• Journal of the Korean Electrochemical Society
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• v.13 no.4
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• pp.256-263
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• 2010

A Crofer 22 APU mesh coated with a conductive ceramic material was developed as an alternative cathode current collector to Ag-based materials for solid oxide fuel cells. $(La_{0.80}Sr_{0.20})_{0.98}MnO_3$ (LSM) layer was deposited onto the Crofer mesh using a spray-coating technique, in an attempt to mitigate the degradation of electrical properties due to surface oxidation at high temperatures. The oxidation experiments at $800^{\circ}C$ in air indicated that the areaspecific resistance (ASR) of the LSM-coated Crofer mesh was strongly dependent on the wire diameter and the contact morphology between mesh and cell. In addition, the post-heat-treatment in $H_2/N_2$ resulted in a reduced thickness of Cr-containing oxide scales at the interface between Crofer mesh and LSM layer, leading to a decreased ASR.

• Korean Journal of Plant Taxonomy
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• v.37 no.2
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• pp.203-215
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• 2007

Uchiyama, Tomijiro visited the Korean peninsula including Busan, Incheon, Nampo, Pyongyang, Seoul, Mt. Geumgang of Gangwon-do, and Jeju-do twice for his plant collections in 1900 and 1902, respectively. During his plant explorations, Uchiyama collected numerous specimens which were investigated and studied by T. Nakai (Flora Koreana I and II and other publications) and H. $L{\acute{e}}veill{\acute{e}}$ later. Unfortunately all collection sites were simply described by Nakai in Romanized characters, so that it is difficult to pinpoint those sites using the current or the old Korean map. From this study, many locality names were reviewed based on his own plant specimens at TI and literatures, and those were listed as the order of his collection dates. Based on specimens deposited at TI, only ca. 200 specimens were confirmed, although 1,674 specimens were listed by Nakai. Among his collections, 2/3 of his collections were conducted in 1902 and among them 41 specimens were cited as type collections by Nakai.

• Journal of the Korean Institute of Telematics and Electronics
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• v.18 no.1
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• pp.51-56
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• 1981

A new I2L process for a high performance I2L structure is proposed. The modifiedstructure consists of a heavily doped extrinsic base and lowly doped intrinsic base where the collector regions are self-alignment with the intrinsic base regions. The proposed process untilizes spin-on sources as the diffusion sources and the self-alignment of collectors is achieved by using the hardened spin-on source as a diffusion mask. Test devices including a 13-stage ring oscillator have been fabricated by the proposed process on n/n+ silicon wafers with 6.5$\mu$m epitaxial layer. The maximum upward current gain of npn transistors is 8 for a three collector I2L cell. The speed-power product and minimum propagation delay for a one collector structure are 3.5 pJ and 50 ns, respectively.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.44-53
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• 1994

A study on the iron electrode which is a good material for alkaline battery because of its superior characteristics including high theoretical capacity density, low toxicity, low cost and inexhaustible supply was performed to develop high performance nickel-iron secondary battery. The characteristics of chrage-discharge reaction were examined by cyclic voltammetry technique SEM and XRD analysis. The capacity of the test electrodes was determined by the costant current charge-discharge method. It was found that the purity and particle size of iron material were the major determinant factors of electrode capacity. With the addition of $Na_2S$ into the electrolyte the capacity of electrode was increased about 20 % caused by the prevention of passivation and the increase of hydrogen overpotential. The stability and capacity of electrode were increased with the use of Ni-fibrex and foamed Ni collectors and also depended on the sintering temperature. The capacity of electrode was 350 mAh/g(0.2 C) which corresponded to 36% utility.

• Journal of the Korean Society for Library and Information Science
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• v.54 no.2
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• pp.179-195
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• 2020

This study searched for the status of medical Systematic Review(SR) publications in Korea and elsewhere for last 10 years, closely analyzing SR research papers by co-authors of Korean librarians. Through interviews with Korean librarians participating in SR, the activities, roles, and difficulties of these librarians were identified, and the results of the interviews helped explore new ways to promote collaboration in SR research. The result of the studied showed that the number of domestic and foreign SR studies has recently increased, and the number of cases where Korean librarians participated in SR research being officially credited as a co-author or acknowledgment source was also grow. The SR librarians in the Korean medical libraries were not only search experts, data collectors, and reference writers, but also did various activities such as designing search strategies, SR search records with complete reproducibility, and DB search tutorship. To promote SR support librarians participated in the interview suggested recruiting new librarians, retraining current librarians, and reformation courses in library and information science. As it is expected that the level of information demand of users and expectations for librarians would also increase in near future, SR librarians' activities and contributions seem to offer a guideline for academic library services that the others should pursue.

