、实现农业现代化,而规模经营的前提是农地流转,这一前提是买卖双方经过博弈后的均衡结果。通过构建完全但不完美信息序贯博弈计量模型,分析农地流转的影响因素:将2020年CFPS微观数据库中4 579户农户... 农业规模经营可以提高农业生产效率、实现农业现代化,而规模经营的前提是农地流转,这一前提是买卖双方经过博弈后的均衡结果。通过构建完全但不完美信息序贯博弈计量模型,分析农地流转的影响因素:将2020年CFPS微观数据库中4 579户农户家庭数据随机分为两部分,80%用于实证分析,其余20%用于检验模型准确度,所建模型准确度高达86.52%,高于二元Logit模型。结果表明:农地流转市场为买方利益驱动市场,户主因素、家庭因素、村庄特征和地区特征均对农地流转有着不同程度的影响。提出了保障耕地收入、提高农村社会保障水平、增加转移性收入、促进农民非农就业以及推进农村基础交通设施建设等对策建议。 展开更多
关键词 农地流转 规模经营 序贯博弈 计量模型
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大型水利枢纽工程实施阶段投资控制措施及方法
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作者 黄德法 于良 《云南水力发电》 2025年第1期173-176,共4页
大型水利枢纽工程具有投资大,技术复杂、建设期长,移民征地范围广等特点,工程实施阶段的投资控制是项目管理的主要目标之一,也是保证项目整体目标实现的关键。以海南省南渡江迈湾水利枢纽这一大型水利工程为例,结合项目的自身特点,分别... 大型水利枢纽工程具有投资大,技术复杂、建设期长,移民征地范围广等特点,工程实施阶段的投资控制是项目管理的主要目标之一,也是保证项目整体目标实现的关键。以海南省南渡江迈湾水利枢纽这一大型水利工程为例,结合项目的自身特点,分别从投资控制的具体措施及方法上进行研究,从组织、经济、技术、合同措施以及事前、事中、事后控制方法上提出适用于该项目实施阶段的投资控制方案,并应用于项目的投资控制实践中。 展开更多
关键词 大型水利枢纽 实施阶段 投资控制措施及方法
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Simulation of leaf area index and biomass at landscape scale 被引量:7
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作者 ZHANGNa YUGuirui +1 位作者 YUZhenliang ZHAOShidong 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期139-152,共14页
The method for simulating the temporal and spatial distribution patterns of leaf area index (LAI) and biomass at landscape scale using remote sensing images and surface data was discussed in this paper. The procedure... The method for simulating the temporal and spatial distribution patterns of leaf area index (LAI) and biomass at landscape scale using remote sensing images and surface data was discussed in this paper. The procedure was: (1) annual maximum normalized difference vegetation index (NDVI) over the landscape was calculated from TM images; (2) the relationship model between NDVI and LAI was built and annual maximum LAI over the landscape was simulated; (3) the relationship models between LAI and biomass were built and annual branch, stem, root and maximum leaf biomass over the landscape were simulated; (4) spatial distribution patterns of leaf biomass and LAI in different periods all the year round were obtained. The simulation was based on spatial analysis module GRID in ArcInfo software. The method is also a kind of scaling method from patch scale to landscape scale. A case study of Changbai Mountain Nature Reserve was dissertated. Analysis and primary validation were carried out to the simulated LAI and biomass for the major vegetation types in the Changbai Mountain in 1995. 展开更多
关键词 landscape scale leaf area index BIOMASS remote sensing field measurement CLC number:Q948.2 TP79
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Intensity measures for the seismic response evaluation of buried steel pipelines under near-field pulse-like ground motions 被引量:3
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作者 Alireza Kiani Mehdi Torabi S.Mohammad Mirhosseini 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第4期917-931,共15页
Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, h... Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, have a key role in performance-based earthquake engineering. Many studies have been carried out on the determination of suitable IMs in terms of effi ciency, suffi ciency and scaling robustness. The majority of these investigations focused on ordinary structures such as buildings and bridges, and only a few were about buried pipelines. In the current study, the optimal IMs for predicting the seismic demand of continuous buried steel pipelines under near-fi eld pulse-like ground motion records is investigated. Incremental dynamic analysis is performed using twenty ground motion records. Using the results of the regression analysis, the optimality of 23 potential IMs are studied. It is concluded that specifi c energy density (SED) followed by VSI[ω1(PGD+RMSd )] are the optimal IMs based on effi ciency, suffi ciency and scaling robustness for seismic response evaluation of buried pipelines under near-fi eld ground motions. 展开更多
关键词 continuous BURIED steel PIPELINE intensity measure SCALING robustness pulse-like ground motion RECORDS performance-based EARTHQUAKE engineering
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