• Korean Journal of Remote Sensing
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• v.25 no.4
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• pp.311-320
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• 2009

This study was carried out to estimate forest biomass and to produce forest biomass thematic map for Muju county by combining field data from the 5$^{th}$ National Forest Inventory (2006-2007) and satellite data. For estimating forest biomass, two methods were examined using a Landsat TM-5(taken on April 28th, 2005) and field data: multi-variant regression modeling and t-Nearest Neighbor (k-NN) technique. Estimates of forest biomass by the two methods were compared by a cross-validation technique. The results showed that the two methods provide comparatively accurate estimation with similar RMSE (63.75$\sim$67.26ton/ha) and mean bias ($\pm$1ton/ha). However, it is concluded that the k-NN method for estimating forest biomass is superior in terms of estimation efficiency to the regression model. The total forest biomass of the study site is estimated 8.4 million ton, or 149 ton/ha by the k-NN technique.

• Journal of Animal Science and Technology
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• v.62 no.6
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• pp.824-839
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• 2020

The current study was aimed to examine the effect of partial or complete replacement of fishmeal (FM) with fermented soybean meal (FSBM) on growth performance, fecal composition, and meat quality in broiler chickens. A total number of 240 one-day-old broiler chicks were randomly allotted into four dietary treatments with six replications and ten birds per one pen. Dietary treatments were followed as; 1) Diet incorporated with 4% FM without FSBM (Control), 2) Diet incorporated with 3% FM and 2% FSBM (FSBM2), 3) Diet incorporated with 2% FM and 3% FSBM (FSBM3) and 4) Diet incorporated with 4% FSBM without FM (FSBM4). Body weight and feed intake were recorded weekly for 35 days of the experimental period. Moreover, fecal samples were collected to evaluate moisture, ash, nitrogen, calcium and phosphorus content on day 21 post-hatch. On day 35, two birds were sacrificed from each pen to measure meat quality parameters and visceral organ weights. Results revealed that, no dietary treatment effect (p > 0.05) was observed either in both body weight or average daily gain of broilers within the entire experimental period while broilers fed FSBM2 increased (p < 0.05) average daily feed intake by 10.07% whereas FSBM4 improved (p < 0.05) feed efficiency ratio by 8.45% compared to birds fed other dietary treatments on day 7 post-hatch. Besides, birds fed FSBM3 obtained the improved (p < 0.05) feed conversion ratio over the birds fed control diet by 7.51% from hatch to day 35 post-hatch (1.60 vs. 1.73). Nevertheless, no difference (p > 0.05) was detected on visceral organ weight, proximate composition and physicochemical characteristics of meat while broilers offered FSBM4 obtained the lowest (p < 0.05) calcium and phosphorous in faces (2.27% and 1.21% respectively) over those offered control feed and other FSBM treatments. In conclusion, FSBM would be a better replacement for ousting FM partially or completely in broiler diet as it did not impair the growth performance and meat quality while reducing the calcium and phosphorous excretion in broilers for 35 days post-hatch.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.831-839
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• 2023

Tylosin is a potent veterinary macrolide antibiotic produced by the fermentation of Streptomyces fradiae; however, it is necessary to modify S. fradiae strains to improve tylosin production. In this study, we established a high-throughput, 24-well plate screening method for identifying S. fradiae strains that produce increased yields of tylosin. Additionally, we constructed mutant libraries of S. fradiae via ultraviolet (UV) irradiation and/or sodium nitrite mutagenesis. A primary screening of the libraries in 24-well plates and UV spectrophotometry identified S. fradiae mutants producing increased yields of tylosin. Mutants with tylosin yield 10% higher than the wild-type strain were inoculated into shake flasks, and the tylosin concentrations produced were determined by high-performance liquid chromatography (HPLC). Joint (UV irradiation and sodium nitrite) mutagenesis resulted in higher yields of mutants with enhanced tylosin production. Finally, 10 mutants showing higher tylosin yield were re-screened in shake flasks. The yield of tylosin A by strains UN-C183 (6767.64 ± 82.43 ㎍/ml) and UN-C137 (6889.72 ± 70.25 ㎍/ml) was significantly higher than that of the wild-type strain (6617.99 ± 22.67 ㎍/ml). These mutant strains will form the basis for further strain breeding in tylosin production.

