• Journal of Biomedical Engineering Research
• /
• v.19 no.6
• /
• pp.603-609
• /
• 1998

To anlyze the diffuse axonal injury of the human brain, 3-D finite element models of the adult, two and three years child were developed. Triangular type acceleration which had its maximum value 200g was applied to investigate the effects of acceleration direction and duration time. The pattern of high shear stress generated at the brain stem, pones and midbrain was similar to the pattern of DAI seen in the clinical observation, especially high maximum shear stress was detected in the brain stem of the six year old child model under flexional acceleration. As the duration of acceleration increased generated pressure and maximum shear stress also increased. For the children's model relatively small pressure was generated regardless of the acceleration direction and continued much longer compared with adult's model. From this analysis maximum shear stress was revealed more proper indicator to predict DAI compared to HIC in case of angular acceleration loading.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.48 no.6
• /
• pp.63-70
• /
• 2011

A bicycle is different from vehicles in the structure that a rider is fully exposed to the surrounding environment. Therefore, it needs to make use of prior information about local weather, air quality, trail road condition. Moreover, since it depends on human power for moving, it should acquire route property such as hill slope, winding, and road surface to improve its efficiency in everyday use. Recent mobile applications which are to be used during bicycle riding let us aware of the necessity of development of intelligent bicycles. This study aims to develop a riding state (up-hill, down-hill, accelerating, braking) recognition algorithm using a low-power wrist watch type embedded system which has 3-axis accelerometer and wireless communication capability. The developed algorithm was applied to 19 experimental riding data and showed more than 95% of correct recognition over 83.3% of the total dataset. The altitude and temperature sensor also in the embedded system mounted on the bicycle is being used to improve the accuracy of the algorithm. The developed riding state recognition algorithm is expected to be a platform technology for intelligent bicycle interface system.

• Journal of Korean Society of Transportation
• /
• v.21 no.4
• /
• pp.91-101
• /
• 2003

This study modeled 4-lane highway in three-dimensional virtual reality in order to overcome difficulties of field experiment. and the research subject was placed in a driving simulator. We survey the driver's cognitive characteristics to the alignment changes in the three-dimensional virtual reality highway. Especially, maximizing the identity of driving movements and virtual scenery on the basis of the data obtained by dynamic analysis module. we minimized simulator sickness for the graphic module of driving simulator. And we carried out cognitive evaluation on the basis of adjective words extracted by dictionary and the opinion of specialist. In this study LISREL model was used to detect the causal relation between geometry and safety in cognitive side, and found that geometric change affects the safety of drivers by static and dynamic road safety model in three-dimensional combined alignments. As the result, for constructing safety road. we consider drivers' cognitive characteristics as human factors in road design, and we think that they are very important factors to improve road safety.

• Journal of Korea Technology Innovation Society
• /
• v.20 no.4
• /
• pp.1036-1056
• /
• 2017

The rapid increase of ageing population and chronic disease patients cause high medical expenses, and it led an increased attention to digital healthcare. Smart car technologies for healthcare have been developing to recognize drivers' status and predict diverse driving environments. The present study aimed to understand the research trends of autonomous vehicle technologies of Korea and the United States through time series analysis, network analysis, visualization, and comparison between the two countries. The results suggest that cooperative study needs to be done in common research areas such as driver's safety and algorithms. It is also needed to conduct studies and benchmark about liking technique related to part-to-part and vehicle-to-vehicle as America's competitive advantaged area. In the US, diverse approaches of autonomous vehicle technologies have used to consider the characteristics of various age groups and passengers' health status through sensor, while in Korea, only one aspect, older drivers, is mentioned. Implications for the development direction of autonomous vehicle technologies with competitiveness in considering public health, ethics, and driver's safety and convenience are discussed in detail.

• International Journal of Highway Engineering
• /
• v.7 no.4 s.26
• /
• pp.185-202
• /
• 2005

In this research, to get over restrictions of a field expreiment, we modeled a planning road through the 3D Virtual Reality and achieved data about dynamic response related to sector fluctuation and about driver's visual behavior on testers' driving the Driving Simulator Car with Eye Camera. We made constant efforts to reduce the non-reality and side effect of Driving Simulator on maximizing the accord between motion reproduction and virtual reality based on data Driving Simulator's graphic module achieved by dynamic analysis module. Moreover, we achieved data of driver's natural visual behavior using Eye Camera(FaceLAB) that is able to make an expriment without such attaching equipments such as a helmet and lense. In this paper, to evaluate the level of road's safety, we grasp the meaning of the fluctuation of safety that drivers feel according to change of road geometric structure with methods of Driving Simulator and Eye Camera and investigate the relationship between road geometric structure and safety level. Through this process, we suggest the method to evaluate the road making drivers comfortable and pleasant from planning schemes.

