• Journal of the Korea Organic Resources Recycling Association
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• v.32 no.2
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• pp.37-48
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• 2024

Wastewater treatment plants (WWTPs) are obligated to reduce carbon emissions as a part of public sector greenhouse gas (GHG) emission reduction targets. However, Sewage Statistics(2022) shows that CO₂ emissions per wastewater treatment volumes have decreased by only 3.03 % compared to 2020, which is far from enough to meet the Nationally Determined Contribution (NDC) targets. This study aimed to find operational conditions of biological reactors that minimize total carbon footprint (CFP). Total CFP considers both direct emissions from biological processes and indirect emissions from energy consumption. A study was conducted using a computer simulation program which is called as EQPS for a 4-stage BNR WWTP. The results showed that total CFP was reduced by 10.97% compared to the design condition when the mixed liquor recirculation (MLR) was set to 100 % of the influent flow. The N₂O emission factor (EF) of the target WWTP was calculated to be 0.138-0.199 %, which is significantly lower than the IPCC default value of 1.6 %. This study proposes a method to minimize total CFP in WWTPs by optimizing biological reactor operation and emphasizes the need for further research on N₂O emission reduction.

• Nutrition Research and Practice
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• v.1 no.3
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• pp.231-236
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• 2007

Underreporting patterns by the level of obesity have not been fully assessed yet. The purpose of this study was to examine the differential underreporting patterns on cardiovascular risk factor, macronutrient, and food group intakes by the level of Body Mass Index (BMI). We analyzed cross-sectional baseline nutritional survey data from the population-based longitudinal study, the Healthy Women Study (HWS) cohort. Study subjects included 538 healthy premenopausal women participating in the HWS. Nutrient and food group intakes were assessed by the one-day 24-hour dietary recall and a semi-quantitative food frequency questionnaire, respectively. The ratio of reported energy intake (EI) to estimated basal metabolic rate (BMR) was used as a measure of relative energy reporting status and categorized into tertiles. Overweight group ($BMI{\geq}25kg/m^2$) had a higher ratio of EI to BMR (EI/BMR) than normal weight group ($BMI<25kg/m^2$). Normal weight and overweight groups showed similar patterns in cardiovascular risk factors, nutrient intake, and food group intake by the EI/BMR. Fat and saturated fat intakes as a nutrient density were positively associated with the EI/BMR. Proportion of women who reported higher consumption (${\geq}4\;times/wk$) of sugar/candy, cream and red meat groups was greater in higher tertiles of the EI/BMR in both BMI groups. Our findings suggest similar patterns of underreporting of cardiovascular risk factors, and macronutrient and food group intakes in both normal and overweight women.

• Journal of Electrical Engineering and Technology
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• v.13 no.5
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• pp.1917-1926
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• 2018

In view of the current state of the reserves of electric energy generated resources and the share of electric motors in electricity consumption, many researches and studies related to efficiency in electric motors are being made. The presented work is related to the Axial Flux Permanent Magnet Synchronous Motor (AF-PMSM), which has recently undergone significant work based on the development of magnet and motor technology. In this study, a novel AF-PMSM was designed analytically through Finite Element Method (FEM) which can be started by connecting to a line such as an asynchronous motor in a transient state and can operate with high efficiency and power factor after synchronization in steady state without the need for an expensive motor drive. According to the obtained FEM results, a design with an efficiency class of IE4 of 5.5 kW shaft power, a 4 poles motor was obtained. As a result, economic calculations indicate that the extra cost of the designed Line start AF-PMSM with respect to the asynchronous motor is rapidly compensated by energy saving due to a more efficient operation, especially constant speed operations. As a result of the analysis obtained, the targeted values are reached. For induction motors and radial flux permanent magnet synchronous motors, a good alternative motor that can operate with high efficiency and power factor has been obtained.

• Journal of Energy Engineering
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• v.11 no.2
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• pp.90-98
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• 2002

The effects of swirl and combustion parameters on the performance and emission in a turbo-charged D.I. diesel engine of the displacement 9.4L were studied experimentally in this paper. Generally the swirl in the combustion process of diesel engine promotes mixing of the injection fuel and the intake air. It is a major factor to improve the engine performance because the fuel consumption and NO$_{x}$ is trade-off according to the high temperature and high pressure of combustion gas in a turbocharged D.I. diesel engine, it's necessary to thinking over the intake and exhaust system, the design of combustion bowl and so on. In order to choose a turbocharger of appropriate capacity. As a result of steady flow test, when the swirl ratio is increased, the mean flow coefficient is decreased, whereas the gulf factor is increased. Also, through engine test its can be expected to meet performance and emissions by optimizing the main parameter's; the swirl ratio is 2.43, injection timing is BTDC 13$^{\circ}$ CA, compression ratio is 16, combustion bowl is re-entrant 5$^{\circ}$, nozzle hole diameter is $\Phi$0.28*6, turbocharger is GT40 model which are compressor A/R 0.58 and turbine A/R 1.19.

