• Journal of the East Asian Society of Dietary Life
• /
• v.17 no.1
• /
• pp.1-10
• /
• 2007

The effects of mulberry-leaf powder Tofu(MPT) on anthropometric measurements, including bone mineral density(BMD) in the right carpus, biochemical bone turnover markers, serum levels of lipids and macrominerals, were investigated in 30 smoking male adults who lived in Choongnam were given MPT(100 g/day) for 4 weeks. The average ages, number of smoked cigarettes and packyear were 22.38 years, 15.12/day and 3.54 years, respectively. The nutrient contents per 100 g MPT were 86.10 kcal energy, 8.98 g protein, 0.53 mg fiber, 211.33 mg Ca and 1.59 g fat. Anthropometric measurements, including dietary intake using the 24-hours recall method, carpal BMD using DEXA, serum levels of protein, albumin and glucose, lipid profiles (cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol) with Al(atherosclerosis index), HTR, CRF, LHBt, some biomarkers of BMD(serum alkaline phosphatase activity, osteocalcin, urinary DPD), and serum macrominerals(Ca, Ca/P ratio, Mg) and Pb were analyzed before and after consumption of MPT. After MPT consumption, dietary intakes of plant protein, total Ca and plant Ca increased significantly, but there were no significant differences in anthropometric measurements, BMD with bone metabolism markers, serum levels of protein, albumin or glucose, lipid profiles with AI, HTR, LHR and CRF.

• Journal of the East Asian Society of Dietary Life
• /
• v.17 no.1
• /
• pp.11-19
• /
• 2007

This study was designed to evaluate Saturday nutrition classes for obese elementary students in Chungnam Province. Obesity index, nutrient intake, nutrition knowledge, nutrition attitude, and self-satisfaction of 36 obese elementary students were compared before and after attending nutrition classes every other Saturday for 3 months. The average age, height, weight, body fat, % body fat, and obesity index were 11.9 years, 145.5 cm, 53.3 kg, 24.5 kg, 45.7%, and 32.4%, respectively. Most of the subjects(94.5%) viewed themselves as fat. Sixty-three percent of children were discontent with their body-image. All answered that they have experience with weight control. The major methods of weight control were exercise and reduction of snacks. The mean serum cholesterol, blood glucose, GOT/GPT, and hemoglobin were 177.4 mg/dL, 90.4 mg/dL, 25.8/25.5 IU/L, 14.5 g/dL, respectively. After attending nutrition classes, the daily intakes of energy, plant protein, plant fat, carbohydrate, crude fiber, and cholesterol increased significantly. The scores for nutrition knowledge, nutrition attitude, and self-satisfaction also increased after nutrition classes, but there were no significant differences. Percent body fat decreased significantly after nutrition classes. In conclusion, nutrition education for elementary students is effective for the prevention and control of obesity. Further research is needed to develop a systematic program of nutrition education for obese children.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.19 no.1
• /
• pp.37-43
• /
• 2015

This paper presents a detailed procedure for a nonlinear soil-structure interaction of a seismically isolated NPP(Nuclear Power Plant) structure using the boundary reaction method (BRM). The BRM offers a two-step method as follows: (1) the calculation of boundary reaction forces in the frequency domain on an interface of linear and nonlinear regions, (2) solving the wave radiation problem subjected to the boundary reaction forces in the time domain. For the purpose of calculating the boundary reaction forces at the base of the isolator, the KIESSI-3D program is employed in this study to solve soil-foundation interaction problem subjected to vertically incident seismic waves. Wave radiation analysis is also employed, in which the nonlinear structure and the linear soil region are modeled by finite elements and energy absorbing elements on the outer model boundary using a general purpose nonlinear FE program. In this study, the MIDAS/Civil program is employed for modeling the wave radiation problem. In order to absorb the outgoing elastic waves to the unbounded soil region, spring and viscous-damper elements are used at the outer FE boundary. The BRM technique utilizing KIESSI-3D and MIDAS/Civil programs is verified using a linear soil-structure analysis problem. Finally the method is applied to nonlinear seismic analysis of a base-isolated NPP structure. The results show that BRM can effectively be applied to nonlinear soil-structure interaction problems.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.19 no.1
• /
• pp.29-36
• /
• 2015

Base isolation is considered as a seismic protective system in the design of next generation Nuclear Power Plants (NPPs). If seismic isolation devices are installed in nuclear power plants then the safety under a seismic load of the power plant may be improved. However, with respect to some equipment, seismic risk may increase because displacement may become greater than before the installation of a seismic isolation device. Therefore, it is estimated to be necessary to select equipment in which the seismic risk increases due to an increase in the displacement by the installation of a seismic isolation device, and to perform research on the seismic performance of each piece of equipment. In this study, modified NRC-BNL benchmark models were used for seismic analysis. The numerical models include representations of isolation devices. In order to validate the numerical piping system model and to define the failure mode, a quasi-static loading test was conducted on the piping components before the analysis procedures. The fragility analysis was performed by using the results of the inelastic seismic response analysis. Inelastic seismic response analysis was carried out by using the shell finite element model of a piping system considering internal pressure. The implicit method was used for the direct integration time history analysis. In addition, the collapse load point was used for the failure mode for the fragility analysis.