• Korean Journal of Soil Science and Fertilizer
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• v.2 no.1
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• pp.53-68
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• 1969

The nutriophysiological response of rice plant to root environment was investigated with eye observation of root development and rhizosphere in situation. The results may be summarized as follows: 1) The quick decomposition of organic matter, added in low yield soil, caused that the origainal organic matter content was reached very quickly, in spite of it low value. In high yield soil the reverse was seen. 2) In low yield soil root development, root activity and T/R value were very low, whereas addition of organic matter lowered them still wore. This might be contributed to gas bubbles around the root by the decomposition of organic matter. 3) Varietal difference in the response to root environment was clear. Suwon 82 was more susceptible to growth-inhibitine conditions on low-yield soil than Norin 25. 4) Potassium uptake was mostly hindered by organic matter, while some factors in soil hindered mostly posphorus uptake. When the organic matter was added to such soil, the effect of them resulted in multiple interaction. 5) The root activity showed a correlation coeffieient of 0.839, 0.834 and 0.948 at 1% level with the number of root, yield of aerial part and root yield, respectively. At 5% level the root-activity showed correlation-coefficient of 0.751, 0.670 and 0.769 with the uptake of the aerial part of respectively. N, P and K and a correlation-coefficient of 0.729, 0.742 and 0.815 with the uptake of the root of respectively N.P. and K. So especially for K-uptake a high correlation with the root-activity was found. 6) The nitrogen content of the roots in low-yield soil was higher than in high-yield soil, while the content in the upper part showed the reverse. It may suggest ammonium toxicity in the root. In low-yield soil Potassium and Phosphorus content was low in both the root and aerial part, and in the latter particularly in the culm and leaf sheath. 7) The content of reducing sugar, non-recuding sugar, starh and eugar, total carbohydrates in the aerial part of plants in low yield soil was higher than in high yield soil. The content of them, especially of reducing sugar in the roots was lower. It may be caused by abnormal metabolic consumption of sugar in the root. 8) Sulfur content was very high in the aerial part, especially in leaf blade of plants on low yield soil and $P_2O_5/S$ value of the leaf blade was one fifth of that in high yield soil. It suggests a possible toxic effect of sulfate ion on photophosphorization. 9) The high value of $Fe/P_2O_5$ of the aerial part of plants in low yield soil suggests the possible formation of solid $Fe/PO_4$ as a mechanical hindrance for the translocation of nutrients. 10) Translocation of nutrients in the plant was very poor and most nutrients were accumulated in the root in low yield soil. That might contributed to the lack of energy sources and mechanical hindrance. 11) The amount of roots in high yield soil, was greater than that in low yield soil. The in high-yield soil was deep, distribution of the roots whereas in the low-yield soil the root-distribution was mainly in the top-layer. Without application of Nitrogen fertilizer the roots were mainly distributed in the upper 7cm. of topsoil. With 120 kg N/ha. root were more concentrated in the layer between 7cm. and 14cm. depth. The amount of roots increased with the amount of fertilizer applied.

• The korean journal of orthodontics
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• v.27 no.5 s.64
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• pp.839-852
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• 1997

It has been submitted that different ion solutions containing sulfate induce crystal growth and might substitute conventional acid etching for pretreatment of enamel in orthodontic bonding(${\AA}rtun$ et al., Am. J. Orthod. 85, 333, 1984). This investigation was designed to evaluate the relevance of crystal growth on the enamel surface as an alternative to conventional acid etching in direct bonding of orthodontic brackets. Annexing Li2SO4, MgSO4, K2SO4 respectively in the solution with $25\%$ polyacrylic md 0.3M sulfuric acids were employed to enhance the crystal growth. Human bicuspids were treated with various parameters as combinations of crystal growth and glass ionomer cement, crystal growth and orthodontic resin, acid etching and orthodontic resin for an investigative purpose. Crystal growth solution containing MgSO4 showed the highest shear bond strength(15.6MPa) within the groups of bonding brackets with glass ionomer cement(p<0.01). Bonding with glass ionomer cement on the surface of crystal growth demonstrated higher shear bond strength than with orthodontic resin(p<0.001). Bonding with glass ionomer cement on the surface treated with crystal growth solution containing MgSO4 or K2SO4 was not different shear bond strength statistically from bonding with orthodontic resin on the acid-etched surface. It suggests that bonding brackets with glass ionomer cement on the surface treated with crystal growth solution containing MgSO4 or K2SO4 is a potential alternative to bonding with resin on the acid etched sufrace.

