• The Journal of the Petrological Society of Korea
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• v.14 no.4 s.42
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• pp.195-211
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• 2005

The Kusandong Tuff, known as a representative key bed in the Cretaceous Gyeongsang Basin, is a crystal-rich tuff of pyroclastic flow and surge origin. It is 1-4 m thick and laterally extends for more than 200 km intercalated in the upper part of the Hayang Croup. Observations and analyses of the feldspar crystals in the tuff, using polarizing microscopes, EPMA, and BSE images, reveal that the plagioclase crystals in the tuff were completely albitized (>$97\%$ Ab) whereas those in the southernmost localities where the tuff is rich in fine ash matrix are unaltered or partly albitized. K-feldspars are partly albitized at all localities, irrespective of the matrix content of the tuff, Perthitic textures, chessboard twinning, albitization along micro-fractures and cleavages, and the relationship between matrix content and the degree of albitization suggest that feldspars in the Kusandong Tuff were albitized by Na-rich fluid after burial. Albitization is interpreted to start preferentially along micro-fractures and cleavages and be hampered in matrix-rich tuffs with a low permeability. Original composition of the plagioclases in the Kusandong Tuff is also interpreted to have ranged between oligoclase and andesine ($Ab_{62.5}-Ab_{83.3}$) before the albitization.

• The Korean Journal of Petroleum Geology
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• v.3 no.1 s.4
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• pp.16-27
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• 1995

The Early Miocene Temblor Formation forms an important sandstone reservoir at Kettleman North Dome oil field, California. Sandstones are mostly arkosic in composition except deepest sandstones containing much volcanic rock fragments. Arranged in paragenetic sequence prior to feldspar alteration, the Temblor sandstones contain cements of early calcite, dolomite, quartz, albite, mixed-layer ohloriteismectite (C/S) and smectite, and anhydrite. Diagenetic changes associated with feldspar are albitization of plagioclase, late calcite and laumontite cementation and grain replacement, plagioclase dissolution, and kaolinite cementation. Plagioclase albitization and late calcite and laumontite cementation in Temblor sandstones occurred at the time of maximum burial with temperatures up to $130^{\circ}C$. Volcanic plagioclases were selectively albitized. Most diagenetic changes are interpreted to have occurred before the maior uplift which occurred within the last one million years ago. Since then to the time of hydrocarbon emplacement plagioclase dissolution and kaolinite cementation occurred. This reaction occurred in relatively closed system due to the occurrence of kaolinite next to the site of plagioclase dissolution. Unaltered part of volcanic plagioclase and plutonic plagioclase which escaped albitization during maximum burial were preferentially dissolved to make plagioclase porosity. Secondary porosity resulting from dissolution of plagioclase and carbonate and anhydrite cements was mainly produced by formation waters containing organic acids released during atagenesis of organic matter.

• Journal of the Mineralogical Society of Korea
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• v.17 no.4
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• pp.327-338
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• 2004

XRD studies on annealed Na-feldspar (Amelia albite) at $1100^{\circ}C$ showed rapid structural changes due to Si-Al disordering, which resulted in phase transformations from low albite to high albite by 4-days annealing test. TEM SAED analyses on the annealed samples revealed a trend of structural changes, but estimation of the structural state was difficult due to a large deviation of the SAED data. Optimum conditions of CBED analyses on albite was established by employing a cooling specimen holder, 120 kV of acceleration voltage, 37 Jim of condenser aperture size and 25 nm of spot size. A proper orientation showing distinct changes of HOLZ lines corresponding to the structure changes of albite turned out to be close to the [418] direction with $-1.2^{\circ}$ tilting, where the width of two HOLZ lines in low albite was opposite to those in high albite.

