• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.222-224
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• 1975

Three strains of common carp, i. e. , Israeli carp, red-and-white, and golden strains, were stocked in the same pond, and their growth rates were compared with following results: From August 12 to November 21 in 1975, fingerlings of the three strains of common carp, Cyprinus carpo, each weighing about 0.5 g with total length of 2 to 3 cm, were stocked. The pond had an area of $316m^2$ with a mean water depth of 55cm, and the bottom was covered with a 20 to 30 cm thick layer of silt containing a considerable amount of decaying organic materials. Feed given was prepared with equal amounts of fish meal and polished barley, of which, in addition, $10\%$ green grass and $1\%$ table salt were mixed together when prepared into paste feed using a chopper after boiling the barley. Total protein content of the feed was $34.9\%$ in dry state with $5\%$ moisture content. Total feed given was 30.08 kg calculated in dry state to produce 20.588 kg of the common carp fingerlings, thus the feed coefficient being 1.51. By strains, the harvested Israeli carp ranged 98 to 311g each with a mean weight of $172.69g(100\%)$, red-and-white strain 15 to 318g with mean of $104.1g(60.3\%)$, and the golden strain 30 to 268g with mean of $128.7g(74.6\%)$. During the rearing season mean water temperature was $23.9^{\circ}C$ and the assumed main growth period with the water temperature above $15^{\circ}C$ was, upto the end of October, for 80 days with a mean water temperature of $23.9^{\circ}C$. Taking this main growth period as the basis for growth rate analysis, the mean daily increments, expressed as the attained body weight in times of the starting weight, become 1.075786 times (or the Israeli strain, 1.06901 times for the red-and-white strain, and 1.07185 times for the golden strain.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.8-17
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• 2000

The BER performance and the capacity variation of a microcell due to power control error(PCE) is analyzed on service types(data and voice, respectively) for the reverse link of an overlaid cell CDMA system. The procedure of analysis is followed as: First, we calculate BER performance according to PCE. Next, we find the minimum SNR for voice service, BER=TEX>$10^{-3}$, and data service, BER=TEX>$10^{-5}$. Then, according to the calculated SNR, we find the maximum capacity of a microcell and macrocell and the capacity of a microcell where interference is considered is found and analyzed with that in perfect power control. We get to the results as follows. The BER performance in 1 dB PCE is similar to that in perfect power control, however, with a increase in PCE, the BER performance is largely degraded. In terms of capacity, it is shown that if the PCE is equal or less than 2 dB, the effect of the PCE on voice service is more than that on data service, but if the PCE is equal or more than 3 dB, effect of the PCE on data service is more than that on voice. Besides, if the PCE is equal or less than 2 dB, both PCE and interference should be considered to calculate the capacity of a microcell, but if the PCE is equal or more than 3 dB, interference can be negligible since the effect of PCE is much stronger than that of interference. Therefore, the microcell should be located where $R_d$, the ratio of a microcell to a macrocell radius, is equal to 0.1, and d, the ratio of the distance between a microcell and a macrocell to the macrocell radius, is equal or more than 0.5, in order to obtain a appropriate microcell capacity against interference. If $\sigma$ is adjusted to less than 2 dB, we may get equal or more than 70% of the maximum microcell capacity.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.4
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• pp.258-270
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• 2012

Purpose: Use of inappropriate statistical methods may lead to incorrect conclusions and a waste of valuable resources. The goal of this study was to assess the frequency and the types of several common statistical errors in the published articles of the Journal of the Korean Academy of Prosthodontics (JKAP) for a 5-year period. Materials and methods: Of 336 articles in the JKAP published from 2006 to 2010, 255 articles using statistics were reviewed and classified by statistical method and year. The frequency and types of the statistical methods were examined, and the statistical errors were evaluated by the appropriateness of the experimental design, assumption check, independent outcomes, proper sample size and suitable use of statistical method. Statistical guidelines were completed based on the appropriateness. Results: Of the 255 articles using statistics, 193 articles (75.9%) used inferential statistics and 153 articles used SPSS statistical software (60.0%). Of the articles using inferential statistics, the three most frequently used statistical methods were ANOVA (41.5%), t-test (20.0%), and the nonparametric method (16.9%). The average rate of statistical errors was 61.2 percent, similar to the rate reported by several studies completed for the medical journal. Conclusion: After the whole analysis of the difference among the groups, post-hoc tests for the pairwise comparisons are required. The optimal sample size calculation is an essential part of this study protocol. To minimize the occurrence of statistical errors, statistical guidelines were developed according to each statistical test procedure and will contribute to the academic improvement in the JKAP.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.206-214
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• 2005

