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The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study
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作者 Jieying Wu Shan Ye +2 位作者 Xiangyi Liu Yingsheng Xu Dongsheng Fan 《Neural Regeneration Research》 SCIE CAS 2025年第5期1505-1512,共8页
Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives ... Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis. 展开更多
关键词 amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread
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Non-equal-interval direct optimizing Verhulst model that x(n) be taken as initial value and its application 被引量:2
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作者 Luo, Youxin Chen, Mianyun +1 位作者 Che, Xiaoyi He, Zheming 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期17-21,共5页
To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) ... To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) of X(0) as the starting condition of the grey differential model. It optimizes a modified β value and the background value, and takes two times fitting optimization. The new model extends equal intervals to non-equal-intervals and is suitable for general data modelling and estimating parameters of the direct Verhulst GM(1,1). The new model does not need to pre-process the primitive data, nor accumulate generating operation (AGO) and inverse accumulated generating operation (IAGO). It is not only suitable for equal interval data modelling, but also for non-equal interval data modelling. As the new information is fully used and two times fitting optimization is taken, the fitting accuracy is the highest in all existing models. The example shows that the new model is simple and practical. The new model is worth expanding on and applying in data processing or on-line monitoring for tests, social sciences and other engineering sciences. 展开更多
关键词 grey system data processing Verhulst GM(1 1) non-equal interval direct modelling OPTIMUM background value two times fitting
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Time-varying confidence interval forecasting of travel time for urban arterials using ARIMA-GARCH model 被引量:6
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作者 崔青华 夏井新 《Journal of Southeast University(English Edition)》 EI CAS 2014年第3期358-362,共5页
To improve the forecasting reliability of travel time, the time-varying confidence interval of travel time on arterials is forecasted using an autoregressive integrated moving average and generalized autoregressive co... To improve the forecasting reliability of travel time, the time-varying confidence interval of travel time on arterials is forecasted using an autoregressive integrated moving average and generalized autoregressive conditional heteroskedasticity (ARIMA-GARCH) model. In which, the ARIMA model is used as the mean equation of the GARCH model to model the travel time levels and the GARCH model is used to model the conditional variances of travel time. The proposed method is validated and evaluated using actual traffic flow data collected from the traffic monitoring system of Kunshan city. The evaluation results show that, compared with the conventional ARIMA model, the proposed model cannot significantly improve the forecasting performance of travel time levels but has advantage in travel time volatility forecasting. The proposed model can well capture the travel time heteroskedasticity and forecast the time-varying confidence intervals of travel time which can better reflect the volatility of observed travel times than the fixed confidence interval provided by the ARIMA model. 展开更多
关键词 confidence interval forecasting travel time autoregressive integrated moving average and generalized autoregressive conditional heteroskedasticity ARIMA-GARCH) conditional variance reliability
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Static softening behaviors of 7055 alloy during the interval time of multi-pass hot compression 被引量:6
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作者 Liang-Ming Yan Jian Shen +1 位作者 Jun-Peng Li Bai-Ping Mao 《Rare Metals》 SCIE EI CAS CSCD 2013年第3期241-246,共6页
Multipass plain strain compression test of 7055 alloy was carried out on Gleeble 1500D thermomechanical simulator to study the effect of interval time on static softening behavior between two passes. Microstructural f... Multipass plain strain compression test of 7055 alloy was carried out on Gleeble 1500D thermomechanical simulator to study the effect of interval time on static softening behavior between two passes. Microstructural features of the alloy deformed with delay times varying from 0 to 180 s after achieving a reduction of ,-~52 % in the 13 stages was investigated through TEM and EBSD observations. The 14th pass of peak stresses after different delay times were gained. The peak stress decreases with the interstage delay time increasing, but the decreasing trend is gradually slower. Static recovery, metadynamic recrystallization, and/or static recrystallization can be found in the alloy during two passes. The recovery and recrystallization degree increases with longer interstage delay time. The static recovery is the main softening mechanism. Subgrain coalescence and subgrain growth together with particle-stimulated nucleation are the main nucleation mechanisms for static recrystallization. 展开更多
