• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.75-82
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• 2002

The effects of intake mixture temperature on performance and exhaust emissions under four kinds of engine loads were experimentally investigated by using a four-cycle four-cylinder, swirl chamber type, water-cooled diesel engine with scrubber EGR system operating at three kinds of engine speeds. The purpose of this study is to develop the scrubber exhaust gas recirculation(EGR) control system for reducing $NO_x$ and soot emissions simultaneously in diesel engines. The EGR system is used to reduce NOx emissions. And a novel diesel soot-removal device with a cylinder-type scrubber which has five water injection nozzles is specially designed and manufactured to reduce soot contents in the recirculated exhaust gas to the intake system of the engine. The influences of cooled EGR and water injection, however, would be included within those of scrubber EGR system. In order to study the effect of intake mixture temperature, a intake mixture heating device which has five heating coils is made of a steel drum. It is found that the specific fuel consumption rate is considerably elevated by the increase of intake mixture temperature, and that NOx emissions are markedly decreased as EGR rates are increased and intake mixture temperature is dropped, while soot emissions are increased with increasing EGR rates and intake mixture temperature.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.2
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• pp.315-331
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• 2004

The effects of intake mixture temperature on performance and exhaust emissions under four kinds of engine loads were experimentally investigated by using a four-cycle. four-cylinder. swirl chamber type. water-cooled diesel engine with scrubber EGR system operating at three kinds of engine speeds. The purpose of this study is to develop the scrubber exhaust gas Recirculation (EGR) control system for reducing $\textrm{NO}_{x}$ and soot emissions simultaneously in diesel engines. The EGR system is used to reduce $\textrm{NO}_{x}$ emissions. And a novel diesel soot-removal device of cylinder-type scrubber with five water injection nozzles is specially designed and manufactured to reduce soot contents in the recirculated exhaust gas to the intake system of the engine. The influences of cooled EGR and water injection. however. would be included within those of scrubber EGR system. In order to survey the effects of cooled EGR and moisture on $\textrm{NO}_{x}$ and soot emissions. the intake mixtures of fresh air and recirculated exhaust gas are heated up using a heater with five heating coils equipped in a steel drum. It is found that intake and exhaust oxygen concentrations are decreased, especially at higher loads. as EGR rate and intake mixture temperature are increased at the same conditions of engine speed and load. and that $\textrm{NO}_{x}$ emissions are decreased. while soot emissions are increased owing to the decrease in intake and exhaust oxygen concentrations and the increase in equivalence ratio. Thus ond can conclude that $\textrm{NO}_{x}$ and soot emissions are considerably influenced by the cooled EGR.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2002.11a
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• pp.100-111
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• 2002

The effects of intake mixture temperature on performance and exhaust emissions under four kinds of engine loads were experimentally investigated by using a four-cycle, four-cylinder, swirl chamber type, water-cooled diesel engine with scrubber EGR system operating at three kinds of engine speeds. The purpose of this study is to develop the scrubber exhaust gas recirculation(EGR) control system for reducing $NO_x$ and soot emissions simultaneously in diesel engines. The EGR system is used to reduce $NO_x$ emissions. And a novel diesel soot-removal device of cylinder-type scrubber with five water injection nozzles is specially designed and manufactured to reduce soot contents in the recirculated exhaust gas to the intake system of the engine. The influences of cooled EGR and water injection, however, would be included within those of scrubber EGR system. In order to survey the effect of intake mixture temperature on performance and exhaust emissions, the intake mixtures of fresh air and recirculated exhaust gas are heated by a heating device with five heating coils made of a steel drum. It is found that the specific fuel consumption rate is considerably elevated by the increase of intake mixture temperature, and that $NO_x$ emissions are markedly decreased as EGR rates are increased and intake mixture temperature is dropped, while soot emissions are increased with increasing EGR rates and intake mixture temperature. Thus one can conclude that the performance and exhaust emissions are considerably influenced by the cooled EGR.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.506-514
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• 2014

Recently the interest about the vortex intakes are rapidly increased because of its performance to drain a plenty of collected storm water at a time. The tangential intake a kind of vortex intakes is very applicable because this type is very simple and little against other types, but it has a big weakness that the vortex flow is not been rarely created below the design discharge. In this study, the characteristics of a tangential intake and two kinds of a newly suggested compound section type intake are analyzed by the 3D numerical modeling based on theories about the control shift and free drainage condition. The analysis focused on the flow condition, flow surface formation, depth-discharge relation, area ratio of air core. Based on this study, the mild-sloped compound section type intake is the optimal, but steep-sloped compound section type is also the optional for the small design discharge.

