• 한국환경보건학회지
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• 제16권1호
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• pp.29-43
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• 1990

The purpose of this study is to investigate the vairous change in the toxicity of cadmium by the simultaneous administration of selenium and zinc, which have been reported to change -the toxicity of cadmium through the interaction with cadmium, to rat. For the experiment, 42 rats of Sprague-Dawley strain were used. The experimental groups were divided into 6 groups: a control group, a cadmium (100ppm) alone treatment group, a cadmium (100ppm) and zinc (100ppm) combined treatment group, and three cadmium (100ppm), zinc (100ppm) and selenium (1, 4, and 8ppm) combined treatment groups. The rats were allocated seven to each group and observed for seven weeks. The results of experiment are as follows: 1. The food consumptions of each group were reduced, compared with a control group, especially, in a cadmium and zinc combined treatment group and a cadmium $\cdot$ zinc and selenium(1ppm) combined treatment group to the significant level compared with a control group (p < 0.05). The water consumptions of each group were reduced to the very significant level compared with a control group (p < 0.01). The feed efficiencies of each group were lower than a control group, and among them the highest group was cadmium $\cdot$ zinc and selenium (8ppm) combined treatment group as 90% of a control group. 2. In all groups, the weight gains were highest in the second week and the total weight gains were reduced to the very significant level compared with a control group (p < 0.01). 3. In all groups, the relative weights of liver were reduced, compared with a control group, especially, a cadmium alone treatment group was reduced to the significant level (p < 0.05). The relative weight of kidney was high to the significant level in a cadmium alone treatment group (p < 0.05) compared with a control group. In all groups, the relative weights of testis were reduced, compared with a control group, but the levels were not significant. 4. The accumulation of cadmium was highest in the kidney and the order of height was in liver, testis and blood, respectively. In all groups, the amount of cadmium accumulation was high to the very significant level compared with a control group (p < 0.01). In liver, the amount of acdmium accumulation in. a cadmium alone treatment group was high to the significant level compared with a cadmium $\cdot$ zinc and selenium (8ppm) combined treatment group (p < 0.05), and in kidney, the amount of cadmium accumulation in a cadmium alone tretment group was high to the very significant level compared with the cadmium $\cdot$ zinc and selenium (4, 8ppm) combined treatment groups (p < 0.01). However, in testis, among the treatment groups the level was not significant and in blood, a cadmium alone treatment group was low to the significant level compared with the cadmium $\cdot$ zinc and selenium (4, 8ppm) combined treatment groups (p < 0.05). 5. According to the histopathological finding on the testis, some of the seminiferous tubules of a group treated with cadmium alone showed severe necrosis and atrophy. But the testis of cadmium $\cdot$ zinc and selenium (8ppm) combined treatment group was similar to that of a control group. From the results of this study, it can be concluded that the repeated simultaneous oral administration of large doses of selenium with the cadmium produces the partial amelioration of cadmium toxicity, whereas zinc does not.

• The Korean Journal of Physiology
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• 제2권1호
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• pp.47-52
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• 1968

Twenty white rabbits anesthetized with nembutal (30 mg/kg) were employed in this experiment. Five of them served as controls; the remaining rabbits as experimental group were subjected to irreversible hemorrhagic shock. Shock was induced by bleeding the animals until mean blood pressure decreased to a level of 50-40 mmHg. This level of pressure was maintained for 3-4 hours, after which the drawn blood was reinfused. The reinfusion of blood caused the elevation of arterial pressure almost the control level for some minutes, after which a gradual and progressive decline of blood pressure became evident. This decline was thought to be the result from irreversible hemorrhagic shock. When mean blood pressure declined to less than 50 mmHg, chest was opened and samples of arterial blood and left ventricular muscle were taken. Left ventricular muscle and blood plasma were analyzed for potassium, sodium, chloride and water content. Blood glucose concentration was determined by Somogyi-Nelson's method. Extracellular and intracellular myocardial water and electrolyte content were calculated on the basis that electrolytes are distributed between plasma water and interstitial water according to Gibbs-Donnan equilibrium. In this calculation extracellular water was substituted for Na space. The findings obtained were as follows: 1. The concentration of blood glucose was 87mg% in the controls and it rose to 222 mg% in shock (P<0.01). 2. Plasma potassium elevated significantly from 3.3 mEq/l in controls to 8.0 mEq/l in shock (P<0.01), while small decreases in sodium (151-146 mEq/l) and chloride (102-96 mEq/l) were observed (P<0.3, P<0.1), 3. The changes of blood water content (83.1-84.3%) and cardiac water content (77.5-78.3 gm/100gm WT) were observed. 4. In control animals myocardial potassium levels which averaged 30.2 mEq/100 gmDT rose significantly to 40.3 mEq/100 gmDT in shock (P<0.01), while moderate decreases in sodium(16.3-14.3 mEq/100 gmDT) were observed in shock. 5. The calculated transmembrane resting potential of left ventricular muscle of control animals averaged 95 mV, while rabbits in shock averaged 77 mV. (P <0.01). The findings of this experiment do not correspond with the conclusions that myocardial depression seems to be the cause of irreversible hemorrhagic shock, because the excitability of heart muscle is elevated. From the point of view that the lowered transmembrane resting potential, the cause of death in terminal stage of irreversible hemorrhagic shock may be ventricular fibrillation. It can't be said, however, that the lowered transmembrane resting potential is responsible for the transition from reversible to irreversible hemorrhagic shock. The marked increase in blood glucose suggested that glycogenolysis in the liver is favorably active in shock.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅲ
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• pp.1295-1298
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• 2003

