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Resilience of metro systems subjected to external disturbances:A state-of-the-art review
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作者 Hao Bai Dong-Ming Zhang +4 位作者 Jian-Min Guo Yu-Shan Hua Bilal MAyyub Hong-Wei Huang Enrico Zio 《Resilient Cities and Structures》 2025年第4期72-96,共25页
Metro systems are important transport infrastructures in megacities,and their long-term operational safety is challenged by frequent external disturbances,such as environmental extremes and human construction activ-it... Metro systems are important transport infrastructures in megacities,and their long-term operational safety is challenged by frequent external disturbances,such as environmental extremes and human construction activ-ities.A metro system must be resilient to resist,adapt to,and recover its performance when such disruptions occur.Current studies on metro system resilience often lack a comprehensive view from a complex system perspective,leading to a plethora of choices for methods of analysis and indicators applied to different metro systems and external disturbances.Therefore,the present paper aims to provide a comprehensive review of the topics and works revolving around the resilience of metro systems.It first clarifies the concept of metro system resilience based on classical definitions from a technical perspective.Metro resilience encompasses both the structural and operational aspects of metro systems,including their damage mechanisms,analysis methods and indicators of resilience.Methods for enhancing metro system resilience across structural,operational and monitoring dimensions are explored.Finally,future research directions are discussed,emphasizing the impor-tance of considering the"system of systems"formed by interdependent infrastructure,refining uncertainty analysis,and investigating the opportunities arising from the application of artificial intelligence for improving metro system resilience against external disturbances. 展开更多
关键词 Metro system external disturbance Natural hazards Human-caused threats RESILIENCE
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Photocatalytic Membrane Filtration:Materials,System Optimization,and External Field Enhancement
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作者 Xianyuan Sun Jie Tian +7 位作者 Jiayang Cai Yanjie Wang Tao He Xiaoqing Qiu Zibiao Li Zuofang Yao Detlef W.Bahnemann Jiahong Pan 《Energy & Environmental Materials》 2025年第4期142-156,共15页
Photocatalytic membranes hold significant potential for promoting pollutant degradation and reducing membrane fouling in filtration systems.Although extensive research has been conducted on the independent design of p... Photocatalytic membranes hold significant potential for promoting pollutant degradation and reducing membrane fouling in filtration systems.Although extensive research has been conducted on the independent design of photocatalysts or membrane materials to improve their catalytic and filtration performance,the complex structures and interface mechanisms,as well as insufficient light utilization,are still often overlooked,limiting the overall performance improvement of photocatalytic membranes.This work provides an overview of enhancement strategies involving restricted area effects,external fields,such as mechanical,magnetic,thermal,and electrical fields,as well as coupling techniques with advanced oxidation processes(e.g.,O_(3),Fenton,and persulfate oxidation)for dual enhancement of photocatalysts and membranes.In addition,the synthesis method of photocatalytic membranes and the influence of factors,such as light source type,frequency,and relative position on photocatalytic membrane performance were also studied.Finally,economic feasibility and pollutant removal performance were further evaluated to determine the promising enhancement strategies,paving the way for more efficient and scalable applications of photocatalytic membranes. 展开更多
关键词 external field enhancement membrane filtration photocatalytic materials semiconductor photo(electro)catalysis water purification
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External application of traditional Chinese medicine in combination with threestep analgesic ladder therapy for cancer-induced bone pain:a systematic review and meta-analysis
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作者 Fei WANG Guihua LAI +4 位作者 Fang ZHOU Duorui NIE Xiongtao CHENG Yue WANG Jianxiong CAO 《Digital Chinese Medicine》 2025年第1期59-75,共17页