• Journal of the Korean Solar Energy Society
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• v.32 no.4
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• pp.43-50
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• 2012

Metal-metal oxide (M-M oxide) cermet solar selective coatings with a double cermet layer film structure were deposited on the Al-deposited glass substrate by using a directed current (DC) magnetron sputtering technology. M oxide (CrO and ZrO) was used as the ceramic component in the cermets, and Cr and Zr used as the metallic components. In addition, black Cr (Cr-$Cr_2O_3$ cermet) solar selective coatings were deposited on the Ni-plated Cu substrate by using a electroplating method for comparison. The thermal stability tests were carried out for performance evaluation of solar coatings. Reflectance measurements were used to evaluate both solar absorptance(${\alpha}$) and thermal emittance (${\epsilon}$) of the solar coatings before and after thermal testing by using a spectrometer. Optical properties of optimized cermet solar coatings were ${\alpha}{\simeq}0.94-0.96$ and ${\epsilon}{\simeq}0.1$ ($100^{\circ}C$). The results of thermal stability test of M-M oxide solar coatings showed that the Cr-CrO cermet solar selective coatings were more stable than the Zr-ZrO cermet selective coatings at temperature of both $400^{\circ}C$ in air and $450^{\circ}C$ in vacuum. The black Cr solar selective coatings were degraded in air at temperature of $400^{\circ}C$. The main optical degradation modes of these coatings were diffusion of metal atoms, and oxidation.

• Korean Journal of Plant Taxonomy
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• v.34 no.2
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• pp.87-96
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• 2004

Father, U. Faurie visited Korea (Busan, Incheon, Nampo, Pyongyang, Seoul, Wonsan, Mt. Geumgang of Gangwon-do, and Jeju-do) three times for his plant collections (1901, 1906, and 1907). During his plant explorations, Faurie collected many specimens which were investigated and studied by T. Nakai and H. L$\acute{e}$veill$\acute{e}$ later. Unfortunately all collection sites were simply described in his collection sites in Romanized character, so that it is difficult to pinpoint those sites using the current or old Korean map. From this study, many locality names were reviewed based on his own collections and literatures, and those were listed as the order of his collection dates.

• Composites Research
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• v.36 no.6
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• pp.416-421
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• 2023

Multifunctional composite materials capable of both load-carrying and energy functions are promising innovative candidates for the advancement of contemporary technologies owing to their relative feasibility, cost-effectiveness, and optimized performance. Carbon fiber (CF)-based structural batteries utilize the graphitic inherent structure to enable the employment of carbon fibers as electrodes, current collectors, and reinforcement, while the matrix system is an ion-conduction and load transfer medium. Although it is possible to enhance performance through the modification of constituents, there remains a need for a systematic design methodology scheme to streamline the commercialization of structural batteries. In this work, a bi-phasic epoxy-based ionic liquid (IL) modified structural battery electrolyte (SBE) was developed via thermally initiated phase separation. The polymer's morphological, mechanical, and electrochemical characteristics were studied. In addition, the interfacial shear strength (IFSS) between CF/SBE was investigated via microdroplet tests. The results accentuated the significance of considering IFSS and matrix plasticity in designing composite structural batteries. This approach is expected to lay the foundation for realizing smart structures with optimized performance while minimizing the need for extensive trial and error, by paving the way for a streamlined computational design scheme in the future.

