• Proceedings of the KIPE Conference
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• 2011.11a
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• pp.44-45
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• 2011

Research on photovoltaic (PV) generation is taking a lot of attention due to its infinity and environment-friendliness with decrease of price per PV cell. While central inverters connect group of PV modules to utility grid in which maximum power point tracking (MPPT) for each module is difficult, micro inverter is attached on each module so that MPPT for individual modules can be easily achieved. Moreover, energy generation and consumption efficiency can be much improved by employing direct current (DC) distribution system. In this paper, a digitally controlled PV micro converter interfacing PV to DC distribution system is proposed. Boundary conduction mode (BCM) is utilized to achieve zero voltage switching (ZVS) of active switch and eliminate reverse recovery problem of passive switch. A 120W prototype boost PV micro converter is implemented to verify the feasibility and experimental results show higher than 98% efficiency at peak power and 97.29% of European efficiency.

• Journal of Korea Multimedia Society
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• v.23 no.8
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• pp.1066-1074
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• 2020

High Level Architecture/Run-Time Infrastructure (HLA/RTI) is used to connect individual simulators on networks in order to interoperate heterogeneous simulators. In defense domain, Ship Air Defense Model (SADM) and Extended Air Defense Simulation (EADSIM) are two of most advanced simulation tools. To interoperate these SADM and EADSIM, this paper attempts to use HLA/RTI that helps to support a Composite Combat Mission Planning Simulation Environment (CCMPSE). The CCMPSE allows us to analyze a group of simulations for comprehensive and accurate experiments. For the first time, this paper analyzes guided missile simulations in EADSIM and SADM by comparing related simulation models in their parameters and considerations. It presents characteristics of these models in view of guided missile simulation perspectives. For the contributions of this paper, it provides insights to select guided missiles between SADM and EADSIM on the CCMPSE according to specific simulation purposes.

• Journal of Korean Library and Information Science Society
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• v.12
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• pp.97-132
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• 1985

Many educators and teacher-librarians have emphasized many times on the necessity and the educational value of the school library. But actually the necessity and the educational value of the school library is not recognized as the most important ones in the educational system. Therefore I tried to find out several ways on the development of the school library and the promotion of the teacher-librarian focusing on recognition of the necessity of school library. In order to develop the school library, it is necessary that the function of the school library should be maximized and transformed to effective system. I would like to suggest the following methods : 1) Transform the present school library into the school library media center. 2) Connect the running system S.L.M.C. to the curriculum of the school. 3) Emphasis of the reading education. 4) Guidance on the use of library. At last I studied on the definition, the legal status and the education of the teacher-librarian.

• Journal of Fashion Business
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• v.11 no.4
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• pp.173-182
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• 2007

The concept of wearable computer says to be able to connect to network freely without restrict of place and time through the garment that contain the wire and circuit. Thereby we can realize the ubiquitous circumstances. Wearable computer plays a role of center in controlling the electronic equipments under the ubiquitous circumstances and also it will become the main stream of the future computer development. The current wearable computer displays ugly appearance by attaching the parts of computer on the garment instead of installing them in the box. However, as size of computer components are minimized and it's speed is getting faster, it is certain that wearable computer will evolve as fashionable computer, still retaining garment's original purpose such as fitting and fasion even though the computer is being installed to the clothing. This study reviewed about components, future market share, developed goods, human-being becoming cyborg, application area, restrict and on-going research of wearable computer.

• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.721-724
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• 2000

This paper presents fingerprint authentication method based on minutiae quadrangle definded by neighboring two Delaunay triangles. In this method, we first make minutiae triangle through Delaunay triangulation which adaptively connect neighboring minutiae according to the local minutiae density distribution, and then use feature vectors in authentication which is extracted from the minutiae quadrangle formed by neighboring two minutiae triangles. This prevents the degradation of matching ratio caused by the errors in image processing or local deformation of the fingerprint, and we can authenticate more discriminately as this method reflects wider local area's topological features than the features extracted from the individual minutiae triangles. To evaluate the proposed algorithm's performance, experiment are conducted on 120 fingerprints, of which size is 256 ${\times}$ 364 with 500dpi resolution. Robust authentications are possible with low FRR.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.100-101
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• 2003

Gap junctions are membrane channels that directly connect the cytoplasm of neighboring cells, allowing the exchange of ions and small molecules. Two analogous families of proteins, the connexins and innexins are the channel-forming molecular vertebrates and invertebrates, respectively. Here, we present the molecular cloning and sequences analysis of novel innexiins, Binx2, expressed during Bombyx mori embryonic development. (omitted)

• Language and Information
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• v.7 no.1
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• pp.87-99
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• 2003

This paper investigates the role of input frequency in the acquisition of verb argument structures based on distributional information of a corpus of utterances derived from the English CHILDES database (MacWhinney 1993). It has been widely accepted that children successfully learn verb argument structures by innate language mechanisms, such as linking rules which connect verb meanings and its syntactic structures. In contrast, an approach to language acquisition called “statistical language learning” has currently claimed that children could succeed in acquiring syntactic structures in the absence of innate language mechanisms, making use of distributional properties of the input. In this paper, I evaluate the feasibility of the statistical learning in acquiring verb argument structures, based on distributional information about locative verbs in parental input. The naturalistic data allow us to investigate to what extent the statistical learning approach can and cannot help children succeed in learning the syntax of locative verbs. Based on the results of English database analysis, I show that there is rich statistical information for learning the syntactic possibilities of locative verbs in parental input, despite some limitations in the statistical learning approach.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.63-68
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• 2002

ADC(Automatic Discharge Connector) is commonly used for the easy maintenance of the submersible pumps. However, the small gap between the flange of the base plate and that of the pipe due to the head rise, the flow momentum change and the mis-installation makes leakage flow that may be a great loss to the pumping system. In this study, the performance degradation was predicted with the simple leakage flow model through the gap. The newly developed ADC was tested and the leakage performance was compared with the old one and also no-leakage piping system. The newly developed ADC reduced the leakage flow in a satisfactory way in comparison with the old model.

• Journal of electromagnetic engineering and science
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• v.5 no.1
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• pp.14-20
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• 2005

In this paper, a technique is presented for broadbanding the bow-tie slot antenna fed by a CPW(coplanar waveguide). The bandwidth performance of existing bow-tie slot designs is greatly enhanced by optimizing the slot shape and properly adjusting the characteristic impedance of the coplanar waveguide feeding the slot. To connect the 50-ohm input coaxial line to the CPW feed line, a linear taper in the CPW is employed. The designed antenna shows a 3.5 $\~$ 10.0 GHz impedance bandwidth, a 3.5 $\~$ 6.0 GHz pattern bandwidth, and a 5.5 $\~$ 7.5 dBi gain over 3.5 $\~$ 6.0 GHz. Above 6.0 GHz, the antenna radiation pattern appreciably deviates from the typical dipolar pattern.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.4
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• pp.849-853
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• 2012

Generally, it is not easy to learn guitar fingering for beginner. In this paper, therefore, we attach LED to flat board of guitar to more easily teach the beginner and also implement LED control system that can connect ATmega 128 in order to drive LED attached to guitar. The guitar's flat board is connected with ATmega 128 as communication method of Zigbee. We also develop UI that easily can be learned code and playing for guitar, programmed by guitar fingering and perform the research for guitar fingering using LED.