• 센서학회지
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• 제25권5호
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• pp.337-343
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• 2016

In this paper, we newly introduce a wireless identification system using a solar cell and RF transceivers. The reader sends interrogating signal to a transponder using LED visible light, and the transponder responds to the reader using RF signal. The transponder consists of a solar cell, an amplifier, a microprocessor, and an RF transmitter. The solar cell receives the visible light from the reader and generates current to supply electric power to the other devices in the transponder. At the same time, the solar cell detects interrogating signal in the reader light. The microprocessor senses the interrogating signal and generates a responding signal. The RF transmitter radiates the responding signal to the reader. The transponder is a passive circuit because it operates without external power. In experiments, the maximum read distance between a reader and a transponder was about 1.6 meter.

• 대한교통학회지
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• 제20권5호
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• pp.193-206
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• 2002

신호교차로로 구성된 네트워크의 시스템최적 신호시간산정을 위해 Cell Transmission 이론을 교통류 모형으로 활용한 신호최적화 모형을 제안한다. Cell Transmission 모형은 기존에 소개된 신호최적화 모형과는 달리 충격파, 대기행렬의 길이, 그리고 하류부 교차로 대기행렬의 역류(Spillback)과 같은 과포화 현상을 표현하는데 적절한 이론적이고 실제적인 배경을 지원한다. 모형에서 기점을 출발한 수요차량은 종점에 도착할 때까지 경로선택을 통해서, 그리고 신호시스템은 이러한 수요의 움직임 고려하여 신호시간요소의 최적화를 통한 네트워크의 비용을 최소화하기 위해 서로 협력한다는 의미에서 제안된 모형은 시스템 최적화를 의미한다. 모형은 혼합정수계획법으로 정식화되며 최적신호전략과 고정신호전략간의 실험계획을 통해 구축된 모형을 비교·평가한다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권1호
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• pp.52-55
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• 2002

Flow cytometric techniques were used to investigate cell size, protein content and cell cycle behavior of recombinant Saccharomyces cerevisiae strains producing human lysozyme (HLZ). Two different signal sequences, the native yeast $MF\alpha1$ signal sequence and the rat $\alpha-amylase$ signal sequence, were used for secretion of HLZ. The strain containing the rat $\alpha-amylase$ signal sequence showed a higher level of internal lysozyme and lower specific growth rates. Flow cytometric analysis of the total protein content and cell size showed the strain harboring the native yeast signal sequence had a higher total protein content than the strain containing the rat $\alpha-amylase$ signal sequence. Cell cycle analysis indicated that the two lysozyme producing recombinant strains had an increased number of cells in the $G_2+M$ phase of the yeast cell cycle compared with the host strain SEY2102.

• Biomolecules & Therapeutics
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• 제7권4호
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• pp.329-334
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• 1999

Recently, cellular signal transduction mechanisms are greatly understood. However, bone cell signaling is not completely characterized. Interestingly, bone cells synthesize a number of growth factors such as IGF-I PDGF, IGF-II etc., suggesting these growth factors play important roles in bone cell signaling. In the present study, potential roles of nitric oxide (NO) and protein kinases in osteoblast signal transduction are proposed.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 1998년도 제38회 춘계학술발표대회
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• pp.49.1-49.1
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• 1998

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.27-30
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• 2004

OFDMA is considered as one of the major candidates for broadband wireless access. The OFDMA signal is usually coherently demodulated, requiring the channel estimation which can be estimated using a known pilot signal. In multi-cell environment, the performance of channel estimation is mainly limited by intercell interference. It is desirable to use a pilot signal that can estimate the channel information robust to the intercell interference in the OFDMA uplink system. In this paper, we consider two types of pilot signal applicable to multi-cell OFDMA uplink systems: One is time-multiplexed pilot signal and the other is code­multiplexed pilot signal. Simulation results show that the code-multiplexed pilot is suitable for low mobility environment and time-multiplexed pilot is suitable for high mobility environment.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9791-9795
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• 2014

