• The Journal of the Acoustical Society of Korea
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• v.37 no.1
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• pp.31-38
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• 2018

Based on the measured data in the south western sea of Jeju Island during the SAVEX15(Shallow Water Acoustic Variability EXperiment 2015), the effect of internal waves on the PPD (Predictive Probability of Detection) of a sonar system was analyzed. The southern west sea of Jeju Island has complex flows due to internal waves and USC (Underwater Sound Channel). In this paper, sonar performance is predicted by probabilistic approach. The LFM (Linear Frequency Modulation) and MLS (Maximum Length Sequence) signals of 11 kHz - 31 kHz band of SAVEX15 data were processed to calculate the TL (Transmission Loss) and NL (Noise Level) at a distance of approximately 2.8 km from the source and the receiver. The PDF (Probability Density Function) of TL and NL is convoluted to obtain the PDF of the SE (Signal Excess) and the PPD according to the depth of the source and receiver is calculated. Analysis of the changes in the PPD over time when there are internal waves such as soliton packet and internal tide has confirmed that the PPD value is affected by different aspects.

• Journal of Life Science
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• v.23 no.12
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• pp.1509-1515
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• 2013

The term lipotoxicity has been used to describe how excess lipid accumulation leads to cellular dysfunction and death in non-adipose tissues, including skeletal muscle. While lipotoxicity has been found in cultured skeletal muscle cells with high-fat feeding, the consequences of lipotoxicity in vivo are still unknown, particularly in Type-I muscle, which is metabolically affected by lipotoxicity. The aim of this study was to investigate the effects of a high-fat diet on changes in the morphology and apoptotic protein expression of Type-I muscle loss in rats. The rats were fed either a high-fat diet or a normal diet for six weeks, and then lipid accumulation, inflammation response, and nucleus infiltration were measured, and PARP protein expression was cleaved by Oil Red O staining, H & E staining, and Western blot, respectively. Lipid accumulation, inflammation response, nucleus infiltration, and cleaved PARP protein expression were significantly (p<0.05) higher in the high-fat diet group than they were in the normal diet group. The weight of Type-I muscle tended to be lower in the high-fat diet group compared to the normal diet group, but the difference was not statistically significant. These results indicate that a high-fat diet triggers cell death in Type-I muscle via lipotoxicity, which suggests that a high-fat diet may be associated with sarcopenia.

• Journal of the Korean Institute of Gas
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• v.22 no.2
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• pp.59-66
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• 2018

Using hydrogen fuel is expected to be suitable as a reciprocating internal combustion engine with heightened interest in HALE(High Altitude Long Endurance) UAV(Unmanned Aerial Vehicle). Hydrogen is hightest energy density per mass so it can continue to charge for long periods of time and have positive part of the environmental effects. However, it is estimated that there is less research on hydrogen fuel engine currently applied, and many studies need to be done. Depending on the operation, there are factors that result in supercooling due to reduced radiation or reduce cooling performance due to low air density. Therefore, the experiment was to change the temperature of the cooling water and investigate the effect on engine combustions. The limitation of the stable operation range due to backfire is dominated by the excess air ratio rather than the effect of the cooling water temperature change. When the cooling water temperature increases, the volumetric efficiency decreases and the torque decreases. As the cooling water temperature decreases, the heat loss was increased and consequently the thermal efficiency was decreased.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.239-244
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• 2000

Synthesis and high temperature phase stability of $_{1+x}$ Co$_{y}$ Mn$_{2-y}$ $O_4$(0$\leq$x$\leq$0.2,y=0,1/9,1/6) spinel, both the excess lithium and cobalt added, have been studied. The spinel was prepared by oxalate precipitation method as the wet chemical process. Oxalate derived spinel was synthesized by heating of precipitates at temperature lower than $600^{\circ}C$. As a result of the TG-DTA and XRD analysis of prepared and quenched powders, it was found that reversible phase transitions started at temperatures $T_1$, $T_2$및 $T_{2'}$. The transitions involved weight (oxygen) loss and gain during heating and cooling. The effects of Li excess and Co doping on the spinel lattice constant, phase stability and transition temperatures of the prepared powders are investigated. This study would provide important data for determining the spinel preparation process such as synthesis temperature and cooling speed.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.725-731
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• 2008

The principal objective of this study was to assess the effects of low-calorie diets(LCD) for 8 weeks of medical nutrition therapy in individuals with BMI in excess of $23\;kg/m^2$. 41 over-weight or obese individuals (male=14, female=27, age $28.6{\pm}8.9\;yrs$), none of whom were diagnosed with a medical disease, were administered MNT 4 times over the study period. Approximately $1,100{\sim}1,300\;kcal/day$ were prescribed by a dietitian, via individualized counseling. Anthropometric parameters, daily nutrient intake, and blood levels of leptin, insulin, and lipid profiles were measured prior to and after the 8 weeks of the intervention period. We noted significant reductions in body weight, body mass index (BMI), fat mass (FM), visceral adipose tissue (VAT), abdominal skin-fold thickness, and waist circumference in both men and women. The mean body weight losses in men and women were $3.2{\pm}0.6\;kg$/8 weeks and $2.8{\pm}0.6\;kg$/8 weeks, respectively. However, the % of lean body mass (LBM) in men and women was shown to increase significantly (p<0.05). The daily intake of calorie, fat, protein, vitamin E, folate, and iron were significantly reduced during the LCD period. Blood levels of lipids and glucose were in normal range, and evidenced no changes after LCD. However, the serum levels of leptin in female subjects were significantly reduced (p<0.00l) from $8.9{\pm}4.8\;ng/mL$ to $6.9{\pm}4.8\;ng/mL$. In conclusion, 8 weeks of LCD with individualized counseling by a dietitian effectively reduced body fat and visceral fat in both men and women with BMI in excess of $23\;kg/m^2$.

