Throughout the vehicle crash event, the interactions between vehicle, occupant, restraint system (VOR) are complicated and highly non-linear. CAE and physical tests are the most widely used in vehicle passive safety d...Throughout the vehicle crash event, the interactions between vehicle, occupant, restraint system (VOR) are complicated and highly non-linear. CAE and physical tests are the most widely used in vehicle passive safety development, but they can only be done with the detailed 3D model or physical samples. Often some design errors and imperfections are difficult to correct at that time, and a large amount of time will be needed. A restraint system concept design approach which based on single-degree-of-freedom occupant-vehicle model (SDOF) is proposed in this paper. The interactions between the restraint system parameters and the occupant responses in a crash are studied from the view of mechanics and energy. The discrete input and the iterative algorithm method are applied to the SDOF model to get the occupant responses quickly for arbitrary excitations (impact pulse) by MATLAB. By studying the relationships between the ridedown efficiency, the restraint stiffness, and the occupant response, the design principle of the restraint stiffness aiming to reduce occupant injury level during conceptual design is represented. Higher ridedown efficiency means more occupant energy absorbed by the vehicle, but the research result shows that higher ridedown efficiency does not mean lower occupant injury level. A proper restraint system design principle depends on two aspects. On one hand,the restraint system should lead to as high ridedown efficiency as possible, and at the same time, the restraint system should maximize use of the survival space to reduce the occupant deceleration level. As an example, an optimization of a passenger vehicle restraint system is designed by the concept design method above, and the final results are validated by MADYMO, which is the most widely used software in restraint system design, and the sled test. Consequently, a guideline and method for the occupant restraint system concept design is established in this paper.展开更多
Aim To study the influence of restraint system performance upon the occupant's response during impact, and provide a scientific base for occupant restraint system design. Methods \ In the light of basic th...Aim To study the influence of restraint system performance upon the occupant's response during impact, and provide a scientific base for occupant restraint system design. Methods \ In the light of basic theory of multibody system dynamics and impact dynamics on the basis of classical theory of impact, R W method is adopted to construct the vehicle occupant system model consisting of fourteen rigid bodies, thirty seven DOFs and slip joints for the simulation. A software named SVC3D(3 dimensional simulation of vehicle crash) is developed in the FORTRAN language. Results\ The results of simulation have a good coincidence with those of tests and the restraint system with low elongation webbing and equipped with pretensioner provides better restraint effect for the occupant. Conclusion\ The model of vehicle occupant multibody system and SVC3D are suitable for use. Occupant should be belted with low elongation webbing to a certain degree and occupant restraint system should be equipped with pretensioner.展开更多
Integrated into the development process of a chinese independent brand class sedan,optimization about occupant restraint system associated with dummy chest deceleration is studied.Based on this simulated vehicle decel...Integrated into the development process of a chinese independent brand class sedan,optimization about occupant restraint system associated with dummy chest deceleration is studied.Based on this simulated vehicle deceleration and the target vehicle′s chest deceleration,tipped equivalent square wave(TESW)is calculated by combining the average stiffness kof occupant restraint system and the average free flight time t*from the existant CNCAP(China new car assessment program)tested cars.After proposing modeling regulations of occupant restraint system and establishing mathematical dynamic modelling(MADYMO)for occupant restraint system of the target vehicle,four optimization design parameters namely vent area A,load limit L,seat belt extension ratio Band pretension force Fare selected by weighted injury criteria(WIC)rule and the first-order response surface method.The four parameters have been optimized by using orthogonal test design of four factors with five levels and the optimum combination A5L1B1F5 has been chosen by range and variance analyses.The results show that occupant restraint system performance has been optimized and improved,while meeting the chest deceleration calculation peak based on TESW.展开更多
To improve the passive safety of high-speed trains,it is very important to understand the mechanism of head injury in high-speed train collisions.In this study,the head injury mechanisms of occupants in high-speed tra...To improve the passive safety of high-speed trains,it is very important to understand the mechanism of head injury in high-speed train collisions.In this study,the head injury mechanisms of occupants in high-speed train rear-end collisions were investigated based on the occupant-seat coupling model,which included a dummy representing the Chinese 50th percentile adult male.The typical injury responses in terms of skull fractures,brain contusions,and diffuse axonal injury(DAI)were analyzed.Meanwhile,the influences of collision speed and seat parameters on head injury response were examined.The simulation results indicate that the skull fractures primarily occur at the skull base region due to excessive neck extension,while the brain contusions and DAI result from the relative displacement of different brain regions.The increase in collision speed will promote the probability of skull fracture,brain contusion,and DAI.Seat design modifications,such as reduced seat spacing,increased seat backrest angles,and selecting the appropriate cushion angle(76°)and friction coefficient(0.15),can effectively mitigate probably occupant's head injury.展开更多
An airbag is an effective protective device for vehicle occupant safety, but may cause unexpected injury from the excessive energy of ignition when it is deployed, This paper focuses on the design of a new tubular dri...An airbag is an effective protective device for vehicle occupant safety, but may cause unexpected injury from the excessive energy of ignition when it is deployed, This paper focuses on the design of a new tubular driver airhag from the perspective of reducing the dosage of gas generant, Three different dummies were selected for computer simulation to investigate the stiffness and protection performance of the new airhag, Next, a multi-objective optimization of the 50th percentile dummy was conducted, The results show that the static volume of the new airhag is only about 113 of the volume of an ordinary one, and the injury value of each type of dummy can meet legal requirements while reducing the gas dosage by at least 30%, The combined injury index （Pcomb） decreases by 22% and the gas dosage is reduced by 32% after optimization, This study demonstrates that the new tubular driver airbag has great potential for protection in terms of reducing the gas dosage,展开更多
