• Korean Journal of Materials Research
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• v.30 no.5
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• pp.239-245
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• 2020

Synthesizing one-dimensional nanostructures of oxide semiconductors is a promising approach to fabricate highefficiency photoelectrodes for hydrogen production from photoelectrochemical (PEC) water splitting. In this work, vertically aligned zinc oxide (ZnO) nanorod arrays are successfully synthesized on fluorine-doped-tin-oxide (FTO) coated glass substrate via seed-mediated hydrothermal synthesis method with the use of a ZnO nanoparticle seed layer, which is formed by thermally oxidizing a sputtered Zn metal thin film. The structural, optical and PEC properties of the ZnO nanorod arrays synthesized at varying levels of Zn sputtering power are examined to reveal that the optimum ZnO nanorod array can be obtained at a sputtering power of 20 W. The photocurrent density and the optimal photocurrent conversion efficiency obtained for the optimum ZnO nanorod array photoanode are 0.13 mA/㎠ and 0.49 %, respectively, at a potential of 0.85 V vs. RHE. These results provide a promising avenue to fabricating earth-abundant ZnO-based photoanodes for PEC water oxidation using facile hydrothermal synthesis.

• Korean Journal of Remote Sensing
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• v.24 no.5
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• pp.497-506
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• 2008

The needs for digital models of real environment such as 3D terrain or cyber city model are increasing. Most of applications related with modeling and simulation require virtual environment constructed from geospatial information of real world in order to guarantee reliability and accuracy of the simulation. The most fundamental data for building virtual environment, terrain elevation and orthogonal imagery is acquired from optical sensor of satellite or airplane. Providing interoperable and reusable digital model is important to promote practical application of high-resolution satellite imagery. This paper presents the new research regarding representation of geospatial information, especially for 3D shape and appearance of virtual terrain. and describe framework for constructing real-time 3D model of large terrain based on high-resolution satellite imagery. It provides infrastructure of 3D simulation with geographical context. Web architecture, XML language and open protocols to build a standard based 3D terrain are presented. Details of standard-based approach for providing infrastructure of real-time 3D simulation using high-resolution satellite imagery are also presented. This work would facilitate interchange and interoperability across diverse systems and be usable by governments, industry scientists and general public.

• Korean Journal of Remote Sensing
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• v.21 no.1
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• pp.31-49
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• 2005

We first review some history of the Global Geodynamics Project (GGP), particularly in the progress of ground-satellite gravity comparisons. The GGP Satellite Project has involved the measurement of ground-based superconducting gravimeters (SGs) in Europe for several years and we make quantitative comparisons with the latest satellite GRACE data and hydrological models. The primary goal is to recover information about seasonal hydrology cycles, and we find a good correlation at the microgal level between the data and modeling. One interesting feature of the data is low soil moisture resulting from the European heat wave in 2003. An issue with the ground-based stations is the possibility of mass variations in the soil above a station, and particularly for underground stations these have to be modeled precisely. Based on this work with a regional array, we estimate the effectiveness of future SG arrays to measure co-seismic deformation and silent-slip events. Finally we consider gravity surveys in volcanic areas, and predict the accuracy in modeling subsurface density variations over time periods from months to years.

• Journal of Surface Science and Engineering
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• v.52 no.5
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• pp.258-264
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• 2019

Assembling heterostructures by combining dissimilar oxide semiconductors is a promising approach to enhance charge separation and transfer in photoelectrochemical (PEC) water splitting. In this work, the CuO nanorods array/$Cu_2O$ thin film bilayered heterostructure was successfully fabricated by a facile method that involved a direct electrodeposition of the $Cu_2O$ thin film onto the vertically oriented CuO nanorods array to serve as the photoelectrode for the PEC water oxidation. The resulting copper-oxide-based heterostructure photoelectrode exhibited an enhanced PEC performance compared to common copper-oxide-based photoelectrodes, indicating good charge separation and transfer efficiency due to the band structure realignment at the interface. The photocurrent density and the optimal photocurrent conversion efficiency obtained on the CuO nanorods/$Cu_2O$ thin film heterostructure were $0.59mA/cm^2$ and 1.10% at 1.06 V vs. RHE, respectively. These results provide a promising route to fabricating earth-abundant copper-oxide-based photoelectrode for visible-light-driven hydrogen generation using a facile, low-cost, and scalable approach of combining electrodeposition and hydrothermal synthesis.

• Cross-Cultural Studies
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• v.26
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• pp.297-319
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• 2012

We all know how beautiful our wild and it's importance to our living planet Earth. But did you realise the speed at which man himself is damaging it's unique natural habitat. We are well on our way to destroy our forests, plants, wetlands. We are polluting our oceans and seas. This way, we're driving numerous animal species, plant species and many others into extinction. Everyone should be aware of the importance of our natural environment. We live in the period of echocide. Why we need nature to survive and how we can deal with the environmental problems we face. This paper has the purpose to reform city's environment. Because, Metropolis and megalopolis are the principal cause of environmental disruption. To reform the city is needed to consider digital technology in our age. In the face of economic and cultural globalization, many have argued that we live an increasingly placeless world. However, as a growing number of cities participate and compete in key marketplaces of advanced capitalism, the spectacle of the city is more than ever a significant medium of communication in its own right. In doing so, this work is focused specifically on the dimension of city's media environment. To that end, the paper examined U-City and U-Eco city. In this study, we will introduce the study on model of U-Eco City as one way for the eco-freindly future city.

