• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.1
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• pp.23-27
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• 2003

Structural properties of Cu-Ni alloy films, such as preferred orientation, crystallite size, in-ter-planar spacing, cross-sectional morphology, and electrical resistivity, are investigated in terms of tar-get configurations that are used in the film deposition by means of magnetron co-sputtering. Two different target configurations are considered in this study: a dual-type configuration in which two separate tar-gets (Cu and Ni) and different bias types (RF and DC) are used and a Ni-on-Cu type configuration in which Ni chips are attached to a Cu target. The dual-type configuration appears to have some advantages over the Ni-on-Cu type regarding the accurate control of atomic composition of the deposited Cu-Ni alloy. However, the dual-type-produced film exhibits a porous and columnar structure, the relatively large internal stress, and the high electrical resistivity, which are mainly due to the relatively low mobility of adatoms. The affects of thermal treatment and deposition conditions on the structural and electrical properties of dual-type Cu-Ni films are also discussed.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.117-118
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• 2011

초경합금 위에 RF Magnetron Sputter를 이용하여 Ti 중간층을 증착 후 MPECVD(Microwave Plasma Enhanced Chemical Vapor Deposition) 시스템을 이용하여 나노결정 다이아몬드 박막을 증착 하였다. 공정압력, 마이크로웨이브 전력, Ar/$CH_4$ 조성비, 기판온도를 일정하게 놓고 직류 bias의 인가 여부를 변수로 하고 증착시간을 0.5, 1, 2시간으로 변화시켜 박막을 제작하였다. 제작된 시편은 FE-SEM과 AFM을 이용하여 다이아몬드 박막의 표면과 다이아몬드 박막의 표면 거칠기 등을 측정하였고, Raman spectroscopy와 XRD를 이용하여 다이아몬드 결정성을 확인하였다. Automatic Scratch �岵謙�ter를 이용하여 복합박막의 층별 접합력을 측정하였다. 바이어스를 인가하지 않고 다이아몬드 박막을 증착할 경우 증착 시간이 증가할수록 다이아몬드 입자의 평균 크기가 증가하며 입자들이 차지하는 면적이 증가하는 것을 확인하였다. 그러나 1시간이 경과해도 아직 완전한 박막은 형성되지 못하고 2시간 이상 증착 시 완전한 박막을 이루는 것이 확인되었다. 이에 비해서 바이어스 전압을 인가할 경우 1시간 내에 완전한 박막을 이루었다. 표면 거칠기는 바이어스를 인가한 경우가 그렇지 않은 경우에 비해서 조금 높은 것으로 나타났다. 이러한 바이어스 효과는 표면에서의 핵생성 밀도 증가와 재핵생성 속도 증가에 기인하는 것으로 해석된다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.8
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• pp.1782-1789
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• 1997

Most systems that retrieve distributed information on the Internet have difficulties in retrieving relevant information for they are not able to reflect exact semantics on retrieval queries that usersrequest. In this paepr, we propose an automatic query expansion based on ter distribution which reflects semantics of retrieval term to emhance the performance of information retrieval. We computed weight, indicating its overal imoritance in the collection documents and user's query and we use LSI's SVD technique to measure the term distribution which appears similar to query. And also, we measure the similarity to compared numerical value with query terms. Also we researched the method to reduce additional terms automatically and evaluated the performance of the proposed method.