To solve the constraints of multi-objective optimization of the driver system and high nonlinear problems, according to the relevant dimensions of a car, we build a simulation model with Hybrid Ⅲ 50th dummy driver co...To solve the constraints of multi-objective optimization of the driver system and high nonlinear problems, according to the relevant dimensions of a car, we build a simulation model with Hybrid Ⅲ 50th dummy driver constraint system. The comparison of the driver mechanics index of the experimental data with the simulation data in the frontal crash shows that the accuracy of simulation model meets the requirements. The optimal Latin test design is adopted, and the global sensitivity analysis of the design parameters is carried out based on the Kriging model. The four most sensitive parameters are selected, and the parameters are solved by a multi-island genetic algorithm.And then the nonlinear programming quadratic line(NLPQL) algorithm is used to search for accurate optimization. The optimal parameters of the occupant restraint system are determined: the limiting force value of force limiter 2 985.603 N, belt extension 12.684%, airbag point explosion time 27.585 ms, and airbag vent diameter 27.338 mm, with the weighted injury criterion(WIC) decreased by 12.97%, the head injury decreased by 22.60%, and the chest compression decreased by 7.29%. The results show that the system integration of passive safety devices such as seat belts and airbags can effectively protect the driver.展开更多
Fourteen SAE standards related to accommodation and occupant＇ packaging for vehicle interior are studied. The influencing factors, key reference accommodation points and major design dimensions and their relationship...Fourteen SAE standards related to accommodation and occupant＇ packaging for vehicle interior are studied. The influencing factors, key reference accommodation points and major design dimensions and their relationships of occupant packaging and ergonomics during the vehicle interior layout design and development are analyzed. Prototypes are presented to verify the results and how to achieve the packaging is shown. Auto- mobile designers can achieve significant practical guidance for human safety, efficiency accommodation and occupant packaging of all passengers during the vehicle design process.展开更多
This work explores three patterns of occupants’ control of window blinds and the potential influence on daylight performance of an office room in a tropical climate. In this climate, windows are frequently obstructe...This work explores three patterns of occupants’ control of window blinds and the potential influence on daylight performance of an office room in a tropical climate. In this climate, windows are frequently obstructed by curtains to avoid glare, despite the daylighting and the exterior view. The consequences are obstructed outside view, poor daylight quality and dependency on artificial lighting. This paper assesses the impact on available daylight using parametric analysis based on daylighting dynamic computer simulations using Grasshopper and Daysim software, combining WWR （window-to-wall ratio） （40% and 80%）, SVF （sky view factor） （small and large） and occupant behavior （active, intermediate and passive users）. The user patterns are based in an office buildings survey that identifies preferences concerning daylight use and control of shading devices. The daylight performance criteria combine UDI （useful daylight illuminance） （500-5,000 lux） and illuminance uniformity distribution. Results confirm the impact of occupant behavior on daylighting performance. The optimum combination of external shading devices, high SVF and high window size results in a useful daylighting for 1/3 of the time for passive users and 2/3 for active users.展开更多
The role that occupants have on energy consumption and performance of buildings is known,but still requires a great deal of research.In this paper,the most common techniques to detect occupancy and occupant behavior i...The role that occupants have on energy consumption and performance of buildings is known,but still requires a great deal of research.In this paper,the most common techniques to detect occupancy and occupant behavior in buildings are categorized with their advantages and disadvantages.Being the buildings characterized by different energy usage,the presentation of the studies that applied surveys and monitoring campaigns is conducted with differentiation between residential and office buildings.展开更多
Overpopulation globally is an addressed issue impacting human lives, marine lives, and the surrounding ecosystem;it is adding pressure on the available resources that should be optimized to suit the needs. Yet with im...Overpopulation globally is an addressed issue impacting human lives, marine lives, and the surrounding ecosystem;it is adding pressure on the available resources that should be optimized to suit the needs. Yet with improper management of resources and monitoring of daily activities, the environment will be further negatively impacted. With overpopulation higher urbanization rates are noticed with the demand of seeking better health facilities, better education, better jobs and better well-being;this progression is driving more demand into the infrastructure sector to be able to accommodate the growth rates. Hence, the need to having sustainable communities aiming at optimizing the resources used, working towards more feasible, environmentally friendly and cost-effective communities with a better occupant’s experience is in action. Sustainable development goals (SDG) are vital goals developed by the United Nations Development Program (UNDP) in 2015 to address and guide through 17 interconnected global goals serving the previously mentioned trend. Out of the 17 goals, Sustainable Cities and Communities (goal #11) and Good Health and Well-Being (goal #3) are the focus of this paper directed towards holding a comparative analysis between the community scale commonly known and mostly used rating system Leadership of Energy and Environmental Design (LEED-Cities and Communities) (USA) versus similar rating systems like Tarsheed-Communities (Egypt) and Estidama-Pearl (UAE) rating systems meeting sustainable development goal #11. Conjointly, another complimenting comparative review of the occupant’s health and wellbeing rating systems, such as Fitwel (USA) and Well (USA) are studied under sustainable development goal #3;however, they are focused on a building scale assessment. Living Community Challenge (LCC, USA) rating system linking community rating system with health & wellbeing credits was first issued in 2006, yet is it not cost effective neither easy to apply acting as a primary step while being affordable, accessible, and easy to implement. The objective of this paper is to highlight the pros and gaps under both categories of studies of community rating system and occupants’ health & wellbeing rating systems based on scientific content and commercial acceptance and do-ability. This comparison is done via comparing credits and sections within each rating system type;this will support in addressing the focal points needed for an integrated rating system between both categories that will serve in meeting SDG Sustainable Cities and Communities (goal #11) and Good Health and Well-Being (goal #3).展开更多