Objective To systematically evaluate the overall efficacy of external application of traditional Chinese medicine(EA-TCM)in combination with oral three-step analgesic ladder therapy for patients suffering from cancer-... Objective To systematically evaluate the overall efficacy of external application of traditional Chinese medicine(EA-TCM)in combination with oral three-step analgesic ladder therapy for patients suffering from cancer-induced bone pain(CIBP).Methods We conducted a literature search of randomized controlled trials on the combination of EA-TCM and three-step analgesic ladder therapy for CIBP across ten databases and two registration systems.It included four Chinese databases[Chinese Biomedical Literature Database(SinoMed),China National Knowledge Infrastructure(CNKI),Wanfang Database,and China Science and Technology Journal Database(VIP)],six English databases(Scopus,Embase,Web of Science,PubMed,Cochrane Library,and OpenGrey),and two registration systems(Chinese Clinical Trial Registry and ClinicalTrials.gov).The timeframe for the literature search extended from the inception of each database to December 31,2023.Meta-analysis was performed using RevMan(v5.4.1),and the outcome indicators(pain relief rate,analgesic duration,quality of life,pain intensity,breakthrough pain frequency,and adverse reactions)were graded using GRADE profiler(v3.6).Results According to the established inclusion and exclusion criteria,a total of 43 studies was deemed eligible,involving 3142 participants with CIBP.The results of meta-analysis showed that compared with oral three-step analgesic ladder therapy alone,the combined therapy of EA-TCM and three-step analgesic ladder has a significant improvement in pain relief rate[risk ratio(RR)=1.32,95%confidence interval(CI):1.24 to 1.41,P<0.00001],analgesic duration[mean difference(MD)=1.33,95%CI:0.97 to 1.69,P<0.00001],and quality of life(MD=5.66,95%CI:4.88 to 6.44,P<0.00001).Furthermore,the combined therapy significantly reduced pain intensity(MD=-1.00,95%CI:-1.19 to-0.80,P<0.00001),breakthrough pain frequency(MD=-0.43,95%CI:-0.51 to-0.36,P<0.00001),and adverse reactions(RR=0.60,95%CI:0.53 to 0.68,P<0.00001)in CIBP patients.Based on the GRADE assessment,the level of evidence varied from low to moderate.Conclusion EA-TCM combined with the three-step analgesic ladder therapy can effectively alleviate pain symptoms in patients with CIBP and improve their quality of life.Additionally,the EA-TCM can effectively reduce the incidence of adverse reactions associated with threestep analgesic therapy. 展开更多
关键词 external application of traditional Chinese medicine(EA-TCM) Three-step analgesic ladder therapy Cancer-induced bone pain(CIBP) systematic review META-ANALYSIS
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A novel external online calibration system for polarization detection
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作者 Li Zishuo He Honghui Wu Jian 《Journal of Innovative Optical Health Sciences》 2025年第5期33-44,共12页
In clinical environments,the prolonged utilization of polarization equipment can result in theaccumulation of errors over extended periods.The absence of expeditious calibration techniques in clinical practice present... In clinical environments,the prolonged utilization of polarization equipment can result in theaccumulation of errors over extended periods.The absence of expeditious calibration techniques in clinical practice presents a significant obstacle in preserving the precision and dependability of these instruments.To address this challenge,we propose an innovative research study that presents a comprebersive calibration system specifically designed for the calibration of the backscattering Muellet matrix measurement system,enabling swift online calibration acroes various scenarios.This system employs an external calibration framework for rmal-time adjust-ment of the polarizer's initial angle,oversecing the rotation of PSG and PSA motors through position measurement and control procedures,with light intensity monitored by a camera.By incorporating moment um concepts and the Adam optimization algorithm,we enhance conver-gence speed,mitigate noise,and improve calibration accuracy.Experimental results showcase the exceptional precision,speed,and robustness of oрroposed method,achieving high acсuracy and minimal error,thereby offering a promising solution for maintaining the reliabilit y of polarization equipment in clinical settings. 展开更多
关键词 DOTP external calibration system polarization detection
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Study on the Intervention of Renal Yang Deficiency Hypertension by Combined External Therapies of Traditional Chinese Medicine Through Regulating the RASS System
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作者 Chongquan Wang Jing Ao +3 位作者 Yuanyuan Tian Jun Zhang Rong Fan Zhanxiu Zhang 《Journal of Clinical and Nursing Research》 2025年第6期279-285,共7页
