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The New Finding on BOLD Response of Motor Acupoint KI6(照海) by fMRI (fMRI를 이용하여 수지굴신운동(手指屈伸運動)과 조해(照海)(KI6) 자침(刺鍼)에 의(依)한 대뇌운동피질(大腦運動皮質)의 활성변화(活性變化)에 관(關)한 비교(比較) 연구(硏究))

  • Kwon, Cheol-hyeon;Lee, Jun-beom;Hwang, Min-seob;Yoon, Jong-hwa
    • Journal of Acupuncture Research
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    • v.21 no.6
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    • pp.177-186
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    • 2004
  • Introduction : Recent studies Suggested that there is a strong correlation between acupuncture stimulation and its related cortical activation. Anther study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture stimulation. In ttis study, we investigated a new acupoint $KI_6$ (照海), which was known as motor-related acupoint and obtained an evidence that the stimulation of $KI_6$ resulted in either negative or positive BOLD response to stimulation. Methods & Results : 1. Subjects and paradigms : Two separate stimulation paradigms were performed on five healthy (aged 22-23 yrs) in this study. First, the paradigm of acupuncture stimulation was that the acupuncture needle was inserted in acupoints $KI_6$, which is located in lateral side of the foot and then continuously twisted(補瀉를 除外한 捻轉法) for 70 seconds for 10 cycles of activation. During rest period (70 seconds), the needle was completed removed from acupoint. Total 60 cycles were performed and 10 images were obtained per cycle. Second, nonacupoint was randomly selected and the same paradigm was performed as acupoint stimulation. The stimulation protocol comprised 10 cycles of alternating. activation and rest (10 images per cycle). Total 60 cycles were performed and each cycle take about 1.5 sec for motor task. Subjects take an at least 15 minutes break before starting anther paradigm. 2. fMRI mapping : Multi-slice functional images were obtained on a 1.5T Magnetom Vision MRI scanner (Simens Medical, Erlangen, Germany) equipped with high performance whole-body gradients. The BOLD T2 * - weighted images were acquired with acho planar imaging sequence (TR = 1.2 sec, TE = 60 msec, and flip angle = $90_{\circ}$). The other sequence parameter are : FOV = 210 mm, matrix=$64{\times}128$ or $64{\times}64$, slice number=10 and slice thickness = 5 or 8 mm. the anatomic images were obtained with Spin-echo T1-weighted images. The resulting images were then anaiyzed with STIMULATE (CMRR, U. of Minnesota) to generate functional maps using a student T-test (p < 0.005) and cluster analysis. Both positive and negative response were evaluated. Conclusions : We have observed the activation of the motor cortex by stimulating motor-related acupoint ($KI_6$). Among five subjects, negative BOLD response was shown in four and positive response in one. All subjects showed positive response to conventional finger flexion-extension task. To understand the detailed mechanisms of correlation between acupuncture stimulation and BOLD fMRI changes and two typs of response, further study strongly required.

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A Clustering Technique to Minimize Energy Consumption of Sensor networks by using Enhanced Genetic Algorithm (진보된 유전자 알고리즘 이용하여 센서 네트워크의 에너지 소모를 최소화하는 클러스터링 기법)

  • Seo, Hyun-Sik;Oh, Se-Jin;Lee, Chae-Woo
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.2
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    • pp.27-37
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    • 2009
  • Sensor nodes forming a sensor network have limited energy capacity such as small batteries and when these nodes are placed in a specific field, it is important to research minimizing sensor nodes' energy consumption because of difficulty in supplying additional energy for the sensor nodes. Clustering has been in the limelight as one of efficient techniques to reduce sensor nodes' energy consumption in sensor networks. However, energy saving results can vary greatly depending on election of cluster heads, the number and size of clusters and the distance among the sensor nodes. /This research has an aim to find the optimal set of clusters which can reduce sensor nodes' energy consumption. We use a Genetic Algorithm(GA), a stochastic search technique used in computing, to find optimal solutions. GA performs searching through evolution processes to find optimal clusters in terms of energy efficiency. Our results show that GA is more efficient than LEACH which is a clustering algorithm without evolution processes. The two-dimensional GA (2D-GA) proposed in this research can perform more efficient gene evolution than one-dimensional GA(1D-GA)by giving unique location information to each node existing in chromosomes. As a result, the 2D-GA can find rapidly and effectively optimal clusters to maximize lifetime of the sensor networks.

