• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.344-354
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• 2015

To investigate the effects of ionic liquid pretreatment on biomass, giant miscanthus was treated with 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]) and 1-butyl-3-methylimidazolium acetate ([Bmim][OAc]) at three temperature conditions ($90^{\circ}C$, $110^{\circ}C$, and $130^{\circ}C$). As temperature condition increased, yield of the cellulose-rich product (CP) was reduced from 87.2% to 67.6%, while yield of the ionic liquid lignin (ILL) increased from 2.2% to 9.9%. Compared to the ILL, CP had lower carbon contents and higher oxygen contents. Enzymatic hydrolysis of CPs showed that conversion ratio of CP treated with [Emim][OAc] at $110^{\circ}C$ was 56.7%, the highest digestibility. Thermogravimetric analysis indicated that the maximum degradation rate decreased as temperature condition increased. In addition, maximum degradation temperature of ILL treated with [Emim][OAc] ranged from 274 to $279^{\circ}C$ which was lower than that of ILL treated with [Bmim][OAc]. Analytical date for ${\beta}$-O-4 linkage frequency in the ILL revealed that ${\beta}$-O-4 linkage frequency in the ILL decreased as the temperature rose. Furthermore, the highest S/G ratio of the ILL was determined to ca. 1.2 obtained from [Bmim][OAc] treatment at $110^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1622-1633
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• 2002

The effects of tuna oil supplementation (0, 1, 2 and 3%) to pig diets on growth and carcass yield as well as meat quality were determined in 40 crossbred pigs. Animals were fattened from 30 to 90 kg of live-weight. Twenty-four hours after slaughter, following various early- and late-post mortem measurements, loin, backfat and belly were prepared from the carcasses. Bacon was produced from the belly part by curing and smoking. Neither performance (feed intake, daily gains, feed conversion efficiency) nor carcass quality (slaughter weight, dressing percentage, lean percentage, nutrient composition of the loin) were significantly affected by tuna oil supplementation. Tuna oil also had no clear effects on early- and late-post mortem meat quality traits, water-holding capacity and tenderness of the M. longissiumus dorsi (LD). Colour traits of LD and backfat, and backfat firmness were not significantly affected by tuna oil, either. However, there was a certain trend to elevated fat contents of LD (and bacon), but not of backfat, with increasing levels of tuna oil in feed. Pigs receiving elevated proportions of tuna oil expressed lower VLDL cholesterol and triglyceride concentrations in blood plasma, whereas the cholesterol content of LD, backfat and bacon did not reflect this trend. Effects of tuna oil on fatty acids in LD, backfat and bacon were often small in extent, except those concerning the long-chain polyunsaturated fatty acids. With 3% tuna oil in the diet, the contents of the particularly desired omega-3 fatty acids, C20:5 and C22:6, were 0.1 and 0.2 g/kg in LD. The corresponding values for backfat and bacon were 2.6 and 12.6 g/kg, and 1.3 and 9.2 g/kg, respectively. Tuna oil supplementation was associated with significant adverse effects on flavour and overall acceptance of bacon (not significant in LD although numerically the same trend was noted), but these effects on sensory ratings were limited in extent. Also shelf life of the products, determined as TBA value after different storage periods at $4^{\circ}C$ in LD, backfat and bacon, was significantly reduced. Overall, the present study suggests that omega-3 fatty acids may be enriched in pork by feeding tuna oil with few undesired side-effects, particularly those on sensory perception and shelf life, suggesting immediate consumption of the products is advisable. Most economically important traits (performance, slaughter and physical meat quality) remained unaffected.

• Journal of Digital Contents Society
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• v.12 no.1
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• pp.85-94
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• 2011

QoS(Quality of Service) is defined as "The collective effect of service performance which determines the degree of satisfaction of a user of the service" by ITU-T Rec. E.800. While the use of VoIP(Voice Over Internet Protocol) has been widely implemented, persistent problems with QoS are a very important sue which needs to be solved. This research is finding the assignment of VoIP QoS to deduct how to manage the control system and presenting the QoS control process and framework under NGN(Next Generation Network) environment. The trial framework is the modeling of the QoS measurement metrics, instrument, equipment, method of measurement, the series of cycle & the methodology about analysis of the result of measurement. This research underlines that the vulnerability of the VoIP protocol in relation to its QoS can be guaranteed when the product quality and management are controlled and measured systematically. Especially it's very important time to maintain the research about VoIP QoS measurement and control because the big conversion of new network technology paradigm is now spreading. In addition, when the proposed method is applied, it can reduce an overall delay and can contribute to improved service quality, in relation to signal, voice processing, filtering more effectively.

