• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.961-964
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• 2002

A KS draft of the measurement of sound insulation in buildings and of building elements using sound intensity: laboratory conditions is proposed. It is based on ISO 15186-1. In order to make it as a KS, some contents are carefully tested.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.1138-1141
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• 2002

In this study, the ISO 15186-1 “Measurement of sound insulation in buildings and of building elements using sound intensity - Part 1 : Laboratory conditions” was reviewed in order to make it as a new Korean Industrial Standard. Several main contents are discussed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.845-850
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• 2003

Noise caused by water installations may lead to annoyance in adjacent rooms, for example in dwellings. hospitals and hotels. This part of standard describes a method of measurement allowing comparable results to be obtained in laboratory measurements. The test conditions described herein constitute the standard reference conditions essential for comparisons between laboratories.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1593-1594
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• 2007

모든 장비의 내구성 및 성능 테스트에 있어서 주위 환경 또는 실험 조건 내의 온도 및 습도의 변화는 절대적으로 필요하다. 실용화를 위한 모든 제품은 극한의 상황에서의 테스트가 필수적이며 이를 위한 온도 및 습도 변화가 중요한 변수로 작용한다. 따라서 자동화를 위해서는 항온 항습 컨트롤러를 PC에서의 제어 및 모니터링이 절실하게 요구된다. 본 연구에서는 LabVIEW에 의한 RS-232C 통신 방법을 이용하여 항온 항습 컨트롤 프로그램을 개발하였다.

• ETRI Journal
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• v.36 no.2
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• pp.188-196
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• 2014

This paper describes a simple delay diversity technique for terrestrial digital multimedia broadcasting (T-DMB) and digital audio broadcasting in a single-frequency network (SFN). For the diversity technique, a delay diversity scheme is adopted. In the delay diversity scheme, a non-delayed signal is transmitted in the first antenna, and delayed versions of the signal are transmitted in each additional antenna. For an SFN environment with multiple transmitters, delay diversity can be executed by controlling the emission times of the transmitters. This SFN delay diversity scheme does not require any hardware changes in either the transmitter or receiver, and perfect backward compatibility can be acquired. To evaluate the performance improvement, laboratory tests are executed with various types of commercial T-DMB receivers as well as a measurement receiver. The improvement in the bit error rate performance is evaluated using a measurement receiver, and an improvement of the threshold of visibility value is evaluated for commercial receivers. Test results show that the T-DMB system can obtain diversity gain using the described technique.

• The Korean Journal of Nuclear Medicine
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• v.29 no.3
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• pp.350-354
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• 1995

한국 원자력 연구소 부설 원자력병원에 설치된 AVF 싸이클로트론을 이용하여 요즈음 핵의학에 널리 사용되는 PET 용 싸이클로트론의 에너지를 검정 할 수 있고 양성자 과잉 핵종인 싸이클로트론 동위원소의 생산 수율에 중요한 변수인 양성자에너지를 탄소에 입사시켜 입사빔의 Range와 에너지를 측정하는 방법을 제시하였다. 본 실험에서 사용된 양성자 빔의 양성자 에너지는 35 MeV와 50 MeV 사이였으며, 탄소 막은 두께 6.3mm, 밀도 $1.712 g/cm^3$를 사용하였다. 탄소 표적물을 $0.9^{\circ}$씩 스텝 모터를 사용하여 회전시킴으로 두께를 변화 시켜 공칭 에너지에 대한 Range를 측정함으로써 입사된 양성자의 에너지를 구하였고 이를 인출반경과 RF주파수를 바탕으로 상대론 적으로 계산된 에너지와 비교하였다.

• Smart Structures and Systems
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• v.32 no.2
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• pp.101-109
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• 2023

In order to improve the measurement accuracy of the 6-dimensional accelerometer, the cross coupling compensation method of the accelerometer needs to be studied. In this paper, the non-linear error caused by cross coupling of piezoelectric six-dimensional accelerometer is compensated online. The cross coupling filter is obtained by analyzing the cross coupling principle of a piezoelectric six-dimensional accelerometer. Linear and non-linear fitting methods are designed. A two-level calibration hybrid compensation algorithm is proposed. An experimental prototype of a piezoelectric six-dimensional accelerometer is fabricated. Calibration and test experiments of accelerometer were carried out. The measured results show that the average non-linearity of the proposed algorithm is 2.2628% lower than that of the least square method, the solution time is 0.019382 seconds, and the proposed algorithm can realize the real-time measurement in six dimensions while improving the measurement accuracy. The proposed algorithm combines real-time and high precision. The research results provide theoretical and technical support for the calibration method and online compensation technology of the 6-dimensional accelerometer.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.1
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• pp.35-44
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• 2014

Sound pressure levels in the receiving room while testing airborne sound insulation performance are varied by the measuring points. This may increase the measurement error, then decrease the measurement reliability. With this reason the research has carried out on the method to reduce deviations of sound pressure level in the ISO type rectangular laboratory focusing on the measurement of airborne sound insulation performance. Tests were made to see the effect of sound absorption in the receiving room, loudspeaker locations, microphones locations and flanking transmission path. Consequently, it was resulted that sound absorption in the receiving room and the loudspeaker location have influence on the sound level deviations especially in the low frequency. The microphone location was very important to get measurement reliability. The effective measuring point, which the sound level difference with average sound pressure level is within 2 dB, could yield most reliable average sound pressure level. Therefore it is necessary to find the effective measuring points in the receiving room. Flanking transmission path should be sealed using sound absorber or magnet etc. to prevent from lowering the sound insulation performance.

• Journal of the Korean Solar Energy Society
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• v.31 no.2
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• pp.63-71
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• 2011

The remote-sensng campaign was performed at the Pohang Accelerator Laboratory where is located in a basin 6km inland from Yeongil Bay. The campaign aimed uncertainty assessment of Remtech PA0 SODAR through a mutual comparison with WindCube LIDAR, the remote-sensing equipment for wind resource assessment. The joint observation was carried out by changing the setup for measurement heights three times over two months. The LIDAR measurement was assumed as the reference and the uncertainty of SODAR measurement was quantitatively assessed. Compared with LIDAR, the data availability of SODAR was about half. The wind speed measurement was fitted to a slope of 0.94 and $R^2$ of 0.79 to the LIDAR measurement. However, the relative standard deviation was about 17% under 150m above ground level. Therefore, the Remtech PA0 SODAR is judged to be unsuitable for the evaluation of wind resource assessment and wind turbine performance test, which require accuracy of measurement.

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.5
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• pp.503-510
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• 2021

This paper presents a system that measures the acceleration of the shock caused by the explosion of the precursor warhead for the tandem projectile. The proposed system, which is implemented based on the MIL-STD-810G, Method 517.1, consists of a miniaturized shock measurement device, a cable, accelerometers, and a trigger circuit. The shock measurement device has a size of ¢102 × 171 mm and cable has a length of 3 m. The operational confirmation test is conducted by implementing the measurement system. The Analysis of shock data(accelerometer output data) is carried out using Shock Response Spectrum(SRS), pseudo velocity and plot of acceleration time transient. Through measurement analysis, one can predict the damage of electronics in projectile when precursor warhead is exploded.