关键词 7055 aluminum alloy Hot compression Microstructure interval time
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Association between tear film break up time and blink interval in visual display terminal users 被引量:6
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作者 Miki Uchino Motoko Kawashima +2 位作者 Yuichi Uchino Kazuo Tsubota Norihiko Yokoi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第10期1691-1697,共7页
AIM:To investigate the association between tear film break up time(TBUT)and blinking interval in visual display terminal(VDT)users.METHODS:Nine hundred and thirty VDT users underwent dry eye testing,and function... AIM:To investigate the association between tear film break up time(TBUT)and blinking interval in visual display terminal(VDT)users.METHODS:Nine hundred and thirty VDT users underwent dry eye testing,and functional visual acuity(FVA)test.The blinking interval during FVA was compared with TBUT.Subjects with longer blinking interval than TBUT were considered as unstable tear film.Logistic regression analysis revealed the risk factors for unstable tear group.RESULTS:Among 930 workers,858 subjects(92.3%)participated in this study.Almost 80% of the subjects were categorized into the unstable tear group.Unstable tear group has significantly lower Schirmer values and TBUT(17.5±11.6 vs 21.1±11.5 mm,3.7±2.6 vs 5.7±2.7s,both P〈0.001).There were no significant differences in epithelial staining or severity of symptoms.Logistic regression showed that over 40y was a risk for being unstable tear group[odds ratio(OR)=1.53;95%confidence interval(CI)=1.06-2.20].Contact lens use was protective factor for being in the unstable tear group(OR=0.37;95%CI=0.26-0.53).CONCLUSION:Subjects with shorter TBUT than blinking interval are prevalent among VDT users.Subjects over the age of 40 shows an increased risk for unstable tear film. 展开更多
关键词 dry eye disease blink interval tear film break up time visual display terminal use
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THE INFLUENCE OF ELECTRO-ACUPUNCTURE AT NEIGUAN AND FIVE SHU POINTS OF TWELVE REGULAR MERIDIANS AT DIFFERENT TIME ON SYSTOLIC TIME INTERVAL OF NORMAL YOUNG ADULTS 被引量:2
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作者 Li Lei, Chen Hanping, Xi Yongjiang, Gu JieShanghai University of TCM, Shanghai 200032, China 《World Journal of Acupuncture-Moxibustion》 1994年第1期40-45,共6页
The influence of electro-acupuncture at Neiguan (PC 6)and five shu points of twelve regular meridians at different time on systolic time interval (ST I) of normal young adultswere studied with 6×6 Latin square de... The influence of electro-acupuncture at Neiguan (PC 6)and five shu points of twelve regular meridians at different time on systolic time interval (ST I) of normal young adultswere studied with 6×6 Latin square design in this work.In 12 groups according to 12 regular merldlans,the STIs were measured respectively just before and after electro-acupuncture on Neiguan andfive shu points at 00:00,04:00,08:00,12:00,16:00 and 20:00 of a day.It was found thatexcept the PEPI and PEPI/LVETI ratio among Shenmen(HT 7),Shaochong(HT 9)and Neiguan,Guanchong(TE)and Yemen(TE 2)points,the effects of electro-acupuncture at Neiguan pointand five shu points of twelve regular meridians on the indices of STI of normal young adults wereshowing no slgnificant differences.There also was no difference in different sex.But the indices ofSTI were changed when electroacupuncture on the different points of different meridians at differenttime. 展开更多
关键词 ELECTRO-ACUPUNCTURE NEIGUAN Five Shu points SYSTOLIC time interval
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Influences of different time intervals between loop electrosurgical excision and abdominal hysterectomy or radical hysterectomy on postoperative complications: a retrospective analysis 被引量:5
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作者 Qu Haina Zhang Yan Zhang Junjie Hui Ning Xu Mingjuan 《Journal of Medical Colleges of PLA(China)》 CAS 2010年第1期38-43,共6页
Objective: To study the influences of different time intervals between loop electrosurgical excision (LEEP) and abdominal hysterectomy or radical hysterectomy on postoperative complications. Methods: Sixty-eight p... Objective: To study the influences of different time intervals between loop electrosurgical excision (LEEP) and abdominal hysterectomy or radical hysterectomy on postoperative complications. Methods: Sixty-eight patients, who received subsequent abdominal hysterectomy or radical hysterectomy after LEEP due to C1N III and cervical cancer (IA1, IA2 and IB1), were included in the present study. The hospital and clinic records of these patients were reviewed. The patients were divided into three groups according to the time intervals between LEEP and hysterectomy or radical hysterectomy: group l(within 48 h), group 2 (between 48 h to 6 weeks), and group 3(〉 6 weeks ).Results: General characteristics of patients, including the mean age, delivery history, BMI, menopausal status, clinical stage and HPV infection, were comparable between patients of different groups. There were no significant differences in the mean transfusion amount, posthysterectomy hospital stay or operation time between different groups. The frequencies and spectrum of complications were not significantly affected by the time interval between LEEP and hysterectomy or radical hysterectomy. Conclusion: It is concluded that whenever the LEEP is done, the operation including hysterectomy or radical hysterectomy can be conducted at any time as it is necessary for the patients. 展开更多
