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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 debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation
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作者 Chang Yang Yong-bo Tie +3 位作者 Xian-zheng Zhang Yan-feng Zhang Zhi-jie Ning Zong-liang Li 《China Geology》 CAS CSCD 2024年第2期248-263,共16页
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff... Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events. 展开更多
关键词 Landslide Debris flow Hazard assessment Numerical simulation OpenLISEM prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully Sichuan province Geological hazards survey engineering
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Combustion mechanism and control approaches of underground coal fires:a review 被引量:3
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作者 Yuntao Liang Yalan Yang +2 位作者 Sida Guo Fuchao Tian Shaofeng Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第2期58-82,共25页
With the large-scale mining of coal resources,the huge economic losses and environmental problems caused by underground coal fires have become increasingly prominent,and the research on the status quo and response str... With the large-scale mining of coal resources,the huge economic losses and environmental problems caused by underground coal fires have become increasingly prominent,and the research on the status quo and response strategies of underground coal fires is of great significance to accelerate the green prevention and control of coal fires,energy conservation and emission reduction.In this paper,we summarized and sorted out the research status of underground coal fires,focused on the theoretical and technical issues such as underground coal fire combustion mechanism,multiphysics coupling effect of coal fire combustion,fire prevention and extinguishing technology for underground coal fires,and beneficial utilization technology,and described the latest research progress of the prevention and control for underground coal fire hazards.Finally,the key research problems in the field of underground coal fire hazards prevention and control were proposed in the direction of the basic theory,technology research,comprehensive management and utilization,with a view to providing ideas and solutions for the management of underground coal fires. 展开更多
关键词 Underground coal fire Combustion mechanism Multiphysics coupling effect Disaster prevention and control Turning harm into benefit Response strategy
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Control Effect of Bio-guide Wasp Virus Missile on Ostrinia furnacalis and Its Benefits for Maize Production in Nanchong City
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作者 彭昌家 白体坤 +8 位作者 丁攀 冯礼斌 尹怀中 龙维国 杨宇衡 杨建华 何海燕 苟建华 罗怀海 《Agricultural Science & Technology》 CAS 2016年第3期662-666,共5页
In order to promote "green plant protection", reduce the administration dosage and residue of pesticides and control cost of environment pollution, and improve maize production, quality and agricultural ecological e... In order to promote "green plant protection", reduce the administration dosage and residue of pesticides and control cost of environment pollution, and improve maize production, quality and agricultural ecological environment safety. In this study, the control effect and benefit of bio-guide wasp virus missile(BGWVM) on Ostrinia furnacalis in Nanchong City was investigated by using insect light traps and combined method of field investigation and experimental demonstration. According to the results, applying 30-37 pairs of BGWVM per hectare exhibited an average control efficiency of 78.0%, and the control cost was 139.50-172.50 CNY/hm2, which was reduced by 142.50-168.00 CNY/hm^2 compared with conventional chemical control. Average maize yield in BGWVM demonstration plot was 817.8 kg/hm2 higher and improved by 11.0% compared with blank control plot. The output value was improved by 1 799.16 CNY/hm^2 and the revenue increased by 1 941.66-1 967.16CNY/hm2. During 2003-2014, the cumulative demonstration and popularization