• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.106-111
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• 2012

Drying characteristic of high moisture coal using a 5 kg/hr bench scale flash dryer was investigated. Moisture content and heating value of raw coal as received basis were 29.74 wt% and 4,270 kcal/kg, respectively. Gas inlet temperature and gas inlet flow rate were $400{\sim}600^{\circ}C$ and 10~20 m/sec, respectively. The raw coal was ground and classified to the particle size range of $100{\sim}2,000{\mu}m$. The moisture removal rate of raw coal was dramatically increased with increasing gas inlet temperature and decreasing gas inlet flow rate. The heating value of dried coal was increased to 5,100~5,900 kcal/kg. To examine the chemical change on the surface of high moisture coal during flash drying process, FT-IR spectral analysis was carried out. As a result, major changes in hydroxyl, carboxyl and carbonyl peak was confirmed.

• Journal of the Korean Chemical Society
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• v.33 no.3
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• pp.295-303
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• 1989

Tetradentate Schiff base cobalt(II) complex; Co(SND) and Co(SOPD) were synthesized, and these complexes were allowed to react with dry oxygen to form oxygen adducts cobalt(III) complexes such as $[Co(SND)(Py)]_2O_2$ and $[Co(SOPD)(Py)]_2O_2$ in pyridine. These complexes have been identified by IR specta, T.G.A., magnetic susceptibilities measurements and elemental analysis. It has been found that the oxygen adducts coblat(III) complexes have hexacoordinated octahedral configuration with tetradentate Schiff base cobalt(II), pyridine and oxygen, and the mole ratio of oxygen to cobalt(II) complexes are 1;2. The redox reaction processes of $Co(SND)(Py)_2$ and $Co(SOPD)(Py)_2$ complexes were investigated by cyclic voltammetry with glassy carbon electrode in 0.1M TEAP pyridine. The result of redox reaction processes of Co(III)/Co(II) and Co(II)/Co(I) for $Co(SND)(Py)_2$ and $Co(SOPD)(Py)_2$ complexes are reversible or quasi reversible process but oxygen adducts complexes are irreversible processes. Redox process for oxygen of oxygen adducts complexes was quasi reversible and redox range of potential was $E_{pc}\;=\;-0.96{\sim}-1.03V$ and $E_{pa}\;=\;-0.78{\sim}-0.80V.$

• Korean journal of applied entomology
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• v.38 no.2
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• pp.157-164
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• 1999

A tarsonemid mite. Stet~rotc~r.sot~rrrs~puin.sk i Smiley 1967. is an important rice pest in major rice producing countries of Thailand. Philippine. China, and Taiwan. S. spinki was found first time in Korea from rice grown in environment controlled greenhouse. Rice fed by the mite showed damage symptoms of deformed panicles and inflorescence, lesions on the inner surface of leaf sheath, and browning of rice hulls. Females of S. .spi~lkwi as 263.0 pni (246.5-284.6f 12.2) in body length and 92.4 pm (79.5- 104.9 t 7.6) in body width. Body was elongate and broadest in region of hysterosoma. Body color was pale brown. Legs were robust except for the legs IV which were typical tarsonemid female legs terminating in a whiplike seta two times the length of the leg. Male of S. spir~kiw as 196.5 pm ( 176.5-222.8 + 15.8) in body length and 109.3 ym (98.6- 1 17.7 + 6.4) in body width. Anterior ends of apodemes 111 were extended further than apodemes IV. Femur IV had large inner median lateral flange. and inner anterior and outer median setae were short about equal length. Tarsal claw was stout and curved ventrally.