• Journal of Digital Convergence
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• v.15 no.4
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• pp.91-105
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• 2017

Korea is rapidly becoming a multicultural society in recent years, and the number of multicultural families in 2015 exceeds 3.5% and 800,000. Also, as international marriage rate exceeds 10% by 2016, the number of multicultural families is expected to steadily increase. This study is a design of a metadata application profile as part of the foundation for providing learning resources and content tailored to the needs and preferences of married immigrant women and multicultural family members who need to adapt to Korean society. In order to verify the necessity of the research, we conducted an in-depth interview by screening consumer groups, and analyzed the relevant international and Korean national standards as de-jure standards for the design of metadata standard profiles. Then, we analyzed the contents characteristics for multicultural members, and organized the necessary metadata elements into profiles. We defined the mandatory/optional conditions to reflect the needs of content providers. This study is meaningful in that the study analyzes the educational needs of married immigrant women and presents the necessary metadata standards to develop and service effective educational content, such as korean-to-korean conversion system, personalized learning contents recommendation service, and learning management system.

• Journal of Digital Contents Society
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• v.10 no.2
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• pp.199-207
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• 2009

The Q-switching the shutter or the different optical science element puts in within the laser light resonator and the storehouse departs from the within the resonator it loses the mortar and the reversal distribution which when is sufficient creates from within the active medium, opens the shutter instantaneously and it is to do to be made to emit with the light where the energy which is accumulated within the resonator is strong very. Like this Q-switching of laser resonator--It decreases factor increasing suddenly to make. To method of Laser Q-switching mechanical switching methods, electro-optic switching methods and switching by saturable absorber methods, acousto-optic switching method etc. 4 kind are being used on a large scale. In these people the conversion which is electric in compliance with the effect which is electrooptics is widely being used the Q-switching pulse of short pulse width because being it will be able to create. Consequently, Pockel cell where it has the quality of electrooptics effect) the Q-it is become known that it is suitable it uses with switch. From the research which it sees FET and one-chip microprocessor where it is a switching element and pulse transfomer to plan and produce pockel cell Q-switch driving gears, pulse style Nd: It applied in YAG Laser system and it investigated and researched the operating characteristic of the Q-switch. Also, the Q-switch leads and Nd where it is output: YAG with forecast in compliance with a theoretical calculation it comes to buy laser beam side politics it compared and laser beam qualities which had become Q-switching it analyzed.

• Journal of The Korean Association For Science Education
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• v.37 no.5
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• pp.799-812
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• 2017

Energy as a powerful and unifying concept to understand natural world has been regarded as one of the key concepts of the science curricula in many countries. However, concerning learning and teaching of energy, various difficulties have been reported widely. This study aimed at analyzing and comparing science curricula of Korea, the U.S., England, and Singapore regarding energy to identify the potential issues for energy curriculum in the future. 2015 revised Korean science curriculum, Next Generation Science Standards of the U.S., Science programmes of study of England, and the Science syllabus of Singapore were compared based on six basic elements of the concept of energy: energy form, energy resource, energy transfer, energy transformation, energy conservation, and energy dissipation. Achievement criteria that include energy were extracted from all curricula and categorized into the six elements. The frequency and distribution of the six elements in the four curricula were compared in terms of school levels and disciplinary areas. Contents of six energy elements were also compared. Though all curricula emphasized energy as a key science concept, we found many differences in the degree of emphasis of basic ideas and specific contents and approaches. Korean curriculum is characterized by 1) high frequency concerning energy form among the elements of the concept of energy, 2) introducing energy forms of unclear meaning, which are not linked with other physical quantities, 3) emphasis on energy conversion in comparison of energy transfer, 4) focusing on mechanical energy conservation instead of more general energy conservation, and 5) absence of the concept of 'system' concerning energy. Issues for energy curriculum development were discussed.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.34-40
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• 2014

Mesoporous SAPO-34 catalyst was successfully synthesized by the hydrothermal method using carbon nanotube (CNT) as a secondary template. The effects of CNT contents (0.5, 1.5, 2.5, and 4.5 mol%) on catalytic performances were investigated. The synthesized catalysts were characterized with XRD, SEM, nitrogen physisorption isotherm and $NH_3$-TPD. Among the synthesized catalysts, SAPO-34 catalyst prepared by the addition of 1.5 mol% CNT (1.5C-SAPO-34) observed not only the largest amounts of mesopore volume but also acid sites. However, the mesopore volume was relatively decreased by further increasing of CNT contents due to the formation of small crystalline. The catalytic lifetime and the selectivity of light olefins ($C_2{\sim}C_4$) were examined for the dimethyl ether to olefins reaction. As a result, the 1.5C-SAPO-34 catalyst showed an improvement of ca. 36% in a catalytic lifetime and a better selectivity to light olefins as compared with the general SAPO-34 catalyst.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.347-358
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• 2021