area of BGWVM technique in Nanchong City had reached 24 507.33 hm^2, and the cumulative yield increment reached 20.042 1 million kg. BGWVM application improved total output value by 44.092 6 million CNY and saved control cost by 3.492 3-4.117 2 million CNY, thus increasing the revenue by 47.584 9-48.209 8 million CNY. BGWVM application reduced 551.41 t of 5% dimehypo GG or 12.87 t of 90%monosultap WP. In addition, BGWVM technique is simple to use, labor-saving and safe for human, animals, environment and crops, with significant economic, ecological and social benefits and without any side effect, which has become an ideal substitute for controlling O. furnacalis and reducing chemical pesticides in organic agriculture industry, modern agriculture industry, production of green and pollution-free agricultural products and IBM prevention and control demonstration gardens. 展开更多
关键词 Ostrinia furnacalis Bio-guide wasp virus missile prevention and control effect BENEFIT Evaluation
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Construction Technology and Safety Risk Control Measures of Deep Foundation Pit Excavation 被引量:1
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作者 Mingmin Jiang 《Journal of World Architecture》 2023年第2期24-29,共6页
Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example t... Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example to analyze deep foundation pit excavation technology,including the nature of this construction project,the main technical measures in the construction of deep foundation pit,and the analysis of the safety risk prevention and control measures.The purpose of this analysis is to provide scientific reference for the construction quality and safety of deep foundation pits. 展开更多
关键词 Construction engineering Deep foundation pit excavation Construction technology Risk prevention and control measures
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Effects of Different Herbicides on Maize Growth and Weed Control in Maize Fields 被引量:1
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作者 Yanyan CHEN Yang YANG +1 位作者 Jing ZHOU Guiyuan MENG 《Agricultural Science & Technology》 CAS 2017年第9期1738-1740,共3页
Effects of four herbicides(paraquat, acetochlor, nicosulfuron and atrazine) on the growth of maize and control effect of plant quantity and fresh weight of weeds were studied. The results showed that 15 days after spr... Effects of four herbicides(paraquat, acetochlor, nicosulfuron and atrazine) on the growth of maize and control effect of plant quantity and fresh weight of weeds were studied. The results showed that 15 days after spraying the herbicides on weeds,the prevention and control effect of paraquat on weeds was the optimum, and its effects on the plant quantity and fresh weight of weeds were above 81.57%; the prevention and control effect of acetochlor on weeds was the second best; the prevention and control effect of atrazine on weeds was the worst, and its effects on the plant quantity and fresh weight of weeds were only 51.04% and 37.86%. After 30 or 45 days, the prevention and control effect of atrazine and nicosulfuron on weeds in the maize fields was better than the other herbicides, and their effects on the plant quantity and fresh weight of weeds were higher than 70.00% and 85.00%. Acetochlor and paraquat had certain phytotoxicity to the growth of maize after about 15 days, and its leaves became yellow and grew slowly. On the whole, nicosulfuron had good prevention and control effect on weeds and had no phytotoxicity to the growth of maize. 展开更多
关键词 MAIZE HERBICIDES WEEDS GROWTH prevention and control effect
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Teaching Form Reform of "Prevention and Control of Poultry and Poultry Diseases" Course in Higher Vocational Colleges
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作者 OUYANG Qing-fang WEI Xiao-mei ZENG Xiao-hu 《Animal Husbandry and Feed Science》 CAS 2011年第3期45-48,共4页
