• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.60-63
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• 1997

Dieletric ailed piezoelectric properties of Pb[$Zr_{0.45}$/ $Ti_{0.5-x}$/L $u_{x}$ (M $n_{1}$3//S $b_{2}$3)$_{0.05}$] $O_3$(0$\leq$x $\leq$0.03) were investigated. The partial substitution of $Ti^{4+}$ by a L $u^{3+}$ permitted improvement of the piezoelectric constant( $d_{33}$ ), electromechanical coupling factor ( $k_{p}$ ) and dielectric constant($\varepsilon$$_{33}$ /Sup T/). The dielectric loss(tan $\delta$ ) increased and mechanical quality factor(Qm) decreased with an increase of x were observed. A new piezoelectric material for actuator application was developed at x=0.02 with $d_{33}$ =370$\times$10$^{-2}$ /C/N, $k_{p}$ =58.5%, $\varepsilon$$_{33}$ $^{T}$ =1321, $Q_{m}$ =714 and tan $\delta$ =0.98%.%..%.%.

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.217.1-217.1
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• 2000

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.5
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• pp.167-182
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• 2002

Sprachverstehen ist ein interaktiver kognitiver Prozess. Der Verlauf des Sprachverstehens ist durch die kontinuierliche Interaktion von Bottom-up- und Top­down-Prozessen gekennzeichnet. Die eingehende Information wird durch die interaktive Nutzung verschiedener sprachlicher und aussersprachlicher Wissenssysteme verarbeitet. Herangewgen wird z. B. syntaktisches Wissen, lexikalisches und semantisches Wissen, Weltwissen und pragmatisches Wissen. Das hier vorgestellte Modell stellt den Begriff des lexikalischen Kopfes als $f\"{u}r$ die Verarbeitung von $S\"{a}tzen$ zentrales Konzept heraus. $Ambiguit\"{a}ten$ werden unter $Ber\"{u}cksichtigung$ der in ihnen $repr\"{a}sentierten\;Information\;aufzul\"{o}sen$ versucht Im Unterschied zu Prinzipien wie 'minimal attachment' rekurriert 'head attachment' nicht auf eine dem Satz zugrundeliegende Struktur, sondem allein auf lexikalische Information von $K\"{o}pfen$ und deren Reihenfolge an der $Oberfl\"{a}che$ eines Satzes. Head attachment ist daher $unabh\"{a}ngig$ von Annahmen $\"{u}ber$ syntaktische Strukturen. $W\"{a}hrend$ der 'tiefere Sinn' von Prinzipien wie 'minimal attachment' darin liegen soll, eine $m\"{o}glichst$ geringe Arbeitsspeicherbelastung durch Aufbau $m\"{o}glichst$ wenig komplexer Strukturen zu $gew\"{a}hrleisten$, erreicht 'head attachment' eine Entlastung durch die $Erm\"{o}glichung\;einer\;fr\"{u}hen$ semantischen Integration, da es Anbindungen in Abh\"{a}ngigkeit$ von dem Vorhandensein von $K\"{o}pfen\;vorschl\"{a}gt$. Es ist dieser Aspekt $\"{o}konomischer$ Verarbeitung, durch Verarbeitungs­heuristiken zu einer $m\"{o}glichst\;fr\"{u}hzeitigen$ Interpretation zu gelangen, der im hier vorgestellten Modell im Vordergrund steht, und zwar im Sinne einer semantikorientierten Syntaxverarbeitung.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.381-400
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• 1985

Twelve species of subfamily Leuciscinae from Korea are reviewed and keys to species and genera are provided. The species include Tribolodon hakonensis, T. branti, Phoxinus phoxinus, Moroco oxycephalus, M. steindachneri, M. keumgang, M. semotilus, Zacco platypus, Z. temminckii, Opsariichthys uncirostris amurensis, Aphyocypris chinensis and Squaliobarbus curriculus. In the present study M. lagowskii and O. bidens recorded previously in Korea have to be classified to M. steindachneri and O.u.amurensis based on several characters such as caudal peduncle depth, their distributions and lateral line scales, etc. A. chinensis from Korea is easily distinguished from that of mainland China in head length and caudal peduncle length. The skull and weberian apparatus of M. keumgang, endemir to Korea are described and compared with the other species of this subfamily. The diploid chromosome number of 9 species has three patterns: 2n=50 (T. hakonensis, P. phoxinus, M. oxycephalus, M. steindachneri and M. keumgang), 2n=48(Z. platypus, Z. temminckii and A. chinensis), 2n=76 (O. u. amurensis). Polyploidization or intraspecific polymorphism of chromosome was not observed in any species studied. Both species of P. phoxinus and A. chinensis are shown to be electrophoretically distinct from other taxa examined. The genera of subfamily Leuciscinae in Korea are represented by three possible groups: 1) Zacco-Opsariichthys-Tribolodon-Phoxinus-Morco, 2) Aphyocypris, and 3) Squaliobarbus.

