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Derivation of Simplified Models of Plan View Pattern Control Function for Plate Mill 被引量:7
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作者 JIAO Zhi-jie HU Xian-lei ZHAO Zhong LIU Xiang-hua WANG Guo-dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2007年第4期20-23,共4页
The plan view pattern control theoretical models were simplified. Under the condition of constant volume for the plan view pattern compensation, the relation between the thickness and the length can be simplified to t... The plan view pattern control theoretical models were simplified. Under the condition of constant volume for the plan view pattern compensation, the relation between the thickness and the length can be simplified to the linearity in the segment for the plan view pattern control function. The compensation volume can be dispersed for easy calculation. By comparing the model calculation result with the actual result, it was concluded that the simplified model can be used for the online control process. 展开更多
关键词 plan view pattern control theoretical model simplified model
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Width Compensation and Correction for the Plan View Pattern Control Function on Plate Mill 被引量:5
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作者 Zhi-Jie Jiao Chun-Yu He +1 位作者 Zhong Zhao Jing-Guo Ding 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第5期31-35,共5页
Research works on width compensation and correction were carried out in order to eliminate the effects of the PVPC ( plan view pattern control) on width accuracy of plate mill. The thickness correction calculation f... Research works on width compensation and correction were carried out in order to eliminate the effects of the PVPC ( plan view pattern control) on width accuracy of plate mill. The thickness correction calculation formula was derived for compensation the width deviation caused by PVPC function, and the formula is unified under the thinning and thickening conditions. In order to improve the width calculation accuracy, width spread calculation process was modified with dividing one large reduction pass to several small reduction calculation steps. The thickness wedge was simplified to rectangle based on the volume constant principle, and the width spread model for PVPC was constructed. The width compensation and correction for the PVPC functions are used for the online control process, and the Product dimension accuracy is improved. With the decrease of Crop losses, the Droduct yield was increased with 0. 2%. 展开更多
关键词 Lplate mill plan view pattern control width correction and compensation width spread model
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Calculation of Taper Rolling Time in Plan View Pattern Control Process 被引量:3
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作者 JIAO Zhi-jie HU Xian-lei ZHAO Zhong LIU Xiang-hua WANG Guo-dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第5期1-3,共3页
The forward slip model with adhesion was used to derive the formula of calculating taper rolling time. The relation between the rolling time and the taper length and the relation between the rolling time and the taper... The forward slip model with adhesion was used to derive the formula of calculating taper rolling time. The relation between the rolling time and the taper length and the relation between the rolling time and the taper thickness can be obtained. The numerical solution for this formula was used on site. According to the simulation result, the roll gap value should be changed linearly with rolling time. 展开更多
关键词 plan view pattern control forward slip model TAPER time calculation
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Automated Identification of Basic Control Charts Patterns Using Neural Networks 被引量:5
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作者 Ahmed Shaban Mohammed Shalaby +1 位作者 Ehab Abdelhafiez Ashraf S. Youssef 《Journal of Software Engineering and Applications》 2010年第3期208-220,共13页
The identification of control chart patterns is very important in statistical process control. Control chart patterns are categorized as natural and unnatural. The presence of unnatural patterns means that a process i... The identification of control chart patterns is very important in statistical process control. Control chart patterns are categorized as natural and unnatural. The presence of unnatural patterns means that a process is out of statistical control and there are assignable causes for process variation that should be investigated. This paper proposes an artificial neural network algorithm to identify the three basic control chart patterns;natural, shift, and trend. This identification is in addition to the traditional statistical detection of runs in data, since runs are one of the out of control situations. It is assumed that a process starts as a natural pattern and then may undergo only one out of control pattern at a time. The performance of the proposed algorithm was evaluated by measuring the probability of success in identifying the three basic patterns accurately, and comparing these results with previous research work. The comparison showed that the proposed algorithm realized better identification than others. 展开更多
