Although train modeling research is vast, most available simulation tools are confined to city-or trip-scale analysis, primarily offering micro-level simulations of network segments. This paper addresses this void by ...Although train modeling research is vast, most available simulation tools are confined to city-or trip-scale analysis, primarily offering micro-level simulations of network segments. This paper addresses this void by developing the Ne Train Sim simulator for heavy long-haul freight trains on a network of multiple intersecting tracks. The main objective of this simulator is to enable a comprehensive analysis of energy consumption and the associated carbon footprint for the entire train system. Four case studies were conducted to demonstrate the simulator's performance. The first case study validates the model by comparing Ne Train Sim output to empirical trajectory data. The results demonstrate that the simulated trajectory is precise enough to estimate the train energy consumption and carbon dioxide emissions. The second application demonstrates the train-following model considering six trains following each other. The results showcase the model ability to maintain safefollowing distances between successive trains. The next study highlights the simulator's ability to resolve train conflicts for different scenarios. Finally, the suitability of the Ne Train Sim for modeling realistic railroad networks is verified through the modeling of the entire US network and comparing alternative powertrains on the fleet energy consumption.展开更多
Objective: The clinical clerkship and practice stage plays a pivotal role in the transition of medical students from theoretical knowledge to practical application, bridging the gap between classroom learning and real...Objective: The clinical clerkship and practice stage plays a pivotal role in the transition of medical students from theoretical knowledge to practical application, bridging the gap between classroom learning and real-life clinical experience. In order to improve the teaching quality of interns and probationers, we try to let them practice the skills of laparoscopic surgery in the early stage, and summed up a set of evaluation methods that can be widely used in medical education. Methods: From September 2019 to December 2019, a total of 54 interns and 72 trainees were selected as research objects. They were assigned to training sessions and their proficiency was assessed before and after the training. The change in proficiency is compared to determine whether the training course is valuable. Results: Before the operation training, the interns scores were BP 17.3 3.1, CC 17.9 3.4, KT 16.4 3.4, LS 16.7 3.3. The results of probationers were BP 16.9 2.7, CC 16.8 2.8, KT 15.2 1.6, and LS 14.8 2.2. After completing the operations training, the results of interns were BP 21.1 1.9, CC 20.6 2.7, KT 19.6 3.0, and LS 20.9 1.4. The probationers scores were BP 19.3 3.2, CC 19.6 3.5, KT 19.6 2.6, and LS 20.0 2.4. After the operation training, the performance of the intern group was better than that before the training (P < 0.05). The same is true of the probationer group. The time-consuming intern examinations were BP 147.9 38.5 s, CC 123.2 28.7 s, KT 82.6 24.1 s and LS 162.5 31.1 s. The examination time of probationers were BP 179.9 46.4 s, CC 132.1 24.3 s, KT 109.3 27.5 s and LS 210.0 58.8 s. Conclusion: Simulation training for laparoscopic surgery can improve minimally invasive surgical techniques for interns and probationers.展开更多
Whole trip longitudinal dynamics and energy analysis of heavy haul trains are required by operators and manufacturers to enable optimisation of train controls and rolling stock components. A new technology named train...Whole trip longitudinal dynamics and energy analysis of heavy haul trains are required by operators and manufacturers to enable optimisation of train controls and rolling stock components. A new technology named train dynamics and energy analyser/train simulator (TDEAS) has been developed by the State Key Laboratory of Traction Power in China to perform detailed whole trip longitudinal train dynamics and energy analyses. Facilitated by a controller user interface and a graphic user interface, the TDEAS can also be used as a train driving simulator. This paper elaborates the modelling of three primary parts in the TDEAS, namely wagon connection systems, air brake systems and train energy components. TDEAS uses advanced wedge-spring draft gear models that can simulate a wider spectrum of friction draft gear behaviour. An effective and efficient air brake model that can simulate air brake systems in various train configurations has been integrated. In addition, TDEAS simulates the train energy on the basis of a detailed longitudinal train dynamics simulation, which enables a further perspective of the train energy composition and the overall energy consumption. To demonstrate the validity of the TDEAS, a case study was carried out on a 120-km-long Chinese railway. The results show that the employment of electric locomotives with regenerative braking could bring considerable energy benefits. Nearly 40 % of the locomotive energy usage could be collected from the dynamic brake system. Most of tractive energy was dissipated by propulsion resistance that accounted for 42.48 % of the total energy. Only a small amount of tractive energy was dissipated by curving resistance, air brake and draft gear systems.展开更多
Objective:A computer-based STS(simulative training system) in providing pre-hospital trauma care at a disaster site was applied to teaching nursing students in the Second Military Medical University,China.This article...Objective:A computer-based STS(simulative training system) in providing pre-hospital trauma care at a disaster site was applied to teaching nursing students in the Second Military Medical University,China.This article reports on the teaching effectiveness of this system.Methods:Among 92 participants,46 were in the study group and 46 were in the 'control' group. Each student completed a multiple-choice quiz after completing 18 hours(six three-hour sessions) of the study module,and a score was recorded.The simulative training module was completed only by the study group;the 'control' group was assigned in-class discussions for the same amount of time covering the same content as the study group.The final course scores,which included both comprehensive and group task-based tests were compared between these two groups.The study used a descriptive and comparative approach for quantitative data analysis.Tests of independency between the multiple choice scores and the simulation scores were also performed.Finally,anonymous surveys were conducted.Results:The study group performed better than the 'control' group with a significantly higher average score for the group scenario task-based test score,and consequently the study group's final course score was significantly higher than the 'control' group.As per chi-square tests,no significant associations were found between the multiple choice scores and the simulated training scores.The final surveys showed students overwhelmingly agreed that STS training improved their knowledge and skills,their ability to recognize a potential critical event, and their initial response for trauma care at pre-hospital settings.The survey responses of the study group were noteworthy as they indicated that students recognized the importance of simulative training,appreciated the realism of the simulation,and were able to fight/adjust to the stressful feelings in order to focus on the task.Conclusion:Computer-based STS may be an effective teaching model to help students improve their capability in providing pre-hospital trauma care,and in their effectiveness in disaster response.展开更多