关键词 LEEP HYSTERECTOMY Radical hysterectomy time interval CIN III Early cervical cancer
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Variational Inference Based Kernel Dynamic Bayesian Networks for Construction of Prediction Intervals for Industrial Time Series With Incomplete Input 被引量:2
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作者 Long Chen Linqing Wang +2 位作者 Zhongyang Han Jun Zhao Wei Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第5期1437-1445,共9页
Prediction intervals(PIs)for industrial time series can provide useful guidance for workers.Given that the failure of industrial sensors may cause the missing point in inputs,the existing kernel dynamic Bayesian netwo... Prediction intervals(PIs)for industrial time series can provide useful guidance for workers.Given that the failure of industrial sensors may cause the missing point in inputs,the existing kernel dynamic Bayesian networks(KDBN),serving as an effective method for PIs construction,suffer from high computational load using the stochastic algorithm for inference.This study proposes a variational inference method for the KDBN for the purpose of fast inference,which avoids the timeconsuming stochastic sampling.The proposed algorithm contains two stages.The first stage involves the inference of the missing inputs by using a local linearization based variational inference,and based on the computed posterior distributions over the missing inputs the second stage sees a Gaussian approximation for probability over the nodes in future time slices.To verify the effectiveness of the proposed method,a synthetic dataset and a practical dataset of generation flow of blast furnace gas(BFG)are employed with different ratios of missing inputs.The experimental results indicate that the proposed method can provide reliable PIs for the generation flow of BFG and it exhibits shorter computing time than the stochastic based one. 展开更多
关键词 Industrial time series kernel dynamic Bayesian networks(KDBN) prediction intervals(PIs) variational inference
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Vitreoretinal surgeons'experience and time interval from pars-plana vitrectomy to cataract extraction 被引量:1
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作者 Yan-Xin Xu Liang-Ping Liu +4 位作者 Jian-Bing Li Huan-Huan Cheng Min Hou Lin Lu Ming-Xing Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第1期120-126,共7页
AIM:To identify the association of the vitreoretinal surgeons'experience with the time interval between parsplana vitrectomy(PPV)and cataract extraction(CE).METHODS:Eyes with prior PPV and following CE were includ... AIM:To identify the association of the vitreoretinal surgeons'experience with the time interval between parsplana vitrectomy(PPV)and cataract extraction(CE).METHODS:Eyes with prior PPV and following CE were included in this retrospective cohort study.The years of practice and the annual case volume were used to describe the surgeons'experience.Multivariable linear regression analysis was used to investigate the relationship between surgeons'experience and the time interval adjusted for the patients age,gender,intraocular tamponade,and case complexity.RESULTS:Of 132430 eyes,1445 eyes were included in this study.In multivariable linear regression analysis,cases performed by surgeons with>20 practice years had longer time intervals compared with surgeons with<10 practice years after adjusted for other variables(β=0.329,95%CI:0.113 to 0.549,P=0.003).No difference in time interval was detected for comparing the lowest with the highest volume groups(β=0.089,95%CI:-0.164 to 0.343,P=0.343).The surgeons'practice years were not directly with the volume.For complicated surgery,the higherpractice-year surgeons had longer time interval than lowerpractice-year surgeons.CONCLUSION:The time intervals from PPV to CE is longer in higher-practice-year surgeons.The surgeons'practice years may have a greater effect on the time interval than annual case volume in high-complexity cases.Matching the complexity of vitreoretinal diseases with the surgeons'practice year should be considered. 展开更多
关键词 pars-plana vitrectomy cataract time interval EXPERIENCE annual case volume
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Time variant multi-objective linear fractional interval-valued transportation problem 被引量:1
