• Journal of Korean Society of Water and Wastewater
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• v.31 no.4
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• pp.303-310
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• 2017

Pressure retarded osmosis(PRO) has attracted much attention as potential technology to reduce the overall energy consumption for reverse osmosis(RO) desalination. The RO/PRO hybrid process is considered as the most logical next step for future desalination. The PRO process aims to harness the osmotic energy difference of two aqueous solutions separated by a semipermeable membrane. By using the concentrated water(RO brine) discharged from existing RO plants, the PRO process can effectively exploit a greater salinity gradient to reduce the energy cost of processing concentrated water. However, in order to use RO brine as the draw solution, PRO membrane must have high water flux and enough mechanical strength to withstand the high operational pressure. This study investigates the development of a thin film composite PRO membrane and spiral wound module for high power density. Also, the influence of membrane backing layer on the overall power density was studied using the characteristic factors of PRO membranes. Finally, the performance test of an 8-inch spiral wound module was carried out under various operating conditions(i.e. hydraulic pressure, flow rate, temperature). As the flow rate and temperature increased under the same hydraulic pressure, the PRO performance increased due to the growth of water permeability coefficient and osmotic pressure. For a high performance PRO system, in order to optimize the operating conditions, it is highly recommended that the flow pressure be minimized while the flow rate is maintained at a high level.

• IEMEK Journal of Embedded Systems and Applications
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• v.6 no.5
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• pp.287-293
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• 2011

As chip multiprocessors have been widely adopted in embedded systems, achieving both high performance and low power consumptions of parallel applications becomes challenging. In order to meet these requirements, it is crucial for developers to analyze the performance and energy consumption of parallel applications. In this paper, we propose a tool for profiling and optimizing the performance and energy consumption of OpenMP applications (energy PROfiler and analyzer for OpenMP: ePRO-OMP). The main advantage of ePRO-OMP is that it can analyze both the performance and energy consumption of each parallel region of an OpenMP application, which can help developers find the bottleneck of parallel applications in detail.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.3
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• pp.321-325
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• 2016

The Pressure Retarded Osmosis (PRO) is the next generation desalination technique and is considered as a eco-friendly energy. This was conducted to evaluate the effect of the temperature and pressure on the PRO performance. The flux of the permeation was measured under different operating conditions and estimated the power density. An improvement of PRO performance is depend on increasing solution temperature and optimum pressure. The effect of increasing feed solution temperature has stronger impact on the PRO performance comparing to the draw solution temperature. The reason of the results was due to the change of osmotic power, viscosity, water permeability and structure parameter(s).

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.1
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• pp.131-139
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• 2014

This study was performed to determine the effect of dietary supplementation of procyanidin on growth performance, blood characteristics, and immune function in growing pigs. In experiment 1 (Exp. 1), thirty-two crossbred pigs with an initial BW of $19.2{\pm}0.3$ kg were allocated into 4 treatments for an 8-wk experiment: i) CON (basal diet), ii) MOS 0.1 (basal diet+0.1% mannanoligosaccharide), iii) Pro-1 (basal diet+0.01% procyanidin), and iv) Pro-2 (basal diet+0.02% procyanidin). Pigs fed Pro-1 and Pro-2 diets had greater (p<0.05) gain:feed ratio compared with those fed CON or MOS 0.1 diets. Serum creatinine concentration was less (p<0.05) in Pro-2 treatment than those in CON, MOS 0.1 and Pro-1 treatments. In Exp. 2, twelve pigs (BW $13.4{\pm}1.3$ kg) received basal diet with i) 0 (CON), ii) 0.02% (Pro-0.02%), and iii) 0.04% procyanidin (Pro-0.04%) for 4 wk. Concentration of platelets was lower (p<0.05) in the Pro-0.04% group compared to CON at 24 h after lipopolysaccharide (LPS) challenge. In addition, secretion of cytokines from cultured peripheral blood mononuclear cells (PBMC) in the presence or absence of procyanidin was examined. The levels of interleukin (IL)-$1{\beta}$, IL-6 and tumor necrosis factor (TNF)-${\alpha}$ were lower (p<0.05) in Pro (LPS-stimulated PBMCs+procyanidin) than those in CON (LPS-stimulated PBMCs+PBS) at 4 h after LPS challenge. These data suggest that dietary addition of procyanidin improves feed efficiency and anti-inflammatory cytokines of pigs.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.300-305
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• 2008

Using WindPRO that was software for windfarm design developed by EMD from Denmark, wind resources for the western Jeju island were analyzed, and the performance of WindPRO prediction was evaluated in detail. The Hansu site and the Yongdang site that were located in coastal region were selected, and wind data for one year at the two sites were analyzed using WindPRO. As a result, the relative error of the Prediction for annual energy Production and capacity factor was about ${\pm}20%$. For evaluating wind energy more accurately, it is necessary to obtain lots of wind data and real electric power production data from real windfarm.

