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Abstract. The mobile devices have gained much functionality and intelligence with the growth of network technologies, the abundance of network resources, and the increase of various services. At the same time they are also becoming... more
Abstract. The mobile devices have gained much functionality and intelligence with the growth of network technologies, the abundance of network resources, and the increase of various services. At the same time they are also becoming complicated and related problems to services and resources of mobile devices frequently occur. Since it is not easy for the manufacturers to completely remove the software errors of the mobile devices before they sell them, the users face inconvenience caused by them and the credibility of the manufacturers also decreases. So far, no definitive method has been given to debug software errors of the sold mobile devices. In this paper, we propose a debugging method to find and correct the software errors of the sold mobile devices based on the Open Mobile Alliance (OMA) Device Management (DM) standard. We define the managed objects (MOs) for composing the execution image and design the management operations for collecting MOs at the central server. We presen...
모바일 네트워크와 서비스의 발전으로 인해서 사용자들이 사용하는 모바일 단말기의 기능도 다양해지고 시스템도 복잡해지고 있다. 그러나 사용자는 항상 좀 더 편하고 신뢰성 있는 서비스를 받기를 원한다. 이러한 요구사항을 충족시키기 위해서 나온 것이 모바일 단말 관리 기술이다. OMA (Open Mobile Alliance) DM (Device Management) 작업 그룹 (Working Group)에서는 이러한 요구사항을... more
모바일 네트워크와 서비스의 발전으로 인해서 사용자들이 사용하는 모바일 단말기의 기능도 다양해지고 시스템도 복잡해지고 있다. 그러나 사용자는 항상 좀 더 편하고 신뢰성 있는 서비스를 받기를 원한다. 이러한 요구사항을 충족시키기 위해서 나온 것이 모바일 단말 관리 기술이다. OMA (Open Mobile Alliance) DM (Device Management) 작업 그룹 (Working Group)에서는 이러한 요구사항을 해결하기 위해서 단말 관리 기술에 대한 표준을 제정하고 있다. 이를 통해서 단말기의 원격 관리 기술에 대한 것은 많이 연구되고 있지만, 이 방법을 통해서 관리자가 수많은 단말기들을 관리하기에는 비효율적이다. 본 연구에서는 자율 컴퓨팅(Autonomic Computing) 개념을 적용하여 재사용 가능한 단말 관리 컴포넌트를 정의하고 활용한 단말기를 위한 자율 관리 시스템 (Autonomic Management System)인 AutoMO (Autonomic Mobile Device Management System)를 소개한다. 본 논문에서는 AutoMO 의 구조에 대해 설계한 것과 사례 연구로서 소프트웨어 리셋 진단 방법을 적용한 단말기 관리 방법의 예를 통해 설계를 검증한 결과를 제시한다.
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ABSTRACT Electron temperature profile of the first plasma on KSTAR has been estimated by the measurement of electron cyclotron emission employing a heterodyne radiometer. The Hot-Cold method was used for absolute calibration.
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We developed a new multi-view camera system composed of 9 cameras for capturing multi-view images and utilizing them in research and exhibition. The system is composed of cameras, rig, convergence controller, LANC signal controller, IEEE... more
We developed a new multi-view camera system composed of 9 cameras for capturing multi-view images and utilizing them in research and exhibition. The system is composed of cameras, rig, convergence controller, LANC signal controller, IEEE 1394 signal interface. And, we made a control program that can manage a record function and other various camera parameters at PC. By this program, we can shoot multi-view scenes manipulating each element camera independently or all 9 cameras totally. After the capturing, we transform the image into the glass-less multi-view display format, and then we can enjoy natural multi-view images at lenticular display.
