• Clean Technology
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• v.24 no.2
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• pp.127-134
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• 2018

To reduce the environmental pollution by $NO_x$ from ship engine, International maritime organization (IMO) announced Tier III regulation, which is the emmision regulation of ship's exhaust gas in Emission control area (ECA). Selective catalytic reduction (SCR) process is the most commercial $De-NO_x$ system in order to meet the requirement of Tier III regulation. In generally, commercial ceramic honeycomb SCR catalyst has been installed in SCR reactor inside marine vessel engine. However, the ceramic honeycomb SCR catalyst has some serious issues such as low strength and easy destroution at high velocity of exhaust gas from the marine engine. For these reasons, we design to metallic structured catalyst in order to compensate the defects of the ceramic honeycomb catalyst for applying marine SCR system. Especially, metallic structured catalyst has many advantages such as robustness, compactness, lightness, and high thermal conductivity etc. In this study, in order to support catalyst on metal substrate, coating slurry is prepared by changing binder. we successfully fabricate the metallic structured catalyst with strong adhesion by coating, drying, and calcination process. And we carry out the SCR performance and durability such as sonication and dropping test for the prepared samples. The MFC01 shows above 95% of $NO_x$ conversion and much more robust and more stable compared to the commercial honeycomb catalyst. Based on the evaluation of characterization and performance test, we confirm that the proposed metallic structured catalyst in this study has high efficient and durability. Therefore, we suggest that the metallic structured catalyst may be a good alternative as a new type of SCR catalyst for marine SCR system.

• Korean Journal of Poultry Science
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• v.39 no.3
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• pp.167-175
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• 2012

This study was undertaken to assess dietary CP and ME concentrations for optimum growth performance and carcass characteristics of Korean Native male ducks. In a $3{\times}3$ factorial arrangement, 1-d-old Korean Native male ducks were completely randomized design to experimental diets with 3,000, 2,900, and 2,800 kcal of ME/kg of diet; each contained 23, 22, and 21% CP, respectively, from 0 to 3 wk of age. From 4 to 8 wk of age, experimental diets had 3,100, 3,000, and 2,900 kcal of ME/kg of diet, and each contained 19, 18, and 17% CP, respectively. Each dietary treatment was replicated 4 times, and feed and water were provided ad libitum. Body weight, feed intake and uniformity were measured at 3 wk and 8 wk, and carcass characteristics were evaluated at 8 wk. As CP increased from 21 to 23 %, the body weight, BW gain and feed conversion ratios (FCR) linearly improved (P<0.01) during 0 to 3 wk of age. From 4 to 8 wk of age, the body weight, feed intake, BW gain, FCR and uniformity were not different (P>0.05). Carcass ratios of birds fed 3,000 kcal of ME/kg diets from 3 to 8 wk of age were quadratically increased significantly (P<0.01). As ME and CP increased, respectively, relative weight of liver weight per 100 g of BW was linearly decreased (P<0.01). Relative weights of left breast, thigh and drumstick weight per 100 of BW were not different (P>0.05). Also, breast meat color, pH, cooking loss and shear force were not different (P>0.05). Thus, diets with 2,800 kcal of ME/kg and 23% CP or with 2,900 kcal of ME/kg and 17% CP at 0 to 3 wk and 4 to 8 wk, respectively, were used more efficiently. However, diets with 3,000 kcal of ME/kg at 4 to 8 wk in carcass rate was quadratically increased.

• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.182-190
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• 2005

The fiber Raman amplifier(FRA) is a distinctly advantageous technology. Due to its wider, flexible gain bandwidth, and intrinsically lower noise characteristics, FRA has become an indispensable technology of today. Various FRA modeling methods, with different levels of convergence speed and accuracy, have been proposed in order to gain valuable insights for the FRA dynamics and optimum design before real implementation. Still, all these approaches share the common platform of coupled ordinary differential equations(ODE) for the Raman equation set that must be solved along the long length of fiber propagation axis. The ODE platform has classically set the bar for achievable convergence speed, resulting exhaustive calculation efforts. In this work, we propose an alternative, highly efficient framework for FRA analysis. In treating the Raman gain as the perturbation factor in an adiabatic process, we achieved implementation of the algorithm by deriving a recursive relation for the integrals of power inside fiber with the effective length and by constructing a matrix formalism for the solution of the given FRA problem. Finally, by adiabatically turning on the Raman process in the fiber as increasing the order of iterations, the FRA solution can be obtained along the iteration axis for the whole length of fiber rather than along the fiber propagation axis, enabling faster convergence speed, at the equivalent accuracy achievable with the methods based on coupled ODEs. Performance comparison in all co-, counter-, bi-directionally pumped multi-channel FRA shows more than 102 times faster with the convergence speed of the Average power method at the same level of accuracy(relative deviation < 0.03dB).

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.101-107
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• 1985

Since most farmers breeding livestocks in Korea is depended on imported feeds, the rate of self-supplying feeds is very important for a stable development of farmers. Therefore, it is considered necessary to increase the rate of self-supplying feeds. In this study, performance tests were carried out with barley and forage to find the design's parameters of hammer for a small size hammer mill which can be driven by 3.7-7.5 kW power tiller being used by most farmers. The revolution speed of hammer mill was 3000 rpm, widths of hammer were 20mm, 30mm, 40mm, and the levels of thickness of hammer were 2mm, 4mm and 6mm. Experimental materials used were barley and forage and screen openings for barley was 4.76mm, and 3.18mm for forage. The study results can be summarized as follows; 1. Results of grinding tests showed that particle sizes were 478-774 microns for barley and 350-434 microns for forage. They were decreased according to the increasing thickness and width of hammer. 2. Fineness modulus of grinded materials were 3.07-3.62 for barley and 2.69-2.93 for forage. They were inversely proportional to thickness and width of hammer. 3. The required power for grinding was 3.8-5.0 kW for barley and 0.9-1.4 kW for forage. The thickness of hammer was more important for less power requirement than width of hammer. 4. Grinding performance of a small size hammer mill was 99-170kg/kWh for barley and 11-21 kg/kWh for forage. The thickness of hammer was an important factor for grinding performance, and inversely proportional to grinding performance. For about 3.2 of fineness modulus, 4 mm thickness was the best, and an optimum width of hammer was 30mm for a small size hammer mill.

• Korean journal of food and cookery science
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• v.26 no.4
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• pp.367-380
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• 2010

Various contents of Rosa rugosa Thunb. fruit(0, 10, 20%), which is grown along the seashore of Gangwon province, were applied to apple jams having different sugar concentrations(20, 40, 60%). The resulting jams were analyzed using a sensory scoring test as well as a response surface methodology to identify the optimum conditions for the preparation of high-preference apple jams. The sensory properties based on sense of sight, smell and taste appeared to be linked to the sugar contents. It could be attributed to the presence of flavor compounds and pigments generated from the caramelization of sugar molecules during heat processing. On the other hand, rheological properties such as viscosity and spreadability were associated with Rosa rugosa fruit content, which was also verified by textural analysis of the jams. As the contents of Rosa rugosa increased, the hardness, gumminess, and chewiness of the jams decreased, which eventually might have contributed to the less thick and thus more spreadable sensory characteristics. Sensory evaluation revealed that apple jams were preferred when prepared with $\leq$10% of Rosa rugosa fruit and $\geq$55% of sugar contents. In particular, apple jams containing 10% Rosa rugosa and 60% sugar showed better mechanical qualities as well as higher sensory preference among 10 jams formulated using central composite design.

• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.43-71
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• 1999

This research is an experimental work of developing a construction material using municipal wastewater sludge as liner and cover materials for waste disposal landfill. Weathered granite soil and flyash, produced as a by-product in the power plant, were used as the primary additives to improve geotechnical engineering properties of sludge. For secondary additives, bentonite and cement were mixed with sludge to decrease the permeability and to increase the shear strength, respectively. Various laboratory test required to evaluate the design criteria for liner and cover materials, were carried out by changing the mixing ratio of sludge with the additives. Basic soil properties such as specific gravity, grain size distribution, liquid and plastic limits were measured to analyze their effects on permeability, compaction, compressibility and shear strength properties of mixtures. Laboratory compaction tests were conducted to find the maximum dry densities and the optimum moisture contents of mixtures, and their effectiveness of compaction in field was consequently evaluated. Permeability tests of variable heads with compacted samples, and the stress-controlled consolidation tests with measuring permeabilities of samples during consolidation process were performed to obtain permeability, and to find the compressibility as well as consolidational coefficients of mixtures, respectively. To evaluate the long term stability of sludges, creep tests were also conducted in parallel with permeability tests of variable heads. On the other hand, for the compacted sludge decomposed for a month, permeability tests were carried out to investigate the effect of decomposition of organic matters in sludges on its permeability. Direct shear tests were performed to evaluate the shear strength parameters of mixed sludge with weathered granite, flyash and bentonite. For the mixture of sludge with cement, unconfined compression tests were carried out to find their strength with varying mixing ratio and curing time. On the other hand, CBR tests for compacted specimen were also conducted to evaluate the trafficability of mixtures. Various test results with mixtures were assessed to evaluate whether their properties meet the requirements as liner and cover materials in waste disposal landfill.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.3
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• pp.187-194
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• 1985

This field experiment was carried out to determine the effects of thirteen different fertilizer levels of nitrogen(N), phosphorus($P_2O_5$) and potassium($K_2O$) on the content of crude protein, crude fiber, mineral constituents of product and tree growth forest pasture with 40-50% shading. The experiment was arranged as a randomized block design and performed in the suburban forest of Suweon in 1984. The results obtained are summarized as follows: 1. Crude protein content and total protein yield were higher in the plot of 28 and 42kg $N/_{10a}$, regardless of $P_2O_5\;and\;K_2O$ level, while those were the lowest in zero fertilizer and N-zero fertilizer plots. 2. The contents of lignin and silica were significantly low in the high N fertilizer level, and the contents of NDF, ADF, cellulose and hemicellulose were not affected by different fertilizer levels. However, the content of crude fiber tended to be low with high N, regardless of $P_2O_5\;and\;K_2O$. 3. The contents of N,K and $SiO_2$ of grasses were influenced by different fertilizer levels. However, those of P,Ca,Ma and Na showed little differences. 4. The recovery percentage of NPK was higher in the plot of standard fertilizer level with 28-20-24 kg/10a, and higher recovery percentage was observed in $K_2O$, followed by N and $P_2O_5$ in that order. 5. The growth of tree was increased as the level of N fertilizer was increased, but no such trend was noted by $P_2O_5\;and\;K_2O$ levels. 6. Crude protein, crude fiber, some mineral contituents of grasses, and growth of tree were influenced by N level, regardless of $P_2O_5\;and\;K_2O$. And the optimum fertilizer level of $N-P_2O_5-K_2O$ seemed to be 28-20-24 kg/10a for the production of grasses with higher quality and more yield in the forest.

• Current Research on Agriculture and Life Sciences
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• v.30 no.2
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• pp.68-75
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• 2012

