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Practice of Infection Prevention and Control Strategies in Risk Departments during the COVID-19 Epidemic
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作者 Minfang Wang Wenyi Ye +7 位作者 Jiefeng Huang Yuexian Zhu Xuxia Yu Hao Huang Fang Xu Bo Jin Ying Yang Tieer Gan 《Advances in Infectious Diseases》 CAS 2024年第1期1-12,共12页
Objective: To explore the practice and application of infection prevention and control strategies in risk departments during the COVID-19 epidemic, and to formulate the infection prevention and control measures to pro... Objective: To explore the practice and application of infection prevention and control strategies in risk departments during the COVID-19 epidemic, and to formulate the infection prevention and control measures to provide advice and guidance in risk departments. Methods: According to the latest plan of diagnosis and treatment, prevention and control issued by the National Health Commission, expert advice and consensus, combined with the actual situation in our hospital, a series of infection prevention and control measures of COVID-19 in risk department was formulated. Results: During the epidemic period, the prevention and control measures of nine risk departments including emergency operation, anesthesiology, endoscopy center, blood purification center, otolaryngology, stomatology, medical imaging department, medical cosmetology department and pulmonary function room were established from six aspects, including pre-examination and screening, medical technology control, personnel management, personal protection, environmental disinfection, medical waste disposal, etc. Conclusion: During the epidemic period, the infection prevention and control strategy of risk departments is one of the key links to control the spread of the epidemic, and risk departments must pay attention to and strictly implement various infection prevention and control measures. 展开更多
关键词 COVID-19 Risk Department Infection Prevention and control STRATEGY PRACTICE
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Prevention and Control Strategies of Nosocomial Infection and Effectiveness Evaluation in a Tertiary Teaching Hospital during the Epidemic of COVID-19
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作者 Minfang Wang Wenyi Ye +7 位作者 Zhe Han Lu Yang Dawei Huang Xuxia Yu Yuexian Zhu Shuangying Huang Ying Yang Tieer Gan 《Advances in Infectious Diseases》 CAS 2024年第1期233-247,共15页
Objective: To evaluate the role of prevention and control strategies for nosocomial infection in a tertiary teaching hospital during the sudden outbreak of Corona Virus Disease 2019 (COVID-19). Methods: The hospital i... Objective: To evaluate the role of prevention and control strategies for nosocomial infection in a tertiary teaching hospital during the sudden outbreak of Corona Virus Disease 2019 (COVID-19). Methods: The hospital initiated an emergency plan involving multi-departmental defense and control. It adopted a series of nosocomial infection prevention and control measures, including strengthening pre-examination and triage, optimizing the consultation process, improving the hospital’s architectural composition, implementing graded risk management, enhancing personal protection, and implementing staff training and supervision. Descriptive research was used to evaluate the short-term effects of these in-hospital prevention and control strategies. The analysis compared changes in related evaluation indicators between January 24, 2020 and February 12, 2020 (Chinese Lunar New Year’s Eve 2020 to lunar January 19) and the corresponding lunar period of the previous year. Results: Compared to the same period last year, the outpatient fever rate increased by 1.85-fold (P P Conclusion: The nosocomial infection prevention and control strategies implemented during this specific period improved the detection and control abilities for the COVID-19 source of infection and enhanced the compliance with measures. This likely contributed significantly to avoiding the occurrence of nosocomial infection. 展开更多
关键词 Corona Virus Disease 2019 Nosocomial Infection Prevention and control Strategy Effectiveness Evaluation
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Analysis of International Cooperation Management Strategies of Enterprises under the Background of the“Belt and Road”
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作者 Nan Hua 《Proceedings of Business and Economic Studies》 2024年第4期238-243,共6页
With the deepening of the“Belt and Road”initiative,Chinese enterprises are facing unprecedented opportunities and challenges for international cooperation.This paper mainly analyzes the current situation,existing pr... With the deepening of the“Belt and Road”initiative,Chinese enterprises are facing unprecedented opportunities and challenges for international cooperation.This paper mainly analyzes the current situation,existing problems,and coping strategies of enterprise international cooperation management in the context of the“Belt and Road”.This article expounds on the importance of the“Belt and Road”initiative for international cooperation of enterprises and analyzes the key links of international cooperation management of enterprises from the aspects of internationalization strategy,cross-cultural management,risk prevention and control,and resource integration.Finally,combined with the case,this paper puts forward the management strategies and suggestions that enterprises should adopt in international cooperation,to provide a useful reference for Chinese enterprises in international cooperation in the construction of the“Belt and Road.” 展开更多