• Annual Conference on Human and Language Technology
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• 1994.11a
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• pp.282-287
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• 1994

본 논문에서는 글자 단위를 기본으로 하는 한글 검색 기능을 구현할 때 적용될 수 있는 검색유형 (search pattern) 들은 어떠한 것들이 존재할 수 있는지에 대해 먼저 살펴보고, 검색 알고리즘에 적용시켜 본다. 이 때 부호계와의 연관성과 효율성을 따져보기 위해서 두 바이트 상용조합형, 두 바이트 KS C 5601 완성형, n-바이트 (3 바이트) 부호계, 그리고 국제 표준 한글 부호계의 첫-가-끝 부호계 등 여러가지 부호계를 사용할 때를 서로 비교해 본다. 각 부호계를 사용할 때 알고리즘이 조금씩 바뀌게된다. 그 변형을 살펴보면 그 효율을 측정할 수 있는데, 한글 글자단위 검색 등의 유형의 작업에서는 조합방식의 부호계를 사용하면 더욱 편리하다는 것을 알 수 있다. 이는 단순히 한글 글자단위 검색 기능에서 유리하다고 하기보다는 한글의 특성을 더 잘 반영하고 있다고 할 수 있는 것이다. 또한 조합방식의 부호체계 중에서도 별도의 연산값이 소리마디에서 글자를 분리해 낼 수 있는 부호계 (3-바이트 부호계, 첫-가-끝 부호계) 의 경우는 글자를 기본 단위로 처리하고자 하는 응용 분야에서 더욱 편리하게 사용될 수 있다.

• Proceedings of the Korea Multimedia Society Conference
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• 1998.10a
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• pp.20-25
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• 1998

본 논문은 자바의 성능을 분석하기 위한 것이다. 실행 중인 자바의 프로그램의 메쏘드에서 메쏘드가 속한 클래스, 바이트코드 정보와 메쏘드의 호출관계, 호출 횟수, 실행 시간, 메모리 사용에 관한 정보를 분석하여 시각화 도구를 통하여 그 결과를 쉽게 알 수 있도록 구현하였다. 자바 성능 분석기의 분석을 통하여 프로그램 개발자는 프로그램의 성능에 문제를 일으키는 부분을 개선시켜 보다 나은 성능의 프로그램 개발할 수 있다.

• Journal of the Mineralogical Society of Korea
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• v.26 no.4
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• pp.263-272
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• 2013

The Taebaegsan region and its vicinities mainly consist of Precambrian granitic gneisses and Cambrian meta-sedimentary rocks. And lots of leucocratic(alkali) granites smaller than the stocks are found here and there. Therefore the presence of leuco-granites is not properly described yet in the former studies. For the effective distinction of several granitic rocks, outcrop characteristics, mineral identification, and petro-chemical properties were studied. Some part of granitc gneisses could be classified into typical metamorphic rocks such as migmatites and banded gneisses. And some shows rather dark appearance with gray quartz and feldspars, and others two mica granites, leucocratic ones etc. But all of leucocratic granites of the region usually show bright milky white to beige color. Since they mainly consist of quartz, feldspars, muscovite, and small amounts of sericites, amphiboles, tourmaline and lepidolite. And all of alkali granites belong to the calc-alkalic, peraluminous and S-type in character. During magmatic differentiation of leucocratic granites, CaO and total Fe contents are clearly decreased than those of the older granitic rocks. On the other hand, magmatic evolution also had induced the greisenization and albitization which enriched the relative amounts of alkali elements such as $K_2O$ and $Na_2O$.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.11
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• pp.1741-1748
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• 2013

In this paper, we proposed new virtualization technology that is more convenient and stable in local computing environment, then found technique elements need to desktop virtualization which is based on clients in various virtualization technologies. After running excution of process explorer utility in user level virtualization and VMWare, we found memory capacity that is used 30.1MB in VMWare and 16.6MB in user level virtualization respectively to compare private bytes each of process. We found no significant difference of CPU utilization which is executed application program in local computing environment and user domain with user level virtualization. In this result, proposed virtualization technology is able to minimize performance degradation of local computing environment.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.1
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• pp.59-66
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• 2017

Hackers have obfuscated their malware to avoid being analyzed. Recently, obfuscation tools translate original codes into bytecodes to use virtualized-obfuscation, so that bytecodes are executed by virtual machines. In such cases, malware analysts fail to know about the malware before execution of the codes. We found that program slicing is one of promising program analysis techniques to solve this problem. The main concepts of program slice include slicing criteria given by analysts and sliced statements according to the slicing criteria. This paper proposes a deobfuscation method based on program slicing technique.

