• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.799-802
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• 2003

[ $LaNiO_3$ ](LNO) thin films were deposited on various substrates as Si and $Al_2O_3$ by sol-gel process using lanthanum nitrate and nickel acetate. The structure and orientation of the films were characterized by X-ray diffraction. The orientation factors of films on Si(100), Si(111), $SiO_2/Si(100)$ and $Al_2O_3$were 97%, 63%, 73%, and 24% respective. The conductivity was $7.6{\times}10^{-3}{\Omega}{\cdot}cm$ with 10 times coating at Si(100) substrate.

• Journal of Navigation and Port Research
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• v.37 no.6
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• pp.611-616
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• 2013

This paper studies relationship between typhoon and El Ni$\tilde{n}$o La Ni$\tilde{n}$a events by using 25 years meteorological data of KMA and JMA. The results are listed below. Annual mean number of typhoon's occurrence in El Ni$\tilde{n}$o event year is 23.9, and that in La Ni$\tilde{n}$a event year is 24.9. The number of typhoon's occurrence decreases in El Ni$\tilde{n}$o event year. Mean central minimum pressure and mean maximum wind speed in El Ni$\tilde{n}$o event year are 959.3hPa and 35.8m/s, and those in La Ni$\tilde{n}$a event year are 965.5hPa and 33.7m/s respectively. Intension of typhoon is stronger in El Ni$\tilde{n}$o event year than La Ni$\tilde{n}$a event year. To be more specific mean central minimum pressure is lower 6.2hPa and mean maximum wind speed is stronger 2.1m/s. This result is closely connected with sea area of typhoon's occurrence. Typhoons in El Ni$\tilde{n}$o event year are more likely to occur in east of 150E and south of 10N, but those in La Ni$\tilde{n}$a event year are more likely to occur in 120-150E and north of 20N. Typhoons which occur in east of 150E and south of 10N can be stronger because the typhoons move in broad sea area of high sea surface temperature in western North Pacific.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.6
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• pp.543-549
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• 2013

In this study, $La_{0.9}Sr_{0.1}Cr_{0.7}M_{0.3}O_{3{\pm}{\delta}}$ (M=Mn, Ru, Fe, Ni) were prepared by sol-gel method and water gas shift reaction with simulated coal-derived syngas between $400{\sim}650^{\circ}C$ was conducted to evaluate the catalytic activity of prepared catalysts. Physico-chemical properties were characterized by XRD, BET, SEM-EDS and TPR. The formation of perovskite crystallite, $LaCrO_3$ was confirmed and the highest surface area was measured with $La_{0.9}Sr_{0.1}Cr_{0.7}Mn_{0.3}O_{3{\pm}{\delta}}$. Equilibrium conversion of CO above $550^{\circ}C$ was achieved except $La_{0.9}Sr_{0.1}Cr_{0.7}Fe_{0.3}O_{3{\pm}{\delta}}$. and methanation reaction was carried out as side reaction of water gas shift reaction with $La_{0.9}Sr_{0.1}Cr_{0.7}Ni_{0.3}O_{3{\pm}{\delta}}$ and $La_{0.9}Sr_{0.1}Cr_{0.7}Ru_{0.3}O_{3{\pm}{\delta}}$. Conclusively, $La_{0.9}Sr_{0.1}Cr_{0.7}M_n{0.3}O_{3{\pm}{\delta}}$ was the most suitable catalyst of water gas shift reaction above $500^{\circ}C$ for CO conversion and hydrogen production.

• Korean Journal of Materials Research
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• v.7 no.10
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• pp.871-871
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• 1997

(1-x)CaTiO/sub 3/-xLa(Zn/sub 1/2/Ti/sub 1/2/)O/sub 3/의 마이크로 유전특성을 조사하였다. x가 증가함에 따라 비유전율과 공진주파수의 온도계수는 감소하였으며, Qㆍf/sub 0/는 증가하였다. 그 결과 x=0.5인 (Ca/sub 0.5/La/sub 0.5/)(Ti/sub 0.75/Zn/sub 0.25/)O/sub 3/의 조성에서 ε/sub r/=51, Qㆍf/sub 0/=38,000 (at 7 GHz), τ/sub f/=+5ppm/℃의 유전특성이 나타났다. (Ca/sub 0.5/La/sub 0.5/)(Ti/sub 0.75/Zn/sub 0.25/) O/sub 3/조성의 소결온도를 저하시키기 위하여 Bi/sub 2/O/sub 3/를 주조성으로한 소결체를 첨가하여 소결 및 유전특성을 조사하였다. 1wt% 0.76Bi/sub 2/O/sub 3/-0.24NiO가 첨가된 경우 소결온도는 150℃ 낮아졌으며, 비유전율 (ε/sub r/), 공진주파수의 온도계수(τ/sub f), Qㆍf/sub 0/가 각각 50+5ppm/℃, 35,000인 마이크로파 유전특성이 얻어졌다. 또한 3wt%의 0.76Bi/sub 2/O/sub 3/-0.24NiO가 첨가된 경우 소결온도는 200℃ 저하되었고, 비유전율 (ε/sub r/)과 공진주파수의 온도계수 (τ/sub f)는 변하기 않았으나, Qㆍf/sub 0/값이 38,000에서 25,000으로 저하되었다.