• Journal of Digital Convergence
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• v.14 no.8
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• pp.11-18
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• 2016

The purpose of this study is to compare the differences in human rights perception between people with disabilities and staffs in the disabled residential facilities. Using data from the '2014 Human Rights Survey on Disability in the Disabled Residential Facilities' for 602 facilities, the study compared their perception of human rights(16 items), including human rights guarantee(12 items) and human rights violation(4 items). Result showed that the rate of perception for human rights guarantee and violation(except staff violation) of staffs was higher than people with disabilities(p<.05). This study demonstrated that there were significant differences in human right perception between people with disabilities and staffs. The cause of this difference would be the conflict between roles of staff and needs of person with disabilities, absence of human rights indicators by mutual consent between the two. Our findings suggested a need for study on strategies to solve gap of perception between the two, such as integrated human rights education, developing consensual human rights indicators.

• Journal of the Korean Society for Railway
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• v.12 no.4
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• pp.582-589
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• 2009

The energy generated by braking vehicle would simply be converted into waste heat by its braking resistors if no other vehicle is accelerating at exactly the same time. Up to 45% of the tractive power of vehicles capable of returning energy to the power supply can be regenerated during braking and that this energy can be used to feed vehicles which are accelerating at the same time. Such synchronized braking and accelerating can not be coordinated, the ESS(energy storage system, here after) stores the energy generated during braking and discharges it again when a vehicle accelerates. The ESS is able to store and discharge energy extremely quickly, consequently enabling a complete exchange of energy between vehicles, even if they are not braking and accelerating at precisely the same time, as is most frequently the case in everyday service. The energy saving rate is related to the headway. If the headway is long/short, the energy saving goes up/down, When the headway is short, the ESS can not save much regenerative energy. The headway of SeoulMetro line 2 as the worst case is very short in Korea urban transit system. So, the energy saving rate will be very low. If the ESSs are applied to another railway system, we can expect that the effectiveness is better than the results of SeoulMetro line 2. This paper presents effects of energy saving obtained by applying the ESS to SeoulMetro line 2.

• Journal of the Korean Magnetics Society
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• v.22 no.3
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• pp.109-115
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• 2012

NeFeB anisotropy bonded magnet has proposed a new paradigm of weight reduction of small motors by replacing the conventional ferrite permanent magnets with its high magnetic property of 25 MGOe during last five years. It has also advanced by leaps and bounds in the field of motor industry for automobiles and electric power tools. And it has led a new innovation of fifty percent weight lightening compared to its current motors by correctly focusing on fuel performance improvement through weight lightening that automobile industry chased. There was, however, another price skyrocketing in 2011 after China had announced its export regulation in rare earth materials in July, 2010. And this price change has an extensive impact on the industries that consume rare earth magnets. This environmental change has caused technical challenge to improve the performance by using least amount of rare earth elements in NdFeB anisotropy bonded magnets, and led to make a new technical approach to a new applied field. In this article, we will show how each nation deals with this industrial issue, and introduce development trend and application of anisotropic NdFeB bonded magnets, so-called MAGFINE made by Aichi Steel Corp.

• Journal of Life Science
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• v.23 no.3
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• pp.377-382
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• 2013

In this study, we evaluated the antioxidant effects of Cordyceps, Ganoderma lucidum (Curtis) P. Karst and Phellinus linteus complexes. Three mushrooms were extracted using 70% ethanol, respectively, in ratios of 80:10:10(?). The electron-donating ability was measured using the DPPH radical mushroom complexes and showed effects of 66% in 500 ${\mu}g/ml$. ABTS radical cation decolorization measured 73% in 50 ${\mu}g/ml$ and had an effect similar to BHA in 500 ${\mu}g/ml$. In their superoxide anion radical scavenging ability, the mushroom complexes showed an effect of 41% in 10 ${\mu}g/ml$. The effect on the control of BHA was more than three times as high as BHA in 50 ${\mu}g/ml$ and 100 ${\mu}g/ml$ concentration. The results showed that lipid oxidation is an excellent inhibitor of lipid oxidation $Cu^{2+}$, compared to the $Fe^{2+}$ group. The results of superoxide dismutase (SOD) activity in the mushroom complexes showed a low effect of 13% in 500 ${\mu}g/ml$. Thus, the results of this study showed that the antioxidant effect of the mushroom complexes was excellent, indicating their potential as an antioxidant material.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.420-427
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• 1995

