• Journal of Wetlands Research
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• v.16 no.1
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• pp.61-72
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• 2014

To present a guideline on the construction and management of artificial wetlands for high biomass production, three emergent macrophytes (Phragmites australis, PA; Typha angustifolia, TA; and Zizania latifolia, ZL) were planted under two substrates conditions (general soil with and without moss peat) and two water levels (5 cm and 20 cm) and monitored for three years. ZL showed greater growth performance rather than the others not only at early growth phase in the first year [shoot height, 200 cm; above-ground dry weight (AGDW), 500 $g/m^2$] but also in the last year (ZL, 1,100 $g/m^2$; TA, 770 $g/m^2$; and PA, 450 $g/m^2$ of AGDW). ZL with rapid growth at the early growth phase was not affected by naturally introduced weeds, whereas slower and poorer growth of PA and TA at the early growth phase resulted in relatively higher introduction and establishment of natural weeds. In turn, such introduced weeds negatively contributed to the growth of PA and TA particularly under shallow water (5 cm) with the substrate condition including moss peat. We suggest a plant material with rapid and great growth at the early phase such as ZL for reducing possible negative influences by the natural weeds and wild animals for high biomass production in constructed wetlands. A pre-growing process in greenhouse prior to planting might be an useful option to raise the competitiveness of those species when planting PA and/or TA. In addition, we recommend that integrated weed management system with utilizing various options at the most appropriate timing must be applied for maintaining sustainable high biomass production at the artificial wetlands.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1236-1242
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• 2007

Sixty healthy growing pigs ($Duroc{\times}Landrace{\times}Yorkshire$ with an average BW of 21.4 kg) were used to determine the true digestible phosphorus (TDP) requirement of growing pigs on the basis of growth performance and serum biochemical indices. Pigs were assigned randomly to one of five dietary treatments (12 pigs/diet), representing five levels of TDP (0.16%, 0.20%, 0.23%, 0.26% and 0.39%). There were three replications per treatment, with four pigs (2 barrows and 2 gilts) in each replication (2 pigs/pen) A randomized-block design was used, with pen as the experimental unit. Experimental diets were formulated to provide the 5 TDP levels with a total calcium (Ca) to TDP ratio of 2:1, and offered to pigs at 5% BW for 28 d. The total Ca contents of the five diets were 0.33, 0.38, 0.45, 0.51 and 0.79%, respectively. During the 28-d experimental period, the ADG of pigs was affected by dietary TDP levels as described by Equation 1: y = $-809,532x^4+788,079x^3-276,250x^2+42,114x-1$,759; ($R^2$ = 0.99; p<0.01; y = ADG, g/d; x = dietary TDP, %). The feed:gain ratio for pigs was affected by dietary TDP levels as described by Equation 2: y = $3,651.1x^4-3,480.4x^3+1,183.8x^2-172.5x+10.9$ ($R^2$ = 0.99; p<0.01; y = feed:gain ratio; x = dietary TDP, %). Total P concentrations in serum were affected by dietary TDP levels as described by Equation 3: y = $-3,311.7x^4+3,342.7x^3-1,224.6x^2+195.6x-8.7$ ($R^2$ = 0.99; p<0.01; y = total serum P concentration and x = dietary TDP, %). The highest ADG (782 g/d), the lowest feed:gain ratio (1.07), and the highest total serum P concentration (3.1 mmol/L) were obtained when dietary TDP level was 0.34%. Collectively, these results indicate that the optimal TDP requirement of growing pigs is 0.34% of the diet (e.g., 5.1 g/day for a 30-kg pig that consumed 1.5 kg feed daily) at a total Ca to TDP ratio of 2:1.

• Journal of Life Science
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• v.19 no.5
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• pp.625-632
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• 2009

The purpose of this study was to examine the effect of exercise training on nitric oxide (NO) levels, mean arterial pressure (MAP), blood pressure (BP), and heart rate (HR) in college students. 5 subjects were randomly assigned to two experimental groups; an aerobic training group (ATG) and a resistance training group (RTG). In aerobic training, based on measured maximum oxygen consumption rate, 70% exercise intensity was applied and conducted for 60 min. In resistance training, 70% of 1-RM was performed for 90 min. Blood sampling was conducted 3 times during resting state, post-exercise, and after 30 minutes of recovery. The results are as followed. For the post training values of $VO_2max$, % body fat and MAP, there were significant differences in the ATG compared to pre training (p<0.05). However, there were no differences in the RTG between pre and post training. NO increased post training, during rest and at the end of exercise compared to pre training in the ATG (p<0.05). Also, the HR decreased in post training at the end of exercise (p<0.05), however, there were no significant differences in SBP and DBP between pre and post training in the ATG. The HR, SBP and DBP did not change at all in post training compared to pre training in the RTG. In conclusion, an increase in the production of Nitric Oxide (NO) concentration and $VO_2max$, decrease of body fat% and physiological variables (HR, BP, MAP) were shown to be more effective in aerobic training (AT) than resistance training (RT).

