• Korean Journal of Ecology and Environment
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• v.53 no.3
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• pp.229-240
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• 2020

In this study, the results of fish assemblage survey for 16 reservoirs in the Yeongsan·Seomjin-River watershed were presented with fish assemblage characteristics analysis in relation to reservoir size. The survey method including number of sampling sites was followed the "Biomonitoring survey and assessment manual" of the Ministry of Environment/National Institute of Environmental Research (MOE/NIER), and the reservoirs were categorized as three size groups, small, medium or large reservoirs, based on the MOE/NIER as well. Total 13 family classified into 44 species were collected from 2018 (7 reservoirs) to 2019 (9 reservoirs), and the dominant and subdominant species were Hemiculter eigenmanni (Relative abundance, RA, 32.9%) and Lepomis macrochirus (RA, 31.4%), respectively. As a result of the analysis in relation to the reservoir size, the average (±standard deviation) number of species of the small, medium and large reservoirs were 11±2.9, 14.3±2.1, 22.7±0.6, respectively, which showed positive correlation with the reservoir size. Total 6 fish assemblage characteristics(number of species, number of individuals, richness index, herbivorous fish ratio, carnivorous fish ratio, exotic fish ratio) showed significant differences between the each reservoir size groups (P<0.05). As a result of cluster analysis, 16 reservoirs were clustered into 5 groups with 60% similarity, and the each reservoirs seems to be clustered depends on the distance from each other, watershed and their historical geology rather than size. These results are baseline information for the understanding of fish assemblage in Korean reservoirs, important for establishing management policy of reservoirs in the Yeongsan·Seomjin-River watershed.

• Journal of Science Education
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• v.42 no.1
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• pp.49-65
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• 2018

Astronomy is the subject that can easily draw students' interest in studying science, therefore plays an important role in developing scientific core competence. However, it is difficult to develop spatial thinking that is required in understanding astronomical concepts through the classroom lessons. Planetarium, along with the science museum, is one of the most representative informal educational institution where astronomical concepts can be taught beyond time and space constraints. In this study, we developed the astronomy education program that is operated in the planetarium and applied the program to the elementary, middle and high-school students to investigate the effects of the planetarium lesson compared to the classroom lesson. The duration of this research was about 8 months, and the number of the students involved is 761, including participants of the 1 night and 2 days camps in the Daegu National Science Museum. The newly developed planetarium lesson is comparable to the previous classroom lesson of which topics are cardinal points, constellation, and the rotation of the earth. Test items were developed to evaluate the understanding of the astronomical concepts. The study was conducted based on the pre- and post-test with non-equivalent groups design comparing classroom and planetarium lessons. The results of this study are as follows. First, planetarium lesson is more effective for understanding astronomical concepts such as the cardinal points, earth's rotation, and the constellation than classroom lesson. Second, planetarium has a positive effect irrespective of gender and previous knowledge. Third, planetarium for high school students has the same effect as additional observation activities followed by the classroom instruction. Therefore, planetarium can be used as an alternative, effective tool when night observation is not available. In summary, planetarium is an effective tool that helps students to understand the astronomical concepts.

• 한국해양학회지
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• v.30 no.3
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• pp.184-196
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• 1995

The line-SW is located in the mouth of Gomso Bay (20 Km long and 5-8 Km wide),west coast of Korea. This area is composed of sand flat, mud flat, sand shoal and chenier, The difference of physical, geological and geomorphic conditions in subenvironments of the bay may control and produce distingtive foraminiferal populations and assemblages. This study investigates whether five a priori subenvironments (five local zonations) in Gomso-Bay tidal flat can be distinguished from each other on the basis of total (living plus dead) foraminiferal assemblages. Seventy-four species (67 benthic; 7 planktonic) were recorded in total assemblages of surface sediments from 10 stations. Ammonia beccarii tepida, Discorbis candeiana, Elphidium etigoense and Eponides nipponicus were most dominant species in living and total assemblages. The relative abundance (%) of living population was high at upper flat and decreased from upper to lower flat. The low percentages of living populations in middle to lower flat are probably influenced by the decreasing reproduction of foraminifera caused by high energy condition and addition of dead species from offshore. The occurence of planktonic foraminifera in middle to lower flat (5.3∼6.6%) indicates introduction of planktonic foraminifera from offshore by storm and/or tidal current. The relatively high numbers of species in lower middle to lower flat are probably caused by a mixing of faunas from these areas and offshore. The high numbers of total individuals per 50 ml of sediment in upper flat indicate that this area is a relatively stable environment where waves and currents are protected by the chenier. Five biofacies of the total foraminiferal assemblages were established on the basis of dominant species (those representing more than 20% of the total assemblages in any station) in the five a priori subenvironments recognized along the Line-SW transect in Gomso-Bay tidal flat. Five biofacies are potentially useful in paleoenvironmental interpretation in late Quaternary Gomso-Bay tidal deposits.

