1,674,915 research outputs found

    Vision-based active safety system for automatic stopping

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    ntelligent systems designed to reduce highway fatalities have been widely applied in the automotive sector in the last decade. Of all users of transport systems, pedestrians are the most vulnerable in crashes as they are unprotected. This paper deals with an autonomous intelligent emergency system designed to avoid collisions with pedestrians. The system consists of a fuzzy controller based on the time-to-collision estimate – obtained via a vision-based system – and the wheel-locking probability – obtained via the vehicle’s CAN bus – that generates a safe braking action. The system has been tested in a real car – a convertible Citroën C3 Pluriel – equipped with an automated electro-hydraulic braking system capable of working in parallel with the vehicle’s original braking circuit. The system is used as a last resort in the case that an unexpected pedestrian is in the lane and all the warnings have failed to produce a response from the driver

    Active heat exchange system development for latent heat thermal energy storage

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    Active heat exchange concepts for use with thermal energy storage systems in the temperature range of 250 C to 350 C, using the heat of fusion of molten salts for storing thermal energy are described. Salt mixtures that freeze and melt in appropriate ranges are identified and are evaluated for physico-chemical, economic, corrosive and safety characteristics. Eight active heat exchange concepts for heat transfer during solidification are conceived and conceptually designed for use with selected storage media. The concepts are analyzed for their scalability, maintenance, safety, technological development and costs. A model for estimating and scaling storage system costs is developed and is used for economic evaluation of salt mixtures and heat exchange concepts for a large scale application. The importance of comparing salts and heat exchange concepts on a total system cost basis, rather than the component cost basis alone, is pointed out. The heat exchange concepts were sized and compared for 6.5 MPa/281 C steam conditions and a 1000 MW(t) heat rate for six hours. A cost sensitivity analysis for other design conditions is also carried out

    Air Traffic Management Safety Challenges

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    The primary goal of the Air Traffic Management (ATM) system is to control accident risk. ATM safety has improved over the decades for many reasons, from better equipment to additional safety defences. But ATM safety targets, improving on current performance, are now extremely demanding. Safety analysts and aviation decision-makers have to make safety assessments based on statistically incomplete evidence. If future risks cannot be estimated with precision, then how is safety to be assured with traffic growth and operational/technical changes? What are the design implications for the USA’s ‘Next Generation Air Transportation System’ (NextGen) and Europe’s Single European Sky ATM Research Programme (SESAR)? ATM accident precursors arise from (eg) pilot/controller workload, miscommunication, and lack of upto- date information. Can these accident precursors confidently be ‘designed out’ by (eg) better system knowledge across ATM participants, automatic safety checks, and machine rather than voice communication? Future potentially hazardous situations could be as ‘messy’ in system terms as the Überlingen mid-air collision. Are ATM safety regulation policies fit for purpose: is it more and more difficult to innovate, to introduce new technologies and novel operational concepts? Must regulators be more active, eg more inspections and monitoring of real operational and organisational practices

    Subchronic Toxicity of Green Algae (Spyrogyra SP.) Ethanolic Extract on Hematologic Parameters

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    Green Algae, an organism with active substance such as phytomelatonin, has potential to be developed as Indonesian traditional medicine. As the long term addition of Green Algae ethanol extract (Ekstrak etanol ganggang hijau, EEGH) influences the hematology system, in this paper, the safety test was done to ensure the safety of its use through subchronic toxicity test of EEGH on the hematology parameters of Wistar rats. The test group consisted of three groups treated with EEGH 100 mg/kg, 200 mg/kg, and 400 mg/kg, while the control group was given by 0.5% CMC-Na, with 8 rats each respectively. By using blood samples taken from orbital sinus on the 29th day, common hematologic parameters (erythrocytes, leukocytes, and hemoglobin level), the parameters of hemostasis (platelets, pT, aPTT, BT) and immune parameters (Differential Leukocytes Counts include neutrophils segment, lymphocytes, monocytes, and eosinophils) were finally observed and showed that the 28 days-addition of EEGH increase the hematological parameters of Wistar rats