Objective:This study explores the mechanism and clinical efficacy of combined external therapies of traditional Chinese medicine(such as moxibustion,acupoint application,etc.)in intervening renal Yang deficiency hyper... Objective:This study explores the mechanism and clinical efficacy of combined external therapies of traditional Chinese medicine(such as moxibustion,acupoint application,etc.)in intervening renal Yang deficiency hypertension through regulating the renin-angiotensin-aldosterone system(RASS).Methods:Sixty-one patients with renal Yang deficiency hypertension admitted to the hospital were selected as the study subjects.They were divided into a Western medicine combined with external therapies of traditional Chinese medicine group(n=30)and a conventional Western medicine treatment group(n=31)based on a random number table method.The enrollment information,blood pressure changes,and differences in aldosterone,angiotensin II,and renin activity during follow-up were compared between the two groups.Results:There were no statistically significant differences in gender,past history,pre-study medication,hypertension grading,aldosterone,angiotensin II,renin activity levels,and blood pressure between the two groups at baseline(P>0.05).Aldosterone,angiotensin II,and renin activity levels were significantly reduced in both groups after treatment compared to pre-treatment levels.Moreover,the aldosterone,angiotensin II,and renin activity levels in the Western medicine combined with external therapies of traditional Chinese medicine group were significantly lower than those in the conventional Western medicine treatment group,with statistically significant differences(P<0.05).Conclusion:Western medicine combined with external therapies of traditional Chinese medicine may regulate the RASS system through multiple targets,restoring renal Yang Qi transformation function and providing a new strategy for the integrated treatment of renal Yang deficiency hypertension with Chinese and Western medicine. 展开更多
关键词 Combined external therapies of traditional Chinese medicine RASS system Renal Yang deficiency hypertension
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Controlling externally solidified crystals and porosity for enhancing mechanical properties of a die-casting aluminum-silicon alloy
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作者 Yi-hui Zhang Xiang-yi Jiao +6 位作者 Peng-yue Wang Yi-xian Liu Jin-rui Wang Wen-ning Liu Li-jun Shi Cheng-gang Wang Shou-mei Xiong 《China Foundry》 2026年第1期94-100,共7页
The effects of the high pressure die casting(HPDC)processes on porosity,microstructure,and mechanical properties of heat-treatment-free aluminum silicon(Al-Si)alloys have long been a focal point in automotive die-cast... The effects of the high pressure die casting(HPDC)processes on porosity,microstructure,and mechanical properties of heat-treatment-free aluminum silicon(Al-Si)alloys have long been a focal point in automotive die-casting research.In this work,the combined effect of shot sleeve materials and slow shot speeds on porosity,microstructure and mechanical properties of a newly designed HPDC Al-Si alloy was investigated.Results show that employing a ceramic shot sleeve or increasing the slow shot speed significantly reduces both the average size and area fraction of externally solidified crystals(ESCs),as well as the average pore size and volume fraction.When the slow shot speed is increased from 0.05 m·s^(-1)to 0.1 m·s^(-1),the pore volume fraction decreases by 10.2%in steel-shot-sleeve samples,compared to a substantial 67.1%reduction in ceramic-shot-sleeve samples.At a slow shot speed of 0.1 m·s^(-1),castings produced with a ceramic shot sleeve exhibit superior mechanical properties:8.3%higher yield strength,17.4%greater tensile strength,and an 81.4%improvement in elongation,relative to those from a steel shot sleeve.These findings provide valuable insights for minimizing porosity and coarse ESCs in die castings,offering promising potential for broader industrial applications. 展开更多
关键词 high pressure die casting aluminum-silicon alloy externally solidified crystals POROSITY shot sleeve
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System Design for Urban Forest Park——Based on Elimination of Externality during Development and Tourism Process
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作者 付亚菲 《Journal of Landscape Research》 2011年第4期72-75,共4页
The paper had introduced researches on urban forest park and analyzed its particularity.In terms of elimination of externality during development and tourism consumption process of urban forest park,real estate agent ... The paper had introduced researches on urban forest park and analyzed its particularity.In terms of elimination of externality during development and tourism consumption process of urban forest park,real estate agent had been introduced and two assumptions had been proposed to eliminate externality.As for elimination of externality during development of urban forest park,right to use planning land for urban forest park and surrounding land for real estate development would be sold to estate agent who would develop urban forest park and commodity house;the management of forest urban park would be undertaken by tourism development companies for which estate agent would make compensation.As for elimination of externality during tourism consumption process,it would control with policies and laws,or establish ticket system.As the study hadn't been conducted on policies about urban land and real estate,the feasibility of the first assumption needed to be further studied by environmental economists. 展开更多
