• Explosives and Blasting
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• v.27 no.1
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• pp.53-61
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• 2009

R.O.K's explosive manufacturing source was first black powder (B.P) introduced into Korea Dynasty from China. In 1890, black powder was first used for mining blasting in Masan. Nowadays, a vibration control blasting method using the emulsion explosive has been applid to explosive demolition of building structure, subway and road construction sites. In December, 2006, Korean Government and professional society (KSEE) established the blasting guidelines of Modern Vibration Controlled Blasting Method (MVCBM) which is an unprecedented in the world.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.3
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• pp.105-111
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• 2010

It is very important to select carefully backfill materials and build for the structural integrity of abutment in bridge. In general, backfill materials of unbound crushed stones (SB-1) are used to provide the safety of abutment structure and to reduce differential settlement around abutment that is significantly related with performance of road pavement under working conditions. In this study, to evaluate the compatibility of backfill materials at abutment and to develop the abutment design program, i) basic properties of subgrade soils in Korea, ii) evaluation of deformational characteristics of backfill materials from RC/TS tests, cyclic TX tests and Creep tests were accomplished.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.340-343
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• 2006

As the needs of consumer on ride comforts increase and the reduction of road traffic noise tightened step by step, the power unit noise emitted by cars has been reduced. It has been found that tire noise dominates noise produced by the power-train when vehicles are driven at high speeds. Therefore, in these days, tire/pavement noise is concerned. Tire/pavement noise is affected by pavement type and vehicle???s transmission loss. Tire noise mechanism is produced by several mechanisms. The sound of tire can propagate either through the air or through the structure of vehicle. Pattern noise is the result of pressure variations through the air to the interior side of vehicle. Especially, on smooth asphalt the periodicity of tread design, pitch sequence is important factor, which have an influence on the reduction of tire noise.

• Journal of KSNVE
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• v.5 no.1
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• pp.29-35
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• 1995

This paper presents the simultaneous optimal design of structure and LQG control systems for the improvement of riding comforts of active vehicle suspension systems. The performance index of riding comforts is extended to include frequency-weighted acceleration in the quadratic cost functional. Janeway human response curve with respect to acceleration is used to verify the usefulness of the presented method. The method is applied to a half model of an active vehicle suspension systems with elastic body moving on randomly profiled road. The values of stiffness of suspensions are used for the structural design variables. The conjugate gradient method is used for optimization. The simulated results of simultaneous optimization with frequency-weighted cost functional are compared with those without frequency- weighted cost functional.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.10a
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• pp.613-616
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• 2012

A multi body simulation (MBS) model is developed for predicting the impact harshness of the vehicle. Impact harshness is the vehicle performance to evaluate the impulsive vibration behavior during driving over an obstacle of the road. Thus, the approach is simulated on the time domain for considering the transient behavior of the vehicle. The validity of vehicle component modeling of bushes, dampers and structure flexibilities is verified. The simulations are compared with the test results in both of vertical and longitudinal directions. In particular, the vertical vibration of the vehicle is significantly affected by the body flexibility. Through the sensitivity analysis, main factors for the impact harshness performance are investigated.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.76-78
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• 2005

본 교통사고 동영상 DB 설계의 연구 목적은 교통사고 자동기록장치에서 수집되는 교통사고 동영상 자료를 효율적으로 활용하기 위한 교통사고 동영상 DB 구축 방안에 관한 연구이며, 이를 위해 ISO/IEC 11179 표준인 MDR을 이용한 교통사고 동영상 DB 논리 모델을 제안하는 데 있다. 본 논문에서 제안하는 DB구조를 통해 실시간 대용량 교통사고 동영상 데이터에 대한 데이터의 생성, 관리 및 검색 성능을 향상시킬 수 있을 뿐만 아니라, MDR 표준 개념 적용으로 상호 이질적인 DB 간의 상호운용성(interoperability)이 증대된다.

• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.101-106
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• 2007

A time-lapse microgravity survey on a newly widen road at Muan, where limestone cavities are developed, for monitoring the change of the subsurface density distribution before and after grouting. Microgravity monitoring is identified as a quick, easy and cost effective. But, it requires strict data acquisition and quality control due to the differences of conditions at measurements. The survey was carried out two times, that is, October 2005 and September 2006. The data were adjusted for reducing the effects due to the different condition of each survey. The processed data acquired in 2005 and 2006 were inverted into the subsurface density distributions. They show the change and development of density structure during the lapsed time, which implies the effects of grouting.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.279-286
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• 2002

This study is concerned wiか the practical optimum design of concrete framed structures considering serviceability - deflection, crack, fatigue. The optimizing problems of framed structure are formulated with the objective function and the constraints which take the section properties as the design variables. The objective functions are formulated as the total cost of the structures and the constraints are derived by using the criteria with respect to safety and serviceability based on the part of concrete bridge in the Korea standard code of road bridge. The SLP method is introduced to solve the formulated nonlinear programming problems in this study and tested out through the numerical examples. This developed optimizing algorithm is tested out and examined through the numerical examples for the practical use of design on the concrete framed structures. And their results are compared and analyzed to examine the possibility of optimization, the applicability and the convergency of this algorithm.

• Journal of Magnetics
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• v.10 no.1
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• pp.36-39
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• 2005

We report element-resolved and interface-sensitive magnetization reversals investigated from an oppositely exchange-biased NiFe/FeMn/Co structure by employing soft x-ray resonant Kerr rotation measurements. We have found not only switchable uncompensated antiferromagnetic regions with its sizable thicknesses at both interfaces of the FeMn layer but also their strong coupling to the individual ferromagnetic layers. These experimental results provide a better insight into experimentally observed reductions in exchange-bias field on the basis of an interface-proximity model proposed in this work.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.494-499
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• 2005

Transportation routes by land like a human being blood vessel should exist for economic and trade exchange in Northeast Asia. Thinking from this point of view. I believe that TSR(Trans Siberian Railroad) and TCR(Trans Chinese Railroad). which will be connected with I would like to talk about .not only the effects of various international railroads and their connections but also economic activation TKR(Trans Korean Railroad). can play important roles. In this study, and effects in Northeast Asia which will be resulted from various international railroads construction. I tried to figure out comparative superiority and comparative advantage of the trade structure and industries in South and North Korea to find out the possibility of economic unification in East Asia. especial1y in Northeast Asia. This study also includes the effort to find out how trade exchange between South and North Korea can be expanded as a result of being a member of East Asia economic zone.