• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.573-584
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• 2016

The train control system is a facility to ensure model-based design and safe train operation, and its safety is the most important factor for system introduction, complexity of the design information and traceability etc. Therefore, the model-based design and safety activities regarding the way-side equipment of a train control system is also highlighted. To solve this problem, In this paper, model-based design was carried out first to develop an effective train control system, which is represented by SysML(System Modeling Language). The test scenarios that can take advantage of the design model were created to improve the train safety control system. Case studies of a model-based design of a train-centric train control system were applied to the test scenarios; the results demonstrated its usability. The improved activity over the test highlighted the safety improvement approach, and it is expected to reduce the cost and time in the conceptual design of a future development model-based train control system.

• Nuclear Engineering and Technology
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• v.40 no.3
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• pp.199-212
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• 2008

A small-break loss of coolant accident (SB-LOCA) test with a break size equivalent to a 3-inch cold leg break of the APR1400 was carried out as the first transient integral effect test using the ATLAS (Advanced Thermal-hydraulic Test Loop for Accident Simulation). This was the first integral effect test to investigate the integral performance of the test facility and to verify its simulation capability for one of the design-basis accidents. Reasonably good thermal hydraulic data was obtained so that an integral performance of the fluid sub-systems was identified and control performance of the ATLAS was confirmed under real thermal hydraulic conditions. Based on the measured data, a post-test calculation was carried out using the best-estimate thermal hydraulic safety analysis code, MARS 3.1, and the similarity between the expected and actual data was investigated. On the whole, the post-test calculation reasonably predicts the major thermal hydraulic parameters measured during the SB-LOCA test. The obtained data will be used to enhance the simulation capability of the ATLAS and to improve an input model of the ATLAS for simulation of other target scenarios.

• The KIPS Transactions:PartD
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• v.11D no.4
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• pp.855-864
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• 2004

Programmers can be got the test-related information for implementation without interference of source code complexity by use of the formal specification. Especially the external inputs and system responses can be represented precisely by formal specification in testing phase of web-based software systems. This paper suggests a method of extracting test cases by use of formal specification. Object-Z formal specification represents various test-related information for complex functions of web-based applications. State Transition Models could be built from the formal specification so that test scenarios were extracted from STDs from the highest level to detail levels. The target system for verification of this method is a web-based banking system which is necessary to be secured and critical on errors. This method would be an important factor in automatizing test procedure for web-based application software systems combining the user-base test technique.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.439-442
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• 2005

An airborne radar performance can be sensitive to the variation of the Doppler center frequency and the spectral spread of the ground clutter return due to the radar platform moving and aspect angle of the scanning beam to the target. In this paper, for the performance test of the airborne pulsed Doppler radar system developed, the high-speed radar data acquisition system is implemented for acquiring the raw radar signal in real-time. Based on the various test scenarios from airborne-platform to the moving platform, the various radar target and clutter signals are collected and their spectrum is analyzed for the verification of the radar performance in the real-time flight test environments.

• Smart Structures and Systems
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• v.16 no.6
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• pp.1003-1021
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• 2015

MR dampers have been proposed for the control of cable vibration of cable-stayed bridge in recent years due to their high performance and low energy consumption. However, the highly nonlinear feature of MR dampers makes them difficult to be designed with efficient semi-active control algorithms. Simulation study has previously been carried out on the cable-MR damper system using a semi-active control algorithm derived based on the universal design curve of dampers and a bilinear mechanical model of the MR damper. This paper aims to verify the effectiveness of the MR damper for mitigating cable vibration through a full-scale experimental test, using the same semi-active control strategy as in the simulation study. A long stay cable fabricated for a real bridge was set-up with the MR damper installed. The cable was excited under both free and forced vibrations. Different test scenarios were considered where the MR damper was tuned as passive damper with minimum or maximum input current, or the input current of the damper was changed according to the proposed semi-active control algorithm. The effectiveness of the MR damper for controlling the cable vibration was assessed through computing the damping ratio of the cable for free vibration and the root mean square value of acceleration of the cable for forced vibration.

