• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.960-968
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• 2003

A bacterial isolate showing a strong endochitosanase activity was isolated from soil and then characterized. The isolate was identified and designated as Bacillus cereus P16, based on morphological and biochemical properties, assimilation tests, cellular fatty acids pattern, along with 16S rRNA gene sequence. The optimized medium for producing extracellular chitosanase in a batch culture contained 1% tryptone, 0.5% chitosan, and 1% NaCl (pH 7.0). Powder chitosan and tryptone served the best as carbon and nitrogen sources, respectively, for the chitosanase production. Chitosanase activity was the highest when culture was completed at $37^{\circ}C$ among various temperatures ($20-42^{\circ}C$) tested in a shaking incubator (200 rpm). The levels of chitosanase activity in the culture fluid were 2.0 U/ml and 3.8 U/ml, respectively, when incubated in a flask for 60 h and in a jar fermenter for 24 h. The culture supernatant showed a strong liquefying activity on the soluble chitosan. The viscosity of 1% chitosan solution, that was incubated with the culture supernatant, was rapidly decreased, suggesting the secretion of endochitosanolytic enzymes by P16. The culture fluid revealed six endo-type chitosanase isozymes, two major (38 and 45 kD), and four minor (54, 65, 82, and 96 kD) forms by staining profile. The crude enzymes were very stable, and full activity was maintained for 4 weeks at $4^{\circ}C\;or\;-20^{\circ}C$ in the culture supernatant, suggesting a highly desirable stability rate for making an industrial application of the crude enzymes. The supernatant also cleaved the insoluble chitosan powder, but the hydrolysis rate was much lower. The enzymic degradation products of chitosan contained $(GlcN)_n$ (n=2-8). The concentration of chitosan in the reaction mixture of the crude enzyme affected the chitooligosaccharides composition of the hydrolysis products. When the higher concentration of chitosan was used, the higher degree of polymerized chitooligosaccharides were produced. By comparison with other commercial chitosanase preparations, P16 was indeed found to be a valuable enzyme source for industrial production of chitooligosaccharides from chitosan.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.1-11
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• 2014

This study was carried out to investigate nutritional and physiologically active characterizations of sikhae and the seasoned products from the sea squirt Halocynthia roretzi. The total taste values of sikhae fermented for 4 and 5 days were 10.9 and 15.4, respectively, which was lower than for commercially seasoned sea squirts. The sikhaes contained mostly glutamic and aspartic acids. The total amino acid contents of sikhaes fermented for 4 and 5 days were 5.5 and 6.0 g/100 g, respectively, which were lower than those of commercial seasoned-sea squirts or similar. An amount of 100 g of sikhae and its seasoned products contained P, K, Mg and Fe, and these minerals, which are deemed good for our health, were at 10% above the recommended daily requirements. The functional properties of sikhae fermented for 4 and 5 days were as follows: for ACE inhibiting activity, 69 and 69.5%, respectively; for antioxidative activity, 28.9 and 29.3%, respectively; for xanthine oxidase inhibitory activity, 52.8 and 53.1%, respectively; and for ${\alpha}$-glucosidase inhibitory activity, 2.4 and 1.4%, respectively. Antimicrobial activity of the 5 day fermented sikhae against Vibrio parahaemolyticus and Staphyloccus aureus was detected in 8 mm and in 7 mm against Escherichia coli.

• Journal of the Korean Wood Science and Technology
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• v.41 no.1
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• pp.77-86
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• 2013

This research was carried out to evaluate and raise the energy efficiency of wood frame house. The commercial solution program CE3 (Construction Energy Efficiency Evaluation) was used for simulating the energy consumption in the single-family wood frame house. The results showed that the annual heating energy demand of the house was 160 kWh per 1 $m^2$ floor area. In order to decrease the heating energy demand, the following energy efficiency methods were applied to the simulation : a) simplification of building shape, b) decrease of windows area, c) application of high performance windows (with low thermal transmittance) and d) application of heat recovery ventilator. In case of replacement of the windows with high performance one with thermal transmittance 1 $W/m^2{\cdot}K$, the lowest heating demand of 80 $kWh/m^2{\cdot}a$ was obtained. The best combination of methods, application of high performance windows and heat recovery ventilator, showed heating energy demand 34.5 $kWh/m^2{\cdot}a$.