• Nutrition Research and Practice
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• v.5 no.1
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• pp.34-39
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• 2011

The purpose of this study was to assess vitamin $B_6$ intake and status in Korean patients with newly diagnosed type 2 diabetes. Sixty-four patients with newly diagnosed type 2 diabetes and 8-11% glycated hemoglobin (A1C), along with 28 age-matched non-diabetic subjects, participated. Dietary vitamin $B_6$ intake was estimated by the 24 hour recall method and plasma pyridoxal 5'-phosphate (PLP) was measured. There was a significant difference in daily total calorie intake between the diabetic and non-diabetic groups ($1,917{\pm}376$ vs $2,093{\pm}311\;kcal$). There were no differences in intake of total vitamin $B_6$ ($2.51{\pm}0.91$ vs $2.53{\pm}0.81\;mg/d$) or vitamin $B_6$/1,000 kcal ($1.31{\pm}0.42$ vs $1.20{\pm}0.32\;mg$) between the diabetic and non-diabetic groups, and I intakes of total vitamin $B_6$ were above the Korean RDA in both groups ($180.0{\pm}57.9$ vs $179.0{\pm}65.4$). There was a higher percentage of diabetic subjects whose plasma PLP concentration was < 30 nmol/L compared to non-diabetic group. Plasma PLP levels tended to be lower in the diabetic subjects than in the non-diabetic subjects, although the difference was not statistically significant due to a large standard deviation ($80.0{\pm}61.2\;nmol/L$ vs $68.2{\pm}38.5\;nmol/L$). Nevertheless, plasma PLP levels should be monitored in pre-diabetic patients with diabetic risk factors as well as in newly diagnosed diabetic patients for long-term management of diabetes, even though this factor is not a major risk factor that contributes to the development of degenerative complications in certain patients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.934-941
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• 1999

This study was performed to investigate the effect of family type on the nutrient intake and nutritional status in elderly women. Blood samples and anthropometric data of elderly women aged from 60 to 78 years were collected in 1996, who visited a health examination center in Seoul to screen their health status. They were divided into two groups by their family type, one was extended family(extended family elderly, n=37) and the other was independently living(independently living, n=29). Nutrients intake was measured by interview using a simplified questionaire. Albumin, cholesterol, triglyceride(TG), hemoglobin (Hb), hematocrit, Ca, Mg, and alkaline phosphatase activity of serum were analyzed. Intakes of energy, protein, carbohydrate, Fe, vitamin A, niacin, thiamin, riboflavin, and vitamin C were not different between the two groups. However, fat and Ca intakes were higher(p<0.05) in extended family elderly than indepen dently living elderly. There are no significant difference in hematocrit value and serum concentrations of Hb, TG, and Ca. Serum Mg and cholesterol levels tended to be higher in extended family elderly. However, serum albumin level was lower(p<0.05) in extended family elderly. These results show that the indepen dently living elderly women had intakes of daily energy, fat and Ca compared to the extended family elderly. Therefore, the nutritional education for the independently living elderly will be focused on the health risk resulted from less intakes of Ca and total energy.

• Transactions of the Korean Society of Automotive Engineers
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• v.1 no.2
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• pp.27-33
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• 1993

Using the solenoid driven gas injection valve, Hydrogen fuel supply system was made. It was attached to a single cylinder research engine and intake port injection type hydrogen fueled S.I. engine was constructed. Engine performance, emission characteristics, and abnormal combustion were studied through the engine test performed with the variations of fuel-air equivalence ratio and spark timing. Compared with gasoline, hydrogen burns so fast that cylinder peak pressure and temperature are higher and NO is emitted more at full load condition. IN the case of intake port injection type engine, COVimep becomes lower due to the well-mixing of air and fuel, and engine output is lower owing to the low volumetric efficiency. As fuel-air equivalence ratio goes up, the combustion speed increases, and COVimep decreases. NO emission peaks slightly lean of stoichiometric. As spark timing advances and fuel-air equivalence ratio goes up, the cylinder peak pressure and temperature become higher, so abnormal combustions take place easily.