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作者 Dharmadas Mardanya Sankar Kumar Roy 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第1期111-130,共20页
This paper studies a time-variant multi-objective linear fractional transportation problem. In reality, transported goods should reach in destinations within a specific time. Considering the importance of time, a time... This paper studies a time-variant multi-objective linear fractional transportation problem. In reality, transported goods should reach in destinations within a specific time. Considering the importance of time, a time-variant multi-objective linear fractional transportation problem is formulated here. We take into account the parameters as cost, supply and demand are interval valued that involved in the proposed model, so we treat the model as a multi-objective linear fractional interval transportation problem. To solve the formulated model, we first convert it into a deterministic form using a new transformation technique and then apply fuzzy programming to solve it. The applicability of our proposed method is shown by considering two numerical examples. At last, conclusions and future research directions regarding our study is included. 展开更多
关键词 fractional transportation problem multi-objective optimization interval number time variant parameter fuzzy programming Pareto optimal solution
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Study on conveyor natural frequency and time intervalfor switching off resistances 被引量:3
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作者 李光布 杨汝清 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第6期685-689,共5页
A conveyor belt driven by wound rotor motors produces dynamic tension, velocity and accelerationduring starting. The terrible situation (such as resonance) in dynamic analysis and design is that system naturalfrequenc... A conveyor belt driven by wound rotor motors produces dynamic tension, velocity and accelerationduring starting. The terrible situation (such as resonance) in dynamic analysis and design is that system naturalfrequencies are equal to those for switching off electric resistances. This paper analyzes and determines systemnatural frequencies based on a modeling method of receptances with the analysis of sub-systems model and of theprinciple of their addition and conveyor loop closure. It also puts forward to calculate the time interval for switching off electric resistances. The starting of one conveyor is simulated by lumped-mass-spring-model software tofurther illustrate the influence of time interval for switching off electric resistances on conveyor dynamic behavior. Two methods are also compared. The receptance model is proved to be an excellent alternative. 展开更多
关键词 natural frequency receptance model switching-off time interval conveyor dynamic behavior
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Delay-dependent Robust Stability for Uncertain Stochastic Systems with Interval Time-varying Delay 被引量:5
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作者 ZHANG Yan HE Yong WU Min 《自动化学报》 EI CSCD 北大核心 2009年第5期577-582,共6页
关键词 随机系统 稳定性 自动化 分析
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A real-time performance improvement method for composite time scale
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作者 Fangmin Wang Wenlin Li +4 位作者 Hongfei Dai Chunyi Li Jianhua Zhou Shenhui Xue Bo Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期350-357,共8页
The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern society.The improvement of CTS’s real-time performance will improve its stability,which strengths related applications’perfo... The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern society.The improvement of CTS’s real-time performance will improve its stability,which strengths related applications’performance.Aiming at this goal,a method achieved by determining the optimal calculation interval and accelerating adjustment stage is proposed in this paper.The determinants of the CTS’s calculation interval(characteristics of the clock ensemble,the measurement noise,the time and frequency synchronization system’s noise and the auxiliary output generator noise floor)are studied and the optimal calculation interval is obtained.We also investigate the effect of ensemble algorithm’s initial parameters on the CTS’s adjustment stage.A strategy to get the reasonable initial parameters of ensemble algorithm is designed.The results show that the adjustment stage can be finished rapidly or even can be shorten to zero with reasonable initial parameters.On this basis,we experimentally generate a distributed CTS with a calculation interval of 500 s and its stability outperforms those of the member clocks when the averaging time is longer than1700 s.The experimental result proves that the CTS’s real-time performance is significantly improved. 展开更多
关键词 composite time scale real-time performance calculation interval adjustment stage
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Passivity analysis for uncertain stochastic neural networks with discrete interval and distributed time-varying delays 被引量:3