• Korean Journal of Community Nutrition
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• v.13 no.3
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• pp.418-425
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• 2008

The purpose of this study was to investigate correlations between bone mineral density (BMD) and dietary and non-dietary factors in female college students. The BMD of the subjects (n = 38) was measured using DEXA (Dual Energy X-ray Absorptiometry) at lumbar spine and three femoral sites including femoral neck, ward's triangle, and femoral trochanter. Three-day 24-hour dietary recall data were collected from each subject to assess consumption levels of nutrients and food groups. The mean (${\pm}SD$) values of age, age of menarche, height, weight, body mass index (BMI), waist-to-hip ratio (WHR), fat mass, and % body fat of the subjects were 21.34 (${\pm}1.73$) years, 13.1 (${\pm}1.2$) years, 161.3 (${\pm}5.0$) cm, 53.7 (${\pm}7.2$) kg, 20.6 (${\pm}2.6$) $kg/m^2$, 0.80 (${\pm}0.04$), 15.4 (${\pm}4.4$) kg, and 28.2 (${\pm}4.7$), respectively. The BMD values of lumbar spine, femoral neck, ward's triangle, and femoral trochanter as T-value were $1.150{\pm}0.13\;g/cm^2$, $0.932{\pm}0.11\;g/cm^2$, $0.850{\pm}0.13\;g/cm^2$, and $0.721{\pm}0.10\;g/cm^2$, respectively. The daily mean energy intake of the subjects was 1660.6 kcal. The intake levels of carbohydrate, calcium, iron, vitamin C, and folic acid were lower than the KDRIs, while those of fat, phosphorus, sodium, vitamin A, and vitamin $B_6$ were higher than the KDRIs. Significantly negative correlation were detected between consumption of fat and oils and the BMD of all sites measured (p < 0.05). Potato and starch intake was negatively correlated to the BMD of femoral neck and word's triangle (p < 0.05). The intake of cereals was found to be negatively correlated to the BMD of ward's triangle (p v 0.05). There was also negative correlation of intake of soybeans and products with the BMD of lumbar spine (p < 0.05). Weight and muscle mass were positively correlated to the BMD of both lumbar spine and femurs (p < 0.01). Significantly positive correlations between BMI, and fat mass and the BMD of lumbar spine were observed (p < 0.001). Additionally fat mass was positively correlated to the BMD of femoral neck. WHR and % body fat were positively correlated to the BMD of lumbar spine (p < 0.05). Negative correlation was found between a serum calcium level and the BMD of femoral neck (p < 0.05). In summary non-dietary factors generally showed significant correlations with the BMD of lumbar spine, while several dietary factors showed significant correlations with the BMD of femurs.

• Journal of the Korean Society of Food Culture
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• v.6 no.4
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• pp.393-401
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• 1991

In order to compare the food consumption pattern of college girls on weekday and Sunday, the food intake of college girls in a district of Pusan city was analyzed through the factor analysis method. The principal results are as follows. 1. The amount of food intake on Sunday was generally larger than the average values of the food intake on weekday except for soybean & products, meats and beverage. 2. As for correlation coefficients among the intake of each food group, on weekday, positive correlation was noted among rice, potatoes, soybean & products and sea-weeds, fish & shells and fat & oil. And confectionery & sugar showed also a positive correlation to bread, while, on Sunday, vegetables, sea-weeds and meats showed a positive correlation to rice, and other cereals and eggs showed a positive correlation to bread & noodles, too. As for the relationship among rice and bread & noodles, a negative correlation was noted both on weekday and Sunday. 3. As for the factor analysis of the food intake on weekday through the correlation matrix, in the first factor, soybean & products, fat & oil, sea-weeds, rice and fish & shells showed comparatively large factor load, and in the second factor, meats, kimchi, vegetables, soybean & products, fruits and fish & shells showed large factor load. Here the first factor showed the Korean dietary life and the second factor showed subsidiary food (control nutrient) factor. In case of the food intake on Sunday, in the first factor, rice, meats, sea-weeds, soybean & products and vegetables showed large factor load, and in the second factor, fish & shells, vegetables, fat & oil, fruits and rice showed large factor load. Accordingly, the first factor and the second factor were considered to show Korean dietary pattern. 4. Nutrient intake on weekday and Sunday was substantially sufficient to RDA except for energy and iron.

