• The Korean Journal of Malacology
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• v.15 no.1
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• pp.41-47
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• 1999

From September 1994 to April 1996, we observed the suspending time dependant meat increase (dry weight) for oysters at Pukman Bay in Korea. The oysters which suspended in September increased to 5 g in meat weight (dry weight) by January. Ones in June increased rapidly but lessened during summer and this stagnation of meat increase extended to autumn. It took long time to compensate for the loss of meat weight owing to spawning. Oysters suspended in July or August showed low growth or stagnation due to the high water temperature and spawning activities after suspending. However, meat weight showed sudden increasement after December and achieved 5 g at the late farm period. The meat increase of oysters suspended in October or November was very slow during entire growing period. Most of them did not achieved 5 g during farm period. The negative correlation was observed between meat growth and water temperature in September. Also, there was a high correlation between meat growth and chlorophyll-a. It was believed that deficiency of food organisms in the water column lead slow growth in terms of meat growth, particularly right after transplanting seed oysters to the farm. Our study suggests that proper time for transplanting oysters is between August and mid-September. However, the data indicate that good growth of oysters is depending upon amount of food available in the water column.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.284-288
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• 2004

The response of dissolved oxygen (DO) concentrations caused significant change in root number, root length, coleoptile length, shoot length and leaf age of seedlings. The genotypic difference in the effect of DO also highly significant (P<0.01) for all of the seedling traits. The number and length of root were extremely inhibited at the condition of $0.39\pm0.09$ DO concentration. While the coleoptile elongated markedly in the lowest DO concentrations, the shoot did not develop. The root growth was improved slightly at the $1.39\pm0.27mg L^{-1}$, however, there were no difference among genotypes at these two low DO concentrations. As the DO concentration become higher, the growth of root and shoot was improved remarkably. Root number, root length and shoot length was significantly different between $20\;and\;30^{\circ}C$ in DO rich and normal conditions, the development of those traits were apparently accelerated in high water temperature, however those traits of seedlings in DO deficiency were not different between the two temperatures except for shoot length. On the other hand the coleoptile length was not affected by the stagnant water temperature; it was stimulated by the low DO concentration. The competition of DO was greater as the seedling density was increased in the stagnant water, therefore the seedlings grown under high density have long and white coleoptiles, and the growth of roots and shoots was retarded severely.

• The Journal of Internal Korean Medicine
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• v.10 no.1
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• pp.81-91
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• 1989

It has been known for a long time that Palmiwon water extract can be prescribed for the treatment of deficiency of Yang in oriental medicine. But the exact mechanism of it has not been Known yet. In the present experiments, it was attempted to explain the effect of Palmiwon water extract on the serum Hormone level in rabbits and the antifatigue in mice. Palmiwon water extract oral intake showed a increase of serum hormone level in rabbits and the effects of the antifatigue in mice. The results obtained were as follows. 1. The administration of this medicine was observed to cause continuously a significant increase of the testosterone content in the serum from the 7th day to the 21th day. 2. The estradiol centent in the serum, as compared with the control experiment, was seen to increase significantly by the administration of this medicine from the 7th day to the 21th day. 3. The LH and FSH content in the serum, as compared with the control experiment, indicated a tendency toward an increase by the administration of this medicine from the 7th day to the 21 th day, but with no significant difference. 4. In the effect to Palniwon on the antifatigue in mice, swimming time was prolonged in both sample A, B groups than control group, and significance revealed in both sample A, B groups. These data suggest that Palmiwon water extract can increase serum hormone level and that it can have therapeutic effectiveness to the antifatigue.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.200-214
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• 1994

In order to clarify the benthic environmental properties as a part of a study on the macrobenthic community in the Chinhae Bay System, water temperature, salinity and dissolved oxygen (DO) in surface and bottom water layers, mean grain size (${\phi}$) and sediment organic carborn (SOC) in surface sediment were analyzed at twelve stations during the period from June 1987 to May 1990. A high sediment organic carbon and hypoxic condition in bottom water due to the development of summer stratification and fine sediment texture toward the inner bay were important environmental characteristics of Chinhae Bay. Hypoxic conditions began to develop in the inner bay from May, and gradually spread toward the outer bay in summer with a peak in September when half the bay was affected by this oxygen deficiency. Recovery from this hypoxic condition in the bottom layer was observed from the beginning of autumn together with a disappearance of the summer stratification. Principal component analyses were carried out from the following five environmental variables:mean water temperature, salinity, dissolved oxygen in the bottom layer and mean grain size, sediment organic carbon in surface sediment. The twelve stations were classified into four areal groups based on the analyses. The division of the areal groups had high correlations to the sediment organic carbon content.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.771-775
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• 2008

