• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.4
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• pp.233-238
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• 1978

Rainbow trout were reared in a stainless steel aquarium from Nov. 11, 1977 to June 12, 1978, and the following results were obtained : 1. The volume of water was about $400\iota$ in a aquarium measuring $1m\;(Length)\times1m\;(Width)\times67cm(Height)$ and water depth 40 cm. Water was supplied for about 16 hours daily at a rate $3\iota/min$ and was drained through the conical settling part in the middle of the aquarium bottom. Filter tank was about $23cm(W)\times23cm(L)\times40cm(D)$ and contained pebbles 30 cm in depth. Water recirculation rate was at)out $1,030\iota/hr$, or 2.6 turn-over per hour. 2. During the first period (77 days), the trout grew from 88.3g to 229g in average, the total weight attaining 30.7kg. The food coefficient was 1.249, average daily increment 243.3g, average daily growth rate 1.245%, and the mortality was 2 smallest fish weighing 53 g, owing to unknown reason. During the second period (135 days), the trout grew from 239g to 555g in average, the total weight attaining 57.2 kg. The food coefficient was 1.447, average daily increment 279.8g, average daily growth rate $0.65\%$ and the mortality was 31 fish weighing 11,255 g, owing partly to miss-handling and partly to disease. 3. The feed consisting of fully domestic materials was prepared in this laboratory, and the feed conversion was not inferior to high protein commercial feed available in foreign countries. 4. The result of whole period for 212 days was 56.5 kg in gross increment, and based on this result, when $1\iota/min$ full day inflowing water available, the net production will become 28.25 kg. So, if a 5000kg production is planned, $180\iota/min$ or about $10.8m^3/hr$ be reauired, and the production in value frill become 15million won at local price at the expense of about 5.3 million won. From the result of this experiment, rainbow trout is feasible for commercial production in Korea with relatively small amount of well water and simplified water recirculation system.

• Korean Journal of Ecology and Environment
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• v.44 no.3
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• pp.253-263
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• 2011

This study was conducted to gain preliminary data for restoration and management of constructed small-scale ponds in paddy fields through analysis of their physicochemical and biological properties. A field survey was performed at 13 small-scale ponds located in paddy fields from August 2009 to October 2010. Structural properties, water quality, soil characteristics and fish fauna were measured. Results showed that small-scale ponds without frames might lose their function over time because of crumbling walls. Therefore, it is necessary for these ponds to have frames for soil protection and sustainable maintenance. Chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) concentration were higher than the water quality standard for agricultural water in small-scale ponds. In particular, TN concentration was 8.03 mg $L^{-1}$ and over 8 times the water quality standard because of the presence of livestock such as cows and pigs in the study areas. Sand, organic matter and available phosphorus contents of soil in small-scale ponds was 53.4${\pm}$16.6%, 21.8${\pm}$9.74 g $kg^{-1}$ and 12.8${\pm}$7.59 mg $kg^{-1}$, respectively indicating that sand and available phosphorus contents were suitable for plants in small-scale ponds, but organic matter contents was somewhat low in newly constructed small-scale ponds, and would take some time to stabilize for plant growing. Fish fauna was not diverse with only 4 species at all sites surveyed. Collected fishes share a common feature that they all inhabit paddy fields or canals with shallow water depth. In this study, all ponds were not linked to the streams and canals around them. It appears that connection to adjacent streams was the major factor controlling fish fauna in small-scale ponds. The results of statistical analysis were classified into three groups. Factor 1 was 26.3%, which shows a structural properties such as area and depth of small-scale pond. As for factor 2, it appears on 20.1%, showing water quality like a TP, suspended solids (SS) and COD. Small-scale ponds were classified into three groups by factor scores. Group I consisted of 6 small-scale ponds, which were larger than the others. Group III had higher water quality than the others. We conclude that the most important points to be considered for restoration and management of small-scale ponds is connection with adjacent streams or ditches and depth and size of the small-scale pond.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.70-75
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• 1998

