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Sinicization and psychometric validation of the German Pelvic Floor Questionnaire for Pregnant and Postpartum Women
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作者 ZHU Liping ZHOU Chengyu +2 位作者 LI Xuhong HOU Qiao YANG Shuo 《中南大学学报(医学版)》 北大核心 2025年第1期72-80,共9页
Objective:Pelvic floor dysfunction is common among pregnant and postpartum women and significantly impacts quality of life.This study aims to translate the German Pelvic Floor Questionnaire for Pregnant and Postpartum... Objective:Pelvic floor dysfunction is common among pregnant and postpartum women and significantly impacts quality of life.This study aims to translate the German Pelvic Floor Questionnaire for Pregnant and Postpartum Women into Chinese and to evaluate its reliability and validity in the Chinese population.Methods:The questionnaire was translated using the Brislin model.A cross-sectional study was conducted among pregnant and postpartum women to assess the content validity,construct validity,Cronbach’sαcoefficient,test-retest reliability,and split-half reliability of the Chinese version.Results:A total of 72 women were included,with 6.9% being pregnant and 93.1% postpartum;the age was(32.3±3.6)years.The Chinese version of the questionnaire contains 4 dimensions and 45 items.The content validity index of individual items ranged from 0.833 to 1.000,with a scale-level content validity index of 0.977 and intraclass correlation coefficients(ICCs)exceeding 0.90.The overall Cronbach’s α coefficient was 0.891,with subscale coefficients ranging from 0.732 to 0.884(all ICCs>0.70).The testretest reliability of the total scale was 0.833,and for the 4 dimensions,bladder,bowel,prolapse,and sexual function,the values were 0.776,0.579,0.732,and 0.645,respectively.The split-half reliability was 0.74.Conclusion:The Chinese version of the questionnaire demonstrated good reliability and validity,indicating its applicability in assessing pelvic floor dysfunction and associated risk factors during pregnancy and postpartum. 展开更多
关键词 pelvic floor dysfunction PREGNANCY postpartum women QUESTIONNAIRE RELIABILITY validity
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System design and validation of Queqiao-2 lunar relay communication satellite 被引量:2
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作者 ZHANG Lihua XIONG Liang +11 位作者 SUN Ji CHEN Luojing XIAO Chuan ZHOU Wenyan WANG Yong LIU Wangwang GUAN Yifeng CHEN Tao YU Xiaochuan XU Jin CHEN Guohui CAO Xiaoping 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第5期23-39,共17页
In order to provide relay communication supports for future Chinese lunar exploration program,Queqiao-2 relay communication satellite was developed.Queqiao-2 can perform scientific observations with three kinds of sci... In order to provide relay communication supports for future Chinese lunar exploration program,Queqiao-2 relay communication satellite was developed.Queqiao-2 can perform scientific observations with three kinds of scientific instruments on board.The system design of Queqiao-2,including mission orbit and transfer orbit design,configuration and layout design,housekeeping and information flow design,power supply and distribution design,GNC and propulsion system design,communication links design,etc.,was accomplished through comprehensive tradeoff and evaluation on technical maturity,availability,schedule,cost,and so on.With a view to reducing development risk,both the platform and relay communication payloads were developed based on significant heritage from previous Queqiao relay satellite and other relevant spacecraft.Queqiao-2 features flexible system architecture to support multiple frequencies,modulations,data rates and software reconfigurations to meet new user requirements.Subsequent to a successful launch on March 20,2024,by means of 5 orbit maneuvers,Queqiao-2 was inserted into a highly elliptical frozen mission orbit around the moon with a 24h period on schedule.Following on-orbit tests and calibrations,Queqiao-2 has possessed the capacity to provide reliable relay communication services to multiple lunar exploration missions,as well as the capacity to perform scientific observations.Under the support of Queqiao-2,Chang′e-6 achieved its ambitious mission goal to collect and return samples from the moon′s mysterious far side.In the meanwhile,Queqiao-2 has also paved the way for the following Chinese lunar exploration missions including Chang′e-7 and Chang′e-8.The design life time of Queqiao-2 is more than 8 years.Benefit from flexibility and extensibility of relay communication system design,it is convenient to provide relay communication services for future lunar exploration missions of both China and other countries.In addition,innovative scientific observations would be performed during the period that no relay communication task is arranged.The system design of Queqiao-2 reflects the development philosophy of technical innovations and inheritance integration.Based on highly flexible and extensible system architecture,multiple and concurrent relay communication mission requirements can be met.It can provide strong supports for future lunar exploration missions.Successful launching,orbit entering and on-orbit tests of Queqiao-2 verified the correct design principle and versatility.By means of Queqiao-2,more innovative scientific outcomes are anticipated and lunar exploration activities can be facilitated. 展开更多