There has been no precise information regarding occupants’ status and their portion in traffic accident. By using traffic police information, epidemiological pattern of road traffic injuries among occupants’ vehicle...There has been no precise information regarding occupants’ status and their portion in traffic accident. By using traffic police information, epidemiological pattern of road traffic injuries among occupants’ vehicles was analyzed in 2012. It was a cross sectional study. In this study, traffic police registered data in 2012 were used. Subjects were all occupants who had accident record in 2012 (81585: 77841 injured and 3744 death). Before analyzing, various preparatory steps including data control and merging were done after which data were processed. Findings showed that the mean age of the studied population was 28.7 ± 15.11 years. The highest percentage of accident occurred among car and motorcycle occupants respectively. The risk of death among the injured aged 30 - 59 years and 60+ were 1.20 and 2.23 times more than 30 years (as reference) respectively (p < 0.001). Risk of death among the injured in high ways, main roads and rural roads was 2.84 times more than in urban roads (p < 0.001). The risk of death among the injured was 2 times higher in high ways, main roads and rural secondary roads than streets (p < 0.001). Hence car and motorcycle occupants need urgent attention especially in motorways and high ways, main roads and rural secondary.展开更多
To begin with, rating systems are a beneficial tool in determining the efficiency of a building’s ability to utilise its resources effectively. In this study, the two elements under comparison are the Building Rating...To begin with, rating systems are a beneficial tool in determining the efficiency of a building’s ability to utilise its resources effectively. In this study, the two elements under comparison are the Building Rating Systems (BRSs) and Occupant Rating Systems (ORSs). The main objective of this paper is to be able to examine the most commonly applied international and national BRS and ORS and, based on that, discover the possibility of developing an integration of both the BRS and ORS into one rating system. Quite simply, a BRS is a method by which buildings are assessed and given a score based on numerous features such as the efficiency of each of the services, total energy consumption, and alternate options of consumption. There are various BRSs that are implemented globally, each with its own set of criteria and specifications. Thus, based on the analysis of the benefits and drawbacks of both types of rating systems, it could be deduced that a well-rounded rating system with all technical and non-technical aspects combined would be beneficial to both the efficiency of the building as well as the building occupants’ health and well-being.展开更多
Building Performance Simulation(BPS)has been adopted as an essential tool for designing,operating,and retrofitting buildings to optimize energy efficiency throughout the building life cycle.The Green Building XML(gbXM...Building Performance Simulation(BPS)has been adopted as an essential tool for designing,operating,and retrofitting buildings to optimize energy efficiency throughout the building life cycle.The Green Building XML(gbXML)schema facilitates seamless data exchange between Building Information Modeling(BIM)and Building Energy Modeling(BEM)software tools.However,limited occupant behavior(OB)representation in BIM often leads to inconsistent and inaccurate energy simulation in BEM software.This paper presents 154 systematic enhancements to the existing occupant behavior XML(obXML)schema v1.3.4,initially developed for standardizing OB representation for BEM,to address existing limitations and improve interoperability with BIM models.The enhancements encompass improved integration with BIM models through extended building representations and system operations,expanded support for advanced OB models with additional environmental parameters and mathematical capabilities,and implementation of a standardized model documentation framework.To facilitate seamless data transformation between gbXML and obXML schemas,we developed a publicly available gb-obXML Schema Converter.Three case studies demonstrate the enhanced schema’s capabilities:representation of building information using a two-story office building model,documentation of a window operation behavior model,and validation of the schema converter’s functionality.The enhanced obXML schema v1.4 enables sophisticated modeling of occupant-building interactions while maintaining consistency with industry-standard BIM schemas.The standardized documentation framework facilitates reproducibility and knowledge sharing in the OB research community,while the schema converter automates the integration of building information into OB simulation workflows.These enhancements establish a foundation for more accurate building performance simulation by supporting sophisticated representation of occupant behavior within the BIM-to-BEM simulation workflows.展开更多
A high-quality indoor environment is essential for ensuring occupant comfort and health.Conventional heating,ventilation,and air conditioning(HVAC)systems,which are designed under the most unfavorable conditions with ...A high-quality indoor environment is essential for ensuring occupant comfort and health.Conventional heating,ventilation,and air conditioning(HVAC)systems,which are designed under the most unfavorable conditions with lumped parameter approaches,often lead to energy waste.To address this problem,an occupant-oriented indoor environment-creation framework is presented.The system identifies occupant distribution and usage scenarios through an occupant positioning system.Based on the occupant distribution,the system switches air distribution patterns and adjusts air supply parameters to supply air to occupied zones efficiently.This perspective paper presents the key technologies involved and outlines future research directions in this field.The key technologies and the future roadmap are introduced.This perspective will help address research gaps and inspire ideas to create occupant-oriented environments for more healthy,comfortable,energy-saving,and low-carbon indoor environments.展开更多
In the development of side-impact safety performance in automobiles,the injury conditions of far-side occupants have gradually been incorporated into the evaluation system of automotive safety in China.This study,base...In the development of side-impact safety performance in automobiles,the injury conditions of far-side occupants have gradually been incorporated into the evaluation system of automotive safety in China.This study,based on three side-impact conditions in the Chinese automotive safety assessment system,employs the finite element method to analyze the injury and motion characteristics of far-side occupants under various impact scenarios.The results indicate that in the C-NCAP 75°POLE condition,certain impact areas of the far-side dummy sustain more severe injuries.These findings provide data references for the development of safety performance measures aimed at protecting far-side occupants.展开更多
