• Title/Summary/Keyword: cluster value

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Marine Environments and Ecological Characteristics of Phytoplankton in Southern Coastal Waters During June to October in 2004-2006 (2004-2006년 6-10월 동안의 남해중부연안 해역특성 및 식물플랑크톤의 군집생태)

  • Cho, Eun-Seob;Lee, Sang-Yong;Kim, Sang-Soo;Choi, Yoon-Seok
    • Journal of Environmental Science International
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    • v.16 no.8
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    • pp.941-957
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    • 2007
  • This study monitored marine environments and ecological characteristics of phytoplankton in southern coastal waters during June to October in 2004-2006 and provided an information to how Cochlodinium blooms have occurred. A total of sampling sites was 16 (Dukyang bay, Goheung, Yeoja bay, Gamak bay, Gwangyang bay, Yeosu, and Namhae). Temperature ranged from $19^{\circ}C\;to\;29^{\circ}C$, which all of sampling in Yeoja bay was the highest temperature of $27^{\circ}C\;and\;29^{\circ}C$ during summer. On June, July, September, and October did not show a remarkable difference regardless of sampling sites. Yeoja and Gwangyang bays had 25-27 in salinity that was lower approximately 5-6 compared with other sampling sites. Chlorophyll had considerable fluctuations depending on sampling sites on July and October, in particular, Gwangyang bay was the highest value of $15{\mu}gl^{-1}$ that had five times as much as. Unlikely to temperature, salinity, and chlorophyll, transparency ranged from 2 m to 5 m regardless of sampling sites. Gwangyang bay was the highest DIN (Dissolved Inorganic Nitrogen) of $0.53mgl^{-1}$ on July and August that had ten times as much as, whereas DIP (Dissolved Inorganic Phosphorus) did not show a significant difference between sampling sites. On July, the correlation of DIN and chlorophyll was a negative that should extremely require DIN to grow phytoplankton, but was a positive liner on August. Mean cell number of phytoplankton reached to encounter a peak of 500 cells $ml^{-1}$ in July and August, which diatoms were dominant species and attained an abundance of >60% regardless of months. In August, the occurrence of dinoflagellates ranged from 20% to 30%. Skeletonema costatum, one of dominant speicies, was the highest occurrence to throughout sampling sites during 2004 to 2006. On the basis of cluster analysis for phytoplankton, they were distributed in all of sampling sites. Consequently, significant fluctuations of marine environments were shown in summer and S. costatum was regarded as the representive phytoplankton in southern coastal waters. In particular, the outbreaks of Cochlodinium polykrikoides have occurred in Dukyang bay, Gamak bay, Goheung, Yeosu, and Namhae, but Yeoja and Gwangyang bays did not occur. The distinguish characteristics of occurring sampling sites and non-occurring in Cochlodinium blooms based on this study was DIN that was enough to persistently grow and maintain them even a litter dissolved in water. This suggests that Cochlodinium red tide seems to be occur in off waters.

A Graph Layout Algorithm for Scale-free Network (척도 없는 네트워크를 위한 그래프 레이아웃 알고리즘)

  • Cho, Yong-Man;Kang, Tae-Won
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.5_6
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    • pp.202-213
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    • 2007
  • A network is an important model widely used in natural and social science as well as engineering. To analyze these networks easily it is necessary that we should layout the features of networks visually. These Graph-Layout researches have been performed recently according to the development of the computer technology. Among them, the Scale-free Network that stands out in these days is widely used in analyzing and understanding the complicated situations in various fields. The Scale-free Network is featured in two points. The first, the number of link(Degree) shows the Power-function distribution. The second, the network has the hub that has multiple links. Consequently, it is important for us to represent the hub visually in Scale-free Network but the existing Graph-layout algorithms only represent clusters for the present. Therefor in this thesis we suggest Graph-layout algorithm that effectively presents the Scale-free network. The Hubity(hub+ity) repulsive force between hubs in suggested algorithm in this thesis is in inverse proportion to the distance, and if the degree of hubs increases in a times the Hubity repulsive force between hubs is ${\alpha}^{\gamma}$ times (${\gamma}$??is a connection line index). Also, if the algorithm has the counter that controls the force in proportion to the total node number and the total link number, The Hubity repulsive force is independent of the scale of a network. The proposed algorithm is compared with Graph-layout algorithm through an experiment. The experimental process is as follows: First of all, make out the hub that exists in the network or not. Check out the connection line index to recognize the existence of hub, and then if the value of connection line index is between 2 and 3, then conclude the Scale-free network that has a hub. And then use the suggested algorithm. In result, We validated that the proposed Graph-layout algorithm showed the Scale-free network more effectively than the existing cluster-centered algorithms[Noack, etc.].