关键词 lunar explorations relay communication Queqiao system design TEST validation
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Adaptive Robust Servo Control for Vertical Electric Stabilization System of Tank and Experimental Validation 被引量:2
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作者 Darui Lin Xiuye Wang +1 位作者 Yimin Wang Guolai Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期326-342,共17页
A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevaryin... A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevarying but bounded uncertainty within the vertical electric stabilization system:model parameter uncertainty and uncertain nonlinearity.First,the vertical electric stabilization system is constructed as an uncertain nonlinear dynamic system that can reflect the practical mechanics transfer process of the system.Second,the dynamical equation in the form of state space is established by designing the angular tracking error.Third,the comprehensive parameter of system uncertainty is designed to estimate the most conservative effects of uncertainty.Finally,an adaptive robust servo control which can effectively handle the combined effects of complex nonlinearity and uncertainty is proposed.The feasibility of the proposed control strategy under the practical physical condition is validated through the tests on the experimental platform.This paper pioneers the introduction of the internal nonlinearity and uncertainty of the vertical electric stabilization system into the settlement of the tracking stability control problem,and validates the advanced servo control strategy through experiment for the first time. 展开更多
关键词 Adaptive robust servo control Experimental validation Nonlinearity compensation System uncertainty Vertical electric stabilization system
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An internal ballistic model of electromagnetic railgun based on PFN coupled with multi-physical field and experimental validation 被引量:1
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作者 Benfeng Gu Haiyuan Li Baoming Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期254-261,共8页
To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore damage.In this paper,a three-dime... To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore damage.In this paper,a three-dimensional numerical model of the augmented railgun with four parallel unconventional rails is introduced to simulate the internal ballistic process and realize the multi-physics field coupling calculation of the rail gun,and a test experiment of a medium-caliber electromagnetic launcher powered by pulse formation network(PFN)is carried out.Various test methods such as spectrometer,fiber grating and high-speed camera are used to test several parameters such as muzzle initial velocity,transient magnetic field strength and stress-strain of rail.Combining the simulation results and experimental data,the damage condition of the contact surface is analyzed. 展开更多
关键词 Internal ballistic modeling Electromagnetic rail gun Multi-physics field coupling Experimental validation PFN
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Characterization of a Powertrain Test Bed in the Context of Virtual Validation of Drivability
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作者 Schmidt HENRIK Prokop GÜNTHER 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第S01期9-19,共11页
Technological trends in the automotive industry toward a software-defined and autonomous vehicle require a reassessment of today’s vehicle development process.The validation process soaringly shapes after starting wi... Technological trends in the automotive industry toward a software-defined and autonomous vehicle require a reassessment of today’s vehicle development process.The validation process soaringly shapes after starting with hardware-in-the-loop testing of control units and reproducing real-world maneuvers and physical interaction chains.Here,the road-to-rig approach offers a vast potential to reduce validation time and costs significantly.The present research study investigates the maneuver reproduction of drivability phenomena at a powertrain test bed.Although drivability phenomena occur in the frequency range of most up to 30∙Hz,the design and characteristics substantially impact the test setup’s validity.By utilization of modal analysis,the influence of the test bed on the mechanical characteristic is shown.Furthermore,the sensitivity of the natural modes of each component,from either specimen or test bed site,is determined.In contrast,the uncertainty of the deployed measurement equipment also affects the validity.Instead of an accuracy class indication,we apply the ISO/IEC Guide 98 to the measurement equipment and the test bed setup to increase the fidelity of the validation task.In conclusion,the present paper contributes to a traceable validity determination of the road-to-rig approach by providing objective metrics and methods. 展开更多