Occupants are the core of the built environment.Traditional heating,ventilation,and air-conditioning(HVAC)systems operate with predefined schedules and maximum occupancy assumptions with no consideration of specific o...Occupants are the core of the built environment.Traditional heating,ventilation,and air-conditioning(HVAC)systems operate with predefined schedules and maximum occupancy assumptions with no consideration of specific occupant information.These generalized assumptions usually do not align with the actual demand and result in over-conditioning and occupant discomfort.In recent years,with the aid of Information&Communication Technology(ICT)and Computer Science(CS),it is possible to acquire real-time and accurate occupant information to satisfy the exact thermal requirement through specific HVAC control in one particular built environment.This mechanism is called HVAC“Occupant-centric Control(OCC).”HVAC OCC strategy starts with collecting the occupant’s information(e.g.,presence/absence)and then applies it to meet the occupant’s requirement(e.g.,thermal comfort).However,even though some research studies and field pilot demonstrations have been devoted to the field of OCC,there is a lack of systematic knowledge about occupant data,which is the principal component of OCC for HVAC researchers and practitioners.To fill this gap,this review paper discusses OCC with a particular emphasis on occupant information and investigates how this information can assist HVAC operation in providing an acceptable built environment in required spaces during the required time.We provide a fine-grained,comprehensive picture of occupant information,discuss its features,the modalities of information feed-in into the HVAC control,and the application of commonly utilized occupant information for OCC.展开更多
Occupant behavior largely influence the energy use within buildings.In the multi-occupant office,occupant behavior is affected by individual preference as well as the interaction among occupants,and yet no suitable mo...Occupant behavior largely influence the energy use within buildings.In the multi-occupant office,occupant behavior is affected by individual preference as well as the interaction among occupants,and yet no suitable model is available to precisely reflect the behavior characteristics.This paper proposed and introduced a method for innovative multi-occupant air-conditioning(AC)usage behavior modelling in a multi-occupant office,which used intuitionistic fuzzy preference relationship to describe individual behavior intention and a hierarchical structure to reflect the social relationship among multiple occupants through subjective evaluation method.The group decision-making process combined the individual behavior intention and the weights of occupants using the analytic hierarchy process.Then,the AC usage behavior of a multi-occupant office was simulated by integrating the multi-occupant model into designer’s simulation toolkit(DeST)building performance simulation software.The results of conducted analysis of a single office with multi-occupant showed that the proposed multi-occupant modelling method could quantitatively characterize the group relationships and AC usage behavior patterns.The absolute errors for the total AC operation time and frequency of the start-up periods of AC between the simulation and measurement results were only 2.7%and 2.0%,respectively.Thus,the proposed multi-occupant modelling method could realize a relatively accurate simulation of the multi-occupant behavior.展开更多
Occupant-centric control(OCC)is intelligent control of building systems based on the real comfort needs of occupants.This paper provides a comprehensive review of how real-world data on energy-related occupant behavio...Occupant-centric control(OCC)is intelligent control of building systems based on the real comfort needs of occupants.This paper provides a comprehensive review of how real-world data on energy-related occupant behavior(OB)can be integrated and applied in OCC systems.The aim is to accurately portray the real occupant needs and improve energy efficiency without sacrificing occupant comfort.This paper first introduces two types of OB:detailed occupancy states and energy-interaction behaviors,including methods to monitor,establish,and predict these OB.Then,OCC is divided into real-time control and model-based predictive control,and each of these four scenarios is discussed.It extensively reviews OCC methods for different equipment in four cases,covering control strategies,control scales,comfort enhancement scenarios,and energy-saving potential for each category.It is summarized that despite extensive research on OB,there are still significant challenges in integrating this research into OCC.A major issue is the lack of a bridge connecting monitoring acquired information and controls.In addition,the article reviews the current state of OCC platform development.The future direction should be combined with advanced Internet of Things(IoT)technologies,WiFi,and other communication technologies to obtain information about people’s behavior and real needs in order to create truly energy efficient and comfortable smart environments.The article also discusses how enhancing the real-time feedback capability of the OCC system can help improve the overall control system capability and the importance of testing through experimentation.展开更多
A critical gap between the occupant behaviour research field and the building engineering practice limits the integration of occupant-centric strategies into simulation-aided building design and operation.Closing this...A critical gap between the occupant behaviour research field and the building engineering practice limits the integration of occupant-centric strategies into simulation-aided building design and operation.Closing this gap would contribute to the implementation of strategies that improve the occupants’well-being while reducing the buildings’environmental footprint.In this view,it is urgent to develop guidelines,standardised methods,and supporting tools that facilitate the integration of advanced occupant behaviour models into the simulation studies.One important step that needs to be fully integrated into the simulation workflow is the identification of influential and non-influential occupant behaviour aspects for a given simulation problem.Accordingly,this article advances and demonstrates the application of the Impact Indices method,a fast and efficient method for screening the potential impact of occupant behaviour on the heating and cooling demand.Specifically,the method now allows the calculation of Impact Indices quantifying the sensitivity of building energy use to occupancy,lighting use,plug-load appliances use,and blind operation at any spatial and temporal resolution.Hence,users can apply it in more detailed heating and cooling scenarios without losing information.Furthermore,they can identify which components in building design and operation require more sophisticated occupant behaviour models.An office building is used as a real case study to illustrate the application of the method and asses its performance against a one-factor-at-a-time sensitivity analysis.The Impact Indices method indicates that occupancy,lighting use and plug-load appliances have the greatest impact on the annual cooling demand of the studied office building;blind operation is influential only in the west and south façades of the building.Finally,potential applications of the method in building design and operation practice are discussed.展开更多
