• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.185-196
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• 2012

The fish community within the lake and 5 tributaries of Lake Chungju in spring and autumn, 2009 was surveyed. In this study, the total 128,506 individuals were collected belonging to 11 families 29 genera 34 species. The most dominant species was Squalidus japonicus coreanus that account for 91.6% of population and 49% of biomass of fish community. In the point of population, dominant species were small-sized species, which became the prey of big-sized predatory species. In the point of biomass, dominant species were predatory species which were large-sized. The most dominant species in lacustrine area was S. japonicus coreanus which accounted for 92.2% of total population and 49.1% of total biomass. The most dominant species of tributary streams was Tridentiger brevispinis which accounted for 66.4% of total population and 55.1% of total biomass. The site of C3 in lacustrine area and Dongdal-cheon in tributary streams collected the most number of species. Through ecological health evaluation of five tributary streams using 8 metric index of biological integrity (IBI) model, two streams (Dongdal-cheon, Kwang-cheon were evaluated as, "B", "good" condition, and Jangsung-cheon obtained grade C indicating "Fair" condition, Jecheon-cheon obtained grade D indicating "Poor" condition based on IBI model. Lepomis macrochirus which was designated as a domestic ecosystem-disturbing alien species with wide food niche have shown tendency to increase the number of individuals since 1991 indicating the adverse effect on not only fish community but also aquatic ecosystem food web of Lake Chungju.

• Journal of Surface Science and Engineering
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• v.27 no.4
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• pp.193-206
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• 1994

A wear behavior of electroless (Ni-P-X, X: SiC, $Al_2O_3$, Diamond) composite coating layers, formed under various conditions on commerical grade low carbon steel, has been investigated using Taber abrasion tester and scanning electron microscope. Several factors, which are type of particles, co-deposited content, particle size, distribution of particles and heat-treatment, influenced the wear resistance. The wear resistance of the composited coating layers after heat-treatment at $400^{\circ}C$ for 1 hr was increased 70 times with diamond, 15 times with SiC and 8 times with $Al_2O_3$, compared with the electroless nickel plating layer without heat-treatment.

• Journal of the Korean Society for Heat Treatment
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• v.12 no.1
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• pp.31-39
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• 1999

In the present study, oxidation behavior of 304 and 316 stainless steels was investigated. After solution treatment, specimens were polished up to $1{\mu}m$ $Al_2O_3$ grade and then subjected to oxidation treatment in dry air. The range of temperature was used for oxidation treatment at $300^{\circ}C{\sim}500^{\circ}C$ and TEM was used for analyzing the components and structure of oxide film. Also, these results were compared with the results of ESCA and TG. According to the results of TEM analysis, it was found that Cr oxide film was formed on top of the surface after room temperature oxidation but amorphous Fe oxide was formed on top of the surface and polycrystalline $(Cr,Fe)_2O_3$ was formed below the amorphous Fe oxide layer after $500^{\circ}C$ oxidation treatment. The oxidized specimens at $500^{\circ}C$ showed that 316 stainless steel resists more strongly to grain and grain boundary oxidation than 304 stainless steel. These results suggested that Mo component resolved in 316 stainless steel matrix suppressed the formation of Cr carbide which may results in local Cr deplete area.

• Journal of the Korean Society of School Health
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• v.25 no.1
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• pp.122-132
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• 2012

Purpose: The purpose of this study is to determine the effectiveness of cooperative learner-centered methods of sex education. Methods: This study was carried out on 5th grade elementary school students in D-district. Nine classes were divided into 3 groups using each different teaching methods: group A (a cooperative learning), group B (a lecture) and group C (a control group for a comparison). The study period was from Oct. 17 to Dec. 2 in 2011. Both groups A and B received sex education lessons for 40 minutes for 4 weeks and were tested their sex knowledge and attitude to compare the differences. Results: The scores of sex knowledge for all three groups were increased and their sex attitude was increased as well. The points of sex knowledge between pre and post test in group A are greater than the group B's. Thus, the cooperative learning approach with Group A was more effective to improve student's sex knowledge. But the difference between the sex attitude scores was not statistically significant. Group A and B showed a positive improvement in both their sex knowledge and attitudes compared with the control group. Conclusion: This experiment shows that an active teaching methods is more effective to improve student sex knowledge than a passive approach. Thus, a cooperative learning method results in increases of both student's sex knowledge and interests in learning sex education. It needs to develop more diverse teaching methods and programs on sex education that are more systematic and tailored.

