• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.411-415
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• 2007

The reduction of airborne and structure-borne noise of a shipboard pump for a navel ship is very important because the noise levels of the pump must not exceed criteria such as MIL-STD. In this paper, several practical examples of reducing the noise levels are presented. The examples show that the inadequate rotor-balancing and shaft-alignment results in the increase of the structure-borne noise on all lower mounts. It is also found that the unequal loading on mounts can cause the dramatically increasing the noise levels on certain local positions. Since the piping system arrangement such as valve location, flexible joint, and elbow location affects on the noise measurement, care must be taken to minimize the unnecessary noise from the piping system.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.2
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• pp.70-83
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• 2001

The required standards for environmental tests for communication and electronic equipment used currently in the army are not standards into which the Korean climate and use environment are taken into consideration. But the environmental testing standards of the U.S. army at the time of its establishment(MIL-STD-810) “A” version has been used without taking into consideration the Korean domestic situation and conditions by simply translating the US standards. Adherence to these standards may limit the ability to supply materials in case of emergency since the increase in the manufacturing costs according to excessively strict standards induces an increase in the acquisition cost of military equipment, unnecessarily high maintenance and repair expenses are consumed, and stocks of parts for the military use have to be retained at all times.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.3
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• pp.378-386
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• 2014

In this paper, safety evaluation method simulating battlefield environment was studied to verify military operability of commercial lithium secondary battery. Based on the MIL-STD-2105D and STANAG standards, safety tests of lithium secondary battery module were conducted, such as bullet impact, fragment impact, fast cook-off and slow cook-off. All results satisfied the safety evaluation criteria, founded on military standard. It suggests that the lithium secondary module has high potential to be applied in a military power source. The safety evaluation methods developed in this paper can be valuable to propose the new military standards for commercial lithium secondary batteries.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.518-523
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• 2009

Main source of URN(Underwater Radiated Noise) which is related to the ship's survivability is divided into two groups. Cavitation is main source of URN when the speed of ship is upper than CIS(Cavitation Inception Speed). But when the speed of ship is lower than CIS, main source of URN is structure-borne noise on the hull which is originated from propulsion system, pump system or transmitted vibration of pipe system. In this paper, to reduce the vibration of discharge pipe and valve system, back flow prevent globe valve and new rubber mount are applied to the ship. As the result of applying new valve and mount, the vibration is reduced drastically.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.4 no.2
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• pp.39-44
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• 1998

We used recording device(EDR-3) to monitor the packages and the vehicle during shipment. Provided we did this enough times, we began to gain statistically valid information which could be used to describe the particular channel of distribution. The event was obviously changed from trip to trip, but in general we could have an idea of what to expect. Considerable amount of time and money were invested to record field data. Although not ideal, it was the best suited approach to gain information regarding a specific distribution channel. Based on the recorded field data, we could make our own packaging vibration testing specification through MIL-STD-810D(Guidance for development of laboratory dynamic test specification). This test specification was proved several times through field tests. As a result, we gained confidence in this revised vibration specification and come to know the development procedures of a laboratory dynamic test specification.

• Journal of Korean Society for Quality Management
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• v.24 no.3
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• pp.77-93
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• 1996

This paper is concerned with the International Standard ISO 2859-1 (1989), Sampling Plans Indexed by Acceptable Quality Level (AQL) for Lot-by-Lot Inspection, his standard is AQL type sampling scheme, and incorporates switching rules to move among normal, tightened, and reduced inspections. Sample size code letters and inspection levels of ISO 2859-1 are the same as those of other attributes standards MIL-STD-105D, ANSI Z1.4, and KS A 3109. But ISO 2859-1 has more simple switching rules than KS A 3109 has. The sampling procedures of the ISO 2859-1 are matched to the variables international standard ISO 3951 to enable us to move between them. Composite OC and ASN curves are given for AQL 2.5% and code letter F.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.4
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• pp.630-638
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• 2011

A new smooth bore test barrel was developed to be used in sensitivity assessment test for explosives and fragment impact test. The bore diameter of the barrel is 20 mm, and the powder chamber is designed to be replaceable with the 12.7 mm, 20 mm and 30 mm type chamber. The test results showed the wide range of fragment velocity from 400 to 2000 m/s, included the fragment velocity requirement of the fragment impact test(alternate procedure #1) in MIL-STD-2105B. The stability of the bullet trajectory was checked by test shots and the structural safety of the system has been confirmed through the stress analysis and the interior ballistics analysis of the barrel.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.2
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• pp.299-304
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• 2011

In this paper, we developed the semiconductor neutron radiation detector and the multi-purpose radiation detection technologies for the next generation military personal surveymeter. The PIN type semiconductor neutron detector and the prototype measure the neutron radiation dose upto 1,000cGy with ${\pm}20%$ error. It also have a good performance about the Gamma, Alpha and Beta radiation and MIL-STD-810F.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.1421-1424
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• 2005

저궤도 위성인 다목적실용위성 2호의 컴퓨터 시스템은 3개 프로세서로 구성된 분산처리 구조이며 프로세서와 프로세서, 프로세서와 주변 장치들과의 통신은 MIL-STD-1553B 버스를 통해 이루어진다. 이들 3개 프로세서들 상에서 실행되는 탑재소프트웨어는 위성의 하드웨어 및 주변 입출력 장치들을 제어 및 관리한다. 그리고 위성의 결함을 관리하는 기능과 비상시에는 지상과의 연결 없이 위성을 자동제어 하는 기능들 또한 탑재소프트웨어에 구현되어져있다. 본 논문에서는 저궤도 위성인 다목적실용위성-2호의 임무를 수행하기 위한 탑재소프트웨어의 구성 및 기능, 개발과정과 개발환경을 소개한다.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1950-1952
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• 2002

원자력 발전소 방사성 잡음 규제기준을 설정하기 위하여 발전소 내의 전자파 잡음 환경을 측정하였다. 대상 발전소는 1000 MW급 울진 원자력발전소 3호기로 발전소 출력 0 %에서부터 100 %까지 10일간 주 제어실 및 전기설비실 주변을 대상으로 US NRC Reg. Guide 1.180 및 Mil-Std-462D를 측정기준으로 하여 전기장 10 kHz ${\sim}$ 7 GHz. 자기장 30 Hz ${\sim}$ 100 kHz의 방사성 잡음을 측정하였다. 측정결과를 최소자승법을 이용한 회귀분석으로 잡음 한계값을 유도하여 미국 EPRI 및 NRC 측정결과와 비교한 결과 자기장의 경우 낮은 한계값을 보였고 전기장의 경우는 20 dB 이상 높게 결정되었다.