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Effect of three-stage fusion nursing intervention the rehabilitation process and psychological stress in patients after gastric cancer surgery
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作者 Xia Zhao 《World Journal of Gastrointestinal Surgery》 2025年第7期319-327,共9页
BACKGROUND Patients with gastric cancer often experience slow postoperative recovery and psychological stress,necessitating enhanced nursing care to improve their prognosis.AIM To analyze the impact of a timing-theory... BACKGROUND Patients with gastric cancer often experience slow postoperative recovery and psychological stress,necessitating enhanced nursing care to improve their prognosis.AIM To analyze the impact of a timing-theory-guided three-stage integrated nursing intervention(TSIN)on the postoperative recovery of patients undergoing gastric cancer surgery.METHODS Total 84 patients that underwent gastric cancer surgeries between June 2022 and June 2024 were selected and divided into a control group and an observation group based on perioperative nursing methods.The control group(n=42)received routine nursing care,whereas the observation group(n=42)received a timing-theory-guided TSIN.The psychological adjustment capabilities,psychological stress,cancer-related fatigue levels,postoperative recovery,and quality of life of the two groups were compared.RESULTS Compared to the control group,the observation group took lesser time to get out of bed,achieve gastrointestinal motility,have the first mealtime,along with a shorter hospital stay(P<0.05).Before nursing,there were no significant differences between groups’parameters or scores(P>0.05).After nursing,the scores for psychological stress and cancer-related fatigue decreased.In contrast,the scores for psychological adjustment capabilities and quality of life increased,with more significant improvements observed in the observation group,showing significant differences within and between the groups(P<0.05).CONCLUSION Timing theory-guided TSIN can improve the psychological adjustment capabilities of patients undergoing gastric cancer surgery,reduce psychological stress and cancer-related fatigue,accelerate postoperative recovery,and improve the quality of life. 展开更多
关键词 Timing theory three-stage integrated nursing Gastric cancer surgery Psychological adjustment Psychological stress Quality of life
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A Three-section Algorithm of Dynamic Programming Based on Three-stage Decomposition System Model for Grade Transition Trajectory Optimization Problems
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作者 魏宇杰 江永亨 黄德先 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第10期1122-1130,共9页
This paper introduces a practical solving scheme of gradetransition trajectory optimization(GTTO) problems under typical certificate-checking–updating framework. Due to complicated kinetics of polymerization,differen... This paper introduces a practical solving scheme of gradetransition trajectory optimization(GTTO) problems under typical certificate-checking–updating framework. Due to complicated kinetics of polymerization,differential/algebraic equations(DAEs) always cause great computational burden and system non-linearity usually makes GTTO non-convex bearing multiple optima. Therefore, coupled with the three-stage decomposition model, a three-section algorithm of dynamic programming(TSDP) is proposed based on the general iteration mechanism of iterative programming(IDP) and incorporated with adaptivegrid allocation scheme and heuristic modifications. The algorithm iteratively performs dynamic programming with heuristic modifications under constant calculation loads and adaptively allocates the valued computational resources to the regions that can further improve the optimality under the guidance of local error estimates. TSDP is finally compared with IDP and interior point method(IP) to verify its efficiency of computation. 展开更多
关键词 Gradetransition TRAJECTORY optimization Adaptivegrid ALLOCATION HEURISTIC modifications Three-section dynamic programming three-stage DECOMPOSITION model
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A CENTRAL-STAGE BUFFERED THREE-STAGE CLOS SWITCHING FABRIC AND THE SCHEDULING ALGORITHM
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作者 Hu Yuxiang Ma Xiangjie Lan Julong Wang Haoxue 《Journal of Electronics(China)》 2009年第1期113-119,共7页
Current MSM switching fabric has poor performance under unbalanced traffic. This paper presents an alternative, novel Central-stage Buffered Three-stage Clos switching (CB-3Clos) fabric and proves that this fabric can... Current MSM switching fabric has poor performance under unbalanced traffic. This paper presents an alternative, novel Central-stage Buffered Three-stage Clos switching (CB-3Clos) fabric and proves that this fabric can emulate output queuing switch without any speedup. By analyzing the condition to satisfy the central-stage load-balance, this paper also proposes a Central-stage Load-balanced-based Distributed Scheduling algorithm (CLDS) for CB-3Clos. The results show that, compared with Concurrent Round-Robin based Dispatching (CRRD) algorithm based on MSM, CLDS algorithm has high throughput irrespective with the traffic model and better performance in mean packet delay. 展开更多
