• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.36 no.4
• /
• pp.385-390
• /
• 2023

In this paper, the 1,700 V level SiC-based power MOSFET device widely used in electric vehicles and new energy industries was designed, that is, a single trench gate power MOSFET structure and a double trench gate power MOSFET structure were proposed to analyze electrical characteristics while changing the design and process parameters. As a result of comparing and analyzing the two structures, it can be seen that the double trench gate structure shows quite excellent characteristics according to the concentration of the drift layer, and the breakdown voltage characteristics according to the depth of the drift layer also show excellent characteristics of 200 V or more. Among them, the trench gate power MOSFET device can be applied not only to the 1,700 V class but also to a voltage range above it, and it is believed that it can replace all Si devices currently applied to electric vehicles and new energy industries.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.6
• /
• pp.566-572
• /
• 2011

In recent semiconductor and FPD (Flat Panel Display) manufacturing processes, high clean-class delivery operation is required more and more for short working time and better product quality. Traditionally SLIM (Single-sided Linear Induction Motor) is widely used in the liner drive applications because of its simplicity in the rail structure. A magnetically levitated (Maglev) unmanned vehicle with SLIM traction, which is powered by a CPS (Contactless Power Supply) can be a high precision delivery solution for this industry. In this paper unmanned FPD-carrying vehicle, which can levitate without contacting the rail structure, is suggested for high clean-class FPD delivery applications. It can be more acceptable for the complex facilities composed with many processes which require longer rails, because of simple rail structure. The test setup consists of a test vehicle and a rounded rail, in which the vehicle can load and unload products at arbitrary position commanded through wireless communications of host computer. The experimental results show that the suggested vehicle and rail have reasonable traction servo and robust electromagnetic suspensions without any contact. The resolution of point servo errors in the SLIM traction system is accomplished under 1mm. The maximum gap error is ${\pm}0.25mm$ with nominal air gap length of 4.0mm in the electromagnetic suspensions. This type of automated delivery vehicle is expected to have significant role in the clean delivery like FPD glass delivery.

• Journal of Korean Society of Forest Science
• /
• v.83 no.2
• /
• pp.254-261
• /
• 1994

This study was conducted to investigate and interpret the stand structure of Korean Red pine (Pinus densiflora) stands in Kangwon province, so as to provide basics information for effective forest management. The results obtained in this study were as follows : 1. Number of trees distribution for each diameter class have left nonsymmetrical in Gosung districts, but symmetrical distribution in Pyungchang districts. 2. Height curve for D.B.H. Distribution becames liner shape in Pyungchang districts that more higher than Gosung districts. 3. Stand volume and number of trees per ha in Pyungchang districts are higher than Gosung districts. 4. D.B.H. growth increments during recent 5 years at large D.B.H. class has much lager than low D.B.H. class. 5. Total growth increments of D.B.H., height and volume in Pyungchang districts are or the higher than Gosung districts overtimes 15 years later.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.24 no.3
• /
• pp.353-360
• /
• 2010

Huang di's Four Classics introduces the first full-scale Yin-Yang theory. The ancient idea of Yin-Yang could be classified systematically throughout Huang di's Four Classics and make itself the cause of creation, movement, and variation. The Tao of essence and Reason-Law(理法) is a single 'One'(一) and completes the reality of Tao adopting Yin-Yang as an elementary. The elementary of Yin-Yang has rules and laws and then the Tao manifest itself through Yin-Yang. The features of Yin-Yang theory in Huang di's Four Classics are placed on the explanation of the structure of the universe embodied as class and system. The class and system are the structured worlds in the space based on the upper and lower sides Yin-Yang idea(上下陰陽觀). It means the system by Yin-Yang theory, corresponding to the flat structure of the Sky and the Earth mentioned in Gaitian theory, one of the ancient theory of the universe structure. By adopting Huang di's Four Classics' Tian-zhi Yin-Yang theory(天地陰陽論) and developing the class system in human bodies, The Hwangjenegyeng appreciates human bodies as a whole. In addition, by applying Four seasons Yin-Yang theory not only to human bodies but also to the space of Liu-he(六合) and the time of Four Seasons(四時), it developed Yin-Yang theory of Huang di's Four Classics more abundantly and embodied Yin-Yang theory in many fields including physiology, pathology, diagnostics, and prescriptions.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.24 no.4
• /
• pp.374-383
• /
• 2013