关键词 Belt and Road International cooperation among enterprises Management strategy Cross-cultural management Risk prevention and control
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Empowering women to combat osteoporosis:unveiling the causes,consequences,and control strategies
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作者 Seyi Samson Enitan Babatunde Ishola Gabriel Adejumo +4 位作者 Esther Ngozi Adejumo Temitope Oyewole Olusanya Eguagie Osareniro Osakue Oluwakemi Anike Ladipo Comfort Bosede Enitan 《Aging Communications》 2023年第3期8-17,共10页
Osteoporosis is a common bone disease in women worldwide, leading to decreased bone density and an accelerated risk of fractures. The causes of osteoporosis in women include age (senile osteoporosis), menopause-associ... Osteoporosis is a common bone disease in women worldwide, leading to decreased bone density and an accelerated risk of fractures. The causes of osteoporosis in women include age (senile osteoporosis), menopause-associated hormonal changes, deficiencies in calcium and vitamin D, genetics, lifestyle factors, medical conditions, and some type of medications. The consequences of osteoporosis are colossal, consisting of fractures, decreased quality of life, psychological impacts, and economic burden. To effectively control the menace of osteoporosis in women, numerous strategies are advocated. Adequate calcium and vitamin D consumption through diet or supplements is vital. Regular weight-bearing activities and strength training that promote bone density. Maintaining a healthy life-style through avoiding smoking, limiting alcohol in-take and maintaining a wholesome body weight is essential. Hormone replacement therapy and some medications may be recommended in certain cases. Early detection through regular bone density and blood tests is crucial to lowering its impact. Creating a supportive network through educational programs and resources fosters awareness and empowerment. By engaging these strategies, women can be empowered to combat osteoporosis, reduce fracture risk, and build stronger bones for their overall well-being. 展开更多
关键词 WOMEN AGING OSTEOPOROSIS CAUSES consequences control strategies
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Occurrence Dynamics and Control Strategies of Major Pests and Diseases of Sugarcane in Yunnan
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作者 李文凤 张荣跃 +4 位作者 单红丽 尹炯 王晓燕 罗志明 黄应昆 《Agricultural Science & Technology》 CAS 2017年第12期2490-2494,共5页
In recent years, the occurrence and harm of many kinds of pests and diseases have become increasingly serious in Yunnan sugarcane areas, which have greatly affected the sustained and stable development of sugarcane pr... In recent years, the occurrence and harm of many kinds of pests and diseases have become increasingly serious in Yunnan sugarcane areas, which have greatly affected the sustained and stable development of sugarcane production, so the situation of their prevention and control has become rigorous. In order to scien- tifically and effectively prevent and control pests and diseases of sugarcane to en- sure the safety of sugarcane production, on the basis of an investigation and re- search, according to the present situation of sugarcane production in Yunnan, the occurrence dynamics of major pests and diseases of sugarcane were analyzed, and corresponding control strategies were proposed according to the major pests and diseases as well as their occurrence and damage characteristics. 展开更多
关键词 Yunnan sugarcane areas SUGARCANE Pests and diseases Occurrencedynamics control strategies
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Control strategies and experimental verifications of the electromagnetic mass damper system for structural vibration control 被引量:5
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作者 张春巍 欧进萍 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第2期181-192,共12页
The electromagnetic mass damper (EMD) control system, as an innovative active control system to reduce structural vibration, offers many advantages over traditional active mass driver/damper (AMD) control systems.... The electromagnetic mass damper (EMD) control system, as an innovative active control system to reduce structural vibration, offers many advantages over traditional active mass driver/damper (AMD) control systems. In this paper, studies of several EMD control strategies and bench-scale shaking table tests of a two-story model structure are described. First, two structural models corresponding to uncontrolled and Zeroed cases are developed, and parameters of these models are validated through sinusoidal sweep tests to provide a basis for establishing an accurate mathematical model for further studies. Then, a simplified control strategy for the EMD system based on the pole assignment control algorithm is proposed. Moreover, ideal pole locations are derived and validated through a series of shaking table tests. Finally, three benchmark earthquake ground motions and sinusoidal sweep waves are imposed onto the structure to investigate the effectiveness and feasibility of using this type of innovative active control system for structural vibration control. In addition, the robustness of the EMD system is examined. The test results show that the EMD system is an effective and robust system for the control of structural vibrations. 展开更多
