• Journal of Conservation Science
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• v.30 no.4
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• pp.395-407
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• 2014

In this study, firing temperature of bricks from the Songsanri tomb complex is interpreted based on the mineralogical and physical changes of soil samples fired at different temperature. When soil samples were burned at 500 to $1,200^{\circ}C$, phase transition of clay minerals affected the mineralogical composition and microstructure, which leaded to alteration of physical features as color, water absorption and porosity. Mineralogical composition can be assumed to vary with the temperature by mineral phase stability, however, color, water absorption, porosity and microstructure had slow change under $1,000^{\circ}C$, and had rapid change from 1,000 to $1,200^{\circ}C$. Upon the mineral and physical alteration of soil, firing temperature of bricks from the Songsanri tomb complex were estimated. Some bricks were over fired at temperature more than $1,200^{\circ}C$, some high-burned bricks were fired from 1,100 to $1,200^{\circ}C$, some bricks were fired by 900 to $1,000^{\circ}C$ and some bricks ere assumed not to be fired. Henceforward mineralogical and physical study can be applied to interpretate more precise firing temperature.

• Journal of the Mineralogical Society of Korea
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• v.21 no.2
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• pp.209-224
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• 2008

Various types of high-purity limestone, which occurred in the Pungchon Formation, are examined to understand applied-mineralogical factors controlling their calcination characters with respect to the ore characters. To do this work, systematic characterization and determination were carried out for the limestone ores and their calcination products in a fixed heating condition, and the results were correlated and discussed. During the calcination experiment, a phase transition from calcite to quicklime begins to occur selectively in the physical weak zones such as grain boundary, cleavage and twin planes. All the fabrics of original limestones are preserved in the resultant quicklime. In addition, crystallinity of the quicklime was advanced, as the aging time of calcination was increased. Major controlling factors on the calcination effects of the high-purity limestone are elucidated to be the degree of development of cleavage and twin, together with crystallinity and textures in the limestone ore. Especially, lower crystallinity and dense interlocking fabrics obviously play advantageous role in all the calcination characters. But the development of cleavage and twin affects negatively on the calcination characters on account of favoring decrepitaion of quicklime in the lime manufacturing. Thus, the high-purity limestones characteristic of marble fabrics and relatively lower crystallinity are comparatively advantageous for the uses of lime manufacture.

• 기계와재료
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• v.23 no.3
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• pp.82-95
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• 2011

다결정압연판재는 열가공공정을 거쳐서 생산되므로 공정의 특성을 반영하는 미세조직/집합조직 특성을 가지게 된다. 결정립들은 특정방향으로 배향하고 결정립의 형상과 크기도 변화한다. 이러한 변화는 거시적으로 다결정판재의 이방성으로 귀결이 되는데, 근본적으로 판재를 구성하는 단결정들의 기계적 물성이 각각의 방향별로 이방성을 띄기 때문이다. 본 자료에서는 압연공정시 다결정판재의 수직/평면이방성의 발생원인을 집합조직과 결정소성학을 이용하여 제시하고자 하였다.

• The Journal of the Korean bone and joint tumor society
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• v.19 no.2
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• pp.92-96
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• 2013

Heterotopic ossification is an abnormal bone formation after surgery or without any reason. Large joint, such as hip and knee joint, is a known most common site. Operation itself and postoperative early range of motion exercise are risk factors. We present a case of heterotopic ossification mimics neurogenic tumor after high tibial osteotomy.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.03a
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• pp.94-97
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• 1997

금속을 반고상 상태에서 성형하기 위하여 미세조직학적 거동을 밝히기 위해, 본 연 구에서는 높은 비강도, 내마모성을 가진 과공정 Al-Si 합금을 반응고 가공하였을 때의 미세 조직과 상온 가공 후 반고상 온도로 일정시간 유지하였을 때의 미세조직을 관찰하였다. 일 반주조시의 개량 원소 P과 Sr을 첨가하였으며 쐐기형 주조재, 압연재, Si 입자강화 Alrl 복 합재료를 반고상 상태로 가열한 미세조직을 관찰하여 초정 Si입자의 형상 변화를 관찰하였 다. 반응고 교반시 초기에는 P과 Sr의 첨가에 의해 초정 Si입자가 미세화 되었으나 교반이 지속되어 가면서 이러한 경향은 감소하였으며 구상에 가까운 형태로 변화 하였는데, 이는 교반이 지속되면서 첨가 원소의 효과보다 교반 자체의 미세조직 변화 기구에의 의존도가 높 아지기 때문인 것으로 사료된다. 냉각속도를 달리한 쐐기 형상에서의 금형에서 주조된 미세 조직을 관찰한 결과 냉각속도가 느릴 때에만 첨가원소의 영향이 나타났으며, 반고상 온도 유지 후 초정 크기에는 큰 변화가 없었으나 $\alpha$-halo가 형성되고 미세한 Si입자가 생성되었 다. 이는 입자 크기의 성장에 따른 주위의 농도구배로 인해 생성된 것으로 사료된다. 압연시 첨가원소는 핵생성과 재결정을 촉진시켜 초정 Si의 크기를 크게 감소시켰다. 반용융 처리시 초정 Si입자는 약간 성장하였으며, $\alpha$-halo도 생성되었다. 압출한 시료를 반용융 처리한 경 우 Si입자의 형상 변화는 거의 없었으며, Si입자에 형성되어 있던 산화막이 기지와 초정 Si 압자간의 확산장벽으로 작용하여 $\alpha$-halo가 거의 생성되지 않았다. 반응고 교반시 미세조직 변화 기구로는 취성파괴, 합체, 마모를 제안하였으며, 각 공정에서의 초정 Si결정의 크기를 비교하였을 때 45$\mu\textrm{m}$ 이하의 분말을 섞어 압출하였을 때 가장 작은 초정 Si입자 크기를 얻음 을 볼 수 있었다.