[ Objective] To meet the needs of "Prevention and Control of Poultry and Poultry Diseases" course in higher vocational colleges in new period. [Method] In order to introduce theoretical knowledge, enhance practical ... [ Objective] To meet the needs of "Prevention and Control of Poultry and Poultry Diseases" course in higher vocational colleges in new period. [Method] In order to introduce theoretical knowledge, enhance practical ability and train quality, teaching content, teaching methods and practical teaching of the course were explored according to trends of academic development and personnel training. [ Result] The reform of teaching form improved the teaching effect, mobilized the learning enthusiasm and initiative of students, and enhanced their ability to solve practical prob- lems. [ Conclusion] The teaching form of "Prevention and Control of Poultry and Poultry Diseases" course has been successfully reformed. 展开更多
关键词 prevention and control of poultry and poultry diseases Teaching form Teaching effect
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Effects of policies and containment measures on control of COVID- 19 epidemic in Chongqing
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作者 Xiao-Hua Liang Xian Tang +2 位作者 Ye-Tao Luo Min Zhang Ze-Pei Feng 《World Journal of Clinical Cases》 SCIE 2020年第14期2959-2976,共18页
BACKGROUND Coronavirus disease 2019(COVID-19)is an emerging,rapidly evolving disease that spreads through the respiratory system and is highly contagious.In March 2020,the World Health Organization declared the COVID-... BACKGROUND Coronavirus disease 2019(COVID-19)is an emerging,rapidly evolving disease that spreads through the respiratory system and is highly contagious.In March 2020,the World Health Organization declared the COVID-19 outbreak a pandemic.In China,the pandemic was controlled after 2 mo through effective policies and containment measures.Describing the detailed policies and containment measures used to control the epidemic in Chongqing will provide a reference for the prevention and control of COVID-19 in other areas of the world.AIM To explore the effects of different policies and containment measures on the control of the COVID-19 epidemic in Chongqing.METHODS Epidemiological data on COVID-19 in Chongqing were prospectively collected from January 21 to March 15,2020.The policies and prevention measures implemented by the government during the epidemic period were also collected.Trend analysis was performed to explore the impact of the main policy measures on the effectiveness of the control of COVID-19 in Chongqing.As of March 15,the cumulative incidence of COVID-19 in Chongqing was 1.84/100000(576 cases)and the infection fatality rate was 1.04%(6/576).The spread of COVID-19 was controlled by effective policies that involved establishing a group for directing the COVID-19 epidemic control effort;strengthening guidance and supervision;ensuring the supply of daily necessities and medical supplies and equipment to residents;setting up designated hospitals;implementing legal measures;and enhancing health education.Medical techniques were implemented to improve the recovery rate and control the epidemic.Policies such as“the lockdown of Wuhan”,“initiating a first-level response to major public health emergencies”,and“implementing the closed management of residential communities”significantly curbed the spread of COVID-19.Optimizing the diagnosis process,shortening the diagnosis time,and constructing teams of clinical experts facilitated the provision of“one team of medical experts for each patient”treatment for severe patients,which significantly improved the recovery rate and reduced the infection fatality rate.CONCLUSION The prevention policies and containment measures implemented by the government and medical institutions are highly effective in controlling the spread of the epidemic and increasing the recovery rate of COVID-19 patients. 展开更多
关键词 prevention policies Containment measures COVID-19 Epidemic trend control effectiveness Public health
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Introduction of New Method on Engineering Risk Assessment:Engineering Errors and Effects Analysis(3EA)