关键词 powertrain test bed virtual validation modal analysis powertrain-hardware-in-the-loop DRIVABILITY measurement uncertainty
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基于Cross-Validation的小波自适应去噪方法 被引量:5
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作者 黄文清 戴瑜兴 李加升 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第11期40-43,共4页
小波去噪算法中,阈值的选择非常关键.提出一种自适应阈值选择算法.该算法先通过Cross-Validation方法将噪声干扰信号分成两个子信号,一个用于阈值处理,一个用作参考信号;再采用最深梯度法来寻求一个最优去噪阈值.仿真和实验结果表明:在... 小波去噪算法中,阈值的选择非常关键.提出一种自适应阈值选择算法.该算法先通过Cross-Validation方法将噪声干扰信号分成两个子信号,一个用于阈值处理,一个用作参考信号;再采用最深梯度法来寻求一个最优去噪阈值.仿真和实验结果表明:在均方误差意义上,所提算法去噪效果优于Donoho等提出的VisuShrink和SureShrink两种去噪算法,且不需要带噪信号的任何'先验信息',适应于实际信号去噪处理. 展开更多
关键词 小波变换 Cross-validation 自适应滤波 阈值
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非参数回归的L_1-cross-validation最近邻估计的强相合性
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作者 杨瑛 《甘肃农业大学学报》 CAS CSCD 1993年第2期150-154,共5页
考虑非参数回归模型:Y_i=g(x_i)+e_i,i≥1,其中g是待估计的连续函数,{x_i,i≥1}是非随机的,{e_i,i≥1)是iid随机误差。在本文中,我们讨论最近邻估计g_(n,h)(x)=1/h∑Y_(R_(i,x)^(n)),其中h利用L_1-cross-validation方法选择,在一定条件... 考虑非参数回归模型:Y_i=g(x_i)+e_i,i≥1,其中g是待估计的连续函数,{x_i,i≥1}是非随机的,{e_i,i≥1)是iid随机误差。在本文中,我们讨论最近邻估计g_(n,h)(x)=1/h∑Y_(R_(i,x)^(n)),其中h利用L_1-cross-validation方法选择,在一定条件下,证明了L_1-cross-validation最近邻估计的强相合性。 展开更多
关键词 最近邻估计 强相合性 非参数回归
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Verification and validation of detonation modeling 被引量:8
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作者 Xiao Liang Rui-li Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第3期398-408,共11页
The mathematical model used to describe the detonation multi-physics phenomenon is usually given by highly coupled nonlinear partial differential equations. Numerical simulation and the computer aided engineering (CAE... The mathematical model used to describe the detonation multi-physics phenomenon is usually given by highly coupled nonlinear partial differential equations. Numerical simulation and the computer aided engineering (CAE) technique has become the third pillar of detonation research, along with theory and experiment, due to the detonation phenomenon is difficult to explain by the theoretical analysis, and the cost required to accredit the reliability of detonation products is very high, even some physical experiments of detonation are impossible. The numerical simulation technique can solve these complex problems in the real situation repeatedly and reduce the design cost and time stunningly. But the reliability of numerical simulation software and the serviceability of the computational result seriously hinders the extension, application and the self-restoration of the simulation software, restricts its independently innovational ability. This article deals with the physical modeling, numerical simulation, and software development of detonation in a unified way. Verification and validation and uncertainty quantification (V&V&UQ) is an important approach in ensuring the credibility of the modeling and simulation of detonation. V&V of detonation is based on our independently developed detonation multiphysics software-LAD2D. We propose the verification method based on mathematical theory and program function as well as availability of its program execution. Validation is executed by comparing with the experiment data. At last, we propose the future prospect of numerical simulation software and the CAE technique, and we also pay attention to the research direction of V&V&UQ. 展开更多
关键词 VERIFICATION and validation DETONATION EQUATION of state DETONATION DIFFRACTION REACTION rate LAW
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Fast cross validation for regularized extreme learning machine 被引量:9
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作者 Yongping Zhao Kangkang Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期895-900,共6页
A method for fast 1-fold cross validation is proposed for the regularized extreme learning machine (RELM). The computational time of fast l-fold cross validation increases as the fold number decreases, which is oppo... A method for fast 1-fold cross validation is proposed for the regularized extreme learning machine (RELM). The computational time of fast l-fold cross validation increases as the fold number decreases, which is opposite to that of naive 1-fold cross validation. As opposed to naive l-fold cross validation, fast l-fold cross validation takes the advantage in terms of computational time, especially for the large fold number such as l 〉 20. To corroborate the efficacy and feasibility of fast l-fold cross validation, experiments on five benchmark regression data sets are evaluated. 展开更多
关键词 extreme learning machine (ELM) regularization theory cross validation neural networks.
