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Energy-Aware Routing Protocol for Mobile Ad Hoc Network (노드의 여유 에너지 기반 이동 Ad Hoc 네트워크의 라우팅 프로토콜)

  • Kwon, Soo-Kun
    • Journal of Korea Multimedia Society
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    • v.8 no.8
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    • pp.1108-1118
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    • 2005
  • A mobile Ad Hoc network is a dynamic mobile wireless network that can be formed without the need for any pre-existing wired or wireless infrastructure. A mobile ad hoc node has limited battery capacity. Hence, Ad Hoc routing protocol ought to be energy conservative. Previous energy aware routing has limit in fairness among nodes and network wide power consumption. In this research, we propose a new routing protocol called Clustering Based Energy-Aware Routing(CBEAR) which can improve the problems. Simulation results show that the routing protocol improves fairness and network wide power consumption as well as life time of nodes.

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Anti-bacterial and Anti-inflammatory Effects of Angelica dahurica Extracts in Helicobacter pylori-infected Human Gastric Epithelial AGS Cells (백지(Angelica dahurica) 추출물의 Helicobacter pylori에 대한 항균력 및 H. pylori로 유도한 염증반응에 대한 항염 효과)

  • Choi, Min Kyeong;Yim, Dongsool;Choi, SungSook
    • Korean Journal of Pharmacognosy
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    • v.49 no.3
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    • pp.255-261
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    • 2018
  • The aim of this study was to evaluate the anti-helicobacter activity and anti-inflammatory activity of Angelica dahurica (AD). The minimum inhibitory concentration(MIC) of AD against Helicobacter pylori(H. pylori), expression of the H. pylori cagA gene in the presence of AD was determined. Inhibition of H. pylori urease by AD, inhibition of nitric oxide (NO) production in AGS cells was measured. IL-8 mRNA expression in AGS cells which were infected with H. pylori and IL-8 level was measured. The MIC of MeOH Ex. of AD was $250{\mu}g/mL$ and the expression of cagA gene was decreased about 88% in the presence of AD. The activity of H. pylori urease was inhibited 70% by AD. mRNA expression of IL-8 and the production of NO and IL-8 were significantly decreased in the presence of AD. In conclusion, AD showed anti-Helicobacter activity and has potent anti-inflammatory effect on H. pylori-induced inflammation in human gastric epithelial AGS cells.

Mechanism of Authentication Procedure between Ad Hoc Network and Sensor Network (에드 홉 네트워크와 개별 센서 네트워크 간의 인증 절차 메카니즘)

  • Kim, Seungmin;Yang, Jisoo;Kim, Hankyu;Kim, Jung Tae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.160-161
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    • 2013
  • Extending mobile IP to ad hoc networks with the foreign agent acting as the bridge between the wired network and ad hoc networks can provide the global Internet connectivity for ad hoc hosts. The existing research in the area of the integrated wired and ad hoc network is carried out in a non-adversarial setting. This paper analysed an effective solution to solve the security related problems encountered in these integrated networks. This security protocol also excludes malicious nodes from performing the ad hoc network routing. This paper focuses on preventing ad hoc hosts from the attacks of anti-integrity.

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Message Complexity Analysis of TDMA Ad-hoc Network MAC Protocols (TDMA Ad-hoc 네트워크 MAC 프로토콜의 메시지 복잡도 분석)

  • Kim, Sang-Chul
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.8B
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    • pp.768-776
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    • 2009
  • This paper analyses the message complexity of TDMA ad hoc MAC protocols. Since the network resource of ad hoc networks is limited due to the multiple interferences and the contention-based wireless channel, the scalability issue is one of the main research topics in developing ad hoc algorithms. Simulation demonstrates that SMACS protocol has the lowest message complexity, whereas TMMAC has the highest. In addition, it is found that since the effect of unicast dominates in the message complexity compared to other factors with an increasing number of nodes, Z-MAC tends to have the property of linearity, whereas BMA and TMMAC show exponential increases in their complexities.

