• Title/Summary/Keyword: Data Clustering

Search Result 2,747, Processing Time 0.034 seconds

A New Routing Algorithm for Performance improvement of Wireless Sensor Networks (무선 센서 네트워크의 성능 향상을 위한 새로운 라우팅 알고리즘)

  • Yang, Hyun-Suk;Kim, Do-Hyung;Park, Joon-Yeol;Lee, Tae-Bong
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.49 no.1
    • /
    • pp.39-45
    • /
    • 2012
  • In this paper, a distributed 2-hop routing algorithm is proposed. The main purpose of the proposed algorithm is to reduce the overall power consumption of each sensor node so that the lifetime of WSN(wireless sensor network) is prolonged. At the beginning of each round, the base station transmits a synchronization signal that contains information on the priority table that is used to decide whether each sensor node is elected as a cluster head or not. The priority table is constructed so that sensor nodes closer to half energy distance from the base station get the higher priority. 2-hop routing is done as follows. Cluster heads inside half energy distance from the base station communicate with the base station directly. Those outside half energy distance have to decide whether they choose 2-hop routing or 1-hop routing. To do this, each cluster head outside half energy distance calculates the energy consumption needed to communicate with the base station via 1-level cluster head or directly. If less energy is needed when passing through the 1-level cluster head, 2-hop routing is chosen and if not, 1-hop routing is chosen. After routing is done each sensor nodes start sensing data.

Influence of the Salience of the Formal Science Education on the Attitude toward Science Communication through the Mass Media (형식적 과학교육의 부감점에 따른 비형식적 과학교육 매체로서의 과학보도 수용 태도 연구)

  • Pak, Sung-Jae;Yoo, June-Hee
    • Journal of The Korean Association For Science Education
    • /
    • v.19 no.2
    • /
    • pp.275-292
    • /
    • 1999
  • This study aimed to explore the saliences of formal school science and their influences on the attitude toward science communication through mass media. Saliences of school science are salient memories of school science which a perciever attends to selectively among various aspects of formal school science. Among saliences. external saliences refer to the sensory aspects of formal school science. and internal saliences refer to the observers' cognition. Attitude toward science communication through mass media constitute six scales; exposure. cognition. focus. belief. self perception of understanding. application. The questionnaire were developed and sample was selected by multi-stage stratified clustering. The sample size was 1,825. The data was analysed by correlation and multiple stepwise regression. Positive saliences were lab work and science teacher and negative saliences were lecture and exam/grade. According to the correlation and multiple stepwise regression analysis. saliences of the formal school science could account only a small part of the attitude toward science communication through mass media. Internal salieces could account the attitude toward science communication than external salience. Further studies on new models including attitude towards science are needed.

  • PDF

An Efficient Video Sequence Matching Algorithm (효율적인 비디오 시퀀스 정합 알고리즘)

  • 김상현;박래홍
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.41 no.5
    • /
    • pp.45-52
    • /
    • 2004
  • According tothe development of digital media technologies various algorithms for video sequence matching have been proposed to match the video sequences efficiently. A large number of video sequence matching methods have focused on frame-wise query, whereas a relatively few algorithms have been presented for video sequence matching or video shot matching. In this paper, we propose an efficientalgorithm to index the video sequences and to retrieve the sequences for video sequence query. To improve the accuracy and performance of video sequence matching, we employ the Cauchy function as a similarity measure between histograms of consecutive frames, which yields a high performance compared with conventional measures. The key frames extracted from segmented video shots can be used not only for video shot clustering but also for video sequence matching or browsing, where the key frame is defined by the frame that is significantly different from the previous fames. Several key frame extraction algorithms have been proposed, in which similar methods used for shot boundary detection were employed with proper similarity measures. In this paper, we propose the efficient algorithm to extract key frames using the cumulative Cauchy function measure and. compare its performance with that of conventional algorithms. Video sequence matching can be performed by evaluating the similarity between data sets of key frames. To improve the matching efficiency with the set of extracted key frames we employ the Cauchy function and the modified Hausdorff distance. Experimental results with several color video sequences show that the proposed method yields the high matching performance and accuracy with a low computational load compared with conventional algorithms.

