• Title/Summary/Keyword: breaking efficiency

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Microwave Irradiation as a Way to Reutilize the Recovered Struvite Slurry and to Enhance System Performance (회수된 MAP 슬러리의 재이용과 공정효율 향상을 위한 도구로서의 극초단파 조사)

  • Cho, Joon-Hee;Lee, Jin-Eui;Ra, Chang-Six
    • Journal of Animal Science and Technology
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    • v.51 no.4
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    • pp.337-342
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    • 2009
  • The feasibility of reutilization of magnesium ammonium phosphate (MAP) or struvite slurry recovered from the process through microwave irradiation was studied in this experiment. For this purpose, 4 different operations were performed with or without Mg source addition and different levels of MAP recycled in a batch reactor. Dissolution rate of MAP, ${NH_4}^+$ elimination pattern and physicochemical changes of MAP during microwave irradiation were also studied. The result showed that only 33% orthophosphate ($PO_4-P$) and 27% $NH_4-N$ removal occurred without adding any external Mg source (run A), whereas 87% $PO_4-P$ and 40% $NH_4-N$ removed when 1.0 M ratio of $MgCl_2$ (run B) was added based on $PO_4-P$ in influent. Although the addition of 1.0 molar ratio of microwave irradiated MAP (Run C) removed lower $PO_4-P$ and $NH_4-N$ than 1.0 M $MgCl_2$ (run B), $PO_4-P$ removal was double when compared with no Mg addition (run A). Addition of half MAP and half $MgCl_2$ (run D) showed the similar removal efficiency (88% $PO_4-P$ and 35% $NH_4-N$) with sole $MgCl_2$ addition (run B). Based on these results, the reutilization of MAP irradiated by microwave would be a feasible way to enhance the removal efficiencies of N and P, as well as curtail the Mg chemical usage. Track study showed that $NH_4-N$ gradually increased at initial stage of microwave irradiation of MAP, and then started eliminating from liquor as temperature increased over $45^{\circ}C$. Dissolution rate of ${PO_4}^{-3}$ during microwave irradiation was proportional to the initial MAP concentration, having $0.0091x^{0.6373}$ mg/sec. It was found from the scanning electron microscope (SEM) study that physical structure of MAP crystal started breaking down into small cube granules within very short time by electromagnetic vibration force during microwave irradiation and then gradually melted down into solution.

Preparation and Characteristics of Surimi Gel with Red-tanner Crab (Chionoecetes japonicus ) Paste (게 페이스트 첨가 연제품의 제조 및 특성)

  • Kim, Hye-Suk;Choi, Seung-Geal;Park, Chan-Ho;Han, Byung-Wook;Yang, Soo-Kyeong;Kang, Kyung-Tae;Oh, Hyeon-Seok;Heu, Min-Soo;Kim, Jin-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.7
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    • pp.1103-1108
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    • 2005
  • A new type of surimi gel was prepared by adding the crab paste to the original Alaska pollock surimi, and its characteristics were determined. With increased addition of crab paste to the surimi, moisture $(81.3\;to\;79.1\%)$ and protein content $(12.2\;to\;11.6\%)$ of surimi gels slightly decreased while ash content increased compared to commercial surimi gel. Color values of surimi gels were decreased in lightness (L value, 67.3 to 63.5) but increased in redness (a value, -3.5 to 7.14). Thus, crab paste-added surimi gel was a little darked reddish product. Maximum values of breaking force and deformation of $10\%$ added surimi gel were 568g and 13.1mm, respectively. Sensory scores on color and flavor increased according to the increasing of additional ratios, whereas texture scores was maximum at $10\%$ added surimi gel. From the results of physical properties and sensory evaluation, desirable additional ratio was $10\%$. Total amino acid content (11,435 mg/100g) of $10\%$ added surimi gel was approximately $5\%$ less than non-added surimi gel, and major amino acids were aspartic acids, glutamic acid, leucine and lysine. Exceptionally, cysteine content of $10\%$ added surimi gel was 2 times higher than control (surimi gel without crab paste). Calcium and phosphorus contents of $10\%$ crab paste-added surimi gel were 172:4mg/l00g and 234.6 mg/100g, respectively, and their ratio (1:1.4) was in the optimal range in the body absorbtion efficiency.