关键词 Urban forest PARK externalITY DEVELOPMENT TOURISM
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Efficacy and safety of external application of Traditional Chinese Medicine for the treatment of acute gouty arthritis: a systematic review and Meta-analysis 被引量:17
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作者 Huang Xinxing Zhu Zonghua +5 位作者 Wu Guang-hui Min Peng Fei Peng Zhu Tao Wang Xuezong Xiao Lianbo 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2019年第3期297-306,共10页
OBJECTIVE:To evaluate the clinical efficacy and safety of external application of Traditional Chinese Medicine (EATCM) on acute gouty arthritis (AGA).METHODS:Six electronic data bases were retrieved from their incepti... OBJECTIVE:To evaluate the clinical efficacy and safety of external application of Traditional Chinese Medicine (EATCM) on acute gouty arthritis (AGA).METHODS:Six electronic data bases were retrieved from their inception to march 2017.15 randomized controlled clinical trials (RCTs) were included.The quality of the literatures was assessed according to Cochrane review criteria by using RevMan5.3 software;and related data was counted using Stata14.0 software.RESULTS:There was no significant difference in C-reactiveprotein (CRP) between experimental intervention group and control group [(WMD =1.093,95% C/(-2.514,4.701);P =0.553)].In terms of overall efficacy,the EATCM's treatment group was significantly superior to control group [(OR =3.692;95% CI (2.408,5.661);P <0.001)].The EATCM was better than western medicine treatments or other interventions in reducing the adverse reactions [(OR =0.135;95% CI (0.067,0.274);P < 0.001)].All these funnel plots showed unlikelihood of publishing bias.But due to excessive heterogeneity,the statistical results of serum uric acid and visual analogue scale and CRP between the two groups became uncertain.CONCLUSION:The results indicate that EATCM may have greater overall efficacy with fewer adverse drug reactions,although the evidence is weak owing to the low methodological quality and the small number of the included trials. 展开更多
关键词 Arthritis gouty external application DRUGS Medicine Chinese TRADITIONAL Review META-ANALYSIS
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Insights into sludge granulation during anaerobic treatment of high-strength leachate via a full-scale IC reactor with external circulation system 被引量:13
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作者 Tao Wang Zhenxing Huang +3 位作者 Wenquan Ruan Mingxing Zhao Youlian Shao Hengfeng Miao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第2期227-234,共8页
In this study, a full-scale internal circulation(IC) reactor coupled with an external circulation system was developed to treat high-strength leachate from a municipal solid waste(MSW)incineration plant, in which ... In this study, a full-scale internal circulation(IC) reactor coupled with an external circulation system was developed to treat high-strength leachate from a municipal solid waste(MSW)incineration plant, in which anaerobic sludge granulation was intensively investigated. Results showed that the IC reactor achieved excellent treatment performance under high organic loading rates(OLR) of 21.06–25.16 kg chemical oxygen demand(COD)/(m3? day). The COD removal efficiency and biogas yield respectively reached 89.4%–93.4% and 0.42–0.50 m3/kg COD.The formation of extracellular polymeric substances(EPS) was closely associated with sludge granulation. Protein was the dominant component in sludge EPS, and its content was remarkably increased from 21.6 to 99.7 mg/g Volatile Suspended Solid(VSS) during the reactor operation. The sludge Zeta potential and hydrophobicity positively correlated with the protein/polysaccharide ratio in EPS, and they were respectively increased from-26.2 m V and 30.35% to-10.6 m V and 78.67%, which was beneficial to microbial aggregation. Three-dimensional fluorescence spectroscopy(3 D-EEM) and Fourier transform infrared spectroscopy(FT-IR)analysis further indicated the importance of protein-like EPS substances in the sludge granulation. Moreover, it was also found that the secondary structures of EPS proteins varied during the reactor operation. 展开更多
关键词 Internal circulation reactor LEACHATE Sludge granulation Extracellular polymeric substances external circulation
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PD-type iterative learning control for nonlinear time-delay system with external disturbance 被引量:12
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作者 Zhang Baolin Tang Gongyou Zheng Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期600-605,共6页