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作者 P.Balasubramaniam G.Nagamani 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期688-697,共10页
The problem of passivity analysis is investigated for uncertain stochastic neural networks with discrete interval and distributed time-varying delays.The parameter uncertainties are assumed to be norm bounded and the ... The problem of passivity analysis is investigated for uncertain stochastic neural networks with discrete interval and distributed time-varying delays.The parameter uncertainties are assumed to be norm bounded and the delay is assumed to be time-varying and belongs to a given interval,which means that the lower and upper bounds of interval time-varying delays are available.By constructing proper Lyapunov-Krasovskii functional and employing a combination of the free-weighting matrix method and stochastic analysis technique,new delay-dependent passivity conditions are derived in terms of linear matrix inequalities(LMIs).Finally,numerical examples are given to show the less conservatism of the proposed conditions. 展开更多
关键词 linear matrix inequality(LMI) stochastic neural network PASSIVITY interval time-varying delay Lyapunov method.
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On designing memory state feedback controller for linear systems with interval time-varying delay 被引量:2
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作者 Xiangpeng XIE Huaguang ZHANG Tao LIU 《控制理论与应用(英文版)》 EI 2010年第4期479-484,共6页
This paper is concerned with the design of a memory state feedback controller for linear systems with interval time-varying delays.The time delay is assumed to be a time-varying continuous function belonging to a give... This paper is concerned with the design of a memory state feedback controller for linear systems with interval time-varying delays.The time delay is assumed to be a time-varying continuous function belonging to a given interval,which means that the lower and upper bounds of time-varying delay are available.First,a less conservative delay-range-dependent stability criteria is proposed by using a new interval fraction method.In the process of controller synthesis,the history information of system is considered in the controller design by introducing the lower delay state.Moreover,the usual memoryless state feedback controller for the underlying systems could be considered as a special case of the memory case.Finally,two numerical examples are given to show the effectiveness of the proposed method. 展开更多
关键词 DELAY-RANGE-DEPENDENT interval time-varying delay Linear matrix inequalities (LMIs) Relaxed stabilization conditions
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Timed automata for metric interval temporal logic formulae in prototype verification system
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作者 许庆国 缪淮扣 《Journal of Shanghai University(English Edition)》 CAS 2008年第4期339-346,共8页
Based on analysis of the syntax structure and semantics model of the metric interval temporal logic (MITL) formulas, it is shown how to transform a formula written in the real-time temporal logic MITL formula into a... Based on analysis of the syntax structure and semantics model of the metric interval temporal logic (MITL) formulas, it is shown how to transform a formula written in the real-time temporal logic MITL formula into a fair timed automaton (TA) that recognizes its satisfying models with prototype verification system (PVS) in this paper. Both the tabular construction's principles and the PVS implementation details are given for the different type of MITL formula according to the corresponding semantics interpretations. After this transformation procedure, specifications expressed with MITL formula can be verified formally in the timed automata framework developed previously. 展开更多
关键词 real-time system metric interval temporal logic (MITL) timed automata (TA) prototype verificationsystem (PVS)
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An On-Line Modeling Based Kalman Filtering Process for Time-Interval-Variable Sequences with Application to Astronomic Surveying
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作者 韩建国 孙才红 李彦琴 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第2期52-56,共5页
The problem of variable sampling time interval which appears in application of Kalman Filtering is analyzed and the corresponding filtering process with or without present transition matrix is suggested, then an appli... The problem of variable sampling time interval which appears in application of Kalman Filtering is analyzed and the corresponding filtering process with or without present transition matrix is suggested, then an application experiment for astronomical surveying is introduced. In this process, the known stochastically variable sampling time intervals play the roles as deterministic input sequences of the state-space description, and the corresponding matrix and (if needed) state transition matrix can be established by performing real-time and structure-linear system identification. 展开更多
关键词 Kalman filtering Variable sampling time interval Real-time and structure-linear system identification.