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A New Method with High Confidence for Validation of Computer Simulation Models of Flight Systems 被引量:5
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作者 Zhou XianminShanghai Research & Development Centre, 412 Guil in Road, Shanghai 200233, P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第4期43-52,共10页
Computer simulation models may by used to gain further information about missile performance variability. Model validation is an important aspect of the test program for a missile system. Validation provides a basis f... Computer simulation models may by used to gain further information about missile performance variability. Model validation is an important aspect of the test program for a missile system. Validation provides a basis for confidence in the model's results and is a necessary step if the model is to be used to draw inference about the behavior of the real missile. This paper is a review of methods useful for validation of computer simulation models of missile systems and provides a new method with high degree of confidence for validation of computer simulation models of missile systems. Some examples of the use of the new method in validating computer simulation models are given. 展开更多
关键词 Model validation Model credibility Simulation modeling System simulation.
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Improvement of GPS ambiguity resolution using prior height information. Part Ⅰ: The method by using height validation 被引量:5
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作者 朱建军 Rock Santerre 《Journal of Central South University of Technology》 2002年第3期186-190,共5页
It is an attractive method to combine GPS observations with the information from other surveying system to improve the ambiguity resolution. This research is conducted to investigate how to obtain the prior height inf... It is an attractive method to combine GPS observations with the information from other surveying system to improve the ambiguity resolution. This research is conducted to investigate how to obtain the prior height information in bathymetric surveying by GPS positioning and how to use the prior height information and to obtain a robust result. The authors deal with the collection and the description of the prior height and the method using height validation to improve the ambiguity resolution. The principle of the method, the relationships between the height threshold and the ambiguity search space are presented. A method to determine the threshold for the height validation is suggested. The field tests are carried out to show the feasibility of the proposed methods. 展开更多
关键词 AMBIGUITY resolution HEIGHT validation ROBUSTNESS OTF techniques
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EMMD-Prony approach for dynamic validation of simulation models 被引量:3
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作者 Yongxing Chen Xiaoyan Wu +1 位作者 Xiangwei Bu Ruiyang Bai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期172-181,共10页
Model validation and updating is critical to model credibility growth. In order to assess model credibility quantitatively and locate model error precisely, a new dynamic validation method based on extremum field mean... Model validation and updating is critical to model credibility growth. In order to assess model credibility quantitatively and locate model error precisely, a new dynamic validation method based on extremum field mean mode decomposition(EMMD) and the Prony method is proposed in this paper. Firstly, complex dynamic responses from models and real systems are processed into stationary components by EMMD. These components always have definite physical meanings which can be the evidence about rough model error location. Secondly, the Prony method is applied to identify the features of each EMMD component. Amplitude similarity, frequency similarity, damping similarity and phase similarity are defined to describe the similarity of dynamic responses.Then quantitative validation metrics are obtained based on the improved entropy weight and energy proportion. Precise model error location is realized based on the physical meanings of these features. The application of this method in aircraft controller design provides evidence about its feasibility and usability. 展开更多
关键词 dynamic validation extremum field mean mode decomposition(EMMD) Prony method error location model updating
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Hover performance estimation and validation of battery powered vertical takeoff and landing aircraft 被引量:2
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作者 王波 侯中喜 +1 位作者 鲁亚飞 朱雄峰 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第10期2595-2603,共9页
Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, mot... Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, motor and electronic speed controller, the power consumption model of propeller and the constant power discharge model of battery, an efficient method to estimate the hover endurance of battery powered VTOL aircraft was presented. In order to understand the mechanism of performance improvement, the impacts of propulsion system parameters on hover endurance were analyzed by simulations, including the motor power density, the battery capacity, specific energy and Peukert coefficient. Ground experiment platform was established and validation experiments were carried out, the results of which showed a well agreement with the simulations. The estimation method and the analysis results could be used for optimization design and hover performance evaluation of battery powered VTOL aircraft. 展开更多