• Journal of the Korean Ceramic Society
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• v.34 no.6
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• pp.629-635
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• 1997

The effects of the annealing atmospheres(O2, N2) and sintering additives that Bi2O3 is a major composition on the microwave dielectric and sintering propertie of (1-x)CaTiO3-xLaAlO3 system were investigated. The annealing atmospheres and the increase of annealing time after sintering did not affect the relative dielectric constant($\varepsilon$r) and temperature coefficient of resonant frequency($\tau$f) of (1-x)CaTiO3-xLaAlO3 system. However, the Q.f0 values of (1-x)CaTiO3-xLaAlO3 were very sensitive to annealing atmospheres. As the annealing time increased under O2 atmosphere the Q.f0 values of (1-x)CaTiO3-xLaAlO3 enhanced untill 10 hrs in 0.3$\leq$x$\leq$0.6 region, but degraded over that time. The increasing rate of Q.f0 value increased wth increasing x. On the other hand, as the annealing time increased under N2 atmosphere the Q.f0 values were constant in x$\leq$0.6 region, increased gradually in x$\geq$0.7 region. When 0.97Bi2O3-0.03Al2O3 and 0.76Bi2O3-0.24NiO of 3wt% as sintering additives were added to (Ca0.5La0.5) (Ti0.5Al0.5)O3 (x=0.5) the sintering temperature of 1$600^{\circ}C$ was lowered to 140$0^{\circ}C$, and the relative dielectric constant($\varepsilon$r) and temperature coefficient of resonant frequency($\tau$f) were not nearly changed. The addition of 0.97Bi2O3-0.03Al2O3 and 0.76Bi2O3-0.24NiO of 3wt% to (Ca0.5La0.5)(Ti0.5Al0.5)O3 made the Q.f0 values to be lower about 15% and 34%, respectively.

• Atmosphere
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• v.24 no.3
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• pp.283-301
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• 2014

In 2010, only 14 tropical cyclones (TCs) were generated over the western North Pacific (WNP), which was the smallest since 1951. This study summarizes characteristics of TCs generated in 2010 over the WNP and investigates the causes of the record-breaking TC genesis. A long-term variation of TC activity in the WNP and verification of official track forecast in 2010 are also examined. Monthly tropical sea surface temperature (SST) anomaly data reveal that El Ni$\tilde{n}$o/Southern Oscillation (ENSO) event in 2010 was shifted from El Ni$\tilde{n}$o to La Ni$\tilde{n}$a in June and the La Ni$\tilde{n}$a event was strong and continued to the end of the year. We found that these tropical environments leaded to unfavorable conditions for TC formation at main TC development area prior to May and at tropics east of $140^{\circ}E$ during summer mostly due to low SST, weak convection, and strong vertical wind shear in those areas. The similar ENSO event (in shifting time and La Ni$\tilde{n}$a intensity) also occurred in 1998, which was the second smallest TC genesis year (16 TCs) since 1951. The common point of the two years suggests that the ENSO episode shifting from El Ni$\tilde{n}$o to strong La Ni$\tilde{n}$a in summer leads to extremely low TC genesis during La Ni$\tilde{n}$a although more samples are needed for confidence. In 2010, three TCs, DIANMU (1004), KOMPASU (1007) and MALOU (1009), influenced the Korean Peninsula (KP) in spite of low total TC genesis. These TCs were all generated at high latitude above $20^{\circ}N$ and arrived over the KP in short time. Among them, KOMPASU (1007) brought the most serious damage to the KP due to strong wind. For 14 TCs in 2010, mean official track forecast error of the Korea Meteorological Administration (KMA) for 48 hours was 215 km, which was the highest among other foreign agencies although the errors are generally decreasing for last 10 years, suggesting that more efforts are needed to improve the forecast skill.