• Journal of Korean Neurosurgical Society
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• v.60 no.5
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• pp.534-539
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• 2017

Objective : Patients with hematological malignancies frequently encounter spine-related symptoms, which are caused by disease itself or process of treatment. However, there is still lack of knowledge on their epidemiology and clinical courses. The purpose of this article is to review clinical presentations and surgical results for spinal involvement of hematologic malignancies. Methods : From January 2011 to September 2014, 195 patients (98 males and 97 females) suffering from hematological malignancies combined with spinal problems were retrospectively analyzed for clinical and radiological characteristics and their clinical results. Results : The most common diagnosis of hematological malignancy was multiple myeloma (96 patients, 49.7%), followed by chronic myeloid leukemia (30, 15.2%), acute myeloid leukemia (22, 11.2%), and lymphoma (15, 7.56%). The major presenting symptoms were mechanical axial pain (132, 67.7%) resulting from pathologic fractures, and followed by radiating pain (49, 25.1%). Progressive neurologic deficits were noted in 15 patients (7.7%), which revealed as cord compression by epidural mass or compressive myelopathy combined with pathologic fractures. Reconstructive surgery for neurologic compromise was done in 16 patients. Even though surgical intervention was useful for early paralysis (Frankel grade D or E), neurologic recovery was not satisfactory for the progressed paralysis (Frankel grade A or B). Conclusion : Hematological malignancies may cause various spinal problems related to disease progression or consequences of treatments. Conservative and palliative treatments are mainstay for these lesions. However, timely surgical interventions should be considered for the cases of pathologic fractures with progressive neurologic compromise.

• Journal of Animal Environmental Science
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• v.11 no.2
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• pp.77-88
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• 2005

The effect of different particle sizes of scoria inclusion in weanling-growing-finishing diets on growth performance and carcass quality was investigated in this study. Treatments were the control (basal diet), and 3 scoria treatments with different partical sizes (500, 1,000, 1,700 ${\mu}m$, respectively) in which $3\%$ of basal diet was replaced by scoria. This study was carried out for 143 days using 84 pigs. Each treatment has 3 replicates (4 gilts and 3 barrows per pen). 1. During nursery period, all scoria treatment levels showed poor Average daily gain (ADG) and feed efficiency compared to the control. During growing period, The ADG and feed efficiency of pigs fed the $1,000\;{\mu}m$ swine treatment tended to improve. For the whole growth period (d 0-143), $1,000\;{\mu}m$ scoria treatment showed significantly higher (P<0.05) ADG and feed efficiency than the $1,700\;{\mu}m$ scoria treatment. 2. Carcass weight was higher in all of scoria treatment levels Either the control (P<0.05), while backfat thickness was unaffected among treatments. Carcass Grade A or B grade appearance was more evident in all of scoria treatments compared to the control. 3. Hunter L value was numerically higher in the control while there was no significant differences among the control, $1,000\;{\mu}m$ scoria and $1,700\;{\mu}m$. Hunter a value was highest (P<0.05) in $1,000\;{\mu}m$ scoria, while Hunter b values were not influenced by the scoria treatment levels. 4. The different scoria treatment levels reduced N and P excretion. For growing period, $1,000\;{\mu}m$ scoria was most efficient in reducing N excretion, while during the finishing period, $1,700\;{\mu}m$ scoria was the best. The P excretion was affected by scoria particle size during growing-finishing periods rather than weanling period. The above findings indicated that the inclusion of different scoria partical sizes in nursery diet resulted to adverse effects on growth performance in contrast to the growing finishing diets wherein the growth performance and carcass quality were not affected. Finally, scoria regardless of particle size proved to be effective in reducing N and P excretion and can be considered an environment friendly mineral source for growing-finishing hog diets.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1638-1642
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• 2006

An experiment was conducted to elucidate the effect of graded levels of vitamin $D_3$ in White Leghorn (WL) layer breeders on egg production, shell quality, hatchability of eggs and juvenile performance of offspring during their late laying period (72-88 wk). White Leghorn breeder females were randomly divided into 5 groups of 50 each and were housed in individual California cages in an open-side housing system. Considering birds in five cages as a replicate, 10 such replicates were randomly allotted to each treatment. A basal diet was formulated containing all the nutrients as recommended for WL layers except vitamin $D_3$, which served as control. Another, four diets were formulated by supplementing graded levels of feed grade crystalline cholecalciferol to the basal diet that contained 300, 600, 1,200 and 2,400 ICU of vitamin $D_3$ per kg. Each diet was offered ad libitum to one of the above five treatment groups. The egg production, egg weight, daily feed consumption and the feed intake per dozen eggs or kg egg mass of the birds fed diet without any supplemental vitamin $D_3$ was comparable with those of supplemental groups. Similarly, the level of vitamin in the diet did not have any effect on any of the above parameters. However, the specific gravity of eggs laid by the birds fed the diet without supplemental vitamin $D_3$ was comparable with either 600 or 2,400 ICU supplemental groups but significantly higher when compared to the 300 and 1,200 ICU groups. The egg -shell breaking strength was significantly lowered in the 600 ICU supplemental groups as compared to the strength of other dietary groups. The Haugh unit, egg shell weight, shell thickness, tibia breaking strength, bone ash and calcium content were not influenced by vitamin $D_3$ concentration in the diet. Serum Ca concentration was influenced by vitamin $D_3$ level in the diet. The serum Ca concentration of birds fed either control or the vitamin supplemented diet up to 1200 ICU/kg diet was comparable. However, increasing the concentration of vitamin $D_3$ to 2,400 ICU/kg diet significantly enhanced the concentration of Ca in the serum, which was significantly higher compared to other dietary groups. The serum concentration of P and protein, however, was not influenced by level of vitamin $D_3$ in the diet. Neither fertility nor hatchability was influenced by vitamin $D_3$ concentration in the diet. Feeding a vitamin $D_3$ deficient diet or supplementation of vitamin to hens did not have any influence on their progeny chicks. It can be concluded that dietary supplementation of vitamin $D_3$ may not be essential for optimum production, shell quality, hatchability, and juvenile performance of WL breeders during 72 to 88 weeks of age.

