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Numerical analysis for the free-boundary current reversal equilibrium in the AC plasma current operation in a tokamak
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作者 胡业民 王柳青 +2 位作者 白书航 于治 夏天阳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期22-30,共9页
In recent decades, tokamak discharges with zero total toroidal current have been reported in tokamak experiments, and this is one of the key problems in alternating current(AC) operations.An efficient free-boundary eq... In recent decades, tokamak discharges with zero total toroidal current have been reported in tokamak experiments, and this is one of the key problems in alternating current(AC) operations.An efficient free-boundary equilibrium code is developed to investigate such advanced tokamak discharges with current reversal equilibrium configuration. The calculation results show that the reversal current equilibrium can maintain finite pressure and also has considerable effects on the position of the X-point and the magnetic separatrix shape, and hence also on the position of the strike point on the divertor plates, which is extremely useful for magnetic design, MHD stability analysis, and experimental data analysis etc. for the AC plasma current operation on tokamaks. 展开更多
关键词 current reversal equilibrium AC operation free-boundary equilibrium TOKAMAK
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Operational optimization of copper flotation process based on the weighted Gaussian process regression and index-oriented adaptive differential evolution algorithm
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作者 Zhiqiang Wang Dakuo He Haotian Nie 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期167-179,共13页
Concentrate copper grade(CCG)is one of the important production indicators of copper flotation processes,and keeping the CCG at the set value is of great significance to the economic benefit of copper flotation indust... Concentrate copper grade(CCG)is one of the important production indicators of copper flotation processes,and keeping the CCG at the set value is of great significance to the economic benefit of copper flotation industrial processes.This paper addresses the fluctuation problem of CCG through an operational optimization method.Firstly,a density-based affinity propagationalgorithm is proposed so that more ideal working condition categories can be obtained for the complex raw ore properties.Next,a Bayesian network(BN)is applied to explore the relationship between the operational variables and the CCG.Based on the analysis results of BN,a weighted Gaussian process regression model is constructed to predict the CCG that a higher prediction accuracy can be obtained.To ensure the predicted CCG is close to the set value with a smaller magnitude of the operation adjustments and a smaller uncertainty of the prediction results,an index-oriented adaptive differential evolution(IOADE)algorithm is proposed,and the convergence performance of IOADE is superior to the traditional differential evolution and adaptive differential evolution methods.Finally,the effectiveness and feasibility of the proposed methods are verified by the experiments on a copper flotation industrial process. 展开更多
关键词 Weighted Gaussian process regression Index-oriented adaptive differential evolution operational optimization Copper flotation process
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Multi-Time Scale Operation and Simulation Strategy of the Park Based on Model Predictive Control
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作者 Jun Zhao Chaoying Yang +1 位作者 Ran Li Jinge Song 《Energy Engineering》 EI 2024年第3期747-767,共21页
Due to the impact of source-load prediction power errors and uncertainties,the actual operation of the park will have a wide range of fluctuations compared with the expected state,resulting in its inability to achieve... Due to the impact of source-load prediction power errors and uncertainties,the actual operation of the park will have a wide range of fluctuations compared with the expected state,resulting in its inability to achieve the expected economy.This paper constructs an operating simulation model of the park power grid operation considering demand response and proposes a multi-time scale operating simulation method that combines day-ahead optimization and model predictive control(MPC).In the day-ahead stage,an operating simulation plan that comprehensively considers the user’s side comfort and operating costs is proposed with a long-term time scale of 15 min.In order to cope with power fluctuations of photovoltaic,wind turbine and conventional load,MPC is used to track and roll correct the day-ahead operating simulation plan in the intra-day stage to meet the actual operating operation status of the park.Finally,the validity and economy of the operating simulation strategy are verified through the analysis of arithmetic examples. 展开更多