Carbon, Nitrogen and Phosphorous Ratios of Zooplankton in the Major River Ecosystems (국내 주요 강 생태계 내 동물플랑크톤의 탄소, 질소, 인 비율 해석)

  • Kim, Hyun-Woo;La, Geung-Hwan;Jeong, Kwang-Seuk;Kim, Dong-Kyun;Hwang, Soon-Jin;Lee, Jaeyong;Kim, Bomchul
    • Korean Journal of Ecology and Environment
    • /
    • v.46 no.4
    • /
    • pp.581-587
    • /
    • 2013
  • The amounts of carbon (C), nitrogen (N) and phosphorus (P) in relation to dry weight (D.W.) were measured in zooplankton from the large four rivers (Han R., Geum R., Yeongsan R. and Seomjin R.) during 2004~2008. The stoichiometry of total zooplankton in four river systems was highly variable. The ranges of average C, N and P-contents were $70{\sim}620mgC\;mg^{-1}$ D.W., $7.1{\sim}85.5{\mu}gN\;mg^{-1}$ D.W. and $2.5{\sim}7.4{\mu}gP\;mg^{-1}$ D.W., respectively. The mean C :N: P atomic ratios reflected large spatial differences. The C : P and N : P ratios of the zooplankton community ranged from 38 to 392 : 1 and from 4 to 65 : 1 in all sampling sites. Self-Organizing Map (SOM) was applied to the survey data, and the study sites were clearly classified into 3 clusters. Clustering was largely affected by the distribution pattern of C, N, P-contents, which is related with characteristics of river systems on the basis of stoichiometry.

The Spatial Distribution Characteristics and Determinants of Strong Small Farm: Focusing on Apples (강소농의 공간적 분포특성과 결정요인 분석 -사과를 중심으로-)

  • Kim, Hyun Joong;Lee, Seong Woo
    • Journal of Agricultural Extension & Community Development
    • /
    • v.19 no.4
    • /
    • pp.961-987
    • /
    • 2012
  • The present study is to investigate the characteristics and determinants of spatial distribution of strong small farm by defining the term, strong small farm (SSF) extracting the SSF households data dealing with apples, from 2010 Census of Agriculture, Forestry and Fisheries, Korea. Spatial distribution and concentration of SSF are analyzed based on spatial clustering techniques. We construct discrete dependent variables on strong and non-strong small farms and then analyze the determinants of the SSFs using probit model, with independent variables including population and economic characteristics and management characteristics. As of 2010, the apple SSFs, 1,529 households in total, are geographically concentrated in Gyeonsangbuk-do according to the analysis results. The determinants of SSF are similar to those of farms' earnings. When located in the apple producing area, and participating in producers organization while selling products directly, the farm is highly likely an SSF. The findings and results of the present study are expected to provide fundamental information helpful for preparing and implementing policies for SSFs in that the present study investigates the characteristics of SSF, which is a prerequisite step for SSF-related policies.

Morphological Characteristics and Genetic Diversity Analysis of Cultivated Sancho (Zanthoxylum schinifolium) and Chopi (Zanthoxylum piperitum) in Korea (국내 재배지의 산초(Zanthoxylum schinifolium)와 초피(Zanthoxylum piperitum)의 형태학적 특성과 유전적 다양성)

  • Ryu, Jaihyunk;Choi, Hae-Sik;Lyu, Jae-il;Bae, Chang-Hyu
    • Korean Journal of Plant Resources
    • /
    • v.29 no.5
    • /
    • pp.555-563
    • /
    • 2016
  • The morphological characteristics and genetic relationships among 32 germplasms of Zanthoxylum schinifolium and Zanthoxylum piperitum collected from two farms in Korea were investigated. The traits with the most variability were seed color, leaf size, and spine size. The intraspecific polymorphism of Z. schinifolium and Z. piperitum was 96.5% and 60.3%, respectively. The genetic diversity and Shannon’s information index values ranged from 0.11 to 0.33 and 0.19 to 0.50, with average values of 0.26 and 0.42, respectively. Two ISSR primers (UBC861 and UBC862) were able to distinguish the different species. The genetic similarity matrix (GSM) revealed variability among the accessions ranging from 0.116 to 0.816. The intraspecific GSM for Z. schinifolium and Z. piperitum was 0.177-0.780 and 0.250-0.816, respectively. The GSM findings indicate that Z. schinifolium and Z. piperitum accessions have high genetic diversity and possess germplasms qualifying as good genetic resources for cross breeding. The clustering analysis separated Z. schinifolium and Z. piperitum into independent groups, and all accessions could be classified into three categories. Z. Schinifolium var. nermis belonged to independent groups. Comparison of the clusters based on morphological analysis with those based on ISSR data resulted in an unclear pattern of division among the accessions. The study findings indicate that Z. schinifolium and Z. piperitum accessions have genetic diversity, and ISSR markers were useful for identifying Z. schinifolium and Z. piperitum.

