• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.170-176
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• 1998

Nitrogen and phosphorus loads from an agricultural watershed of the Yulmun-chon tributary in the Buk-Han River Basin were quantified based on total amounts of water stream flow. The water quality and soil loss were estimated. Levels of the stream were recorded automatically using the water level meter. The flow velocities, along with the cross-sectional areas of the riverbed, were measured to estimate total amounts of water flow at three monitoring sites in this tributary. Water samples were collected at nine sites with two weeks interval from May to August and analyzed for the water quality parameters. Amounts of soil loss were estimated by the USLE. The size of the Yulmunchon watershed was 3,210 ha, of which paddy and upland soil areas were composed about 41%. The total amounts of soil loss from the watershed areas were estimated to be $13,273Mg\;year^{-1}$, showing 53%, 46% and 0.7% of the soil loss ratio from upland, forest, and paddy areas, respectively. Electrical conductivities and Nitrogen concentrations of the stream water were higher in the lower watershed area than in the upper area. Increments of N were higher for $NO_3-N$ than $NH_4-N$. Nitrate nitrogen was the major N form to pollute the water due to the agricultural activity. Total runoff was about 72% of the total precipitation in the watershed. The maximum loads of T-N and T-P due to the runoff were estimated to be 1,500 and $5kg\;day^{-1}$, respectively. Concentrations of $NO_3-N$ and $NH_4-N$ in the runoff were 13.5 and 1.8 times higher than those in precipitation. The N loads were mainly from soil loss, application of fertilizer, and livestock wastes, which were 52% of total N load. Results demonstrated that reduction of fertilizer use and the soil loss would be essential for water quality protection of the agricultural watershed.

• Journal of the Korean Society of Tobacco Science
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• v.18 no.1
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• pp.49-53
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• 1996

This experiment was carried out to study the effect of oxygen on chemical composition and physical properties of tobacco leaves during flue-curing. The results obtained were as follows: Starch content decreased and sucrose content increased with increasing oxygen supply during curing. Glucose and fructose of the cured leaves showed high content at the 5-10% oxygen supply. Amino-N and nitrate-N increased with increasing oxygen supply. Total nitrogen and NH4-N showed the lowest value at the 5-10% and 10-15% oxygen supply in the cutters and leaf, respectively. Chlorophyll and chlorogenic acid increased, and total volatile base decreased with increasing oxygen supply. The activity of α-amylase increased at the latter period of flue-curing, and the maximum activity point were delayed 12 hours with increasing oxygen supply. Shatter index of cured leaves decreased with increasing oxygen supply. It was desirable to supply oxygen during flue-curing for the improvement of chemical and physical properties such as starch, total sugar, chlorogenic acid, and shatter index of cured leaves.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.125-125
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• 2001

Total lipid contents were 0.58∼3.00% in 9 kinds of brown algaes, 0.47∼2.16% in 5 kinds of red algaes and 0.55∼2.99% in 2 kind of green algeas, respectively. Fatty acid compositions of the algaes were determined by gas liquid chromatography. Total polyenes and n-3 polyenes of linoleic acid(18:3), stearidonic acid(18:4), eicosapentaenoic acid(20:5) and docosahexaenoic acid(22:6) were 3.88∼57.57% and 1.46∼25.67% in the brown algaes, 5.30∼39.75% and 1.17∼21.91% in the red algaes, and 7.76∼19.27% and 3.67%∼10.61% in the green algaes, respectirely. The fatty acid contents and compositions of total polyenes and n-3 polyenes were vary different in the algae groups and sepecies.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.484-487
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• 2001

Runoff, sediments and nutrient losses were studied under different patterns of paddy field management: (1) fall and spring plowing (PL); (2) fall plowing for half of plot and spring plowing (SPL); (3) no-till for fall and spring plowing (NPL) during the non-cropping period in the southern Korea. Sediment losses from PL plot were 25% more than those from NPL plot. There was significant difference in nutrient losses via runoff water and sediment according to plowing practice (P < 0.01). Losses of total-N, ammonia-N, nitrate-N, total-P from NPL plot were larger than PL and SPL plots during study period. Sediment and total-P losses from SPL plot were close to those of PL plot.

• Journal of the Korean Society of Tobacco Science
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• v.9 no.1
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• pp.27-33
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• 1987

This study was carried out to investigate the effect of cultural practices on the nicotine and sugar contents in flue-cured tobacco(NC82), and the relationship between them. Significant reduction I sugar content and ratio of total sugar to nicotine(ratio, S/N) were observed with increased fertilizer, lower topping height, late transplanting and decreased application of male hydrazide(MH). Significant increases were observed in nicotine content with increased fertilizer and lower topping height. A positive correlation was found between total sugar content and plant density. A negative correlation was found between nicotine and total sugar contents for 8-years. An increase of 1.0% nicotine in the cured leaf would result in a 4.8% reduction in total sugar. The most desirable contents were 2.7% for nicotine and 19.0% for total sugar(S/N=7).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.4
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• pp.71-74
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• 1986

The author tried to clarify the distribution of the total length and body weight of the file h, Navodos modcstus, caught by trawl net during July, 1984 in the southern sea korea. Among the catches of five times fishing operation, 1540 individuals were randomly sampled for the measurement. The results are summarized as follows; " The distribution of total length showed bimodal type, wbich was able to analyzed into two normal distributions N(17.46, 1. 02^2) and N(22.09, 1. 77^2). And smaller group was much than older one. The age of the sample estimated from the total length distribution of. smaller group was 1. 5 to 2, and the larger group 2. 5 to 4. The relationship between the total length and the body weight can be presented as following equation: $$W=0.01726 L^{2.8507}$$ ' or $$W= 0.01109 L^{3.0}$$ or $$W= 0.01109 L^{3.0}$$.