关键词 structural vibration control electromagnetic mass damper (EMD) system control strategy shaking table test pole assignment control robustness
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Nosocomial infections and their control strategies 被引量:4
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作者 Hassan Ahmed Khan Aftab Ahmad Riffat Mehboob 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第7期505-509,共5页
Nosocomial infections are also known as hospital-acquired/associated infections. National Healthcare Safety Network along with Centers for Disease Control for surveillance has classified nosocomial infection sites int... Nosocomial infections are also known as hospital-acquired/associated infections. National Healthcare Safety Network along with Centers for Disease Control for surveillance has classified nosocomial infection sites into 13 types with 50 infection sites, which are specific on the basis of biological and clinical criteria. The agents that are usually involved in hospitalacquired infections include Streptococcus spp., Acinetobacter spp., enterococci, Pseudomonas aeruginosa, coagulase-negative staphylococci, Staphylococcus aureus, Bacillus cereus, Legionella and Enterobacteriaceae family members, namely, Proteus mirablis, Klebsiella pneumonia, Escherichia coli, Serratia marcescens. Nosocomial pathogens can be transmitted through person to person, environment or contaminated water and food, infected individuals, contaminated healthcare personnel's skin or contact via shared items and surfaces. Mainly, multi-drug-resistant nosocomial organisms include methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Pseudomonas aeruginosa and Klebsiella pneumonia, whereas Clostridium difficile shows natural resistance. Excessive and improper use of broadspectrum antibiotics, especially in healthcare settings, is elevating nosocomial infections, which not only becomes a big health care problem but also causes great economic and production loss in the community. Nosocomial infections can be controlled by measuring and comparing the infection rates within healthcare settings and sticking to the best healthcare practices. Centers for Disease Control and Prevention provides the methodology for surveillance of nosocomial infections along with investigation of major outbreaks. By means of this surveillance, hospitals can devise a strategy comprising of infection control practices. 展开更多
关键词 HOSPITAL-ACQUIRED INFECTION ANTIBIOTICS control strategies SURVEILLANCE
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Heat flow balance and control strategies for a large GSHP
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作者 陈义波 陈九法 +2 位作者 Umberto Berardi 乔未来 陈军伟 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期92-98,共7页
The possibility of underground imbalance between heat emission and absorption has a negative impact on the performance of ground-source heat pump systems (GSHPs). Numerical and experimental researches were made in a... The possibility of underground imbalance between heat emission and absorption has a negative impact on the performance of ground-source heat pump systems (GSHPs). Numerical and experimental researches were made in a residential building, which is supplied with a GSHP system and a ceiling radiation system combined with a replacement fresh air system. EnergyPlus simulations were used to estimate heating and cooling loads, and to assess the heat generated from the water pump, the fan and the heat pump unit. Then, Fluent simulations were used to compare three different control strategies of handling the underground heat exchange. These simulations were strongly based on an experimentally verified model. It is obtained that a ratio between cooling and heating loads is 5.08 : 1 in a case study in Nanjing. Moreover, the control strategy based on the starting time is more efficient and reliable than the temperature and temperature difference strategies to control the underground heat exchange. 展开更多
关键词 ground-source heat pump system residential building heat balance control strategy
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Fuzzy Controller Based 3Phase 4Wire Shunt Active Filter for Mitigation of Current Harmonics with Combined p-q and Id-Iq Control Strategies 被引量:4
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作者 Mikkili Suresh Anup Kumar Panda Y. Suresh 《Energy and Power Engineering》 2011年第1期43-52,共10页