Concerns related to protecting, identifying, and isolating of subsystems of a water distribution network have led to the realization of the increased importance of valves in the system. The most important purpose of valves in water distribution systems is to isolate subsystems due to breakage, maintenance activities, or contamination. A subsystem called segment is isolated by the closure of adjacent valves and an efficient algorithm should identify the adjacent valves to minimize the pipe failure impact. In this paper, an algorithm to identify adjacent valves to be closed to isolate a subsystem from the remainder of a network in case of a pipe failure is presented. An application to the water distribution system in Ottawa, Canada demonstrates the developed algorithm efficiently locates the adjacent valves for the isolation of a broken pipe.

• Journal of Environmental Science International
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• v.14 no.4
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• pp.397-404
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• 2005

In order to study the temporal variations of nutrients and chlorophyll-a in the Bottol Bada, three field observations were carried out on 20, 23 and 26 July, 2004. The low N:P values exhibit nitrogen deficiency during the periods of observation. This result is not representative of typical summer environment in the southern coast of Korea. The possible mechanisms are as follows: 1) The freshwater inflow was not sufficient for the supply of nitrogen because the total precipitation was 11.9 mm in July, 2004. This amount is no more than $5\%$ in normal precipitation in July. 2) There was an inflow of oceanic water under the subsurface into the Bottol Bada. Even though the oceanic water comprises more nutrients, it produces the stratification between the surface and the subsurface water and seems to prevent the supply of nutrinets to the surface layer. 3) The high chlorophyll-a concentration of $1.2 {\cal}ug/L$ was shown near the narrow channel between Gae-do and Geumo-do. This seems to be resulted from the inflow of water from Gamak Bay.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.11
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• pp.915-922
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• 2006

Considering heat pipe design principles in fabrication and operational performances, water is one of the most recommended working fluids to make mid to low tempera lure heat pipes. But the conventional water heat pipes might encounter the failure in a cold start-up operation when socked at a chilling temperature lower than the freezing point. If they are subjected to a heat supply for start-up at a temperature around $-20^{\circ}C$, the rate of the vapor flow and the corresponding heat transfer from the evaporator to the condenser is so small that the vapor keeps to stick on the surface of the chilling condenser wall, forming an ice layer, resulting in a liquid deficiency in the evaporator. This kind of problems was resolved by Kang et al. in 2004 by adopting a gas loading heat pipe technology to the conventional water heat pipes. This study was conducted to examine a chilling start-up procedure of gas loading heat pipes by investigating the behaviors of heat pipe wall temperatures. And the thermal resistance of the gas loaded heat pipe that depends on the operating temperatures and heat loads was measured and examined. Two water heat pipes were designed and fabricated for the comparison of performances, one conventional and the other loaded with $N_2$ gas. They were put on start-up test at a heat supply of 30 W after having been socked at an initial temperature around $-20^{\circ}C$. It was observed that the gas loaded one had succeeded in chilling start-up operation.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.634-640
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• 2007

Our previous study suggested that n-3 fatty acid deficiency was associated with significantly reduced spatial learning as assessed by Morris water maze test. Here we investigated an effect of n-3 fatty acid deficiency on rat brain, retina and serum fatty acyl compositions at 15 wks age using a first generational artificial rearing technique. Newborn Rat pups were separated on day 2 and assigned to two artificial rearing groups or a dam-reared control group. Pups were hand fed artificial milk via custom-designed nursing bottles containing either 0.02%(n-3 Deficient) or 3.1% (n-3 Adequate) of total fatty acids as a-linolenic acid(LNA). At day 21, rats were weaned to either n-3 deficient or n-3 adequate pelleted diets and fatty acid compositions of brain, retina and liver were analyzed at 15 wks age. Brain docosahexaenoic acid(DHA) was lower(58% and 61%, P<0.05) in n-3 deficient in comparison to n-3 adequate and dam-reared groups, receptively, while brain docosapentaenoic acid(DPAn-6) was increased in the n-3 deficient group. In retina and serum fatty acid compositions, the decreased precentage of DHA and increased precentage of DPAn-6 were observed. These results suggested that artificial rearing method can be used to produce n-3 fatty acid deficiency in the first generation and that adequate brain DHA levels are required for optimal brain function.