关键词 Artificial Neural Networks (ANN) control Charts control Charts patternS Statistical Process control (SPC) Natural pattern SHIFT pattern TREND pattern
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Pattern control for large-scale spacecraft swarms in elliptic orbits via density fields 被引量:3
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作者 Chihang YANG Hao ZHANG Weida FU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第3期367-379,共13页
Space swarms,enabled by the miniaturization of spacecraft,have the potential capability to lower costs,increase efficiencies,and broaden the horizons of space missions.The formation control problem of large-scale spac... Space swarms,enabled by the miniaturization of spacecraft,have the potential capability to lower costs,increase efficiencies,and broaden the horizons of space missions.The formation control problem of large-scale spacecraft swarms flying around an elliptic orbit is considered.The objective is to drive the entire formation to produce a specified spatial pattern.The relative motion between agents becomes complicated as the number of agents increases.Hence,a density-based method is adopted,which concerns the density evolution of the entire swarm instead of the trajectories of individuals.The density-based method manipulates the density evolution with Partial Differential Equations(PDEs).This density-based control in this work has two aspects,global pattern control of the whole swarm and local collision-avoidance between nearby agents.The global behavior of the swarm is driven via designing velocity fields.For each spacecraft,the Q-guidance steering law is adopted to track the desired velocity with accelerations in a distributed manner.However,the final stable velocity field is required to be zero in the classical density-based approach,which appears as an obstacle from the viewpoint of astrodynamics since the periodic relative motion is always time-varying.To solve this issue,a novel transformation is constructed based on the periodic solutions of Tschauner-Hempel(TH)equations.The relative motion in Cartesian coordinates is then transformed into a new coordinate system,which permits zero-velocity in a stable configuration.The local behavior of the swarm,such as achieving collision avoidance,is achieved via a carefully-designed local density estimation algorithm.Numerical simulations are provided to demonstrate the performance of this approach. 展开更多
关键词 Collision avoidance Density-based feedback control Distributed control Formation flight Large-scale swarms pattern generation PDE-based control TH equation
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Control strategy of central pattern generator gait movement under condition of attention selection 被引量:2
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作者 Wei WANG Rubin WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第7期957-966,共10页
As a typical rhythmic movement, human being's rhythmic gait movement can be generated by a central pattern generator (CPG) located in a spinal cord by self- oscillation. Some kinds of gait movements are caused by g... As a typical rhythmic movement, human being's rhythmic gait movement can be generated by a central pattern generator (CPG) located in a spinal cord by self- oscillation. Some kinds of gait movements are caused by gait frequency and amplitude variances. As an important property of human being's motion vision, the attention selection mechanism plays a vital part in the regulation of gait movement. In this paper, the CPG model is amended under the condition of attention selection on the theoretical basis of Matsuoka neural oscillators. Regulation of attention selection signal for the CPG model parameters and structure is studied, which consequentially causes the frequency and amplitude changes of gait movement output. Further, the control strategy of the CPG model gait movement under the condition of attention selection is discussed, showing that the attention selection model can regulate the output model of CPG gait movement in three different ways. The realization of regulation on the gait movement frequency and amplitude shows a variety of regulation on the CPG gait movement made by attention selection and enriches the controllability of CPG gait movement, which demonstrates potential influence in engineering applications. 展开更多
关键词 gait movement attention selection central pattern generator (CPG) movement control strategy
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Reservoirs Patterns and Key Controlling Factors of the Lenghu Oil & Gas Field in the Qaidam Basin, Northwestern China 被引量:1
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作者 Wengang He Ehsan Barzgar +1 位作者 Weiping Feng Liang Huang 《Journal of Earth Science》 SCIE CAS CSCD 2021年第4期1011-1021,共11页
