• 한국콘텐츠학회논문지
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• 제11권4호
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• pp.273-282
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• 2011

본 연구는 국소 허혈성 뇌손상 흰쥐 모델에서 tDCS의 자극 적용시간을 달리하였을 때, 앞다리 운동감각 기능변화와 신경영양인자(GAP-43)발현에 미치는 영향을 알아보고자 하였다. 뇌손상 모델은 Sprague -Dawley계 흰쥐 80마리를 'Longa'방법을 이용하여 중대뇌동맥(middle cerebral artery)을 폐색하여 유발하였고, 실험군을 4개로 나누었다; 실험군I은 허혈성 뇌손상 유발군(n=20), 실험군II는 허혈성 뇌손상 유발 후 tDCS(10분) 적용군(n=20), 실험군III은 허혈성 뇌손상 유발 후 tDCS(20분) 적용군(n=20), 실험군IV는 허혈성 뇌손상 유발 후 tDCS(30분) 적용군(n=20)으로 나누었다. 앞다리운동감각 기능검사를 위해 수정된 앞다리배치 검사와 단일 팰릿 닿기 검사를 실시하였으며, 신경가소성에 대한 면역조직화학적 검사로 운동감각 영역에서의 GAP-43 단백질 발현을 관찰하였다. 앞다리운동감각 검사는 14일에서 실험군III (p<0.05)이 다른 군들에 비해 유의한 차이를 보였으며, 단일 팰릿 닿기 검사는 14일에서 실험군III(p<0.01)과 실험군IV(p<0.05)에서 유의한 차이를 보였다. 또한, 면역조직학적 검사는 14일에 실험군III이 다른 군들에 비해 현저한 면역양성반응의 증가를 보였다. 따라서, 0.1 mA의 강도로 20분간 적용했을 때가 앞다리운동감각 기능과 신경가역성 인자 GAP-43 발현에 가장 좋은 조건임을 알 수 있었다.

• Journal of Ginseng Research
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• 제39권1호
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• pp.29-37
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• 2015

Background: Panax ginseng (i.e., ginseng) root is extensively used in traditional oriental medicine. It is a modern pharmaceutical reagent for preventing various human diseases such as cancer. Ginsenosidesd-the major active components of ginsengd-exhibit immunomodulatory effects. However, the mechanism and function underlying such effects are not fully elucidated, especially in human monocytes and dendritic cells (DCs). Methods: We investigated the immunomodulatory effect of ginsenosides from Panax ginseng root on $CD14^+$ monocytes purified from human adult peripheral blood mononuclear cells (PBMCs) and on their differentiation into DCs that affect $CD4^+$ T cell activity. Results: After treatment with ginsenoside fractions, monocyte levels of tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and IL-10 increased through phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and c-Jun N-terminal kinase (JNK), but not p38 mitogen-activated protein kinase (MAPK). After treatment with ginsenoside fractions, TNF-${\alpha}$ production and phosphorylation of ERK1/2 and JNK decreased in lipopolysaccharide (LPS)-sensitized monocytes.We confirmed that DCs derived from $CD14^+$ monocytes in the presence of ginsenoside fractions (Gin-DCs) contained decreased levels of the costimulatory molecules CD80 and CD86. The expression of these costimulatory molecules decreased in LPS-treated DCs exposed to ginsenoside fractions, compared to their expression in LPS-treated DCs in the absence of ginsenoside fractions. Furthermore, LPS-treated Gin-DCs could not induce proliferation and interferon gamma (IFN-${\gamma}$) production by $CD4^+$ T cells with the coculture of Gin-DCs with $CD4^+$ T cells. Conclusion: These results suggest that ginsenoside fractions from the ginseng root suppress cytokine production and maturation of LPS-treated DCs and downregulate $CD4^+$ T cells.