关键词 three-stage Clos switching fabric Central-stage buffered Distributed scheduling Loadbalance
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GSLDWOA: A Feature Selection Algorithm for Intrusion Detection Systems in IIoT
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作者 Wanwei Huang Huicong Yu +3 位作者 Jiawei Ren Kun Wang Yanbu Guo Lifeng Jin 《Computers, Materials & Continua》 2026年第1期2006-2029,共24页
Existing feature selection methods for intrusion detection systems in the Industrial Internet of Things often suffer from local optimality and high computational complexity.These challenges hinder traditional IDS from... Existing feature selection methods for intrusion detection systems in the Industrial Internet of Things often suffer from local optimality and high computational complexity.These challenges hinder traditional IDS from effectively extracting features while maintaining detection accuracy.This paper proposes an industrial Internet ofThings intrusion detection feature selection algorithm based on an improved whale optimization algorithm(GSLDWOA).The aim is to address the problems that feature selection algorithms under high-dimensional data are prone to,such as local optimality,long detection time,and reduced accuracy.First,the initial population’s diversity is increased using the Gaussian Mutation mechanism.Then,Non-linear Shrinking Factor balances global exploration and local development,avoiding premature convergence.Lastly,Variable-step Levy Flight operator and Dynamic Differential Evolution strategy are introduced to improve the algorithm’s search efficiency and convergence accuracy in highdimensional feature space.Experiments on the NSL-KDD and WUSTL-IIoT-2021 datasets demonstrate that the feature subset selected by GSLDWOA significantly improves detection performance.Compared to the traditional WOA algorithm,the detection rate and F1-score increased by 3.68%and 4.12%.On the WUSTL-IIoT-2021 dataset,accuracy,recall,and F1-score all exceed 99.9%. 展开更多
关键词 Industrial Internet of Things intrusion detection system feature selection whale optimization algorithm Gaussian mutation
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Three-stage algorithms for the large-scale dynamic vehicle routing problem with industry 4.0 approach
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作者 Maryam Abdirad Krishna Krishnan Deepak Gupta 《Journal of Management Analytics》 EI 2022年第3期313-329,共17页
Companies are eager to have a smart supply chain especially when they have adynamic system.Industry 4.0 is a concept which concentrates on mobility andreal-time integration.Thus,it can be considered as a necessary com... Companies are eager to have a smart supply chain especially when they have adynamic system.Industry 4.0 is a concept which concentrates on mobility andreal-time integration.Thus,it can be considered as a necessary component thathas to be implemented for a dynamic vehicle routing problem.The aim of thisresearch is to solve large-scale DVRP(LSDVRP)in which the delivery vehiclesmust serve customer demands from a common depot to minimize transit costswhile not exceeding the capacity constraint of each vehicle.In LSDVRP,it isdifficult to get an exact solution and the computational time complexity growsexponentially.To find near-optimal answers for this problem,a hierarchicalapproach consisting of three stages:“clustering,route-construction,routeimprovement”is proposed.The major contribution of this paper is dealing withLSDVRP to propose the three-stage algorithm with better results.The resultsconfirmed that the proposed methodology is applicable. 展开更多
关键词 dynamic vehicle routing problem clustered vehicle routing problem three-stage algorithm industry 4.0
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Investigation on seismic response of a three-stage soil slope supported by anchor frame structure 被引量:8
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作者 LIN Yu-liang LI Ying-xin +1 位作者 ZHAO Lian-heng YANG T Y 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第4期1290-1305,共16页
