• Journal of the Korean Professional Engineers Association
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• v.30 no.1
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• pp.5-15
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• 1997

방사선들 중에서 감마선은 우리의 몸 속을 깊숙이 침투할 수 있다. 그런 감마선이 우리 몸을 투과할 때, 체세표를 이룬 원자들의 궤도전자들과 충돌하면서 소멸된다. 우리는 그런 현상들을 물질과의 상호작용 이라 부른다. 방사선과 물질과의 상호작용은 원자의 단위에서 일어난다. 감마선이 물질과의 상호작용들은 물리적으로는 광전자 산란 효과, 컴프턴 산란 효과 그리고 전자쌍 생성효과 등으로 구분하여 설명된다. 방사선이 우리의 몸 속에서 체세포의 원자와 충돌하여 생기는 자유전자들은 몸 속에 남게 되고, 그들은 몸 속을 상당 기간 동안 배회하면서 인체의 생명 현상을 유지시킬 생화학 작용의 기능들을 약화시키기도 하고, 악성인 암세포들을 만들어내기도 하므로 건강 유지에 불리하게 작용한다. 따라서 감마선에 쪼여 생긴 자유전자들은 우리의 정상적인 건강 조건들을 해치는 주된 요소가 된다.

• Journal of the Korea Concrete Institute
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• v.29 no.1
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• pp.65-75
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• 2017

C-S-H phase is the most abundant reaction product, occupying about 50~60% of cement paste volume. The phase is also responsible for most of engineering properties of cement paste. This is not because it is intrinsically strong or stable, but because it forms a continuous layer that binds together the original cement particles into a cohesive whole. The binding ability of C-S-H phase arises from its nanometer-level structure. In terms of chloride penetration in concrete, C-S-H phase is known to adsorb chloride ions, however, its mechanism is very complicated and still not clear. The purpose of this study is to examine the interaction between chloride ions and C-S-H phase with various Ca/Si ratios and identify the adsorption mechanism. C-S-H phase can absorb chloride ions with 3 steps. In the C-S-H phase with low Ca/Si ratios, momentary physical adsorption could not be expected. Physical adsorption is strongly dependent on electro-kinetic interaction between surface area of C-S-H phase and chloride ions. For C-S-H phase with high Ca/Si ratio, electrical kinetic interaction was strongly activated and the amount of surface complexation increased. However, chemical adsorption could not be activated for C-S-H phase with high Ca/Si ratio. The reason can be explained in such a speculation that chloride ions cannot be penetrated and adsorbed chemically. Thus, the maximum chloride adsorption capacity was obtained from the C-S-H phase with a 1.50 Ca/Si ratio.

• The Magazine of the IEIE
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• v.31 no.6
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• pp.96-109
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• 2004

해수의 물리적 성질은 수온, 염분 그리고 밀도 등으로 특성 지워지며 이러한 특성들의 시공간적인 분포 파악은 해수의 유동, 해양-대기 상호작용 및 해수자원 분포 파악 등에 필수적인 요소로 해양학 연구의 기본 관측 항목이 된다.(중략)

• Progress in Medical Physics
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• v.2 no.2
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• pp.161-173
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• 1991

A statistical approach was carried out to analyze joint moments acting on the six subjects performing a right-handed seated task. The dynamic task analyzed consisted of moving a hand-held weight of lkg mass back and forth in front of a subject's chest at the shoulder level in an upright seated position. We used experimental data obtained in the Biomechanics Laboratory of the University of Michigan. Based on the acquired data from three trials by each subject, moments were calculated using a 3-dimensional biomechanical model at such articulations as wrist, elbow, shoulder, the third lumbar spine, hip, knee, and ankle joints. The linear correlation and the two way analysis of variance were applied to the calculated joint moments in order to investigate inter-subject and inter-trial varations. The results obtained showed that the largest magnitude and deviation of moment was found at the third lumbar spine, that any linear relationship could not be found between moment and its equivalents attempted in this study, and that the maximum value and deviation of moment acting on each joint were statistically the same for all three trials but those were statistically not the same for all six subjects.

