• Journal of Intelligence and Information Systems
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• v.25 no.1
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• pp.63-83
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• 2019

Investors prefer to look for trading points based on the graph shown in the chart rather than complex analysis, such as corporate intrinsic value analysis and technical auxiliary index analysis. However, the pattern analysis technique is difficult and computerized less than the needs of users. In recent years, there have been many cases of studying stock price patterns using various machine learning techniques including neural networks in the field of artificial intelligence(AI). In particular, the development of IT technology has made it easier to analyze a huge number of chart data to find patterns that can predict stock prices. Although short-term forecasting power of prices has increased in terms of performance so far, long-term forecasting power is limited and is used in short-term trading rather than long-term investment. Other studies have focused on mechanically and accurately identifying patterns that were not recognized by past technology, but it can be vulnerable in practical areas because it is a separate matter whether the patterns found are suitable for trading. When they find a meaningful pattern, they find a point that matches the pattern. They then measure their performance after n days, assuming that they have bought at that point in time. Since this approach is to calculate virtual revenues, there can be many disparities with reality. The existing research method tries to find a pattern with stock price prediction power, but this study proposes to define the patterns first and to trade when the pattern with high success probability appears. The M & W wave pattern published by Merrill(1980) is simple because we can distinguish it by five turning points. Despite the report that some patterns have price predictability, there were no performance reports used in the actual market. The simplicity of a pattern consisting of five turning points has the advantage of reducing the cost of increasing pattern recognition accuracy. In this study, 16 patterns of up conversion and 16 patterns of down conversion are reclassified into ten groups so that they can be easily implemented by the system. Only one pattern with high success rate per group is selected for trading. Patterns that had a high probability of success in the past are likely to succeed in the future. So we trade when such a pattern occurs. It is a real situation because it is measured assuming that both the buy and sell have been executed. We tested three ways to calculate the turning point. The first method, the minimum change rate zig-zag method, removes price movements below a certain percentage and calculates the vertex. In the second method, high-low line zig-zag, the high price that meets the n-day high price line is calculated at the peak price, and the low price that meets the n-day low price line is calculated at the valley price. In the third method, the swing wave method, the high price in the center higher than n high prices on the left and right is calculated as the peak price. If the central low price is lower than the n low price on the left and right, it is calculated as valley price. The swing wave method was superior to the other methods in the test results. It is interpreted that the transaction after checking the completion of the pattern is more effective than the transaction in the unfinished state of the pattern. Genetic algorithms(GA) were the most suitable solution, although it was virtually impossible to find patterns with high success rates because the number of cases was too large in this simulation. We also performed the simulation using the Walk-forward Analysis(WFA) method, which tests the test section and the application section separately. So we were able to respond appropriately to market changes. In this study, we optimize the stock portfolio because there is a risk of over-optimized if we implement the variable optimality for each individual stock. Therefore, we selected the number of constituent stocks as 20 to increase the effect of diversified investment while avoiding optimization. We tested the KOSPI market by dividing it into six categories. In the results, the portfolio of small cap stock was the most successful and the high vol stock portfolio was the second best. This shows that patterns need to have some price volatility in order for patterns to be shaped, but volatility is not the best.

• The Korean Journal of Nuclear Medicine Technology
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• v.26 no.2
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• pp.43-47
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• 2022