The purpose of this study was to investigate the stage of concern and use level of early childhood teachers' STEAM, and to find out whether there is a difference in the stage of concern according to individual teachers' variables. The subjects were 242 teachers in charge of 3-5 years old kindergarten and daycare center in G city. The research tool was the stages of concern questionnaire (SoCQ). The collected data were converted to relative intensity by applying percentile conversion chart in the guidelines, and this was expressed as a concern profile graph, and t-test and ANOVA were performed to find out the difference in concern according to teacher's background variables. The research results are as follows. First, the stage of concern in early childhood teachers' STEAM was identified as a critical non-user profile. Second, the stage of concern in the teacher's STEAM was judged as a person who did not use, or was implemented for less than 2 years, and was a non-user or a novice. In addition, it was found that most of the teachers did not receive formal education for STEAM. third. There were differences in the educational background, career, current execution status of teachers, whether or not to take related courses in pre-service teacher education, and whether to plan for future implementation. And there were no differences in the majors and institution types of teachers. Based on these results, a support plan for changing the stage of concern of teachers about STEAM and improving the level of use was suggested.

• Korean Journal of Poultry Science
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• v.50 no.2
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• pp.101-108
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• 2023

This study was conducted to investigate the appropriate levels of crude protein (CP) and phytase in the diet of broiler chicks in order to reduce nitrogen and phosphorus contents in feces while maintaining performance of broilers. Six hundred forty-eight 1-day-old male broilers (41.9±0.91 g) had a total of 3 × 3 complex factor of 3 levels of CP (22%, 21%, 20%) and 3 levels of phytase (1,000, 800, 500 FTU/kg) in the diet. Divided into 9 treatments, 4 replications per treatment, 18 birds per replication, were completely randomly assigned and reared in a metabolic cage for 7 days. Seven-day-old body weight (BW) and body weight gain (BWG) of broilers were significantly lower at CP 20% treatment (P<0.05), and feed conversion ratio (FCR) was significantly lower at CP 21% and phytase 800 FTU/kg treatment (P<0.05). Nitrogen and phosphorus contents in chicken excreta were significantly lower in CP 20% and phytase 500 FTU/kg treatment, respectively (P<0.05). Interactions between CP and phytase in the feed were shown for nitrogen and phosphorus in feces (P<0.05). In conclusion, considering the broiler performance and excretion contents of nitrogen and phosphorus, it is thought that CP and phytase levels of broiler chicks diet can be reduced by 21% and 800 FTU/kg, respectively.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.25-30
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• 1985

In order to observe an effect of the components of rice straw on the utilization of nutrient in chicks, the rice straw of 100g were digested in 800$m\ell$ of distilled water or 0.25N NaClO$_2$ at 135 C and in the pressure of 3.2kg/$\textrm{cm}^2$ by autoclave during 30, 60 and 120 minutes (water or NaClO$_2$-30, 60 and 120- RS). The contents of neutral detergent fiber(NDF), acid detergent fiber (ADF) and lignin were analysed in the washed and dried rice straw meal. Hatched single comb white Leghorn male chicks were fed with a commercial chick mash for the first 10 days and five kinds of experimetal diets for the next 8 days which contained 17.0% of wheat bran (basal), cellulose(cotton meal), nontreated RS, water-30-RS and NaClO$_2$ 30-RS, respectively. The water-30, 60 and 120-RS baa leased 9.7, 12.1 and 13.3% of dry matter, respectively, while NaClO$_2$-30-RS had similar contents of dry matter loss with those of water-30-RS, and NaClO$_2$-60 and 120-RS had tossed 1.5 times of dry matter comparing with those of water-60 and 120-RS, respectively. And the dry matter loss of the water-RS or NaClO$_2$-RS was mainly originated front the extractable cell contents and hemicellulose of the non-treated RS. Birds fed water-30-RS diets had higher body weight gain and lower feed conversion than those of birds fed non-treated and NaClO$_2$-30-RS diets during 8 days of experimental feeding. Also nitrogen balance and retention rate of birds fed water -30-RS was higher comparing with those of birds non-treated and NaClO$_2$-30-RS. And digestibility of crude fat had been shown a highering trend in birds water-30-RS. The rate of metabolizable energy (MEn) to gross energy (GE) of birds fed non-treated RS, water-30-RS and NaClO$_2$30-RS diets were 71.9, 72.9 and 70.4%, respectively, and energy intake per metaboic body size (kg 0.75) were reached to 307.3, 296.2 and 291.4 kcal per day, respectively. And daily protein retention per kg 0.75 were 1.647, 1.969 and 1.560g, respectively. Then 30.56kcal of MEn required for 1 g of protein retention in birds fed water-30-RS, which was lower thu 36.90 and 37.56 kcal of birds fed non-treated and NaClO$_2$-30- RS, respectively. The results seems to indicate that non-treated rice straw had a substance or characters which affect the energy unilization or protein retention of diets and which will be eliminated by boiling in water.