Peripheral inflammatory biomarkers in Alzheimer's disease: a brief review

  • Park, Jong-Chan;Han, Sun-Ho;Mook-Jung, Inhee
    • BMB Reports
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    • v.53 no.1
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    • pp.10-19
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    • 2020
  • Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain. The AD pathophysiology entails chronic inflammation involving innate immune cells including microglia, astrocytes, and other peripheral blood cells. Inflammatory mediators such as cytokines and complements are also linked to AD pathogenesis. Despite increasing evidence supporting the association between abnormal inflammation and AD, no well-established inflammatory biomarkers are currently available for AD. Since many reports have shown that abnormal inflammation precedes the outbreak of the disease, non-invasive and readily available peripheral inflammatory biomarkers should be considered as possible biomarkers for early diagnosis of AD. In this minireview, we introduce the peripheral biomarker candidates related to abnormal inflammation in AD and discuss their possible molecular mechanisms. Furthermore, we also summarize the current state of inflammatory biomarker research in clinical practice and molecular diagnostics. We believe this review will provide new insights into biomarker candidates for the early diagnosis of AD with systemic relevance to inflammation during AD pathogenesis.

Secure Routing Protocol in Cluster-Based Ad Hoc Networks (클러스터 기반 애드혹 네트워크 환경에서의 보안 라우팅 프로토콜)

  • Min, Sung-Geun;Park, Yo-Han;Park, Young-Ho;Moon, Sang-Jae
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37C no.12
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    • pp.1256-1262
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    • 2012
  • Mobile ad hoc networks (MANETs) are infrastructure-less, autonomous, and stand-alone wireless networks with dynamic topologies. Recently, cluster-based ad hoc networks which enhance the security and efficiency of ad hoc networks are being actively researched. And routing protocols for cluster-based ad hoc networks are also studied. However, there are few studies about secure routing protocols in cluster-based ad hoc networks. In this paper, we propose secure routing protocol for cluster-based ad hoc networks. We use Diffie-Hellman key agreement, HMAC, and digital signature to support integrity of routing messages, and finally can perform secure routing.

The Effects of Chinese Consumers' Self-Construal and Advertising Type on Brand Attitude

  • Choi, Nak-Hwan;Liu, Huan;Li, Zhonghua
    • Asian Journal of Business Environment
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    • v.8 no.3
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    • pp.33-41
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    • 2018
  • Purpose - This study focused on the attitude differences towards harmony-focused Ad and uniqueness-focused Ad, also those towards brand advertised in each of the two type Ads between self-construals. Research design, data, and methodology - Main survey was conducted online with the people in China, and collected 107 data through harmony Ad questionnaire and 109 data through uniqueness Ad questionnaire. Anova and t-test were used to verify hypotheses. Results - First, More positive attitude towards harmony-focused Ad and the brand in it there was at interdependent Chinese consumers than at independent Chinese consumers. Second, the independent Chinese consumers and the interdependent Chinese consumers did not form significant attitude difference towards uniqueness-focused Ad. However the independent Chinese consumers showed more positive attitude towards the brand in the uniqueness-focused Ad than the interdependent Chinese consumers. Conclusions - By highlighting the attributes of Chinese consumers' self-construal, to appeal to interdependent Chinese consumers, marketers should develop harmony-focused advertisement, and they should appeal to independent Chinese consumers by using uniqueness-focused advertisement. However the harmony might be pursued as the main content in the overall environment by Chinese people. Therefore it is necessary for the marketers to consider the harmony even when appealing them by emphasizing the uniqueness.