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Research Interests: Computer Science, Distributed Computing, Complexity Theory, Service Design, Network Management, and 15 moreFuture Internet, Computer Network, Quality of Service, Communications networks, Internet Computing, Integrated Management, Network Architecture, Virtual Networks, Data Model, Scalability, Compatibility, Service Architecture, Internet, Communications, and Telecommunication Services
Abstract This article presents a numerical analysis of chemist flow in a discrete fractured system using 3D discrete fracture network, automated quadrilateral meshing, and streamline routing. The trajectories of chemists are visualized by... more
Abstract This article presents a numerical analysis of chemist flow in a discrete fractured system using 3D discrete fracture network, automated quadrilateral meshing, and streamline routing. The trajectories of chemists are visualized by OpenGL. Non-reactive masses are transported between two wells and then the main flow patterns are examined. The non-reactive chemists move selectively along intersecting lines or fracture planes in the direction of decreasing pressure gradient. The more heterogeneous the system is, the more severe the channeling occurs. A small region of one fracture comes into being flowing zone while only 30∼40% of all fractures affect the transport of solutes similar with a real heterogeneous case.
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IPTV is emerging as a new service that can be very lucrative for telecommunication service providers. In addition, work is progressing to make IPTV an entertainment platform that can replace traditional TV for customers. Guaranteeing... more
IPTV is emerging as a new service that can be very lucrative for telecommunication service providers. In addition, work is progressing to make IPTV an entertainment platform that can replace traditional TV for customers. Guaranteeing service quality is one of the most important factors to make IPTV services successful. For this, an IPTV service provider and a customer make a contract that uses specific quality indicators in a Service Level Agreement (SLA). To efficiently manage and guarantee SLAs, a method is required that can manage all hierarchical performance indicators from raw device level performance indicators to key quality indicators. In this paper, we analyze various IPTV performance indicators from various standard organizations and suggest an IPTV performance indicator hierarchy by extending the DEN-ng information model. Then, we propose an architecture that uses an ontology and Semantic Web Rule Language to manage SLAs, and more specifically, to detect SLA violations. The proposed architecture is implemented and tested using a simple scenario. The test results showed a possibility that the architecture can be used for detecting SLA violations.
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Research Interests: Fuzzy Logic, Network Management, OFDM, Noise, Quality of Service, and 3 moreWimax, FAST, and Throughput
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... Development and testing of an SNMP-based integrated management system for heterogeneous power line communication networks Chang-Keun Park1, Joon-Myung Kang2*, Mi-Jung Choi3, James Won-Ki Hong2, Yong-Hun Lim4, Seongho Ju4 and Moon-Suk... more
... Development and testing of an SNMP-based integrated management system for heterogeneous power line communication networks Chang-Keun Park1, Joon-Myung Kang2*, Mi-Jung Choi3, James Won-Ki Hong2, Yong-Hun Lim4, Seongho Ju4 and Moon-Suk Choi4 ...
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In this paper, we present an autonomic management method to provide personalized handover decisions for customized mobility management in heterogeneous wireless networks. A handover decision is a significant problem, especially in a... more
In this paper, we present an autonomic management method to provide personalized handover decisions for customized mobility management in heterogeneous wireless networks. A handover decision is a significant problem, especially in a heterogeneous network environment. This is exacerbated when the goal is to provide personalized services for mobile users. Personalized handover decisions should not only consider received signal strength, which is a traditional handover decision factor, but also context information, user preferences, user profiles, and other non-functional requirements. We present two metrics for evaluating access points: access point acceptance value and access point satisfaction value. Our algorithm uses a combination of functional and non-functional metrics to select the access point that has the maximum satisfaction value. In our simulation study, we show that our decision algorithm is better than other decision algorithms in terms of end user satisfaction.
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The computation of good and optimal handover decisions is a significant problem in a heterogeneous network environment. This is exacerbated when the goal is to provide personalized services for mobile users as opposed to generic device... more
The computation of good and optimal handover decisions is a significant problem in a heterogeneous network environment. This is exacerbated when the goal is to provide personalized services for mobile users as opposed to generic device metrics such as received signal strength. Personalized handover decisions should not only consider received signal strength, but also context information, user preferences, and other non-functional requirements. In this paper, we propose a novel autonomic management method for personalized handover decisions to satisfy end users’ demands in heterogeneous wireless networks. We define two objective metrics for evaluating specific access points: access point acceptance value and access point satisfaction value.
