• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.4
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• pp.299-305
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• 2015

A statistical annoyance model to railway noise at platform was proposed by jury evaluation test performed in hearing laboratory. ITX-Saemaeul and Mugunghwa were chosen as the noise sources of the test, and announcement sound was included to simulate real situation. Logistic regression analysis produced %HA_LAB curve. Hosmer-Lemeshow test and classification accuracy test were used to verify the model's statistical significance. It was shown that the model which was generated from relatively small number of samples is statistically significant.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.10
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• pp.948-956
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• 2007

It is important during FSD(Full Scale Development) period to verify whether the aircraft system function meets the aircraft requirements and functional performance. Especially, the functionality of the integrated propulsion system should be verified to evaluate the compatibility with aircraft. Various flight tests such as the engine airstart test, the engine horsepower extraction test, the backup throttle functionality test had been performed to evaluate the engine/aircraft compatibility with T-50 during FSD period. Through such flight tests, it was confirmed that the propulsion system of T-50 was properly designed and installed to the aircraft. This paper shows description on each flight test item, test procedure and test results. It is expected that this paper could be a reference for preparing the propulsion flight test in other aircraft developments.

• Journal of Korean Orthopaedic Sports Medicine
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• v.9 no.2
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• pp.104-108
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• 2010

Purpose: To evaluate the correlation between Korean Shoulder Scoring System and Isokinetic muscle strength test for allowance of the return to unrestricted activities after rotator cuff disease treatment. Materials and Methods: This study examined 59 patients with impingement syndrome and 36 patients with rotator cuff tear. KSS and isokinetic muscle strength were analyzed and we sought to evaluate the correlation between total score or each functional parameter scores of KSS and isokinetic muscle strength deficit with Pearson's correlation test. Results: We found a weak negative correlation between and the total KSS score and the endurance test as well (r<0.346). The correlation between the manual muscle test of KSS and isokinetic strength deficits was not significant (p>0.05). Conclusion: The isokinetic muscle strength deficit had a weak correlarion between total score or the edurance test of KSS. Our results suggest that the Isokinetic muscle strength test may be needed for return to normal activity after treatment.

• Journal of the Korean Society for Railway
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• v.13 no.4
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• pp.363-370
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• 2010

This paper describes the evaluation of structural integrity and dynamic characteristic of inertial load test equipments for performance test of railway vehicle propulsion control system. The propulsion control system of railway vehicle has to be confirmed of safety and reliability prior to its application. Therefore, inertial load test equipments were designed through theoretical equation for performance test of propulsion control system. The structural analysis of inertial load test equipments was conducted using Ansys v11.0 and the dynamic characteristic was evaluated using Adams. The results showed that the structural integrity of inertial load test equipment was satisfied with a safety factor of 10.2 on the bearing part under combined load. Also, the structural stability of flywheel according to dynamic simulation was secured by the maximum oscillation displacement within 0.83mm.

• The KIPS Transactions:PartA
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• v.16A no.4
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• pp.245-254
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• 2009

With the increasing adoption of embedded processors, the need of developing compilers for the embedded processors with timely manner is also growing. Retargeting has been adopted as a viable approach to constructing new compilers by modifying the back-end of an existing compiler. This paper proposes a test suite generation system for testing retargetable C compilers. The proposed system generates the test suite using the grammar coverage concept. Generally, the size of the test suite satisfying the grammar coverage of the source language is very large. Hence, the proposed system also provides the facility to reduce the size of the test suite. According to the experimental result, the reduced test suite can detect 75% of the compiler faults detected by the original test suite though the size of the reduced test suite is only 10% of that of the original test suite in average. This result indicates that the reduction technique proposed in this paper can be effectively used in the prior phase of the development procedure of the embedded compilers.