关键词 Demand response model predictive control multiple time scales operating simulation
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A 63-Year-Old Male with D-Transposition of the Great Arteries Who Had an Early Form of the Arterial Switch Operation
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作者 Michael A.Rebolledo Jane S.Yao +2 位作者 Jason N.Johnson Umar S.Boston Benjamin R.Waller III 《Congenital Heart Disease》 SCIE 2024年第1期65-68,共4页
We describe a 63-year-old male who appears to have undergone an early form of the arterial switch operation for D-transposition of the great arteries performed in the mid-1960s.We review the clinical and imaging data ... We describe a 63-year-old male who appears to have undergone an early form of the arterial switch operation for D-transposition of the great arteries performed in the mid-1960s.We review the clinical and imaging data that support our conclusion.He had a diagnostic cardiac catheterization which demonstrated severe pulmonary hypertension responsive to epoprostenol and oxygen.Our case may represent one example of the experimental surgical work done prior to Dr.Adibe Jatene’s description of thefirst successful arterial switch performed in 1975. 展开更多
关键词 Adult congenital heart disease arterial switch operation great vessel anomaly imaging(all modalities)
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Operational requirements analysis method based on question answering of WEKG
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作者 ZHANG Zhiwei DOU Yajie +3 位作者 XU Xiangqian MA Yufeng JIANG Jiang TAN Yuejin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期386-395,共10页
The weapon and equipment operational requirement analysis(WEORA) is a necessary condition to win a future war,among which the acquisition of knowledge about weapons and equipment is a great challenge. The main challen... The weapon and equipment operational requirement analysis(WEORA) is a necessary condition to win a future war,among which the acquisition of knowledge about weapons and equipment is a great challenge. The main challenge is that the existing weapons and equipment data fails to carry out structured knowledge representation, and knowledge navigation based on natural language cannot efficiently support the WEORA. To solve above problem, this research proposes a method based on question answering(QA) of weapons and equipment knowledge graph(WEKG) to construct and navigate the knowledge related to weapons and equipment in the WEORA. This method firstly constructs the WEKG, and builds a neutral network-based QA system over the WEKG by means of semantic parsing for knowledge navigation. Finally, the method is evaluated and a chatbot on the QA system is developed for the WEORA. Our proposed method has good performance in the accuracy and efficiency of searching target knowledge, and can well assist the WEORA. 展开更多
关键词 operational requirement analysis weapons and equipment knowledge graph(WEKG) question answering(QA) neutral network
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Evaluation of Driver-Induced Human Errors in Smart Construction Tower Crane Operations Based on DEMATEL-ISM-MICMAC
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作者 Jiahao Wang Wen Si 《Journal of Applied Mathematics and Physics》 2024年第4期1541-1556,共16页
With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing facto... With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing factors, human unsafe behavior stands out as a primary cause for these incidents. This study aims to assess the human reliability of tower crane operations on smart construction sites. To proactively enhance safety measures, the research employs text mining techniques (TF-IDF-Truncated SVD-Complement NB) to identify patterns of human errors among tower crane operators. Building upon the SHEL model, the study categorizes behavioral factors affecting human reliability in the man-machine interface, leading to the establishment of the Performance Shaping Factors (PSFs) system. Furthermore, the research constructs an error impact indicator system for the intelligent construction site tower crane operator interface. Using the DEMATEL method, it analyzes the significance of various factors influencing human errors in tower crane operations. Additionally, the ISM-MICMAC method is applied to unveil the hierarchical relationships and driving-dependent connections among these influencing factors. The findings indicate that personal state, operating procedures, and physical environment directly impact human errors, while personal capability, technological environment, and one fundamental organizational management factor contribute indirectly. . 展开更多
