• Korean Journal of Ecology and Environment
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• v.45 no.4
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• pp.356-367
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• 2012

Community structure of fish and inhabiting status of endangered species, Cobitis choii and Gobiobotia naktongensis were investigated in the Ji Stream, a tributary of the Geum River Drainage System of Korea from May to October 2011. Ten to 23 fish species inhabited upper stream (St. 1~St. 4) with a Aa-Bb river type composed of mostly pebble and cobble bottoms, 16~28 species did middle stream (St. 5~St. 7) with a Bb type composed of mostly cobble and boulder bottoms, and 20-29 species did lower stream (St. 8~St. 10) with a Bb-Bc type composed of mostly sand bottoms. A total of 44 species belonging to nine families were found in the stream during the survay. The dominant species were in the order of Zacco platypus (37.2%), Pungtungia herzi (5.8%) and Pseudogobio esocinus (5.5%). Other abundant species included Acheilognathus lanceolatus (5.3%), Zacco koreanus (5.2%), Hemibarbus longirostris (4.9%) and Squalidus gracilis majimae (3.5%). Among residing species, 16 species were endemic to Korea, two (Cobits choii and Gobiobotia naktongensis) were endangered, and one (Micropterus salmoides) was non-indigenous. The similarity index based on species composition and abundance clearly delineated the fish community of the Ji Stream according to the three major sections, which were defined at the above. Dominance index gradually decreased toward downstream, while diversity, evenness and species richness indexes gradually increased toward downstream. The two endangered species, C. choii and G. naktongensis co-occurred at the lower stream due to the prevalence of a sandy substratum.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.151-162
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• 2009

When viewing that since the 1990s local governments have tried to build golf courses as a plan to revitalize the attraction of home and abroad tourists and to increase their tax incomes and that big companies are interested in leisure business including golf courses as a future promising business in the 21st century, golf courses seem to continuously increase in the future. On the contrary, noticing that golf courses are not only the main culprit behind the damage of natural environment and environmental pollution but also a target of real estate speculation and that golf makes a sense of incongruity between the classes of a society as a luxury sports, environment activists and local residents raise criticism to golf. Golf in our country shows a special sports phenomenon of which the pros and cons appear continuously. So, it is judged that policy for golf development direction should be set up based on verified scientific data. Thus, the research aims at deriving the location types of golf courses by looking at laws from the period of formation of the initial domestic golf courses to the recent period, grasping their distribution status according to time series and regions, conducting a questionnaire survey regarding location factors for golfers and the workers of golf courses, and dividing golf courses into several types. It is expected that the research will be a fundamental material when a golf course is built later on, contributing to the research of golf courses.

• The korean journal of orthodontics
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• v.32 no.2 s.91
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• pp.91-105
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• 2002

In general, orthodontists make problem lists and treatment plans based on norms of several cephalometric standards. But consideration of dentoalveolar compensation, which tends to maintain normal dental arch relationship in various skeletal jaw relationships, helps orthodontists make more individualized treatment objectives and plans. The purpose of this study was to classify skeletal patterns of normal occlusion samples by cluster analysis and to investigate the dentoalveolar compensation according to skeletal patterns. The subjects were consisted of 125 subjects who were normal occlusion samples at Seoul National University Dental Hospital, Department of Orthodontics. Lateral cephalograms in centric occlusion were traced and digitized. The skeletal patterns of normal occlusion samples were classified into three horizontal groups and three vertical groups by cluster analysis and ANOVA on the skeletal and dentoalveolar measurements among the groups were carried out. The results were as follows ; 1. Anteroposterior and vertical skeletal relationships of normal occlusion samples were very variable. 2. As the mandibular position was anterior to the maxilla, the maxillary incisors inclined more labially, the mandibular incisors more lingually, and the occlusal plane was flattened due to the anteroposterior dentoalveolar compensation. dentoalveolar height was decreased and upper posterior teeth was uprighted to the palatal plane and lower incisors and lower posterior teeth to the mandibular plane. 4. Lower incisors were more strongly associated with the dentoalveolar compensation than upper incisors according to the anteroposterior and vertical skeletal relationship.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.371-378
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• 2014