Based on a typical prototype of a soil slope in engineering practice, a numerical model of a three-stage soil slope supported by the anchor frame structure was established by means of FLAC3D code. The dynamic response... Based on a typical prototype of a soil slope in engineering practice, a numerical model of a three-stage soil slope supported by the anchor frame structure was established by means of FLAC3D code. The dynamic responses of three-stage soil slope and frame structure were studied by performing a series of bidirectional Wenchuan motions in terms of the failure mode of three-stage structure, the acceleration of soil slope, the displacement of frame structure, and the anchor stress of frame structure. The response accelerations in both horizontal and vertical directions are the most largely amplified at the slope top of each stage subjected to different shaking cases. The platforms among the stages reduce the amplification effect of response acceleration. The residual displacement of frame structure increases significantly as the intensity of shaking case increases. The frame structure at each stage presents a combined displacement mode consisting of a translation and a rotation around the vertex. The anchor stress of frame structure is mainly increased by the first intense pulse of Wenchuan seismic wave, and it is sensitive to the intensity of shaking case. The anchor stress of frame structure at the first stage is the most considerably enlarged by earthquake loading. 展开更多
关键词 three-stage soil slope anchor frame structure ACCELERATION DISPLACEMENT anchor stress
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Estimating regional coal resource efficiency in China using three-stage DEA and bootstrap DEA models 被引量:10
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作者 Cui Yijia Huang Guoliang Yin Ziyong 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第5期861-864,共4页
Based on three-stage data envelopment analysis(DEA) model estimates of resource utilization efficiency of coal,we selected 29 provinces from China's 2012 input-output data and used the bootstrap DEA model to corre... Based on three-stage data envelopment analysis(DEA) model estimates of resource utilization efficiency of coal,we selected 29 provinces from China's 2012 input-output data and used the bootstrap DEA model to correct the bias.The results show that the mean overall technical efficiency,pure technical efficiency,and scale efficiency was 0.833,0.998,and 0.711 in 2012,respectively.Moreover,the comprehensive technical efficiency score indicates that the scale is invalid.Area utilization efficiencies for the eastern,central,and western regions were 0.917,0.731,and 0.629,respectively.The results prove that there are significant differences in the distribution of coal resources utilization efficiency across regions. 展开更多
关键词 Coal resource efficiency three-stage DEA Bootstrap DEA Technical efficiency
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Production Efficiency of Two-Oriented Agriculture Based on Three-Stage DEA Model 被引量:10
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作者 ZHAI Huan-huan HE Zheng-chu ZHANG Rui 《Agricultural Science & Technology》 CAS 2010年第4期159-163,共5页
Two-oriented agriculture was a complex organism coupling production,economics,society and ecology.Its development process was affected by various factors such as producers,nature,society,etc.In order to overcome measu... Two-oriented agriculture was a complex organism coupling production,economics,society and ecology.Its development process was affected by various factors such as producers,nature,society,etc.In order to overcome measurement error of traditional data envelopment analysis caused by ignoring random,three-stage DEA model was studied to remove environmental factors and random effects.On the foundation of this model was two-oriented agriculture comprehensive production efficiency of 14 cities were estimated in Hunan Province in 2008,and brown forth corresponding policy proposals to promote agricultural development. 展开更多
关键词 Two-oriented agriculture three-stage DEA model Technical efficiency Scale efficiency
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An Analysis of Operational Efficiency of Agricultural Insurance Agency:Based on Three-Stage DEA Model 被引量:2
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作者 Xuan CHEN Wenhuan WEI 《Asian Agricultural Research》 2016年第12期12-16,共5页
From the perspective of agricultural insurance agency,this paper focuses on the study of operational efficiency of agricultural insurance agency,and analyzes the operational efficiency of agricultural insurance agency... From the perspective of agricultural insurance agency,this paper focuses on the study of operational efficiency of agricultural insurance agency,and analyzes the operational efficiency of agricultural insurance agency and its influencing factors,in order to improve the operational efficiency of agricultural insurance agency,better supply agricultural insurance and achieve the policy effect of agricultural insurance.The results of this paper are as follows:( i) Either comprehensive operational efficiency or scale efficiency of Chinese-funded agency is higher than that of foreign-funded agency,but its pure technical efficiency is lower than that of foreign-funded agency,indicating that the managerial decision ability of Chinese-funded agency is weaker than that of foreign-funded agency,and needs to be improved;( ii) The operational efficiency of professional agricultural insurance agency is higher than that of comprehensive agricultural insurance agency,and the agricultural insurance agency is greatly affected by environmental factors;( iii) The operating time of agricultural insurance agency is proportional to its operational efficiency;( iv) The quality of employees is positively correlated with the capital and cost input difference,but negatively correlated with the difference in the number of employees. Therefore,it is necessary to pay attention to the improvement of employees' working efficiency while laying emphasis on employees' quality. 展开更多