• Journal of the Korean Society of International Agriculture
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• v.30 no.4
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• pp.313-319
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• 2018

The purpose of this study was to provide the basis for the vegetable seedlings export research and policy establishment by analyzing vegetable seedlings export status from the agricultural quarantine statistics in Korea and the changes of temperature and relative humidity during the vegetable seedlings shipping export transportation to Japan. From 2007 to 2016, various vegetable seedlings such as cabbage, tomatoes, cucumber, onion and etc., have been exported to more than 20 countries around the world. The main exporting country of vegetable seedlings for commercial purposes is Japan, and the major exported seedlings to Japan in 2016 were fruit vegetable grafted seedlings such as eggplant, tomato, cucumber, watermelon and pepper. Total export amount of the fruit vegetable seedlings to Japan in 2016 were 2,575,446 seedlings and it is approximately 0.7 to 1.6 million dollars. The grafted seedlings exported to Japan were consumed for urban agriculture and farm use. Shipping transportation took about 24 hours in the process of receiving the package ${\rightarrow}$ shipment ${\rightarrow}$ quarantine (Busan port) ${\rightarrow}$ Quarantine (Japan Shimonoseki Port). The growing demand for vegetable seedlings due to the development of urban agriculture in Japan and the growing interest and demand for vegetable grafting seedlings in neighboring countries such as Russia will be an opportunity to expand the export size of Korean vegetable grafting seedlings. In order to expand the export of vegetable seedlings in Korea, it is necessary to ensure further active government policy and research on the production of export seedlings, seedlings storage and transportation technology and analysis of exporting countries' market information.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.382-390
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• 2015

This work was conducted to investigate the performance and meat characteristics of commercial Korean native duck (KND). A total of 180 1-d-old ducklings of 2-way crossbreds from A and B lines (from National Institute of Animal Science) were used in this work and divided into 4 groups (3 replicates/group, 15 birds/replicate). The four groups were 4 crossbreds as AA (A line [♀]${\times}$A line [♂]), AB (A line [♀]${\times}$B line [♂]), BB (Pure line B strains) and BA (B strains [♀]${\times}$A strain [♂]). Ducks were fed diets based on corn-soybean meal for 0 to 3 wk (22.4% crude protein [CP], 2,945 kcal/kg metabolizable energy [ME]) and 3 to 8 wk (18.4% CP, 3,047 kcal/kg ME). As a result of this study, average body weight of 4 crossbreds were 625, 1,617, 2,466, and 2,836 g at 2, 4, 6, and 8 weeks, respectively, and significantly increased over the period of time (p<0.05). Body weight of BB group was greater than other crossbreds at the age of 6 weeks (p<0.05). There was a significant difference in weekly body weight gains (p<0.05), which were 573, 991, 850, and 371 g at 2, 4, 6, and 8 weeks old, respectively. Uniformity of 4 crossbreds was 84.9%, 80.5%, and 72.5% at 6, 7, and 8 weeks, respectively, and there was no difference among crossbreds. Body weight gain of BB crossbred was highest among crossbreds (p<0.05). Weekly feed intake significantly increased with weeks as 669, 1,839, 2,812, and 3,381 g at 2, 4, 6, and 8 weeks respectively (p<0.05). Feed intakes of AA and BB crossbreds were higher at 2 to 4 weeks old than others and that of BB crossbred was highest at 4 to 6 weeks old (p<0.05). Weekly feed conversion ratios were 1.17, 1.86, 3.32, and 9.37 at 0 to 2, 2 to 4, 4 to 6, and 6 to 8 weeks old, respectively, and it increased with age (p<0.05). There was no significant difference in feed conversion ratio among crossbreds. Carcass yields of 4 crossbreds were 73.6%, 71.6%, 73.5%, and 71.7%, respectively, so there was no significant difference among crossbreds. There was no difference in wing, neck, breast and leg ratios among crossbreds. However, back ratios of 4 crossbreds were 17.6%, 18.0%, 15.8%, and 17.6%, respectively, and back ratio of BB was the highest among crossbreds. Finally, these results may provide the basic data on the production, carcass quality, fatty acid and amino acid composition of commercial KND with 2-way crossbreeding.