This paper presents a design for improvement of isolation characteristics by the inserted stub structure on ground plane of a handy terminal which is composed of a main antenna and a sub antenna covered LTE bandwidth. In order to compensate for a resonance length of proposed antenna and to realize a high isolation characteristic, a pair of stub was inserted and located on ground plane that currents from two antennas were converged. A simulated isolation characteristic of antenna without stub at the LTE class 13 band was about -5 dB, but its characteristics of proposed antenna with two stubs at uplink(777~787 MHz) and downlink(746~756 MHz) of the LTE class 13 band were about -12 dB and -15 dB, respectively. An average gain of a fabricated antenna with two stubs was observed about -2 dBi above and it showed good results with comparison of business condition that the average gain of commercial handy terminal has to appear -4 dBi above. The measured S-parameter characteristics and radiation patterns showed a reasonable agreement with the simulation results.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.22 no.3
• /
• pp.187-194
• /
• 2002

This study was carried out to investigate the ecological characteristics, forage value and similarity among the plant communities of the gazing pasture at Witzenhausen, Germany. Ten plant communities of the different grazing pasture were the Molinio-Arrhenatheretea that was named the class of plant sociological nomenclature. The forage value of the plant communities were ranged from 4.35 to 6.60 grade for roughage qualify. Hemicryptophyte of lift form and mesomorphic of anatomical structure were greately dominated in all the plant communities. The correlation coeffcient between class No. 3 and 4 of plant communities was highest by botanical composition. The clustering analysis by Euclidean distance showed that class No. 9 and 10 of plant communities were closely grouped as affected by the similar botanical composition.

• Journal of the Korean Society for Library and Information Science
• /
• v.54 no.3
• /
• pp.165-186
• /
• 2020

Although BIBFRAME is recognized as a new bibliographic standard that can replace the existing MARC structure, the vastness of the descriptive items shows many limitations to be applied in library communities. Thus this study proposed separating the descriptive levels of BIBFRAME as a way to enhance the applicability of BIBFRAME. The descriptive level of BIBFRAME was divided into three stages: core, standard, and detailed levels based on the bibliographic area of ISBD 2011. This separation was semantically implemented using RDF/RDFS syntax. The levels of description in BIBFRAME was defined as Class Granularity and Class Element, and the Property Relation was defined for the linkage between the Classes defined and the BIBFRAME. By applying this syntactic structure, the relationships between the BIBFRAME descriptive items separated by each descriptive level could be linked with each other. This approach is expected to ensure applicability in the creation and sharing of bibliographic data using BIBFRAME.

• Proceedings of the Korea Crystallographic Association Conference
• /
• 2002.11a
• /
• pp.4-4
• /
• 2002

PDZ domains bind to short segments within target proteins in a sequence-specific fashion. GRIP/ABP family proteins contain six to seven PDZ domains and interact via its sixth PDZ domain (class Ⅱ) with the C-termini of various proteins, including liprin-α. In addition the PDZ456 domain mediates the formation of homo- and heteromultimers of GRIP proteins. To better understand the structural basis of peptide recognition by a class Ⅱ PDZ domain and DZ-mediated multimerization, we determined the crystal structures of the GRIPI PDZ6 domain, alone and in complex with a synthetic C-terminal octapeptide of human liprin-α, at resolutions of 1.5 Å and 1.8 Å, respectively. Remarkably, unlike other class Ⅱ PDZ domains, Ile736 at αB5 rather than conserved Leu732 at αB1 makes a direct hydrophobic contact with the side chain of the Tyr at the -2 position of the ligand. Moreover, the peptide-bound structure of PDZ6 shows a slight reorientation of helix αB, indicating that the second hydrophobic pocket undergoes a conformational adaptation to accommodate the bulkiness of the Tyr's side chain, and forms an antiparallel dimer through an interface located at a site distal to the peptide-binding groove. This configuration may enable formation of GRIP multimers and efficient clustering of GRIP-binding proteins.