关键词 three-stage DEA Operational efficiency Influencing factors
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Contribution to the Optimization of the Transient Stability of an Electric Power Transmission Network Using a Universal Power Flow Compensator Controlled by a Three-Stage Inverter 被引量:2
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作者 Koko Koko Joseph Nneme Nneme Léandre Ndjakomo Essiane Salomé 《World Journal of Engineering and Technology》 2020年第4期675-688,共14页
The use of an electrical network as close as possible to its limits can lead to its instability in the event of a high amplitude disturbance. The damping of system oscillations can be achieved by conventional means of... The use of an electrical network as close as possible to its limits can lead to its instability in the event of a high amplitude disturbance. The damping of system oscillations can be achieved by conventional means of voltage and speed regulation but also by FACTS (Flexible AC Transmission Systems) devices, which are increasingly used in power networks. In this work, optimal control coordination between a hybrid power flow controller and a three-level inverter was used to improve the transient stability of a transmission line. The UPFC is a combination of a serial compensator (SSSC) and a parallel compensator (STATCOM) both connected to a DC-LINK DC bus. The SSSC acts as a voltage source for the network and injects a voltage that can be adjusted in phase and amplitude in addition to the network voltage;the STATCOM acts as a current source. The approach used is tested in the Matlab Simulink environment on a single machine network. Optimal controller tuning gives a better transient stability improvement by reducing the transport angle oscillations from 248.17% to 9.85%. 展开更多
关键词 FACTS UPFC three-stage Inverter PI Power Transit Transient Stability
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Improving Bandwidth of Three-Stage Electro-Hydraulic Servo Valve Based on Speed-Feedback 被引量:1
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作者 刘小初 何景峰 +2 位作者 叶正茂 丛大成 韩俊伟 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期494-498,共5页
In order to improve the dynamic response bandwidth of three-stage electro-hydraulic servo valve,a new method,speed-feedback control is presented in this paper.The construction and principle of three-stage electro-hydr... In order to improve the dynamic response bandwidth of three-stage electro-hydraulic servo valve,a new method,speed-feedback control is presented in this paper.The construction and principle of three-stage electro-hydraulic servo valve are explained,and the mathematical model of three-stage electro-hydraulic servo valve is built in frequency domain.Experimental and simulation results show that the bandwidth compared with proportional control is improved under speed-feedback control.Moreover,the research results play an important role in developing high performance three-stage electro-hydraulic servo valve. 展开更多
关键词 three-stage electro-hydraulic serw walve BANDWIDTH speed-feedback construction PRINCIPLE model simulation experimental test
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Numerical Simulation of Enhanced Oil-Water Separation in a Three-Stage Double-Stirring Extraction Tank 被引量:3
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作者 Lü Chao Zhang Zimu +3 位作者 Zhao Qiuyue Wang Shuchan Zhang Ting'an Liu Yan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第4期121-126,共6页
Numerical simulation of enhanced fluid flow characteristics in a three-stage double-stirring extraction tank was conducted with the coupling of an Eulerian multiphase flow model and a Morsi-Alexander interphase drag f... Numerical simulation of enhanced fluid flow characteristics in a three-stage double-stirring extraction tank was conducted with the coupling of an Eulerian multiphase flow model and a Morsi-Alexander interphase drag force model. Results show that the addition of a stirring device into the settler can efficiently reduce the volume fraction of out-of-phase impurity in the outlet, and accelerate the settling separation of oil-water mixture. Such addition can also effectively break down the oil-water-wrapped liquid droplets coming from the mixer, inhibit reflux from the outlet, and improve the oil-water separation. The addition of a stirring device induces ignorable power consumption compared with that by the mixer, and can thus facilitate the commercialized promotion of this novel equipment. 展开更多
关键词 three-stage extraction tank double-stirring numerical simulation flow characteristics power