A model of pond system is developed for treatment and recycling of excreta from twenty-five adult dairy cattle. It is composed of wastewater treatment ponds and small fish ponds. Those are three facultative ponds in series; primary-secondary-tertiary pond and these are designed to rear carps without feeding. A pit is constructed at the bottom of primary pond for efficient sludge sedimentation and effective methane fermentation. It is contrived to block into it the penetration of oxygen dissolved in the upper layer of pond water. The excreta from the cattle housed in stalls are diluted by water used for clearing them. The washed excreta flow into the pit. The average yearly $BOD_5$ concentration of influent is 398.7mg/l. That of the effluent from primary, secondary and tertiary pond of the system is 49.18, 27.9, and 19.8.mg/l respectively. Approximate 88, 93, and 95 % of BOD5 are removed in each pond. The mean yearly SS concentration of influent is 360.5 mg/l That of the effluent from each pond is 53.4, 45.7, and32.7mg/l respectively. Approximate 86, 88, and 91% of SS are removed in each pond. The $BOD_5$ concentration of secondary and tertiary pond can satisfy 30mg/l secondary treatment standard. The SS concentration of effluent from tertiary pond, however, is slightly greater than the standard, which results from activities of carps growing in the pond. The average yearly total nitrogen concentration of influent is 206.8mg/l and that of the effluent from each pond is 48.6, 30.8, and 21.0mg/l respectively. Approximate 74, 88, and 90% of total nitrogen are removed in each pond. The mean yearly total phosphorous concentration of influent is 20.7mg/l and that of the effluent from each pond is 5.3, 3.2, and 2.1mg/l respectively. Approximate 97, 98, and 99% of total phosphorous are removed in each pond. The high removal of nitrogen and phosphorous results from active growth of algae in the upper layer of pond water. Important pond design parameters for southern part of Korea -- areal loading of BOD5, liquid depth, hydraulic detention time, free board, and pond arrangement -- are taken up.

• Korean Journal of Organic Agriculture
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• v.10 no.3
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• pp.87-99
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• 2002

The development of insecticidal soaps made by various fatty acids and organic control for insect by using of insecticidal soap(fatty acid salts) were employed. And the results were as follows: 1. To determine the input volume of potassium hydroxide for saponification of fatty acids, there were compared to individual acid value of fatty acids. in case of coconut fatty acids for saponification was 266.3 mg of potassium hydroxide(266 g/1kg of fatty acid) was calculated. 2. To make the 25% soap content by coconut fatty acids, there was required for the 266g of potassium hydroxide and 3,459 liter of soft water. Then the liquor of soap was 4,644 liter. 3. The progress of insecticidal soap made by fatty acids was accomplished indirect heating and stirring reactor (1)to make the volume of potassium hydroxide solution and warming up(90$^{\circ}$) (2)input volume of individual fatty acid (3)more than 30 min stirring reaction (4)cooling progress. 4. Insecticidal value of insecticidal soap was observed more than 92% the dilution of 50 dilution solution in consecutive 5 days of 2 treatments of the 25% soap made by coconut fatty acids on the red pepper. And insecticidal value of insecticidal soap was observed more than 94% the 100 dilution solution in consecutive 5 days of 3 treatments of the 25% soap made by coconut fatty acids on red pepper and cabbage. 5. The treatment of two times of 25% soap made by coconut fatty acids at the 50 dilution solution and 100 dilution solution in spider mite on red bean has 100% insecticidal value. 6. There was no observation phytotoxic sypmtons on red pepper in field, except for 25% soap made by carprylic acid. 7. Over the two times over 0.1% in addition of isopropyl alcohol was to improvement the insecticidal effect, but there was no effect in addition of diatomaceous earth.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.177-184
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• 2012

