• Title/Summary/Keyword: Crash performance

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Achievements of Nursing Students among Simulation and Traditional Education of Bleeding Patients (출혈환자 간호 시뮬레이션 실습에 따른 간호학생의 학업성취)

  • Choi, Eun Hee;Kwon, Kyung Nam;Lee, Eun Ju
    • The Journal of Korean Academic Society of Nursing Education
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    • v.19 no.1
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    • pp.52-59
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    • 2013
  • Purpose: This study was performed to identify in nursing students the effects of simulation practice for hemorrhagic patients. Methods: Subjects were sophomore nursing students in Daegu (n=133). A self describing performance questionnaire which included knowledge, skill and attitude towards bleeding patients was given. Consent was received from students. The data was analyzed by ANOVA with Scheffe's test and Mann-Whitney U test using the SPSS 12.0 Program. Result: Subjective and objective knowledge and skill showed significant improvement in the control group, especially in assessment, correct medication administration, explaination of NPO and preparing the crash cart for a cardiac arrest. Objective knowledge and skill was significantly higher in the control group although attitude was not. Conclusion: Simulation practice was an effective education method for improving knowledge, skill and attitude in nursing students.

Reduction of Structure-borne Idle Noise with the Insertion of a Composite Body inside Vehicle Body Skeleton (차체골격내 복합체 삽입을 이용한 구조기인 아이들 소음저감)

  • Kim, Hyo-Sig;Kim, Joong-Hee
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.22 no.4
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    • pp.335-343
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    • 2012
  • As a matter of fact, it has been not allowed to modify the shape of a vehicle body skeleton since the technical definition for the structure was fixed and the corresponding molds were developed. By the way, if it is available to apply an alternative to reinforce the skeleton without changing its mold, it must be much flexible to improve the performance qualities relevant to not only NVH(noise, vibration and harshness) but also crash and durability. Recently, a solution of so-called composite body becomes available for the need. We present a design method to insert the composite body inside a vehicle body skeleton in order to improve a structure-borne noise at the idle condition. The algorithms, topology optimization and design sensitivity analysis, are applied to mainly search the sensitive structural sections in the body skeleton and to extract the target stiffness of the sections. Inserting the composite bodies into the sensitive portions, it is predicted to achieve the countermeasures which can compromize the design availability in terms of the idle noise and weight. According to the validation result with test vehicles, the concerned noise transfer function is reduced and the idle booming noise is resultantly improved.

Computing and Reducing Transient Error Propagation in Registers

  • Yan, Jun;Zhang, Wei
    • Journal of Computing Science and Engineering
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    • v.5 no.2
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    • pp.121-130
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    • 2011
  • Recent research indicates that transient errors will increasingly become a critical concern in microprocessor design. As embedded processors are widely used in reliability-critical or noisy environments, it is necessary to develop cost-effective fault-tolerant techniques to protect processors against transient errors. The register file is one of the critical components that can significantly affect microprocessor system reliability, since registers are typically accessed very frequently, and transient errors in registers can be easily propagated to functional units or the memory system, leading to silent data error (SDC) or system crash. This paper focuses on investigating the impact of register file soft errors on system reliability and developing cost-effective techniques to improve the register file immunity to soft errors. This paper proposes the register vulnerability factor (RVF) concept to characterize the probability that register transient errors can escape the register file and thus potentially affect system reliability. We propose an approach to compute the RVF based on register access patterns. In this paper, we also propose two compiler-directed techniques and a hybrid approach to improve register file reliability cost-effectively by lowering the RVF value. Our experiments indicate that on average, RVF can be reduced to 9.1% and 9.5% by the hyperblock-based instruction re-scheduling and the reliability-oriented register assignment respectively, which can potentially lower the reliability cost significantly, without sacrificing the register value integrity.

A Study on Low-Overhead Collision Warning Scheme using Vehicle-to-Vehicle Communications (차량 간 통신을 이용한 저비용 사고 위험 방지 기술에 관한 연구)

  • Lee, Ji-Hoon;Kim, Dae-Youb
    • Journal of Korea Multimedia Society
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    • v.15 no.10
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    • pp.1221-1227
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    • 2012
  • It is expected that the vehicle safety systems using vehicle-to-vehicle communication can reduce the possibility of vehicle collision and prevent the chain crash by promptly delivering the status of neighboring vehicles. Many IEEE 802.11 DCF based Flooding schemes have been proposed, but they may generally expose the problems that the transmission efficiency is sharply declined as the vehicle density has increased and then is related to the low possibility of the channel access. Therefore, this paper proposes a collision prevention scheme using adaptively controlling the frequency of the message exchanges based on the current status of neighboring vehicles. Moreover, it is shown from simulation that the proposed scheme provides the performance gains over the existing Flooding based scheme.

