• Journal of Korean Society for Geospatial Information Science
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• v.20 no.1
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• pp.53-63
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• 2012

As a result of the economical loss caused by unusual climate changes resulting from emission of excessive green house gases such as carbon dioxide which is expected to account for 5~20% of the world GDP by 2100, researching technologies regarding the reduction of carbon dioxide emission is being favored worldwide as a part of the high value-added industry. As one of the Annex II countries of Kyoto Protocol of 1997 that should keep the average $CO_2$ emission rate of 5% by 2013, South Korea is also dedicated to the researches and industries of $CO_2$ emission reduction. In this study, Application of LiDAR data & KOMPSAT-2 satellite image for calculated forest Biomass. Raw LiDAR data's tree numbers and tree-high with field survey data resulted in 90% similarity of objects and an average of 0.3m difference in tree-high. Calculating the forest biomass through forest type information categorized as KOMPSAT-2 image and LiDAR data's tree-high data of tree enabled the estimation of $CO_2$ absorption and forest biomass of forest type, The similarity between the field survey average of 90% or higher were analyzed.

• Journal of Digital Convergence
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• v.19 no.12
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• pp.377-382
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• 2021

In order to advance forest resource management, it is necessary to solve problems such as the aging of forest-related industry workers and the field investigation system centered on manpower. Therefore, in this study, the trend of establishment and utilization of overseas forest geospatial information applied with the latest technology for scientific forest resource management was investigated to identify the domestic application plan. Overseas, photogrammetry and LiDAR technologies were being used to construct and utilize forest geospatial information. In the case of photogrammetry, it was used to measure the volume of vegetation, diameter, and tree height. And LiDAR technology has been applied to the measurement of diameter, and tree height. Through the analysis of overseas cases, it was identified how to construct forest geospatial information using photogrammetry and LiDAR, and it was found that LiDAR showed higher accuracy than photogrammetry. In the future, if the construction of forest geospatial information using various LiDAR sensors are performed and the accuracy and work efficiency are analyzed, it will be possible to present the possibility of using new technologies in the construction of forest geospatial information in Korea.

• Korean Journal of Materials Research
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• v.20 no.2
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• pp.72-77
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• 2010

Glass-ceramics were fabricated by heat-treatment of glass obtained by melting a coal bottom ash with $Li_2O$ addition. The main crystal grown in the glass-ceramics, containing 10 wt% $Li_2O$, was $\beta$-spodumene solid solution, while in $Li_2O$ 20 wt% specimen was mullite, identified using XRD. The activation energy and Avrami constant for crystallization were calculated and showed that bulk crystallization behavior will be predominant, and this expectation agreed with the microstructural observations. The crystal phase grown in $Li_2O$ 10 wt% glass-ceramics had a dendrite-like shaped whereas the shape was flake-like in the 20 wt% case. The thermal expansion coefficient of the $Li_2O$ 10 wt% glass-ceramics was lower than that of the glass having the same composition, owing to the formation of a $\beta$-spodumene phase. For example, the thermal expansion coefficient of $Li_2O$ 10 wt% glass-ceramics was $20\times10^{-7}$, which is enough for application in various heat-resistance fields. But above 20 wt% $Li_2O$, the thermal coefficient expansion of glass-ceramics, on the contrary, was higher than that of the same composition glass, due to formation of mullite.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.10
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• pp.1545-1550
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• 2022

In this research, a method for minimizing the replacement time of AMR (Autonomous Mobile Robot), which is used in various industrial groups such as logistics and manufacturing, was studied in the event of a LiDAR failure. In this regard, a general LiDAR exchange process was defined and a new exchange process based on the newly designed jig, which is mounted on the AMR, for the quick change of LiDAR was proposed. The experiment is conducted using commercialized AMR which was developed for application in the factory of an automobile manufacturing company. It was confirmed that LiDAR can be replaced and aligned within 24 minutes when the new exchange process is employed, which is about 76% or more shorter than the general LiDAR exchange process. As a result, we can minimize AMR downtime and overall process delays by applying the proposed process.

• Journal of Electrochemical Science and Technology
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• v.14 no.3
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• pp.293-300
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• 2023

The global energy storage markets have gravitated to high-energy-density and low cost of lithium-ion batteries (LIBs) as the predominant system for energy storage such as electric vehicles (EVs). High-Ni layered oxides are considered promising next-generation cathode materials for LIBs owing to their significant advantages in terms of high energy density. However, the practical application of high-Ni cathodes remains challenging, because of their structural and surface instability. Although extensive studies have been conducted to mitigate these inherent instabilities, a two-step process involving the synthesis of the cathode and a dry/wet coating is essential. This study evaluates a one-step β-Li₂SnO₃ layer coating on the surface of LiNi_0.8Co_0.2O₂ (NC82) via the thermal segregation of Sn owing to the solubility limit with respect to the synthesis temperature. The doping, segregation, and phase transition of Sn were systematically revealed by structural analyses. Moreover, surface-engineered 5 mol% Sn-coated LiNi_0.8Co_0.2O₂ (NC82_Sn5%) exhibited superior capacity retention compared to bare NC82 owing to the stable surface coating layer. Thus, the developed one-step coating method is suitable for improving the properties of high-Ni layered oxide cathode materials for application in LIBs.

