• 한국지구물리탐사학회:학술대회논문집
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• 2007.12a
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• pp.43-51
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• 2007

In order to investigate the velocity structure of the southern part of the Korean peninsula, exploded seismic signals were recorded for 120 s along a 294-km WNW-ESE line and 150 s along a 335-km NNW-SSE line in 2002 and 2004, respectively. Velocity tomograms were derived from inverting P-wave and S-wave first arrival times. The raypaths indicate several midcrust interfaces. The shallowest one is at the approximate depth of $2{\sim}3\;km$ with refraction velocities of approximately Vp=6.0 and Vs=3.5 km/s, respectively. The second one of $15{\sim}17\;km$ depth has refraction velocities of approximately Vp=7.1 and Vs=3.7 km/s, respectively. The deepest significant interface varies in depth from 30.8 km to 36.1 km. The critically refracting Vp of $7.8{\sim}8.1\;km/s$ and Vs of $4.2{\sim}4.6\;km/s$ along this interface which may correspond to the Moho discontinuity. The velocity tomograms show (1) existence of a low-velocity zone centered at $6{\sim}7\;km$ depth under the Okchon fold belt and the Yeongnam massif, (2) extension of the Yeongdon fault down to greater than 10 km, and (3) existence of high-velocity materials under the Gyeongsan basin less than 4.2 km thick.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.3
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• pp.97-104
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• 2000

Studies on the principle of traditional moulding techniques of architecture or structure are very important in the point of the work could accomplish succession to modern design. As an attempt of these work, this study tried to examine traditional moulding techniques applied in planes of ancient architecture and structure closely. The major findings of this study are summarized as follows; It was verified that planes of ancient Korean architectures and structures analyzed in this study was moulded by its multiple partitions with the six or eight partitions of circumference as the fundamental form. The well unearthed in kyong-bok palace recently was moulded by a concentric circle assumed form of 4 circle which was extended with equal interval and divided into multiple of 8 partition of circumference. Chon-duk-jung in chang-duk palace also was moulded by a concentric circle assumed form of 3 circle extended with equal interval, but circle were divide by 6 partitions. It was also found that 6$^{\circ}$§8 partitions of circumference(or its multiple partition) was applied to not only above structures but also the moulding planes of ancient architecture, and as a results, figures revealed in architectures analyzed is classified into three classes. And, this study analyzed arrangements of two temples. As a results, it is discovered that the Grid used in moulding planes of each building fixed the arrangement of buildings. Therefore, moulding by equal partition of circumference decided the form of each building and the relation of element at the same time.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.6-10
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• 1998

The complex[Cu(L)](ClO4)2 (1) (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized and structurally characterized. The complex 1 crystallizes in the monoclinic system, space group P21/n with cell parameters a=8.208(2)Å, b=13.339(6) Å, c=10.752(5) Å, β=111.02(4)˚ Z=2. Least-squares refinement of 1 led to a R(RW)factor of 0.073 (0.142) for 617 observed reflections of F0>40(F0). The crystal structure of 1 has a square-planar geometry and adopts the trans-III conformation.

• 한국전자현미경학회:학술대회논문집
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• 2002.11a
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• pp.33-35
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• 2002

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.285-289
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• 2002

In this paper, microstrip line-probe feeding patch array antenna with center frequency 5.8㎓ is designed and manufactured. The microstrip line - probe feeding structure has broadband characteristic and be able to modify the array structure for improving antenna gain. In this result, microstrip line-probe feeding patch array antenna has 17.6% bandwidth and 8㏈i antenna gain, respectively.

• Journal of Integrative Natural Science
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• v.8 no.4
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• pp.250-257
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• 2015

The crystal structure of the potential active 3-(4-ethylphenyl)-3H-chromeno[4,3-c]isoxazole-3a(4H)-carbonitrile ($C_{19}H_{16}N_2O_2$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the monoclinic space group $P2_1/c$ with unit cell dimension a=6.6869 (8) ${\AA}$, b=15.8326 (19) ${\AA}$ and c= 15.237 (2) ${\AA}$ [${\alpha}=90^{\circ}$, ${\beta}=100.663^{\circ}$ and ${\gamma}=90^{\circ}$]. In the structure chromene, isoxazole and carboxylate are almost coplanar each other. All geometrical parameters revelled that chromene ring of pyran ring adopt sofa conformation. The crystal packing is stabilized by intermolecular C-H...N and C-H...O hydrogen bond interaction.

• Journal of Sericultural and Entomological Science
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• v.39 no.1
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• pp.67-72
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• 1997

As a condition for obtaining the silk I type crystal that has stability and high reproducibility, after dissolving silk fibroin crystalline part (Fcp), the changes of recrystallized crystal structure according to dialytic pH were examined by x-ray diffraction and differential thermal analysis. The Fcp was obtained from the aqueous solution of silk fibroin enzymatic proteolyzed by chymotrypsin. The crystal structure of Fcp showed silk II type. When the Fcp was dissolved by 10M LiBr aqueous solution, the Fcp1 showed the silk II type at pH 9. However, besides the silk II type, the silk I type structure begins to appear at pH 8 and only the silk I type structure was found below pH 6. On the other hand, the Fcp2 that calcium chloride was used in the dissolution found only the silk I type crystal structure below pH8.

• Journal of IKEEE
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• v.26 no.1
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• pp.129-132
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• 2022

In this paper, a technique for optimizing the sub-array system structure that can minimize the side lobe level of the phased-array antenna is proposed. Optimization of the proposed array antenna structure is to adjust the spacing between sub-arrays and sub-arrays by using a hexagonal array structure of one sub-array and a hexagonal sub-array for six hexagonal arrays, and thus the entire phased array antenna system of the radiation pattern was optimized. Compared to the 2-dimensional planar antenna system, the proposed technique maintains a gain of 24.3 dBi and a half-power beam-width of 8.46 degrees without change, and only reduces -3.4 dB and -6.5 dB in the x-axis and y-axis directions, respectively.

• Explosives and Blasting
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• v.12 no.1
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• pp.5-31
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• 1994

On the Seoul Sub-way Tunnel works (8-6 site ). Cautious blasting works were so effectivelly tarried out the vibration record were under 0.3cm /sec and blasting noise was under 75dB which was measured at the ground of house. As a result cautious blasting works under above allowable value was not influenced the structure of house and living. On the architectural survey, There were some hair crack on the wall and floors but this was not a crack from balsting work.

• Proceedings of the KIEE Conference
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• 2002.04a
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• pp.93-95
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• 2002

본 논문은 3상 6/8 SRM에 대한 회전자와 고정자의 구조, 회전자 위치 검출, 인버터의 특성에 관한 연구이다. 또한 선형구간에서의 고정자 극호 상수와 회전자 극호 상수의 범위에 대해 해석하였다. 그리고 이를 2D FEM 해석을 통하여 최적의 고정자 극호 상수와 주스위치의 최적 스위치 오프각을 해석하였다. 또한 시작기의 제작을 통하여 실험으로 해석결과를 입증하였다.