• Environmental Analysis Health and Toxicology
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• v.17 no.3
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• pp.239-243
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• 2002

Changes of plasma vitellogenin (VTG) and glutamate pyruvate transaminase (GPT) were examined for determining whether hepatocyte was damaged during the process of VTG induction in the juvenile rockfish, Sebastes schlegeli exposed to exogenous estrogen (estradiol-l7$\beta$, E$_2$). Rockfishes were intraperitoneally injected with E$_2$(5 mg/kg B.W.) in 70% ethanol and plasma sampling were extracted at 0, 1, 3, 6, 9, 12, 15 days af-ter E$_2$administration. VTG and GPT were then analyzed by SDS -PAGE and Reitman -Frankel method, respectively. VTG band was detected at a molecular weight position of 175 kDa on Day 3 after E$_2$administration. This band became more distinct at 6 days, but its was gradually thinned with time -course, and not detected at 15 days. GPT was suddenly increased at 1 days after 22 administration and highest GPT was detected at 3 days. However. GPT was gradually decreased with time -course as the change of VTG. These results suggest that the process of VTG induction by exogenous E$_2$damage to hepatocyte, and plasma GPT was temporarily increased in the juvenile rockfish.

• Radiation Oncology Journal
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• v.7 no.2
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• pp.157-169
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• 1989

Radiological and clinical evidences indicate that hyperthermia combined with irradiation produce a significant improvement in therapeutic effect of cancer The experiences obtained from 90 rats' kidney A single dose of irradiation ranged from 6Gy, 8Gy and 10Gy was delivered on the rat's kidney. The combined therapy group had the same irradiation after hyperthermia at $42\~44^{\circ}C$ for 30 minutes. Microscopic examination and calculation of thermal enhancement ratio were carried out, and the results were as follows: 1. In the group of hyperthermia alone, there were moderate glomerular congestion and mild tubular degeneration on light microscopic examination. 2. In the group of irradiation alone, tubular degeneration was noted in 6Gy irradiation and its severity was increased along with radiation dose. 3. In the group of hyperthermia combined with irradiation, tubular degeneration and necrosis were appeared in 6Gy and 10Gy irradiation, respectively. 4. On electron microscopic examination, proximal convoluted tubular and glomerular changes in irradiation group were similar to that of combined with hyperthermia, and its severity was increased along with observation periods. 5. Thermal enhancement ratio (TER) was 1.0 after evaluation of histipathologic changes in rat's kidney, with combination therapy.

• Korean Journal of Microbiology
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• v.23 no.4
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• pp.265-270
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• 1985

Overall procedure of cell fusion between Brevibacterium flavum and Corynebacterium glutamicum was morphologically observed by transmission electron microscopy. Protoplasts formed by treatment of cells with penicillin G and lysozyme in order were released through the pores generated on a certain region of cell walls to be spherical form. When two different protoplasts were met, cell wall and membrane in the contact zone was disappeared and followed by the mutual exchange of cytoplasmic and/or chromosomal materials. Cell xall regeneration speed of the protoplasts fused was slower than that of the non-fused, whereas the size of the former was confirmed as bigger than that of the latter.

• Molecules and Cells
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• v.26 no.4
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• pp.329-337
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• 2008

Src-family kinases are critically involved in the control of cytoskeleton organization and in the generation of integrin-dependent signaling responses, inducing tyrosine phosphorylation of many signaling and cytoskeletal proteins. Activity of the Src family of tyrosine kinases is tightly controlled by inhibitory phosphorylation of a carboxy-terminal tyrosine residue, inducing an inactive conformation through binding with its SH2 domain. Dephosphorylation of C-ter tyrosine, as well as its deletion of substitution with phenylalanine in oncogenic Src kinases, leads to autophosphorylation at a tyrosine in the activation loop, thereby leading to enhanced Src activity. Beside this phophorylation/dephosphorylation circuitry, cysteine oxidation has been recently reported as a further mechanism of enzyme activation. Mounting evidence describes Src activation via its redox regulation as a key outcome in several circumstances, including growth factor and cytokines signaling, integrin-mediated cell adhesion and motility, membrane receptor cross-talk as well in cell transformation and tumor progression. Among the plethora of data involving Src kinase in physiological and pathophysiological processes, this review will give emphasis to the redox component of the regulation of this master kinase.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.387-396
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• 1999