The subject of this study is the Gongchon-cheon which is one of the largest streams in Incheon and is closely related to lives of citizen. Comparative analysis is made on the changes of the environment and the ecological condition of Gongchon-cheon after the stream naturalization construction which is completed in July 2009. From the results of the survey, 32 species in 2004, 22 species in 2009 and 46 species in 2010 have been recorded. The number of the species decreased from 2004 to 2009 due to the disturbance of the river environment, and it increased in a short time from 2009 to 2010 because of the recovery of the environment. It demonstrates the stream naturalization construction providing enough environments (dikes and rapids) for the benthic macro invertebrates. The result of the present study is similar with the river's biology index, ESB index, and KSI index, and also it is similar with the pattern of the appearance, which illustrates that the species decreased during the naturalization construction, and increased after the stabilization since the finish of the naturalization construction, and it has been confirmed that the naturalization construction provides the better environment for the inhabitation of organisms.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.421-426
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• 2017

These experiments were conducted to investigate the morphological characteristics, occurrence ecology, host preference, and oviposition of Locusta migratoria to create a forecasting manual in preparation for outbreaks of this species. The sex ratio (female:male) of 274 adult of L. migratoria which occurred naturally in the Muan region of Jeollanam-do was 18.2 : 81.8, 60.9% individuals were of the green type and 39.1% were of the brown type. Body length and body weight were 6.5 cm and 2.8 g for females and 5.0 cm and 1.5 g for males, respectively; body size did not differ between differently colored individuals. Spawning activity in the field was observed from late August to late October. Eggs laid between late September and early October hatched in late May the following year. Female adults fed 3.5 g of corn leaf and male adult was 1.6 g for a day. The host preference of L. migratoria was in the order corn > foxtail millet > millet > silver grass > rice, and preference for silver grass and rice was very low. Pure sand was most favorable for the spawning of L. migratoria, and the cumulative amount of hatching was higher when the soil moisture content was higher after spawning began.

• Knowledge Management Research
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• v.23 no.3
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• pp.259-284
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• 2022

In order to help the understanding of web novel users, this study was intended to quantitatively verify the user's behavioral types according to the characteristics of web novels. For this purpose, the direction of the study proceeded as follows. First, the motives of web novel users were investigated by referring to the motives of other digital content users. In addition, specific behavioral types of users were also collected. As a result, the motivation for using web novels was found to be 'interpersonal relationships and information acquisition with others', 'leisure activities', and 'escape from reality/relieve tension'. After that, the groups were classified as to whether there was a difference between groups according to the motives of use. As a result, the 'hobbies' type, a group with a particularly high motivation for using leisure activities, the 'stress relief' type, a group with very high escapism and tension relief characteristics, and a group with high interpersonal relationships and information acquisition with others The 'communication' type was classified as a 'multipurpose' type with high overall motivation characteristics. Then, in order to find out the specific characteristics between the types, personas were constructed based on the different behavior type data. Through this, the theoretical contribution of this study is meaningful in that it revealed the motives of web novel users. As a practical contribution, the persona was formed by combining the users' motives and behavioral patterns and visualized to be close to the actual representative users. These results are expected to help improve the web novel service by providing useful indicators for actual writers, platform managers, and users.

• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.4
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• pp.1-7
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• 2001

Remotely sensed data is the most fundamental data in acquiring the GIS informations, and may be analyzed to extract useful thematic information. Multi-spectral classification is one of the most often used methods of information extraction. The actual multi-spectral classification may be performed using either supervised or unsupervised approaches. This paper analyze the effect of assigning clever initial values to image classes on the performance of parallelepiped classification algorithm, which is one of the supervised classification algorithms. First, we investigate the effect on serial computing model, then expand it on MIMD(Multiple Instruction Multiple Data) parallel computing model. On serial computing model, the performance of the parallel pipe algorithm improved 2.4 times at most and, on MIMD parallel computing model the performance improved about 2.5 times as clever initial values are assigned to image class. Through computer simulation we find that initial values of image class greatly affect the performance of parallelepiped classification algorithms, and it can be improved greatly when classes on both serial computing model and MIMD parallel computation model.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.347-355
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• 2008

