• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.189-197
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• 2017

This paper elaborates two novel proposed topologies (type-I and type-II) of the high step-up DC-DC converter using switched inductor and voltage multiplier cell. The advantages of these proposed topologies are the less voltage stress on semiconductor devices, low device count, high power conversion efficiency, high switch utilization factor and high diode utilization factor. We analyze the Type-II topologies operating principle and mathematical analysis in detail in continuous conduction mode. High-intensity discharge lamp for the automotive application can use the derived topologies. The proposed converters give better performance when compared to the existing types. Also, it is found that the proposed type-II converter has relatively higher voltage gain compared to the type-I converter. A 40 W, 12 V input voltage and 72 V output voltage has developed for the type-II converter and the performances are validated.

• Journal of Food Hygiene and Safety
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• v.2 no.4
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• pp.191-196
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• 1987

Erythrosine used as a colouring agent in drugs, cosmetics and foods in Korea, was examined for its effects on murine immune system and methemoglobin formation. As immunotoxicologic assay parameters, we adopted circulating leukocytes and immunoorgan weights for pathotoxicology, IgM plaque forming cells and arthus reaction for humoral immunity, delayed hypersensitivity reaction of cell mediated immunity and carbon clearacnce for macrophage function. Erythrosine's effects were observed as follows; 1. Ery throsine showed no significant effects on circulating leulocyte counts and relative immunoorgan weight. 2. Erythrosine diminished IgM plaque forming cells. 3. Erythrosine decreased arthus reaction, in the dose dependent manner. 4. Erythrosine had no significant effect on delayed hypersensitivity. 5. Phagocytic and corrected phagocytic index were not affected. 6. Methemoglobin content was similar in the test and control groups.

• Journal of applied mathematics & informatics
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• v.33 no.5_6
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• pp.559-578
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• 2015

Human Immune Deficiency Virus (or simply HIV) induces a persistent infection that leads to AIDS causing death in almost every infected individual. As HIV affects the immune system directly by attacking the CD4+ T cells, to exterminate the infection, the natural immune system produces virus-specific cytotoxic T lymphocytes(CTLs) that kills the infected CD4+ T cells. The reduced CD4+ T cell count produce reduced amount of cytokines to stimulate the production of CTLs to fight the invaders that weakens the body immunity succeeding to AIDS. In this paper, we introduce a mathematical model with discrete time-delay to represent this cell dynamics between CD4+ T cells and the CTLs under HIV infection. A modified functional form has been considered to describe the infection mechanism. Characteristics of the system are studied through mathematical analysis. Numerical simulations are carried out to illustrate the analytical findings.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.83-83
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• 2002

This study was to compare the characteristics of parthenogenetic mES (P-mES) cells and in vitro fertilization mES cells. Mouse oocytes were recovered from superovulated 4wks hybrid F1 (C57BL/6xCBA/N) female mice. The oocytes were treated with 7% ethanol for 5 min and 5 ㎍/㎖ cytochalasin-B for 4 h. For IVF, the oocytes were inseminated with epididymal sperm of hybrid Fl male mice (1×10/sup 6//㎖). IVF and parthenogenetic embryos were cultured in M16 medium for 4 days. Cell number count in blastocysts was carried out differential labelling using propidium iodide (red) and bisbenzimide(blue). (omitted)

• Proceedings of the Korea Multimedia Society Conference
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• 1998.10a
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• pp.243-247
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• 1998