Dynamic responses of a carriage under excitation with the German high-speed low-interference track spectrum together with the air pressure pulse generated as high-speed trains passing each other are investigated with ...Dynamic responses of a carriage under excitation with the German high-speed low-interference track spectrum together with the air pressure pulse generated as high-speed trains passing each other are investigated with a multi-body dynamics method.The variations of degrees of freedom(DOFs:horizontal movement,roll angle,and yaw angle),the lateral wheel-rail force,the derailment coefficient and the rate of wheel load reduction with time when two carriages meet in open air are obtained and compared with the results of a single train travelling at specifie speeds.Results show that the rate of wheel load reduction increases with the increase of train speed and meets some safety standard at a certain speed,but exceeding the value of the rate of wheel load reduction does not necessarily mean derailment.The evaluation standard of the rate of wheel load reduction is somewhat conservative and may be loosened.The pressure pulse has significan effects on the train DOFs,and the evaluations of these safety indexes are strongly suggested in practice.The pressure pulse has a limited effect on the derailment coefficien and the lateral wheel-rail force,and,thus,their further evaluations may be not necessary.展开更多
Analysis of the aerodynamic performance of high-speed trains in special cuts would provide references for the critical overturning velocity and complement the operation safety management under strong winds.This work w...Analysis of the aerodynamic performance of high-speed trains in special cuts would provide references for the critical overturning velocity and complement the operation safety management under strong winds.This work was conducted to investigate the flow structure around trains under different cut depths,slope angles using computational fluid dynamics(CFD).The high-speed train was considered with bogies and inter-carriage gaps.And the accuracy of the numerical method was validated by combining with the experimental data of wind tunnel tests.Then,the variations of aerodynamic forces and surface pressure distribution of the train were mainly analyzed.The results show that the surroundings of cuts along the railway line have a great effect on the crosswind stability of trains.With the slope angle and depth of the cut increasing,the coefficients of aerodynamic forces tend to reduce.An angle of 75°is chosen as the optimum one for the follow-up research.Under different depth conditions,the reasonable cut depth for high-speed trains to run safely is 3 m lower than that of the conventional cut whose slope ratio is 1:1.5.Furthermore,the windward slope angle is more important than the leeward one for the train aerodynamic performance.Due to the shield of appropriate cuts,the train body is in a minor positive pressure environment.Thus,designing a suitable cut can contribute to improving the operation safety of high-speed trains.展开更多
Simulation-based mastery learning(SBML)is an emerging form of competencybased training that has been proposed as the next standard method for procedural task training,including that in gastr-ointestinal endoscopy.Curr...Simulation-based mastery learning(SBML)is an emerging form of competencybased training that has been proposed as the next standard method for procedural task training,including that in gastr-ointestinal endoscopy.Current basic gastrointestinal endoscopy training relies on the number of procedures performed,and it has been criticized for its lack of objective standards that result in variable skills among trainees and its association with patient safety risk.Thus,incorporating simulators into a competency-based curriculum seems ideal for gastrointestinal endoscopy training.The curriculum for SBML in gastrointestinal endoscopy is currently being developed and has promising potential to translate into the clinical performance.Unlike the present apprenticeship model of“see one,do one,teach one,”SBML integrates a competency-based curriculum with specific learning objectives alongside simulation-based training.This allows trainees to practice essential skills repeatedly,receive feedback from experts,and gradually develop their abilities to achieve mastery.Moreover,trainees and trainers need to understand the learning targets of the program so that trainees can focus their learning on the necessary skills and trainers can provide structured feedback based on the expected outcomes.In addition to learning targets,an assessment plan is essential to provide trainees with future directions for their improvement and ensure patient safety by issuing a passing standard.Finally,the SBML program should be planned and managed by a specific team and conducted within a developed and tested curriculum.This review discusses the current state of gastr-ointestinal endoscopy training and the role of SBML in that field.展开更多
To utilize exist SCADA(Supervisory Control and Data Acqui si tion)/EMS (Energy Management System) fully and economize capital, Henan Electric Power Dispatching and Communication Center in China established a set of H...To utilize exist SCADA(Supervisory Control and Data Acqui si tion)/EMS (Energy Management System) fully and economize capital, Henan Electric Power Dispatching and Communication Center in China established a set of Henan Dispatcher Training Simulator (HNDTS) base on its exist SCADA/EMS. In order to i ntegrated with exist SCADA/EMS, the integration method and technique are propose d. Graph data integration discussed with emphasis. After integration implemented , HNDTS can share all data with SCADA/EMS and dispatchers can be trained in same environment as real work situation, in the same time it can avoid amout of work of maintenance engineers. Both advantages and disadvantages of integration are analyzed. In the end of paper, the requirement for future DTS is put forward bas e on the experience of author.展开更多