• Journal of Preventive Medicine and Public Health
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• v.30 no.4 s.59
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• pp.830-839
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• 1997

Painting is risky work to occupational skin disease. This research was carried out to investigate the prevalence of occupational skin diseases in painting department of a shipyard company in June 1996. Dermatological examination, self-administered questionnaire survey were conducted. Exposed group(n=379) was selected randomly in painting department and control of group(n=151) was selected in those who had not exposed to paints or solvents. The prevalence of contact dermatitis(11.9%) is significantly elevated compared with control of group(2.6%), and odds ratio(OR) is 4.95 (95% confidence interval[CI]: 1.75-14.02). The prevalence of Tinea pedis, the most common skin disease, in exposure group is 48.0%, and its odds ratio(OR) is significantly elevated compared with control group (OR:3.18, 95% CI: 2.06-4.90). Pompholyx is also significantly elevated in prevalence(11.9%) and OR(OR:6.64, 95% CI:2.03-21.69). There were no difference in the prevalence of contact dermatitis, Tinea pedis, and pompholyx by use of personal protective equipments(PPE), job categories, and duration of employment in painting department. In exposure group, 71.1% suffer from contact dermatitis improved in vacation or holiday and 68.9% of them had lesion on exposed area, it suggest that contact dermatitis in exposed group is related to their work. In conclusion, workers in painting department have high risks of contact dermatitis, Tinea pedis, and pompholyx. A health policy should be provided to prevent skin disease among painting department.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.138-149
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• 2000

Purpose : It was studied that the relationship between radiation dose, dose rate and the frequency of chromosomal aberrations in peripheral lymphocytes. Methods and Materials : Peripheral lymphocytes were irradiated in vitro with 6 MeV X-ray at dose ranges from 50 cGy to 800 cGy. The variations of the frequency of chromosomal aberrations were observed according to different radiation dose rate from 20 cGy/min to 400 cGy/min at constant total dose of 400 cGy which it was considered as factor to correct biological radiation dose measurement. Results : The yields of lymphocytes with chromosomal aberrations (dicentric chromosome, ring chromosome, acentric fragment pairs) are 0% at 50 cGy, 9% at 100 cGy, 20% at 200 cGy, 27% at 300 cGy, 55% at 400 cGy, 88% at 600 cGy, and 100% at 800 cGy. The value of Ydr is 0.000 at 50 cGy, 0.093 at 100 cGy, 0.200 at 200 cGy, 0.354 at 300 cGy, 0.612 at 400 cGy, 2.040 at 600 cGy, and 2.846 at 800 cGy. The relationship between radiation (D) and the frequency of dicentrlc chromosomes and ring Chromosomes (Ydr) can be expressed as Ydr=0.188${\times}$10$^{-2}$ D/Gy+0.422${\times}$10$^{-4}$/Gy$^{2}$${\times}$D$^{2}$ The Value of Qdr is 0.000 at 50 cGy, 1.000 at 100 cGy, 1.000 at 200 cGy, 1.333 at 300 cGy, 1.118 at 400 cGy, 2.318 at 600 cGy, and 2.846 at 800 cGy. When 400 cGy is irradiated with different dose rate each of 20, 40, 60, 80, 100, 160, 240, 320, and 400 cGy/min, Ydr is each of 0.982, 0.837, 0.860, 0.732, 0.763, 0.966, 0.909, 1.006, and 0.806, and Qdr is each of 1.839, 1.555, 1.654, 1.333, 1.381, 1.750, 1.6000, 1.710, and 1.318. Conclusion : There are not the significant variations of Ydr and Qdr values according to different dose rate. And so radiation damage is influenced by total exposed radiation doses and is influenced least of all by different dose rate when it is acute single exposure.

• Korean Journal of Poultry Science
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• v.16 no.2
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• pp.105-127
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• 1989

Although poultry industry in Japan has been much developed in recent years, it still needs to be developed , compared with developed countries. Since the poultry market in Korea is expected to be opened in the near future it is necessary to maximize the Productivity to reduce the production costs and to develop the scientific, technologies and management organization systems for the improvement of the quality in poultry production. Followings ale the summary of poultry industry in Japan. 1. Poultry industry in Japan is almost specized and commercialized and its management system is ： integrated, cooperative and developed to industrialized intensive style. Therefore, they have competitive power in the international poultry markets. 2. Average egg weight is 48-50g per day (Max. 54g) and feed requirement is 2. 1-2. 3. 3. The management organization system is specialized and farmers in small scale form complex and farmers in large scale are integrated.