• International Journal of Contents
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• 제7권2호
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• pp.6-10
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• 2011

The directional MAC (DMAC) protocol improves the spatial reuse, but directional packets on the control channel cause the deafness problem. In this paper, we propose a tone dual-channel DMAC protocol for mobile ad-hoc networks. In the proposed MAC protocol, the use of omnidirectional transmissions using an omnidirectional out-of-band tone solves the deafness problem and decrease packet collisions on the control channel. The use of an omnidirectional out-of-band tone also mitigates the hidden terminal problem. We use the negative CTS (NCTS) mechanism to solve the exposed terminal problem. The throughput performance of the proposed MAC protocol is confirmed by simulations using the Qualnet simulator.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (A)
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• pp.52-54
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• 2004

Ad-hoc 네트워크는 기존의 유선 네트워크와 달리 여러 가지 제약을 갖고 있다. 그 중에서 가장 큰 제약은 배터리에 저장된 한정된 에너지에 의존해서 동작한다는 것이다. 어떤 모바일 노드가 배터리에 저장된 에너지를 모두 소비하게 되면, 그 노드는 더 이상 네트워크에 참여할 수 없게 된다. 이러한 현상이 증가하게 되면 네트워크가 두 개 이상의 서브 네트워크로 분할되는 문제가 발생할 수 있다. 이러한 문제를 해결하기 위해서 라우팅을 통하여 에너지 소비를 좀 더 효율적으로 네트워크로 분산시키기 위한 RDRP(Request Delay Routing Protocol)와 MMRP(Max Min Routing Protocol) 프로토콜들이 제안되었다. 본 논문에서는 에너지 상태에 따라 플러딩(Flooding)을 지연시키는 RDRP 방법에 현재 형성된 라우팅 경로까지 함께 고려한 EP-AODV(AODV considering Energy and Path)를 제안한다. 또한, NS-2(Network Simulator 2) 시뮬레이터를 이용한 성능 평가를 통하여 본 논문에서 제안된 프로토콜이 좀 더 에너지 소비를 네트워크 전체로 효율적으로 분산시킨다는 것을 보일 것이다.

• 경영과정보연구
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• 제14권
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• pp.215-234
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• 2004

The objectives of this study are to examine what are the important promotion activities and images when students choose the university. In order to this research, 277 students drawn from university in pusan area are utilized and 5 hypotheses are analyzed by t-test, anova and regression analysis. The principal findings of empirical study are as follows (1) the most important promotion activities are ranked as follows 1) advice from other peoples(family and teacher are ranked highly) 2) publicity 3) university brochure 4) guide magazine for university 5) university homepage etc. Against our expectation, TV (radio) ad. transit ad. newspaper ad. are ranked lowly among the factors. (2) this study reveals that the most important university images are possibility of good job employment and future growth, confidence, ability of research and lecture, specialization of major etc. but history and tradition, scale of uni. are ranked lowly among the factors. (3) this study reveals that seven universities those are analyzed have different images. In order to achieve the more effective promotion strategy, universities may strengthen their good images and make better their weak images. I have a conviction that the findings above can be applicable for university promotion strategy.

• BMB Reports
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• 제42권8호
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• pp.475-481
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• 2009

Emerging data demonstrate pivotal roles for brain insulin resistance and insulin deficiency as mediators of cognitive impairment and neurodegeneration, particularly Alzheimer's disease (AD). Insulin and insulin-like growth factors (IGFs) regulate neuronal survival, energy metabolism, and plasticity, which are required for learning and memory. Hence, endogenous brain-specific impairments in insulin and IGF signaling account for the majority of AD-associated abnormalities. However, a second major mechanism of cognitive impairment has been linked to obesity and Type 2 diabetes (T2DM). Human and experimental animal studies revealed that neurodegeneration associated with peripheral insulin resistance is likely effectuated via a liver-brain axis whereby toxic lipids, including ceramides, cross the blood brain barrier and cause brain insulin resistance, oxidative stress, neuro-inflammation, and cell death. In essence, there are dual mechanisms of brain insulin resistance leading to AD-type neurodegeneration: one mediated by endogenous, CNS factors; and the other, peripheral insulin resistance with excess cytotoxic ceramide production.