• Cross-Cultural Studies
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• v.24
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• pp.5-18
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• 2011

This article offers a reflection on Frantz Fanon's diagnosis and analysis of French colonialism in Algeria. We will attempt to demonstrate that there is a concrete and clear connection between Fanon as the psychiatrist diagnosing the devastating effects of the French colonial system, and his subsequent political involvement in the Algerian revolution. This is not to say that each part does not contain valuable insights in their own rights, but rather to stress that without being read together, as a whole, one would miss a significant element in the understanding of the importance Fanon's thought subsequently came to play in the emancipation struggles of the colonized worldwide. Furthermore, we argue that it is crucial to understand the intimate connection between Fanon's psychiatric work, his diagnosis of colonial mental disorders, as well as diagnosis of the colonial system as such, and then his political engagement, in order to understand the particular context in which he favourably discusses the use of violence in the name of fighting against the oppressive system of colonialism. Above all, we argue that Fanon's critique of colonialism continues to spark controversy because it still represents the most powerful and incisive analysis of, as well as answer to, the troubled relationship between the blessed and the wretched of the earth.

• Korean Linguistics
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• v.80
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• pp.49-85
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• 2018

The purpose of this study is to research and systematize Jeju dialectal words about Jeju traditional housing culture and study them on the basis of lexical semantics. Vocabularies related to the names of the traditional thatched-roof house and its partial names, thatching, supplementary facilities, housing culture, etc. were categorized after recording in an ethnographic way from Seongeup folk village which is Important Folklore Material no.188, and studied them linguistically. Informants are fore people who were born and bred in Seongeup-ri and they are over 70. They have a lot of experiences building thatched-roof houses from a young age. There are 9 different categories - the kind of the house, partial names, exterior space, materials, tools, words about actions, doers, units, and folklore. Some new words related to Jeju traditional housing, which had not been in the list of Korean dictionary, could be introduced as a result of the study. For example, rice which are made when doing earth work is called Heukppap and adzes used to sharpen stones are called Dolchagui. The finding of These new words hopefully contribute to the promotion of Korean language as well as enrich vocabulary on housing. Furthermore, the collected vocabularies and oral materials could be used as important educational materials to comprehend Jeju traditional housing culture.

• Resources Recycling
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• v.28 no.2
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• pp.3-13
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• 2019

Aluminum is the most abundant metal and the second most plentiful metallic element in the earth's crust, after silicon. Aluminum is a light, conductive, and corrosion resistant metal with strong affinity for oxygen. However, the primary aluminum production process is highly energy intensive. The recycling of aluminum scrap reduces the energy consumption and environmental burden, comparing to the primary metal production. However, the amount of the recovered metal from scrap is limited because of the difficulties to remove the impurities in the scrap. This work provides an overview of the aluminum production and recycling process, from the preparation of alumina to the scrap upgrading and the melting process.

• Journal of Powder Materials
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• v.26 no.4
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• pp.334-339
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• 2019

To meet the current demand in the fields of permanent magnets for achieving a high energy density, it is imperative to prepare nano-to-microscale rare-earth-based magnets with well-defined microstructures, controlled homogeneity, and magnetic characteristics via a bottom-up approach. Here, on the basis of a microstructural study and qualitative magnetic measurements, optimized reduction conditions for the preparation of nanostructured Sm-Co magnets are proposed, and the elucidation of the reduction-diffusion behavior in the binary phase system is clearly manifested. In addition, we have investigated the microstructural, crystallographic, and magnetic properties of the Sm-Co magnets prepared under different reduction conditions, that is, $H_2$ gas, calcium, and calcium hydride. This work provides a potential approach to prepare high-quality Sm-Co-based nanofibers, and moreover, it can be extended to the experimental design of other magnetic alloys.

• Journal of Climate Change Research
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• v.5 no.4
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• pp.313-321
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• 2014

Agriculture is a vulnerable sector to climate change because it is a primary industry directly exposed to climate. At the same time, it is a sector emitting greenhouse gases during agricultural activities, thereby affecting climate change. However, agriculture is a nascent subject under the UNFCCC. The agriculture sector needs both adaptation and mitigation. Currently, co-benefit of adaptation and mitigation is emphasized during climate change negotiation. Developing country parties are in a position to focus on adaptation rather than mitigation. As a result, mitigation is not being addressed enough during climate negotiation. Agriculture has been addressed through Nairobi Work Programme and NAPA. Since current efforts for greenhouse gas reduction are not sufficient for stabilizing the atmospheric system of the Earth to prevent climate change, the agriculture sector should also be considered for greenhouse gas reduction. For this, MRV for small farmers in developing countries and incentives for their mitigation efforts should be developed in agriculture sector. In addition, it is necessary to strengthen international cooperation for developing capacities for vulnerable countries and people to climate change.