关键词 Text Mining DEMATEL-ISM-MICMAC Performance Shaping Factors Smart Construction Tower Crane Operator
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Research on a Comprehensive Monitoring System for Tunnel Operation based on the Internet of Things and Artificial Intelligence Identification Technology
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作者 Xingxing Wang Donglin Dai Xiangjun Fan 《Journal of Architectural Research and Development》 2024年第2期84-89,共6页
This article proposes a comprehensive monitoring system for tunnel operation to address the risks associated with tunnel operations.These risks include safety control risks,increased traffic flow,extreme weather event... This article proposes a comprehensive monitoring system for tunnel operation to address the risks associated with tunnel operations.These risks include safety control risks,increased traffic flow,extreme weather events,and movement of tectonic plates.The proposed system is based on the Internet of Things and artificial intelligence identification technology.The monitoring system will cover various aspects of tunnel operations,such as the slope of the entrance,the structural safety of the cave body,toxic and harmful gases that may appear during operation,excessively high and low-temperature humidity,poor illumination,water leakage or road water accumulation caused by extreme weather,combustion and smoke caused by fires,and more.The system will enable comprehensive monitoring and early warning of fire protection systems,accident vehicles,and overheating vehicles.This will effectively improve safety during tunnel operation. 展开更多
关键词 Internet of Things Artificial intelligence operation tunnel MONITORING
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Application of Nursing Cooperation Path in Operating Room and Analysis of Complication Rate During Laparoscopic Hysterectomy
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作者 Xiaohong Shen 《Journal of Clinical and Nursing Research》 2024年第1期222-227,共6页
Objective:To explore the clinical benefits achieved by implementing the operating room nursing cooperation path for patients undergoing laparoscopic hysterectomy.Methods:64 laparoscopic hysterectomy cases were divided... Objective:To explore the clinical benefits achieved by implementing the operating room nursing cooperation path for patients undergoing laparoscopic hysterectomy.Methods:64 laparoscopic hysterectomy cases were divided into groups according to the order of admission.The control group received routine perioperative care.The observation group implemented the nursing cooperation path in the operating room on the same basis as the control group.The two groups’physiological responses,stimulus indicators,anxiety,and complication rates were compared.Results:The heart rate,blood pressure 0.5 hours after surgery,anxiety scores 1 day before and 3 days after surgery,and the total number of complications in the observation group were all lower than those in the control group(P<0.05).Conclusion:The development of a nursing cooperation path in the operating room can help patients undergoing laparoscopic hysterectomy reduce heart rate,blood pressure,stress responses,and the risk of complications,and is worthy of promotion. 展开更多
关键词 Laparoscopic hysterectomy Operating room nursing cooperation path COMPLICATIONS
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CLINICAL OBSERVATION ON ACUPOINT DIGITAL PRESSING FOR TREATING IRRITABLE SYMPTOMS AND SIGNS OF POSTOPERATION OF MYOPORTHOSIS
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作者 王晓阳 《World Journal of Acupuncture-Moxibustion》 2002年第3期48-50,共3页
Objective: To explore a new effective approach for treatment of the local irritable symptoms and signs resulted from myoporthosis operation. Methods: 263 cases of radial keratotomy outpatients were divided into contro... Objective: To explore a new effective approach for treatment of the local irritable symptoms and signs resulted from myoporthosis operation. Methods: 263 cases of radial keratotomy outpatients were divided into control group (n=49, 90 eyes) and treatment group (n=214, 412 eyes). Patients of control group were treated with 0.5% Chloramphenicol eye drops, 3 times daily, 1-2 drops/time, and with 0.5% Erythromycine eye ointment every night. In treatment group, patients were treated with acupoint and hand reflection area digital pressing method except with the same eye drops and eye ointment. Body acupoints used were Cuanzhu (BL 2), Yuyao (EX HN 4), Sizhukong (TE 23), Sibai (ST 2) and Taiyang (EX HN 5). The hand reflex areas used were Eye Area, Liver Area, Kidney Area, Spleen Area, Heart Area and Lung Area. Five days constituted a therapeutic course. Results: Following 3 courses (15 days) of treatment, the markedly effective rate and total effective rate of treatment group and control group were 74.51% and 38.89%, 94.17% and 66.67% respectively. There was a significant difference between two groups in the total effective rate (P<0.05), showing the therapeutic effect of treatment group being better than that of control group. Conclusion: Acupoint digital pressing is rather effective in treatment of myoporthosis post operation irritable symptoms and signs. 展开更多