The Lenghu area is one of the most crucial tectonic belts for oil and gas exploration in the Qaidam Basin.However,reservoir distribution and the factors controlling petroleum accumulation in this area have not been st... The Lenghu area is one of the most crucial tectonic belts for oil and gas exploration in the Qaidam Basin.However,reservoir distribution and the factors controlling petroleum accumulation in this area have not been studied in detail.In this paper,the structural characteristics and controlling factors of oil and gas accumulation in the Lenghu belt are investigated based on seismic profiles combined with drilling logs and microphotographs data.Results indicate that the Lenghu belt has thick source rocks and has preserved hydrocarbon generation conditions.Moreover,structural characteristics and lithology are the key factors controlling the reservoir distribution.The production of oil and gas layers are mainly distributed in high structural points and weak stress zones.The fracture zones and the weak stress zones are the potential places for the distribution of oil and gas reservoirs. 展开更多
关键词 Lenghu belt reservoir patterns controlling factor potential distribution zones
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Safer Design and Less Cost Operation for Low-Traffic Long-Road Illumination Using Control System Based on Pattern Recognition Technique 被引量:1
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作者 Muhammad M. A. S. Mahmoud Leyla Muradkhanli 《Intelligent Control and Automation》 2020年第3期47-62,共16页
The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street ligh... The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street lighting system at night for the entire road, or inexpensive design that sacrifices the safety, relying on using vehicles lighting, to eliminate the problem of high cost energy consumption during the night operation of the road. By taking into account both of these factors, smart lighting automation system is proposed using Pattern Recognition Technique applied on vehicle number-plates. In this proposal, the road is sectionalized into zones, and based on smart Pattern Recognition Technique, the control system of the road lighting illuminates only the zone that the vehicles pass through. Economic analysis is provided in this paper to support the value of using this design of lighting control system. 展开更多
关键词 Road Lighting control Road Lighting Automation Vehicle Number-Plate pattern Recognition Smart Grid Power Management Low Traffic Roads Image Processing
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An Intelligent Single Adaptive Neuron Controller Based on Pattern Recognition
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作者 李巍 李士勇 +1 位作者 郎力 赵长安 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第4期31-33,共3页
The trajectory of the controlled system in phase space has been investigated, and different learning methods are applied to the single adaptive neuron controller according to the pattem of the control system. The adva... The trajectory of the controlled system in phase space has been investigated, and different learning methods are applied to the single adaptive neuron controller according to the pattem of the control system. The advantage of the controller presented has been shown by simulation of a satellite attitude stability control system. 展开更多
关键词 SINGLE adaptive NEURON controlLER INTELLIGENT control pattern recognition phase space
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A hybrid stochastic fractal search and pattern search technique based cascade PI-PD controller for automatic generation control of multi-source power systems in presence of plug in electric vehicles 被引量:1
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作者 Sasmita Padhy Sidhartha Panda 《CAAI Transactions on Intelligence Technology》 2017年第1期12-25,共14页
A hybrid Stochastic Fractal Search plus Pattern Search (hSFS-PS) based cascade PI-PD controller is suggested in this paper for Automatic Generation Control (AGC) of thermal, hydro and gas power unit based power sy... A hybrid Stochastic Fractal Search plus Pattern Search (hSFS-PS) based cascade PI-PD controller is suggested in this paper for Automatic Generation Control (AGC) of thermal, hydro and gas power unit based power systems in presence of Plug in Electric Vehicles (PEV). Firstly, a single area multi-source power system consisting of thermal hydro and gas power plants is considered and parameters of Integral (I) controller is optimized by Stochastic FractaI Search (SFS) algorithm. The superiority of SFS algorithm over some recently proposed approaches such as optimal control, differential evolution and teaching learning based optimization techniques is demonstrated by comparing simulation results for the identical power system. To improve the system performance further, Pattern Search (PS) is subsequently employed. The study is further extended for different controllers like PI, PID, and cascaded PI-PD controller and the superiority of cascade PI-PD controller over conventional controllers is demonstrated. Then, cascade PI- PD controller parameters of AGC searched using the proposed hSFS-PS algorithm in presence of plug in electric vehicles. The study is also extended to an interconnected power system. It is seen from the comparative analysis that hSFS-PS tuned PI-PD controller in single and multi-area with multi sources improves the system frequency stability in complicated situations. Lastly, a three area interconnected system with PEVs with dissimilar cascade PI-PD controller in each area is considered and proposed hSFS- PS algorithm is used to tune the controller parameters in presence of nonlinearities like rate constraint of units, dead zone of governor and communication delay. 展开更多