전자현미경 영상인 유방암 조직세포의 암 분포 정도를 알기 위해, 조직세포중 암이 퍼진 부분과 그렇지 않은 부분에 대해 정량적 분석과 세포수에 의한 분석을 비교하여 보았다. 유방암 조직세포의 면역조직화함염색에서 암이 있는 세포핵은 갈색으로 나타났고, 그렇지 않은 세포는 푸른색으로 나타났다. 이것은 환자를 진단하고 예지하는데 있어서 중요한 요인으로 작용하지만 지금까지는 의사의 주관적인 생각이 다분히 포함된 판단에 의존할 수 밖에 없었다. 의료영상이미지의 시각적 표현을 위해 RGB칼라를 HLS칼라로 변환하여 사용하였으며, 이것은 시각적으로 좀 더 쉽게 갈색세포핵과 푸픈색 세포핵을 구분하게 해 주었다. 두 세포핵을 분리하기 위해 히스트그램의 임계치와 Box classification의 두 알고리즘의 사용하여 추출하였다. 그리고 추출한 세포핵들에 대해 각각 정량적인 분석과 세포수에 의한 분석을 하였다. 이러한 실험은 시각적 병리정밀검사에 좋은 보조도구로 사용될 수 있을 것이다.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2699-2701
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• 2005

최근에 인상적으로 건강한 CD4 T 세포의 수치를 기준으로 약물의 투여 여부를 결정하는 STI 치료 기법이 제안되었다. 본 논문에서는 수학적 생물학 관점에서 이 치료 방법의 유효성을 알아보고, 환자의 면역 시스템을 분석한다. CD4 T 세포의 수치가 고려된 STI 기법은 기존에 제시된 STI 방법과 비교하여 치료기간과 약물 투여량을 각각 감소시켰고, 환자를 LTNP의 상태로 치료하였다. 또한, CD4 T 세포의 수치를 기준으로 약물 투여 여부를 결정하는 방법이 CTLp의 수치를 증가시키는 것과도 관련이 있음을 확인하였다.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.82-85
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• 1998

Because ATM was originally designed for the optical fiber environment with bit error rate(BER) of 10-11, it is difficult to maintain ATM cell extraction capability in wireless environment where BER ranges from 10-6 to 10-3. Therefore, it must be proposed the algorithm of ATM cell extraction in wereless environment. In this paper, the frame structure and synchronization algorithm satisfyling the above condition are explained, and the new ASIC implementation method of this algorithm is proposed. The known method using shift register needs so many gates that it is not suitable for ASIC implementation. But in the proposed method, a considerable reduction in gate count can be achieved by using random access memory.

• Journal of Oral Medicine and Pain
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• v.12 no.1
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• pp.17-26
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• 1987

In order to investigate the biostimulatory effect of low power density laser radiation in vitro, human gingival fibroblasts were cultured in MEM in which experiment groups respectively were made to 30 sec, 60 sec and 90 sec group. The experiments were performed by cell count, DNA and protein content measurements after experimental groups were irradiated with GaAlAs laser every day by forth day and then control group and experimental groups were compared. The results were as follows: 1. Cell counts of experimental groups were increased with exposure time, but showed no significance (P>0.05). 2. When the protein contents were compared, there was a very significant increase in 90 sec. experimental group (P<0.01). 3. When the DNA contents were compared, there was a significant difference only between control and 70 sec. group (P<0.05).

• Advances in Traditional Medicine
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• v.5 no.1
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• pp.48-56
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• 2005

We studied the protective effect of Echinacea purpurea against radiation by evaluating changes in the peripheral blood cell count and peripheral blood antioxidant activity. Echinacea purpurea administration had a suppressive effect on radiation-induced leukopenia, especially on lymphocytes and monocytes and resulted in a faster recovery of blood cell counts. Mouse peripheral blood antioxidant activity was increased by Echinacea purpurea, and a relationship between the suppressive effect on radiation-induced leukopenia and the antioxidant effect was suggested.

• Journal of Korea Foundry Society
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• v.32 no.5
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• pp.211-218
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• 2012

The effects of thickness, silicon and manganese contents on the mechanical properties of 3.3 wt%C-0.1 wt%S thin-section gray cast iron plates were investigated. The eutectic cell counts and volume fraction of pearlite in the matrix decreased with increased thickness and therefore the strength and hardness decreased with it. Even though the eutectic cell count increased with increased silicon content, the volume fraction of pearlite decreased and the strength and hardness decreased with it. The pearlite was refined more with increased manganese content and therefore the strength and hardness increased with it.