• Archives of Pharmacal Research
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• 제11권1호
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• pp.65-73
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• 1988

The effects of clonidine on the negative chronotropic response induced by stimulation of vagus nerve were studied in the presence of propranolol in reserpinized and anesthetized rats. When the heart rate was decreased by stimulation of the vagus nerve, clonidine significantly inhibited vagally induced heart rate decrease (negative chronotropic response) in dose dependent manner. This inhibitory effect of clonidine was virtually abolished by phentolamine, ${\alpha}_1-\;and\;{\alpha}_2-adrenoceptor$ antagonist, and partially antagonized by prazosin, ${\alpha}_1-adrenoceptor$ antagonist. On the other hand, when the heart rate was decreased by the infusion of bethanechol, a muscarinic parasympathetic stimulant, clonidine had no effect on the bethanechol-induced heart rate decrease. These results suggest that clonidine inhibits vagally induced negative chronotropic response by activation of presynaptic ${\alpha}-adrenoceptors$ located on the parasympathetic cholinergic nerve terminal in the heart and this effect of clonidine is more related to ${\alpha}_2-adrenoceptors$ than ${\alpha}_1-adrenoceptors$.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.27-28
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• 2019

Recently, a bed company detected a radon more than Red Politics and became a hot topic of conversation. This has led to increased interest in radon, and a number of free-of-charge bodies have also been established to recognize the dangers of radon. In addition, the Korean Institute of Geological and Resource Research is planning to assist the installation of radon alarm systems in 10,000 households nationwide, free of charge. Since radon is a colorless, odorless and tasteless gas that causes lung cancer, it aims to reduce lung cancer incidence by absorbing radon using bamboo activated carbon as a way to reduce it. Due to the use of bamboo activated carbon, radon concentration per hour tends to decrease as substitution rate increases, and table flow tends to decrease as substitution rate increases. Through this experiment, 30% of the replacement rate of bamboo activated carbon is judged to be the most suitable replacement rate.

• 대한기계학회논문집B
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• 제32권10호
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• pp.776-783
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• 2008

The object of this paper is to study on the thermal performance of a micro channel water block for computer CPU cooling. The effects of liquid flow rate, micro channel width and height on the thermal performances of water block are investigated experimentally. The water block was fabricated Al and machined with a micro milling. The water block consisted of rectangular micro channels 0.5 to 0.9 mm width and 1.5 to 4.5 mm height. The experiments were conducted using deionized water, over a liquid flow rate ranging from 0.2 to 2.0 kg/min. The base temperature and thermal resistance decrease with increasing of liquid flow rate. The increase of a channel height is more effective on the thermal resistance than the decrease of a channel width. At the flow rate of 0.7 kg/min, input power of 100 W, the base temperature and thermal resistance of sample 6 is $33^{\circ}C$ and $0.13\;^{\circ}C/W$ respectively.

• Journal of Plant Biology
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• 제25권3호
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• pp.113-121
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• 1982

The effects of 6 biocides on the growth of Chlamydomonas reinhardii in pure culture were studied. For the batch culture assay of biocides, the growth rate in control tubes should be compared with in the test tubes and the effective concentration calculated on the basis of the percent decrease in growth rate at the different toxicant concentration. The concentrations at which 50% decrease in growth rate was observed are $40{\mu}g$/l for butachlor and $350{\mu}g$/l for alachlor in herbicide, $900{\mu}g$/l for phenazine-5-oxide and $3,400{\mu}g$/l for isoprothiolane in fungicide, and $3,330{\mu}g$/l for fenthion and $332,500{\mu}g$/l for trichlorfon in insecticide. The inhibitory effect on the growth of Chlamydomonas reinhardii by the treatment of various biocide concentrations was decreased in order of herbicide>fungicide>insecticide. Chlorophyll and carotenoid content per cell were increased, whereas chlorophyll a/b ratio was hardly affected by biocides. The effects of biocides on pigment content were also decreased in order of herbicide>fungicide>insecticide, which suggested the relationship between the effect of biocides on the pigment content and inhibition of growth rate.