关键词 Automatic generation control Cascade PI-PD controller Stochastic fractal search pattern search Plug in electric vehicles
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Nutrient patterns and risk of cataract:a case-control study 被引量:1
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作者 Fatemeh Sedaghat Matin Ghanavati +3 位作者 Parisa Nezhad Hajian Sara Hajishirazi Mehdi Ehteshami Bahram Rashidkhani 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期586-592,共7页
AIM:To assess the relation between nutrient patterns and cataract risk.METHODS:This is a hospital-based case-control study with 97 cataract patients and 198 matched controls.Dietary consumption was collected through... AIM:To assess the relation between nutrient patterns and cataract risk.METHODS:This is a hospital-based case-control study with 97 cataract patients and 198 matched controls.Dietary consumption was collected through a valid food frequency questionnaire(FFQ).Nutrient patterns were detected by applying factor analysis.Unconditional logistic regression models were used to estimate odds ratio(ORs) and 95%CIs.RESULTS:We extracted 5 main nutrient patterns.Factor 1 included niacin,thiamin,carbohydrates,protein,zinc,vitamin B6 and sodium(sodium pattern).Factor 2 was characterized by oleic acid,monounsaturated fats,polyunsaturated fats,linoleic acid,trans fatty acid,linolenic acid,vitamin E and saturated fats(fatty acid pattern).The third factor represented high intake of vitamin B12,vitamin D,cholesterol and calcium(mixed pattern).The 4^(th) pattern was high in intake of beta and alpha carotene,vitamin A and vitamin C(antioxidant pattern).Finally,the 5^(th) pattern loaded heavily on docosahexaenoic acid(DHA) and eicosapentaenoic acid(EPA)(omega-3 pattern).In crude and multivariate analysis,the sodium pattern was associated with increased risk of cataract(OR=1.97,95%CI:1.09-3.96).The fatty acid pattern elevated the risk of cataract(OR=1.94,95%CI:1.1-3.86).Antioxidant pattern was associated with a significant 79% reduced risk(2^(nd) category compared with the 1st).Omega-3 pattern was significantly negatively associated with risk of cataract(P=0.04).CONCLUSION:These findings imply that nutrient patterns reflecting a combined consumption of nutrients might be important in the etiology of cataract.Additional studies with more efficient designs are warranted to confirm our findings. 展开更多
关键词 nutrient patterns CATARACT case-control study
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Distribution Patterns of Remaining Hydrocarbons Controlled by Reservoir Architecture of Distributary Channel with Different Channel Style: S2 Formation of Songliao Basin, China
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作者 LI Weiqiang YIN Taiju +1 位作者 ZHAO Lun ZHAO Liangdong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期129-130,共2页
1 Introduction Reservoir architecture analysis of distributary channel of Daqing oilfield has drawn consistent interest among development geologists and petroleum engineers over the last decade(Lv et al.,1999;Zhou et ... 1 Introduction Reservoir architecture analysis of distributary channel of Daqing oilfield has drawn consistent interest among development geologists and petroleum engineers over the last decade(Lv et al.,1999;Zhou et al.,2008;Zhang et 展开更多
关键词 China Distribution patterns of Remaining Hydrocarbons controlled by Reservoir Architecture of Distributary Channel with Different Channel Style
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Pulling apart patterns and fabric fingerprinting
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《China Textile》 2025年第3期54-55,共2页
A leading position in the areas of testing,instrumentation and machine control has been established by members of the British Textile Machinery Association(BTMA)and a number of new developments in these fields will be... A leading position in the areas of testing,instrumentation and machine control has been established by members of the British Textile Machinery Association(BTMA)and a number of new developments in these fields will be showcased at this year’s ITMA Asia+CITME exhibition,which takes place in Singapore from October 28-31.“Many of our members are currently developing new technologies,either in-house or increasingly through joint projects,and there will be much to reveal by the time of ITMA Asia in Singapore,”says BTMA CEO Jason Kent.“Some of the most recent developments are really going beyond what has previously been possible.” 展开更多