• Korean Journal of Construction Engineering and Management
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• v.18 no.1
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• pp.74-82
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• 2017

It is known that energy usage from Korean Universities was growing rapidly in the early 2000s. But since 2011, the change was caused by GHG emissions regulation enforced by the government. The purpose of this research was to find the characteristics and trends of greenhouse gas emissions from major universities in Korea according to the each university's data and information. The result shows that GHG emissions from University have increased steadily prior to enforcement by 4-5% annually, but the rate of increase marked 0.5~1% in 2011~2013 is the season of emission regulation and the total amount of emissions decreased 3%~5% in 2014~2015 while preparing an emissions trading scheme. Therefore we can say that the enforcement of GHG reduction such as energy target management system makes a visible effect at least in the University sector that level of GHG emissions is from $75kg/m^2$ to $58Kg/m^2$ for seven years. Another result says that the size of research fund is the main factor that affects the amount of GHG emissions before 2011, but the size of building area has been a new factor influencing the GHG emission since 2013. Thus we suggest that the criteria for evaluating the level of GHG emission from University is suitable if it is based on the building area intensity.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.304-310
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• 1997

In greenhouse, a mixed solution of Mn-54, Co-60, Sr-85 and Cs-137 was applied to the soil of culture boxes 2 days before sowing cucumber and at 4 different times during its growth for measuring their transfer factors (TFs) for fruit and migration in soil. TFs varied with radionuclide, application time and harvest time by factor of up to about 60. Variations in TFs with application time showed different patterns among radionuclides. TFs decreased on the whole in the order of Sr-85 > Mn-54 > Co-60 > Cs-137. TFs of Mn-54, Co-60 and Cs-137 mixed with topsoil before sowing were a little higher than those for the soil-surface application made at an early growth stage while no difference in Sr-85 TF was found. After harvest, soil concentrations of the radionuclides applied at an early growth stage were examined. They decreased with increasing soil depth and 80${\sim}$99% of the radioactivity remained in the top 3cm. Soil pemeation of the radionuclides migration decreased in the order of Sr-85 > Mn-54 > Co-60 > Cs-137. The present data can be utilized in estimating radionuclide concentration in cucumber fruit, taking proper measures for its harvest and consumption and designing the best way of soil decontamination following an radioactive deposition during the cucummber growing season.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.149-154
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• 2007

The zinc prosphate film treatments used to lubricating treatment of mostly cold forging processes. But there are several problems happened to lubricating treatment process such as happening harmful environment on person, complex lubrication processing occurring in energy and time consumption, eco-destructive and chemical by-product generation, the needs of waste disposal etc. As a result, a water-soluble lubricant was developed to replace the perfect or some of the zinc prosphate film in the world. In order to solve these problems, this study evaluated the performance of the typical water-soluble. In this study, for these requirement inquiry of two part. First, about possibility of replace zinc phosphate lubricant, quantitatively evaluation developed of water-soluble lubricant for cold forging vs zinc phosphate lubricant. Second, About optimization of coating Process use to equipment with practicable automatic coating Process. The performance evaluation of these lubricants was conducted using the double cup extrusion test and spike forging test. With the use of the commercial FE code DEFORM, friction factor calibration curves, i.e. cup height ratio vs. punch stroke and spike height vs. punch stroke, were established for different friction factor values. By matching the cup height ratio and the punch stroke and spike height vs. punch stroke from experiment to that obtained from FE simulations, the friction factor of the lubricants was determined. Survey of comparative analysis use to SEM that sprayed lubricant surface structure of grain shape and characteristic of lubricant performance based on grain shape and deformed lubricant surface expansion. As a result, developed lubricant were found to perform comparable to or better than zinc phosphate. And thought this result, innovatively cope with generated problem of existing lubrication process.

• Molecules and Cells
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• v.45 no.6
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• pp.413-424
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• 2022

Suppressor of mothers against decapentaplegic homolog (SMAD) 4 is a pluripotent signaling mediator that regulates myriad cellular functions, including cell growth, cell division, angiogenesis, apoptosis, cell invasion, and metastasis, through transforming growth factor β (TGF-β)-dependent and -independent pathways. SMAD4 is a critical modulator in signal transduction and functions primarily as a transcription factor or cofactor. Apart from being a DNA-binding factor, the additional SMAD4 mechanisms in tumor suppression remain elusive. We previously identified methyl malonyl aciduria cobalamin deficiency B type (MMAB) as a critical SMAD4 binding protein using a proto array analysis. This study confirmed the interaction between SMAD4 and MMAB using bimolecular fluorescence complementation (BiFC) assay, proximity ligation assay (PLA), and conventional immunoprecipitation. We found that transient SMAD4 overexpression down-regulates MMAB expression via a proteasome-dependent pathway. SMAD4-MMAB interaction was independent of TGF-β signaling. Finally, we determined the effect of MMAB downregulation on cancer cells. siRNA-mediated knockdown of MMAB affected cancer cell metabolism in HeLa cells by decreasing ATP production and glucose consumption as well as inducing apoptosis. These findings suggest that SMAD4 controls cancer cell metabolism by regulating MMAB.