Simulating large-scale and complex systems is commonly considered a difficult and time-consuming task. In this paper, we propose a partial simulation way to speed up the simulation with real time demands. It is based ...Simulating large-scale and complex systems is commonly considered a difficult and time-consuming task. In this paper, we propose a partial simulation way to speed up the simulation with real time demands. It is based on the idea that a train traffic diagram is expressed in a network, and through calculating the maximal long path in the network the simulation is done, but only within a particular partial area.Upon this, we let it become a problem oriented simulation. The simulation could be started at any time,from any trains or at any stations and stopped as the same way according to the problem to be concerned.We can use this kind of simulation to analyse or confirm the correctness of traffic schedule at a high speed to meet the real time demands.展开更多
The simulator is a combination of computational functions describing physical system, distributed rule and knowledge bases, and a reasoning machine, all executing in parallel. The hardware,comprising two levels of mul...The simulator is a combination of computational functions describing physical system, distributed rule and knowledge bases, and a reasoning machine, all executing in parallel. The hardware,comprising two levels of multiprocessor network-- a T800 transputer and STD--BUS computer systems--and analogue and I/O boards, has been used successfully to train and simulate a 100 MW power system at a low cost. The system has wide applications in industry.展开更多
A multi-objective improved genetic algorithm is constructed to solve the train operation simulation model of urban rail train and find the optimal operation curve.In the train control system,the conversion point of op...A multi-objective improved genetic algorithm is constructed to solve the train operation simulation model of urban rail train and find the optimal operation curve.In the train control system,the conversion point of operating mode is the basic of gene encoding and the chromosome composed of multiple genes represents a control scheme,and the initial population can be formed by the way.The fitness function can be designed by the design requirements of the train control stop error,time error and energy consumption.the effectiveness of new individual can be ensured by checking the validity of the original individual when its in the process of selection,crossover and mutation,and the optimal algorithm will be joined all the operators to make the new group not eliminate on the best individual of the last generation.The simulation result shows that the proposed genetic algorithm comparing with the optimized multi-particle simulation model can reduce more than 10%energy consumption,it can provide a large amount of sub-optimal solution and has obvious optimization effect.展开更多
Objective To assess the face and construct validity of a full procedural transurethral prostate resection simulator ( TURPSimTM ) in training of transurethral resection of prostate. Methods Ten experienced and thirtee...Objective To assess the face and construct validity of a full procedural transurethral prostate resection simulator ( TURPSimTM ) in training of transurethral resection of prostate. Methods Ten experienced and thirteen inexperienced urologists ( TURP experience ≥ 30 and展开更多
Aim Toshorten integral design period of electric vehicles Methods The electric vehicle simulation program(EVSP), a modular user-friendly program which is written in Borland C++ OWL for Windows was developed. Results ...Aim Toshorten integral design period of electric vehicles Methods The electric vehicle simulation program(EVSP), a modular user-friendly program which is written in Borland C++ OWL for Windows was developed. Results EVSP allows simulating the dynamic and the economy performance of electric vehicles.EVSP provides many kinds of data input module,a large components library of electric vehicles and several kinds of speed cycle with these library,it is easily to develop a new concept of different drive trains or even to compare or improve the existing electric vehicles. The paper simulated the performance of YW6120DD Electric Bus, and analyzed the test results comparing with simulation results Conclusion The simulation results indicate that the EVSP may contribute to the developments of electric vehicles in general and the definition of the optimal match management in the drive train in particular.展开更多
BACKGROUND:There are several reasons why resuscitation measures may lead to inferior results:difficulties in team building,delayed realization of the emergency and interruption of chest compression.This study investig...BACKGROUND:There are several reasons why resuscitation measures may lead to inferior results:difficulties in team building,delayed realization of the emergency and interruption of chest compression.This study investigated the outcome of a new form of in-hospital cardiopulmonary resuscitation(CPR) training with special focus on changes in self-assurance of potential helpers when faced with emergency situations.METHODS:Following a 12-month period of CPR training,questionnaires were distributed to participants and non-participants.Those non-participants who intended to undergo the training at a later date served as control group.RESULTS:The study showed that participants experienced a significant improvement in selfassurance,compared with their remembered self-assurance before the training.Their self-assurance also was significantly greater than that of the control group of non-participants.CONCLUSION:Short lessons in CPR have an impact on the self-assurance of medical and non-medical personnel.展开更多