• Economic and Environmental Geology
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• v.30 no.1
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• pp.1-14
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• 1997

The shales from the Euiseong area are interbedded along the bedding in Cretaceous Gyeongsang Supergroup, which are composed mainly of quartz, plagioclase, K-feldspar and associated with trace amount of biotite, muscovite, chlorite, pyrite, hematite, carbonate and clay minerals. The ratio of $Al_2O_3/Na_2O$ and $K_2O/Na_2O$ in shales from the Shindong Group are ranged from 9.16 to 24.32 and from 1.70 to 5.97, and the Hayang Group ranged from 2.76 to 8.89 and from 0.42 to 2.74, which are negative correlated between $K_2O/Na_2O$ and $Al_2O_3/Na_2O$ against $SiO_2/Al_2O_3$ respectively. Those are suggested that controlled of mineral compositions in shales due to substitution and migration of elements by sedimentation and diagenesis. These shale formation were deposited in basin of terrestrial environments originated from the igneous rocks, and the REE of these rocks are not influenced with diagenesis and hydrothermal alterations on the basis of $Al_2O_3$ versus La, La against Ce, Zr versus Yb, the ratios of La/Ce (0.43 to 0.62) and Th/U (1.11 to 10.71). The narrow range in trace and REE element characteristics as Co/Th (0.63 to 1.92), La/Sc (1.98 to 5.90), Sc/Th (0.58 to 1.30), V/Ni (0.90 to 3.25), Cr/V (0.45 to 1.78), Ni/Co (1.88 to 6.67) and Zr/Hf (30.04~60.87) of these shales argues for inefficient mixing of the simple source lithologies during sedimentation. These rocks also show much variation in $La_N/Yb_N$ (6.90 to 17.02), Th/Yb (4.17 to 13.68) and La/Th (1.98 to 5.90), and their origin is explained by derivation from a mixture of intermediate to acidic igneous rocks.

• Journal of the Korean earth science society
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• v.24 no.1
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• pp.22-29
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• 2003

Temporal and spatial variability of precipitation (P), evaporation (E), and moisture balance (P-E; precipitation minus evaporation) has been investigated over the tropical ocean during the period from January 1998 to July 2001. Our data were analyzed by the EOF method using the satellite P and E observations made by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) and the Special Sensor Microwave/Imager (SSM/I). This analysis has been performed for two three-year periods as follow; The first period which includes the El Ni${\tilde{n}}$o in early 1998 ranges from January 1998 to December 2000, and the second period which includes the La Ni${\tilde{n}}$o events in the early 1999 and 2000 (without El Ni${\tilde{n}}$o) ranges from August 1998 to July 2001. The areas of maxima and high variability in the precipitation and in the P-E were displaced from the tropical western Pacific and the ITCZ during the La Ni${\tilde{n}}$o to the tropical middle Pacific during the El Ni${\tilde{n}}$o, consistent with those in previous P studies. Their variations near the Korean Peninsula seem to exhibit a weakly positive correlation with that in the tropical Pacific during the El Ni${\tilde{n}}$o. The evaporation, out of phase with the precipitation, was reduced in the tropical western Pacific due to humid condition in boreal summer, but intensified in the Kuroshio and Gulf currents due to windy condition in winter. The P-E variability was determined mainly by the precipitation of which the variability was more localized but higher by 2-3 times than that of evaporation. Except for the ITCZ (0-10$^{\circ}$N), evaporation was found to dominate precipitation by ${\sim}$2 mm/day over the tropical Pacific. Annual and seasonal variations of P, E, and P-E were discussed.

• Korean Journal of Materials Research
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• v.7 no.10
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• pp.872-876
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• 1997