Effect of substrate bias voltage on a-C:H film (기판 bias 전압이 a-C:H 박막의 특성에 미치는 영향)

  • 유영조;김효근;장홍규;오재석;김근식
    • Journal of the Korean Vacuum Society
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    • v.6 no.4
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    • pp.348-353
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    • 1997
  • Hydrogenated amorphous carbon(a-C:H) films were deposited on p-type Si(100) by DC saddle-field plasma enhanced CVD to investigate the effect of substrate bias on optical properties and structural changes. They were deposited using pure methane gas at a wide range of substrate bias at room temperature and 90 mtorr. The substrate bias voltage ($V_s$) was employed from $V_s=0 V$ to $V_s=400 V$. The information of optical properties was investigated by photoluminescence and transmitance. Chemical bondings of a-C:H have been explored from FT-IR and Raman spectroscopy. The thickness and relative hydrogen content of the films were measured by Rutherford backscattering spectroscopy (RBS) and elastic recoil detection (ERD) technigue. The growth rate of a-C:H film was decreased with the increase of $V_s$, but the hydrogen content of the film was increased with the increase of $V_s$. The a-C:H films deposited at the lowest $V_s$ contain the smallest amount of hydrogen with most of C-H bonds in the of $CH_2$ configuration, whereas the films produced at higher $V_s$ reveal dominant the $CH_3$ bonding structure. The emission of white photoluminescence from the films were observed even with naked eyes at room temperature and the PL intensity of the film has the maximum value at $V_s$=200 V. With $V_s$ lower than 200 V, the PL intensity of the film increased with V, but for V, higher than 200 V, the PL intensity decreased with the increase of $V_s$. The peak energy of the PL spectra slightly shifted to the higher energy with the increase of $V_s$. The optical bandgap of the film, determined by optical transmittance, was increased from 1.5 eV at $V_s$=0V to 2.3 eV at $V_s$=400 V. But there were no obvious relations between the PL peak and the optical gap which were measured by Tauc process.

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Genetic Diversity and Relationship by SSR Markers of Korean Soybean Cultivars (한국 콩 육성품종의 SSR마커에 의한 유전적 다양성과 유연관계)

  • Kim Seong-Hun;Jung Jong-Wook;Moon Jung-Kyung;Woo Sun-Hee;Cho Yong-Gu;Jong Seung-Keun;Kim Hong-Sig
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.3
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    • pp.248-258
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    • 2006
  • Genetic diversity of 91 Korean soybean cultivars was assessed with 20 simple sequence repeat (SSR). Twenty SSR loci generated a total of 149 alleles. The number of alleles for each SSR locus ranged from 3 to 15 with a mean of 7.5 alleles. Genetic diversity estimated by PIC value of 91 cultivars was ranged from 0.424 to 0.905 with an average of 0.711. Cluster analysis based on Nei's genetic distances classified 91 soybean cultivars except Geomjeongkong 4 into 7 groups. The majority groups were I, IV, and VI which included 26, 24, and 18 cultivars, respectively. Obvious differences in genetic diversity appeared to be related with the released periods of cultivars and utilization type of cultivars, but not with breeding sites. Cultivars released in 1970's and in 1990's showed the lowest and the highest genetic diversities with 0.576 and 0.706, respectively. Soybean cultivars for vegetable and early maturity showed the lowest genetic diversity with 0.514, while those for soy sauce and tofu showed the highest genetic diversity with 0.691. Genetic distance between soybean cultivar groups developed before 1969 and during 1970's was the nearest, while genetic distance between those developed in 1970's and 1990's was the furthest. Cultivar group for vegetable and early maturity showed the furthest genetic distance with cultivar group for soy sauce and tofu, while it showed the nearest genetic distance with cultivar group for cooking with rice. Genetic distance was greater between soybean cultivar groups developed in Suwon and Iksan than between those developed in Milyang and Iksan.