• Nuclear Engineering and Technology
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• v.42 no.1
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• pp.109-114
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• 2010

Bioassay data analysis software (BiDAS-2007) has been developed by KAERI, which adds several new functions to its previous version. New functions of the BiDAS-2007 computer code enable the user not only to do a simultaneous analysis by using two or more types of bioassay for the best internal dose evaluation, but also to do a continual internal dose evaluation from a change of the internal exposure conditions such as an intake type (acute, chronic), an intake pathway (inhalation, ingestion), an absorption type (Type F, M, S), and a particle size (AMAD, activity median aerodynamic diameter), and also to estimate the intakes in various conditions of an internal exposure at a time. The values calculated by the BiDAS-2007 code are consistent and in good agreement with those values by IMIE-2004 code by Berkovski and IMBA code by Birchall. The BiDAS-2007 computer code is very useful and user-friendly to estimate the radionuclide intakes and committed effective doses of a radiation worker.

• The KSFM Journal of Fluid Machinery
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• v.20 no.1
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• pp.74-80
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• 2017

Pump sump system or pumping stations are built to draw water from a source such as river and used for irrigation, thermal power plants etc. If pump sump is improperly shaped or sized, air entraining vortices or submerged vortices may develop. This may greatly affect pump operation if vortices grow to an appreciable extent. Moreover, the noise and vibration of the pump can be increased by the remaining of vortices in the pump flow passage. Therefore, the vortices in the pump flow passage have to be reduced for a good performance of pump sump station. In this study, the effect of pump intake leaning angle and flow rate on the pump sump internal flow has been investigated. There are three cases with different leaning angle. Moreover, a pipe type with elbow also has been studied. The flow rate with three classes of air entraining vortices has been examined and investigated by decreasing the water level. The result shows that the air entraining vortices easily occurs at the pump intake with large leaning angle. Moreover, the elbow type of the pump intake easily occurs air entraining vortices at the high flow rate (or velocity) in comparison to other pump intake type.

• Journal of the Korean Society of Food Culture
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• v.36 no.6
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• pp.583-594
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• 2021

This study examined the nutrient intake of Korean adults by considering the lunch type, categorized as home meals (HM), eating out (EO), and institutional meals (IM). Data was obtained from the 2019 Korea National Health and Nutrition Examination Survey (KNHANES). Totally, 3,786 adults (1,643 men, and 2,143 women) aged between 19-64 years were included in the study. Subjects with daily energy intake of less than 500 kcal or over 5,000 kcal, and those who skipped lunch, were excluded. The percentage of subjects in the HM, EO, and IM were 31.9, 53.6, and 14.4%, respectively. The daily energy intakes of the HM, EO, and IM groups were determined to be 2,185, 2,360, and 2,339 kcal, respectively, in men, and 1,622, 1,731, and 1,741 kcal, respectively, in women. Among the three groups, men in the EO group had more intake of fat, saturated fat, cholesterol, sodium, and riboflavin, and less dietary fiber, and whereas women consumed more fat and less dietary fiber and potassium. In the IM group, the men consumed more dietary fiber, potassium, and thiamine, whereas consumption of carbohydrate, unsaturated fatty acid, sodium, potassium, and thiamine was more in women. Energy contributions of carbohydrate, protein, and fat were all within the AMDR (acceptable macronutrient distribution ranges) for all lunch types, except for the percent of energy provided from saturated fat in EO (7.4% in men, and 8.2% in women). Our results indicate that the dietary habit of frequently eating out increases the fat intake, thereby resulting in increased health risks for adults. Thus, implementation of a nutritional education program to encourage balanced dietary habits is required to improve the nutritional status of individuals eating out.