    A scientometric analysis and review of fall from height research in construction

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    Fall from height (FFH) in the construction industry has earned much attention among researchers in recent years. The present review-based study introduced a science mapping approach to evaluate the FFH studies related to the construction industry. This study, through an extensive bibliometric and scientometric assessment, recognized the most active journals, keywords and the nations in the field of FFH studies since 2000. Analysis of the authors’ keywords revealed the emerging research topics in the FFH research community. Recent studies have been discovered to pay more attention to the application of Computer and Information Technology (CIT) tools, particularly building information modelling (BIM) in research related to FFH. Other emerging research areas in the domain of FFH include rule checking, and prevention through design. The findings summarized the mainstream research areas (e.g., safety management program), discussed existing research gaps in FFH domain (e.g., the adaptability of safety management system), and suggests future directions in FFH research. The recommended future directions could contribute to improving safety for the FFH research community by evaluating existing fall prevention programs in different contexts; integrating multiple CIT tools in the entire project lifecycle; designing fall safety courses to workers associated with temporary agents and prototype safety knowledge tool development. The current study was restricted to the FFH literature sample included the journal articles published only in English and in Scopus

    Threat assessment algorithm for Active Blind Spot Assist system using short range radar sensor

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    Road safety has become more concern due to the number of accidents that keeps increasing every year. The safety systems include from simple installation such as seat belt, airbag, and rear camera to more complicated and intelligent systems such as braking assist, lane change assist, steering control and blind spot monitoring. This paper proposes another intelligent safety system to be implemented in passenger vehicle by monitoring the blind-spot region by using automotive short range radar as sensor to assess its surrounding. This system is called Active Blind-Spot Assist (ABSA) system and this system will collaborate with a Steering Intervention system for autonomous steering maneuvers. The objective of ABSA system is to deploy safety interventions by giving warning to the driver whenever other vehicle is detected within the blind-spot region. Furthermore, this active system also triggers autonomous steering control when the potential of collision with the detected vehicle increases greatly. Consequently, a threat assessment algorithm is developed to evaluate the right moment to give safety interventions to the driver and the conditions for autonomous steering maneuvers. The process of developing the threat assessment algorithm explained in this paper

    SCAR arrow-wing active flutter suppression system

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    The potential performance and direct operating cost benefits of an active flutter suppression system (FSS) for the NASA arrow-wing supersonic cruise configuration were determined. A FSS designed to increase the flutter speed of the baseline airplane 20 percent. A comparison was made of the performance and direct operating cost between the FSS equipped aircraft and a previously defined configuration with structural modifications to provide the same flutter speed. Control system synthesis and evaluation indicated that a FSS could provide the increase in flutter speed without degrading airplane reliability, safety, handling qualities, or ride quality, and without increasing repeated loads or hydraulic and electrical power capacity requirements

    Study and Analysis 100-car Naturalistic Driving Data

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    poster abstractEvery year, there are a large number of injuries and fatalities caused by vehicles crashes. In particular, pedestrian accidents are often fatal and have greatly impacted people’s lives. Vehicle active safety system can sense and identify potential crash events and prevent or mitigate the collision either by warming the driver or by taking appropriate control actions such as autonomous braking. To design such these kinds of systems, we need to study how accidents happen and to avoid the accident in real-life scenarios. In this research, the Transportation Active Safety Institute (TASI) has recruited 110 drivers to collect naturalist driving data for pedestrian behavior analysis. In this project, my work is first to study how automatic pedestrian detection system works and verifies the detection results. I have worked analyzing picture frames from videos and by identifying pedestrians in these picture frames. Other components that are taken into consideration are the human factors, biomechanics, data acquisition and analysis, and consumer awareness. TASI uses facilities such as car simulators, Drive Safety DS-600c, directed towards the research of the driver’s behaviors and for testing the active safety system. It is the main source for testing the system since it projects a scenario of road images that interacts with a cab of a car to provide an immersive driving experience. Upon completion of the research, there should be a successful safety system for implementing in cars that can effectively reduce vehicle crashes by alarming drivers of different dangers that might appear while driving
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