Point-of-care ultrasound(POCUS)is a powerful diagnostic tool and provides treatment guidelines in acute critical settings.However,the limitation of using POCUS is operator dependent.Appropriate and validated training ...Point-of-care ultrasound(POCUS)is a powerful diagnostic tool and provides treatment guidelines in acute critical settings.However,the limitation of using POCUS is operator dependent.Appropriate and validated training for acquiring and using skills in practice must be conducted before using POCUS in clinical settings in order to keep patients safe.Simulation education models have been introduced as a way to solve and overcome these concerns.However,the commercial simulator with sufficiently secured fidelity is expensive and not always available.This review focused on the inexpensive and easily made simulators for education on POCUS in critical specific situations related to the airway,breathing,circulation,and disability.We introduced the simulators that used non-infectious materials,with easily transportable features,and that had a sonographic appearance reproducibility similar to human tissue.We also introduced the recipe of each simulator in two parts:Materials surrounding disease simulators(surrounding materials)and specific disease simulators themselves(target simulators).This review article covered the following:endotracheal or oesophageal intubation,lung(A-lines,B-lines,lung sliding,and pleural effusions such as hemothorax),central vein access,pericardial fluid(cardiac tamponade),the structure related to the eyes,soft tissue abscess,nerve(regional nerve block),and skull fracture simulators.展开更多
Diesel fuel combustion results in exhaust containing air pollutants and greenhouse gas emissions.Many railway vehicles use diesel fuel as their energy source.Exhaust emissions,as well as concerns about economical,alte...Diesel fuel combustion results in exhaust containing air pollutants and greenhouse gas emissions.Many railway vehicles use diesel fuel as their energy source.Exhaust emissions,as well as concerns about economical,alternative power supply,have driven efforts to move to hydrogen motive power.Hydrogen fuel cell technology applied to railways offers the opportunity to eliminate harmful exhaust emissions and the potential for a low-or zero-emission energy supply chain.Currently,only multiple-unit trains with hydrail technology operate commercially.Development of an Integrated Hybrid Train Simulator for intercity railway is presented.The proposed tool incorporates the effect of powertrain components during the wheel-to-tank process.Compared to its predecessors,the proposed reconfigurable tool provides high fidelity with medium requirements and minimum computation time.Single train simulation and the federal government’s Greenhouse gases,Regulated Emissions,and Energy use in Transportation(GREET)model are used in combination to evaluate the feasibility of various train and powertrain configurations.The Piedmont intercity service operating in North Carolina is used as a case study.The study includes six train configurations and powertrain options as well as nine hydrogen supply options in addition to the diesel supply.The results show that a hydrail option is not only feasible,but a low-or zero-carbon hydrogen supply chain could be possible.展开更多
In modem four-stroke engine technology, variable valve timing and lift control offers potential benefits for making a high-performance engine. A novel electro-hydraulic fully variable valve train for four-stroke autom...In modem four-stroke engine technology, variable valve timing and lift control offers potential benefits for making a high-performance engine. A novel electro-hydraulic fully variable valve train for four-stroke automotive engines is introduced. The construction of the nonlinear mathematic model of the valve train system and its dynamic analysis are also presented. Experimental and simulation results show that the novel electro-hydraulic valve train can achieve fully variable valve timing and lift control. Consequently the engine performance on different loads and speeds will be significantly increased. The technology also permits the elimination of the traditional throttle valve in the gasoline engines and increases engine design flexibility.展开更多
In this paper, a new simulation approach for solving the mixed train scheduling problem on the high-speed double-track rail line is presented. Based on the discrete-time movement model, we propose control strategies f...In this paper, a new simulation approach for solving the mixed train scheduling problem on the high-speed double-track rail line is presented. Based on the discrete-time movement model, we propose control strategies for mixed train movement with different speeds on a high-speed double-track rail line, including braking strategy, priority rule, travelling strategy, and departing rule. A new detailed algorithm is also presented based on the proposed control strategies for mixed train movement. Moreover, we analyze the dynamic properties of rail traffic flow on a high-speed rail line. Using our proposed method, we can effectively simulate the mixed train schedule on a rail line. The numerical results demonstrate that an appropriate decrease of the departure interval can enhance the capacity, and a suitable increase of the distance between two adjacent stations can enhance the average speed. Meanwhile, the capacity and the average speed will be increased by appropriately enhancing the ratio of faster train number to slower train number from 1.展开更多
Objectives:lnterprofessional collaboration in the training of nursing and psychology students helps provide students of both disciplines with the ability and competences they need to best attend to their patients.This...Objectives:lnterprofessional collaboration in the training of nursing and psychology students helps provide students of both disciplines with the ability and competences they need to best attend to their patients.This study implemented and analyzed a method for developing the competences of each discipline in a scenario of joint clinical simulation that incorporates mental and physical health simultaneously,and measured the caring ability of the participating students.Methods:Participants took a self-applied survey measuring their own caring ability.After,a clinical simulation was performed where nursing students performed clinical interviews on psychology students,who acted as standardized patients.Caring abilities were measured in the nursing students,and the psychology students implemented an intervention service measuring caring ability and brief-debrief simulation by coaching to nursing students.Results:The results indicated that the self-applied questionnaire of caring ability resulted in scores significantly higher than what was measured by observers.Conclusions:The results contribute to the development of protocols,training and collaborative work practices in interprofessional education,which allow the scaling of these competences.展开更多