Novel User Offloading Scheme for Small Cell Enhancement in LTE-Advanced System (LTE-Advanced 시스템에서 소형셀 향상을 위한 새로운 사용자 오프로딩 기법)

  • Moon, Sangmi;Chu, Myeonghun;Lee, Jihye;Kwon, Soonho;Kim, Hanjong;Kim, Cheolsung;Hwang, Intae
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.53 no.5
    • /
    • pp.19-24
    • /
    • 2016
  • In Long Term Evolution-Advanced (LTE-A), small cell enhancement(SCE) has been developed as a cost-effective way of supporting exponentially increasing demand of wireless data services and satisfying the user quality of service(QoS). However, due to the dense and irregular distribution of a large number of small cells, the offloading scheme should be applied in the small cell network. In this paper, we propose an user offloading scheme for SCE in LTE-Advanced system. We divide the small cells into different clusters according to the reference signal received power(RSRP) from user equipment(UE). Within a cluster, We apply the user offloading scheme with the consideration of the number of users and interference conditions. Simulation results show that proposed scheme can improve the throughput, and spectral efficiency of small cell users. Eventually, proposed scheme can improve overall cell performance.

Literature Review Nursing Intervention for Developmental Support on Preterm Infants (미숙아의 발달지지를 위한 간호중재에 관한 문헌연구)

  • Kim, Tae-Im;Sim, Mi-Kyung
    • Korean Parent-Child Health Journal
    • /
    • v.4 no.1
    • /
    • pp.35-55
    • /
    • 2001
  • Recently attention has been focused on the effects of early intervention, or its lack, on both normal and preterm infants. Particularly numerous studies suggest that premature infants are not necessarily understimulated but instead are subjected to inappropriate stimulation. Developmental support and sensory stimulation have become clinical opportunities in which nursing practice can impact on the neurobehavioral outcome of premature infants. Developmental care has been widely accepted and implemented in neonatal intensive care units across the country. Increasingly, attention and concern in caring for low-birth-weight infants and premature infants has led clinicians in the field to explore the effects of a complex of interventions designed to create and maintain a developmentally supportive environment; to provide age-appropriate sensory input; and to protect the infant from inappropriate, excessive and stressful stimulation. The components of developmental care include modifications of the macro-environment to reduce NICU light and sound levels, care clustering, nonnutritive sucking, and containment strategies, such as flexed positioning or swaddling. Sensory stimulation of the premature infants is presented to standardize the modification of a developmental intervention based on physiologic and behavioral cues. The most appropriate type of stimuli are those that are sensitive to infant cues. Evaluation of infant physiological and behavioral responds to specific intervention stimuli may help to identify more appropriate interventions based on infants' cues. A critical question confronting the clinician is that of determining when the evidence supporting a change in practice is sufficient to justify making that change. There are acknowledged limitations in the current studies. Many of the studies examined had small sample sizes; used nonprobability sampling; and used a phase lag design, which introduces the possibility of threats to internal validity and limits the generalizability of the results. Although many issues regarding the effects of developmental interventions remain unresolved, the available research base documents significant benefits of developmental care for LBW infants in consistent outcomes, without significant adverse effects. Particularly, although the individual studies vary somewhat in the definition of specific outcomes measured, instrumentation used, time and method of data collection, and preparaion of the care providers, in all studies, infants receiving the full protocol of individualized developmentally supportive care had improvements in some aspect of four areas of infant functioning: level of respiratory or oxygen support, the establishment of oral feeding; length of hospital stay, and infant behavioral regulation. In summary, based on the available literature, individualized developmental intervention should be incorporated into standard practice in neonatal intensive care. And this implementation needs to be coupled with ongoing research to evaluate the impact of an individualized developmental care programs on the short- and long-tenn health outcomes of LBW infants.

  • PDF

Development of Korean Tissue Probability Map from 3D Magnetic Resonance Images (3차원 MR 영상으로부터의 한국인 뇌조직확률지도 개발)

