• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.654-661
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• 2000

Area of greenhouse increases rapidly up to 45,265ha by the year of 1998 in Korea. Hot air heater with light oil combustion is the most common heater for greenhouse heating in the winter season. However, exhaust gas heat discharged to atmosphere through chimney reaches up to 10~20% of total heat of the oil combusted in the furnace. In order to recapture the heat of this exhaust gas and to recycle for greenhouse heating, the heat pipe type exhaust heat recovery system was manufactured and tested in this experiment. The exhaust heat recovery system was made for space heating in the greenhouse. The system consisted of a heat exchanger made of heat pipes, ${\emptyset}15.88{\times}600mm$ located in the rectangular box of $600{\times}550{\times}330mm$, a blower and air ducts. The rectangular box was divided by two compartments where hot chamber exposed to exhaust gas in which heat pipes could pick up the heat of exhaust gas, and by evaporation of the heat transfer medium in the pipes it carries the heat to the cold compartment, then the blower moves the heat to greenhouse. The number of heat pipe was 60, calculated considering the heat exchange amount between flue gas and heat transfer capacity of heat pipe. The working fluid of heat pipe was acetone because acetone is known for its excellent heat transfer capacity. The system was attached to the exhaust gas path. According to the performance test it could recover 53,809 to 74,613kJ/hr depending on the inlet air temperature of 12 to $-12^{circ}C$ respectively when air flow rate $1,100\textrm{m}^3/hr$. The exhaust gas temperature left the heat exchanger dropped to $100^{circ}C$ from $270^{circ}C$ by the heat exchange between the air and the flue gas, the temperature difference was collected by the air and the warm air temperature was about $60^{circ}C$ at the air flow rate of $1,100\textrm{m}^3/hr$. This heat pipe type exhaust heat recovery system can reduce fuel cost by 10% annually according to the economic analysis.

• Journal of the Korean Society for Nondestructive Testing
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• v.14 no.2
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• pp.122-131
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• 1994

Journal bearings in the rotating machineries are vulnerable to the contamination or the insufficient supply of lubricating oil, which is likely to be the cause of unexpected shutdown or malfunction of these systems. Various destructive and nondestructive testing methods had been used for the reduction of maintenance cost and the operational safety problems due to the accidents related to bearing damages. In this experimental approach, acoustic emission monitoring is employed to the detection of incipient failure caused by intervention of foreign particles most probable in the journal bearing systems. Experimental schedules for the intervention of foreign particles was composed to be more quantitative and systematic than last study in consideration of minimum oil film thickness and particle size. The experiment was conducted under such designed conditions as inserting alumina particles to the lubrication layer in the simulated journal bearing system. Several parameters such as AE rms level, waveform, AE energy distribution and other AE event parameters are used for analysis and characterization of damage source. The results showed that the history of damage was well correlated with the changes of AE rms level and the type of damage source signal can be verified using other informations such as waveform, distributions of AE parameters etc.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.95-104
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• 2013

This research was performed to test the effects of oleic acid for the management of greenhouse whiteflies and tobacco whiteflies. Tobacco whiteflies, especially, are the vectors of tomato yellow leaf curl virus on tomato plants. Whiteflies are not only the vectors of various viruses but also the major insect pests that cause direct damages through sucking and induce sooty mold with their sweet dew on tomato plants. There are many eco-friendly management measures including the use of yellow sticky trap and natural enemies such as Eretmocerus eremicus and Amblyseius swirskii. However, these management measures have difficulties to implement in the greenhouse. Therefore, in this research, oleic acid was tested for its effect on the management of whiteflies at various concentrations of 1,000ppm, 2,000ppm, or 4,000ppm. As a result, treatments of 1,000ppm, 2,000ppm and 4,000ppm oleic acid showed the control value of 70%, 76% and 84%, respectively. In another test, treatments of 2,000ppm oleic acid, and control treatment of 1,5000ppm neem oil and 50ppm dinotefuran showed the control value of 82%, 75%, and 75%, respectively. Cost for one application of oleic acid and neem oil for 10a area would be 3,180 Won and 20,150 Won, respectively. As a result, it was assumed that the use of oleic acid would be a appropriate management measure.

• The Korean Nurse
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• v.29 no.3
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• pp.25-35
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• 1990