This experiment was carried out to investigate soil properties and the requirement of livestock manure compost in a large-scale environment-friendly agricultural complex (EFAC), Gosan, Wanju-gun, Jeonbuk. Total cultivation area of major crops was 2,353 ha. This complex area included different types of environment-friendly cropping sections (402.9ha) and livestock farming including 21,077 Korean beef cattle, 1,099 dairy cow, and 32,993 hog. Amount of livestock waste carried in to Resource Center for Crop and Livestock Farming (RCCLF) was 32 Mg per day and the production of manure compost was 9,600 Mg per year. The manure contained 1.4% total nitrogen (T-N), 2.7% phosphorus as $P_2O_5$, 2.1% potassium as $K_2O$, 0.9% magnesium as MgO, 2.5% calcium as CaO. Amount of compost used in the EFAC was 6,588 Mg per year. Soil pH values in the EFAC were varied as follows: 78.1% of paddy field soil, 58.2% of upland soil, 60.3% of orchard field soil, and 62.1% of greenhouse soil were in proper range. For the content of soil organic matter, 41.7% of paddy field soil, 46.5% of upland soil, 40.5% of orchard field soil, and 81.4% of greenhouse soil were higher than proper range. The content of available phosphorus was mostly higher than proper value on the different fields except upland soil. The contents of exchangeable $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were also exceeded in the orchard field and greenhouse soils. In addition, microbial population, especially aerobic bacteria, in the EFAC was higher than that in regular farming land.

• Journal of Animal Environmental Science
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• v.10 no.3
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• pp.141-154
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• 2004

The solar powered water pump is very ideal equipment because solar power is more intensive when the water is more needed in summer and it is very helpful in the rural area, in which the electrical power is not available. The average so]ar radiation energy is 3.488 kWh/($m^2{\cdot}day$) in Korea. In this study, the automatic control logic and system of the water pump driven by the radiation energy were studied, designed, assembled, tested and analyzed for realizing the solar powered water pump. The experimental system was operated automatically and the cycle was continued. The average quantity of the water pumped per cycle was about 5,320 cc. The cycle time was about 4.9 minutes. The thermal efficiency of the system was about $0.030\%$. The pressure level of the n-pentane vapour in flash tank was 150$\%$450 hPa(gauge) which was set by the computer program for the control of the vapour supply. The pressure in the condenser and air tank during cycles was maintained as about 600 hPa and 1,200 hPa respectively. The water could be pumped by the amount of 128kg/($m^2{\cdot}day$) with the efficiency of $0.1\%$ and the pumping head of 10 m for the average solar energy in Korea.

• Investigative Magnetic Resonance Imaging
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• v.3 no.2
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• pp.173-178
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• 1999

Purpose : To evaluate the usefulness of functional MRI (fMRI) of visual cortex in patients with ischemic infarction in the occipital lobe. Materials and Methods : Four patients with the symptoms and signs of visual cortical ischemia were included. Functional MRI was performed by 2D-FLASH technique with the parameter of 90/56msec TR/TE, $40^{\circ}$ flip angle, $240{\times}240{\;}FOV,{\;}64{\times}128$ matrix number, 8.32 seconds acquisition time, 8mm slice thickness. An axial slice including both visual cortices was selected and alternative activation and resting of the visual cortex was performed using red color photostimulator. all patients undertook visual field test, and vascular abnormality was examined by MRA (n=4) and DSA (n=2). fMRI results were compared with the results of a visual field test, conventional MRI and cerebral angiography. Results : On fMRI, decreased activity of the visual cortex was found in the occipital lobe corresponding to stenosis of the posterior cerebral artery or its branch noted on angiogram. However, 2 of 4 patients showed no abnormal findings on conventional MRI. Visual field defect was noted in 3 patients, one and of whom showed no abnormality on conventional MRI and diffusion-weighted image, but revealed decreased activity in the corresponding visual cortex on fMRI. Conclusion : fMRI may be a sensitive method for detection of the status of decreased blood flow or vascular reserve which other methods can not.

• Journal of Wetlands Research
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• v.10 no.2
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• pp.115-128
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• 2008