• 한국컴퓨터정보학회지
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• 제14권2호
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• pp.129-134
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• 2006

이 논문에서는 터미널 부분의 중요 신호를 유무선방식을 통하여 통합적으로 감시, 관리하기 위한 DCS 터미널 원격 감시 미들웨어를 설계 및 구현하고 미들웨어의 성능 및 기능을 평가하기 위해 터미널 부분의 릴레이들의 동작 상태 및 퓨즈의 이상 유무를 실시간으로 감시하기 위한 보드를 설계 제작한다. 제안된 DCS 터미널 원격감시 미들웨어는 각 릴레이들의 동작 상태를 실시간으로 확인이 가능하며 에러 발생 시 에러 유형을 즉시 제공하며 또한 릴레이의 규격 및 사용기간을 고려하여 교체시기를 알려주어 릴레이의 고장을 사전에 예방함으로써 산업분야의 경제적인 효과가 기대된다.

• 한국ITS학회 논문지
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• 제4권1호
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• pp.89-95
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• 2005

본 논문에서는 GSM/GPS/DCS/US-PCS 핸드 셋을 위한 4중 대역 안테나를 제안한다. 제안되어진 안테나는 핸드 셋의 제한된 내부 공간에 집적하기 위하여 저자세로 설계되어 지고 ,다중대역을 위해 $\lambda$/4 길이를 갖는 세 개의 방사점으로 구성된다. 또한 안테나의 크기 변화 없이 넓은 대역폭을 얻기 위하여 방사체 아래의 접지면을 제거하였고, GPS/DCS/US-PCS 대역의 편리한 임피던스 매칭을 위하여 방사체 중앙에 슬릿을 추가하였다. 제안되어진 안테나는 전 대역에서 VSWR 3:1 대역폭을 만족하고, anechoic chamber (10m$\times$6m$\times$4m)내의 측정 결과 전 대역에서 최대 이득은 -2.19 dB 에서 2.09 dB이다

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.294-298
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• 2003

In this paper, the modeling and design of high-Q multilayer passives have been investigated, and multilayer diplexer for GSM/DCS applications has been designed and fabricated using the passives. To minimize the system, the configuration of a multilayer inductor has involved a square spiral structure. Modeling of a multilayer inductor was performed by the subsystems of distributed components, and using the modeling the optimal structures of the high-Q multilayer inductor could be designed by analyzing parasitics and couplings which affect their frequency characteristics. Multilayer diplexer for GSM/DCS application has been designed and fabricated using LTCC technology. LPF for GSM band had the passband insertion loss of less than 0.55 dB, the return loss of more than 12 dB, and the isolation level of more than 26 dB by locating attenuation pole at 1800 MHz. HPF for DCS band had the passband insertion loss of less than 0.82 dB, the return loss of more than 11 dB, and the isolation level of more than 38 dB by locating attenuation pole at 930 MHz.

• Smart Structures and Systems
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• 제3권4호
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• pp.455-474
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• 2007

A flexibility-based distributed computing strategy (DCS) for structural health monitoring (SHM) has recently been proposed which is suitable for implementation on a network of densely distributed smart sensors. This approach uses a hierarchical strategy in which adjacent smart sensors are grouped together to form sensor communities. A flexibility-based damage detection method is employed to evaluate the condition of the local elements within the communities by utilizing only locally measured information. The damage detection results in these communities are then communicated with the surrounding communities and sent back to a central station. Structural health monitoring can be done without relying on central data acquisition and processing. The main purpose of this paper is to experimentally verify this flexibility-based DCS approach using wired sensors; such verification is essential prior to implementation on a smart sensor platform. The damage locating vector method that forms foundation of the DCS approach is briefly reviewed, followed by an overview of the DCS approach. This flexibility-based approach is then experimentally verified employing a 5.6 m long three-dimensional truss structure. To simulate damage in the structure, the original truss members are replaced by ones with a reduced cross section. Both single and multiple damage scenarios are studied. Experimental results show that the DCS approach can successfully detect the damage at local elements using only locally measured information.