Dog meat was begun to be edible by the Chinese, Japanese, the French, Belginan, German Philippines Vietnamese, North-Americans African-Indians Canadian-aborigines Alaskan aborigines including Kor-eans. According to the record, Korea has a long history to have eaten dog meat from the era of Sam-kug(three kingdoms BC 57∼AC 668) and so there are numerous languages proverbs, and customs re-lated to the dog meat. Over the long history there have been many records and recipes about the edib-leness of dog meat. But at present time only the way of cooking such as Bosintang(a soup) Suyuk(a boiled meat) Duruchighi(boiled meat added spice and slightly roasted) Muchim(boiled meat added by spice and mixed) Gaesoju(an extract) Jeongol(boiled meat mixed with spices vegetables and water on the pot) remains. Koreans eat dog meat following the traditional customs n the Boknal(hottest day in summer). Also the areas of Buyo. Sochon, Boryong adn Chongyang of Chungnam province and the ad-jacent areas like Kongju, Iksan, and Nonsan have customs to kill the dog and offer dog meat to the gue-sts in time of small or big occasions such as funeral ceremony Hoigap(anniversary of one's 60th birth-day) and one's birthday. This range of customs is expanding larger and larger. These areas are the cen-ter of past Baekche(BC 57∼AC 660). In spite of this it is unreasonable, and excessive action for foreig-ner to fine fault with the dog meat or Korean food culture.

• Journal of the Korean institute of surface engineering
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• v.26 no.4
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• pp.192-202
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• 1993

The characteristics of the high-performance ceramic coatings fabricated on the optimum processings con-ditions for the atmospheric plasma spraying are evaluated by various material tests and analyses. The opti-mum processing parameters for the plasma spraying are determined by using the two-level orthogonal arrays of fractional factorial testing method as a statistical approach. Material tests for the coating specimens are carried out to evaluate microstructure, hardness, adhesion strength, and deposition efficiency. The properties of Al2O3-13%TiO2 coating are discussed with regard to the effective processings parameters. The decarburization effects of WC-12%Co coating is examined by XRD analysis in terms of the arc power and the secondary gas species. The hardness of Al2O2-13%TiO2 coating is increased with the arc power and shows the maximum value at around 40 lpm of Ar gas flowrate, which appears to be the most critical parame-ter on the deposition efficiency. For reducing the decarburization of WC-12%Co coating, the injection of inert He gas instead of reactive H2 gas as a secondary gas is more effective than the dropping of arc power to lessen the plasma enthalpy.

• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.923-928
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• 2000

[FeIII(BBA)DBC]ClO4 as a new functional model for catechol dioxygenases has been synthesized, where BBA is a bis(benzimidazolyl-2-methyl)amine and DBC is a 3,5-di-tert-butylcatecholate dianion.The BBA complex has a structuralfeature that iron cent er has a five-coordinate geometry similar to that of catechol dioxygenase-substrate complex.The BBA complex exhibits strong absorptionbands at 560 and 820 nm in CH3CN which are assigned to catecholate to Fe(III) charge transfer transitions. It also exhibits EPR signals at g = 9.3 and 4.3 which are typical values for the high-spin FeIII (S = 5/2) complex with rhombicsymmetry. Interestingly, the BBA complex reacts with O2 within an hour to afford intradiol cleavage (35%) and extradiol cleavage (60%) products. Surprisingly, a green color intermediate is observed during the oxygenation process of the BBA com-plex in CH3CN. This green intermediate shows a broad isotropic EPR signal at g = 2.0. Based on the variable temperature EPR study, this isotropic signalmight be originated from the [Fe(III)-peroxo-catecholate] species havinglow-spin FeIII center, not from the simple organic radical. Consequently,it allows O2 to bind to iron cen-ter forming the Fe(III)-superoxide species that converts to the Fe(III)-peroxide intermediate. These present data can lead us tosuggest that the oxygen activation mechanism take place for the oxidative cleavingcatechols of the five-coordinate model systems for catechol dioxygenases.