This study was conducted to monitor the yields of useful substances extracted from Inonotus obliquus. Optimization of ultrasonic-assisted extraction process was carried out by using response surface methodology under different extraction conditions. A central composite design was applied to investigate the effects of independent variables such as extraction time ($X_1$), ethanol concentration ($X_2$) and extraction temperature ($X_3$) on dependent variables such as soluble solid yield ($Y_1$), total phenol contents ($Y_2$), total flavonoid contents ($Y_3$) and browning color($Y_4$). Soluble solid yield was affected by ethanol concentration and extraction temperature. The maximum soluble solid yield was 18.02% at 20.47 min ($X_1$), 42.85% ($X_2$) and $69.57^{\circ}C$ ($X_3$) in saddle point. Total phenol contents were highly affected by ethanol concentration and extraction temperature. The maximum total phenol contents were 71.57mg GAE/g at 21.60min ($X_1$), 45.19% ($X_2$), $69.68^{\circ}C$ ($X_3$). The electron donating ability was affected by extraction temperature and extraction time. Total flavonoid contents were affected by only extraction temperature. The maximum total flavonoid contents were 35.98 mg RE/g at 22.53min ($X_1$), 46.37% ($X_2$), $69.56^{\circ}C$ ($X_3$) in saddle point. The browning color was highly affected by extraction time, ethanol concentration and extraction temperature. The maximum browning color was at 22.00 min ($X_1$), 46.89% ($X_2$), $69.71^{\circ}C$ ($X_3$) in saddle point. As a result, the optimum extraction conditions were predicted; extraction time of 21.50 min, ethanol concentration of 44.87% and extraction temperature of $69.635^{\circ}C$.

• The KIPS Transactions:PartD
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• v.15D no.2
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• pp.223-234
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• 2008

Recently the web service area provides the efficient integrated environment of the internal and external of corporation and enterprise that wants the introduction of it is increasing. Also the web service develops and the new business model appears, the domestic enterprise environment and e-business environment are changing caused by web service. The web service which provides the similar function increases, most the method which searches the suitable service in demand of the user is more considered seriously. When it needs to choose one among the similar web services, service consumer generally needs quality information of web service. The problem, however, is that the advertised QoS information of a web service is not always trustworthy. A service provider may publish inaccurate QoS information to attract more customers, or the published QoS information may be out of date. Allowing current customers to rate the QoS they receive from a web service, and making these ratings public, can provide new customers with valuable information on how to rank services. This paper suggests the agent-based quality broker architecture which helps to find a service providing the optimum quality that the consumer needs in a position of service consumer. It is able to solve problem which modify quality requirements of the consumer from providing the architecture it selects a web service to consumer dynamically. Namely, the consumer is able to search the service which provides the optimal quality criteria through UDDI browser which is connected in quality broker server. To quality criteria value decision of each service the user intervention is excluded the maximum. In the existing selection architecture, the objective evaluation was difficult in subjective class of service selecting of the consumer. But the proposal architecture is able to secure an objectivity with the quality criteria value decision where the agent monitors binding information in consumer location. Namely, it solves QoS information of service which provider does not provide with QoS information sharing which is caused by with feedback of consumer side agents.

• Food Science and Preservation
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• v.19 no.4
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• pp.470-476
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• 2012

Enzymatic action and microbial growth degrade the quality of fresh-cut lettuce. Browning, a bad smell, and softening during storage are the major forms of quality deterioration. Health-oriented consumers tend to avoid foods treated with chemicals to maintain their freshness. This study was conducted to evaluate the change in the quality of fresh-cut lettuce with combined low-temperature blanching (LB) and ultrasonication (US). The optimum condition was selected using the response surface methodology (RSM), through a regression analysis with the following independent variables; the ultrasonication time (X1), blanching temperature (X2), blanching time (X3), and dependent variable; ${\Delta}E$ value (y). It was found that the condition with the lowest ${\Delta}E$ value occurred with combined 90s US and $45^{\circ}C$ 90s LB (US+LB). The combined treatment group (US+LB) was stored at $10^{\circ}C$ for 9 days with the control group and each single-treatment group, with low-temperature blanching and ultrasonication. Overall, the US+LB group had a significantly high $L^*$ value, which indicates significantly low $a^*$, $b^*$, ${\Delta}E$, browning index, PPO, and POD activity values, and a low total bacteria count (p < 0.05). The US+LB group also had the highest sensory score (except for aroma and texture; p > 0.05).