Heterogeneously-catalyzed oxidation of aqueous phase trichloroethylene (TCE) over supported metal oxides has been conducted to establish an approach to eliminate ppm levels of organic compounds in water. A continuous flow reactor system was designed to effect predominant reaction parameters in determining catalytic activity of the catalysts for wet TCE decomposition as a model reaction. 5 wt.% $CoO_x/TiO_2$ catalyst exhibited a transient period in activity vs. on-stream time behavior, suggesting that the surface structure of the $CoO_x$ might be altered with on-stream hours; regardless, it is probable to be the most promising catalyst. Not only could the bare support be inactive for the wet decomposition reaction at $36^{\circ}C$, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Very low TCE conversion appeared for $TiO_2$-supported $NiO_x$ and $CrO_x$ catalysts. Wet oxidation performance of supported Cu and Fe catalysts, obtained through an incipient wetness and ion exchange technique, was dependent primarily on the kinds of the metal oxides, in addition to the acidic solid supports and the preparation routes. 5 wt.% $FeO_x/TiO_2$ catalyst gave no activity in the oxidation reaction at $36^{\circ}C$, while 1.2 wt.% Fe-MFI was active for the wet decomposition depending on time on-stream. The noticeable difference in activity of the both catalysts suggests that the Fe oxidation states involved to catalytic redox cycle during the course of reaction play a significant role in catalyzing the wet decomposition as well as in maintaining the time on-stream activity. Based on the results of different $CoO_x$ loadings and reaction temperatures for the decomposition reaction at $36^{\circ}C$ with $CoO_x/TiO_2$, the catalyst possessed an optimal $CoO_x$ amount at which higher reaction temperatures facilitated the catalytic TCE conversion. Small amounts of the active ingredient could be dissolved by acidic leaching but such a process gave no appreciable activity loss of the $CoO_x$ catalyst.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.319-325
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• 2018

The aim of the present study was to determine the influence of different fertilizer combinations on the growth, yield, and fruit quality of 'Duke' blueberry cultivar and the water quality of growth medium. The experiment was carried out with three year old 'Duke' blueberry bushes which were cultivated in containers ($60{\times}80{\times}40cm$) filled with 130 L peat moss and 40 L pearlite (v/v). Sawdust was used as the mulch in growth containers. Three different fertilizer combinations (FC) i.e., FC-1 consisted with standard solution, FC-2 consisted with nitrogen reduced by 10% from FC-1, and FC-3 consisted with nitrogen reduced by 20% from FC-1 were tested while, the ground water used as the control. The effects of different fertilizer combinations on shoot diameter, shoot length, number of shoots, leaf length, SPAD value (the relative content of chlorophyll), berry weight, soluble solids content, titratable acidity, and yield per bush in 'Duke' blueberry were examined. Also, the effects of different fertilizer combinations on pH, EC, $NH_4$ and $NO_3$ in 'Duke' blueberry growth medium were monitored. The highest pH and lowest EC, $NH_4$ and $NO_3$ in growth medium was recorded with control treatment during the experiment period. The maximum shoot diameter (3.7 mm) and shoot length (35.7 cm) was recorded for the FC-1. Highest number of shoots (47%) were recorded from 'Duke' blueberry bushes supplemented with FC-1 compared to other treatments. The fertilizer combinations supplemented with nitrogen showed significant influence on leaf length and SPAD value compared to control 'Duke' blueberry bushes. However, the fruit quality attributes, i.e., berry weight, soluble solids content, and titratable acidity were not significant different among fertilizer treatments. The significantly highest yields per bush were recorded for FC-1, FC-2, and FC-3, as 2.2, 2.9, and 2.7 kg, respectively compared to control (0.2 kg). Although, the FC-1 was supplemented with highest nitrogen content it resulted low yield per bush while having high number of shoots and vigorous growth.