Objective:To summarize and produce aggregated evidence on the effect of simulation-based teaching on skill performance in the nursing profession.Simulation is an active learning strategy involving the use of various r...Objective:To summarize and produce aggregated evidence on the effect of simulation-based teaching on skill performance in the nursing profession.Simulation is an active learning strategy involving the use of various resources to assimilate the real situation.It enables learners to improve their skills and knowledge in a coordinated environment.Methods:Systematic literature search of original research ar ticles was carried out through Google Scholar,Medline,and Cochrane Cumulative Index to Nursing and Allied Health Literature(CINAHL)databases.Studies conducted on simulation-based teaching and skill performance among nursing students or clinical nursing staff from 2010 to 2019,and published in the English language,were included in this study.Methodological quality was assessed by Joanna Briggs Institute,and the risk of bias was also assessed by Cochrane risk of bias and the risk of bias assessment tool for non-randomized studies(ROBINS-I)checklists.Results:Initially,638 titles were obtained from 3 sources,and 24 original studies with 2209 study par ticipants were taken for the final analysis.Of the total studies,14(58.3%)used single group prep post design,7(29.1%)used high fidelity simulator(HFS),and 7(29.1%)used a virtual simulator(VS).Twenty(83.3%)studies reported improved skill performance following simulation-based teaching.Simulation-based teaching improves skill performance among types of groups(single or double),study regions,high fidelity(HF),low fidelity(LF),and standard patient(SP)users.But the effect over virtual and medium fidelity simulators was not statistically significant.Overall,simulation-based teaching improves the skill performance score among the experimental group(d=1.01,95%confidence interval[CI][0.69–1.33],Z=6.18,P<0.01,93.9%).Significant heterogeneity and publication bias were observed during the pooled analysis.Conclusions:Simulation did improve skill performance among the intervention groups,but the conclusion is uncer tain due to the significant heterogeneity.The large extent of difference among original research has necessitated the development of well-defined assessment methods for skills and standardized simulation set-up for proper assessment of their effects.展开更多
基金funded in part by the Advanced Research Projects AgencyEnergy (ARPA-E), U.S. Department of Energy, under award number DE-AR0001471。
文摘Although train modeling research is vast, most available simulation tools are confined to city-or trip-scale analysis, primarily offering micro-level simulations of network segments. This paper addresses this void by developing the Ne Train Sim simulator for heavy long-haul freight trains on a network of multiple intersecting tracks. The main objective of this simulator is to enable a comprehensive analysis of energy consumption and the associated carbon footprint for the entire train system. Four case studies were conducted to demonstrate the simulator's performance. The first case study validates the model by comparing Ne Train Sim output to empirical trajectory data. The results demonstrate that the simulated trajectory is precise enough to estimate the train energy consumption and carbon dioxide emissions. The second application demonstrates the train-following model considering six trains following each other. The results showcase the model ability to maintain safefollowing distances between successive trains. The next study highlights the simulator's ability to resolve train conflicts for different scenarios. Finally, the suitability of the Ne Train Sim for modeling realistic railroad networks is verified through the modeling of the entire US network and comparing alternative powertrains on the fleet energy consumption.
文摘Objective: The clinical clerkship and practice stage plays a pivotal role in the transition of medical students from theoretical knowledge to practical application, bridging the gap between classroom learning and real-life clinical experience. In order to improve the teaching quality of interns and probationers, we try to let them practice the skills of laparoscopic surgery in the early stage, and summed up a set of evaluation methods that can be widely used in medical education. Methods: From September 2019 to December 2019, a total of 54 interns and 72 trainees were selected as research objects. They were assigned to training sessions and their proficiency was assessed before and after the training. The change in proficiency is compared to determine whether the training course is valuable. Results: Before the operation training, the interns scores were BP 17.3 3.1, CC 17.9 3.4, KT 16.4 3.4, LS 16.7 3.3. The results of probationers were BP 16.9 2.7, CC 16.8 2.8, KT 15.2 1.6, and LS 14.8 2.2. After completing the operations training, the results of interns were BP 21.1 1.9, CC 20.6 2.7, KT 19.6 3.0, and LS 20.9 1.4. The probationers scores were BP 19.3 3.2, CC 19.6 3.5, KT 19.6 2.6, and LS 20.0 2.4. After the operation training, the performance of the intern group was better than that before the training (P < 0.05). The same is true of the probationer group. The time-consuming intern examinations were BP 147.9 38.5 s, CC 123.2 28.7 s, KT 82.6 24.1 s and LS 162.5 31.1 s. The examination time of probationers were BP 179.9 46.4 s, CC 132.1 24.3 s, KT 109.3 27.5 s and LS 210.0 58.8 s. Conclusion: Simulation training for laparoscopic surgery can improve minimally invasive surgical techniques for interns and probationers.
文摘Whole trip longitudinal dynamics and energy analysis of heavy haul trains are required by operators and manufacturers to enable optimisation of train controls and rolling stock components. A new technology named train dynamics and energy analyser/train simulator (TDEAS) has been developed by the State Key Laboratory of Traction Power in China to perform detailed whole trip longitudinal train dynamics and energy analyses. Facilitated by a controller user interface and a graphic user interface, the TDEAS can also be used as a train driving simulator. This paper elaborates the modelling of three primary parts in the TDEAS, namely wagon connection systems, air brake systems and train energy components. TDEAS uses advanced wedge-spring draft gear models that can simulate a wider spectrum of friction draft gear behaviour. An effective and efficient air brake model that can simulate air brake systems in various train configurations has been integrated. In addition, TDEAS simulates the train energy on the basis of a detailed longitudinal train dynamics simulation, which enables a further perspective of the train energy composition and the overall energy consumption. To demonstrate the validity of the TDEAS, a case study was carried out on a 120-km-long Chinese railway. The results show that the employment of electric locomotives with regenerative braking could bring considerable energy benefits. Nearly 40 % of the locomotive energy usage could be collected from the dynamic brake system. Most of tractive energy was dissipated by propulsion resistance that accounted for 42.48 % of the total energy. Only a small amount of tractive energy was dissipated by curving resistance, air brake and draft gear systems.