• Analytical Science and Technology
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• v.28 no.3
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• pp.196-203
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• 2015

Selenium species (inorganic selenium, selenoaminoacids, and selenoproteins) were analyzed using anion exchange and affinity chromatography, which were connected to ICP/MS for the blood serum of sows fed by seleniumfortified feed. The Anion Exchange PRP X-100 column was used for the analysis of inorganic selenium (Se⁴⁺ and Se⁶⁺) and selenoaminoacids. The HEP column was used to separate SelP from GPx+SeAlb in selenoproteins. A quantitative analysis was performed using the post-column isotope dilution technique. The lactating sows were divided into three groups and fed by selenium fortified feed (organic 0.3 mg/kg, 0.6 mg/kg and inorganic 0.6 mg/kg) for four weeks. The test groups showed increases in selenoaminoacids compared with the control group, except the inorganic feed group. There was no significant difference between the organic feed groups. All test groups showed increases in selenoproteins. In particular, SelP showed a large increase that was 1.5 times higher than the other proteins.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.473-481
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• 2018

Owing to its high protein secretion capacity, simple nutritional requirements, and GRAS (generally regarded as safe) status, Bacillus licheniformis is widely used as a host for the industrial production of enzymes, antibiotics, and peptides. However, as compared with its close relative Bacillus subtilis, little is known about the physiology and stress responses of B. licheniformis. To explore its temperature-stress metabolome, B. licheniformis strains ATCC 14580 and B186, with respective optimal growth temperatures of $42^{\circ}C$ and $50^{\circ}C$, were cultured at $42^{\circ}C$, $50^{\circ}C$, and $60^{\circ}C$ and their corresponding metabolic profiles were determined by gas chromatography/mass spectrometry and multivariate statistical analyses. It was found that with increased growth temperatures, the two B. licheniformis strains displayed elevated cellular levels of proline, glutamate, lysine, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, and octadecanoic acid, and decreased levels of glutamine and octadecenoic acid. Regulation of amino acid and fatty acid metabolism is likely to be associated with the evolution of protective biochemical mechanisms of B. licheniformis. Our results will help to optimize the industrial use of B. licheniformis and other important Bacillus species.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.3
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• pp.291-301
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• 2019

The purpose of this study is to develop HTE-STEAM program using natural disasters for high school students and to verify their attitude and satisfaction with STEAM. We developed the HTE-STEAM program utilizing natural disasters and tested the effectiveness of 243 students from G High School and N High School. For data analysis, a single group pretest and post response t-test were conducted to verify the effects on attitudes and satisfaction with STEAM. The research results are as follows. First, we developed STEAM education programs for high school students by selecting the topic of "natural disasters" in the area of earth science and flying drones as lifesaving drones. The six-hour program was designed to give students the experience to solve problems by applying essential knowledge related to natural disasters and drones, and what they learned in other situations. Second, there was a significant statistical test result in the t-test of the corresponding sample by the difference between the pre and post score of the STEAM attitude test (p <.05). The drone-based HTE-STEAM program had a significant improvement in the overall attitude toward STEAM education, which consists of seven subfactors. Third, in the HTE-STEAM satisfaction test, the average value of the lower job offer was 3.64 ~ 3.76, which showed a positive response overall. It is judged that the students' satisfaction is improved through the students' understanding of the problem situation and the design of creative convergence and production process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3777-3785
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• 2013

This study aimed to find out adolescents' media literacy in terms of reading, writing, and enjoying media or messages. For the purpose, we analyzed the data garnered from 1,036 students enrolled in 5 middle and 5 high schools, respectively. The analyses of the data are summarized as follows: First, mobile phone was most widely used among others, followed by TV, the Internet, mp3 player, computer or video game, radio, a video or DVD in the order. Second, a gender effect was significant in terms of the variety of activities with the Internet, mobile, and SNS: boys were more active in the use of the Internet while girls carried out more activities with a mobile phone and SNS media. Third, high school students showed more critical attitude towards information on the Website than did the middle school students. Fourth, Girls than boys, and high schoolers than middle schoolers, tended to be more active in the production of contents, self-expression, as well as participating in social and political issues online. Fifth, for the enjoyment experiences, time spent for games took up the most of the students' leisure activities, followed by watching TV and the use of the Internet. The findings of the study were discussed in light of media convergence, with implications for developing media literacy education for the youth.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.131-143
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• 2005

