• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.3 s.18
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• pp.11-20
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• 2004

In this paper, the acceptance criteria(Striking Velocities) for the A12519 weldments have been developed. Dynamic impact simulation of A12519 plate was achieved by using LS-DYNA, and predict the projectile velocity and the crack length. Also, Ballistic impact tests of A12519 plate have been performed, and compared with analysis results. Critical velocities of A12519 plate were acquired respectively, and striking velocities of A12519 weldments were calculated. Present work data will be used by basic data in ballistic impact test for A12519 weldments.

• Journal of Computing Science and Engineering
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• v.3 no.3
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• pp.181-194
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• 2009

Flash memory is increasingly being used in a wide range of storage applications because of its low power consumption, low access latency, small form factor, and high shock resistance. However, the current platforms for flash memory software development do not meet the ever-increasing requirements of flash memory applications. This paper presents three different hardware platforms for flash memory/NVRAM (non-volatile RAM) software development that overcome the limitations of the current platforms. The three platforms target different types of host system and provide various features that facilitate the development and verification of flash memory/NVRAM software. In this paper, we also demonstrate the usefulness of the three platforms by implementing three different types of storage system (one for each platform) based on them.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.175-180
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• 2002

Loading/Unloading(L/UL) mechanism has been considered to be an alternative to contact start-stop(CSS) mechanism which eliminates stiction and wear associated with frequent start and stop process. It has other advantages including increased areal density due to lower flying height, reduced power consumption, and improved shock resistance. In order for L/UL to be Implemented in Near-field recording system properly, dynamics of optical flying head must be understood and optimized. In this paper the dynamic characteristics during loading process is analyzed numerically to investigate the effect of design parameters such as loading speed. slider shape, and initia conditions on the dynamic reponses of flying head..

• Journal of the Korean Ceramic Society
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• v.20 no.3
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• pp.243-249
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• 1983

This study has examined on the effect for the fitting in porcelain body of MgO-SiO system. The mixture was made of correponding in the theoretical composition of enstatite with Kyul Sung Talc and sea water magnesia cake. Hyup Jin Kaolin as clay minerals to give the mixture plasticity was added 10% by weight of the mixture. Feldspar was added inv various kinds of 1%-20% by weight of the above mixture. After the physical properties and microstructures were carefully examined the following results were obtained. 1. The addition amount of feldspar should generally be from 5% to 10% by weight of the mixture to be good for the properties of the strength and the range of the firing temperature. 2. The 5% addition amount of feldspar was good for the apparent bulk density. 3. 5% and 10% additions showed up stably excellant with respect to the various properties Therefore when we considered the apparent bulk density and the thermal shock resistance 5% addition amount of feldspar showed the most excellant properties between $1350^{\circ}C$ and $1400^{\circ}C$.

• The Korean Journal of Zoology
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• v.30 no.3
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• pp.301-310
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• 1987

본 실험에서는 반SP와 thermotolerance 사이에 어떠한 상관관계가 있는지를 알아보기 위하여, 생쥐 SCK 종양세포에서 heat(45$^{\circ}$, 46$^{\circ}C$)처리가 단백질 합성과 세포의 생존에 미치는 영향을 비교하여 보았다. 그 결과 heat 처리를 받은 세포는 HS$\ulcorner$(70K, 87K)를 측이하게 많이 합성했으며, 다음 heat를 받았을 때는 높은 생존율을 꼬였다. 그리고 이러한 thermotolerance가 생성되고 감퇴되는 kinetics는 HSP가 합성되고 감퇴되는 kinetics와 연관성을 보여 주었다. 이러한 결과로 HSP는 heat shock로부터 세포를 보호하는 데 중요한 역할을 할 수 있다고 생 각된다. 아울러, glycerol을 처리하여 HSP의 합성을 봉쇄시켰을 경우에도 열에 대해 저항성을 갖게 되는 실험결과로 미루어, 세포가 갖게 되는 heat resistance에는 (1) HSP의 합성을 초래하지 않는 요인에 의해 유도되는 heatprotection과 (2) 열처리 등의 결과 합성되는 반SP에 의해 유도되는 thermotolerance의 두가지 경우가 있을 것으로 추론할 수 있었다.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.1
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• pp.41-55
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• 2015

This study is proposed a new hybrid mount having a moving-magnet type electromagnetic actuator to reduce the vibration transmitted from naval shipboard equipment to the structure of the ship's hull. Optimal design specifications are determined through experimental analysis. The detailed design of the hybrid mount is determined through several design steps with electromagnetic numerical analysis using Maxwell Software(S/W). The hybrid mount that combines a rubber mount and an electromagnetic actuator has a fail-safe function for shock resistance. The mount is fabricated and tested using a universal testing machine to evaluate the design specifications. Finally, numerical simulation of the hybrid mount is performed to confirm control performance and applicability.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.6
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• pp.810-818
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• 2011

This paper analyzed the suitability about the isolation performance criteria which was based on human impedance and effect of current in IEC 60479-1 on the safety of human being was examined. The method of evaluation by megger and DC voltmeter was analyzed. The differences of isolation performance according to design of high-voltage system were analyzed. The factors which affect the insulation performance were analyzed for HFCV, EV, HEV, etc. through analysis of the isolation performance evaluation method. Finally, design for improved isolation performance was proposed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.28-29
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• 2014

In this study, flexural strength by fiber reinforced for steel fiber and reinforced polyamide fiber concrete, and concrete fracture properties by improvement of flexural toughness and high-velocity projectile impact were evaluated. As a result, it was confirmed that flexural strength are improved by distribution of stress and suppress of cracks, and the back desquamation of concrete by high-velocity projectile impact is suppressed. In addition, It was observed that the spalling of rear is caused when tension stress is caused as shock wave by high-velocity projectile impact was transferred to the rear and tension stress is suppressed by fiber reinforcement.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.42-47
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• 2004

Metallic glasses are amorphous meta-stable solids and are now being processed in bulk form suitable for structural applications including impact. Bulk metallic glasses have many unique mechanical properties such as high yield strength and fracture toughness, good corrosion and wear resistance that distinguish them from crystalline metals and alloys. However, only a few studies could be found mentioning the dynamic response and damage of metallic glasses under impact or shock loading. In this study, we employed a small explosive detonator for the dynamic indentation on a Zr-based bulk amorphous metal in order to evaluate the damage behavior of bulk amorphous metal under impact loading. These results were compared with those of spherical indentation under quasi-static and impact loading. The interface bonded specimens were adopted to observe the appearances of subsurface damage induced during indentation under different loading conditions.

• Proceedings of the Materials Research Society of Korea Conference
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• 1993.05a
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• pp.118-119
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• 1993

Aluminium titanate (Al$_2$TiO$_{5}$) as structural ceramics is known as a low thermal exansion, a low thermal conductivity, a low Young's modulus, and excellent thermal shock resistant material. These properities allow for the testing as an insulating material in engines for portliner, piston bottom an turbo charger. However, those composites has low mechanical strength due to the presence of microcracks developed by the large difference in thermal expansion coefficients along crystallographic directions exceed the internal strength of material and its tendency to decompose into $Al_2$O$_3$ and TiO$_2$ at temperature below 130$0^{\circ}C$ limit however the application of aluminium titanate.e.