• Food Science and Preservation
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• v.17 no.1
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• pp.16-22
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• 2010

To maintain the storage quality of agricultural products, temperature uniformity during cold storage, which is affected by fan flow rate and product arrangement, is important. We simulated and validated a CFD (Computational Fluid Dynamics) model that can predict both airflow and temperature distribution in a cold storage environment. Computations were based on a commercial code (FLUENT 6.2) and two turbulence models. The standard k-$\varepsilon$ model and the Reynolds stress model (RSM) were chosen to improve the accuracy of CFD prediction. To obtain comparative data, the temperature distribution and velocity vector profiles were measured in a full-scale cold storage facility and in a 1/5 scale model. The agricultural products domain in cold storage was modeled as porous for economical computation. The RSM prediction showed good agreement with experimental data. In addition, temperature distribution was simulated in the cold storage rooms to estimate the uniformity of temperature distribution using the validated model.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.177-183
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• 2010

Bum-type $CO_2$ generators are widely used in greenhouses for the purpose of $CO_2$ supply for photosynthesis and greenhouse heating. However harmful gases included in the air might give severe effects on the plant growth. For investigating the possible emission of harmful gases from commercial bum-type $CO_2$ generators, we carried out the analysis of the harmful by-products (NO, NOx, $NO_2$, CO, and VOCs) and $CO_2$ caused by using a bum-type $CO_2$ generator in greenhouses. And the harmful by-products from different type of fuels such as kerosene, LPG, and LNG were quantified. In order to minimize the uncertainties from a $CO_2$ generator, 4 different $CO_2$ generators were utilized in four plastic greenhouses and a glasshouse located at different places during the experimental works. The results showed that the concentration of NOx is proportional to $CO_2$ concentration. Levels of harmful gases in the most of greenhouses, where the new bum-type $CO_2$ generators were installed, were lower than 1.0 ppm when $CO_2$ concentration was set at 1,000 ppm. In case of LNG combustion, the concentration of CO reached out up to 300 ppm and pre-treatment for CO reduction, such as the adsorption process, would be inevitable to abate the adverse effects on plant growth.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.876-883
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• 2015

Han-green project, which pursues Korean style post and beam timber house with traditional construction technique of Han-ok, has been carried out in KFRI (Korea Forest Research Institute) since 2006. Recently, the improvement of its building energy performance was studied with energy-saving elements. This study was conducted to provide the insulation details of building envelopes in a post-beam timber house for recent enhanced insulation standards and following effect on building energy performance. The level of thermal transmittance (U-value) values of building envelopes was composed of two stages: present Korean insulation standards and passive house. To evaluate building energy performance, the building airtightness values of two stages was ACH50 = $3.0h^{-1}$ for common domestic timber house constructed recently, and ACH50 = $0.6h^{-1}$ for passive house. Consequently, four cases of the building energy performance according to the combination of U-value with airtightness were evaluated. The test house for evaluation was located in Seoul and its energy performance was evaluated with CE3 commercial building energy simulation program. The result showed that enhanced insulation from level I to II reduced $14kWh/(m^2{\cdot}a)$ of annual heating energy demand regardless of airtightness.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1287-1293
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• 2016

The objectives of this experiment was to evaluate the subsequent growth and organ weights, blood profiles and cecal microbiota of broiler chicks fed pre-starter diets containing fermented soybean meal products during early phase. A total of nine hundred 1-d-old chicks were randomly assigned into six groups with six replicates of 25 chicks each. The chicks were fed control pre-starter diet with dehulled soybean meal (SBM) or one of five experimental diets containing fermented SBM products (Bacillus fermented SBM [BF-SBM], yeast by product and Bacillus fermented SBM [YBF-SBM]; Lactobacillus fermented SBM 1 [LF-SBM 1]; Lactobacillus fermented SBM 2 [LF-SBM 2]) or soy protein concentrate (SPC) for 7 d after hatching, followed by 4 wk feeding of commercial diets without fermented SBMs or SPC. The fermented SBMs and SPC were substituted at the expense of dehulled SBM at 3% level on fresh weight basis. The body weight (BW) during the starter period was not affected by dietary treatments, but BW at 14 d onwards was significantly higher (p<0.05) in chicks that had been fed BF-SBM and YBF-SBM during the early phase compared with the control group. The feed intake during grower and finisher phases was not affected (p>0.05) by dietary treatments. During total rearing period, the daily weight gains in six groups were 52.0 (control), 57.7 (BF-SBM), 58.5 (YBF-SBM), 52.0 (LF-SBM 1), 56.7 (LF-SBM 2), and 53.3 g/d (SPC), respectively. The daily weight gain in chicks fed diet containing BF-SBM, YBF-SBM, and LF-SBM 2 were significantly higher values (p<0.001) than that of the control group. Chicks fed BF-SBM, YBF-SBM, and LF-SBM 2 had significantly lower (p<0.01) feed conversion ratio compared with the control group. There were no significant differences in the relative weight of various organs and blood profiles among groups. Cecal microbiota was altered by dietary treatments. At 35 d, chicks fed on the pre-starter diets containing BF-SBM and YBF-SBM had significantly increased (p<0.001) lactic acid bacteria, but lowered Coli-form bacteria in cecal contents compared with those fed the control diet. The number of Bacillus spp. was higher (p<0.001) in all groups except for LF-SBM 1 compared with control diet-fed chicks. At 7 d, jejunal villi were significantly lengthened (p<0.001) in chicks fed the fermented SBMs vs control diet. Collectively, the results indicate that feeding of fermented SBMs during early phase are beneficial to the subsequent growth performance in broiler chicks. BF-SBM and YBF-SBM showed superior overall growth performance as compared with unfermented SBM and SPC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.418-429
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• 2012