• Journal of the Microelectronics and Packaging Society
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• v.31 no.2
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• pp.36-44
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• 2024

Copper electrodeposition technology is essential for producing copper films and interconnects in the microelectronics industries including semiconductor packaging, semiconductors and secondary battery, and there are extensive efforts to control the microstructure of these films and interconnects. In this study, we investigated the influence of crystallographic orientation on the local plastic deformation of copper films for secondary batteries deformed by uniaxial tensile load. Crystallographic orientation maps of two electrodeposited copper films with different textures were measured using an electron backscatter diffraction (EBSD) system and then used as initial conditions for crystal plasticity finite element analysis to predict the local plastic deformation behavior within the films during uniaxial tension deformation. Through these processes, the changes of the local plastic deformation behavior and texture of the films were traced according to the tensile strain, and the crystal orientations leading to the inhomogeneous plastic deformation were identified.

• The Journal of Korean Physical Therapy
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• v.12 no.2
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• pp.255-265
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• 2000

The term 'myositis ossificans' encompasses four categories of clinicopathological disorders. The first, myositis ossificans progressive(fibrodysplasia ossificans progressive), is a rare genetic disease characterized by progressive heterotopic ossification involving skeletal muscle, tendon, ligaments, and fascia, with congenital malformation of the great toes, and usually microdactyly, monophalangism, and mal formed proximal phalanges. with valgus deformity of metatarsophalangeal joint. The ossification begins shortly after birth and may contribute to the patient's death. The second, heterotopic ossificans, can occur in patients with neuromuscular and chronic diseases such as paraplegia, poliomyelitis, polymyositis, bum, tetanus, and infection. But the lesions in these cases often lack the typical histologic features of myositis ossificans. The third, myositis ossificans traumatica, is the most common; it develops in response to soft tissue trauma such as a single severe injury, minor repetitive injures, fracture, joint dislocation, stab wound, or surgical incision. The forth, nontraumatic myositis ossificans, also designated :pseudomalignant osseous tumors of extraskeletal soft tissues' and 'psedomalignant myositis ossificans', occurs in persons repeated small mechanical injures or nonmechanical soft tissue injuries due to local ischemia, inflammation. or other factors cannot be ruled out in such cases.

• Journal of Gastric Cancer
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• v.6 no.1
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• pp.43-46
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• 2006

An adenomyoma of the gastrointestinal tract is a rare, benign, tumor-like condition histologically characterized by glandular structures embedded within a smooth muscle stroma. An adenomyoma has been considered to be as an abortive variant of an ectopic pancreas. An ectopic pancreas is defined as the presence of pancreatic tissue that lacks anatomic and vascular continuity with the main body of the pancreas. Common sites of an ectopic pancreas are the stomach, duodenum, and upper jejunum. An adenomyoma may rarely undergo a malignant transformation or cystic dystrophy. Recently, the authors an experienced a case of an incidental adenomyoma of the stomach associated with early gastric carcinoma. We report that case here.

• Korean Journal of Materials Research
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• v.4 no.2
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• pp.241-249
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• 1994

We studied on the effects of hot-worm rolling on recrystalized structures and tensile strength in over-aged 7075 A1 alloy, to develop the process for improving properties. It showed more clear effect of the grain refinement with over-aging before plastic deformation. That means, the coarse precipitates from over-aging play a roll as nucleation sites in the course of recrystallization. And on this study, the relations between yield strength and grain size was not satisfied with Hall-Petch equation because of the elongated structure, but the yield strength is proportional to aspect ratio of grains. In TMT process for improving strength and toughness, the worm working is available for increase of those properties than cold working.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.445-448
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• 2009

The present work deals with microstructure and tensile deformation of nanostructured dual-phase steel consisting of ferrite and martensite phases. Prior to deformation, a fully martensite phase is prepared and then processed by equal channel angular pressing (ECAP) and subsequent annealing. Room-temperature tensile properties are examined and compared to those of dual-phase steels with coarse grains. Due to the combined effects coming from the grain refinement of both phases and their uniform distributions, the nanostructured dual-phase steel exhibits better strength and ductility than coarse grained counterpart, achieving ${\sim}1\;GPa$ and ${\sim}20%$ for tensile strength and elongation, respectively.