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A Unique Orogenic System with Three-Stage Rapakivi Granites in the World:Proterozoic,Palaeozoic and Mesozoic Rapakivi Granites in the China Central Orogenic System 被引量:1
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作者 WANG Xiaoxia WANG Tao +2 位作者 LU Xinxiang HU Nenggao XIAO Qinghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第5期1909-1910,共2页
Objective Rapakivi granites,characterized by rapakivi texture,Atype granite feature and an anorogenic setting,commonly occur in the Proterozoic of the Northern Hemisphere(Fig.la).Recently,more and more Phanerozoic r... Objective Rapakivi granites,characterized by rapakivi texture,Atype granite feature and an anorogenic setting,commonly occur in the Proterozoic of the Northern Hemisphere(Fig.la).Recently,more and more Phanerozoic rapakivi granite suites have been identified and some even occur in orogenic belts.Significantly,three-stage,Proterozoic. 展开更多
关键词 NCC A Unique Orogenic System with three-stage Rapakivi Granites in the World
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KAEA: A Novel Three-Stage Ensemble Model for Software Defect Prediction 被引量:2
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作者 Nana Zhang Kun Zhu +1 位作者 Shi Ying Xu Wang 《Computers, Materials & Continua》 SCIE EI 2020年第7期471-499,共29页
Software defect prediction is a research hotspot in the field of software engineering.However,due to the limitations of current machine learning algorithms,we can’t achieve good effect for defect prediction by only u... Software defect prediction is a research hotspot in the field of software engineering.However,due to the limitations of current machine learning algorithms,we can’t achieve good effect for defect prediction by only using machine learning algorithms.In previous studies,some researchers used extreme learning machine(ELM)to conduct defect prediction.However,the initial weights and biases of the ELM are determined randomly,which reduces the prediction performance of ELM.Motivated by the idea of search based software engineering,we propose a novel software defect prediction model named KAEA based on kernel principal component analysis(KPCA),adaptive genetic algorithm,extreme learning machine and Adaboost algorithm,which has three main advantages:(1)KPCA can extract optimal representative features by leveraging a nonlinear mapping function;(2)We leverage adaptive genetic algorithm to optimize the initial weights and biases of ELM,so as to improve the generalization ability and prediction capacity of ELM;(3)We use the Adaboost algorithm to integrate multiple ELM basic predictors optimized by adaptive genetic algorithm into a strong predictor,which can further improve the effect of defect prediction.To effectively evaluate the performance of KAEA,we use eleven datasets from large open source projects,and compare the KAEA with four machine learning basic classifiers,ELM and its three variants.The experimental results show that KAEA is superior to these baseline models in most cases. 展开更多
关键词 Software defect prediction KPCA adaptive genetic algorithm extreme learning machine ADABOOST
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A Comparative Study on the Land Use Efficiency of Three Urban Agglomerations-Based on the Three-Stage DEA Model 被引量:1
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作者 Yang Lu 《Management Studies》 2021年第3期190-202,共13页
This paper uses a three-stage DEA model to measure the land use efficiency of the three major urban agglomerations in the Yangtze River Delta,Beijing-Tianjin-Hebei,and the Pearl River Delta from 2007 to 2018.The follo... This paper uses a three-stage DEA model to measure the land use efficiency of the three major urban agglomerations in the Yangtze River Delta,Beijing-Tianjin-Hebei,and the Pearl River Delta from 2007 to 2018.The following conclusions are drawn through research:first,the urban land use efficiency of the three major urban agglomerations in the Yangtze River Delta,Beijing-Tianjin-Hebei,and the Pearl River Delta all showed a downward trend,with the rates of decline being 6.06%,2.86%,and 24.34%respectively.In particular,the Pearl River Delta urban agglomeration had the largest decline.Second,the overall urban land use efficiency of the Beijing-Tianjin-Hebei urban agglomeration is relatively high,and the amount of redundancy is relatively small.The rate of decline is significantly lower than the urban land use efficiency of the two major urban agglomerations in the Yangtze River Delta and the Pearl River Delta.The land use efficiency of the Yangtze River Delta and Pearl River Delta urban agglomerations is in a state of continuous decline.Third,the proportion of cities with the effectiveness of returns to scale of urban land use efficiency in the three major urban agglomerations has decreased by 10.53%,10%,and 33.34%,respectively.The Pearl River Delta has the largest decline.Fourth,the land use efficiency of the Yangtze River Delta urban agglomeration is quite different.The central-peripheral phenomenon is evident for the Beijing-Tianjin-Hebei urban agglomerations and the Pearl River Delta urban agglomerations. 展开更多