• Journal of Korean Foot and Ankle Society
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• v.26 no.2
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• pp.66-70
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• 2022

Purpose: A group of patients who were hospitalized for diabetic foot ulcers was classified according to the University of Texas Staging System for Diabetic Foot Ulcers, and we attempted to evaluate whether this staging system could be a criterion for treatment success using vacuum-assisted closure (VAC) technique. Materials and Methods: A total of 32 patients were diagnosed with diabetic foot ulcers according to the University of Texas Staging System for Diabetic Foot Ulcers. Of these, 24 patients who were evaluated as stage B according to the staging system were classified as Group 1, and 8 patients in stage D were classified as Group 2. After applying VAC, the treatment success rate was compared by evaluating the size and severity of ulcers between the two groups. Results: The grade of granulation after VAC was on average 3.75±0.53 in Group 1 and 2.25±0.71 in Group 2. There was better granulation after VAC application in Group 1 (p<0.01). The success rate of the treatment was 22 cases (91.67%) in Group 1 and one case (12.5%) in Group 2. Thus there were statistically significant differences in the success rate of treatment between groups 1 and 2 (Pearson's chisquare test, p=0.01; odd ratio 77.00, 95% confidence interval [CI] 1.26~14.66; relative risk 4.30, 95% CI 1.26~14.66). Conclusion: These results suggest that there was a higher success rate of treatment with VAC in stage B patients. The University of Texas Staging System for Diabetic Foot Ulcers can thus be an index for applying VAC to patients with infective diabetic foot ulcers.

• Journal of Internet Computing and Services
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• v.21 no.4
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• pp.77-85
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• 2020

The purpose of this study is to explore the changing trajectory of using educational media through longitudinal data analysis. We categorize the feature of using educational media as usage for learning, usage for information, and usage for the game. We explore the longitudinal changing patterns of usage for learning, usage for information, and usage for the game by LGM(Longitudinal Growth Modeling). We also find the gender difference between these longitudinal changing trajectories. We used 3,499 samples of KYPS middle school second-grade panel data. We found these results: (a) Both usage for learning and information are statically significant variability in initial level and rate of change. Both of the changing trajectories have increased. (b) Girls have a higher rate of the change both in the usage of learning and information than boys over time. (c) There is a statistically significant individual variability in initial levels and rate of change in the usage of the game over time. (d) Boys have a higher rate of initial value than girls in the usage of games, but there is no significant difference in the rate of changing trajectories.

• The Korean Journal of Elementary Counseling
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• v.10 no.2
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• pp.151-165
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• 2011

This study aims to demonstrate how well SCM analysis, which indicates social cognitive map of categorizing peer subgroups of elementary school students, corresponds with that of teachers. To do this, the subject of this study includes two classes of the 3rd and the 5th grade students in D elementary school in B-gu, Busan city. Over 30 students of each gender in each grade were surveyed with social network questionnaires to collect data. The result of the social network survey was analyzed by SCM 4.0 program to categorize peer subgroups within each class. The categorized peer subgroups were reported to the class teacher. Based on the report, the class teachers observed peer subgroups in classes. After the teachers observed and categorized the students into several peer groups, an analysis was conducted to compare the peer subgrouping by students with that by teachers. The result showed the two were 80% correspondent to each other regardless of gender and grade. If interobserver reliability stays within the range of 80-100%, it is considered reliable. And this leads to the conclusion that peer subgrouping by students' cognition and that by teachers' observation can be regarded quite corresponding. In conclusion, peer subgrouping through SCM is significant when peer subgrouping Korean children, and it appears to be more significant when analyzed considering different variables including gender and grade. Peer subgrouping by girls is shown to be more accurate than that by boys.