• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.625-627
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• 2005

사용자가 시간과 장소에 구애 받지 않고 컴퓨터를 자연스럽고 효율성 있게 사용할 수 있는 환경을 의미하는 유비쿼터스 컴퓨팅은 네트워크와 센서(Sensor), smart devices, 무선 통신과 smart middleware(UPnP(Universal Plug and Play), Jini, HAVi(Home Audio Video Interoperability) IEEE 1394, PLC (Power Line Communication) 등) 등을 기반으로 Smart Space를 만들 수 있다. 그러나 여러 종류의 가전제품들이 늘어나고 수많은 사용자들의 요구를 충족시키기엔 smart middleware의 단일 제어로는 처리가 불가능하여 본 논문에서는 이기종간의 미들웨어간의 상호작용을 위해 개발된 OSGi(Open Service Gateway Initiative) Spec. 3에서 제공하는 서비스 플랫폼(Service Platform)을 기반으로 사용자/디바이스 관리 및 분산 시스템 등의 취약점들을 보완하여 Smart Space상에서 효율적인 서비스 번들을 관리하기 위해 MASBM(Multi-Agent Service Bundle Manager)을 제안하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10a
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• pp.253-256
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• 2006

인터넷 보급화와 기술의 발달로 가정 내 가전기기들을 네트워크로 연결하여 서로의 정보를 공유한다. 분산 환경인 연결 동작을 지원하는 시스템을 홈 네트워크의 기술을 바탕으로 사이버 홈이라는 개념이 생겨나게 되었다. 그리고 가전기기들의 인터넷을 통하여 제어할 수 있는 기술들이 생겨났다. 로컬화 되던 가전기기들이 디지털화되고 이기종간 연결을 위해서 미들웨어를 필요하다. 미들웨어를 사용하지 않을 때에는 서로 다른 가전기기들을 연결하여 사용하려면 중간에 Converter를 설치해야만 하는 불편한 점을 미들웨어가 해소해주게 되었다. 미들웨어로 UPnP와 Jini등 다양한 기술들이 생겨났다. 본 논문은 아직 미들웨어의 표준화가 되지 확정 않은 시점에서 미들웨어 하나인 UPnP을 택하여 가정내에서 전자 액자 서비스를 구현하고 그것에 대한 효용성을 보이고자 한다.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3409-3416
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• 2023

Licensing the next-generation of nuclear reactor designs requires extensive use of Modeling and Simulation (M&S) to investigate system response to many operational conditions, identify possible accidental scenarios and predict their evolution to undesirable consequences that are to be prevented or mitigated via the deployment of adequate safety barriers. Deep Learning (DL) and Artificial Intelligence (AI) can support M&S computationally by providing surrogates of the complex multi-physics high-fidelity models used for design. However, DL and AI are, generally, low-fidelity 'black-box' models that do not assure any structure based on physical laws and constraints, and may, thus, lack interpretability and accuracy of the results. This poses limitations on their credibility and doubts about their adoption for the safety assessment and licensing of novel reactor designs. In this regard, Physics Informed Neural Networks (PINNs) are receiving growing attention for their ability to integrate fundamental physics laws and domain knowledge in the neural networks, thus assuring credible generalization capabilities and credible predictions. This paper presents the use of PINNs as surrogate models for accidental scenarios simulation in Nuclear Power Plants (NPPs). A case study of a Loss of Heat Sink (LOHS) accidental scenario in a Nuclear Battery (NB), a unique class of transportable, plug-and-play microreactors, is considered. A PINN is developed and compared with a Deep Neural Network (DNN). The results show the advantages of PINNs in providing accurate solutions, avoiding overfitting, underfitting and intrinsically ensuring physics-consistent results.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.3
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• pp.247-255
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• 2013

The flight control of re-entry vehicles poses a challenge to conventional gain-scheduled flight controllers due to the widely spread aerodynamic coefficients. In addition, a wide range of uncertainties in disturbances must be accommodated by the control system. This paper presents the design of a roll channel controller for a non-axisymmetric reentry vehicle model using the trajectory linearization control (TLC) method. The dynamic equations of a moving mass system and roll control model are established using the Lagrange method. Nonlinear tracking and decoupling control by trajectory linearization can be viewed as the ideal gain-scheduling controller designed at every point along the flight trajectory. It provides robust stability and performance at all stages of the flight without adjusting controller gains. It is this "plug-and-play" feature that is highly preferred for developing, testing and routine operating of the re-entry vehicles. Although the controller is designed only for nominal aerodynamic coefficients, excellent performance is verified by simulation for wind disturbances and variations from -30% to +30% of the aerodynamic coefficients.