Association between Periodontitis and Coronary heart disease in Korea : Inflammatory markers and IL-1 gene polymorphism (한국인에서 치주질환과 관상동맥질환의 관련성에 대한 염증표지자와 IL-1 유전자 다변성의 영향)

  • Jeong, Ha-Na;Chung, Hyun-Ju;Kim, Ok-Su;Kim, Young-Joon;Kim, Ju-Han;Koh, Jung-Tae
    • Journal of Periodontal and Implant Science
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    • v.34 no.3
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    • pp.607-622
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    • 2004
  • Recently epidemiologic studies have indicated that the patients with periodontitis may have increased risk of ischemic cardiovascular events, and have suggested the important roles of blood cytokines and acute reactant proteins in the systemic infection and inflammatory response. Periodontitis and coronary heart disease (CHD) may share the common risk factors and the genetic mechanism associated with interleukin(IL)-1A, B and RA genotype may be involved in the production of IL-1. This study was aimed to investigate the relationship between angiographically defined CHD and periodontitis as chronic Gram-negative bacterial infection and to determine whether the IL-1 gene polymorphism is associated in both diseases. Patients under the age of 60 who had undergone diagnostic coronary angiography were enrolled in this study. Subjects were classified as positive CHD (+CHD, n=37) with coronary artery stenosis more than 50% in at least one of major epicardial arteries, and negative CHD (-CHD, n=30) without significant stenosis. After recording the number of missing teeth, periodontal disease severity was measured by means of plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), and radiographic bone loss around all remaining teeth. Gingival crevicular fluid (GCF) was collected from the 4 deepest periodontal pockets and assessed for cytokine ($IL-1{\beta}$, IL-6, IL-1ra, tumor necrosis $factor-{\alpha}$, and prostaglandin $E_2$). Additionally, blood CHD markers, lipid profile, and blood cytokines were analyzed. IL-1 gene cluster genotyping was performed by polymerase chain reaction and enzyme restriction using genomic DNA from buccal swab, and allele 2 frequencies of IL-1A(+4845), IL-1B(+3954), IL-B(-511), and IL-1RA(intron 2) were compared between groups. Even though there was no significant difference in the periodontal parameters between 2 groups, GCF level of $PGE_2$ was significantly higher in the +CHD group(p<0.05). Correlation analysis showed the positive relationship among PD, CAL and coronary artery stenosis(%) and blood $PGE_2$. There was also significant positive relationship between the periodontal parameters (PI, PD, CAL) and the blood CHD markers (leukocyte count, C-reactive protein, and lactic dehyrogenase). IL-1 gene genotyping showed that IL-1A(+3954) allele 2 frequency was significantly higher in the +CHD group compared with the -CHD group (15% vs. 3.3%, OR 5.118,p=0.043). These results suggested that periodontal inflammation is related to systemic blood cytokine and CHD markers, and contributes to cardiovascular disease via systemic inflammatory reaction. IL-1 gene polymorphism might have an influence on periodontal and coronary heart diseases in Korean patients.

Short-term changes of community structure of microbenthic invertebrates in the coastal waters Jeju Island, Korea from 2013 to 2015 (제주연안 저서무척추동물 군집구조의 단기변화 (2013-2015))

  • Ko, Jun-Cheol;Kim, Bo-Yeon;Sonh, Myoung-Ho;Jo, Woon-Chan;Lee, Kwan-Cheol
    • The Korean Journal of Malacology
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    • v.32 no.4
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    • pp.297-328
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    • 2016
  • This study was performed to know and compare the community structures of macrobenthic invertebrates of five fishing grounds in the coastal waters of Jeju Island from 2013 to 2015. A total of 629 species was identified. Molluscans comprised 282 species (44.8%), Arthropods 88 (14.0%), Poriferans 61 (9.7%), Bryozoans 52 (8.3%) and the others including Cnidarians 51 (8.1%). Density and biomass were estimated to be $71,007ind./m^2$ and $599,208.0gwwt/m^2$, respectively. Gastropods was the most dominant taxon in terms of abundance ($24,625ind./m^2$ ) and number of species as well, and Gastropods was predominant in biomass ($190,789.0gwwt/m^2$). The dominant species were Omphalius pfeifferi, Astralium haematragum, Musculus viridulus, Halosydna brevisetosa, Phascolosoma scolops, Herdmania monus in 5-20 m. Based on the cluster analysis, the study area could be divided into five station groups. The biodiversity, evenness and richness index appeared as follows: H' = 4.28-4.64, E' = 0.74-0.79, R = 33.17-35.45. The dominance index were highest in Sagye and lowest in Sinhung.