By applying the rules set in traffic flow and pedestrian flow models, a basic cellular automata model is presented to simulate occupant evacuation in fire. Some extended models are introduced to study the special phen...By applying the rules set in traffic flow and pedestrian flow models, a basic cellular automata model is presented to simulate occupant evacuation in fire. Some extended models are introduced to study the special phenomena of evacuation from the fire room. The key of the models is the introduction of the danger grade which makes the route choice convenient and reasonable. Fire not only influences the emotional and behavioral characteristics of an individual but also affects his physical constitution, which reduces his maximal possible velocity. The models consider these influence factors by applying a set of simple but effective rules. It is needed to emphasize that all rules are established according to the essential phenomenon in fire evacuation, that is, all the occupants would try to move to the safest place as fast as possible. Some simulation examples are also presented to validate the applicability of the models.展开更多
基金supported by National Natural Science Foundation of China (Grant No. 51075180)Open Foundation of State Key Laboratory of Vehicle NVH and Safety Technology of China (Grant No.NVHSKL-201013)
文摘Throughout the vehicle crash event, the interactions between vehicle, occupant, restraint system (VOR) are complicated and highly non-linear. CAE and physical tests are the most widely used in vehicle passive safety development, but they can only be done with the detailed 3D model or physical samples. Often some design errors and imperfections are difficult to correct at that time, and a large amount of time will be needed. A restraint system concept design approach which based on single-degree-of-freedom occupant-vehicle model (SDOF) is proposed in this paper. The interactions between the restraint system parameters and the occupant responses in a crash are studied from the view of mechanics and energy. The discrete input and the iterative algorithm method are applied to the SDOF model to get the occupant responses quickly for arbitrary excitations (impact pulse) by MATLAB. By studying the relationships between the ridedown efficiency, the restraint stiffness, and the occupant response, the design principle of the restraint stiffness aiming to reduce occupant injury level during conceptual design is represented. Higher ridedown efficiency means more occupant energy absorbed by the vehicle, but the research result shows that higher ridedown efficiency does not mean lower occupant injury level. A proper restraint system design principle depends on two aspects. On one hand,the restraint system should lead to as high ridedown efficiency as possible, and at the same time, the restraint system should maximize use of the survival space to reduce the occupant deceleration level. As an example, an optimization of a passenger vehicle restraint system is designed by the concept design method above, and the final results are validated by MADYMO, which is the most widely used software in restraint system design, and the sled test. Consequently, a guideline and method for the occupant restraint system concept design is established in this paper.
文摘Aim To study the influence of restraint system performance upon the occupant's response during impact, and provide a scientific base for occupant restraint system design. Methods \ In the light of basic theory of multibody system dynamics and impact dynamics on the basis of classical theory of impact, R W method is adopted to construct the vehicle occupant system model consisting of fourteen rigid bodies, thirty seven DOFs and slip joints for the simulation. A software named SVC3D(3 dimensional simulation of vehicle crash) is developed in the FORTRAN language. Results\ The results of simulation have a good coincidence with those of tests and the restraint system with low elongation webbing and equipped with pretensioner provides better restraint effect for the occupant. Conclusion\ The model of vehicle occupant multibody system and SVC3D are suitable for use. Occupant should be belted with low elongation webbing to a certain degree and occupant restraint system should be equipped with pretensioner.
基金supported by the National Science and Technology Support Program of China(2011BAG02B02)
文摘Integrated into the development process of a chinese independent brand class sedan,optimization about occupant restraint system associated with dummy chest deceleration is studied.Based on this simulated vehicle deceleration and the target vehicle′s chest deceleration,tipped equivalent square wave(TESW)is calculated by combining the average stiffness kof occupant restraint system and the average free flight time t*from the existant CNCAP(China new car assessment program)tested cars.After proposing modeling regulations of occupant restraint system and establishing mathematical dynamic modelling(MADYMO)for occupant restraint system of the target vehicle,four optimization design parameters namely vent area A,load limit L,seat belt extension ratio Band pretension force Fare selected by weighted injury criteria(WIC)rule and the first-order response surface method.The four parameters have been optimized by using orthogonal test design of four factors with five levels and the optimum combination A5L1B1F5 has been chosen by range and variance analyses.The results show that occupant restraint system performance has been optimized and improved,while meeting the chest deceleration calculation peak based on TESW.
基金supported by the National Natural Science Foundation of China(Grant No.12122211)the Natural Science Foundation of Sichuan Province(Grant No.2022NSFSC0035)。
文摘To improve the passive safety of high-speed trains,it is very important to understand the mechanism of head injury in high-speed train collisions.In this study,the head injury mechanisms of occupants in high-speed train rear-end collisions were investigated based on the occupant-seat coupling model,which included a dummy representing the Chinese 50th percentile adult male.The typical injury responses in terms of skull fractures,brain contusions,and diffuse axonal injury(DAI)were analyzed.Meanwhile,the influences of collision speed and seat parameters on head injury response were examined.The simulation results indicate that the skull fractures primarily occur at the skull base region due to excessive neck extension,while the brain contusions and DAI result from the relative displacement of different brain regions.The increase in collision speed will promote the probability of skull fracture,brain contusion,and DAI.Seat design modifications,such as reduced seat spacing,increased seat backrest angles,and selecting the appropriate cushion angle(76°)and friction coefficient(0.15),can effectively mitigate probably occupant's head injury.