• 재활복지
• /
• v.17 no.4
• /
• pp.339-370
• /
• 2013

This study is to suggest necessary improvements of inconvenient elements as well as the ergonomic design standard to develop disabled cars by evaluating the types of needs and observing the behavior characteristics on their car use and the survey on the complaints of the disabled drivers and their guardians in the use of disabled car. The results of this study are as follows. First, both the disabled drivers and their guardians are found to feel high inconvenience and low satisfaction with the cars they use now. Second, the disabled owner-drivers also answered in a same way as guardians. They find the most difficulty in moving the supporting equipment to get into and out of a car. Both the owner-drivers with disabilities and guardians complained of lack of handiness they face when they wear the seat belts and sitting on the seats. In view of this, a disabled car to be developed should have ergonomic design for its seats and the safety of the seatbelt as well as trouble-free supporting equipment helping them move. Third, rather than owner-drivers with handicaps, guardians expressed more difficulties and less contentment with the cars for the disabled, which is reckoned to lead to the changes of perspectives on development of cars for the disabled breaking away from existing viewpoints focusing on the accessibility to the vehicles. Fourth, both owner-drivers and guardians showed higher interests in driving and other safety and convenience measures than in using supporting equipment to get into and out of vehicles, implying that rather than the accessibility to get into and out of a car, convenience should primarily be taken into account for the design of the disabled car. Fifth, the auto-manufacturer is to give prior thought to user convenience when developing a car in practice. For this, the developer may have the disabled car users join the process of development as well as asking experts for help and participation.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.46 no.1
• /
• pp.18-31
• /
• 2018

Rotorcrafts have more severe crashworthiness conditions than fixed wing aircraft owing to VTOL and hovering. Recently, with the increasing demand for highly efficient transportation system, application of composite materials to aircraft structures is increasing. However, due to the characteristics of composite materials that are susceptible to impact and crash, demand to prove the crashworthiness of composite structures is also increasing. The purpose of present study is to derive the structural concept of composite subfloor for rotorcrafts and verify it. In order to design a crashworthy composite subfloor, the conceptual design of the testbed helicopter for the demonstration and the derivation of energy absorbing requirement were carried out, and the composite energy absorber was designed and verified. Finally, the testbed for the demonstration of a crashworthy composite structure was fabricated, and performed free drop test. It was confirmed that the test results meet the criteria for ensuring occupant survivability.

• Convergence Security Journal
• /
• v.22 no.4
• /
• pp.161-168
• /
• 2022

After the corona virus, as non-face-to-face services are activated, domain services that guarantee integrity by embedding sensing information of the Internet of Things (IoT) with block chain technology are expanding. For example, in areas such as safety and security using CCTV, a process is required to safely update firmware in real time and to confirm that there is no malicious intrusion. In the existing safe security processing procedures, in many cases, the person in charge performing official duties carried a USB device and directly updated the firmware. However, when private blockchain technology such as Hyperledger is used, the convenience and work efficiency of the Internet of Things environment can be expected to increase. This article describes scenarios in how to prevent vulnerabilities in the operating environment of various customers such as firmware updates and device changes in a non-face-to-face environment. In particular, we introduced the optimal blockchain technique for the Internet of Things (IoT), which is easily exposed to malicious security risks such as hacking and information leakage. In this article, we tried to present the necessity and implications of security management that guarantees integrity through operation applying block chain technology in the increasingly expanding Internet of Things environment. If this is used, it is expected to gain insight into how to apply the blockchain technique to guidelines for strengthening the security of the IoT environment in the future.

• Composites Research
• /
• v.36 no.1
• /
• pp.59-67
• /
• 2023

Damage caused by impact on a vehicle composed of CFRP(carbon fiber reinforced plastic) composite to reduce weight in the aerospace industries is related to the safety of passengers. Therefore, it is important to understand the damage behavior of materials that is invisible in impact situations, and research through the FEM(finite element model) is needed to simulate this. In this study, FEM suitable for predicting damage behavior was constructed for impact analysis of unidirectional laminated composite. The calibration parameters of the MAT_54 Enhanced Composite Damage material model in LS-DYNA were acquired by inverse estimation through ANN(artificial neural network) model. The reliability was verified by comparing the result of experiment with the results of the ANN model for the obtained parameter. It was confirmed that accuracy of FEM can be improved through optimization of calibration parameters.

• The Korean Journal of Air & Space Law and Policy
• /
• v.31 no.1
• /
• pp.63-97
• /
• 2016

Ago the passenger who using a wheelchair was denied boarding from the airline. The ACT ON THE PROHIBITION OF DISCRIMINATION AGAINST DISABLED PERSONS prohibits discriminatory treatment of persons with disabilities in transportation. But there are situations that limits the movement on persons with reduced mobility. The international community promote to protect disabled persons and persons with reduced mobility against discrimination and to provide them with assistance when travelling by air. According to news report, the governing Council of the International Civil Aviation Organization (ICAO) has established new global core principles on air transport consumer protection. The principles cover three phases of a customer's experience: before, during and after travel, and will now be considered by ICAO's 191 Member States when they develop or review their applicable national regimes. The international community are recognizing that passengers can benefit from a competitive air transport sector, which offers more choice in fare-service trade-offs and which may encourage carriers to improve their offerings, passengers, including those with disabilities, can also benefit from consumer protection regimes. In accordance with these we will also be provided to regulations that can prevent and protect the air passenger. In this paper analyze the regulations of the international air passenger rights, point out the lack of policy.