• 한국광학회:학술대회논문집
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• 한국광학회 2005년도 하계학술발표회
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• pp.176-177
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• 2005

• 산업기술연구
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• 제11권
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• pp.99-106
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• 1991

In this paper the functional requirements of a B-ISDN access network based on MAN are investigated. Firstly, criteria of designing access network for the B-ISDN is studied. Secondly, the types of subscribers and their service requirements are defined. Thirdly, various architectures of CPNs(Customer Premises Networks) are considered and their characteristics are studied, Finally, the interworking functions of a DQDB MAN as an access network are investigated.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.36-39
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• 2004

Electrical impedance tomography (EIT) has been suffered from the severe ill-posedness which is caused by the inherent low sensitivity of boundary measurements to any changes of internal resistivity values. So, small noise occur unexpected reconstruction image. Generally in EIT system, if measured voltage includes noise, we can't find object location and resistivity values. In this paper, we propose digital filter for measured voltage in EIT. Newton-Raphson is the most..popular algorithm in EIT, but noise cause to blur image. We use Fourier transform (FT) in order to minimize the noise and design the filter. After filtering, result of reconstruction image is improved better than before filtering.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2005년도 학술대회
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• pp.87-90
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• 2005

이 연구는 DVB에서 제안한 휴대형 디지털 TV 전송시스템인 DVB-H 시스템의 이동수신 성능을 분석하였다. DVB-H 시스템은 DVB-T 시스템을 휴대용으로 보완한 것으로 4K 모드, MPE-FEC 및 In-depth Interleaver 등이 추가되었으며, 이 연구는 각 추가 기능에 대하여 이동수신 성능향상 정도를 분석하였다. 이동수신 환경을 제공하기 위하여 COST 207을 적용하였다. 4K 모드는 최대지연시간이 긴 다중경로채널에서 8K 모드와 유사하고 2K 모드보다 훨씬 우수한 수신성능을 보였으며 도플러에 대해서는 2K와 8K 모드의 중간정도의 수신성능을 보여 주었다. MPE-FEC와 In-depth Interleaver는 이동수신채널에서 약간의 수신성능 향상을 보여 주었다.

• 무역학회지
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• 제44권4호
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• pp.35-49
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• 2019

This study aims to determine whether the export volume of export country is affected by the strengthening of environmental management level of the importing country depending on the relative technology level of the importing country. To this end, a gravity model was established and the relative size of environmental management level was introduced, and how it affects the export was analyzed according to the difference of environmental management level between Korea and the importing country. The analysis of Korean industry by technology level (based on R&D investment) shows that countries with higher environmental management levels increase exports in both high and low technologies compared to Korea. On the other hand, exports of high-tech industries did not affect export growth in countries with lower environmental management than Korea.

• Biomolecules & Therapeutics
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• 제24권5호
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• pp.529-535
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• 2016

Atopic dermatitis (AD) results from gene and environment interactions that lead to a range of immunological abnormalities and breakdown of the skin barrier. Protease-activated receptor 2 (PAR2) belongs to a family of G-protein coupled receptors and is expressed in suprabasal layers of the epidermis. PAR2 is activated by both trypsin and a specific agonist peptide, SLIGKV-$NH_2$ and is involved in both epidermal permeability barrier homeostasis and epithelial inflammation. In this study, we investigated the effect of lobaric acid on inflammation, keratinocyte differentiation, and recovery of the skin barrier in hairless mice. Lobaric acid blocked trypsin-induced and SLIGKV-$NH_2$-induced PAR2 activation resulting in decreased mobilization of intracellular $Ca^{2+}$ in HaCaT keratinocytes. Lobaric acid reduced expression of interleukin-8 induced by SLIGKV-$NH_2$ and thymus and activation regulated chemokine (TARC) induced by tumor necrosis factor-a (TNF-${\alpha}$) and IFN-${\gamma}$ in HaCaT keratinocytes. Lobaric acid also blocked SLIGKV-$NH_2$-induced activation of ERK, which is a downstream signal of PAR2 in normal human keratinocytes (NHEKs). Treatment with SLIGKV-$NH_2$ downregulated expression of involucrin, a differentiation marker protein in HaCaT keratinocytes, and upregulated expression of involucrin, transglutamase1 and filaggrin in NHEKs. However, lobaric acid antagonized the effect of SLIGKV-$NH_2$ in HaCaT keratinocytes and NHEKs. Topical application of lobaric acid accelerated barrier recovery kinetics in a SKH-1 hairless mouse model. These results suggested that lobaric acid is a PAR2 antagonist and could be a possible therapeutic agent for atopic dermatitis.