This research has been conducted against Cheong-Ju undergraduate students. A total of 213 questionnaires was used for the data. The first purpose of this research is to analyze eating habits of food-related lifestyle of the students. The second purpose is to classify them into groups depending on their food-related lifestyle. The third purpose of this research is to identify eating out behavior patters among the groups classified by food-related lifestyle. Based on the information obtained from those results, this study would help restaurants have their marketing strategies. From the factor analysis, 6 factors of "popular-oriented group", "health-oriented group", "safety-oriented group", "decoration-oriented group", "tasted-oriented group" and "wellbeing-oriented group" were extracted. Additionally, "safety type group", "passive food groups" and "high-interest in foods group" were classified from the cluster analysis.

• 한국노년학
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• v.32 no.3
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• pp.895-912
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• 2012

The authors aimed to identify the patterns of mutual support between aged parents and their adult offsprings and to analyze the demographic and social characteristics of each pattern and the quality of living for the aged parents. The data of the study were drawn from the 2008 Survey of the Living Conditions and Welfare for the Elderly published by the Ministry of the Health and Welfare. The sample of our analysis was 14,843 aged persons with their adult offsprings. A cluster analysis produced four types of mutual support patterns: High mutual supporters, parents as beneficiaries, parents as benefactors, ans low mutual supporters, with parents as benefactors as the most frequent pattern of mutual support. The study showed that the group of high mutual supporters was highest in the quality of life while the group of parents as beneficiaries lowest. This findings imply that the support relationship between old people and their adult offsprings may undergo transformation towards a two-way relation of mutual support.

• Information and Communications Magazine
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• v.33 no.5
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• pp.3-11
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• 2016

자연계에서 존재하는 다양한 생명체는 자신들의 생존과 종의 번성을 위해 효율적인 행동 규칙을 만들어 진화해 왔다. 이러한 생명체의 다양한 생존원리로부터 착안을 하여 자연계가 아닌 다른 환경에서 적용이 가능하도록 알고리즘을 만들어 적용시키는 것을 생체모방 알고리즘이라 한다. 자연계의 환경자체가 불확실한 변화가 다양하게 포함되고 있으며, 제한된 자원 환경을 어떻게 효율적으로 활용하는가의 문제가 걸려 있음으로 인하여 이러한 생체모방 알고리즘은 적용환경의 변환에 빠른 적응력을 제공할 수 있고, 자원 제약형 환경에서 안정적으로 확장성과 적응성을 제공할 수 있어서 상호 운용성 측면에서 많은 이득을 줄 수 있다. 이와 같은 생체모방 알고리즘을 네트워크의 관점에서 적용시켜 보면, 전자의 경우에는 자율적인 네트워크 구성을 용이하게 제공할 수 있음을 나타내고, 후자의 경우에는 IoT 환경과 같은 자원 제약형 환경에서의 상호 운용성을 제공할 수 있다. 이렇듯이 생체모방 알고리즘을 네트워크에 접목시켜 연구하는 것은 최근의 네트워크 분야의 연구 이슈와 상호 보완적으로 작용하여 시너지 효과를 제공할 수 있다. 자연계의 군집 현상 및 동기화 현상을 네트워크 환경에서 적용하여 사용할 수 있는 생체모방 알고리즘 기술은 다양하게 존재하고 있으며 이를 활용하는 연구를 통해 SDN(Software Defined Networking)에서의 자율제어 네트워크 구성에 접목하거나 IoT 환경과 같은 자원 제약형 환경에서의 보다 효율적인 상호 연결성을 제공하는 방향으로 발전할 수 있다. 이러한 생체모방 자율제어 네트워크 환경 구현을 위해 기존의 OpenFlow 환경과 새로이 부각되는 P4: Programming Protocol-Independent Packet Processors 기술에 대해서 정리하여 향후 생체모방 자율제어 네트워크 구현 방안을 제시하고자 한다.