Purpose Radioimmunoassay implement quality control by systematizing the internal quality control system for quality assurance of test results. This study aims to contribute to the quality assurance of radioimmunoassay results and to implement systematic quality control by measuring the average CV of internal quality control and external quality control by plenty of institutions for reference when setting the laboratory's own acceptable range. Materials and Methods We measured the average CV of internal quality control and the bounce rate of more than 10.0% for a total of 42 items from October 2020 to December 2021. According to the CV result, we classified and compared the upper group (5.0% or less), the middle group (5.0~10.0%) and the lower group (10.0% or more). The bounce rate of 10.0% or more was compared by classifying the item of five or more institutions into tumor markers, thyroid hormones and other hormones. The average CV was measured by the overall average and standard deviation of the external quality control results for 28 items from the first quarter to the fourth quarter of 2021. In addition, the average CV was measured by the overall average and standard deviation of the proficiency results between institutions for 13 items in the first half and the second half of 2021. The average CV of internal quality control and external quality control was compared by item so we compared and analyzed the items that implement well to quality control and the items that require attention to quality control. Results As a result of measuring the precision average of internal quality control for 42 items of six institutions, the top group (5.0% or less) are Ferritin, HGH, SHBG, and 25-OH-VitD, while the bottom group (≤10.0%) are cortisol, ATA, AMA, renin, and estradiol. When comparing more than 10.0% bounce rate of CV for tumor markers, CA-125 (6.7%), CA-19-9 (9.8%) implemented well, while SCC-Ag (24.3%), CA-15-3 (26.7%) were among the items that require attention to control. As a result of comparing the bounce rate of more than 10.0% of CV for thyroid hormones examination, free T4 (2.1%), T3 (9.3%) showed excellent performance and AMA (39.6%), ATA (51.6%) required attention to control. When comparing the bounce rate of 10.0% or more of CV for other hormones, IGF-1 (8.8%), FSH (9.1%), prolactin (9.2%) showed excellent performance, however estradiol (37.3%), testosterone (37.7%), cortisol (44.4%) required attention to control. As a result of measuring the average CV of the whole institutions participating at external quality control for 28 items, HGH and SCC-Ag were included in the top group (≤10.0%), however ATA, estradiol, TSI, and thyroglobulin included in bottom group (≥30.0%). Conclusion As a result of evaluating 42 items of six institutions, the average CV was 3.7~12.2% showing a 3.3 times difference between the upper group and the lower group. Cortisol, ATA, AMA, Renin and estradiol tests with high CV will require continuous improvement activities to improve precision. In addition, we measured and compared the overall average CV of the internal quality control, the external quality control and the proficiency between institutions participating of six institutions for 41 items excluding HBs-Ab. As a result, ATA, AMA, Renin and estradiol belong to the same subgroup so we require attention to control and consider setting a higher acceptable range. It is recommended to set and control the acceptable range standard of internal quality control CV in consideration of many things in the laboratory due to the different reagents and instruments, and the results vary depending on the test's proficiency and quality control materials. It is thought that the accuracy and reliability of radioimmunoassay results can be improved if systematic quality control is implemented based on the set acceptable range.

• Korean Journal of Breeding Science
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• v.51 no.3
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• pp.263-276
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• 2019

'Sinjinbaek' is a bacterial blight (BB)-resistant, mid-late maturing rice cultivar with high grain quality. To diversify the resistance genes and enhance the resistance of Korean rice cultivars against BB, 'Sinjinbaek' was developed from a cross between 'Iksan493' (cultivar name 'Jinbaek') and the F₁ cross between 'Hopum' and 'HR24670-9-2-1' ('HR24670'). 'Jinbaek' is a BB-resistant cultivar with two BB resistance genes, Xa3 and xa5. 'Hopum' is a high grain quality cultivar with the Xa3 resistance gene. 'HR24670' is a near-isogenic line that carries the Xa21 gene, a resistance gene inherited from a wild rice species O. longistaminata, in the genetic background of japonica elite rice line 'Suweon345'. 'Sinjinbaek' was selected through the pedigree method, yield trials, and local adaptability tests. Using bioassay for BB races and DNA markers for resistance genes, three resistance genes, Xa3, xa5, and Xa21, were pyramided in the 'Sinjinbaek' cultivar. 'Sinjinbaek' exhibited high-level and broad-spectrum resistance against BB, including the K3a race, the most virulent race in Korea. 'Sinjinbaek' is a mid-late maturing rice cultivar tolerant to lodging. It has multiple disease resistance against BB, rice blast, and stripe virus. The yield of 'Sinjinbaek' was similar to that of 'Nampyeong'. 'Sinjinbaek' showed excellent grain appearance, good taste of cooked rice, and enhanced milling performance, and we concluded that it could contribute to improving the quality of BB-resistant cultivars. 'Sinjinbaek' was successfully introgressed with the Xa21 gene without the linkage drag negatively affecting its agronomic characteristics. 'Sinjinbaek' improved the resistance of Korean rice cultivars against BB by introgression of a new resistance gene, Xa21, as well as by pyramiding three resistance genes, Xa3, xa5, and Xa21. 'Sinjinbaek' would be suitable for the cultivation in BB-prone areas since it has been used in breeding programs for enhancing plants' resistance to BB (Registration No. 7273).

• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.45-59
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• 1997

It has been known that there is a tracking phenomenon in the level of serum lipids. However, no study has been performed to examine the change and tracking of serum lipids in Korean adolescents. The purpose of this study is to examine the changes of serum lipids in Korean adolescents from 12 to 16 years of age, and to examine whether or not there is a tracking phenomenon in serum lipids level during the period. In 1992 serum lipids(total cholesterol(TC), triglyceride(TG), LDL cholesterol(LDL-C), HDL cholesterol(HDL-C)) were measured in 318 males, 365 females who were 12 years of age in Kangwha county, Korea. These participants have been followed up to 1996 and serum lipids level were examined in 1994 and 1996. Among the participants 162 males and 147 females completed all three examinations in fasting state. To examine the effect of eliminating adolescents with incomplete data, we compared serum lipids, blood pressure and anthropometric measures at baseline between adolescents with complete follow-up and adolescents who were withdrawn. To examine the change of serum lipids we compared mean values of serum lipids according to age in males and females. Repeated analysis of variance was used to test the change according to age. We used three methods to examine the existence of tracking. First, we analyzed the trends in serum lipids over 4-year period within quartile groups formed on the basis of the first-year serum lipids level to see whether or not the relative ranking of the mean serum lipids among the quartile groups remained in the same group for 4-year period. Second, we quantified the degree of tracking by calculating Spearman's rank correlation coefficient between every tests. Third, the persistence extreme quartile method was used. This method divides the population into quartile groups according to the initial level of blood lipids and then calculates the percent of the subjects who stayed in the same group at follow-up measurement. The decreases in levels were noted during 4 years for TC, LDL-C, primarily for boys. The level of HDL-C decreased between baseline and first follow-up for both sexes. Tracking, as measured by both correlation coefficients and persistence extreme quartiles, was evident for all of the lipids. The correlation coefficients of TC between baseline and 4 years later in boys and girls were 0.55 and 0.68, respectively. And the corresponding values for HDL-C were 0.58 and 0.69. More than 50% of adolescents who belonged to the highest quartile group in TC, HDL-C and LDL-C at the baseline were remained at the same group at the examination performed 2 years later for both sexes. The probabilities of remaining at the same group were more than 35% when examined 4 years later. The tracking phenomenon of TG was less evident compared with the other lipids. Percents of girls who stayed at the same group 2 years later and 4 years later were 42.9% and 25.7%, respectively. It was evident that serum lipid levels tracked in Korean adolescents. Researches with longer follow-up would be needed in the future to investigate the long-term change of lipids from adolescents to adults.

• Journal of Preventive Medicine and Public Health
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• v.31 no.1 s.60
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• pp.112-126
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• 1998