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作者 Mohammad Mahdi Izadi 《Management Studies》 2018年第6期527-530,共4页
Construction and commissioning accidents investigation shows that engineer’s errors in basic and detailed phases are the main causes.It will be gained more efficiency of investment when a relevant method is applied f... Construction and commissioning accidents investigation shows that engineer’s errors in basic and detailed phases are the main causes.It will be gained more efficiency of investment when a relevant method is applied for error identification and risk assessment in basic and detailed phases.Most of risk assessment methods are related to construction phase,meanwhile hidden risks that were happen in previous phases cannot be found by these methods.Although HAZOP study can be applied in detail phase but it can help to find process defections.Importance of identifying risks in basic and detailed phases is to apply preventive actions against birth and grows risks.This risk assessment method can reduce costs and improve environmental protection,safety,and reliability of designs.The main purpose of this study is to identify engineer’s errors and analyse their HSE effects.The method is applied in seven oil and gas engineering projects in Iran,raising the level of engineer’s attention to safety precautions and environmentally-friendly design,reducing the cost of improving the level of safety and environmental protection,improving environmental protection,safety,and design reliability,and improving procedures related to design process and control have been achieved. 展开更多
关键词 engineering ERRORS and effectS Analysis(3EA) engineering error detailed effectIVENESS control risk assessment
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Research on Prevention and Control of Environmental Pollution in Building Construction
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作者 Zeyuan Wang 《Journal of Architectural Research and Development》 2019年第2期5-8,共4页
The quality of human life has been greatly improved with the rapid development of the market economy.However,at the same time,people are paying more attention to the problems caused by environmental pollution.As a res... The quality of human life has been greatly improved with the rapid development of the market economy.However,at the same time,people are paying more attention to the problems caused by environmental pollution.As a result,there is an increase in environmental awareness.At the present stage,people are concerned about the negative impact that building construction has on the environment.Building construction enterprises must have preventive measures and deal with environmental pollution during construction.This is to minimize pollution caused by construction and to satisfy the implementation of green civilization construction.This is important as it can enhance the development of socialist spiritual civilization and thus promote the expansion of enterprises in the long run.The author explores and analyzes the main types of environmental pollution generated in building construction.Besides,the author provides effective measures for the prevention and control of environmental pollution caused by building construction to reduce its adverse impact on the environment. 展开更多
关键词 BUILDING construction ENVIRONMENTAL POLLUTION prevention and control effectIVE measures
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Early filiform needle acupuncture for poststroke depression: a meta-analysis of 17 randomized controlled clinical trials 被引量:12
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作者 Jiping Zhang Jing Chen +4 位作者 Junqi Chen Xiaohui Li Xueyan Lai Shaoqun Zhang Shengxu Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第7期773-784,共12页