• Journal of the Korean Geophysical Society
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• v.9 no.4
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• pp.409-416
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• 2006

Reflection seismic survey has been conducted using R/V Yuzmogeologia of Russia on the area of between northern part of Powell basin and South Scotia Ridge. 48-channel seismic data have been processed using Promax system. Hesperides and Eastern Deep located in the central part of the South Scotia Ridge show similar geological structure comprising two distinct sedimentary layers. The lower layer filled with fault breccia is considered to be formed with the expansion of the deeps. The upper layer is filled with pelagic sediments which implies this layer is formed after the spreading of the deeps has stopped. The south branch of the South Scotia Ridge is characterized by bigger width than the north branch. Topographical depression shown in the south branch is formed by many faults accompanied with the seafloor expansion of Powell basin.

• Journal of Korea Soil Environment Society
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• v.1 no.1
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• pp.81-88
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• 1996

To study the Cd adsorption in the presence of competing ions in soil-solution interphase, three soil samples from the Bt horizon were taken and analyzed for their physical and chemical properties. Adsorption of ethylene glycol monoethyl ether(EGME) and N, were determined to establish the specific surface area of the soils. We attempted to establish a qeneralizing competitive sorption isotherms for soils of entirely different composition of the solid phase, resulting in the routine use as a guidelines for the fate of reactive solute in soil profiles. Many physicochemical factors including competitive adsorption bettween solutes will affect the general adsorption phenomena as shown in a single not only on the soil:solution ratio used, but also on the surface areas of its respective soil samples. This phenomenon was attributed to competition Cd for sorption sites with Mg by different soil constituents. These adsorption isotherms are able to use as examples to demonstrate that this phenomenon can complicate the development of a standardized batch adsorption procedure as well as interpreting fate and adsorption of toxic inorganic compounds.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.206-212
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• 2015

This paper proposes the physical human-robot interaction method that controls the robot arms using ITO touch panel sensor as the skin of robot. To implement physical human-robot interaction, the method of using the force/torque sensor and the method of using tactile sensor created by arranging small element type of sensor have been studied. However, these sensors have the pros and cons in terms of price and performance. This study aims to demonstrate the economy of element type sensor and the accuracy of force/torque sensor through experiment by proposing the method of physical interaction using the touch panel as the skin of robot, and by constructing overall system. The experiment was carried out for the method of controlling the robot arm by installing end-effecter and the method of controlling robot arm by creating the gesture with reference point on the touch panel. Through this experiment, the possibility of teaching control using the touch panel was confirmed.

• Economic and Environmental Geology
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• v.12 no.2
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• pp.79-93
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• 1979

Twenty five samples of the scheelite-powellite series from twelve Korean tungsten deposits of various geologic settings were studied mineralogically and geochemically. Variations in the trace-element contents of the scheelite minerals are considered in relation to geologic settings and mineralogic properties. Scheelites from ore deposits developed in similar geologic settings and under similar physicochemical conditions are characterized by specific combinations of trace elements.

• Journal of the Korean Geophysical Society
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• v.2 no.3
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• pp.169-178
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• 1999

Low-field anisotropy of magnetic susceptibility (AMS) was measured with 247 samples from 17 sites of Pre-Cambrian anorthositic rocks in the Hadong-Sanchong area, southwestern part of the Ryongnam Block. Tectonic stress-direction is defined by the minimum susceptibility (k3) direction, and flow-direction by the maximum susceptibility (k1) direction. Five sites rendered self-consistent NW-SE site-mean tectonic stress-direction. Even though a general fold test for every site was not possible due to the homoclinal nature of the bedding attitudes, a site with various bedding attitudes shows far better clustering of the k3-direction before the bedding-tilt correction. The in-situ NW-SE tectonic stress-direction is consistent over the study area and compatible with petrographic foliation observed in metamorphic rocks in and arround the study area, suggesting a regional compressive force acted after the emplacement of the anorthositic rocks. On the other hand, flow-directions obtained from six sites varies from site to site. Strong-field IRM experiments show predominance of titanomagnetites over a small amount of hematite in some samples.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.10
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• pp.1752-1758
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• 2006

Racing game requires plausible physics model that can be simulated in realtime. Minor artifacts in racing games are easily noticed, and any kinds of games should work interactively. It is difficult to model the accurate tire-ground physics and to integrate the model into realtime environments. In this paper, an efficient and effective 'imaginary wall' model was proposed. The method can be easily implemented because of the simplicity of the physical model used, and the result of the simulation is realistic enough for the racing games.