It is a fact that there are recent increasing trends or incidence of the colorectal carcinoma among other colorectal diseases. In such trend, the early detection remain to be most important by the air contrast barium enema and total colonofiberscopy. There are several ways to prepare the colon for barium enema and colonofiberscopy which include several agents. The mechanical cleansing have been used most frequently since Brown's method was adapted to be most perfect for colon deansing. The ideal laxatives and enema solutions were limited to adequate dose, it's effectiveness, patient's diet and bowel habit, minimal side effect, low cost and simple to perform. In order to compare the effectiveness of various cleansing solutions, six experimental methods were formed as shown; 1. normal saline enema, 2. castor oil with normal saline enema, 3. castor oil with soap suds enema, 4. magnesium citrate with normal saline, 5. magnesium citrate with soap suds enema and 6. ingestion of Golyetly solution. The authors have compared and determined the degree of cleanness by an experienced endoscopist. The total number of patients was 247, age distribution was $43{\pm}15$ years old, and sex distribution was 133 males and 114 females. The grade I and II represented no difficulties at performing the colonofiberscopy, but grade ill and N had some difficulties, even unable to perform the colonofiberscopy. The effectiveness the cleansing agents, represented with grade I and II was 95.9% (47/49) in method 6, 93.2%(54/58) in method 2, 83.3%(30/33) in method 3, 70.0%(28/10) in method 5, 66.7%(16/24) in method i, and 45.7%(18/40) in method 4. Method 2 and 6 were the most effective in normal bowel habit patients. In constipated patients, method 6 was the most effective and all method except method 11 were effective in diarrhea patients. The degrees of less mucosal irritation by various bowel cleansing method were in the order of method 6(100%), 1(100%), 5(74%), 2(69%). In subjective symptoms and cleansing groups, abdominal distension, pain, nausea and vomiting were complained, and that's subject symptoms were in the order of method 3(88.9%), 6 (79.6%), 1(75%), 5(72.5%), 2(72.4%), 4(67.5%). In conclusion, we believe that the Golytely of the mechanical cleansing solution for colonofiberscopy was the most effective, but others depended on the patient's condition und bowel habit.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.32-39
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• 1998

This study was performed to develop jumbo granules floated and spreaded on the water surface after application, having low production and formulation cost, and safe to environment for paddy herbicides and to establish the formulation recipe. The jumbo granules of azimsulfuron with molinate(0.075+7.5%) was formulated by KCl as water soluble carrier and paraffin oil as solvent to impose the floating and spreading force to granules. That showed 100% of total granules to be floated on and spreaded upto the water surface within 25 minutes after application. Change in carriers, surfactants and pH did not affected to improve the time-course degradation of azimsulfuron in jumbo granules, but salt formation of azimsulfuron added by 1.15M solution of NaOH a little. Addition of N-methyl acrylate and modification of formulation process affected decrease in degradation of azimsulfuron upto 1.2, 2.1, and 7.2% after 2, 6 and 12 weeks under storage at $40{\pm}2^{\circ}C$, respectively, which showed the establishment of formulation recipe of the jumbo granules.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.373-381
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• 2016

To investigate the influence of hand cream of domestic and foreign brands on the purchase tendency, a survey was conducted on hand cream application, purchase tendency, and perception of 105 women in a metropolitan area. Market research was then conducted to compare the hand cream cost, quantity, and total substance, and the hand creams were sorted according to high-price and low-price, and foreign brand and domestic brand, and a clinical demonstration was conducted by back-hand application on 17 recipients to analyze the moisture and skin oil differences and the moisture endurance. As a result, the percentage of subjects who perceived that the price and brand of hand cream affects the quality was higher than those who did not, and the hand cream prize per 1mg (g) varied as much as fourfold among the high-price and low-price, and among foreign and domestic brands. The result of the total substance comparison, glycerin the moisturizer and cetearyl alcohol the skin conditioner were included in all hand creams. As a result of the clinical demonstration, the difference in moisture and skin oil difference and moisture endurance between the high-price and low-price and foreign brand did not show a statistically significant difference. These results show that there are no relationships between skin moisture and sebeum of the brand. Therefore, considering that hand cream is a highly consumptive product that is used multiple times on a daily basis, these results might provide fundamental data that could contribute to the increase in hand cream product quality by determining the consumers' needs.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.56-61
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• 2009

Paradigm depending only on fossil fuel for building heat source is rapidly changing. Accelerating the change, as it has been known, is obligation for reducing green house gas coming from use of fossil fuel, i.e. reaction to United Nations Framework Convention on Climate Change. In addition, factors such as high oil price, unstable supply, weapon of petroleum and oil peak, by replacing fossil fuel, contributes to advance of environmental friendly renewable energy which can be continuously reusable. Therefore, current new energy policies, beyond enhancing effectiveness of heat using equipments, are to make best efforts for national competitiveness. Our country supports 11 areas for new renewable energy including sun light, solar heat and wind power. Among those areas, ocean thermal energy specifies tidal power generation using tide of sea, wave and temperature differences, wave power generation and thermal power generation. But heat use of heat source from sea water itself has been excluded as non-utilized energy. In the future, sea water heat source which has not been used so far will be required to be specified as new renewable energy. This research is to survey local heating system in Europe using sea water, central solar heating plants, seasonal thermal energy store and to analyze large scale central solar heating plants in German. Seasonal thermal energy store necessarily need to be equipped with large scale thermal energy store. Currently operating central solar heating system is a effective method which significantly enhances sharing rate of solar heat in a way that stores excessive heat generating in summer and then replenish insufficient heat for winter. Construction cost for this system is primarily dependent on large scale seasonal heat store and this high priced heat store merely plays its role once per year. Since our country is faced with 3 directional sea, active research and development for using sea water heat as cooling and heating heat source is required for seashore villages and building units. This research suggests how to utilize new energy in a way that stores cooling heat of sea water into seasonal thermal energy store when temperature of sea water is its lowest temperature in February based on West Sea and then uses it as cooling heat source when cooling is necessary. Since this method utilizes seasonal thermal energy store from existing central solar heating plant for heating and cooling purpose respectively twice per year maximizing energy efficiency by achieving 2 seasonal thermal energy store, active research and development is necessarily required for the future.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.2
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• pp.58-64
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• 2012