Big Five Personality in Discriminating the Groups by the Level of Social Sims (심리학적 도구 '5요인 성격 특성'에 의한 소셜 게임 연구: <심즈 소셜> 게임의 분석사례를 중심으로)

  • Lee, Dong-Yeop
    • Cartoon and Animation Studies
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    • s.29
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    • pp.129-149
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    • 2012
  • The purpose of this study was to investigate the clustering and Big Five Personality domains in discriminating groups by level of school-related adjustment, as experienced by Social Sims game users. Social Games are based on web that has simple rules to play in fictional time and space background. This paper is to analyze the relationships between social networks and user behaviors through the social games . In general, characteristics of social games are simple, fun and easy to play, popular to the public, and based on personal connections in reality. These features of social games make themselves different from video games with one player or MMORPG with many unspecific players. Especially Social Game show a noticeable characteristic related to social learning. The object of this research is to provide a possibility that game that its social perspective can be strengthened in social game environment and analyze whether it actually influences on problem solving of real life problems, therefore suggesting its direction of alternative play means and positive simulation game. Data was collected by administering 4 questionnaires (the short version of BFI, Satisfaction with life, Career Decision-.Making Self-.Efficacy, Depression) to the participants who were 20 people in Seoul and Daejeon. For the purposes of the data analysis, both Stepwise Discriminant analysis and Cluster analysis was employed. Neuroticism, Openness, Conscientiousness within the Big Five Personality domains were seen to be significant variables when it came to discriminating the groups. These findings indicated that the short version of the BFI may be useful in understanding for game user behaviors When it comes to cultural research, digital game takes up a significant role. We can see that from the fact that game, which has only been considered as a leisure activity or commercial means, is being actively research for its methodological, social role and function. Among digital game's several meanings, one of the most noticeable ones is the research on its critical, social participating function. According to Jame Paul gee, the most important merit of game is 'projected identity'. This means that experiences from various perspectives is possible.[1] In his recent autobiography , he described gamer as an active problem solver. In addition, Gonzalo Francesca also suggested an alternative game developing method through 'game that conveys critical messages by strengthening critical reasons'. [2] They all provided evidences showing game can be a strong academic tool. Not only does a genre called social game exist in the field of media and Social Network Game, but there are also some efforts to positively evaluate its value Through these kinds of researches, we can study how game can give positive influence along with the change in its general perception, which would eventually lead to spreading healthy game culture and enabling fresh life experience. This would better bring out the educative side of the game and become a social communicative tool. The object of this game is to provide a possibility that the social aspect can be strengthened within the game environment and analyze whether it actually influences the problem solving of real life problems. Therefore suggesting it's direction of alternative play means positive game simulation.

EFFICIENCY OF ENERGY TRANSFER BY A POPULATION OF THE FARMED PACIFIC OYSTER, CRASSOSTREA GIGAS IN GEOJE-HANSAN BAY (거제${\cdot}$한산만 양식굴 Crassostrea gigas의 에너지 전환 효율)