文摘Objective:A computer-based STS(simulative training system) in providing pre-hospital trauma care at a disaster site was applied to teaching nursing students in the Second Military Medical University,China.This article reports on the teaching effectiveness of this system.Methods:Among 92 participants,46 were in the study group and 46 were in the 'control' group. Each student completed a multiple-choice quiz after completing 18 hours(six three-hour sessions) of the study module,and a score was recorded.The simulative training module was completed only by the study group;the 'control' group was assigned in-class discussions for the same amount of time covering the same content as the study group.The final course scores,which included both comprehensive and group task-based tests were compared between these two groups.The study used a descriptive and comparative approach for quantitative data analysis.Tests of independency between the multiple choice scores and the simulation scores were also performed.Finally,anonymous surveys were conducted.Results:The study group performed better than the 'control' group with a significantly higher average score for the group scenario task-based test score,and consequently the study group's final course score was significantly higher than the 'control' group.As per chi-square tests,no significant associations were found between the multiple choice scores and the simulated training scores.The final surveys showed students overwhelmingly agreed that STS training improved their knowledge and skills,their ability to recognize a potential critical event, and their initial response for trauma care at pre-hospital settings.The survey responses of the study group were noteworthy as they indicated that students recognized the importance of simulative training,appreciated the realism of the simulation,and were able to fight/adjust to the stressful feelings in order to focus on the task.Conclusion:Computer-based STS may be an effective teaching model to help students improve their capability in providing pre-hospital trauma care,and in their effectiveness in disaster response.
基金the National Basic Research Program of China (973 program,Grant 2011CB711100)the National Natural Science Foundation of China (Project No.11372307)the Chinese Academy of Sciences (Grant KJCX2-EW-L03)
文摘Dynamic responses of a carriage under excitation with the German high-speed low-interference track spectrum together with the air pressure pulse generated as high-speed trains passing each other are investigated with a multi-body dynamics method.The variations of degrees of freedom(DOFs:horizontal movement,roll angle,and yaw angle),the lateral wheel-rail force,the derailment coefficient and the rate of wheel load reduction with time when two carriages meet in open air are obtained and compared with the results of a single train travelling at specifie speeds.Results show that the rate of wheel load reduction increases with the increase of train speed and meets some safety standard at a certain speed,but exceeding the value of the rate of wheel load reduction does not necessarily mean derailment.The evaluation standard of the rate of wheel load reduction is somewhat conservative and may be loosened.The pressure pulse has significan effects on the train DOFs,and the evaluations of these safety indexes are strongly suggested in practice.The pressure pulse has a limited effect on the derailment coefficien and the lateral wheel-rail force,and,thus,their further evaluations may be not necessary.
基金Projects(51075401,U1334205)supported by the National Natural Science Foundation of ChinaProject supported by the Scholarship Award for Excellent Innovative Doctoral Student granted by Central South University of ChinaProject(132014)supported by the Fok Ying Tong Education Foundation,China
文摘Analysis of the aerodynamic performance of high-speed trains in special cuts would provide references for the critical overturning velocity and complement the operation safety management under strong winds.This work was conducted to investigate the flow structure around trains under different cut depths,slope angles using computational fluid dynamics(CFD).The high-speed train was considered with bogies and inter-carriage gaps.And the accuracy of the numerical method was validated by combining with the experimental data of wind tunnel tests.Then,the variations of aerodynamic forces and surface pressure distribution of the train were mainly analyzed.The results show that the surroundings of cuts along the railway line have a great effect on the crosswind stability of trains.With the slope angle and depth of the cut increasing,the coefficients of aerodynamic forces tend to reduce.An angle of 75°is chosen as the optimum one for the follow-up research.Under different depth conditions,the reasonable cut depth for high-speed trains to run safely is 3 m lower than that of the conventional cut whose slope ratio is 1:1.5.Furthermore,the windward slope angle is more important than the leeward one for the train aerodynamic performance.Due to the shield of appropriate cuts,the train body is in a minor positive pressure environment.Thus,designing a suitable cut can contribute to improving the operation safety of high-speed trains.
文摘Simulation-based mastery learning(SBML)is an emerging form of competencybased training that has been proposed as the next standard method for procedural task training,including that in gastr-ointestinal endoscopy.Current basic gastrointestinal endoscopy training relies on the number of procedures performed,and it has been criticized for its lack of objective standards that result in variable skills among trainees and its association with patient safety risk.Thus,incorporating simulators into a competency-based curriculum seems ideal for gastrointestinal endoscopy training.The curriculum for SBML in gastrointestinal endoscopy is currently being developed and has promising potential to translate into the clinical performance.Unlike the present apprenticeship model of“see one,do one,teach one,”SBML integrates a competency-based curriculum with specific learning objectives alongside simulation-based training.This allows trainees to practice essential skills repeatedly,receive feedback from experts,and gradually develop their abilities to achieve mastery.Moreover,trainees and trainers need to understand the learning targets of the program so that trainees can focus their learning on the necessary skills and trainers can provide structured feedback based on the expected outcomes.In addition to learning targets,an assessment plan is essential to provide trainees with future directions for their improvement and ensure patient safety by issuing a passing standard.Finally,the SBML program should be planned and managed by a specific team and conducted within a developed and tested curriculum.This review discusses the current state of gastr-ointestinal endoscopy training and the role of SBML in that field.