• The Journal of the Petrological Society of Korea
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• v.11 no.2
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• pp.90-102
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• 2002

The studied Fe-REE ore consists of magnetite, ankerite, siderite, magnesite and strontianite as the major constituent, and monazite, columbite, fergusonite, apatite, aegirine-augite, Na-amphibole, pyrite, chalcopyrite, sphalerite, molybdenite and barite as accessaries. Wall rock of ore deposits is replaced to fenite due to Na-metasomatism and mainly consists of sugary albite and Na-amphibole. Monazite $Ce_{0.49}La_{0.31}Pr_{0.14}Nd_{0.03}Gd_{0.03})PO_4$ is the main mineral for REE deposit and shows myrmekitic intergrowth with strontianite $Ca_{0.02-0.16}Sr_{0.84-0.98}CO_3$ and is corroded by carbonate minerals. Mineral forming sequence can be divided into early and late periods by the development of microfractures. The early period minerals such as magnetite, ankerite, magnesite, monazite and apatite show well developed networks of microfractures due to cataclastic deformation caused by enriched $CO_2$ gas in melts during emplacement. The late minerals of columbite, fergusonite, siderite molybdenite, chalcopyrite and sphalerite formed after the brecciation event and have little micro-fractures. Ankerite, magnesite, monazite, strontianite, barite and pyrite seem to be formed continuously from the ealy to the late period since they show textures both with well developed fractures and also with little fractures. Mineral chemistry, mineral assemblages such as various carbonate minerals, magnetite, REE minerals of monazite and fergusonite, Sr mineral of strontianite, and Nb minerals of columbite, myrmekitic texture of monazite and ankerite, and well developed fenite along ore deposits observed from this studied area strongly indicate that this Hongcheon Fe-REE ore deposits are formed from carbonatitic melt and its rock type is late differentiated Fe-carbonatite or ankerite-carbonatite.

• Mineral and Industry
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• v.17 no.1
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• pp.1-15
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• 2004

장석은 복잡다단한 광물학적 특성에도 불구하고 그 물질적 이해와 용도 측면에서의 단순성 때문에 관련 산업 부문에서 부가가치 향상이 잘 이루어지지 않고 있는 실정이다. 현재 전 세계적으로 10위권 내의 생산 수준을 유지하는 국내산 장석의 광석 유형은 그 관물상과 산출상태에 따라 페그마타이트상 장석, 반화강암질 및 우백질 화강암상의 장석으로 구분 될 수 있다. 현재 국내에서 개발되고 있는 장석들로는 일반적으로 반화강암질 유형의 광석이 가장 흔하다. 이 유형의 광체들은 흔히 알바이트화 작용이나 K-부화를 수반하는 열수변질 작용을 받은 양상을 보이는 것이 특징이다. 광물특성 상으로는 K-장석에 속하는 광체들이 Na-장석 유형들 보다 상대적으로 흔하고 대체적으로 그 부존 규모도 큰 것으로 나타난다. 장석의 부가가치 향상을 위해서는 그 품위를 화학조성에만 의존하지 말고 광물조성 단위로 이해하는 방식이 요구된다. 일반적으로 이 광물자원의 요업적 용도 특성상, 광물특성 평가에서 가장 주요한 기준이 되는 사항은 화학조성, 특히 알칼리 조성, $AI_{2}O_{3}$ 함량 및 철분의 함유도인 것으로 판단된다. 그렇지만 앞으로 그 수요가 확장될 전망이 있는 충진재 용도로 사용될 경우에는 이 같은 화학적 특징보다는 장석광물의 조성과 제반 물성적 특성에 그 품질이 의존될 것으로 여겨진다. 이에 따라 장석 광석의 화학조성과 물성은 기본적으로 장석의 광물상과 조성에 의존된다는 지식기반 하에서, 장석의 품위는 물론 품질 특성 평가에 있어서도 화학조성에만 의존하지 말고 그 광물상과 광물특성도 고려해서 평가하는 지혜가 요구된다.