  • KIM Yong Sool
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.13 no.4
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    • pp.179-183
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    • 1980
  • The efficiency of energy transfer by a population of the farmed pacific oyster, Crassostrea gigas was studied during culture period of 10 months July 1979-April 1980, in Geoje-Hansan Bay near Chungmu City. Energy use by the farmed oyster population was calculated from estimates of half-a-month unit age specific natural mortality rate and data on growth, gonad output, shell organic matter production and respiration. Total mortality during the culture period was estimated approximate $36\%$ from data on survivor individual number per cluster. Growth may be dual consisted of a curved line during the first half culture period (July-November) and a linear line in the later half period (December-April). The first half growth was approximated by the von Bertalanffy growth model; shell height, $SH=6.33\;(1-e^{0.2421(t+0.54)})$, where t is age in half-a-month unit. In the later half growth period shell height was related to t by SH=4.44+0.14t. Dry meat weight (DW) was related to shell height by log $DW=-2.2907+2.589{\cdot}log\;SH,\;(2, and/or log $DW=-5.8153+7.208{\cdot}log\;SH,\;(5. Size specific gonad output (G) as calculated by condition index of before and after the spawning season, was related to shell height by $G=0.0145+(3.95\times10^{-3}{\times}SH^{2.9861})$. Shell organic matter production (SO) was related to shell height by log $SO=-3.1884+2.527{\cdot}1og\;SH$. Size and temperature specific respiration rate (R) as determined in biotron system with controlled temperature, was related to dry meat weight and temperature (T) by log $R=(0.386T-0.5381)+(0.6409-0.0083T){\cdot}log\;DW$. The energy used in metabolism was calculated from size, temperature specific respiration and data on body composition. The calorie contents of oyster meat were estimated by bomb calorimetry based on nitrogen correction. The assimilation efficiency of the oyster estimated directly by a insoluble crude silicate method gave $55.5\%$. From the information presently available by other workers, the assimilation efficiency ranges between $40\%\;and\;70\%$. Twenty seven point four percent of the filtered food material expressed by energy value for oyster population was estimated to have been rejected as pseudofaeces : $17.2\%$ was passed as faeces; $35.04\%$ was respired and lost as heat; $0.38\%$ was bounded up in shell organics; $2.74\%$ was released as gonad output, $2.06\%$ was fell as meat reducing by mortality. The remaining $15.28\%$ was used as meat production. The net efficiency of energy transfer from assimilation to meat production (yield/assimilation) of a farm population of the oyster was estimated to be $28\%$ during culture period July 1979-April 1980. The gross efficiency of energy transfer from ingestion to meat production (yield/food filtered) is probably between $11\%\;and\;20\%$.

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The Relationship Between Social Security Network and Security Life Satisfaction in Community Residents: Scale Development and Application of Social Security Network (사회안전망과 지역사회주민의 안전생활만족의 관계: 사회안전망 척도개발과 적용)

  • Kim, Chan-Sun
    • The Journal of the Korea Contents Association
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    • v.14 no.6
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    • pp.108-118
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    • 2014
  • The purpose of this study is to develop a relationship of measuring method for the social security network and verify its validity and reliability and apply it to investigate the due to security life satisfaction. This study is based by setting general residents of Seoul in 2013 and using the stratified cluster random sampling method to analyze a total amount of 203 examples. The measuring methods for the social security network was developed through document research, conceptual definition and drafting the survey, experts' conference, preliminary inspection and original examination, verification of the validity and reliability of the survey. An experts' conference took pace to verify the validity of the survey, and 6 factors were extracted through exploratory factor analysis crime prevention design, street CCTV facilities, volunteer neighborhood patrol, local government security education, police public peace service, private security service. The conclusion are the following. Collected data was analyzed based on the aim of this study using SPSSWIN 18.0, and practice frequency analysis, F test, factor analysis, reliability analysis, correlation analysis, multiple regression analysis. First, the validity of the social security network measurement is very high. Thus, the factors constituting the social security network were found to be crime prevention design, street CCTV facilities, volunteer neighborhood patrol, local government security education, police public peace services, and private security services, and the crime prevention design factor was found to be most explanatory. Second, the reliability of the social security network measurement is very high. Thus, the correlation between the questions and the sector, the questions and the social security net was very high, and the internal consistency showed a Cronbach's${\alpha}$ value of over 0.865. Third, the establishment of a social security network had the biggest effect on people in their forties. Thus, when the crime prevention design, street CCTV facilities, local government security education, police public peace services are systematically established, the social anxiety of citizens was reduced.

