• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.4
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• pp.570-576
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• 2014

Response surface methodology (RSM) was applied to optimize the microwave-assisted extraction (MAE) conditions for electron-donating ability, total phenol content, and total flavonoid content of Ligustrum lucidum Aiton. Ligustrum lucidum Aiton from different regions was tested, and Ligustrum lucidum Aiton from Haenam was chosen due to its higher total phenolic content, total flavonoid content, DPPH radical scavenging activity and ABTS radical scavenging activity compared to the other samples. Central composite design was used to optimize extraction of Ligustrum lucidum Aiton from Haenam as well as determine the effects of extraction temperature ($X_1$) and extraction time ($X_2$) on dependent variables ($Y_n$). Determination coefficients ($R^2$) of the regression equations for dependent variables ranged from 0.8858 to 0.9517. The optimum points were $131.68^{\circ}C$ for extraction temperature and 5.49 min for extraction time. Predicted values of the optimized conditions were acceptable when compared to experimental values.

• The Journal of Engineering Geology
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• v.27 no.4
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• pp.405-416
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• 2017

This study evaluated a model unconfined aquifer comprising a sand or gravel layer, a filter layer, a pumping well, and an observation well. The model was employed in step drawdown tests and then used to assess the permeability of each test tank. The optimal yield and well efficiency were then calculated. Evaluation of yield by step in sand layer filters of equal thickness gave optimized watering rates of 22.03 L/min in the double filter and 19.71 L/min in the single filter. The double filter's yield was 115.0% that of the single filter. A comparison of double and single filters, each 10 cm thick, showed the double filter to have a maximum yield of 182.7%. Yields for the gravel layer were 73.56 L/min for a double filter and 65.47 L/min for a single filter of the same thickness; the former value is 112.3% of that of the latter. Comparison of double and single filters with 10-cm-thick gravel layers revealed that the double filter had a maximum yield of 160.9%. Results for sand wells showed the double filter to have a maximum efficiency of 70.4% and the single filter to have a minimum efficiency of 37.1%. Gravel-layer well efficiencies were >66.5% for both double and single filters (each 30 cm thick), but only 22.5% for a 10-cm-thick single filter. This study confirms that permeability improved as the filter material became thicker; it also shows that a double filter has a higher yield and well efficiency than a single filter. These results can be applied to the practical design of wells.

• Food Science and Preservation
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• v.17 no.2
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• pp.281-289
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• 2010

We determined the optimum ethanolic conditions for extraction of $\gamma$-oryzanol and other functional components from rice bran, using response surface methodology (RSM). A central composite design was used to investigate the effects of the independent variables of solvent ratio ($X_1$), extraction temperature ($X_2$), and extraction time ($X_3$), on dependent variables including yield ($Y_1$), total phenolic content ($Y_2$), electron-donating activity ($Y_3$), ferulic acid level ($Y_4$), and $\gamma$-oryzanol concentration ($Y_5$). Solvent ratio and extraction temperature were the most important factors in extraction. The maximum yield was at 22.56 mL/g ($X_1$), 78.19C ($X_2$), and 522.15 min ($X_3$), at the saddle point. Total phenolic levels were little affected by solvent ratio or extraction temperature. The maximum concentration of extracted total phenolics was 90.78mg GAE/100 g at 21.26 mL/g, $94.65^{\circ}C$, and 567.97 min. A maximum electron-donating ability of 54.72% was obtained with the parameters 20.20 mL/g,$81.89^{\circ}C$, and 701.87 min, at the highest point. The maximum level of ferulic acid components was 210.47 mg/100g at 5.22 mL/g, $79.66^{\circ}C$, and 575.24 min. In addition, the maximum $\gamma$-oryzanol concentration was 660.39 mg/100g at 5.10 mL/g, $81.83^{\circ}C$, and 587.39 min. The optimum extraction conditions were a solvent ratio of 10.45 mL/g, $80^{\circ}C$ extraction temperature, and 535 min extraction time. Predicted extraction levels under optimized conditions were in line with experimental values.

• Culinary science and hospitality research
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• v.22 no.2
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• pp.13-28
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• 2016