• 한국전기전자재료학회논문지
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• 제19권6호
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• pp.507-511
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• 2006

We investigated accelerated soft error rate (ASER) in static random access memory (SRAM) cells of thin film transistor (TFT) type. The effects on ASER by cell density, buried nwell structure, operational voltage, and polysilicon-2 layer thickness were examined. The increase in the operational voltage, and the decrease in the density of SRAM cells, respectively, resulted in the decrease of ASER values. The SRAM chips with buried nwell showed lower ASER than those with normal well structure did. The ASER decreased as the test distance from alpha source to the sample increased from $7{\mu}m\;to\;15{\mu}m$. As the polysilicon-2 thickness increased up to $1000\;{\AA}$, the ASER decreased exponentially. In conclusion, the best condition for low soft error rate, which is essential to obtain highly reliable SRAM device, is to apply the buried nwell structure scheme and to fabricate thin film transistors with the thick polysilicon-2 layer

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제33회 춘계학술대회 개최
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• pp.346-353
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• 2001

Zirconia powder containing 3 mol% yttria(3Y-PSZ) with and with out Fe$_2$O$_3$ addition was coated on tile cast iron substrate by plasma spraying method. The erosion experiments were performed at temperatures from $25^{\circ}C$ to $600^{\circ}C$. A gas blast type erosion tester was used to examine erosion behavior of the specimens. The results of 3Y-PSZ coatings showed that tile erosion rate had maximum value at 40$0^{\circ}C$. It coincided with tile results of phase transformation tetragonal phase to monoclinic phase caused by low temperature thermal degradation. The tensile stress relaxation and the micro-hardness improvement significantly influenced on the erosion rate at $600^{\circ}C$. In the case of Fe$_2$O$_3$ added 3Y-PSZ coatings, the erosion rate of tested at $25^{\circ}C$ showed maximum value at 5.0 mol% Fe$_2$O$_3$ added coating. This tendency is caused by the improvement of mechanical properties and the tensile residual stress. The erosion rate at 200'c and 400'L showed significantly decrease by Fe203 addition. This decrease is believed to be the stabilization of the tetragonal phase and the increase of micro-hardness.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.10-10
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• 2022

The concern about food security is rising as the unstable situation of food supply and demand due to the Covid-19 pandemic, climate change, and turbulent political situation. Korea's global food security index (GFSI), analyzed by the Economist Group, is considered good, but the level continuously decreases in comparing food security levels by country. In particular, Korea is highly dependent on food imports, and food and grain self-sufficiency rates continuously decrease. Therefore, increasing those rates to strengthen food security is urgent. Among the major grains, the self-sufficiency of wheat, com, and soybeans, except rice, is relatively low. Unlike the decrease in the annual rice consumption, the annual wheat consumption has been continuously maintained or increased, which is required public-private efforts to increase the self-sufficiency rate of wheat. Applying the government's policies implemented to increase the self-sufficiency rate of rice in the past will help increase the self-sufficiency rate of wheat. In other words, expanding wheat production and infrastructure, stabilizing supply and demand, and establishing a distribution system can be applied. However, the processing capability of wheat and rice is different, which is necessary to improve wheat quality and processing technology to produce consumer-preferred wheat-based products. The wheat and flour quality can be improved through breeding, cultivation, post-harvest management, and milling. In addition, research on formulation, processes, packaging, and storage to improve the quality of wheat-based products should be done continuously. Overall, food security could be strengthened by expanding wheat production and consumption, improving wheat quality, and increasing wheat self-sufficiency.