(1-x)CaTi $O_{3}$-xLa(Z $n_{1}$2/ $Ti_{1}$2/) $O_{3}$의 마이크로 유전특성을 조사하였다. x가 증가함에 따라 비유전율과 공진주파수의 온도계수는 감소하였으며, Qㆍ $f_{0}$는 증가하였다. 그 결과 x=0.5인 (C $a_{0.5}$L $a_{0.5}$)( $Ti_{0.75}$Z $n_{0.25}$) $O_{3}$의 조성에서 $\varepsilon$$_{r}$=51, Qㆍ $f_{0}$=38,000 (at 7 GHz), $\tau$$_{f}$=+5ppm/$^{\circ}C$의 유전특성이 나타났다. (C $a_{0.5}$L $a_{0.5}$)( $Ti_{0.75}$Z $n_{0.25}$) $O_{3}$조성의 소결온도를 저하시키기 위하여 B $i_{2}$ $O_{3}$를 주조성으로한 소결체를 첨가하여 소결 및 유전특성을 조사하였다. 1wt% 0.76B $i_{2}$ $O_{3}$-0.24NiO가 첨가된 경우 소결온도는 15$0^{\circ}C$ 낮아졌으며, 비유전율 ($\varepsilon$$_{r}$), 공진주파수의 온도계수($\tau$$_{f}$), Qㆍ $f_{0}$가 각각 50+5ppm/$^{\circ}C$, 35,000인 마이크로파 유전특성이 얻어졌다. 또한 3wt%의 0.76B $i_{2}$ $O_{3}$-0.24NiO가 첨가된 경우 소결온도는 20$0^{\circ}C$ 저하되었고, 비유전율 ($\varepsilon$$_{r}$)과 공진주파수의 온도계수 ($\tau$$_{f}$)는 변하기 않았으나, Qㆍ $f_{0}$값이 38,000에서 25,000으로 저하되었다. 25,000으로 저하되었다.되었다.되었다.되었다.

• Economic and Environmental Geology
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• v.30 no.5
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• pp.417-431
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• 1997

Characteristics of sedimentary rocks and enrichment of toxic elements in shale and coal from the Chungnam coal field were investigated based upon geochemistry of major, trace and rare earth elements. Shale and coal of the area are interbedded along the Traissic to the Jurassic Daedong Supergroup, which can be subdivided into grey shale, black shale and coal. The coal had been mined, however all the mines are abandonded due to the economic problems. The shale and coal are characterized by relatively low contents of $SiO_2$, and $Al_2O_3$ and high levels of loss-on-ignition (LOI), CaO and $Na_2O$ in comparison with the North American Shale Composite (NASC). Light rare earth elements (La, Ce, Yb and Lu) are highly enriched with the coal. Ratios of $Al_2O_3/Na_2O$ and $K_2O/Na_2O$ in shale and coal range from 30.0 to 351.8 and from 4.2 to 106.8, which have partly negative correlations against $SiO_2/Al_2O_3$ (1.24 to 6.06), respectively. Those are suggested that controls of mineral compositions in shale and coal can be due to substitution and migration of those elements by diagenesis and metamorphism. Shale and coal of the area may be deposited in terrestrial basin deduced from high C/S (39 to 895) and variable composition of organic carbon (0.39 to 18.40 wt.%) and low contents of reduced sulfur (0.01 to 0.05 wt.%). These shale and coal were originated from the high grade metamorphic and/or igneous rocks, and the rare earth elements of those rocks are slightly influenced with diagenesis and metamorphism on the basis of $Al_2O_3$ versus La, La against Ce, Zr versus Yb, the ratios of La/Ce (0.38 to 0.85) and Th/U (3.6 to 14.6). Characteristics of trace and rare earth elements as Co/Th (0.07 to 0.86), La/Sc (0.31 to 11.05), Se/Th (0.28 to 1.06), V/Ni (1.14 to 3.97), Cr/V (1.4 to 28.3), Ni/Co (2.12 to 8.00) and Zr/Hf (22.6~45.1) in the shale and coal argue for inefficient mixing of the simple source lithologies during sedimentation. These rocks also show much variation in $La_N/Yb_N$ (1.36 to 21.68), Th/Yb (3.5 to 20.0) and La/Th (0.31 to 7.89), and their origin is explained by derivation from a mixture of mainly acidic igneous and metamorphic rocks. Average concentrations in the shale and coal are As=7.2 and 7.5, Ba=913 and 974, Cr=500 and 145, Cu=20 and 26, Ni=38 and 35, Pb=30 and 36, and Zn=77 and 92 ppm, respectively, which are similar to those in the NASC. Average enrichment indices for major elements in the shale (0.79) and coal (0.77) are lower than those in the NASC. In addition, average enrichment index for rare earth elements in coal (2.39) is enriched rather than the shale (1.55). On the basis of the NASC, concentrations of minor and/or environmental toxic elements in the shale and coal were depleted of all the elements examined, excepting Cr, Pb, Rb and Th. Average enrichment indices of trace and/or potentially toxic elements (As, Cr, Cu, Ni, Pb, U and Zn) are 1.23 to 1.24 for shale and 1.06 to 1.22 for coal, respectively.