Seasonal and Spatial Distribution of Soft-bottom Polychaetesin Jinju Bay of the Southern Coast of Korea (진주만에서 저서 다모류의 시 · 공간 분포)

  • Kang Chang Keun;Baik Myung Sun;Kim Jeong Bae;Lee Pil Yong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.1
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    • pp.35-45
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    • 2002
  • Seasonal quantitative van Veen grab sampling was conducted to characterize the composition and structure of the benthic polychaete community inhabiting the shellfish farming ground of a coastal bay system of Jiniu Bay (Korea). A total of 132 polychaete species were identified and the polychaetes accounted for about $80\%$ of overall abundance of benthic animals. There was little significant seasonal difference in densities (abundances) of polychaetes, Maximum biomass was obseued in summer (August) and minimum value was recorded in winter (February) and spring (May). Conversely, diversity and richness were lowest in summer, indicating a seasonal variability in the polychaetous community structure, The cluster analysis indicated that such a seasonal variability resulted mainly from the appearance of a few small, r-selected opportunists in spring and the tubiculous species of the family Maldanidae in summer. On the other hand, several indicator species for the organically enriched environments such as Capitelia capitata, Notoniashs Jatericeus and hmbrineris sp. showed high densities during all the study period. Density and biomass of univariate measures of community structure were significantly lower in the arkshell-farming ground of the southern area than in the non-farming sites of the bay, A similar general tendency was also found in the spatial distributions of species diversity and richness. Principal component analysis revealed the existence of different groups of benthic assemblages between the arkshell-farming ground and non-farming sites, The lack of colonization of r-selected opportunists and/or tubiculous species in the former ground seemed to contribute to the spatial differences in the composition and structure of the polychaetous communities. Although finer granulometric composition and high sulfide concentration in sediments of the arkshell-farming ground and low salinity in the northern area were likely to account for parts of the differences, other environmental variables observed were unlikely. The spatial distribution of polychaetes in Jiniu Bay may be rather closely related to the sedimentary disturbance by selection of shells for harvesting in spring.

Keyword Network Analysis for Technology Forecasting (기술예측을 위한 특허 키워드 네트워크 분석)

  • Choi, Jin-Ho;Kim, Hee-Su;Im, Nam-Gyu
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.227-240
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    • 2011
  • New concepts and ideas often result from extensive recombination of existing concepts or ideas. Both researchers and developers build on existing concepts and ideas in published papers or registered patents to develop new theories and technologies that in turn serve as a basis for further development. As the importance of patent increases, so does that of patent analysis. Patent analysis is largely divided into network-based and keyword-based analyses. The former lacks its ability to analyze information technology in details while the letter is unable to identify the relationship between such technologies. In order to overcome the limitations of network-based and keyword-based analyses, this study, which blends those two methods, suggests the keyword network based analysis methodology. In this study, we collected significant technology information in each patent that is related to Light Emitting Diode (LED) through text mining, built a keyword network, and then executed a community network analysis on the collected data. The results of analysis are as the following. First, the patent keyword network indicated very low density and exceptionally high clustering coefficient. Technically, density is obtained by dividing the number of ties in a network by the number of all possible ties. The value ranges between 0 and 1, with higher values indicating denser networks and lower values indicating sparser networks. In real-world networks, the density varies depending on the size of a network; increasing the size of a network generally leads to a decrease in the density. The clustering coefficient is a network-level measure that illustrates the tendency of nodes to cluster in densely interconnected modules. This measure is to show the small-world property in which a network can be highly clustered even though it has a small average distance between nodes in spite of the large number of nodes. Therefore, high density in patent keyword network means that nodes in the patent keyword network are connected sporadically, and high clustering coefficient shows that nodes in the network are closely connected one another. Second, the cumulative degree distribution of the patent keyword network, as any other knowledge network like citation network or collaboration network, followed a clear power-law distribution. A well-known mechanism of this pattern is the preferential attachment mechanism, whereby a node with more links is likely to attain further new links in the evolution of the corresponding network. Unlike general normal distributions, the power-law distribution does not have a representative scale. This means that one cannot pick a representative or an average because there is always a considerable probability of finding much larger values. Networks with power-law distributions are therefore often referred to as scale-free networks. The presence of heavy-tailed scale-free distribution represents the fundamental signature of an emergent collective behavior of the actors who contribute to forming the network. In our context, the more frequently a patent keyword is used, the more often it is selected by researchers and is associated with other keywords or concepts to constitute and convey new patents or technologies. The evidence of power-law distribution implies that the preferential attachment mechanism suggests the origin of heavy-tailed distributions in a wide range of growing patent keyword network. Third, we found that among keywords that flew into a particular field, the vast majority of keywords with new links join existing keywords in the associated community in forming the concept of a new patent. This finding resulted in the same outcomes for both the short-term period (4-year) and long-term period (10-year) analyses. Furthermore, using the keyword combination information that was derived from the methodology suggested by our study enables one to forecast which concepts combine to form a new patent dimension and refer to those concepts when developing a new patent.