To investigate the effectiveness of the interventions in working environment and personal hygiene for the occupational exposure to the lead, the blood zinc protoporphyrin (ZPP) concentrations of 131 workers (100 exposed subjects and 31 controls) of a newly established battery factory were analyzed. They were measured in every 3 months up to 18 months. Ai. lead concentration (Pb-A) of the workplaces was also checked for 3 times in 6 months interval from August 1987. Environmental intervention included the local exhaust ventilation and vacuum cleaning of the floor. Intervention of the personal hygiene included the daily change of clothes, compulsory shower after work and hand washing before meal, prohibition of cigarette smoking and food consumption at the work site and wearing mask. Mean blood ZPP concentration of the controls was $16.45{\pm}4.83{\mu}g/d\ell$ at the preemployment examination and slightly increased to $17.77{\pm}5.59{\mu}g/d\ell$ after 6 months. Mean blood ZPP concentration of the exposed subjects who were employed before the factory was in operation (Group A) was $17.36{\pm}5.20{\mu}g/d\ell$ on employment and it was increased to $23.00{\pm}13.06{\mu}g/d\ell$ after 3 months. The blood ZPP concentration was increased to $27.25{\pm}6.40{\mu}g/d\ell$ on 6 months (p<0.01) after the employment which was 1 month after the initiation of intervention program. It did not increase thereafter and ranged between $25.48{\mu}g/d\ell$ and $26.61{\mu}g/d\ell$ in the subsequent 4 results. Mean blood ZPP concentration of the exposed subjects who were employed after the factory had been in operation but before the intervention program was initiated (Group B) was $14.34{\pm}6.10{\mu}g/d\ell$ on employment and it was increased to $28.97{\pm}7.14{\mu}g/d\ell$ (p<0.01) in 3 months later(1 month after the intervention). The values of subsequent 4 tests were maintained between $26.96{\mu}g/d\ell$and $27.96{\mu}g/d\ell$. Mean blood ZPP concentration of the exposed subjects who were employed after intervention program had been started (Group C) was$21.34{\pm}5.25{\mu}g/d\ell$ on employment and it was gradually increased to $23.37{\pm}3.86{\mu}g/d\ell$ (p<0.01) after 3 months, $23.93{\pm}3.64{\mu}g/d\ell$ after 6 months, $25.50{\pm}3.01{\mu}g/d\ell$ after 9 months, and $25.50{\pm}3.10{\mu}g/d\ell$ after 12 months. Workplaces were classified into 4 parts according to Pb-A. The Pb-A of part I, the highest areas, were $0.365mg/m^3$, and after the intervention the levels were decreased to $0.216mg/m^3$ and$0.208mg/m^3$ in follow-up test. The Pb-A of part II which was resulted in lowe. value than part I was decreased from $0.232mg/m^3$ to $0.148mg/m^3$, and $0.120mg/m^3$ after the intervention. The Pb-A of part III was tested after the intervention and resulted in $0.124mg/m^3$ in January 1988 and $0.181mg/m^3$ in August 1988. The Pb-A of part IV was also tested after the intervention and resulted in $0.110mg/m^3$ in August 1988. There was no consistent relationship between Pb-A and blood ZPP concentration. The blood ZPP concentration of the group A and B workers in the part of the highest Pb-A were lower than those of the workers in the parts of lower Pb-A. The blood ZPP concentration of the workers in the part of the lowest Pb-A increased more rapidly. The blood ZPP concentration of the group C workers was the highest in part III. These findings suggest that the intervention in personal hygiene is more effective than environmental intervention, and it should be carried out from the first day of employment and to both the exposed subjects, blue color workers and the controls, white color workers.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.1-34
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• 1974