As mobile devices and functionalities have increased and become intelligent, many related problems have occurred. Especially, the degraded quality of service caused by the shadow area has given the end-users much inconvenience. In... more
As mobile devices and functionalities have increased and become intelligent, many related problems have occurred. Especially, the degraded quality of service caused by the shadow area has given the end-users much inconvenience. In addition, the credibility of the service providers, the network operators, and the manufacturers of the mobile devices have also decreased. In order to solve these problems, we need to monitor the radio frequency (RF) signal related information such as the received signal strength (RSS) for finding the shadow areas. So far, no appropriate method has been given. In this paper, we propose a RF signal monitoring method for the quality of service (QoS) improvement based on the Open Mobile Alliance (OMA) Device Management (DM) standard. We have defined the management objects (MOs) for finding the shadow areas and design the management operations for collecting the MOs at the central server. We have developed based on MOs and the management operations. We also present the result of the performance evaluation of our proposed management operations.
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Today, mobile devices are being used for various applications such as making voice/video calls, browsing Internet and so on. The operating time and battery consumption spent in those activities affect the battery life of mobile devices.... more
Today, mobile devices are being used for various applications such as making voice/video calls, browsing Internet and so on. The operating time and battery consumption spent in those activities affect the battery life of mobile devices. In this paper, we propose a method for predicting the battery lifetime of mobile devices based on usage patterns. We define the possible states of mobile devices based on their operating functions and develop a method of predicting battery lifetime based on average battery consumption and duration of each state.
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In the last decade, networks have evolved from simple data packet forwarding to platforms that support complex multimedia services, such as network-based personal video recording and broadcast TV. Each of these services has significant... more
In the last decade, networks have evolved from simple data packet forwarding to platforms that support complex multimedia services, such as network-based personal video recording and broadcast TV. Each of these services has significant quality demands: they are very sensitive to packet loss and jitter, and require a substantial amount of bandwidth. As the quality perceived by the end user gives the most accurate view on the streamed service quality, operators are increasing their focus on this type of metric, commonly described as Quality of Experience. This paper presents the design of a Quality of Experience information model that defines important metrics for measuring service quality. Based on these metrics, we define a novel control loop that represents the relationships among Quality of Experience, the Customer, and network services.
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The mobile devices have gained much functionality and intelligence with the growth of network technologies, the abundance of network resources, and the increase of various services. At the same time they are also becoming complicated and... more
The mobile devices have gained much functionality and intelligence with the growth of network technologies, the abundance of network resources, and the increase of various services. At the same time they are also becoming complicated and related problems to services and resources of mobile devices frequently occur. Since it is not easy for the manufacturers to completely remove the software errors of the mobile devices before they sell them, the users face inconvenience caused by them and the credibility of the manufacturers also decreases. So far, no definitive method has been given to debug software errors of the sold mobile devices. In this paper, we propose a debugging method to find and correct the software errors of the sold mobile devices based on the Open Mobile Alliance (OMA) Device Management (DM) standard. We define the managed objects (MOs) for composing the execution image and design the management operations for collecting MOs at the central server. We present a system that we have developed based on the MOs and the management operations. We also present how to debug software errors with the execution image and JTAG debugger.
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Power Line Communication (PLC) is an evolving communication network technology using the existing power lines and enables to provide the automatic meter reading service, high-speed Internet service as well as home networking service. As... more
Power Line Communication (PLC) is an evolving communication network technology using the existing power lines and enables to provide the automatic meter reading service, high-speed Internet service as well as home networking service. As the use of PLC network and their applications increase, we need to manage the resources of PLC networks efficiently. Major PLC chipset and modem vendors are trying to provide network management solutions, but they are only specific solutions. It is necessary to provide a general PLC network management solution for PLC networks comprised of PLC devices from heterogeneous vendors. In this paper, we propose a PLC network management system called i-NetMSuite4PLC. We also propose a common PLC MIB (Management Information Base) based on some existing PLC MIBs. We present the design and implementation of the system.