• 대한지역사회영양학회지
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• 제15권1호
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• pp.15-26
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• 2010

The purpose of this study was to compare nutrient intakes and blood lipids of middle-aged women according to the obesity index by %Fat. Subjects were assigned to one of the following groups based on percentage of body fat (%Fat): normal weight (18% ~ < 28%), overweight (28% ~ < 33%) and obesity (over 33%). Nutrient intakes were evaluated based on questionnaires of 24 hours recall method and blood lipids were analyzed by blood analyzer. The results were as follows. 1) Nutrient intakes were that carbohydrates and fat intakes in obesity group were higher than normal and overweight group but the difference was not significant, and protein intake rate was similar all groups. The intake rate of calcium was higher in normal group than obesity group (p < 0.05), and obesity group ingested under dietary reference intakes. The intake rate of iron was higher in obesity group than normal group (p < 0.05). 2) TG, TC, VLDL and TC/HDL in obesity group were higher than normal group (p < 0.001). The attack rate of coronary heart disease in obesity group is higher than normal group (p < 0.01), LDL, blood glucose and blood pressure in obesity group were higher than normal group (p < 0.01), and HDL was a little higher in normal group than obesity group, but the difference was not significant. 3) The correlation of anthropometric measurements, blood glucose, blood lipid, and blood pressure had significant results. Weight was associated positive level with blood glucose, blood lipid and blood pressure. Waist and WHR were associated positive level with blood glucose and blood lipid but weren't associated with blood pressure. BMI was associated positive level with blood glucose, blood lipid and blood pressure, %Fat was associated positive level with blood lipid and blood pressure, but wasn't associated with blood glucose. These results suggest that the decrease of waist on blood glucose control is better than decrease of % Fat and BMI, the decrease of %Fat and BMI on blood pressure control is better than decrease of waist, and the decrease of %Fat on blood lipid control is better than waist and BMI. The nutritional education for obesity treatment must perform to analyze the blood and assess the obesity degree by %Fat, waist and BMI before nutritional education, so the obesity treatment will be effectively.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.1142-1148
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• 2006

The floating ring seal which is used in the high pressure turbo pump is frequently used in the oxidizer pump and the fuel pump of the turbo pump of the liquid propulsion rocket, because it is able to minimize clearance to decrease the leakage flow rate. But, floating ring seal has a tendency to increase the force which caused instability of system as the eccentricity ratio increases. In this paper, we devised design of floating ring seal which decrease contact area between floating and supporting ring. Modified floating ring seal has a tendency to decrease the eccentricity ratio compare with original floating ring seal. The whirl frequency ratio which is able to distinguish stability of system decrease compare with original floating ring seal

• Safety and Health at Work
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• 제2권1호
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• pp.52-56
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• 2011

Objectives: The occupational accident rate was officially reported to be 0.77 per 100 workers in 2001 and 0.70 in 2009. The stagnant decrease in accident rate raises a question about the effectiveness of prevention activity because there have been active prevention efforts in the past 10 years. It is also necessary to know the exact status of occupational injuries to direct a prevention strategy. Methods: The author re-analyzed occupational injury statistics to find the reason for stagnant decreases in occupational injuries. Compensated occupational injuries cases were used to calculate fatal and non-fatal injury rates. Injuries from commuting accidents and sports activities were excluded as well as occupational diseases. The number of workers was adjusted to that of full time equivalent employees. Results: The fatal injury rate excluding injuries associated with commuting accidents, sports activities, and occupational diseases decreased from 12.59 in 2001 to 8.20 in 2009. In 2007, 67.5% of accidents that involved being caught in objects, which are mostly caused by machines and equipment, occurred in the manufacturing industry; this type of incident has decreased since 2001. The fatal and non-fatal injury rates in the manufacturing industry have continuously decreased while the rates in the service industry have not changed from 2001 to 2009. Non-fatal injuries might not be reported in many cases. The number of insured workers was underestimated as long working hours were not adjusted for in the reporting system. Conclusion: The occupational fatal injury rate has decreased and the non-fatal injury rate might have decreased during the last 10 years, although the statistics show stagnancy. The decrease of the injury rate was countervailed by various factors. Hence, the current accident rate does not reflect the actual situation of accidents in Korea. Korea needs to develop an improved system to more accurately calculate occupational fatal and non-fatal injury rates.