关键词 fabric fingerprinting technologies machine control patternS testing btma itma asia citme instrumentation
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An Improved Chicken Swarm Optimization Techniques Based on Cultural Algorithm Operators for Biometric Access Control
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作者 Jonathan Ponmile Oguntoye Sunday Adeola Ajagbe +4 位作者 Oluyinka Titilayo Adedeji Olufemi Olayanju Awodoye Abigail Bola Adetunji Elijah Olusayo Omidiora Matthew Olusegun Adigun 《Computers, Materials & Continua》 2025年第9期5713-5732,共20页
This study proposes a system for biometric access control utilising the improved Cultural Chicken Swarm Optimization(CCSO)technique.This approach mitigates the limitations of conventional Chicken Swarm Optimization(CS... This study proposes a system for biometric access control utilising the improved Cultural Chicken Swarm Optimization(CCSO)technique.This approach mitigates the limitations of conventional Chicken Swarm Optimization(CSO),especially in dealing with larger dimensions due to diversity loss during solution space exploration.Our experimentation involved 600 sample images encompassing facial,iris,and fingerprint data,collected from 200 students at Ladoke Akintola University of Technology(LAUTECH),Ogbomoso.The results demonstrate the remarkable effectiveness of CCSO,yielding accuracy rates of 90.42%,91.67%,and 91.25%within 54.77,27.35,and 113.92 s for facial,fingerprint,and iris biometrics,respectively.These outcomes significantly outperform those achieved by the conventional CSO technique,which produced accuracy rates of 82.92%,86.25%,and 84.58%at 92.57,63.96,and 163.94 s for the same biometric modalities.The study’s findings reveal that CCSO,through its integration of Cultural Algorithm(CA)Operators into CSO,not only enhances algorithm performance,exhibiting computational efficiency and superior accuracy,but also carries broader implications beyond biometric systems.This innovation offers practical benefits in terms of security enhancement,operational efficiency,and adaptability across diverse user populations,shaping more effective and resource-efficient access control systems with real-world applicability. 展开更多
关键词 Access control biometric technology chicken swarm optimization cultural algorithm pattern recognition
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Review of Control Techniques for Dual Three-phase PMSM Drives with Low Carrier Ratios
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作者 Minrui Gu Zheng Wang +3 位作者 Ming Cheng Weifeng Su Linyue Shang Po Liu 《CES Transactions on Electrical Machines and Systems》 2025年第2期177-188,共12页
The dual three-phase PMSM(DTP-PMSM)drives have received wide attention at high-power high-efficiency applications due to their merits of high output current ability and copper-loss-free field excitation.Meanwhile,the ... The dual three-phase PMSM(DTP-PMSM)drives have received wide attention at high-power high-efficiency applications due to their merits of high output current ability and copper-loss-free field excitation.Meanwhile,the DTPPMSM drive provides higher fault-tolerant capability for highreliability applications,e.g.,pumps and actuators in aircraft.For high-power drives with limited switching frequencies and highspeed drives with large fundamental frequencies,the ratio of switching frequency to fundamental frequency,i.e.,the carrier ratio,is usually below 15,which would significantly degrade the control performance.The purpose of this paper is to review the recent work on the modulation and control schemes for improving the operation performance of DTP-PMSM drives with low carrier ratios.Specifically,three categories of methods,i.e.,the space vector modulation based control,the model predictive control(MPC),and the optimized pulse pattern(OPP)based control are reviewed with principles and performance.In addition,brief discussions regarding the comparison and future trends are presented for low-carrier-ratio(LCR)modulation and control schemes of DTP-PMSM drives. 展开更多
关键词 Dual three-phase permanent magnet synchronous motor(DTP-PMSM) Low-carrier-ratio(LCR) Complex vector control Model predictive control(MPC) Optimized pulse pattern(OPP)
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Neural connectivity biotypes:predictors of clinical outcomes and improvement patterns of iTBS treatment in adolescents and young adults with depression
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作者 Weicheng Li Yanan Yin +18 位作者 Zerui You Min Zhang Chengyu Wang Xiaofeng Lan Siming Mai Fan Zhang Zhibo Hu Guanxi Liu Xiaoyu Chen Haiyan Liu Zhanjie Luo Yexian Zeng Yiying Chen Yifang Chen Robin Shao Hanna Lu Roger S McIntyre Yanling Zhou Yuping Ning 《General Psychiatry》 2025年第2期134-143,共10页