The PD-type iterative learning control design of a class of affine nonlinear time-delay systems with external disturbances is considered. Sufficient conditions guaranteeing the convergence of the n-norm of the trackin... The PD-type iterative learning control design of a class of affine nonlinear time-delay systems with external disturbances is considered. Sufficient conditions guaranteeing the convergence of the n-norm of the tracking error are derived. It is shown that the system outputs can be guaranteed to converge to desired trajectories in the absence of external disturbances and output measurement noises. And in the presence of state disturbances and measurement noises, the tracking error will be bounded uniformly. A numerical simulation example is presented to validate the effectiveness of the proposed scheme. 展开更多
关键词 time-delay system nonlinear system iterative learning control CONVERGENCE external disturbance.
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Nonlinear Dynamic Analysis of Coupled Gear-Rotor-Bearing System with the Effect of Internal and External Excitations 被引量:13
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作者 ZHOU Shihua SONG Guiqiu +1 位作者 REN Zhaohui WEN Bangchun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第2期281-292,共12页
Extensive studies on nonlinear dynamics of gear systems with internal excitation or external excitation respectively have been carried out.However,the nonlinear characteristics of gear systems under combined internal ... Extensive studies on nonlinear dynamics of gear systems with internal excitation or external excitation respectively have been carried out.However,the nonlinear characteristics of gear systems under combined internal and external excitations are scarcely investigated.An eight-degree-of-freedom(8-DOF)nonlinear spur gear-rotor-bearing model,which contains backlash,transmission error,eccentricity,gravity and input/output torque,is established,and the coupled lateral-torsional vibration characteristics are studied.Based on the equations of motion,the coupled spur gear-rotor-bearing system(SGRBS)is investigated using the Runge-Kutta numerical method,and the effects of rotational speed,error fluctuation and load fluctuation on the dynamic responses are explored.The results show that a diverse range of nonlinear dynamic characteristics such as periodic motion,quasi-periodic motion,chaotic behaviors and impacts exhibited in the system are strongly attributed to the interaction between internal and external excitations.Significantly,the changing rotational speed could effectively control the vibration of the system.Vibration level increases with the increasing error fluctuation.Whereas the load fluctuation has an influence on the nonlinear dynamic characteristics and the increasing excitation force amplitude makes the vibration amplitude increase,the chaotic motion may be restricted.The proposed model and numerical results can be used for diagnosis of faults and vibration control of practical SGRBS. 展开更多
关键词 spur gear-rotor-bearing system(SGRBS) BACKLASH ECCENTRICITY internal and external excitations coupled lateral·torsional vibration
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Weatherability Studies on External Insulation Thermal System of Expanded Polystyrene Board,Polystyrene Granule and Polyurethane Foam 被引量:5
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作者 尹秀琴 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第6期1027-1032,共6页
Atmospheric exposure tests including two experimental stages of high temperature-spraying water cycle and heating-refrigeration cycle were carried out on three currently used ETIS of expanded polystyrene(EPS) board,... Atmospheric exposure tests including two experimental stages of high temperature-spraying water cycle and heating-refrigeration cycle were carried out on three currently used ETIS of expanded polystyrene(EPS) board,polystyrene granule mortar and polyurethane foam in order to study the weatherablility of external thermal insulation system(ETIS).The change rules of adhesive strength were hereby studied at different time period of atmospheric exposure tests.The experimental results show that the adhesive strength of three kinds of ETIS changes a little during high temperature-spraying water cycle,but the adhesive strength of ETIS with EPS board decreases significantly after heating-refrigeration cycle.The lowering rate of adhesive strength with painting finishes is obviously faster than that of tile finishes for ETIS of EPS board during heating-refrigeration cycle.The weatherability of ETIS with EPS board is worse than the other two,and ETIS of polystyrene granule mortar and polyurethane foam are more suitable than ETIS of EPS board in cold area. 展开更多
关键词 external thermal insulation system EPS board polystyrene granule atmospheric exposure tests adhesive strength