The steam generator level in a PWR is very difficult to control particularly at low power. And the constant control gain and time value are not adaptive in steam generator level controller. In normal operation constant control gain and time value have no problem. But there is problem at low power. So variable control gains based on the temperature are required. The best control gain is decided by the experienced knowledge. A fuzzy gain tuner is used for the gain tuning. In the design of fuzzy gain-tuner processing, the experienced knowledge is employed for making fuzzy rules.

• 설비공학논문집
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• 제25권3호
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• pp.168-172
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• 2013

A preliminary performance test of a 30RT 2-stage screw heat pump was carried out in order to develop a high performance large-scale unutilized energy source heat pump system, which will be used for district heating and cooling. In this study, two issues of the system operating control were investigated. The first issue is the mode switching control from 1-stage to 2-stage. A stable 2-stage heating operation is guaranteed, only if the load-side water inlet temperature is over a certain value, where the 1-stage heating operation should be done first from a cold start. The second issue is oil level control. An oil shortage problem in the low stage compressor, which depends on the degree of suction superheat, was solved by a proper oil level control scheme.

• 한국물환경학회지
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• 제30권2호
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• pp.206-211
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• 2014

This study was done to find chemicals adequate to control alkalinity and hardness in order to reduce dissolved phosphorus in water bodies like rivers and lakes. Five chemicals were selected for the study: calcite, lime, dolomite, magnesite, and gypsum. Data were obtained from the calculations with MINTEQ model as a function of dosage variations of each chemical. Findings are as follows: Three out of the five chemicals are found to be effective in reducing the dissolved phosphorus, i.e., calcite, lime, and dolomite. Calcite and dolomite are able to lower the phosphorus concentration up to one thousandth fold whereas lime does one hundred thousandths fold. In viewpoint of pH variation, both calcite and dolomite seem to be safe since the pH does not increase over 8.3 even in case of overdose. In the same circumstance, with lime the pH increases beyond 9 which is considered to be the highest pH level for the protection of water ecosystem. Nevertheless it is recommendable to use lime in case where there are some difficulties in water quality control due to algae blooms.

• 동아시아식생활학회지
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• 제14권3호
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• pp.275-282
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• 2004

The quality characteristics of baguette bread added with water extracts of Liriopis tuber(LT) and effect of the diets containing 20% dried and powered baguette with 10% LT on the level of blood sugar and lipids in the diabetes induced rat by streptozotocin were investigated. pH of the dough added with 5∼10% LT was 5.00∼5.03 which were lower than that of control(5.12). The volume of the dough with 10% LT after 2nd fermentation was the biggest. Loaf volume index of the bread with 10% LT was significantly higher than that of control. $L^{*}$ values of outside and inside of the baguette decreased in proportion to the increase of the LT, while the $a^{*}$ values increased. Color of the bread with LT showed light dark-red. There was no significant difference in hardness, but springiness and gumminess were higher in the bread with 10% LT. Sweet taste increased, color acceptability and overall taste were enhanced by addition of LT, but it did not affect the sour and astringent taste. The overeating phenomenon showed in the diabetes rat decreased in the group fed with baguette bread with LT, while feed efficiency increased by feeding of the bread with LT. The level of glucose, neutral lipid and total cholesterol in blood were 118.92,95.47 and 37.42mg/dL in the control group, 245.60, 121.54 and 102.43 mg/dL in the diabetes control, 148.40, 103.25 and 57.63 mg/dL in the baguette diet group, respectively. There was no significant difference of HTR between control group and baguette diet group, while atherogenic index was considerably decreased, which might represent improving and preventing effects of diabetes.s.s.