Utilization Behaviour and Influencing Factors of Complementary and Alternative Medicine Therapies Among the Elderly (일부 노인의 보완대체요법 이용행태와 영향요인)

  • Moon, Gi-Won;Kim, Jun-Ho;Kim, Chun-Bae
    • Journal of agricultural medicine and community health
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    • v.38 no.1
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    • pp.25-38
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    • 2013
  • Objectives: The aim of this study is to analyze the utilization behaviour and influencing factors of complementary and alternative medicine (CAM) therapies among elderly people with chronic diseases. Methods: The study population was selected among 9 welfare facilities for the aged in 2 cities among Daegu Metropolitan City & Gyeongsangnam Province by two-stage cluster sampling. 250 senior citizens participated in a face-to-face interview using a structured questionnaire. Logistic regression analysis was performed to examine the association between the utilization of CAM therapies and various characteristics of the elderly. All statistics were analyzed using the PASW (ver 18.0). Results: Among 233 elderly peoples, 70.4% (164 persons) had used various kinds of CAM therapies (including nutritional methods, pharmacologic and biologic treatments, etc.) more than once during the last year. 48.8% (64 persons) ~ 60.7% (88 persons) of the elderly used CAM therapies without health and medical experts' counsel. The elderly with perceptions of CAM therapy used it 2 times more than those without knowledge of CAM therapies. The number of chronic diseases was more likely to increase the usage of nutritional methods (OR=2.92, 95% CI: 1.07-7.97), manipulative and body-based practices (OR=5.85, 95% CI: 1.97-17.34), pharmacologic and biologic treatments (OR=2.92, 95% CI: 1.49-8.17). Elderly with diabetes used nutritional methods 3.76 (95% CI: 1.49-9.47) more than elderly without diabetes. Conclusions: CAM therapies use in the aged with chronic diseases appears common. The findings suggest that the clinical efficacy and safety of CAM therapies on medical management of chronic disease may be investigated and that patient-physician communication need to be strengthened.

An Energy Balanced Multi-Hop Routing Mechanism considering Link Error Rate in Wireless Sensor Networks (무선 센서 네트워크의 링크 에러율을 고려한 에너지소모가 균등한 멀티 홉 라우팅 기법)

  • Lee, Hyun-Seok;Heo, Jeong-Seok
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.6
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    • pp.29-36
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    • 2013
  • In wireless sensor networks, energy is the most important consideration because the lifetime of the sensor node is limited by battery. Most of the existing energy efficient routing protocols use the minimum energy path to minimize energy consumption, which causes an unbalanced distribution of residual energy among nodes. As a result, the power of nodes on energy efficient paths is quickly depletes resulting in inactive. To solve these problems, a method to equalize the energy consumption of the nodes has been proposed, but do not consider the link error rate in the wireless environment. In this paper, we propose a uniform energy consumption of cluster-based multi-hop routing mechanism considering the residual energy and the link error rate. This mechanism reduces energy consumption caused by unnecessary retransmissions and distributes traffic evenly over the network because considering the link error rate. The simulation results compared to other mechanisms, the proposed mechanism is energy-efficient by reducing the number of retransmissions and activation time of all nodes involved in the network has been extended by using the energy balanced path.

Construction of web-based Database for Haliotis SNP (웹기반 전복류 (Haliotis) SNP 데이터베이스 구축)

  • Jeong, Ji-Eun;Lee, Jae-Bong;Kang, Se-Won;Baek, Moon-Ki;Han, Yeon-Soo;Choi, Tae-Jin;Kang, Jung-Ha;Lee, Yong-Seok
    • The Korean Journal of Malacology
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    • v.26 no.2
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    • pp.185-188
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    • 2010
  • The Web-based the genus Haliotis SNP database was constructed on the basis of Intel Server Platform ZSS130 dual Xeon 3.2 GHz cpu and Linux-based (Cent OS) operating system. Haliotis related sequences (2,830 nucleotide sequences, 9,102 EST sequences) were downloaded through NCBI taxonomy browser. In order to eliminate vector sequences, we conducted vector masking step using cross match software with vector sequence database. In addition, poly-A tails were removed using Trimmest software from EMBOSS package. The processed sequences were clustered and assembled by TGICL package (TIGR tools) equipped with CAP3 software. A web-based interface (Haliotis SNP Database, http://www.haliotis.or.kr) was developed to enable optimal use of the clustered assemblies. The Clustering Res. menu shows the contig sequences from the clustering, the alignment results and sequences from each cluster. And also we can compare any sequences with Haliotis related sequences in BLAST menu. The search menu is equipped with its own search engine so that it is possible to search all of the information in the database using the name of a gene, accession number and/or species name. Taken together, the Web-based SNP database for Haliotis will be valuable to develop SNPs of Haliotis in the future.