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Factors influencing utilization and satisfaction with external breast prosthesis in patients with mastectomy:A systematic review 被引量:6
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作者 Ya-nan Liang Bo Xu 《International Journal of Nursing Sciences》 2015年第2期218-224,共7页
Purpose:The aim of this study is to describe and analyse the factors which influence utilization of EBPs among breast cancer patients worldwide and particularly in China.Methods:Literature searches were conducted in W... Purpose:The aim of this study is to describe and analyse the factors which influence utilization of EBPs among breast cancer patients worldwide and particularly in China.Methods:Literature searches were conducted in Wanfang,CNKI,and PubMed databses in order to identify relevant articles published in both Chinese and English up to October 2014.The phrase“external breast prosthesis”in Chinese was used to search titles,abstracts,and key words to find articles in Wanfang and CNKI electronic databases.Synonyms and related terms for external breast prosthesis were combined and used for searches performed in PubMed.Additional references were subsequently extracted from the bibliographies of all included articles and reviews.Qualitative analysis was applied in this study rather than meta-analysis.Results:The number of relevant studies published in other countries is five times greater than the literature published in China,with most articles written by Australian scientists.Based on the existing references,reconstruction,comfort,appearance,cost,mental status,and supportive information were the main factors influencing choice of treatment options by patients.Conclusion:Six main factors influencing EBP use worldwide were identified.Although the number of breast cancer cases per year is increasing at a much higher rate in China relative to the average number globally,relevant studies on Chinese patients are lacking.Thus,further studies should be undertaken in China in order to develop effective service modalities in order to improve quality of life of patients. 展开更多
关键词 external prosthesis UTILIZATION SATISFACTION systematic review
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Nonextensive and extensive thermostatistic properties of Fermi systems trapped in different external potentials 被引量:3
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作者 黄志福 欧聪杰 陈金灿 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1380-1388,共9页
The thermostatistic properties of a q-generalized Fermi system trapped in a generic power-law potential are studied, based on the generalized statistic distribution derived from the Tsallis entropy. The total number o... The thermostatistic properties of a q-generalized Fermi system trapped in a generic power-law potential are studied, based on the generalized statistic distribution derived from the Tsallis entropy. The total number of particles, the total energy, and the heat capacity at constant volume of the system are derived. The thermostatistic characteristics of the system are discussed in detail. It is found that the thermostatistic properties of such a system depend closely on parameter q, dimensional number of the space, kinetic characteristics of particles and shapes of the external potential, and the external potential has a great influence on the thermostatistie properties of the system. Moreover, it is shown that the results obtained here are very general and can be used to unify the description of the nonextensive and extensive thermostatistie properties of a class of Fermi systems trapped in different external potentials so that the important conclusions of many typical Fermi systems in the literature may be directly derived from the present paper. 展开更多
关键词 generalized Fermi system external potential thermostatistic property
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Design and Combustion Characteristic Analysis of Free Piston Stirling Engine External Combustion System 被引量:4
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作者 JIN Xudong LV Tian +2 位作者 YU Guoyao LIU Jiawei HUANG Xiaoyu 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第S1期50-55,共6页
The free piston Stirling engine external combustion system was simulated to investigate the diesel-air combustion characteristics in order to demonstrate its feasibility by computational fluid dynamics(CFD). The diffe... The free piston Stirling engine external combustion system was simulated to investigate the diesel-air combustion characteristics in order to demonstrate its feasibility by computational fluid dynamics(CFD). The different effects on combustion were distinguished by analyzing the combustion burner, the injection position of diesel oil, the front tube arrangement of Stirling heater head and the back fin. The results show that the tilted front tube arrangement of the heater head with the back fin is the best practicable technology while the distance between the diesel nozzle position and the swirler top is 0. Its total heat flux is 15.6 kW, and the average heat transfer coefficients of the front and back tubes are 127 W/(m2· K) and 192 W/(m2· K), respectively. The heat transfer is mainly through convection, and the proportion of radiative heat transfer is only 16.9%. The best combustion efficiency of the free piston Stirling engine external combustion system is 86%. 展开更多