OBJECTIVE: To evaluate the effectiveness and safety of filiform needle acupuncture for poststroke depression, and to compare acupuncture with the therapeutic efficacy of antidepressant drugs. DATA RETRIEVAL: We retr... OBJECTIVE: To evaluate the effectiveness and safety of filiform needle acupuncture for poststroke depression, and to compare acupuncture with the therapeutic efficacy of antidepressant drugs. DATA RETRIEVAL: We retrieved data from the Chinese National Knowledge Infrastructure (1979-2012), Wanfang (1980-2012), VIP (1989-2012), Chinese Biomedical Literature (1975- 2012), PubMed (1966-2012), Ovid Lww (-2012), and Cochrane Library (-2012) Database using the internet. SELECTION CRITERIA: Randomized controlled trials on filiform needle acupuncture versus antidepressant drugs for treatment of poststroke depression were included. Moreover, the in- cluded articles scored at least 4 points on the Jadad scale. Exclusion criteria: other acupuncture therapies as treatment group, not stroke-induced depression patients, score 〈 4 points, non-ran- domized controlled trials, or animal trials. MAIN OUTCOME MEASURES: These were the Hamilton Depression Scale scores, clinical ef- fective rate, Self-Rating Depression Scale scores, Side Effect Rating Scale scores, and incidence of adverse reaction and events. RESULTS: A total of 17 randomized controlled clinical trials were included. Meta-analysis results displayed that after 4 weeks of treatment, clinical effective rate was better in patients treated with fill- form needle acupuncture than those treated with simple antidepressant drugs [relative risk = 1.11, 95% confidence interval (C/): 1.03-1.21, P = 0.01]. At 6 weeks, clinical effective rate was similar between filiform needle acupuncture and antidepressant drug groups. At 2 weeks after filiform needle acupuncture, Hamilton Depression Scale (17 items) scores were lower than in the antide- pressant drug group (mean difference = -2.34, 95%CI: -3.46 to -1.22, P 〈 0.000,1). At 4 weeks, Hamilton Depression Scale (24 items) scores were similar between filiform needle acupuncture and antidepressant drug groups. Self-Rating Depression Scale scores were lower in filiform needle acupuncture group than in the antidepressant drug group. Side Effect Rating Scale was used in only two articles, and no meta-analysis was conducted. Safety evaluation of the 17 arti- cles showed that gastrointestinal tract reactions such as nausea and vomiting were very common in the antidepressant drug group. Incidence of adverse reaction and events was very low in the filiform needle acupuncture group. CONCLUSION: Early filiform needle acupuncture for poststroke depression can perfectly con- trol depression. Filiform needle acupuncture is safe and reliable. Therapeutic effects of filiform needle acupuncture were better than those of antidepressant drugs. 展开更多
关键词 nerve regeneration poststroke depression filiform needle acupuncture antidepressantdrugs randomized controlled trials clinical effective rate SAFETY META-ANALYSIS the GuangdongProvincial "211 engineering Stage-III Key Disciplines Construction Project neural regeneration
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Hydrogeological Hazards and Control Measures in Engineering Geological Exploration
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作者 Pengna Zhou 《Journal of Geological Research》 2019年第1期46-49,共4页
For engineering geological investigation, hydrographic surveys are particularly important. By operating the equipment, relevant technicians analyze hydrogeological data around the project. A series of corresponding me... For engineering geological investigation, hydrographic surveys are particularly important. By operating the equipment, relevant technicians analyze hydrogeological data around the project. A series of corresponding measures were taken to ensure the smooth completion of the project. However, due to the inadequate completion of hydrogeological survey work, it has great harm to the later stage of engineering work, and even will lead to the final failure of the project. Based on this, this paper explores the hazards and prevention measures of hydrogeology in engineering surveys. 展开更多
关键词 engineering INVESTIGATION HYDROGEOLOGY PROBLEMS Hazards prevention and control measures
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Experimental study on mechanism and protection of stress ulcer produced by explosive noise 被引量:13