• The Korean Journal of Blood Transfusion
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• v.29 no.3
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• pp.229-239
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• 2018

The circulatory system is closely related to the inter-relationship between the anatomy of the heart and blood vessels, and the fluid dynamic properties of blood. The physical properties of blood, which affect blood flow, are called hemorheologic factors. Hemorheologic factors, such as blood viscosity and erythrocyte aggregation, are influenced mainly by hematocrit. A higher hematocrit level results in an increase in blood viscosity, erythrocyte aggregation, which impedes the circulation itself, and tissue oxygenation. An excess of serum ferritin causes injury to vascular endothelial cells and erythrocytes via oxygen free radicals. In addition, an excess of blood can aggravatee the adverse effects of the hemorheologic parameters and induce atherogenesis, microcirculatory disturbances, and major cardiovascular events. A preventive and therapeutic approach with a phlebotomy or blood donation has been stimulated by the knowledge that blood loss, such as regular donations, is associated with significant decreases in key hemorheologic variables, including blood viscosity, erythrocyte aggregation, hematocrit, and fibrinogen. Major cardiovascular events have been improved in regular blood donors by improving blood flow and microcirculation by decreasing the level of oxidative stress, improving the hemorheologic parameters, and reducing the serum ferritin level. Confirmation of the positive preventive and therapeutic effects of blood donations on cardiovascular disease by a well-designed and well-controlled Cohort study may be good news to patients with cardiovascular disease or at risk of these diseases, as well as patients who require a transfusion.

• Journal of Biosystems Engineering
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• v.5 no.1
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• pp.1-14
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• 1980

Threshing operation may be one of the most important processes in the paddy post-production system as far as the grain loss and labor requirement are concerned . head-feeding type threshers commercially available now in Korea originally were developed for threshing dry paddy in the range of 15 to 17 % in wet basis. However, threshing wet-paddy with the grain moisture content above 20 % has been strongly recommended, especially for new high-yielding Indica -type varieties ; (1) to reduce high grain loss incurred due to the handling operations, and (2) to prevent the quantitative and qualitative loss of milled -rice when unthreshed grains are rewetted due to the rainfall. The objective of this study were to investigate the adaptability of both a head-feeding type thresher and a throw-in type thresher to wet-paddy , and to find out the possiblilities of improving the components of these threshers threshing. Four varieties, Suweon 264 and Milyang 24 as Tongil sister line varieties, minehikari and Jinhueng as Japonica-type varieties, were used at the different levels of the moisture content of grains. Both the feed rate and the cylinder speed were varied for each material and each machine. The thresher output quality , composition of tailing return, and separating loss were analyzed from the sampels taken at each treatment. A separate experiment for measurement opf the power requirement of the head-feeding type thresher was also performed. The results are summarized as follows : 1. There was a difference in the thresher output quality between rice varieties. In case of wet-paddy threshing at 550 rpm , grains with branchlet and torn heads for the Suweon 264 were 12 % and 7 % of the total output in weight, respectively, and for the Minehikari 4.5 % and 2 % respectively. In case of dry paddy threshing , those for the Suweon 264 were 8 % and 5% , and for the Minehikari 4% and 1% respectively. However, those for the Milyang 23 , which is highly susceptable to shattering, were much lower with 1 % and 0.5% respectively, regardless of the moisture content of the paddy. Therefore, it is desirable to breed rice varieties of the same physical properties as well as to improve a thresher adaptable to all the varieties. Torn heads, which increased with the moisture content of rall the varieties except the Milyang 23 , decreased as the cylinder speed increased, but grains with branchlet didnt decrease. The damaged kernels increased with the cylinder speed. 3. The thresher output quality was not affected much by the feed rate. But grains with branchlet and torn heads increased slightly with the feed rate for the head-feeding type thresher since higher resistance lowered at the cylinder speed. 4. In order to reduce grains with branchlet and torn heads in wet-paddy threshing , it is desirable to improve the head-feeding type thresher by developing a new type of cylinder which to not give excess impact on kernels or a concave which has differenct sizes of holes at different locations along the cylinder. 5. For the head-feeding type thresher, there was a difference in separating loss between the varieties. At the cylinder speed of 600 rpm the separating losses for the Minehikari and the Suweon 264 were 1.2% and 0.6% respectively. The separating loss of the head-feeding type thresher was not affected by the moisture content of paddy while that of the Mini-aged thresher increased with the moisture content. 6. From the analysis of the tailings return , to appeared that the tailings return mechanism didn't function properly because lots of single grains and rubbishes were unnecessarily returned. 7. Adding a vibrating sieve to the head-feeding type thresher could increase the efficiency of separation. Consequently , the tailing return mechanism would function properly since unnecessary return could be educed greatly. 8. The power required for the head-feeding type thresher was not affected by the moisture content of paddy, but the average power increased linearly with the feed rate. The power also increased with the cylinder speed.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.576-581
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• 2014