• Korean Journal of Environment and Ecology
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• v.36 no.2
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• pp.150-164
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• 2022

The objective of this study is to analyze the biodiversity changes and characteristics of the benthic macroinvertebrate community in the Nakdong River with eight weirs, which was constructed as one of the Four Major River Restoration Projects from May to October 2020. The study also includes the analysis of changes in the major groups of benthic macroinvertebrates for about ten years, from 2010 to 2020. The surveys collected 97 species of benthic macroinvertebrates belonging to 83 genera, 52 families, 18 orders, five classes, three phyla, and 128.1 individuals/m². Chironomidae sp. and Tubificidae spp., which are pollutant indicators, dominated throughout the sections. The community analysis result shows the average dominant index and the diversity index of 0.62±0.20 and 1.87±0.63, respectively, and indicated the most stability of the freshwater ecosystem in the upper stream of the Nakdong River. The survey showed dominance by Chironomidae sp. at the center of the Nakdong River weir and the most unstable community in Chilgok and Gangjeong Goryeong weirs. The results of the community stability analysis showed a high distribution of the characteristic group I with high resilience and resistance and small distribution of characteristic group III with low resistance and resilience, indicating a very unstable condition of communities in the Nakdong River weir section. Predators were relatively abundant among the functional feeding groups (FFGs), whereas shredders, gathering-collectors, and filtering-collectors were relatively lower. Among the habitat orientation groups (HOGs), burrowers and climbers were dominant, indicating a wide distribution of groups in ecosystems with low dissolved oxygen. An endangered species level II of Macromia daimoji was found in Sangju and Nakdan weirs. The analysis results for 10 years from 2010 showed that the number of species and populations increased immediately after the dam construction but plummeted in 2016 and are now stabilizing. Chironomidae spp. has been dominant in all sections over the past 10 years, and they are currently maintained at a rate of about 50%. The EPT groups have decreased significantly since 2011, and the Plecoptera and Trichoptera of the group have not yet been restored. The population of Tubificidae spp. showed an increase after construction was completed in 2012 and drastically increased in 2015 and 2020. The species of Cristaria plicata, designated as endangered species level I, has not been observed since 2011 in Hapcheon Changnyeong weir. Moreover, Macromia daimoji was rarely observed in seven weirs until 2015, and it has been confirmed that the current distribution habitat has decreased rapidly.

• The Journal of Art Theory & Practice
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• no.7
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• pp.125-163
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• 2009

The artworks of Socialist Realism of the former Soviet Union, with the beginning of the 21st century, are gaining a new attention from art collectors. One reason for this might consist in the fact that relevant art pieces exemplify the ways in which they visualize ideas on the basis of their high-profile art tradition and also in which they integrate their utopian ideals with mysticism. These aspects of the Soviet art goes far beyond the wide-spread assumption that their art, as a means of propaganda, principally represents a political allegiance to the system. With Stalin coming into power in the 1930s, the artistic trend of Socialist Realism obtained a nationwide sympathy and support from people, giving birth to a new art which essentially corresponded to the demands of the political power. An official art current of the USSR over the period from the 1930s to 1950s, Socialist Realism was in tandem with the Communist commitment to the party and popularity, symbolizing a loyalty to the cause. It was thus characterized by plainness and lucidity so that ordinary people could gain easy access to art. Its salient feature, over an entire range of art, was an optimistic pursuit of a utopian dream. Therefore, it tallied with the popular sentiment for a Communist paradise, giving form to their beliefs in human agency working at the materialist world and also to such abstract concepts as force, fitness, and beauty by adding even mythical ideals. Its main subject matter includes harvest feasts of collective farms, imaginary socialist cities, grand marches of heroic laborers and in this way it served as a propaganda for a sacred utopia of socialist totalitarianism. On the other end of the spectrum, however, rose the second camp of art, which put an emphasis on bona-fide artistic activities of plastic art and on an artist's personal expression and freedom, as opposed to the surface optimism of Socialist Realism. Central to the Russian Avant Garde art, which prized the above-mentioned values, were Malevich's Geometric Abstraction and A. Rodchenko's Constructivism. Furthermore, in the transitional era of the late 20th century and the 21st century it was recognized that film art or electronic media art, rather than traditional genre of paintings, would function as a more efficient way of propaganda. These new genres were made possible by ridiculing the stereotypes of the Russian lifestyle and also by ignoring ethical or professional dimensions of artworks. That is, they reinvented themselves into a sort of field art, seemingly degrading the quality of artworks and transforming them into artifacts or simulacres in the very sense of post-modernism. The advent of the new era brought about the formation and occupation of pop culture of the younger generations, calling into question the idea of art as the class-determined. It also increased the attention to field art, which extensively found way to modern art centers, galleries, and exhibition projects. It can be stated that this was a natural outcome of human nature.