• Journal of Ginseng Research
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• 제35권2호
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• pp.149-154
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• 2011

In order to determine the efficacy of functional foods, objective measurement of the severity of atopic dermatitis (AD) after taking foods is important. The aim of this study was to conduct an objective evaluation of whether Korean red ginseng (KRG) might be helpful for improvement of skin condition and serum IgE in patients with AD. Thirty atopic patients (18 females and 12 males) participated in this study. Patients took KRG for 16 weeks. Bioengineering methods, including the corneometer and evaporimeter, were used at the start of the study and after 8 weeks and 16 weeks. In addition, we assessed serum IgE levels and the severity scoring of the atopic dermatitis (SCORAD) index. Transepidermal water loss and skin hydration showed significant improvement after 16 weeks. A significant decrease in the SCORAD index, as well as in serum IgE level, was observed after 16 weeks. Our results demonstrated that KRG may be helpful as a functional food for patients with AD.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2002년도 춘계학술발표논문집 (하)
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• pp.1591-1594
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• 2002

이 논문에서는 기존의 Ad Hoc 네트워크 라우팅 방법 중 proactive routing 과 reactive routing 의 장점을 접목시켜 2-tier 계층구조위에서 효율적인 routing 기법을 제안한다. 또한 제한된 tier-2 네트워크에서 기존의 3GPP 서비스와 상호 연동 가능성을 고려하여 네트워크의 형태 변화에 따른 클러스터 헤더의 효율적인 생성 및 안정적인 경로 확보와 함께 클러스터 헤더의 신뢰성을 제공하기 위한 키 분배 메커니즘을 고찰한다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2012년도 춘계학술발표대회
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• pp.481-484
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• 2012

차로에서 차량의 많은 증가는 안전과 무선통신의 가용성에 대한 필요성을 높여 왔다. Vehicular ad hoc networks(VANETs)은 다양한 차량 어플리케이션을 위한 용도와 상용분야로의 개발을 점차적으로 해오고 있다. 차량 간의 효과적인 통신범위를 제공하기 위해서 최적화된 라우팅 프로토콜이 필요하다. 지금까지 목적지까지 최적의 경로를 찾는 mobile ad hoc networks(MANETs)를 위한 많은 기존의 프로토콜들이 존재한다. 본 논문에서는 두 개의 라우팅 프로토콜들을 비교함으로써 VANET 환경을 위한 프로토콜 개선방향을 제시하였다. Multicast Ad-hoc On-Demand Distance Vector(MAODV)[1][2] 라우팅 프로토콜의 솔루션은 목적지 대상으로 최적의 경로를 탐색함으로써 더욱 향상된 결과를 보여준다. NS-2[3]는 라우팅 프로토콜 실험을 수행하고 결과를 도출하는데 사용되어 왔다. 실험을 통하여 최적의 라우팅 프로토콜에 대한 연구방향 및 개선될 사항을 찾고자 한다.

• 대한의생명과학회지
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• 제24권4호
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• pp.305-310
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• 2018

Microglia are emerging as critical regulators of innate immune responses in AD and other neurodegenerative disorders, highlighting the importance of understanding their molecular and cellular mechanisms. We attempted to determine the role of crosstalk signaling between $IFN-{\gamma}$ and $TGF-{\beta}$ in $A{\beta}$ clearance by microglia cells. We used in vitro and in vivo mouse models that recapitulated acute and chronic aspects of microglial responses to $A{\beta}$ peptides. We showed that crosstalk signaling between $TGF-{\beta}$ and Smad2 was an important mediator of neuro-inflammation. These findings suggest that microglial $TGF-{\beta}$ activity enhances the pathological progression to AD. As $TGF-{\beta}$ displays broad regulatory effects on beneficial microglial functions, the activation of inflammatory crosstalk signaling between $TGF-{\beta}$ and Smad2 may be a promising strategy to restore microglial functions, halt the progression of $A{\beta}$-driven pathology, and prevent AD development.

• Journal of Multimedia Information System
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• 제6권2호
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• pp.87-90
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• 2019

Machine learning techniques have been applied in almost all the domains of human life to aid and enhance the problem solving capabilities of the system. The field of medical science has improved to a greater extent with the advent and application of these techniques. Efficient expert systems using various soft computing techniques like artificial neural network, Fuzzy Logic, Genetic algorithm, Hybrid system, etc. are being developed to equip medical practitioner with better and effective diagnosing capabilities. In this paper, a comparative study to evaluate the predictive performance of subtractive clustering based ANFIS hybrid system (SCANFIS) with Fuzzy C-Means (FCM) based ANFIS system (FCMANFIS) for Alzheimer disease (AD) has been taken. To evaluate the performance of these two systems, three parameters i.e. root mean square error (RMSE), prediction accuracy and precision are implemented. Experimental results demonstrated that the FCMANFIS model produce better results when compared to SCANFIS model in predictive analysis of Alzheimer disease (AD).

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.291.2-291.2
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• 2002

For the safety evaluation of adenovirus-mediated gene therapy. we have investigated gene and protein expression after transduction of adenoviral vector (Ad5CMV-p16) which contains tumor suppressor gene. p161NK4$\alpha$ in human non-small cell lung cancer (A549) cells. We compared the differential gene expression level in the A549 cells treated with Ad5CMV (null type) and Ad5CMV-p16 virus. respectively. by using cDNA membrane chip and oligonucleotide chip. (omitted)