关键词 头部反应区 点压 手穴 穴位数字按压治疗 穴位 术后并发症 myoporthosis
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Endovascular treatment of delayed arterial hemorrhage after radical operation for hilar cholangiocarcinoma 被引量:1
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作者 Xiang-Dong Wang Nai-Jian Ge +3 位作者 Cheng-Jian He Jun-Jun Zhu Wei Xu Ye-Fa Yang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第4期403-405,共3页
Radical operation for hilar cholangiocarcinoma(HCCA)is the most effective treatment,but high rates of severe postoperative complication and death remain concerns due to the complexity of biliary and vascular anatomy o... Radical operation for hilar cholangiocarcinoma(HCCA)is the most effective treatment,but high rates of severe postoperative complication and death remain concerns due to the complexity of biliary and vascular anatomy of the hepatobiliary region.De-layed arterial hemorrhage(DAH)occurring>24 h postoperatively usually causes life-threatening bleeding,and relaparotomy for DAH would be difficult and hazardous because of postoperative adhe-sions and critical general condition.As endovascular technique is less invasive and has improved over the recent decades,clini-cians have begun to prefer endovascular treatment(EVT)to surgi-cal treatment of DAH after hepatobiliary pancreatic surgery.How-ever,to our knowledge,a relatively large series of patients dealing with the outcomes of EVT of DAH after surgery for HCCA has not been reported.Herein,we analyzed the technical and clinical out-comes of EVT in 17 patients to evaluate the efficacy and safety of EVT. 展开更多
关键词 operation ARTERIAL HEMORRHAGE TREATMENT AFTER
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The first attempt for closure of the patent foramen ovale under guidance of teleoperation ultrasonic robot:a case report 被引量:1
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作者 Yu WEI Hao ZHOU +4 位作者 Mang-Xiang ZHAO Chi WANG Shuang-Yi WANG Zhao-Kun DENG Hang ZHU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2023年第2期159-162,共4页
Patent foramen ovale(PFO)is a remnant of normal fetal anatomy,which occurs in about 20%–25%of cases.Patients with PFO are at increased risk for migraine,acute limb ischemia secondary to emboli and cryptogenic(no othe... Patent foramen ovale(PFO)is a remnant of normal fetal anatomy,which occurs in about 20%–25%of cases.Patients with PFO are at increased risk for migraine,acute limb ischemia secondary to emboli and cryptogenic(no other identifiable cause)stroke.The traditional approach has been to use a fluoroscopically guided blocking device,but this is contraindicated in patients with severe allergies to contrast media or inability to undergo angiography.With the advancements in technology,ultrasonic robotic systems have become available for medical procedures.In the current study,we reported a case of using the ultrasonic robotic teleoperation system to achieve closure of PFO at the Chinese PLA General Hospital,Beijing,China. 展开更多
关键词 operation ANATOMY ACUTE
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Associate factors for endoscopic submucosal dissection operation time and postoperative delayed hemorrhage of early gastric cancer 被引量:4
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作者 Ren-Song Cai Wei-Zhong Yang Guang-Rui Cui 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第1期94-104,共11页
BACKGROUND Endoscopic submucosal dissection(ESD)is a treatment for early gastric cancer with the advantages of small invasion,fewer complications,and a low local recurrence rate.However,there is a high risk of complic... BACKGROUND Endoscopic submucosal dissection(ESD)is a treatment for early gastric cancer with the advantages of small invasion,fewer complications,and a low local recurrence rate.However,there is a high risk of complications such as bleeding and perforation,and the operation time is also longer.ESD operation time is closely related to bleeding and perforation.AIM To investigate the influencing factors associated with ESD operation time and postoperative delayed hemorrhage to provide a reference for early planning,early identification,and prevention of complications.METHODS We conducted a retrospective study based on the clinical data of 520 patients with early gastric cancer in the Second Affiliated Hospital of Hainan Medical University from January 2019 to December 2021.The baseline data,clinical features,and endoscopic and pathological characteristics of patients