• Lingua Humanitatis
• /
• v.1 no.2
• /
• pp.161-178
• /
• 2001

This study investigates how Korean traditional family consciousness interacts with Korean industrialization in the 1970s. In Our Children, Lee Sun depicts a family's struggle within the turmoil brought about by rapid industrialization to escape from the ranks of the working class. It is well known that one of the consequences of industrialization was the breakup of the larger family structure into nuclear families, but Lee Sun presents Korea's industrialization in the 1970s in the light of the traditional Korean family culture before the breakup. In other words, he gives us a portrayal of Gemeinschaft in Gesellschaft in his description of the extended family's struggle to overcome the day-to-day pressures of modernization and urbanization. The novel presents three generations of a traditional extended family. The eldest son is portrayed as a knife, strong and sharp. His wife has a temporary job that she hopes to give up once they own a house, which symbolizes the family's escape from the working class. The relationship among the family members reveals the core aspects of the ideology governing traditional extended families: the husband is the despotic monarch of the household, solely responsible for the family's economy; the husband is the sky and the wife the earth; and children (the more the better) are expected to lead to stability, welfare, and prosperity. One curious aspect of this family relationship as portrayed by Lee Sun is the expectation that being the eldest son, who already is or will become the patriarch of the family, is the fastest way of reaching middle-class status. And, despite a slight reversal, the novel has a happy ending wherein the family's expectations are fulfilled without much suffering. This aspect should be considered in light of the revolutionary romantic idealism of the novels of the 1930s. The lack of suffering and the easy happy ending may be attributed to the fact that Korea's industrialization came about rapidly and radically, and therefore it is likely that Lee Sun was not able fully to appreciate the full costs of industrialization. This limitation calls for a deeper investigation into the social structure and class consciousness of the 1970s, and also a study of the intertextual relationship of Our Children with other novels of the time.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.08a
• /
• pp.71-71
• /
• 2011

Dye-sensitized solar cells (DSCs) have drawn great academic attention due to their potential as low-cost renewable energy sources. DSCs contain a nanostructured TiO2 photoanode, which is a key-component for high conversion efficiency. Particularly, one-dimensional (1-D) nanostructured photoanodes can enhance the electron transport for the efficient collection to the conducting substrate in competition with the recombination processes. This is because photoelectron colletion is determined by trapping/detrapping events along the site of the electron traps (defects, surface states, grain boundaries, and self-trapping). Therefore, 1-D nanostructured photoanodes are advantageous for the fast electron transport due to their desirable features of greatly reduced intercrystalline contacts with specified directionality. In particular, anodic TiO2 nanotube (NT) electrodes recently have been intensively explored owing to their ideal structure for application in DSCs. Besides the enhanced electron transport properties resulted from the 1-D structure, highly ordered and vertically oriented nanostructure of anodic TiO2 NT can contribute additional merits, such as enhanced electrolyte diffusion, better interfacial contact with viscous electrolytes. First, to confirm the advantages of 1-D nanostructured material for the photoelectron collection, we compared the electron transport and charge recombination characteristics between nanoparticle (NP)- and nanorod (NR)-based photoanodes in DSCs by the stepped light-induced transient measurements of photocurrent and voltage (SLIM-PCV). We confirmed that the electron lifetime of the NR-based photoanode was much longer than that of the NP-based photoanode. In addition, highly ordered and vertically oriented TiO2 NT photoanodes were prepared by electrochemical anodization method. We compared the photovoltaic properties of DSCs utilizing TiO2 NT photoanodes prepared by one-step anodization and two-step anodization. And, to reduce the charge recombination rate, energy barrier layer (ZnO, Al2O3)-coated TiO2 NTs also applied in DSC. Furthermore, we applied the TiO2 NT photoanode in DSCs using a viscous electrolyte, i.e., cobalt bipyridyl redox electrolyte, and confirmed that the pore structure of NT array can enhance the performances of this viscous electrolyte.