As more and more variable frequency drives (VFDs), electronic ballasts, battery chargers, and static Var compensators are installed in facilities, the problems related to harmonics are expected to get worse. As a resu... As more and more variable frequency drives (VFDs), electronic ballasts, battery chargers, and static Var compensators are installed in facilities, the problems related to harmonics are expected to get worse. As a result Active power filter (APF) gains much more attention due to excellent harmonic compensation. But still the performance of the active filter seems to be in contradictions with different control strategies. This paper presents detailed analysis to compare and elevate the performance of two control strategies for ex-tracting reference currents of shunt active filters under balanced, un-balanced and non-sinusoidal conditions by using Fuzzy controller. The well known methods, instantaneous real active and reactive power method (p-q) and active and reactive current method (id-iq) are two control methods which are extensively used in active filters. Extensive Simulations are carried out with fuzzy controller for both p-q and Id-Iq methods for different voltage conditions and adequate results were presented. Simulation results validate the superior per-formance of active and reactive current control strategy (id-iq) with fuzzy controller over active and reactive power control strategy (p-q) with fuzzy controller. 展开更多
关键词 HARMONIC Compensation SHUNT Active Power Filter p-q control STRATEGY id-iq control STRATEGY Fuzzy controller
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Application and Analysis of Force Control Strategies to Deburring and Grinding 被引量:14
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作者 Frank Domroes Carsten Krewet Bernd Kuhlenkoetter 《Modern Mechanical Engineering》 2013年第2期11-18,共8页
This paper aims to give an insight into the development and evaluation of force controlled machining processes with a commercially available setup. We will focus on a deburring and a grinding scenario, representing th... This paper aims to give an insight into the development and evaluation of force controlled machining processes with a commercially available setup. We will focus on a deburring and a grinding scenario, representing the major applications in today’s robot machining. Whereas the deburring use-case implements a force dependent feed-rate control, the grinding use-case implements an orthogonal force (pressure) control. Both strategies will be evaluated and the influence of general machining and robot specific parameters will be discussed. 展开更多
关键词 ROBOT MACHINING DEBURRING GRINDING FORCE control strategies
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Path Planning and Tracking Control for Parking via Soft Actor-Critic Under Non-Ideal Scenarios 被引量:1
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作者 Xiaolin Tang Yuyou Yang +3 位作者 Teng Liu Xianke Lin Kai Yang Shen Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期181-195,共15页
Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adja... Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adjacent parking lots, which poses a safety threat to vehicles parked in these parking lots. However, previous studies have not addressed this issue. In this paper, we aim to evaluate the impact of parking deviation of existing vehicles next to the target parking lot(PDEVNTPL) on the automatic ego vehicle(AEV) parking, in terms of safety, comfort, accuracy, and efficiency of parking. A segmented parking training framework(SPTF) based on soft actor-critic(SAC) is proposed to improve parking performance. In the proposed method, the SAC algorithm incorporates strategy entropy into the objective function, to enable the AEV to learn parking strategies based on a more comprehensive understanding of the environment. Additionally, the SPTF simplifies complex parking tasks to maintain the high performance of deep reinforcement learning(DRL). The experimental results reveal that the PDEVNTPL has a detrimental influence on the AEV parking in terms of safety, accuracy, and comfort, leading to reductions of more than 27%, 54%, and 26%respectively. However, the SAC-based SPTF effectively mitigates this impact, resulting in a considerable increase in the parking success rate from 71% to 93%. Furthermore, the heading angle deviation is significantly reduced from 2.25 degrees to 0.43degrees. 展开更多
关键词 Automatic parking control strategy parking deviation(APS) soft actor-critic(SAC)
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Role of laser scan strategies in defect control,microstructural evolution and mechanical properties of steel matrix composites prepared by laser additive manufacturing 被引量:4
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作者 Hong-yu Chen Dong-dong Gu +5 位作者 Qing Ge Xin-yu Shi Hong-mei Zhang Rui Wang Han Zhang Konrad Kosiba 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第3期462-474,共13页