This study is performed to examine the meal management attitudes of housewives who had elementary schoolchildren in the remote rural areas(RA: n = 318, $37.2{\pm}0.3$ years of age) in comparison to those in their vicinity urban area(UA: n = 349, $36.9{\pm}0.2$ years of age) in the Chungnam province in Korea. The subjects were asked to fill out the questionnaire on their attitudes of meal management for their families. The results obtained in this study were as followings: (1) Most husbands of the subjects had a farming job in the RA while they had salaried workers in the UA(p<0.001). Education levels of both subjects and their husbands were lower in the RA than in the UA. Nuclear families were dominated by both groups, however single parent-family and step parent-family were more prevalent in the RA than in the UA. (2) in terms of ways of getting foods such as grains, meats, eggs, vegetables and fruits, the RA housewives relied more often on self-production than did the UA housewives(p<0.001). (3) The frequency of purchasing unprocessed foods was lower in the RA than in the UA(p<0.001). The RA housewives purchased the convenient foods such as instant noodles(p<0.05), ready to eatsoups(p<0.001), retort pouch foods(p<0.05) and instant teas(p<0.05) more frequently than did the UA housewives, while tuna, canned in oil(p<0.01), milk and their products(p<0.001), soybean products(p<0.001) and snacks(p<0.01) were purchased less often by the RA housewives. (4) Family members except housewives engaged more often in meal preparation in the RA than did those in the UA(p<0.001), which was more strongly observed for dinner. The time spent in preparing the dinner was shorter in the RA than in the UA(p<0.001). (5) The degrees of endeavor to provide the subjects' offspring with balanced meal(p<0.001) and nutrition education(p<0.01) were lower in the RA than in the UA. The RA housewives had more difficulty for performing meal management because of 'over work-related fatigue', 'insufficient money to purchase foods' and 'far distance from grocery' than the UA housewives(p<0.001). The RA housewives had lower score on nutritional knowledge(p<0.001) and wanted more strongly nutritional knowledge to improve the quality of family's meal than did the UA housewives(p<0.01). Therefore, the RA housewives had various problems regarding meal management such as 'over work related to fatigue', 'food-purchasing inconvenience', 'low economic status of family' and 'lack of nutritional knowledge'. As a consequence the RA housewives relied on cheap convenient foods more often in order to prepare the meal easily than did the UA housewives. These findings emphasize the need in the RA for nutrition education for housewives and a range of nutrition policies that focus upon the social and economic determinants of food choice within families to improve the nutritional status of the RA residents.

• Korean journal of food and cookery science
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• v.28 no.5
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• pp.559-567
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• 2012

The purpose of this study was to investigate the perceptions of the foodservice industry workers in regard to the use of seasonings and sweeteners in the restaurants. Questionnaires were distributed to 902 foodservice workers of various restaurants. Participants were questioned on their perceptions of both natural and artificial seasonings & sweeteners. Furthermore, they were asked to respond to questions regarding the need of public education and information about the use of seasonings and sweeteners, along with the demographic information. The results showed that 65.7% of respondents used both the artificial seasoning and artificial sweeteners, while 9.9% of respondents used only natural seasonings and sweeteners. The restaurant employees answered that they have tried to reduce the use of artificial seasonings and sweeteners(3.69/5 point). Some of the respondents reported that they have tried to increase the used of natural seasonings and sweeteners(3.54/5 point). There were significant differences in the respondents' perceptions and attitudes on the seasonings and sweeteners by the restaurant type(p<0.05). The respondents perceived the need for education on the safety of artificial seasonings and sweeteners(3.71/5point) and the production process of natural seasonings(3.75/5 point). There was no significant difference in the respondents' perceptions on the need for education of the seasonings and sweeteners by the restaurant type. The findings suggest that education regarding the use of artificial seasoning and artificial sweeteners, as well as cooking methods that use natural seasonings, is needed to reduce the use of artificial seasonings and sweeteners in restaurants.

• Journal of Engineering Education Research
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• v.4 no.1
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• pp.3-19
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• 2001

According to the acceleration of informationalization and technological renovation in new coming $21^c$, the material production elements like labor and capital as well as others which have been the resources of a country's competitive power are changing into formless knowledge-based assets like knowledge and technology. In order to meet these demands of this time, companies in developed countries are concentrating on competition and cooperation to obtain higher technology as a strategy towards becoming first-class countries in the world. Thus, the development program of human resources should focus on providing creative technical application ability. Especially, universities should develop knowledge, technology, creative problem-solving ability and realism acquired by various fields in industry where engineering is used and make it possible to perform practical tasks. As a plan for enforcement and management of this program, a certification program which evaluates the ability and accomplishments of the study of graduate students in order to manage the quality of education should be applied as soon as possible at the institute which trains engineers. In this study, among the accomplishment assessment which have been suggested as an alternative assessment method, portfolio assessment is introduced into the educational situation of engineering technological human resources to find a method of application.