To study the gene expression change and possible signal pathway during androgen-dependent prostate cancer (ADPC) becoming androgen-independent prostate cancer (AIPC), an LNCaP cell model of AIPC was established using flutamide in combination with androgen-free environment inducement, and differential expression genes were screened by microarray. Then the biological process, molecular function and KEGG pathway of differential expression genes are analyzed by Molecule Annotation System (MAS). By comparison of 12,207 expression genes, 347 expression genes were acquired, of which 156 were up-ragulated and 191 down-regulated. After analyzing the biological process and molecule function of differential expression genes, these genes are found to play crucial roles in cell proliferation, differntiation, cell cycle control, protein metabolism and modification and other biological process, serve as signal molecules, enzymes, peptide hormones, cytokines, cytoskeletal proteins and adhesion molecules. The analysis of KEGG show that the relevant genes of AIPC transformation participate in glutathione metabolism, cell cycle, P53 signal pathway, cytochrome P450 metabolism, Hedgehog signal pathway, MAPK signal pathway, adipocytokines signal pathway, PPAR signal pathway, TGF-${\beta}$ signal pathway and JAK-STAT signal pathway. In conclusion, during the process of ADPC becoming AIPC, it is not only one specific gene or pathway, but multiple genes and pathways that change. The findings above lay the foundation for study of AIPC mechanism and development of AIPC targeting drugs.

• 한국광학회지
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• 제29권6호
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• pp.247-252
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• 2018

본 논문에서는 200 mW 이하의 낮은 펌핑 조건의 다이오드 펌프 세슘 증기 셀에서 약한 신호광 증폭을 보고한다. 고효율 증폭효과를 얻기 위해서 펌프빔과 신호빔을 하나의 단일 모드 광섬유로 통과시켜 세슘 증기 셀 내부에서 완전히 겹치도록 하였다. 우리는 약한 신호광의 증폭 정도를 셀의 온도, 신호광의 세기, 펌프광의 세기에 따라 조사하였다. 증기 셀의 온도 $115^{\circ}C$, 신호광의 출력 0.1 mW, 그리고 펌프광의 출력 200 mW인 조건에서 56배의 증폭효과를 얻을 수 있었다.

• Archives of Pharmacal Research
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• 제25권1호
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• pp.1-10
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• 2002

Attempts to develop drugs, specific for cancer cells, are dealt here according to the intended cell-target. While many target specific drugs were developed, they reach only moderate successes in clinics for reasons, such as, delivery problem, lack of in vivo efficacy or toxicity. However, recent efforts focusing on the diversity of tyrosine kinases, participating in cell-signal transduction, brought fruit. The first such drug, Givec, approved by the USFDA recently, is used in clinics with great success to threat CML. The drug inhibits tyrosin kinase of bcr-abl, c-abl and v-abl. Work is progressing on other tyrosin kinase inhibitors and on other type of specific cancer cell signal protein inhibitors. These efforts are hoped to yield better cures for cancer in the near future.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2020년도 하계학술대회
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• pp.593-595
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• 2020

본 논문에서는 5G NR 시스템을 위한 동기 신호를 이용한 cell ID 검출 방법에 대한 성능을 비교하였다. 5G NR(fifth-generation new radio) 시스템의 송신기는 SS/PBCH (synchronization signal/physical broadcast channel) 블록을 송신하며, 수신기는 수신된 SS/PBCH 블록을 이용하여 주파수 및 타이밍 오프셋 (frequency and timing offset)을 추정 할 수 있으며, cell ID (cell identity)는 PSS (primary synchronization signal)와 SSS (secondary synchronization signal)를 통해 검출할 수 있다. 본 논문에서는 cell ID 를 검출할 수 있는 방법으로서 2-stage 디코딩 방법과 결합 최대우도 결정 규칙 (joint maximum-likelihood decision rule: joint ML) 디코딩 방법을 사용하였다. Joint ML 디코딩 방법은 2-stage 디코딩 방법에 비해 더 좋은 검출 성능을 보이지만, 복잡도 측면에서는 2-stage 디코딩 방법이 joint ML 디코딩 방법에 비해 더 낮은 복잡도를 갖는 것을 확인하였다.