These experiments pertain to various factors influencing the quantitative characters of cocoon crops in summer and early autumn seasons. Initially, in order to establish the possible ways of the silkworm rearing more than three times a year in Korea, the author attempted to get further information about the various factors affecting the cocoon crop in every silkworm rearing season. The trials were conducted eleven times a year at four places for three years. The field trial was conducted with 19 typical sericultural farmers who had been surveyed. At the same time the author statistically analyzed the various factors in close relation to tile cocoon crop in autumn season. The effect of guidance on 40 sericultural farmers was analyzed, comparing higher level farmers with lower level farmers ; and the author surveyed 758 non-guided farmers near the guided farmers during both spring and autumn seasons. In addition, another trial on the seasonal change of leaf quality was attempted with artificial diets prepared with leaves grown in each season. It was found that related factors to cocoon crops in summer and early autumn seasons appeared to be leaf quality, and temperature for young and grown larvae. A 2$^4$ factorial experiment was designed in summer season, and another design with one more level of varied temperature or hard leaf added to a 24 factorial experiment was conducted in early autumn. The experimental results can be summarized： 1. Study on the cocoon crops in the different rearing seasons 1) It was shown that earlier brushing of silkworm generally produced the most abundant cocoon crop in spring season, and earlier or later than the conventional brushing season, especially earlier brushing was unfavorable for the abundant cocoon crop in autumn season. 2) The cocoon crop was affected by the rearing season, and decreases in order of sire with spring, autumn, late autumn, summer and early autumn seasons. 3) It was Proved that ordinary rearing and branch rearing were possibles 4 times a year ; in the 1st, 3rd, 8th, and 10th brushing season. But the 11th brushing season was more favorable for the most abundant cocoon crop of branch rearing, instead of the 10th brushing season with ordinary rearing. 2. Study on the main factors affecting the cocoon crop in autumn season 1) Accumulated pathogens were a lethal factor leading to a bad cocoon crop through neglect of disinfection of rearing room and instruments. 2) Additional factors leading to a poor cocoon crop were unfavorable for rearing temperature and humidity, dense population, poor choice of moderately ripened leaf, and poor feeding techniques. However, it seemed that there was no relationship between the cocoon crop and management of farm. 3) The percentage of cocoon shell seemed to be mostly affected by leaf quality, and secondarily affected by the accumulation of pathogens. 3. Study on the effect of guidance on rearing techniques 1) The guided farms produced an average yearly yield of 29.0kg of cocoons, which varied from 32.3kg to 25.817g of cocoon yield per box in spring versus autumn, respectively. Those figures indicated an annual average increase of 26% of cocoon yield over yields of non-guided farmers. An increase of 20% of cocoon yield in spring and 35% of cocoon yield in autumn were responsible. 2) On guided farms 77.1 and 83.7% of total cocoon yields in the spring and autumn seasons, respectively, exceeded 3rd grade. This amounted to increases of 14.1 and 11.3% in cocoon yield and quality over those of non-guided farms. 3) The average annual cocoon yield on guided farms was 28.9kg per box, based on a range of 31.2kg to 26.9kg per box in spring and autumn seasons, respectively. This represented an 8% increase in cocoon yield on farms one year after guidance, as opposed to non-guided farms. This yield increase was due to 3 and 16% cocoon yield increases in spring and autumn crops. 4) Guidance had no effect on higher level farms, but was responsible for 19% of the increases in production on lower level farms. 4. Study on the seasonal change of leaf quality 1) In tests with grown larvae, leaves of tile spring crop incorporated in artificial diets produced the best cocoon crop; followed by leaves of the late autumn, summer, autumn, and early autumn crops. 2) The cocoon crop for young larvae as well as for grown larvae varied with the season of leaf used. 5. Study on factors affecting the cocoon crops in summer and early autumn A. Early autumn season 1) Survival rate and cocoon yield were significantly decreased at high rearing temperatures for young larvae 2) Survival rate, cocoon yield, and cocoon quality were adversely affected by high rearing temperatures for grown larvae. Therefore increases of cocoon quantity and improvement of cocoon quality are dependent on maintaining optimum temperatures. 3) Decreases in individual cocoon weight and longer larval periods resulted with feeding of soft leaf and hard leaf to young larvae, but the survival rate, cocoon yield and weight of cocoon shell were not influenced. 4) Cocoon yield and cocoon quality were influenced by feeding of hard leaf to grown larvae, but survival rate was not influenced by the feeding of soft leaf and hard leaf. 5) When grown larvae were inevitably raised at varied temperatures, application of varied temperature in the raising of both young and grown larvae was desirable. Further research concerning this matter must be considered. B. Summer season 1) Cocoon yield and single cocoon weight were decreased at high temperatures for young larvae and survival rate was also affected. 2) Cocoon yield, survival rate. and cocoon quality were considerably decreased at high rearing temperatures for grown larval stages.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.95-100
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• 2013

Purpose: Since 2008, hepatitis A patients was rapidly increasing. So, Most of the health checkup examinees were interested in whether hepatitis A antibody was a lot. thereby The number of tests was increasing. In recent years, Antibody test results in the range of cut-off values were increased. According to the cause analysis, most examinees had a hepatitis A vaccine. This study was conducted to classify hepatitis A antibody as natural antibody and antibody after vaccination and compared the titer for seroconversion rate based on cut-off values. Materials and Methods: For a month in August 2012, First, We surveyed 185 health examinees and classified 119 health examinees who had acquired natural antibody. Second, for employees who were inoculated against hepatitis at our hospital, We classified into 53 primary inoculators and 59 secondary inculators. when the standard of cut-off value was 1, The seroconversion rate was compared the titer divided by 0.90-1.10 (${\pm}$), 0.60-0,89 (1+), 0.30-0.59 (2+), 0.01-0.29 (3+) and we compared the titer for seroconversion rate by each manufacturer after vaccination. Results: When the standard of cut-off value was 1, the titer of 119 health examinees who had acquired natural antibody was 0.90-1.10 (${\pm}$): 0%, 0.60-0.89 (1+): 0%, 0.30-0.59 (2+): 4.2%, 0.01-0.29 (3+): 96% and the titer of <0.60 ($${\geq_-}2+$$) was 100%. The titer of 53 primary inoculators was 0.90-1.10 (${\pm}:59.1%$), 0.60-0.89 (1+): 18.1%, 0.30-0.59 (2+): 18.1%, 0.01-0.29 (3+): 4.6% and the seroconversion rate was 45.3%. The titer of $${\geq_-}0.60$$ ($${\leq_-}1+$$) was 77.3%. The titer of 59 secondary inoculators was 0.90-1.10 (${\pm}:1.9%$), 0.60-0.89 (1+): 15.4%, 0.30-0.59 (2+): 36.54%, 0.01-0.29 (3+): 46.2% and the seroconversion rate was 88.1%. The titer of <0.60 ($${\geq_-}2+$$) was 82.7%. When we compared the titer for seroconversion rate by each manufacturer after vaccination, the seroconversion rate of 53 primary inoculators was BNIBT: 20.8% (${\pm}:24.5%$), GB: 15.7% (${\pm}:7.8%$), RIAKEY: 94.3% (${\pm}:3.8%$), ROCHE: 83% (${\pm}:0%$), ABBOTT: 73.1% (${\pm}:5.8%$) and the seroconversion rate of 59 secondary inoculators was BNIBT : 86.4% (${\pm}:1.7%$), GB: 88.5% (${\pm}:1.9%$), RIAKEY: 100% (${\pm}:0%$), ROCHE: 98.3% (${\pm}:0%$), ABBOTT: 98.2% (${\pm}:0%$). Conclusion: The study show that the titer of natural immune antibodies is higher than the titer of vaccination and the titer of secondary inoculation is mainly higher than the titer of primary inoculation. Consequently, if we know the titer of hepatitis A antibodies, it will help to give resullt reports. And then, when we compared the titer and the seroconversion rate by each manufacturer, There was a very distinct difference. As the test subjects inoculate against hepatitis A (HAV), it is considered BNIBT, GB will occur false negative rate and RIAKEY, ROCHE, ABOTT will occur false positive rate.