  • Jung Hyun, Kim;Jong-Min, Lee;Uicheul, Yoon;Hyun-Pil, Kim;Bang Bon, Koo;In Young, Kim;Dong Soo, Lee;Jun Soo, Kwon;Sun I., Kim
    • Journal of Biomedical Engineering Research
    • /
    • v.25 no.5
    • /
    • pp.323-328
    • /
    • 2004
  • The development of group-specific tissue probability maps (TPM) provides a priori knowledge for better result of cerebral tissue classification with regard to the inter-ethnic differences of inter-subject variability. We present sequential procedures of group-specific TPM and evaluate the age effects in the structural differences of TPM. We investigated 100 healthy volunteers with high resolution MRI scalming. The subjects were classified into young (60, 25.92+4.58) and old groups (40, 58.83${\pm}$8.10) according to the age. To avoid any bias from random selected single subject and improve registration robustness, average atlas as target for TPM was constructed from skull-stripped whole data using linear and nonlinear registration of AIR. Each subject was segmented into binary images of gray matter, white matter, and cerebrospinal fluid using fuzzy clustering and normalized into the space of average atlas. The probability images were the means of these binary images, and contained values in the range of zero to one. A TPM of a given tissue is a spatial probability distribution representing a certain subject population. In the spatial distribution of tissue probability according to the threshold of probability, the old group exhibited enlarged ventricles and overall GM atrophy as age-specific changes, compared to the young group. Our results are generally consistent with the few published studies on age differences in the brain morphology. The more similar the morphology of the subject is to the average of the population represented by the TPM, the better the entire classification procedure should work. Therefore, we suggest that group-specific TPM should be used as a priori information for the cerebral tissue classification.

Morphological and Genetic Characteristics of Colletotrichum gloeosporioides Isolated from Newly Emerging Static-Symptom Anthracnose in Apple

  • Jeon, Yongho;Cheon, Wonsu
    • 한국균학회소식:학술대회논문집
    • /
    • 2014.10a
    • /
    • pp.34-34
    • /
    • 2014
  • Filamentous fungi of the genus Colletotrichum (teleomorph, Glomerella) are considered major plant pathogens worldwide. Cereals, legumes, vegetables, and fruit trees may be seriously affected by this pathogen (1). Colletotrichum species cause typical disease symptoms known as anthracnoses, characterized by sunken necrotic tissue, where orange conidial masses are produced. Anthracnose appears in both developing and mature plant tissues (2). We investigated disease occurrence in apple orchards from 2013 to 2014 in northern Gyeongbuk province, Korea. Typical anthracnose with advanced symptoms was observed in all apple orchards studied. Of late, static fruit spot symptoms are being observed in apple orchards. A small lesion, which does not expand further and remains static until the harvesting season, is observed at the beginning of fruit growth period. In our study, static symptoms, together with the typical symptoms, were observed on apples. The isolated fungus was tested for pathogenicity on cv. 'Fuji apple' (fully ripe fruits, unripe fruits, and cross-section of fruits) by inoculating the fruits with a conidial suspension ($10^5$ conidia/ml). In apple inoculated with typical anthracnose fungus, the anthracnose symptoms progressed, and dark lesions with salmon-colored masses of conidia were observed on fruit, which were also soft and sunken. However, in apple inoculated with fungi causing static symptoms, the size of the spots did not increase. Interestingly, the shape and size of the conidia and the shape of the appressoria of both types of fungi were found to be similar. The conidia of the two types of fungi were straight and cylindrical, with an obtuse apex. The culture and morphological characteristics of the conidia were similar to those of C. gloeosporioides (5). The conidia of C. gloeosporioides germinate and form appressoria in response to chemical signals such as host surface wax and the fruitripening hormone ethylene (3). In this study, the spores started to germinate 4 h after incubation with an ethephon suspension. Then, the germ tubes began to swell, and subsequently, differentiation into appressoria with dark thick walls was completed by 8 h. In advanced symptoms, fungal spores of virtually all the appressoria formed primary hyphae within 16 h. However, in the static-symptom fungus spores, no primary hyphae formed by 16 h. The two types of isolates exhibited different growth rates on medium containing apple pectin, Na polypectate, or glucose as the sole carbon. Static-symptom fungi had a >10% reduction in growth (apple pectin, 14.9%; Na polypectate, 27.7%; glucose, 10.4%). The fungal isolates were also genetically characterized by sequencing. ITS regions of rDNA, chitin synthase 1 (CHS1), actin (ACT), and ${\beta}$-tubulin (${\beta}t$) were amplified from isolates using primer pairs ITS 1 and ITS 4 (4), CHS-79F and CHS-354R, ACT-512F and ACT-783R, and T1 and ${\beta}t2$ (5), respectively. The resulting sequences showed 100% identity with sequences of C. gloeosporioides at KC493156, and the sequence of the ${\beta}$t gene showed 100% identity with C. gloeosporioides at JX009557.1. Therefore, sequence data from the four loci studied proves that the isolated pathogen is C. gloeosporioides. We also performed random amplified polymorphic DNA-PCR, which showed clearly differentiated subgroups of C. gloeosporioides genotypes. The clustering of these groups was highly related to the symptom types of the individual strains.

  • PDF