• 대한기계학회논문집
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• 제5권2호
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• pp.122-130
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• 1981

Equation of equilibrium is derived and solved for an infinite isotropic solid under applied hydrostatic stress which is uniform at large distance, and disturbed by a spherical precipitate which has isotropoc elastic constants dirrerent form those of the matrix. A linear strain hardening behavior of the matrix is assumed, and an elasto-plastic sloution is obtained. The difference of the total strain energy stored inthe infinite solid with and without a precipitate is computed, and compared with that for purely elastic case. Finally the effect of the ratio of the bulk modulus of the precipitate to that of the matrix and the effct of linear strain hardening rate on the plastic zone size and the energy difference are discussed.

• 정보와 통신
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• 제31권2호
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• pp.71-82
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• 2014

본 논문에서는 물리 계층에서 보안을 고려한 시스템을 제공하기 위해 Gaussian Wiretap Channel 상황에서 보안 전송을 가능하게 하는 보안 전처리 기법의 설계 방법에 대해서 살펴본다. 무선 통신 채널의 경우, 통신 채널이 누구에게나 개방되어 있기 때문에 무엇보다도 보안에 취약하다. 하지만 숨기고자 하는 보안 메시지를 채널 부호화 및 변조 과정 이전에 보안을 위한 전처리 기법을 적용함으로써 물리계층에서 데이터를 보다 안전하게 전송하는 것이 가능해진다. 이를 위해 기존의 Random하게 생성된 Scrambling matrix를 이용하여 물리계층 보안을 유지하는 전처리 기법을 바탕으로 Scrambling matrix의 hamming distance를 이용하여 높은 보안성 및 신뢰도를 가지는 Scrambling matrix 설계 방법을 제안한다. 또한 부호율 1을 가지는 soft decision decoding 기반의 새로운 보안 전처리 기법을 제안함으로써 물리계층에서의 보안성 확보 가능성을 확인하였다.

• 한국자원식물학회지
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• 제22권3호
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• pp.242-247
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• 2009

Randomly Amplified Polymorphic DNA (RAPD) was performed to define the genetic variation and relationships of Artemisia capillaris. Fifteen populations by the distributions and habitat were collected to conduct RAPD analysis. RAPD markers were observed mainly between 300bp and 1600bp. Total 72 scorable markers from 7 primers were applied to generate the genetic matrix, and 69 bands were polymorphic and only 3 bands were monomorphic. The genetic dissimilarity matrix by Nei's genetic distance (1972) and UPGMA phenogram were produced from the data matrix. Populations of Artemisia capillaris were clustered with high genetic affinities and cluster patterns were correlated with distributional patterns. Two big groups were clustered as southern area group and middle area group. The closest OTUs were GW2 and GG1 in middle area group, and GB1 from southern area group was clustered with OTUs in middle area group. RAPD data was useful to define the genetic variations and relationships of A. capillaris.

• 대한기계학회논문집
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• 제17권7호
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• pp.1751-1760
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• 1993

The squeeze casting process is considered as an attractive way to form the primary product of near net shape metal matrix composites for wide use in automobile industry. To understand for infiltration limit in squeeze casting processes, the SAFFIL short fiber preform of volume fraction $10%{\sim}23%$ were fabricated by vaccum pumping and speed control press, and the optimal condition for fiber preform fabrication had been experimentally obtained. The composite materials were fabricated by forced infiltration of molten metals such as Al6061, Al7075, pure Al, AC8A, and Al2024. The infiltration distance and deformation of fiber preform are observed, and tensile strength were measured from at the room temperature.

• 대한수의학회지
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• 제57권4호
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• pp.249-252
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• 2017

Rabies virus (RABV) causes a neurological disease in warm-blooded animals that is nearly always fatal. In this study, we analyzed the matrix (M) genes in 10 Korean street RABV strains isolated from two Provinces during 2011-2013. The M genes in these 10 Korean strains were highly conserved during 1999-2013. Phylogenetic analysis revealed they were closely related to the M genes of RABVs isolated in northeastern China. Specific amino acid substitutions were identified in the KRVB1206, KRVF1301, and BV9901PJ strains. However, functional domains, including those involved in virus production and pathogenicity, were conserved in all 10 strains.

• International Journal of Aeronautical and Space Sciences
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• 제17권2호
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• pp.204-213
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• 2016

A differential game theory based approach is used to develop an automated maneuver generation algorithm for Within Visual Range (WVR) air-to-air combat of unmanned combat aerial vehicles (UCAVs). The algorithm follows hierarchical decisionmaking structure and performs scoring function matrix calculation based on differential game theory to find the optimal maneuvers against dynamic and challenging combat situation. The score, implying how much air superiority the UCAV has, is computed from the predicted relative geometry, relative distance and velocity of two aircrafts. Security strategy is applied at the decision-making step. Additionally, a barrier function is implemented to keep the airplanes above the altitude lower bound. To shorten the simulation time to make the algorithm more real-time, a moving horizon method is implemented. An F-16 pseudo 6-DOF model is used for realistic simulation. The combat maneuver generation algorithm is verified through three dimensional simulations.

• Transactions on Electrical and Electronic Materials
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• 제12권4호
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• pp.135-139
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• 2011

In an effort to develop new electrical insulation materials, four different kinds of organically modified layered silicate were incorporated into an epoxy matrix to prepare nanocomposites for electrical insulation. Five wt% of organically modified layered silicates were processed in a planetary centrifugal mixer in an epoxy matrix, and the thermal, mechanical, and electrical properties of the cured epoxy/layered silicate were investigated. The morphology of the nanoscale silicate dispersed in the epoxy matrix was observed using transmission electron microscopy, and the interlayer distance was measured by wide-angle X-ray scattering diffraction analysis.

• Journal of Information Processing Systems
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• 제10권1호
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• pp.69-80
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• 2014

The free distance of (n, k, l) convolutional codes has some connection with the memory length, which depends on not only l but also on k. To efficiently obtain a large memory length, we have constructed a new class of (2k, k, l) convolutional codes by (2k, k) block codes and (2, 1, l) convolutional codes, and its encoder and generation function are also given in this paper. With the help of some matrix modules, we designed a single structure Viterbi decoder with a parallel capability, obtained a unified and efficient decoding model for (2k, k, l) convolutional codes, and then give a description of the decoding process in detail. By observing the survivor path memory in a matrix viewer, and testing the role of the max module, we implemented a simulation with (2k, k, l) convolutional codes. The results show that many of them are better than conventional (2, 1, l) convolutional codes.

• 경영과학
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• 제11권3호
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• pp.55-65
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• 1994

Given the flow matrix, plant size and department sizes, the algorithms in this paper provide the layout with rectilinear distance. To construct automated facility design, cut tree approach is employed. A branch and bound computer code developed by Tillinghast is modifided to find the feasible fits of departments without shape distortion in the plant rectangle.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.318-321
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• 2007

Since human listening is very sensitive to sound, a subjective index of a sound quality is required. Therefore, in the analysis for each situation, the sound evaluation is composed with sound quality factor. Many researchers spends their effort to make a more reliable and more accurate of sound in term of sound quality index for various system noise. The previous methods to evaluation of the SQ about vehicle interior noise are linear regression analysis of subjective SQ metrics by statistics and the estimation of the subjective SQ values by neural network. But these are so depended on jury test very much that they result in many difficulties. So, to reduce jury test weight, we suggested a new method using Mahalanobis distance for SQ evaluation. Threrefore, in this study Mahalanobis distance for the vehicle interior noise was derived using the objective SQ except jury test. Finnaly, the results of the SQ evaluation was analyzed discrimination between reference and abnormal group.