• Korean Journal of Remote Sensing
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• v.15 no.4
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• pp.339-348
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• 1999

To extract value-added products which are important in scientific area and practical life, e.g. digital elevation models, ortho-rectified images and geometric corrected images, Satellite Technology Research Center at Korea Advanced Institute of Science and Technology has developed a satellite image processing software called "Valadd-Pro". In this paper, "Valadd-Pro" software is briefly introduced and its main components such as precise geometric correction, ortho-rectification and digital elevation model extraction component are described. The performance of "Valadd-Pro" software was assessed on 10m resolution 6000 $\times$ 6000 SPOT panchromatic images (60km $\times$ 60km) using ground control points from GPS measurements. The height accuracy was measured by comparing our results with 100m resolution $DTEDs^{1)}$ produced by USGS and 60m resolution DEMs generated from digitized contours produced by National Geography Institute. Also, to show the superior performance of "Valadd-Pro" software, we compared the performance with that of commonly used PCI$\circledR$ commercial software. Based on the results, the geometric correction of "Valadd-Pro" software needs fewer ground control points than that of PCI$\circledR$ software and the ortho-rectification of "Valadd-Pro" software shows similar performance to that of PCI$\circledR$ software. In the digital elevation model extraction, "Valadd-Pro" software is two times more accurate and four times faster than PCI$\circledR$ software.ccurate and four times faster than PCI$\circledR$ software.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.184.1-184.1
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• 2010

In order to research the way to evaluate wind resource without actual Met Mast data, this paper has been carried out on the southeastern region of Jeju island, Korea. Although wind turbine has been an economical alternative energy resource, misjudging the prediction of lifetime or payback period occurs because of the inaccurate assessment of wind resource and the location of wind turbine. Using WindPRO(Ver. 2.7), a software for wind farm design developed by EMD from Denmark, wind resources for the southeastern region of Jeju island was analyzed, and the performance of WindPRO prediction was evaluated in detail. Met Mast data in Su-san 5.5Km far from Samdal wind farm, AWS in Sung-san 4.5km far from Samdal wind farm, and Korea Wind Map data had been collected for this work.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.3
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• pp.299-312
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• 2016

The main objective of this paper is to develop computer simulation program for performance evaluation and cost estimation of a reverse osmosis (RO) and pressure-retarded osmosis (PRO) hybrid process to propose guidelines for its economic competitiveness use in the field. A solution-diffusion model modified with film theory and a simple cost model was applied to the simulation program. Using the simulation program, the effects of various factors, including the Operating conditions, membrane properties, and cost parameters on the RO and RO-PRO hybrid process performance and cost were examined. The simulation results showed that the RO-PRO hybrid process can be economically competitive with the RO process when electricity cost is more than 0.2 $/kWh, the PRO membrane cost is same as RO membrane cost, the power density is more than $8W/m^2$ and PRO recovery is same as 1/(1-RO recovery).

• Journal of Korean Society of Water and Wastewater
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• v.30 no.3
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• pp.271-278
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• 2016

Recently, reverse osmosis (RO) is the most common process for seawater desalination. A common problem in both RO and thermal processes is the high energy requirements for seawater desalination. The one energy saving method when utilizing the osmotic power is utilizing pressure retarded osmosis (PRO) process. The PRO process can be used to operate hydro turbines for electrical power production or can be used directly to supplement the energy required for RO desalination system. This study was carried out to evaluate the performance of both single-stage PRO process and two-stage PRO process using RO concentrate for a draw solution and RO permeate for a feed solution. The major results, were found that increase of the draw and feed solution flowrate lead to increase of the production of power density and water permeate. Also, comparison between CDCF and CDDF configuration showed that the CDDF was better than CDCF for stable operation of PRO process. In addition, power density of two-stage PRO was lower than the one of single-stage. However, net power of two-stage PRO was higher than the one of single-stage PRO.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.1
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• pp.71-77
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• 1998

The experiment was conducted to evaluate Bio-V-Pro as an alternative protein source in broiler diets. Treatments were control, Bio-V-Pro 1% (BP 1), Bio-V-Pro 3% (BP 3), and Bio-V-Pro 5% (BP 5). During the starter period, all treated groups showed beter performance than control group in weight gain and feed intake (p < 0.05). The best FCR was observed in BP 1 group and the worst was found in BP 5 group. For the overall period, chicks fed BP 1 and BP 3 diets gained more than the chicks fed the control and BP 5 diets. All Bio-V-Pro fed groups consumed more feed than the control group (p < 0.05). FCR were similar between the control and BP 1 group, but BP 3 and BP 5 groups showed higher FCR than the control group. During the starter period, all BP groups showed better utilizability of crude protein, crude ash and phosphorus than the control group (p < 0.05). For the finisher period, except for the BP 5 group, the nutrient utilizability was not significantly different in most nutrients. Nutrients utilizability had a tendency (not significant) to decrease as the level of Bio-V-Pro in the diet was increased. Lysine utilizability was not affected by the dietary treatment, however, methionine utilizability was higher in BP 1 and BP 3 group than in the control group. From the results of this experiment, it seems that Bio-V-Pro is a good alternative protein source which can replace fish meal in starter diet up to 3% of the diet effectively.