关键词 Stirling engine external combustion system numerical simulation diesel-air combustion
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External stability of fractional-order control systems 被引量:2
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作者 曾庆山 曹广益 朱新坚 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第1期32-36,共5页
The external stability of fractional-order continuous linear control systems described by both fractional-order state space representation and fractional-order transfer function is mainly investigated in this paper. I... The external stability of fractional-order continuous linear control systems described by both fractional-order state space representation and fractional-order transfer function is mainly investigated in this paper. In terms of Lyapunov’s stability theory and the stability analysis of the integer-order linear control systems, the definitions of external stability for fractional-order control systems are presented. By using the theorems of the Mittag-Leffler function in two parameters, the necessary and sufficient conditions of external stability are directly derived. The illustrative examples and simulation results are also given. 展开更多
关键词 fractional calculus fractional-order system fractional-order state space representation fractional-order transfer function external stability
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Role of coatings and materials of external fixation pins on the rates of pin tract infection:A systematic review and meta-analysis 被引量:2
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作者 Cristhopher Stoffel Bruno Eltz Mauro Jose Salles 《World Journal of Orthopedics》 2021年第11期920-930,共11页
BACKGROUND Infection at the pin tract is a frequent and feared complication of external fixators(EF).The type of pin material and coatings have been regarded as possibly influencing infection rates.Over the last 20 ye... BACKGROUND Infection at the pin tract is a frequent and feared complication of external fixators(EF).The type of pin material and coatings have been regarded as possibly influencing infection rates.Over the last 20 years,few prospective clinical studies and systematic reviews addressed the role of coated pins on the rate of pin site infection in human clinical studies.AIM To assess the EF literature over the past 20 years on the clinical benefits of pins manufactured from varied materials and coating systems and their possible role in pin tract infection rates.METHODS We performed a systematic review according to the PRISMA and PICOS guidelines using four scientific platforms:PubMed,LiLacs,SciELO,and Cochrane.We searched the literature for related publications over the past 20 years.RESULTS A literature search yielded 29 articles,among which seven met the inclusion criteria.These studies compared stainless-steel pins and pins coated with hydroxyapatite(HA),titanium and silver.The pin tract infection definitions were arbitrary and not standardized among studies.Most studies included a low number of patients in the analysis and used a short follow-up time.Three metaanalyses were carried out,comparing stainless steel vs silver pins,stainless steel vs HA-coated pins,and titanium vs HA-coated pins.None of this analysis resulted in statistically significant differences in pin tract infection rates.CONCLUSION Currently,no clinical evidence supports the advantage of EF pins manufactured with materials other than stainless steel or coated over uncoated pins in reducing the rates of pin tract infections.A standardized definition of pin tract infection in external fixation is still lacking. 展开更多
关键词 external fixator Pin tract infection Stainless steel pin Coated pin Coating systems Pin site infection
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External Costs and Optimum Use of Nitrogen Fertilizer Based on the Balance of Economic and Ecological Benefits in the Paddy Field System of the Dongting Lake Area, China 被引量:1
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作者 XIANG Ping-an ZHOU Yan +3 位作者 JIANG Ju-ao ZHENG Hua YAN Hui-min HUANG Huang 《Agricultural Sciences in China》 CAS CSCD 2007年第3期347-354,共8页