• Journal of Korean Society for Quality Management
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• v.46 no.3
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• pp.453-464
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• 2018

Purpose: The purpose of this study is to propose a solution to the case where $V_{50}$ calculation is impossible in the process of bulletproof test. Methods: In this study, we proposed a $V_{50}$ estimation method using logistic regression analysis. Six scenarios were applied by combining the homogeneity of the sample and the speed range. Then, 1,000 simulations were performed per scenario and six assumptions reflecting the reality were applied. Results: The result of the study, it was confirmed that there was no statistical difference between the $V_{50}$ value calculated by the conventional method and the $V_{50}$ value calculated by the improvement method. Therefore, in situations where $V_{50}$ can not be calculated, it is reasonable to use logistic regression analysis. Conclusion: This study develops a methodology that is easy to use and reliable by using statistical model based on actual data.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.1
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• pp.6-14
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• 1996

In this paper we present an algorithm to discriminate an underwater target under track against an acoustic counter-measure(ACM) source, based on a sequential hypothesis test. The ACM source is separated from the target under track and generates, while drifting, measurements with false range and Doppler information. The purpose of the ACM is to mislead the target-tracking and to help the true target evade a pursuer. The algorithm uses as a test statistic a function of the innovation sequences from extended Kalman filters to estimate the target dynamics and the drifting position of the ACM source. Numerical experiments on various scenarios show that the proposed algorithm discriminates the target against an ACM source very fast with a high probability of success.

• Journal of Trauma and Injury
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• v.34 no.3
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• pp.212-217
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• 2021

Various medical scenarios have arisen with the prolonged coronavirus disease 2019 (COVID-19) pandemic. In particular, the increasing number of asymptomatic COVID-19 patients has prompted reports of emergency surgical experiences with these patients at regional trauma centers. In this report, we describe an example. A 25-year-old male was admitted to the emergency room after a traffic accident. The patient presented with stuporous mentality, and his vital signs were in the normal range. Lacerations were observed in the left eyebrow area and preauricular area, with hemotympanum in the right ear. Brain computed tomography showed a contusional hemorrhage in the right frontal area and an epidural hematoma in the right temporal area with a compound, comminuted fracture and depressed skull bone. Surgical treatment was planned, and the patient was intubated to prepare for surgery. A blood transfusion was prepared, and a central venous catheter was secured. The initial COVID-19 test administered upon presentation to the emergency room had a positive result, and a confirmatory polymerase chain reaction (PCR) test was administered. The PCR test confirmed a positive result. Emergency surgical treatment was performed because the patient's consciousness gradually deteriorated. The risk of infection was high due to the open and unclean wounds in the skull and brain. We prepared and divided the COVID-19 surgical team, including the patient's transportation team, anesthesia team, and surgical preparation team, for successful surgery without any transmission or morbidity. The patient recovered consciousness after the operation, received close monitoring, and did not show any deterioration due to COVID-19.

• Journal of Auto-vehicle Safety Association
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• v.11 no.1
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• pp.7-16
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• 2019

There are trying to reduce damage from automobile accident in many countries. In many automobile companies, there have been active study on development of ADAS (Advanced Driver Assistance Systems) for commercialization, in order to reduce damage from automobile accident. ADAS is the system providing convenience and safeness for drivers. Generally, ADAS is composed of ACC (Adaptive Cruise Control), LKAS (Lane Keeping Assist System), and AEB (Autonomous Emergency Braking). AEB of the ADAS, it is an autonomous emergency braking system and it senses potential collide and avoids or degrades it. Therefore AEB plays a significant role in reducing automobile accident rate. However, AEB safety evaluation method is not established not yet. For this reason, this study suggests safety evaluation scenarios with adding cut-in, sensor malfunctioning scenario that scenario domestic street conditions considered as well as original standard AEB scenario of Euro NCAP for establishment of safety evaluation method of AEB. And verifying validity of suggested scenario by comparing the calculated values of the theoretical formulas presented in the previous study with results of the actual vehicle test.

• International Journal of Computer Science & Network Security
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• v.21 no.11
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• pp.59-66
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• 2021

Many incidents of Carbon Monoxide (CO) poisoning have occurred because of people being unaware of its presence. There are currently available systems on the market, but they are limited to measuring CO in a certain area and lack vital functions. Additionally, little to no evidence-based information on their quality was available. Thus, a mobile application for detecting CO gas leakage in a vehicle and critical features to assist victims was developed. A usability and functionality test were conducted to determine the product's quality utilizing nine usability and six functionality task scenarios (n=5). Then, a System Usability Scale test was performed to obtain system satisfaction, usability, and learnability (n=50). The usability and functionality test shows that all the tasks given for both tests were 100% successful. The overall score obtained for SUS was 71.4, which indicates good acceptance and usability. Around 20% of respondents claimed that they would need the support of a technical person to be able to use the application and that they needed to learn a lot of things before they could use the application, which indicates the overall high learnability of the application. The result provides empirical evidence that the CO gas leakage detection mobile application is successful and receives good usability, functionality, acceptability, learnability, and satisfaction assessments. DetGas could benefit automobile owners and other stakeholders by mitigating the risk and harm associated with gas leaking that exceeds the safe limit.