Characteristics of Cities Types by Automobile Traffic Accidents (자동차 교통사고에 의한 도시유형의 특성)

  • Han, Ju-Seong
    • Journal of the Economic Geographical Society of Korea
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    • v.10 no.2
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    • pp.137-152
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    • 2007
  • This paper aims to clarify the types of cities by automobile traffic accidents and to search the characteristics of automobile traffic accidents for each type. Cities by automobile traffic accidents are classified into 4 types. Seoul city belongs to Type A in which 'automobile use and accident type' is closely related. Osan city belongs to Type B where the number of automobile traffic accidents is the greatest. And many satellite cities of Seoul city and metropolitan cities, and cities distributed in Southeastern industrial region belongs to Type C in which automobile accidents are fewer than the national average. Other 57 cities belongs to Type D which there are more automobile accidents than the national average. The cause of traffic accidents for each city type are as follows. In Seoul city the major causes of accidents are no security of safety distance, road patterns of other region, and injury of pedestrians. In Osan city, many single lane road accidents, central line invasion, and traffic accidents of children of under 14 years. And in satellite cities of Seoul city and metropolitan cities, and cities distributed in Southeastern industrial region, the major causes are traffic regulation violation, of under 6m in crossroad accidents, accident of children of under 14 years, and injury of pedestrians. Lastly, in other 57 cities chief causes are traffic regulation violation, wrong methods of passing crossroads, injury of children of under 14 and elderly of over 61 years, and injury of pedestrians.

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Top-down Hierarchical Clustering using Multidimensional Indexes (다차원 색인을 이용한 하향식 계층 클러스터링)

  • Hwang, Jae-Jun;Mun, Yang-Se;Hwang, Gyu-Yeong
    • Journal of KIISE:Databases
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    • v.29 no.5
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    • pp.367-380
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    • 2002
  • Due to recent increase in applications requiring huge amount of data such as spatial data analysis and image analysis, clustering on large databases has been actively studied. In a hierarchical clustering method, a tree representing hierarchical decomposition of the database is first created, and then, used for efficient clustering. Existing hierarchical clustering methods mainly adopted the bottom-up approach, which creates a tree from the bottom to the topmost level of the hierarchy. These bottom-up methods require at least one scan over the entire database in order to build the tree and need to search most nodes of the tree since the clustering algorithm starts from the leaf level. In this paper, we propose a novel top-down hierarchical clustering method that uses multidimensional indexes that are already maintained in most database applications. Generally, multidimensional indexes have the clustering property storing similar objects in the same (or adjacent) data pares. Using this property we can find adjacent objects without calculating distances among them. We first formally define the cluster based on the density of objects. For the definition, we propose the concept of the region contrast partition based on the density of the region. To speed up the clustering algorithm, we use the branch-and-bound algorithm. We propose the bounds and formally prove their correctness. Experimental results show that the proposed method is at least as effective in quality of clustering as BIRCH, a bottom-up hierarchical clustering method, while reducing the number of page accesses by up to 26~187 times depending on the size of the database. As a result, we believe that the proposed method significantly improves the clustering performance in large databases and is practically usable in various database applications.

Development of a Scalable Clustering A/V Server for the Internet Personal-Live Broadcasting (인터넷 개인 생방송을 위한 Scalable Clustering A/V Server 개발)

  • Lee, Sang-Moon;Kang, Sin-Jun;Min, Byung-Seok;Kim, Hag-Bae;Park, Jin-Bae
    • The KIPS Transactions:PartC
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    • v.9C no.1
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    • pp.107-114
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    • 2002
  • In these days, rapid advances of the computer system and the high speed network have made the multimedia services popularized among various applications and services in the internet. Internet live broadcasting, a part of multimedia services, makes it possible to provide not only existing broadcasting services including audio and video but also interactive communications which also expand application scopes by freeing from both temporal and spatial limitation. In the Paper, an interned Personal-live broadcasting server system is developed by allowing individual users to actively create or join live-broadcasting services with such basic multimedia devices as a PC camera and a sound card. As the number of broadcasters and participants increases, concurrent multiple channels are established and groups are to be expanded. The system should also guarantee High Availability (HA) for continuous services even in the presence of partial failure of the cluster. Furthermore, a transmission mode switching is supported to consider network environments in the user system.