• Journal of Sensor Science and Technology
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• v.11 no.6
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• pp.371-377
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• 2002

$Y_2O_3:Eu^{3+}$ and Li-doped $Y_2O_3:Eu^{3+}$ thin films have been grown on sapphire substrates using a pulsed laser deposition technique. The thin film phosphors were deposited at a substrate temperature of $600^{\circ}C$ under the oxygen pressure of 100, 200 and 300 mTorr. The films grown under different deposition conditions have been characterized using microstructural and luminescent measurements. The crystallinity and photoluminescence (PL) of the films are highly dependent on the oxygen pressure. The PL brightness data obtained from $Y_2O_3:Eu^{3+}$ films grown under optimized conditions have indicated that sapphire is one of the most promising substrate for the growth of high quality $Y_2O_3:Eu^{3+}$ thin film red phosphor. In particular, the incorporation of $Li^{+}$ ions into $Y_2O_3$ lattice could induce a remarkable increase of PL. The highest emission intensity was observed with LiF-doped $Y_{1.84}Li_{0.08}Eu_{0.08}O_3(Y_2O_3LiEu)$, whose brightness was increased by a factor of 2.7 in comparison with that of $Y_2O_3:Eu^{3+}$ films. This phosphor may promise for application to the flat panel displays.

• Journal of Electrochemical Science and Technology
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• v.12 no.4
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• pp.424-430
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• 2021

The element iron (Fe) is affordable and abundantly available, and thus, it finds use in a wide range of applications. As regards its application in rechargeable lithium-ion batteries (LIBs), the electrochemical reactions of Fe must be clearly understood during battery charging and discharging with the LIB electrolyte. In this study, we conducted systematic electrochemical analyses under various voltage conditions to determine the voltage at which Fe corrosion begins in general lithium salts and organic solvents used in LIBs. During cyclic voltammetry (CV) experiments, we observed a large corrosion current above 4.0 V (vs. Li/Li⁺). When a constant voltage of 3.7 V (vs. Li/Li⁺), was applied, the current did not increase significantly at the beginning, similar to the CV scenario; on the other hand, at a voltage of 3.8 V (vs. Li/Li⁺), the current increased rapidly. The impact of this difference was visually confirmed via scanning electron microscopy and optical microscopy. Our X-ray photoelectron spectroscopy measurements showed that at 3.7 V, a thick organic solid electrolyte interphase (SEI) was formed atop a thin fluoride SEI, which means that at ≥3.8 V, the SEI cannot prevent Fe corrosion. This result confirms that Fe corrosion begins at 3.7 V, beyond which Fe is easily corrodible.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.157-160
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• 2010

Terrestrial LiDAR data contains outliers which do not need in processing purpose. That is inefficient in the aspect of productivity. These noise requires manual process to be removed, which causes inefficiency in aspect of productivity. The purpose of this research is to demonstrate a possibility of automatic outlier removal of LiDAR data using 3D Tensor Voting method. For this, we presented in this article about the procedure to perform the application of Tensor Voting algorithm to the real data from terrestrial LiDAR.

• Journal of Surface Science and Engineering
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• v.28 no.1
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• pp.46-54
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• 1995

An electrochromic(EC) cell was constructed using $WO_3$ as a electrochromic material and NiO as a counter electrode, deposited onto ITO-coated glass by the implementation of electron beam evaporation. The electrolytic media were both lithium and proton conducting polymers such as poly-acrylonitrile(PAN)-$LiClO_4$, poly-ethylene oxide(PEO)-$LiClO_4$, poly-vinyl butyral(PVB)-LiCl and PVB-H$_3$$PO_4$. Potentiodynamic cycling of the cells using PAN-$LiClO_4$, or PVB-$H_3$$PO_4$ electrolyte yielded a transmission variation of more than 40% at the wavelength of 632.8 nm within less than 10 sec response time at room temperature. These results indicate that these electrolytes, transparent in gel type, are premising for the application in large area electrochromic windows.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.11
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• pp.905-910
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• 2011

To study encapsulation method for large-area organic light emitting diodes (OLEDs), red emitting OLEDs were fabricated, on which LiF and Al were deposited as inorganic protective films. And then the OLED was attached to flat glass by printing method using epoxy. In case of direct coating of epoxy onto OLED by printing method, luminance and current efficiency were remarkably decreased because of the damage to the OLED by epoxy. In case of depositing LiF and Al as inorganic protective films and then coating of epoxy onto OLED, luminance and current efficiency were not changed. OLED lifetime was more increased through inorganic protective films between OLED and flat glass than that without any encapsulation (8.8 h), i.e., 47 (LiF/Al/epoxy/glass), 62 (LiF/Al/LiF/epoxy/glass), and 84 h (LiF/Al/Al/epoxy/glass). The characteristics of OLED encapsulated with inorganic protective films (attached to flat glass) showed the possibility of application of protective films.