文摘An airbag is an effective protective device for vehicle occupant safety, but may cause unexpected injury from the excessive energy of ignition when it is deployed, This paper focuses on the design of a new tubular driver airhag from the perspective of reducing the dosage of gas generant, Three different dummies were selected for computer simulation to investigate the stiffness and protection performance of the new airhag, Next, a multi-objective optimization of the 50th percentile dummy was conducted, The results show that the static volume of the new airhag is only about 113 of the volume of an ordinary one, and the injury value of each type of dummy can meet legal requirements while reducing the gas dosage by at least 30%, The combined injury index （Pcomb） decreases by 22% and the gas dosage is reduced by 32% after optimization, This study demonstrates that the new tubular driver airbag has great potential for protection in terms of reducing the gas dosage,
基金Supported by Natural Science and Technology Research Project of the Jiangxi Education Department(GJJ202002, GJJ2202620)。
文摘To solve the constraints of multi-objective optimization of the driver system and high nonlinear problems, according to the relevant dimensions of a car, we build a simulation model with Hybrid Ⅲ 50th dummy driver constraint system. The comparison of the driver mechanics index of the experimental data with the simulation data in the frontal crash shows that the accuracy of simulation model meets the requirements. The optimal Latin test design is adopted, and the global sensitivity analysis of the design parameters is carried out based on the Kriging model. The four most sensitive parameters are selected, and the parameters are solved by a multi-island genetic algorithm.And then the nonlinear programming quadratic line(NLPQL) algorithm is used to search for accurate optimization. The optimal parameters of the occupant restraint system are determined: the limiting force value of force limiter 2 985.603 N, belt extension 12.684%, airbag point explosion time 27.585 ms, and airbag vent diameter 27.338 mm, with the weighted injury criterion(WIC) decreased by 12.97%, the head injury decreased by 22.60%, and the chest compression decreased by 7.29%. The results show that the system integration of passive safety devices such as seat belts and airbags can effectively protect the driver.
基金the National Natural Science Foundation of China (19832020)National Outstanding Youth Science Foundation of China(10125208)
文摘Fourteen SAE standards related to accommodation and occupant＇ packaging for vehicle interior are studied. The influencing factors, key reference accommodation points and major design dimensions and their relationships of occupant packaging and ergonomics during the vehicle interior layout design and development are analyzed. Prototypes are presented to verify the results and how to achieve the packaging is shown. Auto- mobile designers can achieve significant practical guidance for human safety, efficiency accommodation and occupant packaging of all passengers during the vehicle design process.
文摘This work explores three patterns of occupants’ control of window blinds and the potential influence on daylight performance of an office room in a tropical climate. In this climate, windows are frequently obstructed by curtains to avoid glare, despite the daylighting and the exterior view. The consequences are obstructed outside view, poor daylight quality and dependency on artificial lighting. This paper assesses the impact on available daylight using parametric analysis based on daylighting dynamic computer simulations using Grasshopper and Daysim software, combining WWR （window-to-wall ratio） （40% and 80%）, SVF （sky view factor） （small and large） and occupant behavior （active, intermediate and passive users）. The user patterns are based in an office buildings survey that identifies preferences concerning daylight use and control of shading devices. The daylight performance criteria combine UDI （useful daylight illuminance） （500-5,000 lux） and illuminance uniformity distribution. Results confirm the impact of occupant behavior on daylighting performance. The optimum combination of external shading devices, high SVF and high window size results in a useful daylighting for 1/3 of the time for passive users and 2/3 for active users.
文摘The role that occupants have on energy consumption and performance of buildings is known,but still requires a great deal of research.In this paper,the most common techniques to detect occupancy and occupant behavior in buildings are categorized with their advantages and disadvantages.Being the buildings characterized by different energy usage,the presentation of the studies that applied surveys and monitoring campaigns is conducted with differentiation between residential and office buildings.
文摘Overpopulation globally is an addressed issue impacting human lives, marine lives, and the surrounding ecosystem;it is adding pressure on the available resources that should be optimized to suit the needs. Yet with improper management of resources and monitoring of daily activities, the environment will be further negatively impacted. With overpopulation higher urbanization rates are noticed with the demand of seeking better health facilities, better education, better jobs and better well-being;this progression is driving more demand into the infrastructure sector to be able to accommodate the growth rates. Hence, the need to having sustainable communities aiming at optimizing the resources used, working towards more feasible, environmentally friendly and cost-effective communities with a better occupant’s experience is in action. Sustainable development goals (SDG) are vital goals developed by the United Nations Development Program (UNDP) in 2015 to address and guide through 17 interconnected global goals serving the previously mentioned trend. Out of the 17 goals, Sustainable Cities and Communities (goal #11) and Good Health and Well-Being (goal #3) are the focus of this paper directed towards holding a comparative analysis between the community scale commonly known and mostly used rating system Leadership of Energy and Environmental Design (LEED-Cities and Communities) (USA) versus similar rating systems like Tarsheed-Communities (Egypt) and Estidama-Pearl (UAE) rating systems meeting sustainable development goal #11. Conjointly, another complimenting comparative review of the occupant’s health and wellbeing rating systems, such as Fitwel (USA) and Well (USA) are studied under sustainable development goal #3;however, they are focused on a building scale assessment. Living Community Challenge (LCC, USA) rating system linking community rating system with health & wellbeing credits was first issued in 2006, yet is it not cost effective neither easy to apply acting as a primary step while being affordable, accessible, and easy to implement. The objective of this paper is to highlight the pros and gaps under both categories of studies of community rating system and occupants’ health & wellbeing rating systems based on scientific content and commercial acceptance and do-ability. This comparison is done via comparing credits and sections within each rating system type;this will support in addressing the focal points needed for an integrated rating system between both categories that will serve in meeting SDG Sustainable Cities and Communities (goal #11) and Good Health and Well-Being (goal #3).
