• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5208-5213
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• 2011

In this paper, we proposed a new direction finding(DF) technology using TDOA(time-difference of arrival) and PDOA(phase difference of arriving signal) method. The proposed technology has a good DF accuracy without DF ambiguity. TDOA or PDOA technology is used to the most of intelligence systems in 21 century. The principle of TDOA is to receive a signal with two parallel antennas, measure the time difference of arrival signal, and converse the time difference to the direction of incident signal. Those technology make a DF system small size but the DF accuracy is low into short antenna installation distance. The principle of PDOA is similar to TDOA except measuring the phase difference of arrival signal, These technology get a good DF accuracy in short antenna installation distance but have a DF ambiguity. The proposed DF method is simulated into DF system operation environment with noise, and has a good DF accuracy.

• The Korean Journal of Mycology
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• v.11 no.1
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• pp.1-7
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• 1983

Nutritional characteristics and conditions for mycelial yield of Pleurotus ostreatus and Auricularia auricula-judae in shaking culture were investigated. Among the sugar substances, glucose and mannitol showed the good effect for mycelial yield of P. ostreatus, and mannitol and fructose were good for the mycelial yield of A. auricula-judae. Among the various organic acids, fumaric acid were good for the mycelial yield of P. ostreatus and A. auricula-judae. Among the nitrogen sources, peptone and urea showed the good result for mycelial yield of P. ostreatus, and peptone and casamino acid were good for mycelial yield of A. auricula-judae. Among the various amino acids, asparagin and threonine showed the good result for mycelial yield of P. ostreatus, and serine and threonine were good for mycelial yield of A. auricula-judae. Among the various vitamins, folic acid and thiamine were suitable for mycelial yield of P. ostreatus, and folic acid, inositol and riboflavin were suitable for mycelial yield of A. auricula-judae. Mycelial yield of P. ostreatus and A. auricula-judae were enhanced by the addition of $MgSO_4\;and\;KH_2PO_4$ at the concentration of 0.08 and 0.2% respectively. The optimum temperature and pH for mycelial yield were from $25\;to\;30^{\circ}C$ and pH 5.5 to 6.5 in P. ostreatus, and from $25\;to\;30^{\circ}C$ and pH 6.0 to 7.0 in A. auricula-judae.

• Journal of the Korean Ceramic Society
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• v.44 no.3 s.298
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• pp.157-161
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• 2007

Line width under $100\;{\mu}m$ with good resolution is difficult to achieve using conventional thick-film process utilizing screen printing method. However combined with lithography technology finer line and space for miniaturization and highly integrated package is achievable. In this study, photosensitive Ag paste of optimum formulation used for thick film lithography technology was fabricated by various Ag powder, glass powder and additives. As the result, line width of $30\;{\mu}m$ with good definition and reduced mismatch during co-firing with LTCC substrate was acquired. Formulated Ag paste was used to pattern embedded fine line inductor with over 90% yield.

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.234-237
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• 2008

• MALSORI
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• no.41
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• pp.61-71
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• 2001

How to teach intelligible, communicative pronunciation is a continuous question in the English education. Without good input, we can not expect good output. However, in EFL situation, it is very difficult to input the good English pronunciation, therefore, we have to find out the efficient and effective material for teaching pronunciation. One of the materials is song, because songs contain the linguistic and cultural traits of the language. The purpose of this paper is to clarify the reason why songs are good for teaching pronunciation. Koreans, who are syllable timed language users, have difficulties in English pronunciation of stress, rhythm, consonants cluster, linking or blending in connected speech. The 134 songs from wee sing are analyzed for how these traits show in songs. The result shows that we can acquire the traits easily and naturally through songs. And a lesson plan is offered as an example for teaching songs.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.891-893
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• 1992

Polymers have good electrical properties as an insulation material. Though they show more and less poor resistance to heat, radiation, and oxygen, the poor properties have been overcame by developing new resin with the saturated molecular structure and compounding resin with resistive fillers. Polymer insulators have many advantages; light weight, good mechanical properties, better contaimination performance, low cost by mass productivity, no destruction in many pieces, good flexibility in design, short manufacturing time. Usage of polymer insulators has increased rapidly with good credit on long term properties in advanced nations and will continue to grow.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.105-116
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• 2000

How to teach intelligible, communicative pronunciation is a continuous question in the English education. Without good input, we can not expect good output. However, in EFL situation, it is very difficult to input the good English pronunciation, therefore, we have to find out the efficient and effective material for teaching pronunciation. One of the materials is song, because songs contain the linguistic and cultural traits of the language. The purpose of this paper is to clarify the reason why songs are good for teaching pronunciation. Koreans, who are syllable timed language users, have difficulties in English pronunciation of stress, rhythm, consonants cluster, linking or blending in connected speech. The 134 songs from wee sing are analyzed for how these traits show in songs. The result shows that we can acquire the traits easily and naturally through songs. And a lesson plan is offered as an example for teaching songs.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.3
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• pp.816-824
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• 1996

The densification behaviors of copper powder under high temperature processing were investigated. Experimental data were obtained for copper powder under hot isostatic pressing, hot pressing and uniaxial compression. Finite element calculations from the constitutive models by McMeeking and co-workers were compared with the experimental data, The agreements between experimental data and theoretical calculations are reasonably good when hydrostatic stress is dominant, but not as good then deviatoric stress increases.

• ETRI Journal
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• v.25 no.6
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• pp.475-488
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• 2003

In this paper, we propose an efficient and simple fair queuing algorithm, called new starting potential fair queuing (NSPFQ), which has O(1) complexity for virtual time computation and also has good delay and fairness properties. NSPFQ introduces a simpler virtual time recalibration method as it follows a rate-proportional property. The NSPFQ algorithm recalibrates the system virtual time to the minimum virtual start time among all possible virtual start times for head-of-line packets in backlogged sessions. Through analysis and simulation, we show that the proposed algorithm has good delay and fairness properties. We also propose a hardware implementation framework for the scheduling algorithm.

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.435-439
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• 2019

An efficient one pot multicomponent synthesis of pyrimidinone derivatives of Biginelli type is described. 4-amino-6-aryl-pyrimidine-5-carbonitrile molecules were synthesized efficiently via three-component Biginelli-type condensation of aldehyde, malononitrile, and semicarbazone as urea substituent in the presence of a catalytic amount of PEG-400 as green medium under microwave irradiation. The reactions proceeded efficiently in the presence of microwave radiation to afford the desired products in good to excellent yields. Products have been confirmed by IR, and NMR spectral analysis. All the molecules were tested for their antimicrobial activity against E. coli, S. aureus, P. aeruginosa and C. tropicalis. Some of the compounds have shown moderate to good inhibition efficiency against both gram-positive and gram-negative bacteria. The potent activity was observed against the fungal species with minimum inhibition concentration 12.5 ㎍/mL.