• Journal of Chest Surgery
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• v.22 no.2
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• pp.202-211
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• 1989

We experienced a series of animal experimental studies of the total artificial heart in 1988. So called, "Korean Heart* was used in this study, which is developed and fabricated in the Department of Biomedical Engineering, College of Med., S.N.U.. "Korean Heart" is a Rolling-Cylinder Motor-Driven type which is a newly developed electromechanical heart over the shortcomes of the previous artificial hearts, especially pneumatic type. The advantages of the "Korean Heart" are total implantability, quiet and smooth movement, small size fittable in oriental people, etc. The animal experiments were performed two times, as an assist device in sheep and total artificial heart implant experiment in calf weighing 100 kg. After total implantation, the artificial heart was well functioned in movement and hemodynamic control. So that, the calf was recovered excellently, which was able to stand up by herself and take an oral intake. Total survival time was 100 hours and the cause of death was a sudden pumping failure [electrical connection problem]. Several postoperative laboratory results almost within normal limits and no hemolysis, but in autopsy, the multiple thromboembolic findings were seen at the lung and kidney.n at the lung and kidney.

• Advances in pediatric surgery
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• v.6 no.2
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• pp.128-133
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• 2000

Persistent cloaca in a female newborn is one of the most complex and challenging anorectal malformation. The incidence is about 10% of all anorectal anomalies. Treatment of cloacal malformations has evolved during the past 40 years. However, it still remains one of the most difficult operations. In 1997, Pena reported a new procedure called "Total urogenital mobilization". We have repaired 3 cases of cloacal anomaly using "Total urogenital mobilization". The operations were performed between age 15 and 28 months. The length of the common channels was 2.5 - 3.0 cm. Two cases had double vaginas and one of them also had double uterus. The operation time was 4-5 hours and no major complications occurred. Functional and cosmetic results were satisfactory.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.3
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• pp.465-468
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• 1992

Urinary purine derivatives and creatinine excretion was measured in a total of 4 white Alpine sheep. They were given diets 718 to 1060 g/kg dry matter (DM) of roughage. The crude protein content of this diets was on average $93.87{\pm}5.57g$ in kg DM. Purine derivatives-N excretion increased linearly with incremental DM intake and was significantly correlated (n = 16) with amounts of digestible organic matter (DOM) intake: allantoin-N (mg) = 1.205 (${\pm}0.070$) $\times$ DOM (g) - 136.709 (${\pm}37.399$), r = 0.9770, RSD = 22.97; uricacid-N (mg) = 0.131 (${\pm}0.041$) $\times$ DOM (g) + 11.380 (${\pm}21.881$), r = 0.6306, RSD = 13.44; Hypoxanthine-N (mg) = 0.049 (${\pm}0.014$) $\times$ DOM (g) - 28.640 (${\pm}7.708$), r = 0.6544, RSD = 4.73; total purine derivatives-N (mg) = 1.385 (${\pm}0.083$) $\times$ DOM (g) - 90.261 (${\pm}44.552$), r = 0.9706, RSD = 27.47. Microbial protein synthesis per kg DOM was estimated of 113 g. The urinary creatinine-N excretion was on average 9.10 mg/kg live weight (LW) with a standard error of 0.12 mg creatinine-N per kg LW. The excretion of creatinine excreton was not related to feed intake. Daily creatinine excretion (mg/d) was calculated from individual LW measurements and the average creatinine excretion (mg/kg LW). It was possible to predict the daily urinary purine derivatives excretion (r = 0.9720 for allantoin, r = 0.9886 for total purine derivatives) from the ratio of purine derivatives (mg/100 ml) and creatinine (mg/100 ml) in the urine and the daily creatinine excretion.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.3
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• pp.93-102
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• 1989

With an objective to provide basic information for the management and the prediction of eutrophication in lentic water Systems, total amount of Kjeldahl nitrogen(T-N) and phosphorous(T-P) from irrigated water and drained water from flooded paddies were investigated during the rice growing period of 1988. A 29.3 ha paddies near Jungnam-myun, HwaSung-gun, Gyungi Province, Korea was instrumented for measuring runoff and sampling irrigated water and drained water from paddies. The following conclusions may be drawn from the result of this study. 1.During 115 days of investigation, T-N load for paddies was 362.6kg and T-P 63.44kg.These would be converted to 12.4kg T-N/ha and 2.17kg T-P/ha, respectively. 2.The T-N and T-P loadings in different periods showed a significant difference. The 25% of T-N loading was drained soon after fertilization period and 60% was drained during the rainy season from July 5 to July 24. 3.Annual loadings from paddies could be calculated to 30kg T-N/ha/year and 52kg T-P/ha/year considering non-measurement periods. 4.After the rainy season, the nutrient loads from drained water showed much less than those from irrigated water, and it may be suggested that the paddies would act as a stabilization pond. 5.The average concentrations of nutrients at 0.9km downstream from investigated paddies were 2.02(T-N) mg/l and 0.52(T-P) mg/I, which were 1.82(T-N) mg/l and 0.056(T-P)mg/l lower than those of drained water from paddies.