were collected.The multivariate linear regression model was used to investigate the influencing factors of ESD operation time.Logistic regression analysis was carried out to evaluate the influencing factors of postoperative delayed hemorrhage.RESULTS The multivariate analysis of ESD operation time showed that the maximum lesion diameter could affect 8.815%of ESD operation time when other influencing factors remained unchanged.The operation time increased by 3.766%or 10.247%if the lesion was mixed or concave.The operation time increased by 4.417%if combined with an ulcer or scar.The operation time increased by 3.692%if combined with perforation.If infiltrated into the submucosa,it increased by 2.536%.Multivariate analysis of delayed hemorrhage after ESD showed that the maximum diameter of the lesion,lesion morphology,and ESD operation time were independent influencing factors for delayed hemorrhage after ESD.Patients with lesion≥3.0 cm(OR=3.785,95%CI:1.165-4.277),lesion morphology-concave(OR=10.985,95%CI:2.133-35.381),and ESD operation time≥60 min(OR=2.958,95%CI:1.117-3.526)were prone to delayed hemorrhage after ESD.CONCLUSION If the maximum diameter of the lesion in patients with early gastric cancer is≥3.0 cm,and the shape of the lesion is concave,or accompanied by an ulcer or scar,combined with perforation,and infiltrates into the submucosa,the ESD operation will take a longer time.When the maximum diameter of the lesion is≥3.0 cm,the shape of the lesion is concave in patients and the operation time of ESD takes longer time,the risk of delayed hemorrhage after ESD is higher. 展开更多
关键词 Early gastric cancer Endoscopic submucosal dissection operation time Delayed hemorrhage
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Dynamic Analysis of Pipeline Lifting Operations for Different Current Velocities and Wave Heights 被引量:1
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作者 Dapeng Zhang Bowen Zhao Keqiang Zhu 《Fluid Dynamics & Materials Processing》 EI 2023年第3期603-617,共15页
Pipelines are widely used for transporting oil resources in the context of offshore oil exploitation.The pipeline stress-strength analysis is an important stage in related design and ensuing construction techniques.In... Pipelines are widely used for transporting oil resources in the context of offshore oil exploitation.The pipeline stress-strength analysis is an important stage in related design and ensuing construction techniques.In this study,assuming representative work environment parameters,pipeline lifting operations are investigated numerically.More specifically,a time-domain coupled dynamic analysis method is used to conduct a hydrodynamic analysis under different current velocities and wave heights.The results show that proper operation requires the lifting points are reasonably set in combination with the length of the pipeline and the position of the lifting device on the construction ship.The impact of waves on the pipeline is limited,however lifting operations under strong wind and waves should be avoided as far as possible. 展开更多
关键词 PIPELINE OrcaFlex hydrodynamic analysis lifting operation
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A survey on joint-operation application for unmanned swarm formations under a complex confrontation environment
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作者 ZHANG Jialong HAN Kun +2 位作者 ZHANG Pu HOU Zhongxi YE Lei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1432-1446,共15页
With the rapid development of informatization,autonomy and intelligence,unmanned swarm formation intelligent operations will become the main combat mode of future wars.Typical unmanned swarm formations such as ground-... With the rapid development of informatization,autonomy and intelligence,unmanned swarm formation intelligent operations will become the main combat mode of future wars.Typical unmanned swarm formations such as ground-based directed energy weapon formations,space-based kinetic energy weapon formations,and sea-based carrier-based formations have become the trump card for winning future wars.In a complex confrontation environment,these sophisticated weapon formation systems can precisely strike mobile threat group targets,making them extreme deterrents in joint combat applications.Based on this,first,this paper provides a comprehensive summary of the outstanding advantages,strategic position and combat style of unmanned clusters in joint warfare to highlight their important position in future warfare.Second,a detailed analysis of the technological breakthroughs in four key areas,situational awareness,heterogeneous coordination,mixed combat,and intelligent assessment of typical unmanned aerial vehicle(UAV)swarms in joint warfare,is presented.An in-depth analysis of the UAV swarm communication networking operating mechanism during joint warfare is provided to lay the theoretical foundation for subsequent cooperative tracking and control.Then,an indepth analysis of the shut-in technology requirements of UAV clusters in joint warfare is provided to lay a theoretical foundation for subsequent cooperative tracking control.Finally,the technical requirements of UAV clusters in joint warfare are analysed in depth so the key technologies can form a closed-loop kill chain system and provide theoretical references for the study of intelligent command operations. 展开更多