Steel matrix composites(SMCs)reinforced with WC particles were fabricated via selective laser melting(SLM)by employing various laser scan strategies.A detailed relationship between the SLM strategies,defect formation,... Steel matrix composites(SMCs)reinforced with WC particles were fabricated via selective laser melting(SLM)by employing various laser scan strategies.A detailed relationship between the SLM strategies,defect formation,microstructural evolution,and mechanical properties of SMCs was established.The laser scan strategies can be manipulated to deliberately alter the thermal history of SMC during SLM processing.Particularly,the involved thermal cycling,which encompassed multiple layers,strongly affected the processing quality of SMCs.Sshaped scan sequence combined with interlayer offset and orthogonal stagger mode can effectively eliminate the metallurgical defects and retained austenite within the produced SMCs.However,due to large thermal stress,microcracks that were perpendicular to the building direction formed within the SMCs.By employing the checkerboard filling(CBF)hatching mode,the thermal stress arising during SLM can be significantly reduced,thus preventing the evolution of interlayer microcracks.The compressive properties of fabricated SMCs can be tailored at a high compressive strength(~3031.5 MPa)and fracture strain(~24.8%)by adopting the CBF hatching mode combined with the optimized scan sequence and stagger mode.This study demonstrates great feasibility in tuning the mechanical properties of SLM-fabricated SMCs without varying the set energy input,e.g.,laser power and scanning speed. 展开更多
关键词 laser additive manufacturing selective laser melting scan strategy defect control mechanical property
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Composition control and temperature inferential control of dividing wall column based on model predictive control and PI strategies 被引量:2
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作者 Jianxin Wang Na Yu +2 位作者 Mengqi Chen Lin Cong Lanyi Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期1087-1101,共15页
The dividing wall column (DWC) is considered as a major breakthrough in distillation technology and has good prospect of industrialization. Model predictive control (MPC) is an advanced control strategy that has a... The dividing wall column (DWC) is considered as a major breakthrough in distillation technology and has good prospect of industrialization. Model predictive control (MPC) is an advanced control strategy that has acquired extensive applications in various industries. In this study, MPC is applied to the process for separating ethanol, n-propanol, and n-butanol ternary mixture in a fully thermally coupled DWC. Both composition control and tem- perature inferent/al control are considered. The multiobjective genetic algor/thm function "gamult/obj" in Matlab is used for the weight tuning of MPC. Comparisons are made between the control performances of MPC and PI strategies. Simulation results show that although both MPC and PI schemes can stabilize the DWC in case of feed disturbances, MPC generally behaves better than the PI strategy for both composition control and tempera- ture inferential control, resulting in a more stable and superior performance with lower values of integral of squared error (ISE). 展开更多
关键词 Dividing wall column Composition control Temperature inferential control PI strategy Model predictive control Genetic algorithm
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Refrigerant Control Strategies for Residential Air-Conditioning and Heat-Pump System 被引量:1
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作者 SU Shun-yu,ZHANG Chun-zhi,CHEN Jian(College of Urban Construction,Wuhan University of Science and Technology,Wuhan,Hubei 430070,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期91-95,共5页
This paper simulated the optimal refrigerant charge inventory of a refrigeration system in air-conditioning operation and heat-pump operation respectively,and studied the refrigerant control strategies in this system.... This paper simulated the optimal refrigerant charge inventory of a refrigeration system in air-conditioning operation and heat-pump operation respectively,and studied the refrigerant control strategies in this system.The void fraction in two-phase fluid region was calculated by Harms model.And based on distributed parameter model and Harms model,the refrigerant charge inventory in condenser and evaporator were calculated and analyzed in air-conditioning conditions and heat-pump conditions,respectively.The calculating results of different refrigerant mass between refrigeration and heating conditions indicate that the optimal refrigerant charge inventory in heat-pump conditions is lower than that in air-conditioning conditions.To avoid the decrease of COP due to the surplus refrigerant in heating conditions,we introduced the liquid reservoir control method and associate capillary control method.Both of them could increase the heating capacity of the air-source heat pump.The difference of optimal refrigerant charge inventory in air-conditioning and heat-pump system can be controlled by the liquid reservoir or the associate capillary. 展开更多
关键词 air-source HEAT PUMP control strategy distributed PARAMETER model CHARGE INVENTORY
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The Combination of Two Control Strategies for Series Hybrid Electric Vehicles 被引量:2
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作者 Can Luo Zhen Shen +2 位作者 Simos Evangelou Gang Xiong Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期596-608,共13页