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作者 LIU Guo Shi 1, HUANG Yu Xin 1, LI Shuan Wei 2, PAN Bo Rong 3, WANG Xin 1, SUN Da Yong 1 and WANG Qing Li 1 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第6期64-68,共5页
AIM To establish an experimental model of stress ulcer produced by explosive noise, and to probe into its mechanism and protection. METHODS The country standard Wistar white rats were randomly divided into control ... AIM To establish an experimental model of stress ulcer produced by explosive noise, and to probe into its mechanism and protection. METHODS The country standard Wistar white rats were randomly divided into control group ( n =8), which were neither stimulated nor protected, and stimulating group (divided into subgroups A, B and C, including 8 rats each which were decapitated to draw blood for test immediately, 12 hours and 24 hours after stimulation) and prevention group (divided into subgroups A, B and C, having 8 rats each, subgroup A was given cimetidine, B anisodamine and C both drugs). Firing noises of submachine guns were used as inflicting factor. The rats were fasted for 24 hours and stimulated by firing noise for 12 hours. The change of ulcer index, gastric mucosal and related serum hormones were observed. RESULTS Stress ulcer was significant in the stimulating group, and its ulcer index (8 6±0 6) was remarkably higher than that in both the control group and prevention group (0 3±0 1, P <0 01). Its serum gastrin (Gas ng/L , 294±163 vs 63±40, P <0 01) and endothelin (ET ng/L , 181±57 vs 135±42, P <0 01) were apparently higher than those in the control group, and its serum nitric oxide (NO) level was conspicuously lower than that in the control group ( ng/L , 0 2±0 1 vs 0 8±0 5, P <0 05), while the serum gastrin level ( ng/L , 556±225) in prevention group was distinctly higher than that in both the control ( P <0 01) and stimulating group ( P <0 05). There were no significant differences in the changes of ET and NO between the control and the stimulating groups. CONCLUSION Stress ulcer model of rats can be successfully established by the stimulation of explosive noise. Gas, ET and NO are related to the formation of stress ulcer, and play an important role in its mechanism. Hepatic function affected by noise is observed in this experiment. 展开更多
关键词 STOMACH ulcer/etiology STOMACH ulcer/prevention and control gastric mucosa/pathology noise/adverse effects STRESS ULCER
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Auto-updating model-based control for thrust variation mitigation and acceleration performance enhancement of gas turbine aero-engines
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作者 Zhiyuan Wei Shuguang Zhang 《Propulsion and Power Research》 SCIE 2024年第3期394-415,共22页
Model-based control shows promising potential for engine performance improve-ment and future aero-propulsion requirements.In this paper,an auto-updating thrust variation mitigation(AuTVM)control approach using on-boar... Model-based control shows promising potential for engine performance improve-ment and future aero-propulsion requirements.In this paper,an auto-updating thrust variation mitigation(AuTVM)control approach using on-board model strategies is proposed for gas tur-bine aero-engines under in-service degradation effects,which aims at active thrust regulation and acceleration protection in a simultaneous way.The AuTVM control is integrated with an on-line block,based on a reliable on-board engine model,and an off-line part for the periodical update of control parameters via post-flight engine monitoring data.The core feature of the AuTVM control is a set of auto-updating loops within the on-line part,including thrust regu-lation loop,surge margin loop,turbine entry temperature loop,and the steady loop,whose con-trol parameters are periodically adjusted with increasingflight cycles.Meanwhile,an industrial sensor-based baseline controller and two tailored model-based controllers,i.e.,a thrust variation mitigation(TVM)controller withfixed gains and a self-enhancing active transient protection(SeATP)controller with pro-active transient