• Journal of Information Processing Systems
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• 제16권2호
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• pp.261-276
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• 2020

Digital contents services are one of the topics that have been intensively studied in the media industry, where various semantic and ontology techniques are applied. However, query execution for ontology data is still inefficient, lack of sufficient extensible definitions for node relationships, and there is no specific semantic method fit for media data representation. In order to make the machine understand digital contents (DCs) data well, we analyze DCs data, including static data and dynamic data, and use ontology to specify and classify objects and the events of the particular objects. Then the formal representation method is proposed which not only redefines DCs data based on the technology of OWL/RDF, but is also combined with media segmentation methods. At the same time, to speed up the access mechanism of DCs data stored under the persistent database, an ontology-based DCs query solution is proposed, which uses the specified distance vector associated to a surveillance of semantic label (annotation) to detect and track a moving or static object.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권2호
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• pp.608-627
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• 2016

Wireless mesh networks (WMNs) based on IEEE 802.11s have emerged as one of the prominent technologies in multi-hop communications. However, the deployment of WMNs suffers from serious interference problem which severely limits the system capacity. Using multiple radios for each mesh router over multiple channels, the interference can be reduced and improve system capacity. Nevertheless, interference cannot be completely eliminated due to the limited number of available channels. An effective approach to mitigate interference is to apply dynamic channel switching (DCS) in WMNs. Conventional DCS schemes trigger channel switching if interference is detected or exceeds a predefined threshold which might cause unnecessary channel switching and long protocol overheads. In this paper, a P-learning based dynamic switching algorithm known as learning automaton (LA)-based DCS algorithm is proposed. Initially, an optimal channel for communicating node pairs is determined through the learning process. Then, a novel switching metric is introduced in our LA-based DCS algorithm to avoid unnecessary initialization of channel switching. Hence, the proposed LA-based DCS algorithm enables each pair of communicating mesh nodes to communicate over the least loaded channels and consequently improve network performance.

• IMMUNE NETWORK
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• 제11권6호
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• pp.399-405
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• 2011

Background: Endogenous uveitis is a chronic inflammatory eye disease of human, which frequently leads to blindness. Experimental autoimmune uveoretinitis (EAU) is an animal disease model of human endogenous uveitis and can be induced in susceptible animals by immunization with retinal antigens. EAU resembles the key immunological characteristics of human disease in that both are $CD4^+$ T-cell mediated diseases. Dendritic cells (DCs) are specialized antigen-presenting cells that are uniquely capable of activating naive T cells. Regulation of immune responses through modulation of DCs has thus been tried extensively. Recently our group reported that donor strain-derived immature DC pretreatment successfully controlled the adverse immune response during allogeneic transplantation. Methods: EAU was induced by immunization with human interphotoreceptor retinoid-binding protein (IRBP) $peptide_{1-20}$. Dendritic cells were differentiated from bone marrow in the presence of recombinant GM-CSF. Results: In this study, we used paraformaldehyde-fixed bone marrow-derived DCs to maintain them in an immature state. Pretreatment with fixed immature DCs, but not fixed mature DCs, ameliorated the disease progression of EAU by inhibiting uveitogenic $CD4^+$ T cell activation and differentiation. Conclusion: Application of iBMDC prepared according to the protocol of this study would provide an important treatment modality for the autoimmune diseases and transplantation rejection.

• 대한통합의학회지
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• 제7권3호
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• pp.33-40
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• 2019

Purpose : The purpose of this randomized controlled trial study was to examine the effect of transcranial direct current stimulation (tDCS) on cognitive function and depression in stroke patients. Methods : Thirty stroke patients were randomly divided into an experimental group (n = 15) and a control group (n = 15). The experimental group received tDCS while performing computerized cognitive rehabilitation programs, and the control group was provided with sham tDCS while operating the same programs. The 30-minute intervention was implemented five times per week for six weeks. To assess cognitive function before and after the intervention, the Neurobehavioral Cognitive Status Examination was conducted; the Beck Depression Inventory BDI was employed to assess depression. Results : The experimental group showed statistically significant increases in cognitive function and decreases in depression (p < .05 ). Comparing the amount of variation between the groups after arbitration also showed significant differences in cognitive function and depression between the two groups (p > .05). Conclusion : The application of tDCS and computerized cognitive rehabilitation programs for stroke patients may positively affect their cognitive function and depression. Therefore, tDCS used with computerized cognitive rehabilitation programs is positively applicable to the enhancement of cognitive function in stroke patients and reduction of depression.