With most countries paying attention to the environment protection, hybrid electric vehicles have become a focus of automobile research and development due to the characteristics of energy saving and low emission. Pow... With most countries paying attention to the environment protection, hybrid electric vehicles have become a focus of automobile research and development due to the characteristics of energy saving and low emission. Power follower control strategy(PFCS) and DC-link voltage control strategy are two sorts of control strategies for series hybrid electric vehicles(HEVs). Combining those two control strategies is a new idea for control strategy of series hybrid electric vehicles. By tuning essential parameters which are the defined constants under DClink voltage control and under PFCS, the points of minimum mass of equivalent fuel consumption(EFC) corresponding to a series of variables are marked for worldwide harmonized light vehicles test procedure(WLTP). The fuel economy of series HEVs with the combination control schemes performs better compared with individual control scheme. The results show the effects of the combination control schemes for series HEVs driving in an urban environment. 展开更多
关键词 DC-Link voltage control power follower control strategy series hybrid electric vehicles tuning
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Instantaneous Active and Reactive Power and Current Strategies for Current harmonics cancellation in 3-ph 4wire SHAF With both PI and Fuzzy Controllers 被引量:1
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作者 Suresh Mikkili Anup Kumar Panda 《Energy and Power Engineering》 2011年第3期285-298,共14页
Control strategies for extracting the three-phase reference currents for shunt active power filters are compared, evaluating their performance under different source conditions with PI and Fuzzy Controllers in MATLAB/... Control strategies for extracting the three-phase reference currents for shunt active power filters are compared, evaluating their performance under different source conditions with PI and Fuzzy Controllers in MATLAB/Simulink environment When the supply voltages are balanced and sinusoidal, the two control strategies are converge to the same compensation characteristics;However, the supply voltages are distorted and/or un-balanced sinusoidal, these control strategies result in different degrees of compensation in harmonics. The compensation capabilities are not equivalent, with p - q control strategy unable to yield an adequate solution when source voltages are not ideal. Extensive simulations are carried out with PI controller and also with Fuzzy controller for both p-q and Id-Iq control strategies under different main voltages. Extensive Simulations are carried out with PI as well as fuzzy controller for both p-q and Id - Iq control strategies by considering different voltage conditions and adequate results were presented. On owing Id - Iq method with fuzzy logic controller gives away an out-standing performance under any voltage conditions (balanced, un-balanced, balanced and non-sinusoidal). 展开更多
关键词 Harmonic Compensation Shunt ACTIVE Filter (SHAF) p-q control STRATEGY id-iq control STRATEGY PI controlLER and Fuzzy controlLER
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Optimization of operational strategies for rich gas enhanced oil recovery based on a pilot test in the Bakken tight oil reservoir
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作者 Xincheng Wan Lu Jin +4 位作者 Nicholas A.Azzolina Jin Zhao Xue Yu Steven A.Smith James A.Sorensen 《Petroleum Science》 SCIE EI CSCD 2023年第5期2921-2938,共18页
Horizontal well drilling and multistage hydraulic fracturing have been demonstrated as effective approaches for stimulating oil production in the Bakken tight oil reservoir.However,after multiple years of production,p... Horizontal well drilling and multistage hydraulic fracturing have been demonstrated as effective approaches for stimulating oil production in the Bakken tight oil reservoir.However,after multiple years of production,primary oil recovery in the Bakken is generally less than 10%of the estimated original oil in place.Gas huff‘n’puff(HnP)has been tested in the Bakken Formation as an enhanced oil recovery(EOR)method;however,most field pilot test results showed no significant incremental oil production.One of the factors affecting HnP EOR performance is premature gas breakthrough,which is one of the most critical issues observed in the field because of the presence of interwell fractures.Consequently,injected gas rapidly reaches adjacent production wells without contacting reservoir rock and increasing oil recovery.Proper conformance control is therefore needed to avoid early gas breakthrough and improve EOR performance.In this study,a rich gas EOR pilot in the Bakken was carefully analyzed to collect the essential reservoir and operational data.A simulation model with 16 wells was then developed to reproduce the production history and predict the EOR performance with and without conformance control.EOR operational strategies,including single-and multiple-well HnP,with different gas injection constraints were investigated.The simulation results of single-well HnP without conformance control showed that a rich gas injection rate of at least 10 MMscfd was needed to yield meaningful incremental oil production.The strategy of conformance control via water injection could significantly improve oil production in the HnP well,but injecting an excessive amount of water also leads to water breakthrough and loss of oil production in the offset wells.By analyzing the production performance of the wells individually,the arrangement of wells was optimized for multiple-well HnP EOR.The multiwell results showed that rich gas EOR could improve oil production up to 7.4%by employing conformance control strategies.Furthermore,replacing rich gas with propane as the injection gas could result in 14%of incremental oil production. 展开更多