Background The heterogeneity of depression limits the treatment outcomes of intermittent theta burst stimulation(iTBS)and hinders the identification of predictive factors.This study investigated functional network con... Background The heterogeneity of depression limits the treatment outcomes of intermittent theta burst stimulation(iTBS)and hinders the identification of predictive factors.This study investigated functional network connectivity and predictors of iTBS treatment outcomes in adolescents and young adults with depression.Aim This study aimed to identify default mode network(DMN)-based connectivity patterns associated with varying iTBS treatment outcomes in depression.Methods Data from a randomised controlled trial of iTBS in depression(n=82)were analysed using a data-driven approach to classify homogeneous subgroups based on the DMN.Connectivity subgroups were compared on depressive symptoms and cognitive function at pretreatment and post-treatment.Furthermore,the predictive significance of baseline inflammatory cytokines on post-treatment outcomes was evaluated.Results Two distinct subgroups were identified.Subgroup 1 exhibited high heterogeneity and greater centrality in the posterior cingulate cortex and retrosplenial cortex,while subgroup 2 showed more homogeneous connectivity patterns and greater centrality in the temporoparietal junction and posterior inferior parietal lobule.No main effect for subgroup,treatment or subgroup×treatment interaction was revealed in the improvement of depressive symptoms.A significant subgroup×treatment interaction related to symbol coding improvement was detected(F=5.22,p=0.026).Within subgroup 1,the active group showed significantly greater improvement in symbol coding compared with the sham group(t=2.30,p=0.028),while baseline levels of interleukin-6 and C-reactive protein emerged as significant indicators for predicting improvements in symbolic coding(R2=0.35,RMSE(root-mean-square error)=5.72,p=0.013).Subgroup 2 showed no significant findings in terms of cognitive improvement or inflammatory cytokines predictions. 展开更多
关键词 default mode DEPRESSION functional network connectivity connectivity patterns identification predictive factorsthis randomised controlled trial default mode network intermittent theta burst stimulation itbs
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CPG-based gait planning and model-independent adaptive time-delay control for lower limb rehabilitation exoskeleton robots
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作者 Zhe Sun Weixin Chen +3 位作者 Bo Chen Hai Wang Jinchuan Zheng Zhihong Man 《Control Theory and Technology》 2025年第4期650-662,共13页
Focusing on the rehabilitation training of hemiplegia patients,this paper proposes a gait-planning strategy based on a central pattern generator and an adaptive time-delay control scheme that utilizes recursive termin... Focusing on the rehabilitation training of hemiplegia patients,this paper proposes a gait-planning strategy based on a central pattern generator and an adaptive time-delay control scheme that utilizes recursive terminal sliding mode for lower limb rehabilitation exoskeleton robots.The central pattern generator network plans a reference gait trajectory for the affected leg,synchronized with the movement of the healthy leg.The proposed adaptive time-delay control scheme possesses a model-independent property due to the mechanism of time-delay estimation,with adaptive control gains that enhance the resilience against system perturbations and a recursive terminal sliding mode control component to achieve a fast convergence rate.According to the Lyapunov stability criterion,it is proved that the gait trajectory-tracking error is uniformly ultimately bounded.Experiments are conducted on a lower limb exoskeleton experimental platform,and the experimental results demonstrate the effectiveness and superiority of the proposed strategies. 展开更多
关键词 Lower limb rehabilitation exoskeleton robot(LLRER) Central pattern generator(CPG) Time-delay estimation(TDE) Sliding mode control(SMC)
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华北平原深层承压水演变规律与保护修复
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作者 赵勇 吴初 +2 位作者 刘蓉 马蒙 陆垂裕 《中国水利》 2026年第2期19-28,共10页
经过持续10年综合治理,华北平原浅层和深层地下水水位整体呈现显著回升的趋势,但深层承压水超采依然存在,诱发地面沉降、海(咸)水入侵等地质环境问题,已经成为当前地下水超采治理修复的焦点和难点。基于系统调查监测、室内外试验、模拟... 经过持续10年综合治理,华北平原浅层和深层地下水水位整体呈现显著回升的趋势,但深层承压水超采依然存在,诱发地面沉降、海(咸)水入侵等地质环境问题,已经成为当前地下水超采治理修复的焦点和难点。基于系统调查监测、室内外试验、模拟分析、治理措施研究与实践总结,本文阐释了华北平原深层承压水埋深变化规律,揭示了承压水超采导致的地面沉降和咸水层变化,识别了深层承压水侧向补给通量,提出华北平原深层承压水可采量、可恢复超采量和地下水水位健康阈值,初步验证井灌回补对咸淡水界面抬升的有效性,并从高效性、持久性和经济性角度提出自然回补的水文地质优势通道,以及浅层微咸水置换利用、加大外调水置换等需要加强的措施,以期为华北平原深层承压水管理与保护修复提供参考。 展开更多
关键词 华北平原 地下水 深层承压水 演变规律 水位阈值 超采治理 井灌回补
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基于Design Patterns的大型工控软件研究与实践 被引量:9
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作者 刘铭 施仁 贾宏宇 《小型微型计算机系统》 CSCD 北大核心 2004年第6期1032-1035,共4页
针对大型工控软件开发面临的各种难题 ,提出了基于设计模式 (Design Patterns)的工控软件设计的解决方案 .在大型电力系统监控软件设计中 ,采用设计模式进行工控软件框架和工位的设计 ,实现了功能模块的松耦合关系 ,降低了代码的复杂度 ... 针对大型工控软件开发面临的各种难题 ,提出了基于设计模式 (Design Patterns)的工控软件设计的解决方案 .在大型电力系统监控软件设计中 ,采用设计模式进行工控软件框架和工位的设计 ,实现了功能模块的松耦合关系 ,降低了代码的复杂度 ,从而提高了运行效率 ,同时也加快了系统开发、调试的效率 .论证了设计模式在工控软件设计中应用的潜力 ,提出了大型工控软件设计的新思路 . 展开更多
关键词 设计模式 面向对象 工控软件
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