文摘There has been no precise information regarding occupants’ status and their portion in traffic accident. By using traffic police information, epidemiological pattern of road traffic injuries among occupants’ vehicles was analyzed in 2012. It was a cross sectional study. In this study, traffic police registered data in 2012 were used. Subjects were all occupants who had accident record in 2012 (81585: 77841 injured and 3744 death). Before analyzing, various preparatory steps including data control and merging were done after which data were processed. Findings showed that the mean age of the studied population was 28.7 ± 15.11 years. The highest percentage of accident occurred among car and motorcycle occupants respectively. The risk of death among the injured aged 30 - 59 years and 60+ were 1.20 and 2.23 times more than 30 years (as reference) respectively (p < 0.001). Risk of death among the injured in high ways, main roads and rural roads was 2.84 times more than in urban roads (p < 0.001). The risk of death among the injured was 2 times higher in high ways, main roads and rural secondary roads than streets (p < 0.001). Hence car and motorcycle occupants need urgent attention especially in motorways and high ways, main roads and rural secondary.
文摘To begin with, rating systems are a beneficial tool in determining the efficiency of a building’s ability to utilise its resources effectively. In this study, the two elements under comparison are the Building Rating Systems (BRSs) and Occupant Rating Systems (ORSs). The main objective of this paper is to be able to examine the most commonly applied international and national BRS and ORS and, based on that, discover the possibility of developing an integration of both the BRS and ORS into one rating system. Quite simply, a BRS is a method by which buildings are assessed and given a score based on numerous features such as the efficiency of each of the services, total energy consumption, and alternate options of consumption. There are various BRSs that are implemented globally, each with its own set of criteria and specifications. Thus, based on the analysis of the benefits and drawbacks of both types of rating systems, it could be deduced that a well-rounded rating system with all technical and non-technical aspects combined would be beneficial to both the efficiency of the building as well as the building occupants’ health and well-being.
文摘Building Performance Simulation(BPS)has been adopted as an essential tool for designing,operating,and retrofitting buildings to optimize energy efficiency throughout the building life cycle.The Green Building XML(gbXML)schema facilitates seamless data exchange between Building Information Modeling(BIM)and Building Energy Modeling(BEM)software tools.However,limited occupant behavior(OB)representation in BIM often leads to inconsistent and inaccurate energy simulation in BEM software.This paper presents 154 systematic enhancements to the existing occupant behavior XML(obXML)schema v1.3.4,initially developed for standardizing OB representation for BEM,to address existing limitations and improve interoperability with BIM models.The enhancements encompass improved integration with BIM models through extended building representations and system operations,expanded support for advanced OB models with additional environmental parameters and mathematical capabilities,and implementation of a standardized model documentation framework.To facilitate seamless data transformation between gbXML and obXML schemas,we developed a publicly available gb-obXML Schema Converter.Three case studies demonstrate the enhanced schema’s capabilities:representation of building information using a two-story office building model,documentation of a window operation behavior model,and validation of the schema converter’s functionality.The enhanced obXML schema v1.4 enables sophisticated modeling of occupant-building interactions while maintaining consistency with industry-standard BIM schemas.The standardized documentation framework facilitates reproducibility and knowledge sharing in the OB research community,while the schema converter automates the integration of building information into OB simulation workflows.These enhancements establish a foundation for more accurate building performance simulation by supporting sophisticated representation of occupant behavior within the BIM-to-BEM simulation workflows.
基金supported by the National Natural Science Foundation of China(Grant No.52178078)the Key Laboratory of Eco Planning&Green Building,Ministry of Education(Tsinghua University),Beijing,China.
文摘A high-quality indoor environment is essential for ensuring occupant comfort and health.Conventional heating,ventilation,and air conditioning(HVAC)systems,which are designed under the most unfavorable conditions with lumped parameter approaches,often lead to energy waste.To address this problem,an occupant-oriented indoor environment-creation framework is presented.The system identifies occupant distribution and usage scenarios through an occupant positioning system.Based on the occupant distribution,the system switches air distribution patterns and adjusts air supply parameters to supply air to occupied zones efficiently.This perspective paper presents the key technologies involved and outlines future research directions in this field.The key technologies and the future roadmap are introduced.This perspective will help address research gaps and inspire ideas to create occupant-oriented environments for more healthy,comfortable,energy-saving,and low-carbon indoor environments.
文摘In the development of side-impact safety performance in automobiles,the injury conditions of far-side occupants have gradually been incorporated into the evaluation system of automotive safety in China.This study,based on three side-impact conditions in the Chinese automotive safety assessment system,employs the finite element method to analyze the injury and motion characteristics of far-side occupants under various impact scenarios.The results indicate that in the C-NCAP 75°POLE condition,certain impact areas of the far-side dummy sustain more severe injuries.These findings provide data references for the development of safety performance measures aimed at protecting far-side occupants.
基金supported by the U.S.Department of Energy through the Building America program under award number DE-EE0008694.