• Journal of Animal Environmental Science
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• v.10 no.1
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• pp.11-22
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• 2004

This work was carried out to measure volatile fatty acids emissions from different manure (poultry, swine, cattle) incubated at $10^{\circ}C$, $25^{\circ}C$, and $37^{\circ}C$ for 6 days under anaerobic condition. Following are summary of these tests results. 1. Amounts of Acetic acid generated were 1,128.05mg/kg, 628.21mg/kg and 592.50mg/kg for swine, poultry, and cattle manure, respectively, during the period of incubation. In the case of swine and cattle manure, 83.87%(946.10mg/kg) and 57.49%(340.63mg/kg) from all the temperature treatments were produced in the $25^{\circ}C$, respectively. 83.57% in swine and 78.79% in cattle manure were intensively emerged from 3 day, 4 day and 5 day of the $25^{\circ}C$ treatment. In the case of poultry manure, 45.36%(284.93mg/kg) and 45.36%(284.93mg/kg) in the $25^{\circ}C$ and in the $37^{\circ}C$, respectively, were produced. Accordingly, acetic acid generated from poultry manure was characteristic of being mainly produced in more than $25^{\circ}C$. 2. Amounts of propionic acid generated were 238.56mg/kg, 162.14mg/kg and 155.49mg/kg for swine, poultry, and cattle manure, respectively, during the period of incubation. In the case of swine manure, 78.52%(187.32mg/kg) of propionate emitted from all the temperature treatments was produced in the $25^{\circ}C$ and 79.1% of them was intensively emerged from 3day, 4day and 5day of the $25^{\circ}C$ treatment. In the case of poultry manure, 35.12%(56.95mg/kg) and 45.89%(74.40mg/kg) of the propionate amounts were produced in the $25^{\circ}C$ and in the $37^{\circ}C$, respectively. In the case of cattle manure, 28.21% (43.86mg/kg) and 49.30% (76.66mg/kg) of the propionate amounts were produced in the $10^{\circ}C$ and in the $25^{\circ}C$, respectively. Accordingly, propionate evolved from poultry manure was characteristic of being mainly produced in more than $25^{\circ}C$ and from cattle manure, in less than $25^{\circ}C$, respectively. 3. Amount of butyric acid generated were 1,463.87mg/kg, 96.72mg/kg and 129.18mg/kg for swine, poultry, and cattle manure, respectively, during the period of incubation. The time intensively emerged from the period of incubation was differently generated from the incubation temperature and animal feces. 4. Amounts of iso-valeric acid generated were 6,885.99mg/kg, 399.28mg/kg and 307.47mg/kg for swine, cattle and poultry manure, respectively, during the period of incubation. In the case of swine and cattle manure, 28.22%(1,943.52mg/kg) and 48.56%(193.90mg/kg) in the $25^{\circ}C$, 68.76%(4,734.90mg/kg) and 46.93%(187.40mg/kg) in the $37^{\circ}C$, respectively, were occupied. Accordingly, iso-valeric acid evolved from swine and cattle manure was characteristic of being mainly produced in more than $25^{\circ}C$. In the case of poultry manure, 59.89%(184.13mg/kg) of iso-valeric acid generated from all the temperature treatments was produced in the $37^{\circ}C$ and 100% of them was intensively emerged from 2 day and 3 day of the $37^{\circ}C$ treatment.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.3
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• pp.196-205
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• 2004