protection and passive thrust control,are also developed as comparison bases.Numerical simulations for idle to full-power acceleration tests are carried on a validated aero-thermal turbofan engine model using publicly available degra-dation data.Simulation results demonstrate that both new engines and severely degraded en-gines regulated by the AuTVM controller show significant thrust response enhancement,compared to the baseline controller.Moreover,thrust variation at the maximum steady state of degraded engines,which exists within the SeATP controller and the baseline controller,is suppressed by the proposed AuTVM controller.Robustness analysis against degradation uncer-tainties and sensor accuracy confirms that the AuTVM controller owns a closer maximum steady-state thrust distribution to the desired value than those of the SeATP and the baseline controller while utilizing transient margins of controlled engines more effectively.Hence,the control performance of the AuTVM controller for in-service engines is guaranteed. 展开更多
关键词 Gas turbine aero-engines Auto-updating thrust variation mitigation Active transient protection Model-based control Engine performance improvement Degradation effects
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Analysis and Research of Ice Loads Acting on Offshore Structures 被引量:1
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作者 Ji, Chunqun 《China Ocean Engineering》 SCIE EI 1993年第2期167-176,共10页
Usually, the action of sea ice on offshore engineering structures is one of the controlling loads in cold waters engineering structure design. The reasonable selection of environmental condition and the physical mecha... Usually, the action of sea ice on offshore engineering structures is one of the controlling loads in cold waters engineering structure design. The reasonable selection of environmental condition and the physical mechanical properties of ice in the region are directly related to the structure design, operation and safety. In this paper, the sea ice force acting on the structure, the physical mechanical properties of ice and the selection of parameters in calculation are discussed. Some suggestions are proposed as to the calculation of various kinds of ice loads acting on the structure. 展开更多
关键词 Accident prevention Arctic engineering CALCULATIONS Dynamic loads Finite element method Ice control Mechanical properties offshore structures Physical properties Structural design
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Key technologies and practice for gas field storage facility construction of complex geological conditions in China 被引量:6
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作者 MA Xinhua ZHENG Dewen +3 位作者 SHEN Ruichen WANG Chunyan LUO Jinheng SUN Junchang 《Petroleum Exploration and Development》 2018年第3期507-520,共14页
In view of complex geological characteristics and alternating loading conditions associated with cyclic large amount of gas injection and withdrawal in underground gas storage(UGS) of China, a series of key gas storag... In view of complex geological characteristics and alternating loading conditions associated with cyclic large amount of gas injection and withdrawal in underground gas storage(UGS) of China, a series of key gas storage construction technologies were established, mainly including UGS site selection and evaluation, key index design, well drilling and completion, surface engineering and operational risk warning and assessment, etc. The effect of field application was discussed and summarized. Firstly, trap dynamic sealing capacity evaluation technology for conversion of UGS from the fault depleted or partially depleted gas reservoirs. A key index design method mainly based on the effective gas storage capacity design for water flooded heterogeneous gas reservoirs was proposed. To effectively guide the engineering construction of UGS, the safe well drilling, high quality cementing and high pressure and large flow surface injection and production engineering optimization suitable for long-term alternate loading condition and ultra-deep and ultra-low