This study performed quantitative analysis of isoflavone glycoside contents on Buseoktae, Daewon, Wooram beans and cheonggukjang made of Buseoktae beans from the LC/MS/MS. Also, the experiment carried out by means of RSM(response surface methodology), which included 10 experimental points for the two independent variables addition(40, 55, 70 g) and time(2, 3, 4 min) from the beginning point to boil of cheonggukjang. These were optimized using a Face-centered central composite design. Daidzein contents were $212.16{\mu}g/mL$ in Buseoktae, $212.21{\mu}g/mL$ in daewon, $158.54{\mu}g/mL$ in wooram beans. Genistein contents were $318.84{\mu}g/mL$ in Buseoktae, $310.50{\mu}g/mL$ in daewon, $262.71{\mu}g/mL$ in wooram beans. Total isoflavone contents were $532.50{\mu}g/mL$ in Buseoktae, $524.19{\mu}g/mL$ in Daewon, $422.71{\mu}g/mL$ in Wooram beans. Isoflavone contents of Buseoktae and Daewon were quite similar, relatively contents of Wooram beans were low. Total isoflavone contents of Buseoktae cheonggukjang (for business use) was $430.10{\mu}g/mL$ in A ($32^{\circ}C$, 96 h fermentation), $460.09{\mu}g/mL$ in B ($36{\sim}40^{\circ}C$, 30 h fermentation), $417.46{\mu}g/mL$ in C cheonggukjang($36{\sim}38^{\circ}C$, 72 h fermentation), B cheonggukjang was just a bit more than A, C cheonggukjang. The estimated response surfaces confirmed that the amount and time had significant effects on taste. The optimum condition of Buseoktae cheonggukjang taste was predicted to be 55.20 g addition at 2.92 min.

• Korean Journal of Ecology and Environment
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• v.47 no.4
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• pp.312-318
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• 2014

This study was conducted to establish models of filtrating rate and production of feces of a native freshwater bivalve, Anodonta woodiana, on removal organic matters in eutrophic waters. Among the applied shell size (4.3~15.5 cm), the filtrating rate and production of feces of Anodonta woodiana was $0.08{\sim}0.86L\;g^{-1}\;h^{-1}$ (average $0.24L\;g^{-1}\;h^{-1}$), $0.00{\sim}11.10mg\;g^{-1}\;h^{-1}$ (average $0.94mg\;g^{-1}\;h^{-1}$), respectively. In two different water current (high $48Lh^{-1}$, low $24Lh^{-1}$), the filtrating rate of Chl-a was $0.02{\sim}0.10L\;g^{-1}\;d^{-1}$ (average $0.05L\;g^{-1}\;d^{-1}$), $0.02{\sim}0.11L\;g^{-1}\;d^{-1}$ (average $0.07L\;g^{-1}\;d^{-1}$) and the removal rate was 65.4%, 82.1%, respectively. Response surface methodology, with a central composite design comprising 3 levels and 2 variables, was used to identify the optimal removal condition of shell length, water current and filtrating rate or feces production by bivalves. The optimum removal conditions were found that had optimized $6.21L\;mussel^{-1}\;d^{-1}$ at shell length 14.3~15.6 and water current $22{\sim}30Lh^{-1}$. The optimal conditions of production of feces ($4.2mg\;g^{-1}\;d^{-1}$) by freshwater mussels were shell length 14.3~16.3 cm and water current $36{\sim}44Lh^{-1}$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.894-902
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• 2016

The purpose of this study was to analyze the attributes considered as important by parents in the selection of laver for infants through conjoint analysis techniques. A total of 917 questionnaires were distributed in January 2016, of which 211 were completed (23.0%). Statistical data analyses were performed using SPSS/Win 21.0 for descriptive statistics and conjoint analysis. The conjoint design was applied to evaluate the hypothetical laver for infants. According to the analysis of attributes and levels of laver for infants, the relative importance of each attribute was follows: seasoning (26.55%), flavor (19.33%), texture (18.75%), oil (15.15%), size (10.61%), and certification (9.61%). The results of the conjoint analysis indicate that parents raising infants preferred laver with the characteristics of non-seasoning, general flavor, softness, half-size, organic certification, and perilla oil. The most preferred laver for infants gained a 53.7% potential market share from choice simulation compared with laver being sold. Using utility and relative importance, the laver market for infants was classified into two segments. As a result of market segmentation, parents of cluster 1 preferred the laver model being sold (soy seasoning) while parents of cluster 2 preferred the optimized laver model (non-seasoning).

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.4
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• pp.412-429
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• 2008

As the amount of electronic documents increases rapidly with the growth of the Internet, a parallel search engine capable of handling a large number of documents are becoming ever important. To implement a parallel search engine, we need to partition the inverted index and search through the partitioned index in parallel. There are two methods of partitioning the inverted index: 1) document-identifier based partitioning and 2) keyword-identifier based partitioning. However, each method alone has the following drawbacks. The former is convenient in inserting documents and has high throughput, but has poor performance for top h query processing. The latter has good performance for top-k query processing, but is inconvenient in inserting documents and has low throughput. In this paper, we propose a hybrid partitioning method to compensate for the drawback of each method. We design and implement a parallel search engine that supports the hybrid partitioning method using the Odysseus DBMS tightly coupled with information retrieval capability. We first introduce the architecture of the parallel search engine-Odysseus/parallel-OOSQL. We then show the effectiveness of the proposed system through systematic experiments. The experimental results show that the query processing time of the document-identifier based partitioning method is approximately inversely proportional to the number of blocks in the partition of the inverted index. The results also show that the keyword-identifier based partitioning method has good performance in top-k query processing. The proposed parallel search engine can be optimized for performance by customizing the methods of partitioning the inverted index according to the application environment. The Odysseus/parallel OOSQL parallel search engine is capable of indexing, storing, and querying 100 million web documents per node or tens of billions of web documents for the entire system.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1189-1196
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• 1998