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Discussion of the Horizontal Intensity of Late Quaternary Fault Activity Along the Tianjingshan Fault Zone in Different Time Intervals and Fault Segments 被引量:1
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作者 Chai Chizhang,Zhang Weiqi,and Jiao DechengSeismological Bureau of Ningxia Hui Autonomous Region,Yinchuan 750001,China 《Earthquake Research in China》 1997年第3期25-32,共8页
By computing and classifying the data of gully offset obtained from field surveys along the Tianjingshan fault zone and estimating the ages of three types of gullies,the strike-slip rates along the fault zone are disc... By computing and classifying the data of gully offset obtained from field surveys along the Tianjingshan fault zone and estimating the ages of three types of gullies,the strike-slip rates along the fault zone are discussed in different time intervals and fault segments.The results suggest that the intensity of activity along the fault zone is not strong,but the differences between different time intervals and fault segments since the late Pleistocene have been obvious.The average rates range from 0.23 mm/a to 1.62 mm/a.The largest average rate is 1.40 mm/a,which occurred in the early and middle of late Pleistocene along the western segment of the fault zone.Since the late stage of the late Pleistocene,the center of faulting activity of the fault zone has shifted to the middle segment,and the average slip rates range have changed from 1.30 mm/a to 1.63 mm/a. 展开更多
关键词 Discussion of the Horizontal Intensity of Late Quaternary Fault Activity Along the Tianjingshan Fault Zone in Different time intervals and Fault Segments Activity
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TIME INTERVAL APPROACH TO THE PULSED NEUTRON LOGGING METHOD
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作者 赵经武 苏为宁 《Nuclear Science and Techniques》 SCIE CAS CSCD 1994年第2期118-123,共6页
The time interval of neibouring neutrons emitted from a steady state neutron source can be treated as that from a time-dependent neutron source. In the rockspace, the neutron flux is given by the neutron diffusion equ... The time interval of neibouring neutrons emitted from a steady state neutron source can be treated as that from a time-dependent neutron source. In the rockspace, the neutron flux is given by the neutron diffusion equation and is composedof an infinite number of 'modes'. Each 'mode' is composed of two die-away curves.The delay action has been discussed and used to measure the time interval withonly one detector in the experimellt. Nuclear reactions with the time distributiondue to different types of radiations observed in the neutron well-logging methods arepresented with a view to getting the rock nuclear parameters from the time intervaltechnique. 展开更多
关键词 time interval Steady state neutron source Delay action Neutronlogging method
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Time Intervals of the Electron Transitions between the Energy States in the Hydrogen Atom Calculated in a Non-Probabilistic Way 被引量:1
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2019年第13期1522-1531,共10页
Definitions of the mechanical parameters entering the Bohr model of the hydrogen atom allowed us to calculate the time intervals connected with the electron transitions between the nearest-neighbouring energy levels i... Definitions of the mechanical parameters entering the Bohr model of the hydrogen atom allowed us to calculate the time intervals connected with the electron transitions between the nearest-neighbouring energy levels in the atom. This is done in a strictly non-probabilistic way. The time results are compared with those derived earlier on the basis of the classical Joule-Lenz law for the energy emission adapted to the case of the electron transfer in the quantum systems. A similar formalism has been next applied to the harmonic oscillator and a particle moving in the one-dimensional potential box. 展开更多
关键词 Spectrum of the Hydrogen Atom time intervals of the Electron Transitions
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