• Journal of Chest Surgery
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• 제25권4호
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• pp.435-437
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• 1992

We experienced one case of immature teratoma at anterior mediastinum. the patient was Syears old female whose complain were cough and chest pain. Chest film showed mass density St the lower half of the Rt chest. Chest CT showed inhomogenous mass which have some calcified area. At the time of operation, 12x10x13cm sized mass have smooth surface and its stump elongated to the thymus. a-FP level, preoperative 22.5ng/ml, was decreased to 9.7ng/ml after operation. Postoperative adjuvant chemotherapy was performed with Vinblastin, Bleomycin and Cisplatin combination. The patient had an uneventful postoperative or postchemotherapy course and was discharged in a good condition.

• 마이크로전자및패키징학회지
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• 제18권3호
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• pp.53-57
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• 2011

In the modern packaging technologies highly condensed metal interconnects are typically formed by highcost processes. These methods inevitably require the precise controls of mutually dependant process parameters, which usually cause the difficulty of the change in the layout design for interconnects of chip to-chip, or chip-to-substrate. In order to overcome these problems, the unique concept and methodology of self-assembly even in micro-meter scale were developed. In this report we focus on the factors which influenced the self-formed bumps by analyzing the phenomenon experimentally. In case of RMA flux, homogenous pattern was obtained in both plain surface and cross-section surface observation. By using RA flux, the phenomena were accelerated although the self-formtion results was inhomogenous. With ussage of moderate RA flux, reaction rate of the self-formation was accelerated with homogeneous pattern.

• 대한두경부종양학회지
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• 제6권2호
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• pp.114-118
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• 1990

A clinical study of 37 cases with thyroid nodules, which were treated by surgical excision and confirmed pathologically at the Department of Surgery, Chonnam National University Medical School, from Dec. 1988 to Feb. 1990, was conducted and following results were obtained in ultrasonographic evaluation of thyroid nodules. 1) The thyroid adenoma were showed well-defined margin, homogenous internal echo and surrounding Halo, but thyroid cancer were showed ill-defined margin, inhomogenous internal echo and no surrounding Halo. 2) The sensitivity of high resoution ultrasonography compared with pathologic diagnosis to thyroid cancer was 87.5%, specificity 94.1%, accuracy 88%, false positive 5.88%, and negative 12.5%.

• 대한정형외과스포츠의학회지
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• 제5권1호
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• pp.81-84
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• 2006

Rupture of the rectus femoris at the musculotendinous junction is very rarely reported in the literature, especially which is caused by chronic repetitive stimulation. A 21 year old soldier complained of progressing right thigh pain and mass for 8 weeks after military training. MRI of the right thigh showed inhomogenous mass lesion suspecting soft tissue tumor. However ultrasonographic examination showed torn retracted rectus femoris tendon at musculotendinous junction. One year after primary repair of ruptured tendon, the patient is free from symptoms and returned to full previous activities. Knowledge of this sonographic and MRI finding will help the surgeon to diagnose and treat this rare injury.

• Journal of Chest Surgery
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• 제35권8호
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• pp.626-629
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• 2002

해면상 혈관종은 종격동에 발생한 혈관종중 가장 많은 형태로 주로 전종격동에 발생하고 그 빈도가 매우 드물다. 환자는 13세된 여아로 우연히 발견된 종격동 종괴로 수술적 절제를 하여 해면상 혈관종으로 판명되었다. 술후 추적한 x-ray 검사상 재발의 소견이 없으며 수술적치료시 너무 광범위한 무리한 박리와 절제는 필요하지 않을 것으로 보인다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1284-1288
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• 1990

In this paper, we are going to study the stabilization of the semilinear heat equation with inhomogenous boundary conditions, whose solutions are not (in general) stable. Here, we use the discrete-time feedback inputs through the boundary of geometric domain to the semilinear system under some additional conditions and assumptions. It is shown that under these conditions, the stabilization can be realized by applying pole assignment argument to the principal linear part of the system and that the solutions exist globally in discrete-time t without any finite escape time.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1996년도 추계학술대회논문집
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• pp.150-156
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• 1996

The cold rolling of metal sheets leads to the formation of an inhomogeneous microstructure and texture. The type and sharpness of texture through the thickness and the degree of inhomogeneity depend on the friction between rolls the rolled material and the geometry of the rolling gap. In order to follow the effect of friction, two kinds of stecimens were prepared by applying with and without lubrication during the cold rolling. Although the deformed microstructure of the specimens rolled without lubrication was much inhomogenous than that of the specimens rolled with lubrication, the effect of lubrication on the cold rolling texture was not found. the recrystallization behavior was strongly dependent on the deformation process. Thus, the retardation of the recrystallization was observed in the specimens rolled without lubrication.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1996년도 추계학술대회논문집
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• pp.157-165
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• 1996

Characteristics of microstructure, hardness and wear of two AI-20Si-5Fe-2Ni materials produced by powder metallurgy and spray forming respectively were studied at temperatures up to 560$^{\circ}C$. Above 300$^{\circ}C$, the microstructure of powder processed alloy became inhomogenous, whereas the spray formed alloy showed homogeneous microstructures. Hardness of both alloys was increased between 300$^{\circ}C$~490$^{\circ}C$ in both alloy. It was interpreted that increase in hardness was mainly related to the formation of stable and fine intermetallic phase from metastable one. It was showed that hoogenity of microstructure in the rapidliy soldified affected directly wear property.

• 한국초전도ㆍ저온공학회논문지
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• 제25권4호
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• pp.1-4
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• 2023

Recently, a claim of material, named LK-99 (a lead apatite-based compound), exhibiting a superconducting transition temperature of over 400 K under standard atmospheric pressure, was reported [1, 2]. This claim has generated considerable attention from scientists worldwide. Here, we synthesized five LK-99 samples following the method detailed in the original papers [1, 2], and measured structural and resistivity data for each of these samples. The structure of the synthesized samples (P6₃/m, a=9.82 Å , c=7.34 Å ) was very close to the reported one. Contrary to the report, however, no hint of room-temperature superconductivity was noted from any of the samples. The results of Energy-dispersive X-ray spectroscopy (EDXS) measurements demonstrate that the atomic distribution in the sample was inhomogenous, and unreacted precursors were included in the samples. To investigate the intrinsic superconducting properties of LK-99, we propose to synthesize samples having high structural purity and chemical uniformity.

• 비파괴검사학회지
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• 제27권3호
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• pp.231-238
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• 2007

Ultrasonic inspection of austenitic steel weldments is a truly difficult task due to complicated wave propagation phenomena such as beam skewing, splitting and distortion. In order to understand these phenomena and design proper inspection procedures, simulation is increasingly paid more attention to. This article addresses a ray tracing based approach to determine incident angle and position of optimal wave mode ultrasonic beam for flaw detection in anisotropic and inhomogeneous austenitic steel weldments. Specially, the optimal mode of ultrasonic wave wave is selected by ray tracing simulation, and an optimization approach based on ray tracing and bi-section search is proposed in order to find the ray path connecting two given points in weldments. With help of this approach, the optimal incident angle and position of ultrasonic beam can be determined for a given flaw position.