• Korean Security Journal
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• no.11
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• pp.159-181
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• 2006

This study is concerned on Why The Certified Security certification is needed and How to control the security quality to get better service to the clients. Theses days are required The Certified Certificate in all the industry. And in this point of view, the certified certificate is a kind of confirmation by an authority to the person who has how much special knowledge and practice in a certain field. Moreover, in the functionalism society the certified certificate system would be very positive effect to the related industry and society as official measurement by an authority. The security is freedom from fear and anxiety. Which means the security can not be operated in isolation from citizen's safe-living expectation, and which is also dealing with valuable human being's life. For getting the better purpose the security industry employees should have more organized special training and education. As my understanding the certified certificate exam system is the confirmation by an authority, the certified certificate is only neutral evidence to get the confidence and credit from the clients. In this point of view the core point is How to control The Certified Certificate by a credied authority.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.23 no.1
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• pp.23-30
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• 2012

Objectives : This study was conducted to investigate the prevalence of victims of bullying and the demographic characteristics of victims, and their related psychopathology, in a Korean nationwide sample of youths in middle and high school over a one month period. Methods : During the autumn of 2009, students in the 7th to 12th grades at 23 secondary schools participated in a nationwide, cross-sectional study. The study subjects completed the Adolescent Mental Health and Problem Behavior Screening Questionnaire-II (AMPQ-II) and Symptom Checklist-90-Revision (SCL-90-R). Based on the data acquired, descriptive statistics, correlation coefficients and multiple logistic regression analysis were performed. Results : Among the 3364 participants, 2272 (67.54%) completed the questionnaire. The prevalence of victimization was 28.9%. Male gender was positively associated with victimization, and grade level was negatively related to victimization. The AMPQ-II bullying score (Factor 4) was significantly (p<.001) and positively correlated to the AMPQ-II student total score (r= 0.50), Worry and thought (Factor 1 ; r=0.38), Mood and suicide (Factor 2 ; r=0.31), Academic and Internet-related problems (Factor 3 ; r=0.24), Rule violations (Factor 5 ; r=0.23), and AMPQ-II teacher total score (r=0.11). Somatization (r=0.23), Obsessive-compulsive behavior (r=0.24), Interpersonal sensitivity (r=0.30), Depression (r=0.33), Anxiety (r=0.26), Hostility (r=0.30), Phobic anxiety (r=0.22), Paranoid ideation (r=0.36), and Psychoticism (r=0.31) results from the SCL-90-R were also found to be positively related to the AMPQ-II bullying score, and remained significant after adjusting for age and gender. A total of 26% of the victims reported suicidal ideations as compared to 9% of non-victims over the month prior to the evaluation ($x^2$=119.595, df=1, p<.001). The multiple logistic regression analysis indicated that the AMPQ-II bullying score significantly increased the risk of suicidal ideation [Exp(b)=1.55, df=1, p<.001] after adjusting for age and gender. Conclusion : School bullying was highly prevalent among Korean middle and high school students. This study provided strong evidence that suicidal ideation and psychopathology were serious problems among the victims of bullying.

• Journal of Korean Society of Forest Science
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• v.89 no.1
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• pp.24-32
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• 2000