Analytical study of failure damage to 270,000-kL LNG storage tank under blast loading

  • Lee, Sang Won;Choi, Seung Jai;Kim, Jang-Ho Jay
    • Computers and Concrete
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    • v.17 no.2
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    • pp.201-214
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    • 2016
  • The outer tank of a liquefied natural gas (LNG) storage tank is a longitudinally and meridianally pre-stressed concrete (PSC) wall structure. Because of the current trend of constructing larger LNG storage tanks, the pre-stressing forces required to increase wall strength must be significantly increased. Because of the increase in tank sizes and pre-stressing forces, an extreme loading scenario such as a bomb blast or an airplane crash needs to be investigated. Therefore, in this study, the blast resistance performance of LNG storage tanks was analyzed by conducting a blast simulation to investigate the safety of larger LNG storage tanks. Test data validation for a blast simulation of reinforced concrete panels was performed using a specific FEM code, LS-DYNA, prior to a full-scale blast simulation of the outer tank of a 270,000-kL LNG storage tank. Another objective of this study was to evaluate the safety and serviceability of an LNG storage tank with respect to varying amounts of explosive charge. The results of this study can be used as basic data for the design and safety evaluation of PSC LNG storage tanks.

The Types of Road Weather Big Data and the Strategy for Their Use: Case Analysis (도로 기상 빅데이터 유형별 활용 전략: 국내외 사례 분석)

  • Hahm, Yukun;Jun, YongJoo;Kim, KangHwa;Kim, Seunghyun
    • The Journal of Bigdata
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    • v.2 no.2
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    • pp.129-140
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    • 2017
  • Weather acts through low visibility, precipitation, high winds, and temperature extremes to affect driver capabilities, vehicle performance (i.e., traction, stability and maneuverability), pavement friction, roadway infrastructure, crash risk, traffic flow, and agency productivity. Recently a variety of road weather big data sources such as CCTV, road sensor/systems, car sensor have been developed to solve the weather-related problems, This study identifies and defines the types and characteristics of these sources to suggest how to utilize them for car safety and efficiency as well as road management through analyzing domestic and oversea cases of road weather big data applications.

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Implementation of Timing Synchronization in Vehicle Communication System

  • Lee, Sang-Yub;Lee, Chul-Dong;Kwak, Jae-Min
    • Journal of information and communication convergence engineering
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    • v.8 no.3
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    • pp.289-294
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    • 2010
  • In the vehicle communication system, transferred information is needed to be detected as possible as fast in order to inform car status located in front and rear side. Through the moving vehicle information, we can avoid the crash caused by sudden break of front one or acquire to real time traffic data to check the detour road. To be connecting the wireless communication between the vehicles, fast timing synchronization can be a key factor. Finding out the sync point fast is able to have more marginal time to compensate the distorted signals caused by channel variance. Thus, we introduce the combination method which helps find out the start of frame quickly. It is executed by auto-correlation and cross-correlation simultaneously using only short preambles. With taking the absolute value at the implemented synch block output, the proposed method shows much better system performance to us.

The study on Topology Optimization for Crashworthiness enhancement in Protective shell frame of Rolling Stock leading-cab (철도 차량 전두부 충돌 피해 저감을 위한 Protective shell frame의 위상 최적화에 관한 연구)

  • Kim, Hyun-Jun;Kim, Se-Hoon;Jung, Hyun-Seung;Kwon, Tae-Su;Suh, Myung-Won
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.138-143
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    • 2007
  • The leading-cab (high energy absorption area) of rolling stock directly is impacted on the frontal crash unlike other cabs. Thus, leading-cab has a structurally complex shape to solve getting concentrated loads. However, in order to enhance structural performance and to achieve the weight reduction of cab, changing the sizes and adjusting the distance of members do not take an effective result. Therefore, in design phase, to find the material arrangement which helps structural capacity be better should be done. This research applies the topology optimization to concept design of protective shell frame on strategy of crush energy absorption with considering pressure and vertical loads acting on the principal part of leading-cab. In this research, topology optimization method focuses on structural design, and which yields optimal material arrangement under given loads and boundary conditions using density method which has the density of material as design variables. Finally, this research presents optimal material arrangement and structure of protective shell frame on given loads with applying topology optimization.

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A Study on Implementation of a Real-Time Control Algorithm for Ship Main Engine Remote Control Systems (선박 주기관 원격제어시스템을 위한 실시간 제어알고리즘 구현에 관한 연구)

  • 김종화
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.6
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    • pp.901-907
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    • 1998
  • This paper presents a real-time control technique for the development of a ship main engine remote control system, In general several tasks are executed by the event-driven method in real-time system. However when some tasks have time delay components it is difficult to achieve good real-time performance. To cope with this problem a number of timers in most conventional system have been used. In this paper we introduce a real-time control methodology of dealing effectively with tasks including time delay components using one hardware timer. And also a speed control method of main engine which includes critical revolution range a crash astern and a emergency ahead function a switching method of remote control position and a flickering method for the indication of multi-stage alarm are discussed. As long as functions and method are imple-mented as forms of tasks the development of main engine remote control systems can be easy for different types of engines.

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Crashworthy Design and Test of Landing Gear (착륙장치 내추락 설계 및 시험평가)

  • Kim, Tae-Uk;Lee, Sang-Wook;Shin, Jeong-Woo;Lee, Seung-Kyu;Kim, Sung-Chan;Hwang, In-Hee;Jo, Jeong-Jun;Lee, Je-Dong
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.7
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    • pp.601-607
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    • 2012
  • The main function of a landing gear is to absorb the impact energy during touchdown. It it occasionally required for landing gear to have crashworthiness for improving survivability and safety in case of emergency landing. This paper introduces the design concept, performance analysis and drop test procedures for the development of the crashworthy landing gear. The shock absorbing ability and the crash behavior are proved by analyzing various sensor data and video clips from high speed camera recording during drop tests.