关键词 unmanned swarm operation style weapon formation system mobile group target joint operation
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Proposing Adjustments to the Dry Season Inter-Reservoir Operation Rules of the Red River System to Improve Water Use Efficiency of the Reservoirs
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作者 Thuy T. B. Nguyen Ninh H. Bui 《Journal of Geoscience and Environment Protection》 2023年第5期316-334,共19页
The Red-Thai Binh River system is an important water resource to the Northern Delta, serving the development of agriculture, people’s livelihood and other economic sectors through its upstream reservoirs and a system... The Red-Thai Binh River system is an important water resource to the Northern Delta, serving the development of agriculture, people’s livelihood and other economic sectors through its upstream reservoirs and a system of water abstraction works along the rivers. However, due to the impact of climate change and pressure from socio-economic development, the operation of the reservoir system according to Decision No. 740/QD-TTg was issued on June 17, 2019 by the Prime Minister of Government promulgating the Red-Thai Binh River system inter-reservoir operation rules (Operation rules 740) has some shortcomings that need adjustments for higher water use efficiency, meeting downstream water demand and power generation benefits. Through the results of water balance calculation and analysis of economic benefits from water use scenarios, this research proposed adjustment to the inter-reservoir operation during dry season in the Red River system. The result showed that an average water level of 1.0 - 1.7 m should be maintained at Hanoi during the increased release period. 展开更多
关键词 Inter-Reservoir operation Adjustment operation Rules RESERVOIRS Red-Thai Binh River Basin
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Ergonomic Reliability Assessment of VDT Systemfor Operation Design Based on Improved BPNN and HCR under Special Circumstances
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作者 Xin Liu Zheng Liu +5 位作者 Zhilin Huang Mingyu Ling Kangchao Lin Pengqing Chen Xiaomin Huang Yujia Zhai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期685-707,共23页
Ergonomic reliability plays a significant role in the safe operation of devices.With the spread of infectious diseases around the world,in work environments with high loads and high infection rates,medical staff work ... Ergonomic reliability plays a significant role in the safe operation of devices.With the spread of infectious diseases around the world,in work environments with high loads and high infection rates,medical staff work in a state of high self-protection.The use of visual display terminal(VDT)for medical equipment has undergone fundamental changes,and the traditional medical equipment human-machine interface design needs to be improved.After the completion of design and development,a VDT design enters the experimental testing stage,which has significant limitations for simulating the work of medical staff in the high-load and high-infection environments.The testing cost is high,and subjects face harsh conditions;thus,an ergonomic reliability model that can predict the use of VDT in such special high-infection and high-load circumstances must be established.An ergonomic reliability model based on an improved backpropagation neural network(BPNN)and human cognition reliability(HCR)is proposed for predicting and evaluating operation flows according tomedical equipment VDTs.Firstly,a small data sample can be used to train BPNN to generate a network that can ensure suitable accuracy.To prevent the model from falling into local optimal solutions,the bat algorithm is introduced to improve the BPNN.Compared to a traditional BPNN,the superiority of the improved BPNN is clearly demonstrated.Secondly,the HCR method is used to analyze and highlight changes in the human factor reliability of VDTs for medical equipment in different time processes and operating processes according to BPNN prediction results,to provide a reference for selecting the optimalmethod.Finally,the validity and availability of the proposedmethod are verified through an eye tracker experiment and statistical analysis results. 展开更多
关键词 Ergonomic reliability BPNN HCR operation design VDT HMI