文摘Occupants are the core of the built environment.Traditional heating,ventilation,and air-conditioning(HVAC)systems operate with predefined schedules and maximum occupancy assumptions with no consideration of specific occupant information.These generalized assumptions usually do not align with the actual demand and result in over-conditioning and occupant discomfort.In recent years,with the aid of Information&Communication Technology(ICT)and Computer Science(CS),it is possible to acquire real-time and accurate occupant information to satisfy the exact thermal requirement through specific HVAC control in one particular built environment.This mechanism is called HVAC“Occupant-centric Control(OCC).”HVAC OCC strategy starts with collecting the occupant’s information(e.g.,presence/absence)and then applies it to meet the occupant’s requirement(e.g.,thermal comfort).However,even though some research studies and field pilot demonstrations have been devoted to the field of OCC,there is a lack of systematic knowledge about occupant data,which is the principal component of OCC for HVAC researchers and practitioners.To fill this gap,this review paper discusses OCC with a particular emphasis on occupant information and investigates how this information can assist HVAC operation in providing an acceptable built environment in required spaces during the required time.We provide a fine-grained,comprehensive picture of occupant information,discuss its features,the modalities of information feed-in into the HVAC control,and the application of commonly utilized occupant information for OCC.
基金This study was supported by the National Natural Science Founda-tion of China(Grant no.51978481)。
文摘Occupant behavior largely influence the energy use within buildings.In the multi-occupant office,occupant behavior is affected by individual preference as well as the interaction among occupants,and yet no suitable model is available to precisely reflect the behavior characteristics.This paper proposed and introduced a method for innovative multi-occupant air-conditioning(AC)usage behavior modelling in a multi-occupant office,which used intuitionistic fuzzy preference relationship to describe individual behavior intention and a hierarchical structure to reflect the social relationship among multiple occupants through subjective evaluation method.The group decision-making process combined the individual behavior intention and the weights of occupants using the analytic hierarchy process.Then,the AC usage behavior of a multi-occupant office was simulated by integrating the multi-occupant model into designer’s simulation toolkit(DeST)building performance simulation software.The results of conducted analysis of a single office with multi-occupant showed that the proposed multi-occupant modelling method could quantitatively characterize the group relationships and AC usage behavior patterns.The absolute errors for the total AC operation time and frequency of the start-up periods of AC between the simulation and measurement results were only 2.7%and 2.0%,respectively.Thus,the proposed multi-occupant modelling method could realize a relatively accurate simulation of the multi-occupant behavior.
基金funded by“A Project(Key grant)Supported by the Scientific Research Fund of Hunan Provincial Education Department,China(No.23A0033)”support was provided by“A Project Supported by the Scientific Research Fund of Hunan Provincial Education Department,China(No.2023JGZD027)”.
文摘Occupant-centric control(OCC)is intelligent control of building systems based on the real comfort needs of occupants.This paper provides a comprehensive review of how real-world data on energy-related occupant behavior(OB)can be integrated and applied in OCC systems.The aim is to accurately portray the real occupant needs and improve energy efficiency without sacrificing occupant comfort.This paper first introduces two types of OB:detailed occupancy states and energy-interaction behaviors,including methods to monitor,establish,and predict these OB.Then,OCC is divided into real-time control and model-based predictive control,and each of these four scenarios is discussed.It extensively reviews OCC methods for different equipment in four cases,covering control strategies,control scales,comfort enhancement scenarios,and energy-saving potential for each category.It is summarized that despite extensive research on OB,there are still significant challenges in integrating this research into OCC.A major issue is the lack of a bridge connecting monitoring acquired information and controls.In addition,the article reviews the current state of OCC platform development.The future direction should be combined with advanced Internet of Things(IoT)technologies,WiFi,and other communication technologies to obtain information about people’s behavior and real needs in order to create truly energy efficient and comfortable smart environments.The article also discusses how enhancing the real-time feedback capability of the OCC system can help improve the overall control system capability and the importance of testing through experimentation.
文摘A critical gap between the occupant behaviour research field and the building engineering practice limits the integration of occupant-centric strategies into simulation-aided building design and operation.Closing this gap would contribute to the implementation of strategies that improve the occupants’well-being while reducing the buildings’environmental footprint.In this view,it is urgent to develop guidelines,standardised methods,and supporting tools that facilitate the integration of advanced occupant behaviour models into the simulation studies.One important step that needs to be fully integrated into the simulation workflow is the identification of influential and non-influential occupant behaviour aspects for a given simulation problem.Accordingly,this article advances and demonstrates the application of the Impact Indices method,a fast and efficient method for screening the potential impact of occupant behaviour on the heating and cooling demand.Specifically,the method now allows the calculation of Impact Indices quantifying the sensitivity of building energy use to occupancy,lighting use,plug-load appliances use,and blind operation at any spatial and temporal resolution.Hence,users can apply it in more detailed heating and cooling scenarios without losing information.Furthermore,they can identify which components in building design and operation require more sophisticated occupant behaviour models.An office building is used as a real case study to illustrate the application of the method and asses its performance against a one-factor-at-a-time sensitivity analysis.The Impact Indices method indicates that occupancy,lighting use and plug-load appliances have the greatest impact on the annual cooling demand of the studied office building;blind operation is influential only in the west and south façades of the building.Finally,potential applications of the method in building design and operation practice are discussed.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 50006012)the Chinese NKBRSF project (Grant No. 2001CB409600)the project of high-level university establishment.
文摘By applying the rules set in traffic flow and pedestrian flow models, a basic cellular automata model is presented to simulate occupant evacuation in fire. Some extended models are introduced to study the special phenomena of evacuation from the fire room. The key of the models is the introduction of the danger grade which makes the route choice convenient and reasonable. Fire not only influences the emotional and behavioral characteristics of an individual but also affects his physical constitution, which reduces his maximal possible velocity. The models consider these influence factors by applying a set of simple but effective rules. It is needed to emphasize that all rules are established according to the essential phenomenon in fire evacuation, that is, all the occupants would try to move to the safest place as fast as possible. Some simulation examples are also presented to validate the applicability of the models.