As far as an opening device of fishing gears is concerned, applications of a kite are under development around the world. The typical examples are found in the opening device of the stow net on anchor and the buoyancy material of the trawl. While the stow net on anchor has proved its capability for the past 20 years, the trawl has not been wildly used since it has been first introduced for the commercial use only without sufficient studies and thus has revealed many drawbacks. Therefore, the fundamental hydrodynamics of the kite itself need to ne studied further. Models of plate and canvas kite were deployed in the circulating water tank for the mechanical test. For this situation lift and drag tests were performed considering a change in the shape of objects, which resulted in a different aspect ratio of rectangle and trapezoid. The results obtained from the above approaches are summarized as follows, where aspect ratio, attack angle, lift coefficient and maximum lift coefficient are denoted as A, B, $C_L$ and $C_{Lmax}$ respectively : 1. Given the rectangular plate, $C_{Lmax}$ was produced as 1.46${\sim}$1.54 with A${\leq}$1 and 40$^{\circ}$${\leq}$B${\leq}$42$^{\circ}$. And when A${\geq}$1.5 and 20$^{\circ}$${\leq}$B${\leq}$22$^{\circ}$, $C_{Lmax}$ was 10.7${\sim}$1.11. Given the rectangular canvas, $C_{Lmax}$ was 1.75${\sim}$1.91 with A${\leq}$1 and 32$^{\circ}$${\leq}$B${\leq}$40$^{\circ}$. And when A${\geq}$1.5 and 18$^{\circ}$${\leq}$B${\leq}$22$^{\circ}$, $C_{Lmax}$ was 1.24${\sim}$1.40. Given the trapezoid kite, $C_{Lmax}$ was produced as 1.65${\sim}$1.89 with A${\leq}$1.5 and 34$^{\circ}$${\leq}$B${\leq}$44$^{\circ}$. And when A=2 and B=14${\sim}$48, $C_L$ was around 1. Given the inverted trapezoid kite, $C_{Lmax}$ was 1.57${\sim}$1.74 with A${\leq}$1.5 and 24$^{\circ}$${\leq}$B${\leq}$36$^{\circ}$. And when A=2, $C_{Lmax}$ was 1.21 with B=18$^{\circ}$. 2. For a model with A=1/2, an increase in B caused an increase in $C_L$ until $C_L$ has reached the maximum. Then there was a tendency of a gradual decrease in the value of $C_L$ and in particular, the rectangular kite showed a more rapid decrease. For a model with A=2/3, the tendency of $C_L$ was similar to the case of a model with A=1/2 but the tendency was a more rapid decrease than those of the previous models. For a model with A=1, and increase in B caused an increase in $C_L$ until $C_L$ has reached the maximum. Soon after the tendency of $C_L$ decreased dramatically. For a model with A=1.5, the tendency of $C_L$ as a function of B was various. For a model with A=2, the tendency of $C_L$ as a function of B was almost the same in the rectangular and trapezoid model. There was no considerable change in the models with 20$^{\circ}$${\leq}$B${\leq}$50$^{\circ}$. 3. The tendency of kite model's $C_L$ in accordance with increase of B was increased rapidly than plate models until $C_L$ has reached the maximum. Then $C_L$ in the kite model was decreased dramatically but in the plate model was decreased gradually. The value of $C_{Lmax}$ in the kite model was higher than that of the plate model, and the kite model's attack angel at $C_{Lmax}$ was smaller than the plate model's. 4. In the relationship between aspect ratio and lift force, the attack angle which had the maximum lift coefficient was large at the small aspect ratio models, At the large aspect ratio models, the attack angle was small. 5. There was camber vertex in the position in which the fluid pressure was generated, and the rectangular & trapezoid canvas had larger value of camber vertex when the aspect ratio was high, while the inverted trapezoid canvas was versa. 6. All canvas kite had larger camber ratio when the aspect ratio was high, and the rectangular & trapezoid canvas had larger one when the attack angle was high.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.9 no.1
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• pp.1-18
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• 1973