We investigated the patterns of soil horizon evolution and its water distribution on three different forest stands covered with Larix leptolepis, Pinus koraiensis, and Qercus mongolica on the Experimental Forest of Kyunghee University, located in Kwangju, Kyunggi-Do. Compared to the properties of depths of O and A horizons evolved on the Pinus koraiensis stand, the depths of O and A horizons on the forest stands of Larix leptolepis and Qercus mongolica were shallower, indicating that the soil horizon were deeply influenced by geographical characteristics, its erosive and sedimentary distinction, vegetation cover and its population density. And the bulk densities of the sites selected were lower in the high slope gradient than that in the lower slope gradient at the same depth of soil profile. Therefore, the changes of the soil bulk densities were closely related to the soil organic matter and the vertical transport of soil particle throughout soil depths. On the other hand, the bulk density and organic matter content in soil can influence the water transport phenomena, resulting in decrease of the hydraulic conductivity as the increase in the bulk density, while the organic matter can not affect the hydraulic conductivity on the soil surface layer. For a rainfall infiltration characteristics from a lysimeter experiment established on the stand of Larix leptolepis, the bulk density and slope gradient strongly influenced the vertical transport of water, as well as the lateral movement of rainfall. Conclusively, the characteristics of water movement and distribution in the forest stand can be determined not by the geographical factor such as slope gradient but also by the bulk density and organic matter content remained in soils.

• Journal of Global Scholars of Marketing Science
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• v.18 no.4
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• pp.217-244
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• 2008

Consumers' overall satisfaction on a specific library use is inferred to be primarily accrued from their performance perception and use satisfaction on the library information service system as recent information technology is being rapidly improved and more libraries are being equipped with advanced information technologies. However, prior research has been conducted only on general library service quality and visitors' satisfaction, leaving the important aspects of visitors' library use and information performance perception. Thus, the objectives of this research are to examine the effect of library use patterns such as general visit for book reading and more professional information search, coupled with service quality, on the library users' performance perception on the information system that in turn, affects library use satisfaction on the same information system. More specifically, this study examines whether library visitors perceive differenltly the information system performance according to their library use patterns such that professional library users may have less positive on information system service due to their higher expectation or more positive perception on it due to variety of information uses and positive judgment on advanced information system. Next, three dimensions of service quality, consisting of interaction, outcome, and physical evidence quality in visitors' library use situations, are hypothesized to affect performance perception on library information system. Thirdly, the performance perception on library information system is hypothesized to influence the system use satisfaction while these two constructs are to affect visitors' overall satisfaction. we develop the following research model in accordance with the above theoretical reasoning. All variables used in this study(General Use Patterns, Professional Use Patterns, Interaction Quality, Outcome Quality, Physical Evidence Quality, Information Performance Perception, Information Use Satisfaction, Overall Satisfaction) were defined operationally based on the underlying prior studies. A survey was conducted with prepared questionnaires to about 400 visitors of a specific university library. Among them, 353 proper questionnaires were finally used for the analyses. Two-step approach was used to test the hypotheses. First, confirmatory factor analysis was conducted to guarantee the validity and reliability of variables. The results showed that all variables had not only convergent and discriminant validity, but also reliability. Then, research model was examined with a structural equation using LISREL 8.30 version. The fitness of the research model was found to be within the acceptable level. The findings of this study are as follows. The professional library use pattern was found to affect the users' performance perception on the library information system while the general library use pattern was not. Second, three dimensions of service quality (interaction, outcome, physical evidence) were found to influence the information system performance respectively while none of them was not to information use satisfaction. Third, library users' performance perception on the information system operation was found to affect the information system use satisfaction, both of which also influence users' overall satisfaction of the library. The findings of this study suggest that contemporary libraries strengthen their advanced information system operation in a way of user orientation and more importantly maximize their visitors' utilization of information system, accompanying proper material and various program development. This study conceptualized the new constructs of library users' performance perception on the information system and information use satisfaction which could better explain library users' overall satisfaction. Thus, furture study related with library service could utilize the constructs of information system performance and satisfaction as well as the variety of library use patterns in the users' viewpoints.

• Journal of Korean Society of Forest Science
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• v.82 no.2
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• pp.139-151
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• 1993

The virgin forests on and around Sungin-bong in Ulreung-do, an island situated between the Korean peninsula and Japanese archipelago, were investigated phytosociologically. They were classified into two communities, i.e. Fagus crenata var. multinervis - Majanthemum dilatatum community and F. crenata var. multinervis - Sasa kuriensis community. The former was subdivided into several units ; Acer takesimense - Allium victorialis var. platyphyllum group, including Tsuga sieboldii - Taxus cuspidata var. tatifolia subgroup and a typical subgroup, and Acer mono var. savatieri - Rumohra standishii group, including Dystaenia takeshimana subgroup and a typical subgroup. The other was subdivided into two subunits ; Acer okamotoanum group and a typical group. It was estimated that this area was orginally covered with beech and maple dominated forest vegetation and with Machilus dominated forest or bamboo forest. However, in these days, The natural vegetation of it has been destroyed and in future, may also be disturbed gradually by human activities. Judging from the coincidence method, the structure and distribution of the forest communities was more related to altitude than to topography. The phytomass, based upon the basal area of each community to $100m^2$ showed that Acer mono var. savatieri - Rumohra standishii group ($BA=7574.1cm^2$, $P=9,882,058cm^3$) haved the largest value and Tsuga sieboldii - Taxus cuspidata var. latifolia subgroup($BA=2126.3cm^2$, $P=1,746,755cm^3$) showed the smallest value. The flora of the vascular plants collected from this area consists of 71 families, 187 genera, 243 species, 1 subspecies, 44 varieties, 6 forms and 294 taxa in total.