Sodium chloride is an important ingredient added to most of foods which contributes to flavor enhancement and food preservation but excess intake of sodium chloride may also cause various diseases such as heart diseases, osteoporosis and so on. Therefore, this study was carried out to investigate the effect of monosodium glutamate (MSG) as a salty flavor enhancer on the quality and sensorial properties of the NaCl/MSG complex and actual food system. For characterizing the spray-dried NaCl/MSG complex, surface dimension, morphology, rheology, and saltiness intensity were estimated by increasing MSG (0-2.0%) levels at a fixed NaCl concentration (2.0%). MSG levels had no effect of the characteristics of the NaCl/MSG complex, although the addition of MSG increased the surface dimension of the NaCl/MSG complex significantly (p<0.05). Furthermore, the effect of MSG on enhancing the salty flavor was not observed in the solution of the NaCl/MSG complex. In the case of an actual food system, model meat products (pork patties) were prepared by replacing NaCl with MSG. MSG enhanced the salty flavor, thereby increasing overall acceptability of pork patties. Replacement of NaCl with MSG (<1.0%) did not result in negative sensorial properties of pork patties, although quality deterioration such as high cooking loss was found. Nevertheless, MSG had a potential application in meat product formulation as a salty flavor enhancer or a partial NaCl replacer when meat products were supplemented with binding agents.

• Journal of the Korean Dietetic Association
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• v.11 no.2
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• pp.147-158
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• 2005

The objectives of this study were to conduct preliminary research to investigate full course meals in Korean style restaurants in order: i) to analyze the nutrient contents of full course meals per servings, and ⅱ) by analyzing the above, to examine the amount and the quality of the foods served in the full course meals by Korean style restaurants in Changwon. A total of 20 restaurants in Changwon participated in this study, and two investigators visited there, consumed and investigated it. A key finding was that restaurant patrons tended to overconsume nutrients as compared to the Korean Recommended Daily Allowance(RDA), and restaurants generated large amounts of food wastes due to the excess food served. Other findings were as follows: 1) 1,821.2Kcal were served, 1,052.6Kcal were consumed and 768.6Kcal which is equivalent to 1/3RDA were thrown away on average. 2) The average carbohydrate:protein:fat(CPF) ratio of caloric nutrients was 42:27:31. 3) The correlation between the consumed and unconsumed calories was r=0.661 and the correlation between served and unconsumed calories was r=0.819. Both consumed and unconsumed calories were closely related to the served calories. 4) The result of the research showed that mean INQ in most nutrients was higher than 1.0, especially INQ in unconsumed food is mostly higher than INQ in provided and consumed food. 5) The unconsumed food and the meal prices were closely correlated in terms of price loss. These findings indicate the Korean style full course meals consisted of a high-protein, high-fat and high-caloric intake, which is similar to a westernized caloric nutrient pattern. They should also be strongly encouraged to play an active role in improving their customers’ nutritional status, as well as reducing the restaurants wastage of food. Lastly, further research should be conducted to improve the quality of the menus in Korean restaurants.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.3
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• pp.58-68
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• 1988

Most of the Korean watersheds are mountaineous and consist of various soil types and land uses And seldom watersheds are found to have long term hydrologic records. The SNUA, a hydrologic watershed model was developed to meet the unique characteristics of Korean watershed and simulate the storm hydrographs from a small mountaineous watershed. Also the applicability of the model was tested by comparing the simulated storm hydrographs and the observed from Dochuk watershed, Gwangjugun, Kyunggido The conclusions obtained in this study could be summarized as follows ; 1. The model includes the simulation of interception, evaporation and infiltration for land surface hydrologic cycle on the single storm basis and the flow routing features for both overland and channel systems. 2. Net rainfall is estimated from the continuous computation of water balance at the surface of interception storage accounting for the rainfall intensities and the evaporation losses at each time step. 3. Excess rainfall is calculated by the abstraction of infiltration loss estimated by the Green and Ainpt Model from the net rainfall. 4. A momentum equation in the form of kinematic wave representation is solved by the finite differential method to obtain the runoff rate at the exit of the watershed. 5. The developed SNUA Model is a type of distributed and event model that considers the spatial distribution of the watershed parameters and simulates the hydrograph on a single storm basis. 6. The results of verification test show that the simulated peak flows agree with the observed in the occurence time but have relative enors in the range of 5.4-40.6% in various flow rates and also show that the simulated total runoff have 6.9-32% of relative errors against the observed. 7. To improve the applicability of the model, it was thought that more studies like the application test to the other watersheds of various types or the addition of the other hydrologk components describing subsurface storages are needed.