关键词 vertical takeoff and landing hover endurance estimation battery powered aircraft experimental validation
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Dynamic simulation of pilot thickener operation using phenomenological model with results validation for continuous and discontinuous tests 被引量:1
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作者 Rahimi Mehdi Unesi Majid +1 位作者 Rezai Bahram Abdollahzadeh Ali 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1207-1216,共10页
The phenomenological theory of sedimentation-thickening processes predicts the settling behavior of a flocculated suspension in dependence of two functions, the batch flux density function and the effective solid stre... The phenomenological theory of sedimentation-thickening processes predicts the settling behavior of a flocculated suspension in dependence of two functions, the batch flux density function and the effective solid stress. These functions were determined using batch settling tests. The governing equations for sedimentation were then solved numerically for these functions and the predictions were compared to the experimental results from pilot scale thickener tests. Firstly, the continuous tests were performed in the plexiglass pilot thickener at different feed flow rates and discharge rates and the solid volume fraction of discharge, the bed height and the time were recorded for each condition. These tests were also simulated and it was observed that there is a good agreement between the results of continuous tests and the results of dynamic simulation. Secondly, the discontinuous tests were performed in the plexiglass pilot thickener at different feed flow rates with a discharge rate of zero. The bed formation rate was determined for each condition. These tests were also simulated and it was observed that there is a good agreement between the results of discontinuous tests and the results of simulation. 展开更多
关键词 dynamic simulation DEWATERING THICKENER behavior PILOT THICKENER validation
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An approach to wide-field imaging of linear rail ground-based SAR in high squint multi-angle mode 被引量:3
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作者 ZHANG Yuan ZHANG Qiming +4 位作者 WANG Yanping LIN Yun LI Yang BAI Zechao LI Fang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期722-733,共12页
Ground-based synthetic aperture radar(GB-SAR) has been successfully applied to the ground deformation monitoring.However, due to the short length of the GB-SAR platform, the scope of observation is largely limited. Th... Ground-based synthetic aperture radar(GB-SAR) has been successfully applied to the ground deformation monitoring.However, due to the short length of the GB-SAR platform, the scope of observation is largely limited. The practical applications drive us to make improvements on the conventional linear rail GB-SAR system in order to achieve larger field imaging. First, a turntable is utilized to support the rotational movement of the radar.Next, a series of high-squint scanning is performed with multiple squint angles. Further, the high squint modulation phase of the echo data is eliminated. Then, a new multi-angle imaging method is performed in the wave number domain to expand the field of view. Simulation and real experiments verify the effectiveness of this method. 展开更多
关键词 ground-based synthetic aperture radar(GB-SAR) high squint multi-angle
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Validation methodology for distribution-based degradation model 被引量:1
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作者 Yunxia Chen Zhiguo Zeng Rui Kang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第4期553-559,共7页
Distribution-based degradation models (or graphical approach in some literature) occur in a wide range of applications. However, few of existing methods have taken the validation of the built model into consideratio... Distribution-based degradation models (or graphical approach in some literature) occur in a wide range of applications. However, few of existing methods have taken the validation of the built model into consideration. A validation methodology for distribution-based models is proposed in this paper. Since the model can be expressed as consisting of assumptions of model structures and embedded model parameters, the proposed methodology carries out the validation from these two aspects. By using appropriate statistical techniques, the rationality of degradation distributions, suitability of fitted models and validity of degradation models are validated respectively. A new statistical technique based on control limits is also proposed, which can be implemented in the validation of degradation models' validity. The case study on degradation modeling of an actual accelerometer shows that the proposed methodology is an effective solution to the validation problem of distribution-based de qradation models. 展开更多
关键词 degradation model distribution-based degradationmodel graphical method model validation control limits.
