• Journal of IKEEE
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• v.24 no.1
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• pp.364-367
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• 2020

This paper presents the off-grid PV-ESS system of sequential voltage control method applied to OR logic gate. The conventional off-grid PV-ESS system with the low-voltage series connection has problems due to capacity expansion. To solve these problems, this paper proposes a noble PV-ESS system with high efficiency and low cost by applying sequential voltage control technique of the high-voltage series connection of analog circuit type. The input voltage of DC to AC inverter can be converted from the low-voltage by the combinations of series connection of the conventional cascaded 24V solar cell unit modules to the high-voltage of 384V in battery. The output voltage of the battery was 384V as the each input voltage of three phase DC to AC inverter, and the each output voltage of three phase 10kW DC to AC inverter is designed to be AC380V@60Hz as the line to line rms voltage value. To prove the validity of the theoretical analysis by PSIM simulation, the operating characteristics of sequential voltage control system with OR logic gate were confirmed through experiment results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.6
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• pp.1096-1101
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• 2004

By a tremendous expansion of Internet users, there's a number effects that cause the phenomenon of bottlenecked switching packets from routers. In order to tear down this problem, distributed system is applicable to almost every highly performed router systems. The main processor of distributed system, which manages routing table, commands IPC to delivering the forwarding table line processor that eases functionalities of the router. This makes the system having wired-speed forwarding function based on the hardware so that the performance of the network can be enhanced. Therefore, IPC, which assign a part of router, is necessary to exchange data smoothly and the constitution of IPC using Ethernet is widely adapted as a method for saving investment. In this paper, R-IPC mechanism improve the packet-processing rate over 10% through changed from defect of conventional Ethernet IPC, that is, 2 layer processing to TCP/IP or UDP/ IP into 1 layer processing for efficient packet forwarding.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.6
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• pp.1330-1336
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• 2014

QoS techniques and transmitted in real-time communication with the advancement of technology a variety of applications and services are available these days, mobile devices bogeuphwa LTE technology to the development of multimedia services with high quality can be realized. In order to satisfy this condition simply with a router with an increased bandwidth expansion by considering the increase in the routing table of the network scalability problems included. Burst traffic data to be distributed according to the environment is to be centered. To do this, the destination -based routing method to transmit the current paper -based (Source routing) routing settings are required. In this paper, published by the IETF, IP switching system based on standardized protocol Label Switching Multi-Protocol Label Switching (MPLS) network by using the existing Best Effect is difficult to guarantee QoS for multimedia transmission in MPLS network environment using optimized QoS guarantees to transmit the multicast.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.638-640
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• 2016

Recently, Humanity enter the super-connection generation that linking human and things as a result of the development ICT technologies. IoT technology is growing rapidly as a result of IoT technology appearance and development of smart device, technology expansion, the spread of smart sensors, spread diffusion of smart devices, construction of a variety of network. These techniques are applied to those having a mobility is growing importance of network technology. Real-time service and features, such as the accuracy of the data it became important. In order to implement the IoT will need to take into account IP, security, a lot of things such as a service model, but in this paper, want to discuss mobility, for the tracking technology of routing path for efficient service delivery of the host. Therefore, in this paper, the routing path that is currently study examined the tracking technology, we try to refer to routing method of the future of the mobile host.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.846-850
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• 2011

Nanocomposite anodes for rechargeable lithium battery are prepared by mixing tin and nickel nanoparticles via wet method and their electrochemical properties are examined. The Sn-Ni nanocomposite anode shows a maximum discharge capacity of 700 mAh $g^{-1}$ at the first cycle but very poor cycle performance. This means that the electrode porosity and the Ni component formed by the simple mixing of nanoparticles no longer play the role of buffering the volume expansion/contraction of Sn component during charge-discharge. To solve the cycle performance problem, a novel nanostructured Sn-Ni anode should be designed and tested.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.3
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• pp.291-302
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• 2005

Due to the importance of the parameter in structural response, the uncertain elastic modulus was located at the center of stochastic analysis, where the response variability caused by the uncertain system parameters is pursued. However when we analyze the so-called stochastic systems, as many parameters as possible must be included in the analysis if we want to obtain the response variability that can reach a true one, even in an approximate sense. In this paper, a formulation to determine the statistical behavior of in-plane structures due to multiple uncertain material parameters, i.e., elastic modulus and Poisson's ratio, is suggested. To this end, the polynomial expansion on the coefficients of constitutive matrix is employed. In constructing the modified auto-and cross-correlation functions, use is made of the general equation for n-th moment. For the computational purpose, the infinite series of stochastic sub-stiffness matrices is truncated preserving required accuracy. To demons4rate the validity of the proposed formulation, an exemplary example is analyzed and the results are compared with those obtained by means of classical Monte Carlo simulation, which is based on the local averaging scheme.