temperature formation were developed. The core surface equipment like high pressure gas injection compressor can be manufactured by our own. Last, the full-system operational risk warning and assessment technology for UGS was set up. The above 5 key technologies have been utilized in site selection, development scheme design, engineering construction and annual operations of 6 UGS groups, e.g. the Hutubi UGS in Xinjiang. To date, designed main indexes are highly consistent with actural performance, the 6 UGS groups have the load capacity of over 7.5 billion cubic meters of working gas volume and all the storage facilities have been running efficiently and safely. 展开更多
关键词 gas field STORAGE trap dynamic SEALING capacity key index design effective STORAGE volume drilling and COMPLETION in ultra-deep and ultra-low pressure formation ALTERNATING load surface engineering core equipment risk assessment and control
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高速公路风险防控设施应用研究综述与展望 被引量:4
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作者 李海舰 刘中华 +2 位作者 陈开群 齐建宇 赵晓华 《交通运输工程与信息学报》 2024年第1期54-78,共25页
高速公路风险防控设施的合理应用能够显著降低交通运行风险。本文首先针对高速公路风险防控设施的研究现状进行了回顾与总结,将高速公路风险防控设施划分为非电气化防控设施和电气化防控设施。其次,归纳了高速公路非电气化和电气化防控... 高速公路风险防控设施的合理应用能够显著降低交通运行风险。本文首先针对高速公路风险防控设施的研究现状进行了回顾与总结,将高速公路风险防控设施划分为非电气化防控设施和电气化防控设施。其次,归纳了高速公路非电气化和电气化防控设施在风险防控中的作用以及研究中的关键问题,讨论了不同电气化风险防控设施的应用场景及其效用。然后,对由电气化设施构成的风险防控系统在多种典型场景中的应用效果进行了分析。最后,对高速公路风险防控设施应用综述结果及未来发展情况进行了总结。文献综述结果表明,高速公路风险防控设施和系统在不同场景中均能起到积极的效果;非电气化防控设施受限于自身物理特性,在应对动态信息发布和主动性、针对性风险防控上存在一定的不足;电气化风险防控设施以及风险防控系统的应用越来越广泛,对交通拥堵、不良天气等交通风险的防控愈加完善。同时,日渐成熟的车路协同技术和不断发展的智慧公路系统也是未来保障高速公路交通安全的重要一环。本文的研究成果可在一定程度上为今后高速公路风险防控设施的选型、设置及应用提供一定的借鉴。 展开更多
关键词 交通工程 风险防控技术 高速公路 交通标志标线 交通安全设施 研究综述
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考虑采动效应的闭坑矿井水硫酸盐污染规律 被引量:2
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作者 齐跃明 周沛 +3 位作者 周来 蒋丹 杨雨晴 刘延卓 《煤田地质与勘探》 EI CAS CSCD 北大核心 2024年第4期89-100,共12页
高硫煤矿闭坑后成为埋藏在地表以下深部的产酸污染场,对相邻含水层和周边环境造成了潜在危害,且因采动效应影响和矿井空间分布复杂导致相邻含水层的污染过程与污染程度评价困难。以某闭坑矿区为研究对象,选取SO_(4)^(2-)作为特征污染物... 高硫煤矿闭坑后成为埋藏在地表以下深部的产酸污染场,对相邻含水层和周边环境造成了潜在危害,且因采动效应影响和矿井空间分布复杂导致相邻含水层的污染过程与污染程度评价困难。以某闭坑矿区为研究对象,选取SO_(4)^(2-)作为特征污染物,考虑多煤层采动裂隙对含水层结构的破坏影响,运用数值模拟技术对闭坑矿区酸性矿井水中SO_(4)^(2-)污染迁移特征进行研究,并分析流体扩散系数对含水层污染物运移的影响。结果表明:SO_(4)^(2-)在二叠系童子岩组砂岩含水层中水平迁移面积随时间增大而增大,增大速率逐渐减小,垂向渗透系数扩大10倍,空间变异性增强;闭坑5、10、15a后,最大水平迁移距离分别为215、414、612m,最大垂向迁移距离分别达到50、65、70m;而扩散系数越大,产酸时间越长,SO_(4)^(2-)迁移距离和污染范围将随之增大,相较于水平方向,垂向上SO_(4)^(2-)浓度变化对扩散系数的敏感度更高。基于模拟结果,结合闭坑矿区实际条件,针对性提出了“源头减量-过程阻断-末端治理”的综合防控与治理方案。研究结果将为该闭坑煤矿酸性矿井水污染治理与防控提供理论基础,也为其他同类矿井提供科学借鉴。 展开更多
关键词 闭坑煤矿 酸性矿井水 硫酸盐 导水裂隙带 采动效应 综合防控
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10种杀虫剂对桃小食心虫防治效果评价
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作者 吐尔逊·阿合买提 刘旭坤 +8 位作者 赵雯慧 朱晓峰 阿尔孜姑丽·肉孜 帕丽达姆·塔依尔 付开赟 丁新华 贾尊尊 阿地力·沙塔尔 郭文超 《新疆农业科学》 CAS CSCD 北大核心 2024年第6期1447-1453,共7页
【目的】研究不同杀虫剂对桃小食心虫Carposina sasakii Matsmur的防治效果,筛选环境友好型农药和施药量,为有效控制桃小食心虫的发生与危害提供科学依据。【方法】选择10种新型杀虫剂2022年采用田间小区药效试验,比较不同杀虫剂的防治... 【目的】研究不同杀虫剂对桃小食心虫Carposina sasakii Matsmur的防治效果,筛选环境友好型农药和施药量,为有效控制桃小食心虫的发生与危害提供科学依据。【方法】选择10种新型杀虫剂2022年采用田间小区药效试验,比较不同杀虫剂的防治效果。【结果】10种处理药后7 d防效均较好,处理间无显著性差异(P>0.05),其中10%联苯·氟酰脲悬浮剂、1%苦参碱可溶液剂和12%甲维·虫螨腈悬浮剂,在药剂稀释倍数药后14 d,防效均能达到93.33%以上,1%苦参碱可溶液剂在药后21 d各所有处理区防治效果均在90.00%以上,不同药剂之间在药后14~21 d防治效果有一定波动。【结论】参试10种药剂各处理区药后7 d对桃小食心虫均具有显著的防治效果,其中1%苦参碱可溶液剂、10%联苯·氟酰脲悬浮剂和12%甲维·虫螨腈悬浮剂,施药后14 d防治效果表现优异,可在生产实践中使用。 展开更多
关键词 杀虫剂 桃小食心虫 防治效果 蛀果率
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地下工程防灾减灾课程案例库建设探讨
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作者 刘佳佳 许艳之 +3 位作者 杨明 李波 张学博 王丹 《高教学刊》 2024年第20期67-70,共4页
实现案例与理论的有机融合已经越发成为各课程教学方式的发展趋势,建立地下工程防灾减灾案例库,进行案例分析,将有助于改革课程模式,提高教学效率,促进该课程向前发展。基于文献分析,结合时代特征,对案例教学法在地下工程防灾减灾课程... 实现案例与理论的有机融合已经越发成为各课程教学方式的发展趋势,建立地下工程防灾减灾案例库,进行案例分析,将有助于改革课程模式,提高教学效率,促进该课程向前发展。基于文献分析,结合时代特征,对案例教学法在地下工程防灾减灾课程上的应用必要性进行探讨,重构课程教学目标,结合互联网和生活生产实际,对地下工程灾害案例进行挖掘,以河南理工大学安全专业为例,通过问卷调查对地下工程防灾减灾案例教学的实施效果进行评价,通过建立地下工程防灾减灾案例库,将案例与相关理论相结合,符合现代教学模式改革需要,值得提倡和进一步发展,所建立的案例库包含近期发生的地下工程水灾火灾事故案例及地下工程施工方法案例,案例教学法在地下工程防灾减灾课程上的应用得到广大学生的肯定,并给出积极评价。 展开更多
关键词 地下工程 防灾减灾 案例教学 教学改革 效果评价
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