Extraction conditions were optimized using response surface methodology for preparing high-quality ethanol extracts from cultivated Chrysanthemum petals. A fractional factorial design was applied to investigate effects of solvent ratio to sample $(X_1)$, ethanol concentration $(X_2)$ and extraction time $(X_3)$ at $60^{\circ}C$ on dependent variables of the extract properties, such as yellow color $(Y_1)$, carotenoids $(Y_2)$, soluble solids $(Y_3)$, phenolic compounds $(Y_4)$, electron donating ability $(Y_5)$, sensory color $(Y_6)$ and sensory aroma $(Y_7)$. Second-order models were employed to generate 3-dimensional response surfaces for dependent variables and their coefficients of determination $(R^2)$ were ranged from 0.8063 to 0.9963. Optimum extraction conditions for each variable were 115 mL/g, 97%, 18 hr in yellow color, 145 mL/g, 50%, 12 hr in carotenoids, 147 mL/g, 48%, 17 hr in soluble solids, 116 mL/g, 68%, 17 hr in phenolic compounds, 110 mL/g, 98%, 14 hr in electron donating ability, 101 mL/g, 48%, 54 hr in organoleptic color and 109 mL/g, 54%, 4 hr in organoleptic aroma, respectively. The range of optimum conditions at 16hr extraction for maximized characteristics of ethanol extracts was $103{\sim}122\;mL/g$ and $64{\sim}78%$. Predicted values at the optimum condition agreed with experimental values.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.8
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• pp.555-564
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• 2013

Innovative evolution in mobile devices along with recent spread of Tablet PCs and Smart Phones makes a new change not only in individual life but also in enterprise applications. Especially, in the case of medium-large mobile applications for large enterprises which generally takes more than 3 months of development periods, importance and complexity increase significantly. Generally Agile-methodology is used for a development process for the medium-large scale mobile applications, but some issues arise such as high dependency on skilled developers and lack of detail development directives. In this paper, S-MADP (Smart Mobile Application Development Process) is proposed to mitigate these issues. S-MADP is a service oriented development process extending a object-oriented development process, for medium-large scale mobile applications. S-MADP provides detail development directives for each activities during the entire process for defining services as server-based or client-based and providing the way of reuse of services. Also, in order to support various user interfaces, S-MADP provides detail UI development directives. To evaluate the performance of S-MADP, three mobile application development projects were conducted and the results were analyzed. The projects are 'TBS(TB Mobile Service) 3.0' in TB company, mobile app-store in TS company, and mobile groupware in TG group. As a result of the projects, S-MADP accounts for more detailed design information about 'Minimizing the use of resources', 'Service-based designing' and 'User interface optimized for mobile devices' which are needed to be largely considered for mobile application development environment when we compare with existing Agile-methodology. Therefore, it improves the usability, maintainability, efficiency of developed mobile applications. Through field tests, it is observed that S-MADP outperforms about 25% than a Agile-methodology in the aspect of the required man-month for developing a medium-large mobile application.

• Korean Journal of Optics and Photonics
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• v.20 no.5
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• pp.266-271
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• 2009

We designed a thermo-optic switch based on a directional coupler with not only a high extinction ratio but also significantly low power consumption. The switch operates by using the thermo-optic effect of the polymer which the refractive index changes by heating the electrode. If the electrode is not powered (OFF), the input light will be coupled completely to the other waveguide. When the electrode is powered at a certain level (ON), input light launched into the input waveguide will remain in that waveguide due to the lower index adjusted in the other waveguide. The switch based on the directional coupler was designed using the generalized extinction ratio curve and the lateral shift of the input waveguide. The coupling length is 1,610 ${\mu}m$ and the extinction ratios are -28 and -30 dB for ON and OFF states, respectively. The electrode structures were optimized by thermal analysis. The transported heat into the waveguide is increased, as the electrode width (w) is increased and the center distance between the electrode and the waveguide (d) is decreased. Also, because the heat generated in the electrode affects the other waveguide, the temperature difference between two waveguides is varied as the given w and d. There are specific conditions which have the maximum of the temperature difference. That of the temperature difference is increased as the width and the temperature of the electrode are increased. Especially, when the switch is designed using the condition with the maximum of the temperature difference for switching, the temperature of the electrode can be decreased. We expect this condition will be the novel method for the reduction of the power consumption in a thermo-optic switch.