• Korean Journal of Environment and Ecology
• /
• v.16 no.4
• /
• pp.441-448
• /
• 2003

To investigate the vegetation structure of mountain ridge from Nogodan to Goribong, 22 plots(500$m^2$) set up with random sampling method were surveyed Three groups Quercus mongolica-Fraxinus rhynchophylla community. Quercus mongolica- Pinus densinora community. Quercus mongolica community were classified by cluster analysis. Quercus mongolica was found as it major woody plant species in the ridge area from Nogodan to Goribong. And partly in lower elevation was occupied by deciduous broadleaved tree species and Pinus densiflora. In this area, Korean endemic species, Abies koreana was distributed small amounts. Species diversity(H') of investigated group were ranged 0.9274~1.2845 and it was similar to those of the ridgee area of the national parks in Baekdudaegan.

• Korean Journal of Materials Research
• /
• v.13 no.8
• /
• pp.550-554
• /
• 2003

Current nanogold cluster synthesized by chemical routine with 11 or 55 atoms of gold has been widely used for immuno chemistry probe as a form of nanocluster conjugated with biomolecules. It would be an undeveloped region that the 1 nm size of nanogold could be made by materials engineering processing. Therefore, objective of this study is to minimize the size of gold nanocluster as a function of operating temperature and chamber pressure in inert gas condensation (IGC) processing. Evaporation temperature was controlled by input current from 50 A to 65 A. Chamber pressure was controlled by argon gas with a range of 0.05 to 2 torr. The gold nanocluster by IGC was evaluated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The gold nanocluster for TEM analysis was directly sampled with special in-situ method during the processing. Atomic force microscopy (AFM) was used to observe 3-D nanogold layer surfaces on a slide glass for the following biomolecule conjugation step. The size of gold nanoclusters had a close relationship with the processing condition such as evaporation temperature and chamber pressure. The approximately 1 nm size of nanogold was obtained at the processing condition for 1 torr at $1124 ^{\circ}C$.

• Convergence Security Journal
• /
• v.13 no.4
• /
• pp.41-46
• /
• 2013

Routing protocol using in the existing wire network cannot be used as it is for efficient data transmission in MANET. Because it consists of only mobile nodes, network topology is changing dynamically. Therefore, each mobile node must perform router functions. Variety of routing attack like DoS in MANET is present owing to these characteristic. In this paper, we proposed cooperative-based detection method to improve detection performance of flooding attack which paralyzes network by consuming resource. Accurate attack detection is done as per calculated adaptively threshold value considered the amount of all network traffic and the number of nodes. All the mobile nodes used a table called NHT to perform collaborative detection and apply cluster structure to the center surveillance of traffic.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.28 no.4
• /
• pp.501-518
• /
• 2017

Reducing the time it takes for researchers to acquire knowledge and introduce them into research activities can be regarded as an indispensable factor in improving the productivity of research. The purpose of this research is to cluster the information usage patterns of KOSEN users and to suggest optimization method of personalized recommendation service algorithm for grouped users. Based on user research activities and usage information, after identifying appropriate services and contents, we applied a Spark based big data analysis technology to derive a personal recommendation algorithm. Individual recommendation algorithms can save time to search for user information and can help to find appropriate information.

• Journal of the Korean Home Economics Association
• /
• v.39 no.6
• /
• pp.1-14
• /
• 2001

The purpose of this research is to observe the differences in consumers behavior on clothes care based on their different lifestyles and different demographic characteristics. The research surveyed 267 women of 20 years old or older living in Taegu City. SPSS package was used for data analysis and frequency, percentage, average, standard deviation, factor analysis, cluster analysis, ANOVA(analysis of valiance). and Duncan test were used The results are as follows: 1. Lifestyle factors for the research object were found as 'Consumption-oriented','family-oriented', 'Economic-oriented','Leisure-oriented','conservatism-oriented'. The categories for analysis according to these factors are classified into 5 categories, category 1 is Leisure/Family-oriented group, category 2 Consumption/Leisure avoidance-oriented group, category 3 Economy/Family Apathy-oriented group, category 4 Conservatism-oriented group, and category 5 Consumption/Innovation group. Five factors for behavior on clothes care are found, including washing method, interest in detergent, environmental behavior, washing effectiveness, and management after washing 2. Behavior on clothes care based on lifestyle groups showed a meaningful difference according to the following: Interest in detergent(p<.05 level), environmental behavior(p<.01 level), and washing effectiveness(p< .01 level) 3. In demographic variations (such as age, monthly income, monthly expenditure on clothes), there is a meaningful difference in behavior on clothes care, such as interest in detergent or management after washing, according to different age groups. However, no meaningful difference is found in behavior on clothes care according to other demographic characteristics.