Various human activities such as the Urbanization and Industrialization are estimated the main factors to pollute the stream. Now days, numerous studies are carried out for managing non-point sources which have un-effect on water quality of streams by land-use and livestock. In case of Korea, a matter of concern that the management of Pal dang reservoir - the main water resources of the national capital region - has been occurring. Especially, large-scale constructed-wetlands are planned and constructed at the end of Kyoung-an stream. Additionally a lot of sewage treatment plants are newly installed and extended in this watershed. According to these efforts, water quality of Kyoung-an stream is predicted that would be improved. But the more detail and scientific analysis should be carried out for the water quality improvement, because, existing water quality improvement projects are not involved to analyze root of water quality deterioration and improvement plans. Therefore, this study aims to select suitable areas for constructed-wetlands and to calculate size of the constructed-wetlands for water quality improvement in Kyoung-an stream through the geographical pollutant distribution analysis and land-use pattern analysis by high resolution satellite image and suitable area analysis of constructed-wetlands by GIS(Geographic information system). The progress of this study is (1) to select maximum pollutant loaded area by geographical analysis based on water quality data, (2) to analyze land-use patterns using high resolution satellite image, (3) to select suitable areas of constructed-wetlands, (4) to calculate area and volume of chosen constructed-wetlands using GIS. Basically, sizes of constructed-wetlands are induced through the constructed-wetlands design index based on treatment ratio(provided by Korea Water Resources Corporation). As a result of this study, two areas are selected to construct constructed-wetlands. One of the area was $127,586m^2$ near by Yong-in sewage treatment plant, and the other area was $1,647m^2$ near by Ju-buk stream and Dae-dae stream.

• Journal of Mushroom
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• v.2 no.2
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• pp.76-87
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• 2004

This experiments were conducted to study on the economic analysis of Phellinus spp.(Comercial name: Sanghwang mushroom). These results were as follows: Phellinus spp. can be cultivated about 4 years by one time inoculation. This mushroom has been cultivated by the method of burying log into the soil(BM) at the first time. Recently, however, the method of hanging log on the shelves in the house(HM) is used, because HM has more advantage than BM that HM can be cultivated more pieces of logs than BM. On the other hand, HM is required to invest more 5,678,230Won for the equipments than the BM. And also, HM is required 14,400 pieces(2.8 times) more log numbers than BM 5,000 pieces. Also, HM is required more 3,680,000Won to purchase log, 1,104,000Won to purchase spawn. The cost of production is required to 20,180,971Won for BM, and 37,953,825Won for HM. Accordingly, product cost of HM is 1.9 times higher than BM. The operating cost is required to 1,207,712Won for BM, and 24,075,432Won for HM. Accordingly, operating cost of HM is 2.0 times higher than BM. The net income is 580,940,000Won for BM, and 1,683,300,000Won for HM. Accordingly, net income of HM is 2.9 times higher than BM. The income is 589,040,000Won for BM, and 169,718,000Won for HM. Accordingly, income of HM is 2.9 times higher than BM. In conclusion, HM is required 2.8 times more logs. HM has 1.03 times more products per a piece of log. HM has 1.9 times more production cost, and 2.0 times more operating cost. As you read above, HM and BM have two different aspects. BM is required less investment cost than HM, but BM has lower income because of the different capacity of production. By the comparing those two methods, HM is resulted more efficient method for the producing mushroom. Only in the side of cash flowing, the cash expenditure of BM is required less money at first year. But it has no production at first year. BM would get the income after 2 years buring the logs. The cash expenditure of HM is required much money for the equipments and the logs at first year, but HM would get the income at first year.

• Journal of the Korean Arthroscopy Society
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• v.6 no.1
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• pp.21-24
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• 2002

Purpose : The purpose was to assess the result of arthroscopic management of the septic arthritis on the knee in compromised patients. Materials and Methods : Fourteen patients with septic knee were analyzed. The mean age was 55 years and the mean follow-up period was 14.6 months. Underlying diseases included 4 cases of diabetes, and history of direct acupuncture in 4 cases. Clinical stage of septic arthritis was judged by $G\ddot{a}chter's$ classification, which was determined by arthroscopic findings. After arthroscopic irrigation and debridement, we observed the results of laboratory data and improvement of clinical findings. Results : Causative organism was identified in 7 cases and no organism was detected in the remaining 7 cases. Stage I was 1, stage II 8, stage III 4, and stage IV 1, respectively. Eleven of 14 cases were improved by one stage operation. Two cases of stage III were recurred and additional arthroscopic management was done. In 1 case of stage IV, symptom was not improved and needed arthrotomy. The result was unsatisfactory in patients with stage III and IV. Serum erythrocyte sedimentation rate and C-reactive protein were normalized after 29.3 and 20.8 days following the operation, respectively. Clinical symptoms disappeared average 2 days following the operation. Conclusion : Arthroscopic management of acute septic arthritis of the knee would be an effective and satisfactory treatment modality in that its postoperative pain and complications are minimal, and it can be done with ease repeatedly.