• Journal of Acupuncture Research
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• 제20권1호
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• pp.228-235
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• 2003

Objective : Psoriasis is a common skin disease and the difficulty of its medical management is well known. This study was designed to investigate the effect of bee venom aqua-acupuncture on psoriasis. Methods : Bee venom aqua-acupuncture was performed two times a week. The following points were selected: LI-11(曲池), LI-15, K-9(築賓) on both sides of body. For herbal medicine, YanHyulJiHwangTang-gami was given. We checked involvement in plaque, erythematous popules and invasiveness according to psoriasis area severity index(PASI). Results :After 9 weeks of treatment, the patient showed that itching symptoms was disappeared and score of PASI changed from 26.2 to 0. Conclusions : These results suggest that bee venom aqua-acupuncture and herbal medicine has good effect on psoriasis. But further studies are required to concretely prove the effectiveness of bee venom aqua-acupuncture for treating psoriasis.

• Biomolecules & Therapeutics
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• 제25권5호
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• pp.528-534
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• 2017

Placenta is a special organ that contains many nutrients such as growth factors, minerals, and bioactive peptides. Dipeptides of glycine and leucine are major components of porcine placenta extracts (PPE) that has been used as an alternative of human placenta extracts. In this study, we investigated whether major peptides of PPE, Glycyl-L-Leucine (Gly-Leu), L-Leucyl-Glycine (Leu-Gly), and L-Leucyl-L-Leucine (Leu-Leu), affect skin hydration and elasticity in vitro and in vivo. We found that Gly-Leu and Leu-Gly dipeptides induced the expression of transglutaminase 1 in normal human epidermal keratinocytes (NHEKs) whereas Leu-Leu dipeptides did not. Treatment with Gly-Leu or Leu-Gly significantly increased hyaluronan (HA) synthesis in NHEKs and the upregulation of hyaluronan synthase 2 (HAS2) mRNA level was confirmed. In addition, elastase activity was inhibited in NHEKs treated with Gly-Leu or Leu-Gly dipeptides. Oral administration of Gly-Leu or Leu-Gly dipeptides increased skin hydration and elasticity in UVB-irradiated hairless mice. The significant upregulation of HA in UVB-irradiated hairless mice was observed in response to oral administration of Gly-Leu or Leu-Gly. These results suggest that the major dipeptides of porcine placenta, Gly-Leu and Leu-Gly, are potentially active ingredients for skin moisturization formulations.

• 한국정보처리학회논문지
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• 제7권6호
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• pp.1867-1873
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• 2000

함수근사는 과학과 고학부야에서 공범위하게 응용된다. 시포트 벡터 기계(support vector machine, SVM)는 원래 분류를 위해 계안되어져 문자인식, 얼굴인식 등의 응용분야에서 좋은 결과를 보여주고 있다. 최근 SVM이론 함수근사로 확장되어 많이 활용되려 하고 있다. 그러나 함수근사를 위한 SVM 알고리즘은 QP(quadratic proramming)문제와 관련되어있어 계산에 시간이 걸리며 QP를 위한 패키지가 있어야 한다. 본 논문에서는 함수근사를 위해 커널-애더트론 알고리즘을 이용한 SVM을 제안하고 QP를 이용한 SVM과 성능을 비교하고자 한다.

• Communications for Statistical Applications and Methods
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• 제18권2호
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• pp.165-170
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• 2011

Support vector quantile regression(SVQR) is capable of providing a good description of the linear and nonlinear relationships among random variables. In this paper we propose a sparse SVQR to overcome a limitation of SVQR, nonsparsity. The asymmetric e-insensitive loss function is used to efficiently provide sparsity. The experimental results are presented to illustrate the performance of the proposed method by comparing it with nonsparse SVQR.