• Journal of Power Electronics
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• v.17 no.6
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• pp.1658-1671
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• 2017

To address the inaccurate load demand sharing problems among parallel inverter-interfaced voltage-controlled distributed generation (DG) units in islanded microgrids (MGs) with different DG power ratings and mismatched feeder impedances, an enhanced voltage control scheme based on the active compensation of circulating voltage drops is proposed in this paper. Using the proposed strategy, reactive power and harmonic currents are shared accurately and proportionally without knowledge of the feeder impedances. Since the proposed local controller consists of two well-separated fundamental and harmonic voltage control branches, the reactive power and harmonic currents can be independently shared without having a remarkable effect on the amplitude or quality of the DGs voltage, even if nonlinear (harmonic) loads are directly connected at the output terminals of the units. In addition, accurate load sharing can also be attained when the plug-and-play performance of DGs and various loading conditions are applied to MGs. The effects of communication failures and latency on the performance of the proposed strategy are also explored. The design process of the proposed control system is presented in detail and comprehensive simulation studies on a three-phase MG are provided to validate the effectiveness of the proposed control method.

• The KIPS Transactions:PartD
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• v.11D no.5
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• pp.1095-1104
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• 2004

An electronic services which are based on Internet/Intranet business transactions are available to e-market places and get the broader business concepts. Component-based e-commerce technology is a recent trend towards resolving the e-commerce chanange at both system and ap-plication levels. The basic capabilities of component based systems should include the plug and play features at various granularities, interoper-ability across networks and mobility in various networking environments. E-business application developers are attempting to more towards web-service as a mechanism for developing component-based web-applications. Traditional process and development models are inadequately architectured to meet the rapidly evolving needs for the future of scalable web services. In this thesis, we focus specifically on the issues of e-business system architecture based on web service for establishing e-business system. We specifies and identifies design pattern for applying e-business domain in the context of multiple entities. We investigate prototype and frameworks to develope components for e-business application based suggested process. We present a worked example to demonstrate the behavior of Customer Authentication System(CAS) development with component and recommend process. Final]Y, we indicate and view on future directions in component-based development in the context of electronic business.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.10 no.4
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• pp.315-320
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• 2016

In this study, we developed a response time measuring apparatus for fencing which can use fencing athlete's own electric sword and connectors. The measuring apparatus designed to be connected to upper back of dummy body and it's position can be changed by spinning itself. And it operates like a closed circuit composed of dummy helmet, the apparatus, reel signal connection, connector and electric sword of athlete. This measuring apparatus can provide response time to athlete immediately which response time is measured from the time of indicating random signal of light and sound to the time of attacking dummy by athlete. we carried out pilot test for couch and athlete of national fencing team and could validate availability of this system.

• Journal of Digital Convergence
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• v.10 no.4
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• pp.265-270
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• 2012

The subscriber access network is cause of the bottleneck phenomenon because equipment and infrastructure were not originally designed for busty high-bandwidth traffic between MAN(Metro Area Network) and LAN(Local Area Network). Whether riding on shorter copper drops or optical fiber, Ethernet is emerging as the future broadband protocol of choice, offering plug and play simplicity, and low cost. EPON(Ethernet Passive Optical Network) combines point-to-multipoint optical infrastructure with low-cost high-bandwidth Ethernet. The future broadband access network will be a combination of point-to-point and point-to-multipoint Ethernet, optimized for transporting IP data, as well as time critical voice and video. EPON is being considered as a novel communications infrastructure for next-generation broadband access network for the convergence of low-cost Ethernet equipment and low-cost fiber infrastructure. But, EPON has a problem with duplex multimedia services. It is the insufficiency of bandwidth for upstream. Because all ONUs use a shared transmission media for upstream. In this paper, we addressed the problem of upstream bandwidth in EPONs. We presented a wavelength division EPON supporting QoS in the differentiated services framework.

• The Transactions of the Korea Information Processing Society
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• v.6 no.1
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• pp.182-192
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• 1999

The advance of the MPEG(Moving Picture Expert Group) and DSP(Digital Signal Processing) technologies lead the energence of the information appliances which are gradually digitalized and embedded the high-speed networking function. This paper proposes a CHANCE(Cost-effective Home ATM Network for the Consumer Electronics) protocol supporting the ATM-based high-speed networking between the information appliances within the home, and designs its specific functions including the network management and signalling function. The CHANCE protocol is basically based on the tree topology, and supports the plug-and-play function by using only the header field of the ATM cells. Unlike the existing ATM Warren protocol which uses the source routed addressing scheme to control the in-home devices from the Warren controller, the CHANCE protocol can support the inter-device controls as well as the controls from the CHANCE controller by using the switch and device identifier.

• International Commerce and Information Review
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• v.14 no.4
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• pp.563-582
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• 2012

In this paper, UPnP Network SaaS model has been studied. Currently, this model of UPnP Network and the trade mission is being used by outsourcing. From now on, the introduction of new trading systems and existing systems and the commercialization of this model as a UPnP network service connection should work. The future of UPnP network SaaS model will become commercially available software, commercial software can be accessed remotely via the Internet should be. Customer site activities must be managed from a central location. Application software architecture, pricing, partnerships, management should not include the character models. N should be the model. When used in small and medium enterprises have a very high value.