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Anatomic Correlates of Mitral Systolic Anterior Motion in Transposition of the Great Arteries Following Atrial Switch Operation
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作者 Norman Aiad Mark V.Sherrid +7 位作者 Adam J.Small Youssef Elnabawi Jodi Feinberg Leon Axel Ralph Mosca T.K.Susheel Kumar Michael Argilla Dan G.Halpern 《Congenital Heart Disease》 SCIE 2023年第3期267-277,共11页
Introduction:We sought to investigate whether the development of sub-pulmonic systolic anterior motion(SAM)may be inherent to the anatomy of the the mitral valve(MV)or affected by external factors,such as a dilated ri... Introduction:We sought to investigate whether the development of sub-pulmonic systolic anterior motion(SAM)may be inherent to the anatomy of the the mitral valve(MV)or affected by external factors,such as a dilated right ventricle or chest abnormalities in d-looped transposition of the great arteries post atrial switch operation(d-TGA/AtS).Methods:Analysis was performed of clinical and cardiac imaging studies acquired on 19 adult patients with d-TGA/AtS(age 42±6 years old,56%male)between 2015–2019.Echocardiography data included mitral apparatus anatomy,and CT/MRI data included biventricular dimensions,function,and Haller index(HI)for pectus deformity.Results:Patients with leaflet SAM(n=6)compared to patients without SAM(n=13)had higher MV protrusion height(2.3±0.5 vs.1.5±0.4 cm,p≤0.01)and longer anterior MV leaflet length(3.1±0.4 cm vs.2.6±0.3 cm p≤0.05),when compared to those without.CT/MRI showed higher sub-pulmonic left ventricular ejection fraction(LVEF)in the SAM group(71%±8%vs.54%±7%,respectively).RV size and function,significant chest deformity(HI>3.5),presence of a ventricular lead pacemaker,and septal thickness did not play a role in development of SAM.Conclusions:An elongated mitral apparatus is associated with the development of SAM,and the development of left ventricular outflow tract obstruction(LVOTO),in d-TGA/AtS.LV hyperkinesia is associated with SAM.Systemic RV dimensions,septal thickness,and degree of chest deformity did not differ significantly between subjects with SAM and those without. 展开更多
关键词 d-loop transposition of the great arteries mustard operation senning operation systolic anterior motion of the mitral valve ECHOCARDIOGRAPHY cardiac MRI
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Analyzing environmental flow supply in the semi-arid area through integrating drought analysis and optimal operation of reservoir
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作者 Mahdi SEDIGHKIA Bithin DATTA 《Journal of Arid Land》 SCIE CSCD 2023年第12期1439-1454,共16页
This study proposes a novel form of environmental reservoir operation through integrating environmental flow supply,drought analysis,and evolutionary optimization.This study demonstrates that simultaneous supply of do... This study proposes a novel form of environmental reservoir operation through integrating environmental flow supply,drought analysis,and evolutionary optimization.This study demonstrates that simultaneous supply of downstream environmental flow of reservoir as well as water demand is challenging in the semi-arid area especially in dry years.In this study,water supply and environmental flow supply were 40%and 30%in the droughts,respectively.Moreover,mean errors of supplying water demand as well as environmental flow in dry years were 6 and 9 m3/s,respectively.Hence,these results highlight that ecological stresses of the downstream aquatic habitats as well as water supply loss are considerably escalated in dry years,which implies even using environmental optimal operation is not able to protect downstream aquatic habitats properly in the severe droughts.Moreover,available storage in reservoir will be remarkably reduced(averagely more than 30×106 m3 compared with optimal storage equal to 70×106 m3),which implies strategic storage of reservoir might be threatened.Among used evolutionary algorithms,particle swarm optimization(PSO)was selected as the best algorithm for solving the novel proposed objective function.The significance of this study is to propose a novel objective function to optimize reservoir operation in which environmental flow supply is directly addressed and integrated with drought analysis.This novel form of optimization system can overcome uncertainties of the conventional objective function due to considering environmental flow in the objective function as well as drought analysis in the context of reservoir operation especially applicable in semi-arid areas.The results indicate that using either other water resources for water supply or reducing water demand is the only solution for managing downstream ecological impacts of the river ecosystem.In other words,the results highlighted that replanning of water resources in the study area is necessary.Replacing the conventional optimization system for reservoir operation in the semi-arid area with proposed optimization system is recommendable to minimize the negotiations between stakeholders and environmental managers. 展开更多