Diagnosis of Alzheimer's Disease using Combined Feature Selection Method

  • Faisal, Fazal Ur Rehman;Khatri, Uttam;Kwon, Goo-Rak
    • Journal of Korea Multimedia Society
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    • v.24 no.5
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    • pp.667-675
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    • 2021
  • The treatments for symptoms of Alzheimer's disease are being provided and for the early diagnosis several researches are undergoing. In this regard, by using T1-weighted images several classification techniques had been proposed to distinguish among AD, MCI, and Healthy Control (HC) patients. In this paper, we also used some traditional Machine Learning (ML) approaches in order to diagnose the AD. This paper consists of an improvised feature selection method which is used to reduce the model complexity which accounted an issue while utilizing the ML approaches. In our presented work, combination of subcortical and cortical features of 308 subjects of ADNI dataset has been used to diagnose AD using structural magnetic resonance (sMRI) images. Three classification experiments were performed: binary classification. i.e., AD vs eMCI, AD vs lMCI, and AD vs HC. Proposed Feature Selection method consist of a combination of Principal Component Analysis and Recursive Feature Elimination method that has been used to reduce the dimension size and selection of best features simultaneously. Experiment on the dataset demonstrated that SVM is best suited for the AD vs lMCI, AD vs HC, and AD vs eMCI classification with the accuracy of 95.83%, 97.83%, and 97.87% respectively.

A Review on the Correlation between the Pathology of Alzheimer's Disease and microRNA

  • Kim, Soo-Jung;Cho, Hyun-Jeong
    • Biomedical Science Letters
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    • v.27 no.4
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    • pp.208-215
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    • 2021
  • The purpose of this study was to explain the pathology of Alzheimer's disease (AD) and to investigate the correlation between AD and microRNA. AD is the most common type of dementia, accounting for about 80% of all types of dementia, causing dysfunction in various daily activities such as memory loss, cognitive impairment, and behavioral impairment. The typical pathology of AD is explained by the accumulation of beta-amyloid peptide plaques and neurofibrillary tangles containing hyperphosphorylated tau protein. On the other hand, microRNA is small non-coding RNA 22~23 nucleotides in length that binds to the 3' untranslated region of messenger RNA to inhibit gene expression. Many reports explain that microRNAs found in circulating biofluids are abundant in the central nervous system, are involved in the pathogenic mechanism of AD, and act as important factors for early diagnosis and therapeutic agents of AD. Therefore, this paper aims to clarify the correlation between AD and microRNA. In this review, the basic mechanism of miRNAs is described, and the regulation of miRNAs in the pathological processes of AD are highlighted. Furthermore, we suggest that miRNA-based system in development of therapeutic and diagnostic agents of AD can be a promising tool.

Changes in Chemical Properties and Effect on Germination of Radish Seed from Aeration of Co-digestate Fertilizers (통합 혐기소화액별 폭기처리에 따른 화학적 성분 변화와 무의 발아효과)

  • Byeon, Ji-Eun;Lee, Hong-Ju;Ryoo, Jong-Won;Hwang, Sun-Goo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.65 no.4
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    • pp.508-517
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    • 2020
  • This study aimed to determine the minimum period of aeration treatment of co-digestate to develop it as liquid fertilizer and the chemical changes that occur in the aerobic liquefying process. The co-digestates were divided into three types depending on their additives: swine slurry anaerobic digestate (SS AD), swine slurry 70% + cow slurry 30% anaerobic digestate (SS + CS AD), and swine slurry 70% + apple pomace 30% anaerobic digestate (SS + AP AD). The pH of all co-digestates increased rapidly after 3 days of aerobic treatment, but had slightly decreased in SS AD after 9 days and in SS + CS AD and SS + AP AD after 15 days. All co-digestates showed a strongly reduced pH between 27 and 36 days of aeration treatment. SS AD had lower pH value, dissolved oxygen (DO), NH4-N, and NO3-N content under aerobic conditions than other co-digestates. To assess the fully decomposed liquid fertilizer, a germination test was performed on the undiluted and diluted co-digestate using the liquid fertilizer germination index (LFGI) method. The relative germination ratio, relative root elongation, and germination index of SS AD were higher than those of the others. When the LFGI method was used for the germination test, all co-digestates showed an appropriate germination index of 70 after 60 days of aeration treatment. Thus, we suggest that the minimum period of aeration treatment for co-digestates might be 60 days to develop the fully decomposed liquid fertilizer.