• Korean Journal of Agricultural Science
• /
• v.23 no.2
• /
• pp.272-284
• /
• 1996

The present study has quantitatively assessed the regional production, income and employment impact resulting from the construction and operation of nuclear power plant (NPP) upon the domestic local areas by applying the regional input-output analysis model to the case of Wolsong unit-l site. The conclusions regarding the most likely regional economic impacts upon the wolsong site are summarized as follows: 1. The income multipliers are calculated to be 1.563 for the construction phase and 1.500 for the operation phase. These values are relatively high compared with those of other conventional facilities. 2. The level of total employee's wage induced employment associated with the construction phase has been estimated to be 37,000 while that with the operational phase in 1990 to be 5,610. 3. With relation to the aspect of resident welfare it is found that the industrial sector associated with electricity, gas and water supply have remarkably improved with the construction of the NPP. 4. The NPP siting has induced substantial changes in interindustry (input-output) structures of the Wolsong unit-l site which is one of the rural areas where all the domestic NPPs are sited. Such changes are attributed to the industrial recomposition of the region. 5. With the application of other regional economic analysis models and the use of more sufficient regional data, other detailed studies on the economic impact analysis of domestic NPP-related facility sitings are suggested to be carried out further since the influence of NPP sitings is significant to the national economic impact as well as the regional economic impact.

• Nuclear Engineering and Technology
• /
• v.17 no.4
• /
• pp.247-255
• /
• 1985

This paper describes a new method for the design of variable structure model-following control systems(VSMFC). This design concept is developed using the theory of variable structure systems (VSS) and slide mode. The new results are presented on the sliding control methodology to achieve accurate tracking for a class of nonlinear, multi-input multi-output(MIMO), time varying systems in the presence of parameter variations. The design requires little computational effort. The dynamic response is insensitive to parameter variations. The feasibility and the advantages of the method are illustrated by applying it to a 1000 MWe boiling water reactor(BWR). The control is studied in the range of 85%∼90% of rated power for load-following control. A set of 12 nonlinear differential equations is used to simulate the total plant. A 6-th order linear model has been developed from these equations at 85% of rated power. The obtained controller is shown by simulations to be able to compensate for a plant parameter variation over a wide power range.

• Environmental and Resource Economics Review
• /
• v.27 no.1
• /
• pp.161-194
• /
• 2018

This study examines performances of cooperatives relative to investor-owned firms in the US electric power industry. Using a panel data of firms from 2001 to 2014, the results show that cooperatives operate under conditions of more difficult capital constraints associated with the higher cost of debt and limited access to external equity capital. While investor-owned utilities, especially the large utilities that are less capital constrained, take benefits from substantial scale economies existing in the industry, the marginal cost of operation substantially increases with output for cooperatives. I do not find differences in profitability between the two ownership structures, measured by return on assets and return on equity. Plant capacity utilization, which is a measure of plant efficiency conditional on the operation, is also not statistically different between the two groups.

• Environmental Engineering Research
• /
• v.19 no.2
• /
• pp.123-130
• /
• 2014

Percolation is the important process of extracting the soluble constituents of a fine mesh, porous substance by passage of a liquid through it. In this study, bio-wastes were percolated under various conditions through continuous percolation processes, and the energy potential of percolate was evaluated. The representative bio-wastes from the K composting plant in Darmstadt, Germany were used as the sample for percolation. The central objective of this study was to determine the optimal amount of process water and the optimum duration of percolation through the bio-wastes. For economic reasons, the retention time of the percolation medium should be as long as necessary and as short as possible. For the percolation of the bio-wastes, the optimal percolation time was 2 hr and maximum percolation time was 4 hr. After 2 hr, more than two-thirds of the organic substances from the input material were percolated. In the first percolation process, the highest yields of organic substance were achieved. The best percolation of the bio-wastes was achieved when the process water of 2 L for the first percolation procedure and then the process water of 1.5 L for each further percolation procedure for a total 8 L for all five procedures were used on 1,000 g fresh bio-waste. The gas formation potentials of 0.83 and $0.96Nm^3/ton$ fresh matter (FM) were obtained based on the percolate from 1 hr percolation of 1,000 g bio-waste with the process water of 2 L according to the measurement of the gas formation in 21 days (GB21). This method can potentially contribute to reducing fossil fuel consumption and thus combating climate change.

• Journal of Advanced Marine Engineering and Technology
• /
• v.19 no.1
• /
• pp.60-70
• /
• 1995

In the field of marine transportation the energy saving is one of the most important factors for profit. In order to reduce the fuel oil consumption the ship's propulsion efficiency must be increased as much as possible. The propulsion efficiency depends upon a combination of an engine and a propeller. The propeller has better efficiency as lower rotational speed. This situation led the engine manufacturers to design the engine that has lower speed, longer stroke and a small number of cylinders. Consequently the variation of rotational torque became larger than before because of the longer delay-time in the fuel oil injection process and an increased output per cylinder. As this new trends the conventional mechanical-hydrualic governors for engine speed control have been replaced by digital speed controllers which adopted the PID control or the optimal control algorithm. But these control algorithms have not enough robustness to suppress the variation of the delay-time and the parameter pertubation. In this paper we consider the delay-time and the perturbation of engine parameters as the modeling uncetainties. Next we design the controller which has zero offset in steady state engine speed, based on the two-degree-of-freedom control theory and $\mu$-synthesis. Thd validity of the controller is investigated through the response simulation. We use a personal computer and an analog computer as the digital controller and the engine (plant) part respectively. And, we certify that the designed controller maintains its performance even though the engine parameters may vary.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.30 no.2
• /
• pp.85-90
• /
• 2010

The infrared energy is emitted in the infrared wavelength range that corresponds to the surface temperature of a object which has temperature that is over the absolute the temperature(OK). The infrared thermography (IRT) is a non-destrnctive testing method that provides thermal video for the user in real-time by converting the infrared quantity that is detected by the infrared detector into temperature. The pipes of nuclear power plant(NPP) could be thinned by the corrosion and fatigue and the defect could lead to a big accident. For this reason, the effective non-destructive testing method is necessary. In this study, the relationship between the measured temperature and the defect depth or size of NPP pipes were recognized and that was applied to detect the wall thinning defects of NPP pipes.