In this study we surveyed the packaging preferences of consumers for Korean rice cakes as current commercial products in Korea. The questionnaire was developed from a preliminary investigation of typical rice cake packaging patterns and sent to 2332 residents in Korea by random sampling mail. The questionnaire contained questions on the preferences of interior design in packaging, opening methods, individually separated types, printing position, packaging methods, and packaging materials such as paper and plastic. There were responses from 304 residents. The collected data was analyzed by an SPSS package program. Most of the packaging used for Korean rice cakes was plastic (58.9%) which was used for packaging materials and stretch wrap (42.9%) as packing methods. The results showed the preference was the perforated line type used by hand for opening a packaging and interior packaging design with 2~3 partitions. Most respondents expressed an interest in using individual packaging and having printing directly on the packaging. Also, the respondents preferred the packaging design that let them see the contents of a package. Based on the results of the questionnaire, this paper suggested that most consumers would prefer to choose a packaging system with a partition design in a plastic container, individually separated products, and a transparent container for Korean rice cakes. The results of packaging preferences could provide important information for suitable packaging development for Korean rice cakes. Further research should be conducted to improve the shelf life of Korean rice cakes with functional packaging systems such as modified atmosphere packaging or anti-microbial packaging.

• The Journal of the Korea Contents Association
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• v.5 no.2
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• pp.69-77
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• 2005

This study made a comparison of two different websites in characteristics of their users and advertising effects. Both websites have the same contents but in different forms. Especially this study examined the technographic, demographic and psychographic characteristics of users of an website which offers services only online and another website which offers services both online and offline. Also the advertising effects of both websites were studied. The analysis of the data was done by SPSSWIN, mainly $x^2$ and t-test. In addition, the data was collected online. The website, feelpost.com collected total 432 copies, and cardkorea.com collected 210 copies. Also among those collected copies, the ones from people in the 20's were selected again in order to rule out the special characters that both websites have in their users age group. Finally 308 copies were selected for the analysis. In result, it was proved that the users of both websites have a very similar lifestyle. Also there was only a little difference in the users' values and social consciousness. Regarding the advertising effect, Feelpost got the highest score in usefulness while Cardkorea got the highest score in positive acceptance of new products. Regarding the attitude toward advertisements and products, the advertising preference and brand preference was higher in Feelpost than in Cardkorea.

• Journal of Distribution Science
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• v.12 no.12
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• pp.55-63
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• 2014

Purpose - In urban regeneration projects, considerations for rejuvenating traditional public markets are becoming increasingly important. That is because the traditional market is not just a commercial space but also a living center for local people's existence. Cultural contents like these are invaluable assets in the contemporary economy. However, traditional markets are gradually declining because of changes in distribution systems and consumer lifestyles. New distribution systems such as modern distribution markets, home shopping, and online shopping malls made traditional markets less competitive. Further, traditional markets have not been able to adapt to the changing consumption styles of younger generations. Some say that it is a natural phenomenon that cannot be stopped. However, traditional markets are not just another distribution system but also a valuable resource that encapsulates the local people's tradition and history. Thus, a revitalization strategy for traditional public markets has become an urgent task in contemporary urban regeneration projects. This study aimed to find ways to activate traditional public markets by making it a community landmark based on visual merchandising perspectives. Research design and methodology - This study focused on analyzing Granville Island (Vancouver, Canada) as a role-model project for rejuvenating the traditional market. It investigated Granville Island both with walk-through evaluation and literature reviews. Results - We found that it has been developed not only to improve visual aspects, but also to promote cultural contents with high value added. For example, the developers maintained the visual elements that tell the original history of the site as an industrial factory. The renewal project had a balance between improving the outer look and creating attractive contents. The following are the merits of Granville Island that Korean traditional markets should note. First, they kept the whole area clean and hygienic. Second, merchants are well educated, business-savvy, and consumer-oriented. Third, the area's total environmental designs were done by professionals of a high caliber. Fourth, the city government and the merchants'association were collaborating well in their efforts to accommodate the changing needs of consumers. Conclusions - This study made the following suggestions as a conclusion. First, it will be a very powerful tool to rejuvenate the traditional market if we can discover unique cultural resources and develop them as cultural products, experiences, and events. Consumers of the 21st century have a strong tendency to consume not only material products, but also the experiences and memories attached to them. Second, in order to maintain the unique characteristics of traditional markets, fostering the viability of the merchants' association and local residents' society would be essential. Third, it is necessary to make the traditional market into a cultural place not only for the shopping patronage of local residents, but also for attracting tourists to increase sales. Finally, professional management and design approaches are needed in order to make the traditional market a pleasant space from a visual merchandising standpoint.