• Sijohaknonchong
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• v.42
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• pp.7-28
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• 2015

This article defines sijo's musicality in two ways and verifies how musicality is shown in modern sijo with some examples. First, the first metre of a song's fourth part, that is, the sijo's jongjang, should include a reverse of its poetic image. A song consists of five parts. Each part is sung as a part of the song, that is, the sijo's dimetre, trimetre, or tetrametre, but its fourth part is sung as the monometre which is the first metre of its jongjang. This is because the first metre of a sijo's jongjang forms the axis of the reverse in its poetic image, and when this works properly, it can maintain musicality as a sijo. Second, a sijo's tetrametre and sijo-chang's gak should correspond as the same value along with the completion of its meaning. If a sijo does not keep the metre, each part's completion of meaning and also the sijo-chang's gak become problematic, so it is impossible to perform sijo-chang. Only when each part's completion of meaning and the gak of the metre correspond to each other as the same value, the sijo can maintain its musicality. Next, the study verifies how musicality is shown in modern sijo. This was examined through the examples of gyeol-metre and yangjang-sijo in dan-sijo that cannot form any tongsa madi, arrangement of syllable units beyond metres, or the examples of loose reverse of meaning in a transitional phrase. The two kinds of musicality presented by this author have already been proved with old sijo. However, modern sijo has been created mainly centering around its image, so such musicality has been ignored and sijo's identity has been damaged seriously. In sijo, musicality gives life. If modern sijo is created mainly around its image, it can never be called as sijo unless it has musicality. Although modern sijo is not performed as music, it should be equipped with the form to be performed as a chang. This is how sijo can maintain its musicality. It is thought that now is the time to recognize modern sijo as the matter of communication between sijo-chang and sijo literature, not just as the combination of sijo-chang and sijo literature.

• The korean journal of orthodontics
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• v.30 no.4 s.81
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• pp.441-452
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• 2000

The present studies were performed to investigate the interaction of $17{\beta}$-estradiol and human growth hormone(hGH) on the proliferation of human periodontal ligament(WDL) cell. The independent effects of $17{\beta}$ estradiol and hGH on hPDL cell proliferation were investigated and the effects of hGH on hPDL cell proliferation after $17{\beta}$-estradiol pre-treatment were also investigated. Lastly, the change of hGH receptor expression in hPDL cell after $17{\beta}$-estradiol pre-treatment were investigated. The obtained results were as follows; 1. The treatment of $17{\beta}$-estradiol or hGH had no significant effects on hPDL cell proliferation. 2. After pre-treatment of $17{\beta}$-estradiol, hGH stimulated the proliferation of the hPDL cell, regardless of hHG concentration. 3. Although there was not hGH receptor in the hPDL cell, hGH receptors were expressed in hPDL cell after more than 6 hours pre-treatment of $17{\beta}$-estradiol. 4. The effect of hGH on hPDL cell proliferation was related to the hGH receptor expression. $17{\beta}$-estradiol pre-treaaent contributed to the hGH effects on the hPDL cell by stimulating hGHR expression.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.5
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• pp.285-292
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• 2008

To investigate the effect of tillage methods on the silage barely growth and the soil environment in paddy field, liquid pig manure(LPM) was applied after harvesting rice at Jisan series soil for 2 years. Five plots, a LPM applied rate as N%; 0, 100, 150, 200(basal dressing) and 100(basal dressing)+50(additional fertilizer) were divided by tillage methods; non-tillage, non-tillage+rice straw and rotary tillage method. Emission amounts of $NH_3$ gas highly decreased in the rotary tillage and the non-tillage+rice straw plot compared to non-tillage plot. The contents of soil organic matter and exchangeable cation were increased in the applied LPM plot. $NH_4-N$ and $NO_3-N$ contents in soil were the highest in the non-tillage+rice straw plot and followed by the rotary tillage and highly decreased along with the growth of plant. Run-off rate of mineral components were higher in order of the rotary tillage plot£æthe non-tillage plot£æthe non-tillage+rice straw plot and then leached to $SO_4$, $NO_3-N$, K plentifully. The yield of silage barley in dry weight was higher in order of the non-tillage+rice straw plot>the rotary tillage plot>the non-tillage plot. To estimate the feed value of silage barley, crude protein, acid detergent fiber(ADF) and neutral detergent fiber(NDF) contents were analyzed. Crude protein and ADF contents were the highest at rotary tillage N150% plot as 9.7 and 29.4%, respectively. NDF contents was the highest at non-tillage+rice straw N150% plot as 56.7%. In conclusion, we recommend not to incinerate rice straw and to apply LPM at non-tillage status in cultivating the silage barley. This may prevent water pollution and increase barley yields.