• Honam Mathematical Journal
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• v.35 no.3
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• pp.445-506
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• 2013

Let ${\sigma}_s(N)$ denote the sum of the s-th power of the positive divisors of N and ${\sigma}_{s,r}(N;m)={\sum_{d{\mid}N\\d{\equiv}r\;mod\;m}}\;d^s$ with $N,m,r,s,d{\in}\mathbb{Z}$, $d,s$ > 0 and $r{\geq}0$. In a celebrated paper [33], Ramanuja proved $\sum_{k=1}^{N-1}{\sigma}_1(k){\sigma}_1(N-k)=\frac{5}{12}{\sigma}_3(N)+\frac{1}{12}{\sigma}_1(N)-\frac{6}{12}N{\sigma}_1(N)$ using elementary arguments. The coefficients' relation in this identity ($\frac{5}{12}+\frac{1}{12}-\frac{6}{12}=0$) motivated us to write this article. In this article, we found the convolution sums $\sum_{k<N/m}{\sigma}_{1,i}(dk;2){\sigma}_{1,j}(N-mk;2)$ for odd and even divisor functions with $i,j=0,1$, $m=1,2,4$, and $d{\mid}m$. If N is an odd positive integer, $i,j=0,1$, $m=1,2,4$, $s=0,1,2$, and $d{\mid}m{\mid}2^s$, then there exist $u,a,b,c{\in}\mathbb{Z}$ satisfying $\sum_{k& lt;2^sN/m}{\sigma}_{1,i}(dk;2){\sigma}_{1,j}(2^sN-mk;2)=\frac{1}{u}[a{\sigma}_3(N)+bN{\sigma}_1(N)+c{\sigma}_1(N)]$ with $a+b+c=0$ and ($u,a,b,c$) = 1(Theorem 1.1). We also give an elementary problem (O) and solve special cases of them in (O) (Corollary 3.27).

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.86-87
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• 2002

Fe과 Mo이 교대로 정렬해 있는 이중 페로브스카이트 구조를 갖는 $A_{2-x}$FeMo $O_{6}$(A=Ca, Sr, Ba) 화합물들은 망간 산화물들에 비해 높은 $T_{c}$ (310-420K)의 준강자성 상태를 갖는다.$^{1.3}$ 이 화합물들은 F $e^{3+}$ (S=5/2) 와 M $o^{5+}$(S=1/2) 스핀들 사이의 커다란 반강자성 상호작용으로 이론적으로 4$\mu$$_{B}$/f.u.의 $M_{s}$ 값을 갖는다. A-site의 평균 이온 반경( $r_{A}$)이 증가함에 따라 이 화합물들의 결정구조는 Monoclinic(A=Ca)에서 Tetragonal(Sr)과 Cubic(Ba)으로 점진적으로 변화한다.$^3$(중략)(중략)략)략)

• Environmental Analysis Health and Toxicology
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• v.13 no.1_2
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• pp.1-9
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• 1998

The ROS-producing potency of chromium compounds of several oxidation states were determined in the H4 cells. $K_2Cr_2O_7$ as Cr (VI), synthetic Cr (V) compounds and Cr (III) as TPP produced high level of ROS. However, ROS values of Cr-picolinate as Cr (III), CrCl$_2$, CrCI$_2$, were almost equal to the control. The effects of physiological antioxidants compounds which react with free radicals were examined for their effects on chromate-induced production of reactive oxygen species (ROS) in A549 cells after the addition of $K_2Cr_2O_7$. The compounds used were vitamin C (ascorbate), vitamin E ($\alpha$-tocopherol), superoxide dismutase (SOD) and catalase. The preincubation of ascorbate (200uM) with A549 cells for 20hr resulted in a significant reduction of hexavalent chromate(100uM) induced ROS. However, there is no effects of preincubation of the cells with vitamin E succinate (10 and 20uM, 20hr) on the ROS production. Also, the effects of Cr (VI) on the cell cycle of A549 cells was measured by adding the DNA intercalating agent, propidium iodide. S phase of the cell cycle was increased by the chromium (VI) compounds up to 20uM indicating toxicity or possible mitogenic action of the cell. The shoulder in Go/G1 phase at 20uM Cr (VI) with 24 hr treatment indicates apoptosis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.591-592
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• 2005

PTC Thermistors specimens were fabricated by added $MnO_2$ as donors, and $Nb_2O_5$ as acceptors and sintered $1250^{\circ}C$/2hrs. Average grain size decreased with increased in added $MnO_2$, and increased with added in $Nb_2O_5$. But, appeared liquid phase as $Bi_2O_3$ and $TiO_2$, affect to grain growth. XRD result, peak strength waslowed then crystallization not well, but, secondary phase were not showed all specimens. All specimens resistance were so high, about $40M\Omega$ over, couldn't measured to those resistance and doesn't appear PTCR effect.