• Journal of the Korean Home Economics Association
• /
• v.34 no.3
• /
• pp.219-232
• /
• 1996

This study is intended to find changing of upper body shape according to the increase of age of elderly women, to extract the factors which form the upper body shapes and to classify the upper body shapes and grasp the characteristics of each body type. The subject were 225 elderly women aged 55-79 years old. Data were analyzed by the multivariate method, especially factor and cluster analysis. The results are as follows: 1. The items of stature, weight and width and circumference of upper body decreased according to the increase of age. And, in the length items except the side neck point - the nipple point length decreased significantly. There were significant difference of upper body shape between age groups according to each group. 2. The shape of elderly women's upper body is determined the main 6 factors(the obesity of upper body, the shape of shoulder, the length of back side of upper body, the length of front side of upper body and the size of vertical direction between stature and arm and front neck width). 3. Elderly women have 4 types of upper body shapes, which are distributed evenly. The body type of Elderly woman changes from long and fat type to small and slim, type according to the increase of age.

• Journal of the Korean Ceramic Society
• /
• v.45 no.1
• /
• pp.36-42
• /
• 2008

Carbon/$TiO_2$ composite photocatalysts were thermally synthesized with different mixing ratios of anatase to phenol resin through an ethanol solvent dissolving method. The XRD patterns revealed that only anatase phase can be identified for Carbon/$TiO_2$ composites. The diffraction peaks of carbon were not observed, however, due to the low carbon content on the $TiO_2$ surfaces and the low crystallinity of amorphous carbon. The results of chemical elemental analyses of the Carbon/$TiO_2$ composites showed that most of the spectra for these samples gave stronger peaks for carbon and Ti metal than that of any other elements. The BET surface area increases to the maximum value of $488\;m^2/g$ with the area depending on the amount of phenol resin. From the SEM images, small $TiO_2$ particles were homogeneously distributed to a composite cluster with the porosity of phenol resin-based carbon. From the photocatalytic results, the MB degradation should be attributed to the three kinds of synergetic effects, such as photocatalysis, adsorptivity, and electron transfer by light absorption between supporter $TiO_2$ and carbon.

• The Bulletin of The Korean Astronomical Society
• /
• v.36 no.1
• /
• pp.63.1-63.1
• /
• 2011

M82 is a famous starburst galaxy which is dominated by young stellar populations and ISM. Some previous studies indicated the existence of intermediate-age and old stellar population in this galaxy, but little is known about them. We present a study of old globular clusters in M82 using the Hubble Space Telescope archive data. From the cluster survey of M82 we found 650 star clusters. We divided them into disk and halo star clusters according to their position. The color-color diagrams show that all 19 halo star clusters are old globular clusters. The disk sample may include both reddened young clusters and geniune old globular clusters. We estimated their ages using spectral energy distribution fit method with six filter data covering from ultraviolet (F330W) to infrared (F160W), and found that 30 of them are older than 3 Gyr. These are considered to be disk globular clusters. Twelve of the halo globular clusters are found to be partially resolved into their member stars. The (B-V) color range of the halo globular clusters is consistent with that of the Milky Way globular clusters, but most of M82 globular clusters are bluer than (B-V)=0.7. The existence of these old globular clusters suggests that the starburst galaxy M82 has an old stellar halo that may be as old as the Milky Way halo.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.7
• /
• pp.1072-1077
• /
• 2017

Mean-reverting analysis refers to a way of estimating the underlining tendency after new data has evoked the variation in the equilibrium state. In this paper, we propose a new method to interpret the specular portraits of Premature Ventricular Contraction(PVC) arrhythmia by applying K-means unsupervised learning algorithm on electrocardiogram(ECG) data. Aiming at this purpose, we applied a mean-reverting model to analyse Heart Rate Variability(HRV) in terms of the modified poincare plot by considering PVC rhythm as the component of disrupting the homeostasis state. Based on our experimental tests on MIT-BIH ECG database, we can find the fact that the specular patterns portraited by K-means clustering on mean-reverting HRV data can be more clearly visible and the Euclidean metric can be used to identify the discrepancy between the normal sinus rhythm and PVC beats by the relative distance among cluster-centroids.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.1
• /
• pp.209-218
• /
• 2016

This study analyzed the data using the phenomenological method proposed by Colaizzi (1978) to understand the meaning and reality of the health care experience of clinical nurses in a university hospital. The data were collected from 9 participants, who were nurses in a university hospital in the city of S from Oct 4, 2015 to Oct 30, 2015. The results showed that the health care experiences of the participants may be categorized into 5 categories, 'ambivalence toward the physical health care', 'pressure over physical exercise', 'the difficulty arising out of shift work', 'stress management', and 'rediscovery of self', and may be identified with a 14 theme cluster and 42 themes.