文摘To utilize exist SCADA(Supervisory Control and Data Acqui si tion)/EMS (Energy Management System) fully and economize capital, Henan Electric Power Dispatching and Communication Center in China established a set of Henan Dispatcher Training Simulator (HNDTS) base on its exist SCADA/EMS. In order to i ntegrated with exist SCADA/EMS, the integration method and technique are propose d. Graph data integration discussed with emphasis. After integration implemented , HNDTS can share all data with SCADA/EMS and dispatchers can be trained in same environment as real work situation, in the same time it can avoid amout of work of maintenance engineers. Both advantages and disadvantages of integration are analyzed. In the end of paper, the requirement for future DTS is put forward bas e on the experience of author.
文摘Simulating large-scale and complex systems is commonly considered a difficult and time-consuming task. In this paper, we propose a partial simulation way to speed up the simulation with real time demands. It is based on the idea that a train traffic diagram is expressed in a network, and through calculating the maximal long path in the network the simulation is done, but only within a particular partial area.Upon this, we let it become a problem oriented simulation. The simulation could be started at any time,from any trains or at any stations and stopped as the same way according to the problem to be concerned.We can use this kind of simulation to analyse or confirm the correctness of traffic schedule at a high speed to meet the real time demands.
文摘The simulator is a combination of computational functions describing physical system, distributed rule and knowledge bases, and a reasoning machine, all executing in parallel. The hardware,comprising two levels of multiprocessor network-- a T800 transputer and STD--BUS computer systems--and analogue and I/O boards, has been used successfully to train and simulate a 100 MW power system at a low cost. The system has wide applications in industry.
基金This work was supported by the Youth Backbone Teachers Training Program of Henan Colleges and Universities under Grant No.2016ggjs-287the Project of Science and Technology of Henan Province under Grant Nos.172102210124 and 202102210269.
文摘A multi-objective improved genetic algorithm is constructed to solve the train operation simulation model of urban rail train and find the optimal operation curve.In the train control system,the conversion point of operating mode is the basic of gene encoding and the chromosome composed of multiple genes represents a control scheme,and the initial population can be formed by the way.The fitness function can be designed by the design requirements of the train control stop error,time error and energy consumption.the effectiveness of new individual can be ensured by checking the validity of the original individual when its in the process of selection,crossover and mutation,and the optimal algorithm will be joined all the operators to make the new group not eliminate on the best individual of the last generation.The simulation result shows that the proposed genetic algorithm comparing with the optimized multi-particle simulation model can reduce more than 10%energy consumption,it can provide a large amount of sub-optimal solution and has obvious optimization effect.
文摘Objective To assess the face and construct validity of a full procedural transurethral prostate resection simulator ( TURPSimTM ) in training of transurethral resection of prostate. Methods Ten experienced and thirteen inexperienced urologists ( TURP experience ≥ 30 and
文摘Aim Toshorten integral design period of electric vehicles Methods The electric vehicle simulation program(EVSP), a modular user-friendly program which is written in Borland C++ OWL for Windows was developed. Results EVSP allows simulating the dynamic and the economy performance of electric vehicles.EVSP provides many kinds of data input module,a large components library of electric vehicles and several kinds of speed cycle with these library,it is easily to develop a new concept of different drive trains or even to compare or improve the existing electric vehicles. The paper simulated the performance of YW6120DD Electric Bus, and analyzed the test results comparing with simulation results Conclusion The simulation results indicate that the EVSP may contribute to the developments of electric vehicles in general and the definition of the optimal match management in the drive train in particular.
文摘BACKGROUND:There are several reasons why resuscitation measures may lead to inferior results:difficulties in team building,delayed realization of the emergency and interruption of chest compression.This study investigated the outcome of a new form of in-hospital cardiopulmonary resuscitation(CPR) training with special focus on changes in self-assurance of potential helpers when faced with emergency situations.METHODS:Following a 12-month period of CPR training,questionnaires were distributed to participants and non-participants.Those non-participants who intended to undergo the training at a later date served as control group.RESULTS:The study showed that participants experienced a significant improvement in selfassurance,compared with their remembered self-assurance before the training.Their self-assurance also was significantly greater than that of the control group of non-participants.CONCLUSION:Short lessons in CPR have an impact on the self-assurance of medical and non-medical personnel.
文摘Point-of-care ultrasound(POCUS)is a powerful diagnostic tool and provides treatment guidelines in acute critical settings.However,the limitation of using POCUS is operator dependent.Appropriate and validated training for acquiring and using skills in practice must be conducted before using POCUS in clinical settings in order to keep patients safe.Simulation education models have been introduced as a way to solve and overcome these concerns.However,the commercial simulator with sufficiently secured fidelity is expensive and not always available.This review focused on the inexpensive and easily made simulators for education on POCUS in critical specific situations related to the airway,breathing,circulation,and disability.We introduced the simulators that used non-infectious materials,with easily transportable features,and that had a sonographic appearance reproducibility similar to human tissue.We also introduced the recipe of each simulator in two parts:Materials surrounding disease simulators(surrounding materials)and specific disease simulators themselves(target simulators).This review article covered the following:endotracheal or oesophageal intubation,lung(A-lines,B-lines,lung sliding,and pleural effusions such as hemothorax),central vein access,pericardial fluid(cardiac tamponade),the structure related to the eyes,soft tissue abscess,nerve(regional nerve block),and skull fracture simulators.