For regulating the depth of midwater trawl nets towed at the optimum constant speed, the changes in the shape of warps caused by adding a weight on an arbitrary point of the warp of catenary shape is studied. The shape of a warp may be approximated by a catenary. The resultant inferences under this assumption were experimented. Accordingly feasibilities for the application of the result of this study to the midwater trawl nets were also discussed. A series of experiments for basic midwater trawl gear models in water tank and a couple of experiments of a commercial scale gears at sea which involve the properly designed depth control devices having a variable attitude horizontal wing were carried out. The results are summarized as follows: 1. According to the dimension analysis the depth y of a midwater trawl net is introduced by $$y=kLf(\frac{W_r}{R_r},\;\frac{W_o}{R_o},\;\frac{W_n}{R_n})$$) where k is a constant, L the warp length, f the function, and $W_r,\;W_o$ and $W_n$ the apparent weights of warp, otter board and the net, respectively, 2. When a boat is towing a body of apparent weight $W_n$ and its drag $D_n$ by means of a warp whose length L and apparent weight $W_r$ per unit length, the depth y of the body is given by the following equation, provided that the shape of a warp is a catenary and drag of the warp is neglected in comparison with the drag of the body: $$y=\frac{1}{W_r}\{\sqrt{{D_n^2}+{(W_n+W_rL)^2}}-\sqrt{{D_n^2+W_n}^2\}$$ 3. The changes ${\Delta}y$ of the depth of the midwater trawl net caused by changing the warp length or adding a weight ${\Delta}W_n$_n to the net, are given by the following equations: $${\Delta}y{\approx}\frac{W_n+W_{r}L}{\sqrt{D_n^2+(W_n+W_{r}L)^2}}{\Delta}L$$ $${\Delta}y{\approx}\frac{1}{W_r}\{\frac{W_n+W_rL}{\sqrt{D_n^2+(W_n+W_{r}L)^2}}-{\frac{W_n}{\sqrt{D_n^2+W_n^2}}\}{\Delta}W_n$$ 4. A change ${\Delta}y$ of the depth of the midwater trawl net by adding a weight $W_s$ to an arbitrary point of the warp takes an equation of the form $${\Delta}y=\frac{1}{W_r}\{(T_{ur}'-T_{ur})-T_u'-T_u)\}$$ Where $$T_{ur}^l=\sqrt{T_u^2+(W_s+W_{r}L)^2+2T_u(W_s+W_{r}L)sin{\theta}_u$$ $$T_{ur}=\sqrt{T_u^2+(W_{r}L)^2+2T_uW_{r}L\;sin{\theta}_u$$ $$T_{u}^l=\sqrt{T_u^2+W_s^2+2T_uW_{s}\;sin{\theta}_u$$ and $T_u$ represents the tension at the point on the warp, ${\theta}_u$ the angle between the direction of $T_u$ and horizontal axis, $T_u^2$ the tension at that point when a weights $W_s$ adds to the point where $T_u$ is acted on. 5. If otter boards were constructed lighter and adequate weights were added at their bottom to stabilize them, even they were the same shapes as those of bottom trawls, they were definitely applicable to the midwater trawl gears as the result of the experiments. 6. As the results of water tank tests the relationship between net height of H cm velocity of v m/sec, and that between hydrodynamic resistance of R kg and the velocity of a model net as shown in figure 6 are respectively given by $$H=8+\frac{10}{0.4+v}$$ $$R=3+9v^2$$ 7. It was found that the cross-wing type depth control devices were more stable in operation than that of the H-wing type as the results of the experiments at sea. 8. The hydrodynamic resistance of the net gear in midwater trawling is so large, and regarded as nearly the drag, that sweeping depth of the gear was very stable in spite of types of the depth control devices. 9. An area of the horizontal wing of the H-wing type depth control device was $1.2{\times}2.4m^2$. A midwater trawl net of 2 ton hydrodynamic resistance was connected to the devices and towed with the velocity of 2.3 kts. Under these conditions the depth change of about 20m of the trawl net was obtained by controlling an angle or attack of $30^{\circ}$.