• Journal of Advanced Navigation Technology
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• v.22 no.4
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• pp.311-318
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• 2018

In this paper, test-bed for the evaluation of wireless communication system on a small launch vehicle is proposed. The proposed test-bed consists of antenna test-coupler, RF attenuators, and RF switch modules. The antenna test-coupler isolates antennas for each band and transmits / receives wireless signals. The RF attenuator and switch are used for path selection of testing signal path. In design and measurement result of the antenna test-coupler, the antenna test-coupler has shielding effect higher than 39.3, 47.1, 56.1 dB at UHF-, S-, X-band. Through testing on small launch vehicle wireless communication system, we were able to successfully transmit and receive data between each test system and launch vehicle with antenna path switching.

• Fire Science and Engineering
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• v.30 no.3
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• pp.55-61
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• 2016

In this study, to determine whether it is possible to apply Polyethylene (PE) compound pipe, which was developed to solve the problem caused by the corrosion of the fire protection piping currently in usein water based fire extinguishing systems, we performed an actual mockup fire test. Since no test standard was available related to the developed compound pipe, we compared and analyzed domestic and international technical materials and test standards and selected suitable fire test standards to evaluate the performance of the PE compound pipe. we applied two fire test standards to the PE compound pipe, viz. those for CPVC and metallic pipes, and conducted a total of 6 experiments to evaluate its performance. According to the results of the first and second fire tests based on the test standard for the CPVC pipe, neither the fitting nor the piping was damaged or deformed and no leakage was observed in the pressure test, which was performed for 5 minutes. For the fire test based on the metallic pipe test standard, a total of 4 experiments were conducted. The first two experiments were conducted to simulate the wet piping system. In the results of this fire test, neither leakage nor rupture was observed from the PE compound pipe and no damage was caused, such as the secession of the PE material. However, in the next two experiments, which simulated the dry system, the PE compound pipe suffered damage and rupture, including deformation before the fire fighting water was discharged. Therefore, we found that the piping performance of the PE compound pipe did not undergo any deterioration, including fusion, deformation, or damage, in the wet piping system simulated fire test.

• Journal of Positioning, Navigation, and Timing
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• v.5 no.4
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• pp.165-172
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• 2016

A Global Navigation Satellite System (GNSS), which is typically exemplified by the Global Positioning System (GPS), employs a open signal structure so it is vulnerable to spoofing electronic attack using a similar malicious signal with that used in the GPS. It is necessary to require a spoofing test evaluation environment to check the risk of spoofing attack and evaluate the performance of a newly developed anti-spoofing technique against spoofing attacks. The present paper proposed a simulation method of spoofing environment based on simulator that can be implementable in a test room and analyzed the spoofing simulation performance using commercial GPS receivers. The implemented spoofing simulation system ran synchronized two GPS simulator modules in a single scenario to generate both of spoofing and GPS signals simultaneously. Because the signals are generated in radio frequency, a commercial GPS receiver can be tested using this system. Experimental test shows the availability of this system, and anti-spoofing performance of a commercial GPS receiver has been analyzed.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.5
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• pp.485-493
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• 2020

Numerical analyses were performed using a one-dimensional Euler equation and Godunov Harten-Lax-Van Leer(HLL) Riemann solver in order to study the deceleration characteristics of a 155 mm projectile in a soft recovery system. The soft recovery system consisting of a series of pressure tubes is a system that decelerates the test projectile fired at supersonic speed using a high-pressure gas and filled water inside. Therefore, depending on the gas pressure and the amount of water filling, the deceleration and the exit velocity of the test projectile inside the pressure tube are determined. In this paper, the deceleration characteristics of the test projectile were analyzed according to the gas pressure and water mass filled.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.2202-2203
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• 2011

AC substation of urban transit supplies a suitable AC power on electricity vehicles. AC substation is verified electrical safety of system through pre-operation inspection on electrical installations to be supplied power from KEPCO. However, because test items and method for AC traction system are unprepared on pre-operation inspection, the general safety and performance verification of AC traction system are very insufficient. Therefore this paper analyze the test examples such as factory equipment tests, factory combined tests and railway tests for the safety and performance verification of AC traction system and present a suitable test items and test standard in domestic.