This study was conducted to investigate the preservative effect of low molecular weight chitosans on kimchi(2% salt concentration) during fermentation at $20^{\circ}C$. The pH and total acidity of control kimchi were lower and higher, respectively than those of kimchi samples containing chitosan. Reducing sugar content tended to be lower in control kimchi than in kimchi samples containing chitosan until 6 days of fermentation. Malic acid content was lower in control kimchi than in kimchi samples containing chitosan until 4 days of fermentation. Succinic acid content was higher in control kimchi than in kimchi samples containing chitosan at the 2 days of fermentation. Content of lactic and acetic acid also was higher in control kimchi than in kimchi samples containing chitosan at the 4 days of fermentation. The number of total microorganisms and those of microorganisms of Leuconostoc genus and Lactobacillus plantarum were higher in control kimchi than in kimchi samples containing chitosan. The number of microorganisms of Leuconostoc genus was lower in kimchi samples containing chitosan with the lower molecular weight chitosan than those with the higher molecular weight chitosan. Intensity of sensory sour taste and staled flavor were higher in control kimchi than in kimchi samples containing chitosan. There was not much difference in sensory firmness among kimchi samples, but control kimchi was evaluated slightly weaker than kimchi samples containing chitosan. Off-flavor was evaluated as weak in all the kimchi samples.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.348-354
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• 1994

Chitin and chitosan samples prepared from crab's shells under different conditions were compared for their physicochemical properties; and functionality in gastrointestinal tract by in vitro test. Their bulk density was in the range of $127{\sim}208\;mg/ml$, and their viscosity was $80{\sim}581\;cP$ in 0.1 chitin and $80{\sim}3,670\;cP$ in 0.5% chitosan solution, showing a wide variation. The degree of deacetylation in chitosan samples as determined by IR spectral analysis was relatively high, showing $81{\sim}93%$. At the same alkali concentration and reaction temperature, a longer reaction period gave an increased degree of deacetylation and lower viscosity. The water holding capacity of chitic substance became greater at higher soaking temperature; chitosan D at $37^{\circ}C$ showed the greatest value. Chitic substance with lower bulk density showed the higher water holding capacity. The retardation effect toward glucose absorption was higher in critic substances of lower density and higher water holding capacity; chitosan D showed the highest value of 38%. The retardation index toward bile acid absorption after 1 hour dialysis was $15{\sim}34%$ in chitic substances, 39% in pectin and 9% in cellulose. The retarding effect showed the highest value of 34% in chitosan D at 3% concentration.

• Journal of Gifted/Talented Education
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• v.26 no.1
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• pp.1-20
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• 2016

This study explored the cognitive characteristics and learning needs of economically disadvantaged gifted students. Gifted students(n=99), economically disadvantaged gifted students(n=43), and non-gifted students(n=50) participated in intelligence and creativity tests, and took self assessments of meta-cognition, epistemological beliefs, learning style preferences, and personal time usage. Superior abstract reasoning ability of economically disadvantaged gifted students was found because their scores on Raven's Test had risen rapidly compared to the other groups. Economically disadvantaged gifted students showed similar high scores as the gifted student on the Torrance Tests of Creativity Thinking-Figural, but not on Verbal. They were found to have a perception of the positive relationships among effort, learning abilities, and values of learning integrated knowledge with a general plan. However, they showed lower meta-cognitive control abilities than the gifted students in learning management and strategies, epistemological beliefs in value of rational operations, and time usage for learning. It is necessary to assign economically disadvantaged gifted students a task with various step by step methods of approach because these students prefer a new and creative task to difficult ones. Instruction plans such as developing language and meta-cognitive abilities and practical application of learning content was proposed.