A Study on the Influence of IT Education Service Quality on Educational Satisfaction, Work Application Intention, and Recommendation Intention: Focusing on the Moderating Effects of Learner Position and Participation Motivation (IT교육 서비스품질이 교육만족도, 현업적용의도 및 추천의도에 미치는 영향에 관한 연구: 학습자 직위 및 참여동기의 조절효과를 중심으로)

  • Kang, Ryeo-Eun;Yang, Sung-Byung
    • Journal of Intelligence and Information Systems
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    • v.23 no.4
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    • pp.169-196
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    • 2017
  • The fourth industrial revolution represents a revolutionary change in the business environment and its ecosystem, which is a fusion of Information Technology (IT) and other industries. In line with these recent changes, the Ministry of Employment and Labor of South Korea announced 'the Fourth Industrial Revolution Leader Training Program,' which includes five key support areas such as (1) smart manufacturing, (2) Internet of Things (IoT), (3) big data including Artificial Intelligence (AI), (4) information security, and (5) bio innovation. Based on this program, we can get a glimpse of the South Korean government's efforts and willingness to emit leading human resource with advanced IT knowledge in various fusion technology-related and newly emerging industries. On the other hand, in order to nurture excellent IT manpower in preparation for the fourth industrial revolution, the role of educational institutions capable of providing high quality IT education services is most of importance. However, these days, most IT educational institutions have had difficulties in providing customized IT education services that meet the needs of consumers (i.e., learners), without breaking away from the traditional framework of providing supplier-oriented education services. From previous studies, it has been found that the provision of customized education services centered on learners leads to high satisfaction of learners, and that higher satisfaction increases not only task performance and the possibility of business application but also learners' recommendation intention. However, since research has not yet been conducted in a comprehensive way that consider both antecedent and consequent factors of the learner's satisfaction, more empirical research on this is highly desirable. With the advent of the fourth industrial revolution, a rising interest in various convergence technologies utilizing information technology (IT) has brought with the growing realization of the important role played by IT-related education services. However, research on the role of IT education service quality in the context of IT education is relatively scarce in spite of the fact that research on general education service quality and satisfaction has been actively conducted in various contexts. In this study, therefore, the five dimensions of IT education service quality (i.e., tangibles, reliability, responsiveness, assurance, and empathy) are derived from the context of IT education, based on the SERVPERF model and related previous studies. In addition, the effects of these detailed IT education service quality factors on learners' educational satisfaction and their work application/recommendation intentions are examined. Furthermore, the moderating roles of learner position (i.e., practitioner group vs. manager group) and participation motivation (i.e., voluntary participation vs. involuntary participation) in relationships between IT education service quality factors and learners' educational satisfaction, work application intention, and recommendation intention are also investigated. In an analysis using the structural equation model (SEM) technique based on a questionnaire given to 203 participants of IT education programs in an 'M' IT educational institution in Seoul, South Korea, tangibles, reliability, and assurance were found to have a significant effect on educational satisfaction. This educational satisfaction was found to have a significant effect on both work application intention and recommendation intention. Moreover, it was discovered that learner position and participation motivation have a partial moderating impact on the relationship between IT education service quality factors and educational satisfaction. This study holds academic implications in that it is one of the first studies to apply the SERVPERF model (rather than the SERVQUAL model, which has been widely adopted by prior studies) is to demonstrate the influence of IT education service quality on learners' educational satisfaction, work application intention, and recommendation intention in an IT education environment. The results of this study are expected to provide practical guidance for IT education service providers who wish to enhance learners' educational satisfaction and service management efficiency.