• Microbiology and Biotechnology Letters
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• v.8 no.3
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• pp.181-191
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• 1980

For the purpose of studies on the citric acid production, some experiments were carried out with isolated strains. The results obtained were as follows. 1) The optimal culture media of the strain M-80 in surface culture contained 140g of sucrose, 3.0g of (N $H_4$)$_2$S $O_4$, 1.5g of K $H_2$P $O_4$, 0.2g of MgS $O_4$.7$H_2O$, 3.0mg of F $e^{++}$, 1.0mg of Z $n^{++}$, 0.5N HCI to a pH of 5.0 and distilled water to 1.0 liter; and that of the strain M-315 in surface culture contained 140g of sucrose, 2.0g of N $H_4$N $O_3$, 1.0g of K $H_2$P $O_4$, 0.25g of MgS $O_4$. 7$H_2O$, 2.0mg of F $e^{++}$, 2.0mg of Z $n^{++}$, 0.05mg of C $u^{++}$, 0.5N HCI to a pH of 4.5 and distilled water to 1.0 liter. While that of the strain M-315 in submerged culture contained 140g of sucrose, 2.5g of N $H_4$N $O_3$, 1.5g of K $H_2$P $O_4$, 0.3g of MgS $O_4$. 7$H_2O$, 3.0mg of F $e^{++}$, 0.1mg of C $u^{++}$, 0.5N HCI to a pH of 4.5 and distilled water to 1.0 liter. The optimal temperature and size of inoculum were mostly 28-3$0^{\circ}C$, 10$^{7}$ -10$^{8}$ spores/50ml, respectively. 2) Through the course of citric acid production, the growth of strains had nearly been completed, pH value was rapidly decreased below 2.0 and the content of sugar was also reduced, while the accumulation of citric acid in media was remarkably begun in about 3-4 days. The yields of citric acid generally reached the maximum level in 8-10 days in surface or submerged fermentation process. 3) Methanol was effective citric acid production when they were added to fermentation media. In the case of surface culture, by addition of 2％ (strain M-80), 3％ (strain M-315), the yields of citric acid was increased 6.5％, 20.6%, respectively and 5.0% yield was increased by addition of 3% methanol in submerged culture media of the strain M-315. 4) Chromatography analysis of culture broth after fermentation under optimal culture conditions detected that the majority of acid in media was citric acid. 72.1mg/ml, 98.1mg/ml, of citric acid were determined in surface culture media by strains of M-80, M-315, and 59.8 mg/ml of citric acid was contained in the submerged culture media by the strain M-315. strain M-315.

• Clean Technology
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• v.20 no.4
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• pp.390-397
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• 2014

This study was performed to investigate the effects of fluidizing media on $N_2O$ production in fluidized bed incineration of sewage sludge. The fluidized media were prepared in a form of 2 mm bead by mixing zeolite powders in our lab. Sand having 0.4 mm of the mean size showed 0.44 m/s of minimum fluidization velocity ($U_{mf}$), while the prepared zeolite media 0.5 m/s. When the ratio of fluidizing media height to the inside diameter of the incinerator (bed aspect ratio) increased from 1.4 to 3.1, it was found that $U_{mf}$ of the zeolite media was varied from 0.5 m/s to 0.7 m/s. Under the operation conditions in 1.79 of excess air ratio, $909^{\circ}C$ of bed temperature and ca. 1.65 m/s of superficial velocity, as the weight of fluidizing meadia was increased, $O_2$ concentration in the flue gas was slightly decreased, and $CO_2$ increased. Above 6 kg of fluidizing media weight (1.98 of bed aspect ratio), it was observed that $N_2O$ concentration was significantly reduced, which might result from the decomposition of $N_2O$ on the zeolite media rather than transformation of $N_2O$ to NOx. On the other hand, in a variation of the zeolite media mixing ratio to sand and bed temperature at a constant total bed height, significant difference was exhibited in $N_2O$ emission concentration according to the temperature. Considering the operation temperature in the incineration, the effective calcination temperature of the zeolite media was suggested to be around $900^{\circ}C$.