Due to the influence of global oil prices, industrial productivity, which oil consumption is high, was significantly reduced. AC type of high-strength PHC piles is being manufactured through twice the steam curing process and this have resulted in a significant rise for product's manufacturing costs. NAC way other types of file manufacturing process has the advantage of reducing manufacturing costs by a turn of the steam curing. Nevertheless, because the initial strength be poor than that of AC method, shipment is being after the curing period of approximately three days. In addition, the growth of the product enhance with curing period can not be avoided, as a result, cost of inventory is acting as the rise. Piles by the AC method is immediately shipped after curing, damaging problems does not occur when they are introduced to the field site (for example, pile on-site). In the case of NAC, however, at least after the curing period of three days and after expressing the strength of 80 MPa or more, they are shipped on the scene. Therefore, NAC type has problems as follows: (1) increase in moderate inventory holding costs with type and (2) breakage in the field due to lack of strength. In this study, for NAC-typed PHC files, mixing characteristics research for the strength development at 1 day equivalent to AC method were conducted and strength characteristics with changes of original materials were evaluated were also identified.

• Journal of Life Science
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• v.29 no.9
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• pp.1016-1022
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• 2019

Owing to increased interest in preventing obesity in an aging society, both men and women spend considerable amount of cost on obesity managements. In this study, we investigated the natural substances on anti-obesity activities in 3T3-L1 pre-adipocytes. Also, to improve anti-obesityeffects, research using 3T3-L1 pre-adipocytes cells is crucial. The anti-obesity effect of 70% ethanol extract from Torilis Japonica Decandolle on the differentiation of 3T3-L1 pre-adipocytes to adipocytes was investigated by suppressing adipocyte differentiation and lipid accumulation with Oil Red O assay, and western blot analysis. Compared to the control, 70% ethanol extract of Torilis Japonica Decandolle was significantly inhibited adipocyte differentiation and intracellular triglyceride (TG) level at a concentration of $100{\mu}g/ml$. To determine the mechanism of reduction in TG content, we determined the level of protein expression of obesity-related proteins, such as peroxisome-proliferatorsactivated-receptor-${\gamma}$ ($PPAR{\gamma}$) and CCAAT enhancer-binding-proteins-${\alpha}$ ($C/EBP{\alpha}$), and Acetyl-CoA carboxylase (ACC) phosphorylation. As a results, 70% ethanol extract of Torilis Japonica Decandolle significantly decreased protein expression of $PPAR{\gamma}$, $C/EBP{\alpha}$ and ACC phosphorylation. These results indicate that 70% ethanol extract of Torilis Japonica Decandolle is the most effective candidate for preventing obesity. However further studies will be needed to identify the active compounds that confer the anti-obesity activity of Torilis Japonica Decandolle.

• Analyses & Alternatives
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• v.5 no.2
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• pp.77-105
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• 2021

Natural gas consumption in Asia is growing at fast tempo because of various factors such as economic growth in the region, urbanization, coal-to-gas switch at power and industry sector. Due to geographical characteristics and lack of international pipeline connections between countries in the continent, majority of natural gas exported to Asian consumers is transported by tankers on the sea in the form of liquefied natural gas. As Asian market is the most lucrative market with the fastest demand growth, the competitions between LNG sellers for market share in Asian market are strengthening. The competitions accelerated, especially after the introduction of large volume of incremental supply into the market by new exporters from the U.S., Australia, and Russia. Cheniere Energy, the first exporter of liquefied natural gas (LNG) in the lower 48 states of U.S. has not adopted the traditional price formation mechanism and business model. Traditionally, prices of long-term LNG contracts have been indexed to the price of competing fuels, such as crude oil. The company adopted a pricing mechanism and business model based on a cost-plus system. Cheniere Energy opted for the safer and the risk-free pricing system, that annually guarantees a fixed amount of revenue to the seller. The company earns the same amount of money, regardless of natural gas price dynamics in the domestic and international market, but possibly with less revenue. However, by introducing and successfully implementing the safer and risk- free business model, Cheniere Energy, a company of a relatively smaller size in comparison with major oil and gas companies, became an example to other smaller-sized companies in the U.S. The company's business model demonstrated how to enter and operate LNG business amid increasing competitions among sellers in the U.S. and international market.