The external costs and the optimum use of nitrogen fertilizer based on the balance of economic and ecological benefits was studied with the paddy field system of Dongting Lake area, one of the main food production reg... The external costs and the optimum use of nitrogen fertilizer based on the balance of economic and ecological benefits was studied with the paddy field system of Dongting Lake area, one of the main food production regions in China. The environmental impact was economically evaluated using methods of the environmental impact economical evaluation. The optimum use of nitrogen fertilizer was calculated based on the exterior diseconomy theory and by using the production function model. Both ecological benefits and farmers' economic benefits were considered. It was calculated on the data from 2002 that the losses caused by inappropriate utilization of nitrogen fertilizer in the process of food production were fishery, 0.1 × 10^7 RMB yuan; water treatment, 1.02 × 10^8 RMB yuan; tour business, 0.11 ×10^8 RMB yuan, and habitation environment, 0.3 × 10^7 RMB yuan, totally equivalent to 0.41 RMB yuan kg^-1 N. The economically satisfactory and the ecological agronomic nitrogen fertilizer dose for current production was 138 and 137 kg ha^-1, respectively. The research showed that the actual nitrogen fertilizer application amount in the paddy field system of the Dongting Lake area already reached or exceeded the farmers' economic satisfaction and the ecological agronomic nitrogen fertilizer dose for current production. An environmental tax is suggested to impose on over-use of nitrogen fertilizer. 展开更多
关键词 nitrogen fertilizer external costs economic benefit ecological benefit Dongting Lake area
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EXACT SOLUTIONS FOR STATIONARY RESPONSES OF SEVERAL CLASSES OF NONLINEAR SYSTEMS TO PARAMETRIC AND/OR EXTERNAL WHITE NOISE EXCITATIONS 被引量:2
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作者 朱位秋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第2期165-175,共11页
The exact solutions for stationary responses of one class of the second order and three classes of higher order nonlinear systems to parametric and/or external while noise excitations are constructed by using Fokkcr-P... The exact solutions for stationary responses of one class of the second order and three classes of higher order nonlinear systems to parametric and/or external while noise excitations are constructed by using Fokkcr-Planck-Kolmogorov et/ualion approach. The conditions for the existence and uniqueness and the behavior of the solutions are discussed. All the systems under consideration are characterized by the dependence ofnonconservative fqrces on the first integrals of the corresponding conservative systems and arc catted generalized-energy-dependent f G.E.D.) systems. It is shown taht for each of the four classes of G.E.D. nonlinear stochastic systems there is a family of non-G.E.D. systems which are equivalent to the G.E.D. system in the sense of having identical stationary solution. The way to find the equivalent stochastic systems for a given G.E.D. system is indicated and. as an example, the equivalent stochastic systems for the second order G.E. D. nonlinear stochastic system are given. It is pointed out and illustrated with example that the exact stationary solutions for many non-G.E.D. nonlinear stochastic systems may he found by searching the equivalent G.E.D. systems. 展开更多
关键词 EXACT SOLUTIONS FOR STATIONARY RESPONSES OF SEVERAL CLASSES OF NONLINEAR systemS TO PARAMETRIC AND/OR external WHITE NOISE EXCITATIONS
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Statistical mechanics of a nonequilibrium steady-state classical particle system driven by a constant external force
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作者 Jie Yao Yanting Wang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第11期104-108,共5页
A classical particle system coupled with a thermostat driven by an external constant force reaches its steady state when the ensemble-averaged drift velocity does not vary with time.In this work,the statistical mechan... A classical particle system coupled with a thermostat driven by an external constant force reaches its steady state when the ensemble-averaged drift velocity does not vary with time.In this work,the statistical mechanics of such a system is derived solely based on the equiprobability and ergodicity principles,free from any conclusions drawn on equilibrium statistical mechanics or local equilibrium hypothesis.The momentum space distribution is determined by a random walk argument,and the position space distribution is determined by employing the equiprobability and ergodicity principles.The expressions for energy,entropy,free energy,and pressures are then deduced,and the relation among external force,drift velocity,and temperature is also established.Moreover,the relaxation towards its equilibrium is found to be an exponentially decaying process obeying the minimum entropy production theorem. 展开更多
关键词 nonequilibrium steady state constant external force DISSIPATION statistical mechanics
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