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Research Progress in Digging and Validation of miRNA Target Genes Using Experimental Methods 被引量:1
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作者 Luo Xiao Bai Xi +4 位作者 Cai Hua Ji Wei Liu Xin Tang Li-li Zhu Yan-ming 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第2期86-96,共11页
MicroRNAs (miRNAs) are a group of regulatory RNAs that regulate gene expression post-transcriptionally by the degradation or translational inhibition of their target messenger RNAs (mRNAs). Regulation is accomplis... MicroRNAs (miRNAs) are a group of regulatory RNAs that regulate gene expression post-transcriptionally by the degradation or translational inhibition of their target messenger RNAs (mRNAs). Regulation is accomplished when the 22-25 nucleotide miRNAs bind to complementary sequences in the 3'-untranslated regions (UTR). One barrier to miRNA research is to find target genes. Although computational target predictions have shed light on important aspects of microRNA target recognition, questions remain concerning the rates of false positives. In addition, we do not completely understand how microRNAs can recognize and regulate their targets. As such, experimental positive predictions and allow for an unbiased stu ap dy proaches are required, which can reflect in vivo processes, eliminating false of microRNA target recognition. In this review, we summarized experimental approaches that have been described for the identification and validation of mRNA targets associated with specific miRNAs. 展开更多
关键词 MIRNA TARGET experimental validation
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Validation concurrency control protocol in parallel real-time database systems 被引量:3
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作者 LEI Xiang-dong(雷向东) YUAN Xiao-li(袁晓莉) 《Journal of Central South University of Technology》 2002年第3期197-201,共5页
In parallel real-time database systems, concurrency control protocols must satisfy time constraints as well as the integrity constraints. The authors present a validation concurrency control(VCC) protocol, which can e... In parallel real-time database systems, concurrency control protocols must satisfy time constraints as well as the integrity constraints. The authors present a validation concurrency control(VCC) protocol, which can enhance the performance of real-time concurrency control mechanism by reducing the number of transactions that might miss their deadlines, and compare the performance of validation concurrency control protocol with that of HP2PL(High priority two phase locking) protocol and OCC-TI-WAIT-50(Optimistic concurrency control-time interval-wait-50) protocol under shared-disk architecture by simulation. The simulation results reveal that the protocol the author presented can effectively reduce the number of transactions restarting which might miss their deadlines and performs better than HP2PL and OCC-TI-WAIT-50. It works well when arrival rate of transaction is lesser than threshold. However, due to resource contention the percentage of missing deadline increases sharply when arrival rate is greater than the threshold. 展开更多
关键词 PARALLEL DATABASE system REAL-TIME DATABASE CONCURRENCY control validation TRANSACTIONS
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Translation and validation of the Malay version of the short-form DASS-21 for the epidemiology survey of working population 被引量:3
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作者 Edimansyah Abdin Rusli Nordin Lin Naing 《海南医学院学报》 CAS 2010年第3期300-303,共4页
Increasing occurrences of mental health problems such as depression,anxiety and stress amongst workers presents practical demands for employers and occupational health practitioners to assess the self-perceived depres... Increasing occurrences of mental health problems such as depression,anxiety and stress amongst workers presents practical demands for employers and occupational health practitioners to assess the self-perceived depression,anxiety and stress in workers with reliable and valid instruments.The present study aims to validate the Malay version of the short form Depression Anxiety Stress Scale (DASS-21) among Malaysian workers designed to screen the self-reported of depression,anxiety and stress among workers in Malaysia.Eighty-eight workers of two major automotive assembly plants in Pekan,Pahang consented to participate in the study and was administered the Malay version of the DASS-21.Translation (English-Malay) and back translation (Malay-English) of the DASS-21 was made to ensure the face validity of the questionnaire.Reliability was determined using Cronbach's alpha for internal consistency whilst construct validity was assessed using the exploratory factor analysis (principal component analysis with varimax rotation).The results indicated that the Cronbach's alpha coefficients were acceptable for DASS-Depression (0.81),DASS-Anxiety (0.85) and DASS-Stress (0.85).Exploratory factor analysis showed three meaningful common factors that could explain the three theoretical dimensions or constructs of the DASS-21.The validation study suggests that the Malay version of DASS-21 is reliable and valid screening instruments for assessing self-reported depression,anxiety and stress in Malaysian working population. 展开更多
关键词 管理学 职业 焦虑 情绪
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Validation method for simulation models with cross iteration
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作者 FANG Ke ZHAO Kaibin ZHOU Yuchen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期555-563,共9页
Cross iteration often exists in the computational process of the simulation models, especially for control models. There is a credibility defect tracing problem in the validation of models with cross iteration. In ord... Cross iteration often exists in the computational process of the simulation models, especially for control models. There is a credibility defect tracing problem in the validation of models with cross iteration. In order to resolve this problem, after the problem formulation, a validation theorem on the cross iteration is proposed, and the proof of the theorem is given under the cross iteration circumstance. Meanwhile, applying the proposed theorem, the credibility calculation algorithm is provided, and the solvent of the defect tracing is explained. Further, based on the validation theorem on the cross iteration, a validation method for simulation models with the cross iteration is proposed, which is illustrated by a flowchart step by step. Finally, a validation example of a sixdegree of freedom (DOF) flight vehicle model is provided, and the validation process is performed by using the validation method. The result analysis shows that the method is effective to obtain the credibility of the model and accomplish the defect tracing of the validation. 展开更多
关键词 validation METHOD simulation model CROSS ITERATION validation THEOREM validation EXAMPLE
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