关键词 three-stage DEA model three city groups land use efficiency
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Effects of standardized three-stage rehabilitation combined with edaravone therapy on the neurotrophic state and oxidative stress injury in patients with cerebral infarction 被引量:1
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作者 Xin-Qun Huang Xia Zhou 《Journal of Hainan Medical University》 2017年第24期130-133,共4页
Objective: To investigate the effects of standardized three-stage rehabilitation combined with edaravone therapy on the neurotrophic state and oxidative stress injury in patients with cerebral infarction. Methods: A t... Objective: To investigate the effects of standardized three-stage rehabilitation combined with edaravone therapy on the neurotrophic state and oxidative stress injury in patients with cerebral infarction. Methods: A total of 90 patients with acute cerebral infarction who were treated in the hospital between May 2015 and April 2017 were divided into control group (n=45) and observation group (n=45) by random number table. Control group received edaravone therapy, and observation group received standardized three-stage rehabilitation combined with edaravone therapy. The differences in neurotrophic state and oxidative stress injury were compared between the two groups before and after treatment. Results: There was no statistically significant difference in serum levels of neurotrophic indexes and oxidative stress indexes between the two groups before treatment. After treatment, serum neurotrophic indexes BDNF and NGF levels of observation group were higher than those of control group;serum oxidation indexes AOPPs, LHP and MDA levels were lower than those of control group whereas SOD, CAT and T-AOC levels were higher than those of control group. Conclusion:Standardized three-stage rehabilitation combined with edaravone therapy can effectively optimize the neurotrophic state and inhibit the oxidative stress in patients with cerebral infarction. 展开更多
关键词 CEREBRAL INFARCTION Standardized three-stage REHABILITATION EDARAVONE NEUROTROPHIC state Oxidative stress injury
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Two-Stage Inspection Model Based on a Three-Stage Failure Process
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作者 杨瑞锋 康建设 王广彦 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期215-218,共4页
As the non-periodic inspections are common in practice,a two-stage inspection model based on a three-stage failure process is proposed. The two-stage inspection means that the system is inspected with the first inspec... As the non-periodic inspections are common in practice,a two-stage inspection model based on a three-stage failure process is proposed. The two-stage inspection means that the system is inspected with the first inspection interval T_1 and the second inspection interval T_2. Because of the three color schemes commonly used in industry,three stages are divided by the system lifetime:normal, minor defective and severe defective stages. Upon the failure of the system,replacement is carried out. Maintenance is done once identifying the severe defective stage. However,when the minor defective stage is identified by the second inspection interval T_2,action of halving the subsequent inspection interval is adopted.Otherwise,no action is required. Our objective function is to optimize the inspection intervals so as to minimize the expected cost per unit time. Finally,a numerical example is presented to illustrate the effectiveness of the proposed model. 展开更多
关键词 delay time two-stage inspection three-stage failure process preventive maintenance(PM)
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A Three-Stage Cutting Simulation System Based on Mass-Spring Model
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作者 Xiaorui Zhang Jiali Duan +2 位作者 Wei Sun Tong Xu Sunil Kumar Jha 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第4期117-133,共17页
The cutting simulation of soft tissue is important in virtual surgery.It includes three major challenges in computation:Soft tissue simulation,collision detection,and handling,as well as soft tissue models.In order to... The cutting simulation of soft tissue is important in virtual surgery.It includes three major challenges in computation:Soft tissue simulation,collision detection,and handling,as well as soft tissue models.In order to address the earlier challenges,we propose a virtual cutting system based on the mass-spring model.In this system,MSM is utilized to simulate the soft tissue model.Residual stress is introduced to the model for simulating the shrinking effect of soft tissue in cutting.Second,a cylinder-based collision detection method is used to supervise the collision between surgical tools and soft tissue.Third,we simulate the cutting operation with a three-stage cutting method with swept volume,B´ezier curve,and an algorithm named shortest distance nodes matching method.In order to verify the system performance,we carry out three validation experiments on the proposed system:Cutting accuracy experiment,collision detection validation,and practical cutting evaluation.Experiments indicate that our system can well perform the shrinking effect of soft tissue in cutting.The system has fast and accurate collision detection.Moreover,the system can reconstruct smooth incisions vividly. 展开更多