• Asian-Australasian Journal of Animal Sciences
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• 제6권4호
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• pp.521-526
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• 1993

Two percent of monocalcuim phosphate (MCP) was added to control diet consisted of fish meal (18%), soybean meal (36%) and wheat flour (37%) in order to examine the effects on phosphorus (P) discharge and growth of carp (Cyprinus carpio). Growth trial, during which digestibility measurements were made over 7 days, was conducted for 4 weeks using a recirculated rearing system with a settling column for feces collection. Fishes (initial body weight of about 200 g) were fed five times a day upto satiation with tank controlled at $24-26^{\circ}C$. Fishes fed the diet containing 2% MCP (MCP-2) showed about two-fold improvement on both growth rate and feed utilization, compared to those of fishes fed the control diet; weight gain (129 g vs 62 g), feed conversion ratio (1.20 vs 2.46), protein efficiency ratio (2.09 vs 1.07) and daily growth index (3.70 vs 1.93). However, feed intakes were maintained at the same level (150 g/fish) between the two treatments. Dry matter digestibilities of two diets were relatively low, which were 58 and 60% for respective control and MCP-2 diets due to low digestibility of total carbohydrates. However, the digestibilities of both dietary protein (85%) and lipid (90%) of diets were relatively high. While all the P fed were observed to be discharged from fish fed control diet, the discharge from fish fed the MCP-2 diet was decreased up to less than the half (34.9 g/kg wt. gain) of the control. These present results revealed that the supplementation of dietary P requirement by MCP can not only promote growth performances but also reduce the level of P loading to water which is the primary water pollution indicator.

• 조명전기설비학회논문지
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• 제12권4호
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• pp.6-13
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• 1998

본 연구에서는 증기유량, 중기온도 주 급수 온도 및 유량둥과 같은 외란에 의해 증기발생기의 웅축 및 팽창효 과가 발생하여 수위조절에 어려웅이 발생하는 문제를 신경망-PI제어기를 이용해 효과적으로 제어하는 연구를 하였다. 종래의 PI제어기는 저 출력에서 효과적으로 제어 할 수 없어 기동시는 숙련자의 노련한 기술이 필요한데 반해 본 연구에서 적용한 신경망 PI제어기는 Kp,Ti 파라매터를 외란에 영향을 줄 수 있는 파라메터를 고려하여 신경망을 이용해 튜닝함으로서 웅축 및 팽창효과를 줄이고 외란 및 설정치 변경에 대해 효과적으로 제어 될 수 있음을 실험과 시뮬레이션을 통해 확인 할 수 있었다.

• 한국식품영양과학회지
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• 제32권4호
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• pp.614-620
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• 2003

상엽과 상심자, 구기자, 인삼 등은 당뇨에 효능이 있는 것으로 널리 알려진 약재들이다. 본 실험에서는 기본 실험을 통하여 상엽, 상심자, 구기자, 인삼, 차가버섯의 최적 배합비와 최적의 추출방법으로 엑기스 형태로 만들어진 소당엑스$^{TM}$와 이를 특허 출원한 방법으로 백미에 코팅한 소당미$^{TM}$를 사용하여 시험한 결과 Alloxan으로 당뇨를 유도한 마우스, 정상인, 그리고 당뇨환자 모두에서 혈당이 저하되었음을 확인하였다. 따라서 소당엑스$^{TM}$와 소당미$^{TM}$는 당뇨환자의 혈당 조직 및 합병증 예방에 효과적이므로 당뇨식이요법제로서 이용될 수 있는 건강 식품으로 사료된다.

• 한방안이비인후피부과학회지
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• 제24권2호
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• pp.16-27
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• 2011

Objective : To investigate the effects of Pyeongwi-san-gamibang on atopic dermatitis, this study measured TEWL(transepidermal water loss), observed scratching behaviors and checked levels of Total IgE, IL-4, IFN-${\gamma}$ and conducted skin biopsy on NC/Nga mice with atopic dermatitis. Methods : NC/Nga mice were challenged with DNCB during 5 weeks to develop atopic dermatitis-like skin lesions. The NC/Nga mice with atopic dermatitis were divided into three groups of control group, PW-d, PW-e group. Once a day for 22 days, Pyeongwi-san-GamiBang extract with water was administered for the PW-d group and the extract with 80% ethanol was administered for PW-e group compared with saline solution for control group. During drug administration, sensitization by DNCB had lasted for three times per week. Results : 1. TEWL had no statistical difference among 3 groups. 2. The scratching behaviors had no statistical difference among 3 groups. 3. The levels of Total IgE in PW-d, PW-e group had a statistically significantly higher than that of the control group although difference between the control group and the PW-d, PW-e group were similar. 4. The level of IL-4 had no statistical difference among 3 groups. 5. The level of IFN-${\gamma}$ had no statistical difference among 3 groups. 6. As the observation of toluidine blue stained lesion, both PW-d and PW-e group had lower level of histamine releasement compared with the control group. Conclusion : Result based on these experiments, Pyeongwi-san-GamiBang on atopic dermatitis-like skin inflammation in NC/Nga mice is not effective. But, as the study showed significantly individual differece, we need to repeat these study after supplementing the object number and modified indicator of clinical severity.