关键词 Rich gas injection Bakken tight oil reservoir EOR strategies Conformance control Embedded discrete fracture model
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Structure and Control Strategies of Fuel Cell Vehicle 被引量:1
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作者 宋建国 张承宁 +1 位作者 孙逢春 钟秋海 《Journal of Beijing Institute of Technology》 EI CAS 2004年第1期63-66,共4页
The structure and kinds of the fuel cell vehicle (FCV) and the mathematical model of the fuel cell processor are discussed in detail. FCV includes many parts: the fuel cell thermal and water management, fuel supply, a... The structure and kinds of the fuel cell vehicle (FCV) and the mathematical model of the fuel cell processor are discussed in detail. FCV includes many parts: the fuel cell thermal and water management, fuel supply, air supply and distribution, AC motor drive, main and auxiliary power management, and overall vehicle control system. So it requires different kinds of control strategies, such as the PID method, zero-pole method, optimal control method, fuzzy control and neural network control. Along with the progress of control method, the fuel cell vehicle's stability and reliability is up-and-up. Experiment results show FCV has high energy efficiency. 展开更多
关键词 fuel cell proton-exchange-membrane control strategy
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Risk prevention and control strategies for the severely affected areas of snow disaster in the Three Rivers Source Region(TRSR), China 被引量:1
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作者 ShiJin Wang ShengYun Chen YanQiang Wei 《Research in Cold and Arid Regions》 CSCD 2019年第3期248-252,共5页
Historically,frequent and heavy snow disaster(SD)has caused serious livestock death and casualties,resulting in a devastating impact on animal husbandry development in the Three Rivers Source Region(TRSR).From winter ... Historically,frequent and heavy snow disaster(SD)has caused serious livestock death and casualties,resulting in a devastating impact on animal husbandry development in the Three Rivers Source Region(TRSR).From winter in 2018 to spring in 2019,the largest SD occurred in this area over the past 10 years,especially in core zones of the Lancang River Source Region.Field research results show that the main causes of the major SD include weak infrastructure(i.e.,roads,communications,warm sheds,and insufficient forage reserve),low rate of domestic animals for sale before the SD,and low loss settlement rate.SD occurrence could furtherly reduce the ability of disaster prevention,mitigation and relief of disaster loss.In the future,heavily affected SD areas should improve the forecasting ability of snowfall incidents,strengthen infrastructure construction,implement grass and livestock balance strategies,optimize livestock structure,improve loss settlement rate,and develop a modern compound model of animal husbandry development model that combines breeding,slaughtering and deep processing of animal product. 展开更多
关键词 THREE RIVERS Source Region SNOW DISASTER severely AFFECTED area risk prevention control strategy
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Analysis of Different Vibration Control Strategies for Soft Mounted Induction Motors with Sleeve Bearings Using Active Motor Foot Mounts 被引量:1
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作者 Ulrich Werner 《Journal of Applied Mathematics and Physics》 2019年第3期611-637,共27页
The paper presents a theoretical analysis of different vibration control strategies of soft mounted induction motors with sleeve bearings, using active motor foot mounts. After the vibration model is presented, differ... The paper presents a theoretical analysis of different vibration control strategies of soft mounted induction motors with sleeve bearings, using active motor foot mounts. After the vibration model is presented, different controllers in combination with different feedback strategies are mathematically investigated. The focus is here on the forced vibrations, caused by dynamic rotor eccentricity—rotor mass eccentricity, magnetic eccentricity and bent rotor deflection. After the mathematically coherences are described, a numerical example is shown, where the forced vibrations caused by bent rotor deflection are investigated, for different control strategies, where the mass matrix, the stiffness matrix and the damping matrix are influenced by different control parameters. The aim of the paper is to show the mathematically coherences and the possibility to influence the vibration behaviour, by different control strategies to optimize the vibration behaviour of soft mounted induction motors. 展开更多
关键词 ACTIVE Vibration control control strategies Induction MOTOR SOFT Foundation MOTOR FOOT Mounts
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