关键词 Mass-spring model collision algorithm virtual surgery soft tissue simulation
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Calculation of Agricultural Production Efficiency Based on a Three-stage Data Envelopment Analysis Model and Analysis of the Spatial-temporal Characteristics: A Case Study of the Yangtze River Economic Belt
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作者 Wenjun ZHUO Haiyang CUI 《Meteorological and Environmental Research》 CAS 2021年第5期68-76,83,共10页
In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,th... In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,the Yangtze River Economic Belt is adjusting the agricultural industry structure,optimizing the input-output ratio,and ensuring stable and sustainable agricultural production. Based on the combination of the three-stage Data Envelopment Analysis( DEA) model and cluster analysis,this study examined the Yangtze River Economic Belt from 2008 to 2018 to measure its agricultural production efficiency and to analyze its temporal and spatial characteristics. Studies showed that exogenous environmental factors significantly( P < 5%) impacted agricultural production efficiency in the Yangtze River Economic Zone,and there were temporal and spatial differences. These included:(1) after excluding environmental factors,the overall agricultural production efficiency of the Yangtze River Economic Zone had improved. Sichuan Province and Jiangsu Province were at the forefront of efficiency,whereas the agricultural production efficiency of Shanghai had declined obviously.(2) The agricultural production efficiency of the Yangtze River Economic Belt varied year by year,with fluctuating development. The middle reaches of the Yangtze River had advanced agricultural production efficiency more than the upstream and downstream regions,and the agricultural production efficiency of the individual provinces did not match their economic and social development.(3) Increases in labor,land,irrigation,and other input factors increased agriculture production efficiency,and there was no correlation between fiscal investment,per capita gross domestic product( GDP) and agricultural production efficiency,while the disaster-affected area had a significantly negative impact on agricultural production efficiency. 展开更多
关键词 Agricultural production efficiency three-stage Date Envelopment Analysis Temporal and spatial characteristics Yangtze River Economic Belt
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Method for Estimating the State of Health of Lithium-ion Batteries Based on Differential Thermal Voltammetry and Sparrow Search Algorithm-Elman Neural Network 被引量:1
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作者 Yu Zhang Daoyu Zhang TiezhouWu 《Energy Engineering》 EI 2025年第1期203-220,共18页
Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery systems.However,curr... Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery systems.However,current SOH estimation methods often overlook the valuable temperature information that can effectively characterize battery aging during capacity degradation.Additionally,the Elman neural network,which is commonly employed for SOH estimation,exhibits several drawbacks,including slow training speed,a tendency to become trapped in local minima,and the initialization of weights and thresholds using pseudo-random numbers,leading to unstable model performance.To address these issues,this study addresses the challenge of precise and effective SOH detection by proposing a method for estimating the SOH of lithium-ion batteries based on differential thermal voltammetry(DTV)and an SSA-Elman neural network.Firstly,two health features(HFs)considering temperature factors and battery voltage are extracted fromthe differential thermal voltammetry curves and incremental capacity curves.Next,the Sparrow Search Algorithm(SSA)is employed to optimize the initial weights and thresholds of the Elman neural network,forming the SSA-Elman neural network model.To validate the performance,various neural networks,including the proposed SSA-Elman network,are tested using the Oxford battery aging dataset.The experimental results demonstrate that the method developed in this study achieves superior accuracy and robustness,with a mean absolute error(MAE)of less than 0.9%and a rootmean square error(RMSE)below 1.4%. 展开更多
关键词 Lithium-ion battery state of health differential thermal voltammetry Sparrow Search algorithm
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