• Current Research on Agriculture and Life Sciences
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• v.21
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• pp.1-9
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• 2003

Plants are often subjected to periods of soil and atmospheric water deficit during their life cycle. To find critical levels for identification of tolerant rice variety to salt- and drought-stresses, we investigated the water deficiency in the leaf of a Dongjinbyeo (DJ) cultivar, identified as intolerant variety, subjected to NaCl- and Polyethylene glycol 6000 (PEG)- treatments. The relative water content and water potential in leaf of DJ plant sharply declined along the high concentration and time after treatment in NaCl- and PEG-treated rice plants. To elucidate the method of simple screening of tolerant variety to salt- and drought-stresses, we examined the relationship between relative water content and water potential of leaves in NaCl- and PEG-treated rice plants. The relationship between relative water content and water potential in leaf of DJ plant showed the highest correlation in 80 mM NaCl-treatment, and showed high correlation only 8% PEG treatment. These results indicate that the critical level of salt stress for screening of tolerant rice was 80 mM NaCl at 48 h after NaCl treatment, and the critical concentration of drought stress for screening of tolerant rice was 8% PEG at 96 h after PEG treatment.

• The Journal of Internal Korean Medicine
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• v.18 no.2
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• pp.268-295
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• 1997

Sweating is natural phenomenon necessary for the regulation of an individual's body-temperature. The secretion of sweat is mediated by a portion of our vegetative nervous system(the sympathetic nervous system). In some people, this system is working at a very high activity level, far higher than needed to keep a constant temperature. This condition is referred to as hyperhidrosis. Especially excessive sweating of the hands and the feet is palmoplantar hyperhidrosis or volar hyperhidrosis. This is by far the most distressing condition. It was founded that the first important cause of this was emotional factor. The hands are much more exposed in social and prefessional activities than any other part of our body. Many individuals with palmoplantar hyperhidrosis are limited in their choice of proffession, because unable to manipulate materials sensitive to humidity or reluctant to shake hands; some patients arrive to the point to avoid social contact. The occidental medical treatments for palmoplantar hyperhidrosis include application of topical agents(chemical antiperspirants such as aluminum chloride), iontophoresis(treatment with electrical current), or surgery(thoracic sympathectomy). It was reported that the most effective treatment was thoracic sympathectomy. So this study was started to find the easy and effective oriental medical treatments against the occidental medical treatments through the oriental medical literature. The occidental medical idea for palmoplantar hyperhidrosis is only limited in neurologic system, so surgery is the best treatment. But the oriental medical idea for palmoplantar hyperhidrosis is much wider, so the oriental medical causes and treatments for this are able to be veriety. And the oriental medical teatment is freely in treating the patients of palmoplantar hyperhidrosis, because entire idea including pulse, facial color, mental condition, constitution and other symptom exists in the oriental medicine. The results of a bibliographic study of causes and treatments for palmoplantar are as follows; 1. The main causes of pa1moplantar hyperhidrosis are heat in the stomach, damp-heat in the spleen and the stomach, insufficiency of the spleen-qi and the stomach-qi, deficiency of the spleen-yin and the stomach-yin, and the others are the stomach-cold syndrome, stasis of blood and dyspepsia in the stomach, disorder of the liver-qi, deficiency of the heart-yin and the kidney-yin, deficiency of the heart-yang and the kidney-yang, stagnated heat in the liver and the spleen, the lung channel-heat etc. 2. The main methods of medical treatments for palmoplantar hyperhidrosis are clearing out the stomach-heat, eliminating dampness and heat in the spleen and the stomach, invigorating the spleen-qi and the stomach-qi, reinforcing the spleen-yin and the stomach-yin, warming the stomach, relaxing the liver and alleviating of mental depression and tonifying the heart and the kidney etc. 3. The main prescriptions of palmoplantar hyperhidrosis are Taesihotang, Palmultang-kakam, Samyeongbaechusan, Chongbisan, Sasammaekmundongtang, the others are Leejungtang, Hwangkikonjungtang, Seungkitang, Boyumtang, Baekhotang, Chongsimyonjayum, Moyrosan, etc. 4. Local medicine for external use are liquid after boiling alum in water for about 1 or 2 hours, liquid after boiling alum and pueraria root in water and liquid after boiling stragalus root, pueraria root, ledebouriella root and schizonepeta in water, etc. 5. The methods of acupuncture therapy include invigorating Bokyru, Yumkuk and purgating Hapkouk, or invigorating Bokyru, Kihae and purgating Hapkouk, or steadying Hapkouk, Nokung.