Distribution of Benthic Macrofauna in subtidal area and on sand flat of Sindu-ri coast, Korea (신두리 해안의 조하대와 모래 갯벌에 서식하는 대형저서동물의 분포)

  • Koo, Bon Joo;Shin, Sang Ho;Woo, Han Jun
    • Journal of Wetlands Research
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    • v.7 no.2
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    • pp.69-88
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    • 2005
  • Distribution of benthic macrofauna was surveyed in the subtidal area and on the sand flat of Sindu-ri coast during July 2002. A total of 134 species, 3,511 individuals and 388g biomass of macrobenthos were sampled inclusively from the study sites. 109 species with a mean density of $1,298ind./m^2$ and biomass of $69.4g/m^2$ were collected from 10 stations established in the subtidal area. Polychaetes were represented as a dominant faunal group of the subtidal area in both species richness and density with values of 54 species and $813ind./m^2$. Cluster analysis based on the faunal composition showed that the subtidal area could be divided into four stational groups according to sedimentary characteristics: Cirrophorus armatus - Lumbrineris longifolia association on the mud sediment with pebbles near aqua-farms; Aonides oxycephala association on the rocky bed; Scoloplos armiger - Grandifoxus cuspis association on the sand-dominated sediment along the lowest low water; a association with higher evenness on the sand-dominated sediment in the depth. Although having characteristics of high value in species richness, density and species diversity, the macrobenthic association around the farming area was dominated by the opportunistic species such as Lumbrineris longifolia and Tharyx sp. Natural community represented by S. armiger and G. cuspis was developed in most sand-dominated areas. 50 species were sampled with a mean density of $2,443ind./m^2$ and biomass of $381.3g/m^2$ from eight+ stations along two transects on Sindu-ri sand flat. Mollusks were represented as a dominant faunal group of the sand flat in species richness, density and biomass with values of 20 species, $1,345ind./m^2$ and $350.4g/m^2$, respectively. Umbonium thomasi, Veneridae sp., Mandibulophoxus mai, Armandia lanceolata, Eohaustorius spinigerus, Urothoe convexa were dominant species and these species accounted for over 83% of total individuals. There were three distinct zones of macrobenthos on Sindu-ri sand flat according to the extent of exposure time. The upper zone was dominated by Scopimera globosa, the middle zone was characterized by M. mai, and the lower zone was dominated by E. spinigerus. Sindu-ri coastal area was considered as a healthy habitat for macrobenthos, except for around the farming area. It was considered that Sindu-ri coastal area including the sand flat connected to the sand dune of natural monument was a valuable habitat as a protected site in having no pollution source and no artificial structure.

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