• Journal of Korean Home Economics Education Association
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• v.24 no.2
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• pp.29-49
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• 2012

The purpose of this study is to look at families as presented on the technology-home economics subject of middle school. To do this, I analyzed the 2007 revised curriculum of the technology-home economics subject, 'Changing Families,' in 11 technology-home economics textbooks (8th grade). The findings are as follows. First, family-related chapters are expanded compared with the previous curriculum in the 2007 revised curriculum. In addition, the new version emphasizes understanding and acceptance of change in families to improve the family life of adolescents. Second, in the 11 types of technology-home economics textbooks, the focusing was on the meaning of the family, the family structure, the function of the family, family roles and family values. There were also no major differences in the aspect of development. Third, in the technology-home economics textbooks, the family was defined as the 'basic group of society', 'a group composed by blood relationships, marriage and adoption', 'an affective group' and 'cohabiting group'. At the same time, there were many cases in which the description of the family was overly romanticized. Such a description of the family does not match the individual family experience of an adolescent. Fourth, all of textbooks dealt with the diversity of the family structure, such as single-parent families, remarriages families, and multi-cultural families. However, the structural characteristics and problems with these types of families are excessively emphasized, which can result in students having stereotypical images of specific family types. Fifth, the explanation of the function of the family was similar among textbooks. The importance of intergenerational cooperation and gender equality was also emphasized. However, such a concept is not considered as proper in a modern society. Thus, the description of a family based on the nuclear family should be sublated. In addition, the explanation of families overall should be developed in such a way that adolescents can interpret their own family experience rather than as an enlightening declaration of the family which disregards the dynamic relationships individual families actually experience.

• Journal of Korean Home Economics Education Association
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• v.21 no.4
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• pp.71-89
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• 2009

The purpose of this paper was to suggest effective management of clothing department in vocational high schools. Bibliographic research on ten vocational high schools' clothing departments was done. Also a survey was done to figure out what students and teachers think of clothing department education. The results were as follows. There are ten clothing departments in vocational high schools countrywide. 1493 students are enrolled in the department and they are taught by 51 teachers. Each school has two to seven laboratories. Professional subject time assignment of clothing department varies from 82 to 112 hours. Students chose clothing department in order to enter the university and their satisfaction on the department was "fair." Students' satisfaction level of professional education courses was "fair" and they felt difficulties both in theory and practice. Students answered that Embroidery/Knitting courses should be closed and Fashion Coordination be opened. Students were "fairly" satisfied with facilities for practice and felt job training was necessary. Most of them wanted to enter university after high school graduation. Teachers answered professional education curriculum was "fair." They found it necessary to improve the textbooks and felt both theory and practice difficult. They wanted Embroidery/Knitting courses to be closed and Fashion CAD course to be installed. From the teachers' view, students' prospect was better to enter university than to get a job. Teachers suffered from too much teaching-unrelated workload and wanted the number of teachers to be increased. Considering the above results, vocational high schools should concentrate their efforts on making students continue to study by extending the way to enter the same department of university as department of vocational high schools. In addition, they should develop various practice programs through field practice and educational-industrial relationship to help students get jobs. Both teachers and students think that the clothing department curriculum is difficult now. Therefore, the level of the curriculum should be adjusted. Finally, it was necessary to increase the number of teachers and to carry out teachers' training to raise quality in education.