• Journal of the Korean association of regional geographers
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• v.6 no.3
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• pp.153-168
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• 2000

An estuarine marsh is semi -inclosed inlets, located between coastal and terrestrial environment. The sediment transport by river and tide through tidal river and vertical accretion by sediment accumulation are important processes in estuarine marsh. An analysis of the vertical accretion rate at various time scale is important work for understanding and managing coastal environments. The purpose of this study is to determin the spatial characteristics of vertical accretion rate in an estuarine marsh, Sunchon Bay, in the southern coastal region of Korean peninsula. The methods of analysis are sedimentation rate by individual tidal cycle, annual accretion rate, concentration of total suspended load in water column. Spatial characteristics of sedimentation rate by individual tidal cycle was investigated using 30 filter paper traps. Sedimentation rate by individual tidal cycle at levee edge was higher than that at back marsh. The sedimentation rate decreased with distance from estuarine front. Levee effect and proximity to the turbidity maximum zone result in a higher sedimentation rate in the levee edge. There is a weak relation-ships between tidal regime and sedimentation rate by individual tidal cycle. Spatial cahracteristics of annual accretion rate was investigared using 30 artificial marker plots. Annual accretion rate at back marsh($1.5{\sim}3.5cm/yr$) was higher than that at tidal river levee edge($0.8{\sim}3.0cm/yr$). Total suspended load (TSL) concentrations in water column also indicate this spatial characteristics of annual accretion rate. TSL concentration in water column leaving the vegetation part dramatically decreased. There is a very strong relationship between the concentration of suspended load and accretion rate. These results indicate that annual accretion rate is controlled by vegetation cover and proximity to the turbidity maximum zone. This difference of spatial characteristics of vertical accretion rate ar various time-scale was due to the fact that surface sediment of levee edge was eroded by tide and other factors. The major findings are as follows. First, the spatial characteristics of vertical accretion rate are different from various time-scale. Second, the major mechanism for the vertical accretion rate in this region is suspended load trapping by vegetation. Third, this region is primarily a depositional regime over the time-scale of the present data Fourth, this estuarine marsh is accreting at rates beyond other area.

• Childhood Kidney Diseases
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• v.11 no.2
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• pp.239-246
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• 2007

Purpose : The progressive deterioration of renal function in children can impose a serious and lifelong impact on their lives. The ultimate goal in the management of children with chronic kidney disease(CKD) is to prolong survival, to prevent complications, and to promote growth and neurodevelopment. The aim of this study is to investigate the risk factors for the decline of renal function in pediatric CKD patients. Methods : Data from patients who met the criteria for the Kidney Disease Outcomes Quality Initiative(K/DOQI) CKD stage 2 to 4 between August 1999 and March 2007 were retrospectively analyzed. The estimated glomerular filtration rate(eGFR) was calculated by the Schwartz formula, using serum creatinine levels and height. We calculated the annual eGFR change from the difference between the baseline eGFR and the last eGFR divided by the duration(years) of the follow-up period. We analyzed the association between the annual eGFR change and factors such as age, gender, K/DOQI stage, underlying renal disease, serum calcium, and inorganic phosphorous during the follow-up period. Results : Sixty one children(44 boys & 17 girls) were enrolled. The age at entry was $7.1{\pm}4.7$ years. The annual eGFR change was $-1.2{\pm}11.9 mL/min/1.73m^2/year$. Our study showed that older age(P=0.005). hypocalcemia(P=0.012), and hypenhosphatemia(P=0.002) were significantly related to more rapid decline in renal function. Conclusion : In pediatric CKD, older age, hypocalcemia and hyperphosphatemia are related to more rapid deterioration of renal function.