• Spatial Information Research
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• v.9 no.2
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• pp.353-368
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• 2001

Recently central and local governments developed a huge spatial database and system using full-scale Geographic Information System (GIS). But Inconsistent spatial data through duplicated database management drops off in efficiency and confidence of administration. It is difficult to share data because of their unique system and data type. Under these circumstances Ministry of Construction and Transportation (MOCT) has been carrying out Land Management Information System (LMIS) to computerize land administration and policy affairs and to implement land database such as law, spatial, attribute data. A prerequisite mission of LMIS is to develop open system for solving the problem of duplicated data management and data sharing and for supporting various computer environments such as hardware, software, network etc. The purpose of LMIS is to reuse the existing investment resources and to expand the existing system resources. Therefore the purpose of this study is to investigate a method of LMIS operation under the existing circumstances and expansion of the system in the future. To do this, Supporting various DBMS, GIS server, Distributing Computing Platform(Unix, NT Server) is needed. Especially LMIS need to be developed as open system with interoperability to get independence of application from various GIS servers.

• Journal of the Korean Society of Costume
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• v.61 no.8
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• pp.85-99
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• 2011

Geometrical figures have been used as artwork motifs from the ancient times to the present day. The area of fashion, being a part of modern art, is also largely influenced by geometry and geometrical shapes are being used as a motif for fashion design now more than ever before. However, studies about geometry in the fashion field are not yet done enough and further research is necessary. This research will therefore investigate the usages of round, square and triangular design in contemporary fashion. The main scope of this research is to look at the type of expression and analyze the intrinsic meanings of these shapes in modern fashion. This research will look profoundly into the general characteristics of these geometrical figures and analyze the effects and uniqueness found in the world collection introduced since 2007. As a result from this study, it was found that round and square objects were perceived in such a straightforward and positive way and these designs, when worn, really completed the final look. On the other hand, the triangular design was used mainly for spatial expansion and was interpreted in a more metaphorical, indirect and abstract way. The intrinsic meaning of round, square and triangle figures in contemporary fashion consists of the informal features that really steps out of the formative clothing structure. The topological changes that is formed from the interactive functions and the wholism that creates a new system through integration of the human body and clothing contains the intrinsic meaning of these geometrical figures. Based on the research results, the method of expression and the characteristics of modern day fashion's geometrical figures was able to be easily understood. This work provides the useful information on the development of fashion design and the extended interpretation of clothing structure.

• Journal of the Korean Society of Costume
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• v.63 no.6
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• pp.84-96
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• 2013

In researching the ontological status of fashion, a good grasp of fashion can decide the direction of fashion study. Fashion is sometimes considered an area of industry far from art from a point of view of purity of art, in spite of its aesthetic value and expression. However, art properties can be differentiated from the purity of art in modern aesthetics, and fashion properties which were the reason for that fashion to be considered as non-art can be affirmed as the same with properties of contemporary art properties. Therefore, the purpose of this study was to suggest the possibility that general properties of fashion can be accepted in the art arena through justifying art properties deviating from the purity of art. It can provide a boost to fashion's cultural status. For the research method, a literature review and case analysis were carried out through specialty publications related to art history, aesthetics, and fashion, regular publications and websites specializing in fashion, and art museums. Through the research, art properties deviated from the purity of art, which are; tactile sense, impermanence, dailiness, and commercial viability, were justified as being the same as fashion properties. These art properties were not general properties of fine art in modern aesthetics, but the ones occurring in contemporary arts. These properties, now present in contemporary art, can no longer disqualify fashion as a non-art.

• Steel and Composite Structures
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• v.1 no.4
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• pp.427-440
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• 2001

The growing use of unprotected or partially protected steelwork in buildings has caused a lively debate regarding the safety of this form of construction. A good deal of recent research has indicated that steel members have a substantial inherent ability to resist fire so that additional fire protection can be either reduced or eliminated completely. A performance based philosophy also extends the study into the effect of structural continuity and the performance of the whole structural totality. As part of the structural system, thermal expansion during the heating phase or contraction during the cooling phase in most beams is likely to be restrained by adjacent parts of the whole system or sub-frame assembly due to compartmentation. This has not been properly addressed before. This paper describes an experimental programme in which unprotected steel beams were tested under load while it is restrained between two columns and additional horizontal restraints with particular concern on the effect of catenary action in the beams when subjected to large deflection at very high temperature. This paper also presents a three-dimensional mathematical modelling, based on the finite element method, of the series of fire tests on the part-frame. The complete analysis starts with an evaluation of temperature distribution in the structure at various time levels. It is followed by a detail 3-D finite element analysis on its structural response as a result of the changing temperature distribution. The principal part of the analysis makes use of an existing finite element package FEAST. The effect of columns being fire-protected and the beam being axially restrained has been modelled adequately in terms of their thermal and structural responses. The consequence of the beam being restrained is that the axial force in the restrained beam starts as a compression, which increases gradually up to a point when the material has deteriorated to such a level that the beam deflects excessively. The axial compression force drops rapidly and changes into a tension force leading to a catenary action, which slows down the beam deflection from running away. Design engineers will be benefited with the consideration of the catenary action.