文摘Diesel fuel combustion results in exhaust containing air pollutants and greenhouse gas emissions.Many railway vehicles use diesel fuel as their energy source.Exhaust emissions,as well as concerns about economical,alternative power supply,have driven efforts to move to hydrogen motive power.Hydrogen fuel cell technology applied to railways offers the opportunity to eliminate harmful exhaust emissions and the potential for a low-or zero-emission energy supply chain.Currently,only multiple-unit trains with hydrail technology operate commercially.Development of an Integrated Hybrid Train Simulator for intercity railway is presented.The proposed tool incorporates the effect of powertrain components during the wheel-to-tank process.Compared to its predecessors,the proposed reconfigurable tool provides high fidelity with medium requirements and minimum computation time.Single train simulation and the federal government’s Greenhouse gases,Regulated Emissions,and Energy use in Transportation(GREET)model are used in combination to evaluate the feasibility of various train and powertrain configurations.The Piedmont intercity service operating in North Carolina is used as a case study.The study includes six train configurations and powertrain options as well as nine hydrogen supply options in addition to the diesel supply.The results show that a hydrail option is not only feasible,but a low-or zero-carbon hydrogen supply chain could be possible.
文摘In modem four-stroke engine technology, variable valve timing and lift control offers potential benefits for making a high-performance engine. A novel electro-hydraulic fully variable valve train for four-stroke automotive engines is introduced. The construction of the nonlinear mathematic model of the valve train system and its dynamic analysis are also presented. Experimental and simulation results show that the novel electro-hydraulic valve train can achieve fully variable valve timing and lift control. Consequently the engine performance on different loads and speeds will be significantly increased. The technology also permits the elimination of the traditional throttle valve in the gasoline engines and increases engine design flexibility.
基金Project supported by the National Basic Research Program of China(Grant No.2012CB725400)the National Natural Science Foundation of China(Grant No.71131001-1)the Research Foundation of State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University,China(Grant Nos.RCS2012ZZ001 and RCS2012ZT001)
文摘In this paper, a new simulation approach for solving the mixed train scheduling problem on the high-speed double-track rail line is presented. Based on the discrete-time movement model, we propose control strategies for mixed train movement with different speeds on a high-speed double-track rail line, including braking strategy, priority rule, travelling strategy, and departing rule. A new detailed algorithm is also presented based on the proposed control strategies for mixed train movement. Moreover, we analyze the dynamic properties of rail traffic flow on a high-speed rail line. Using our proposed method, we can effectively simulate the mixed train schedule on a rail line. The numerical results demonstrate that an appropriate decrease of the departure interval can enhance the capacity, and a suitable increase of the distance between two adjacent stations can enhance the average speed. Meanwhile, the capacity and the average speed will be increased by appropriately enhancing the ratio of faster train number to slower train number from 1.
文摘Objectives:lnterprofessional collaboration in the training of nursing and psychology students helps provide students of both disciplines with the ability and competences they need to best attend to their patients.This study implemented and analyzed a method for developing the competences of each discipline in a scenario of joint clinical simulation that incorporates mental and physical health simultaneously,and measured the caring ability of the participating students.Methods:Participants took a self-applied survey measuring their own caring ability.After,a clinical simulation was performed where nursing students performed clinical interviews on psychology students,who acted as standardized patients.Caring abilities were measured in the nursing students,and the psychology students implemented an intervention service measuring caring ability and brief-debrief simulation by coaching to nursing students.Results:The results indicated that the self-applied questionnaire of caring ability resulted in scores significantly higher than what was measured by observers.Conclusions:The results contribute to the development of protocols,training and collaborative work practices in interprofessional education,which allow the scaling of these competences.
文摘Objective:To summarize and produce aggregated evidence on the effect of simulation-based teaching on skill performance in the nursing profession.Simulation is an active learning strategy involving the use of various resources to assimilate the real situation.It enables learners to improve their skills and knowledge in a coordinated environment.Methods:Systematic literature search of original research ar ticles was carried out through Google Scholar,Medline,and Cochrane Cumulative Index to Nursing and Allied Health Literature(CINAHL)databases.Studies conducted on simulation-based teaching and skill performance among nursing students or clinical nursing staff from 2010 to 2019,and published in the English language,were included in this study.Methodological quality was assessed by Joanna Briggs Institute,and the risk of bias was also assessed by Cochrane risk of bias and the risk of bias assessment tool for non-randomized studies(ROBINS-I)checklists.Results:Initially,638 titles were obtained from 3 sources,and 24 original studies with 2209 study par ticipants were taken for the final analysis.Of the total studies,14(58.3%)used single group prep post design,7(29.1%)used high fidelity simulator(HFS),and 7(29.1%)used a virtual simulator(VS).Twenty(83.3%)studies reported improved skill performance following simulation-based teaching.Simulation-based teaching improves skill performance among types of groups(single or double),study regions,high fidelity(HF),low fidelity(LF),and standard patient(SP)users.But the effect over virtual and medium fidelity simulators was not statistically significant.Overall,simulation-based teaching improves the skill performance score among the experimental group(d=1.01,95%confidence interval[CI][0.69–1.33],Z=6.18,P<0.01,93.9%).Significant heterogeneity and publication bias were observed during the pooled analysis.Conclusions:Simulation did improve skill performance among the intervention groups,but the conclusion is uncer tain due to the significant heterogeneity.The large extent of difference among original research has necessitated the development of well-defined assessment methods for skills and standardized simulation set-up for proper assessment of their effects.