关键词 OPTIMIZATION reservoir operation DROUGHTS metaheuristic algorithms environmental flow regime
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An Intelligent Control Method for the Low-Carbon Operation of Energy-Intensive Equipment
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作者 Tianyou Chai Mingyu Li +3 位作者 Zheng Zhou Siyu Cheng Yao Jia Zhiwei Wu 《Engineering》 SCIE EI CAS CSCD 2023年第8期84-95,共12页
Based on an analysis of the operational control behavior of operation experts on energy-intensive equipment,this paper proposes an intelligent control method for low-carbon operation by combining mechanism analysis wi... Based on an analysis of the operational control behavior of operation experts on energy-intensive equipment,this paper proposes an intelligent control method for low-carbon operation by combining mechanism analysis with deep learning,linking control and optimization with prediction,and integrating decision-making with control.This method,which consists of setpoint control,self-optimized tuning,and tracking control,ensures that the energy consumption per tonne is as low as possible,while remaining within the target range.An intelligent control system for low-carbon operation is developed by adopting the end-edge-cloud collaboration technology of the Industrial Internet.The system is successfully applied to a fused magnesium furnace and achieves remarkable results in reducing carbon emissions. 展开更多
关键词 Energy-intensive equipment Low-carbon operation Intelligent control End-edge-cloud collaboration technology
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Operations of Knapsack Sprayer and Its Impacts on Physiological Parameters of Selected Operators
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作者 Bukola Olanrewaju Afolabi Akinfoye Oyime Daniel Adejumo +1 位作者 Ayoade Oladele Atere Titus Adeyinka Ilori 《Engineering(科研)》 CAS 2023年第2期59-67,共9页
The study was aimed at determining the impacts of operating Manually Operated Hand Lever Knapsack Sprayers (MOHLKS) on physiological responses of the operators as dependent on anthropometric variations and sex. Twenty... The study was aimed at determining the impacts of operating Manually Operated Hand Lever Knapsack Sprayers (MOHLKS) on physiological responses of the operators as dependent on anthropometric variations and sex. Twenty eight subjects, (4 female, 24 male) Mean ± SD: Age 22.5 ± 1.92, 24.29 ± 2.2 years;Body Mass Index 24.6 ± 4.8, 21.7 ± 2.4 kg/m<sup>2</sup> were employed in the study. Selected anthropometric parameters of weight and height were used to determine body mass index (BMI), with these are arm-reach forward, elbow to fingertip, hand length and hand width were measured to establish human variations in diversity. Subjects undertook the operation at 5 replicates each, before and after which information about operators’ body pain locations and body physiological changes of heart rates were obtained. Measured parameters were used in the determination of expended energy (EE), physiological cost (PC), oxygen intake (VO<sub>2</sub>) and aerobic power (VO<sub>2</sub>max). Alongside with these were operational parameters of stroke, pace and time taken to get the operation done and environmental factors of temperature and relative humidity. The results revealed on the average that the BMI (24.61 ± 4.78 kg/m<sup>2</sup>) in female operators was higher, this corresponded to PC and VO<sub>2</sub>, while the VO<sub>2</sub>max (34.83 ± 3.30 ml/min/kg) in males is higher. More EE was obtained in female subjects (3.53 ± 3.76 kCal/min) as compared to male subjects (3.42 ± 7.48 kCal/min). The main effects plot of operational factors on EE displayed the stroke made by the subjects during spraying operation as parameter with largest effect on EE. Regression equation for EE and PCI is given as PCI = 1.97 + 25.2 EE, while the P-value at α = 0.05 is 0.000 and R<sup>2</sup> = 98.8%. Post operational body pain showed that 19 out of 28 subjects incurred at least one type of body pain, with shoulder pain as most frequent. The results of the study suggest that early incidence of fatigue may occur in female operators as compared to the males, and in addition, cumulative trauma at shoulder, back, and upper and lower arm may result over time. Hence, it is recommended that the tank volume should be reduced and the straps for the shoulders should be supported with additional cushion. 展开更多
关键词 Cumulativetrauma Knapsack Sprayer operational Effect Physiological Changes STROKE
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