• KSII Transactions on Internet and Information Systems (TIIS)
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• 제3권2호
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• pp.163-177
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• 2009

The demand for services using digital technology is constantly increasing as new developments in digital consumer electronics and the Internet are made. This is especially true in terms of the demand for IPTV utilizing high speed Internet networks. Research on IPTV threats is important for facilitating financial transactions via IPTV and preventing illegal use or copying of digital content. Thus, this paper analyzes IPTV threats via the IPTV value chain. That is, the distribution system for IPTV service is analyzed along with the components of the value chain and corresponding IPTV security requirements or security technologies, in order to perform a threat analysis and research suitable for the IPTV service environment. This paper has a greater focus on the value chain of the IPTV business than the approach in previous research, in order to analyze security requirements and technologies that are more applicable to the business environment.

• Journal of Communications and Networks
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• 제14권6호
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• pp.692-702
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• 2012

Supporting quality of service (QoS) guarantees for diverse multimedia services are the primary concerns for WiMAX (IEEE 802.16) networks. A scheduling scheme that satisfies QoS requirements has become more important for wireless communications. We propose a downlink scheduling scheme called adaptive priority-based downlink scheduling (APDS) for providing QoS guarantees in IEEE 802.16 networks. APDS comprises two major components: Priority assignment and resource allocation. Different service-type connections primarily depend on their QoS requirements to adjust priority assignments and dispatch bandwidth resources dynamically. We consider both starvation avoidance and resource management. Simulation results show that our APDS methodology outperforms the representative scheduling approaches in QoS satisfaction and maintains fairness in starvation prevention.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.307-310
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• 2006

In this paper, we design a prototype service in Telematics environment for providing safety warning notification at crooked roads efficiently using wireless sensor network. Through this study, we 1) analyze several requirements to be satisfied in the services, 2) design and implement the service architecture based on the requirements.

• Journal of Communications and Networks
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• 제4권3호
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• pp.199-208
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• 2002

The downlink rate scheduling problem is considered for CDMA networks with multiple users carrying packets of heterogeneous traffic (voice/audio only, bursty data only or mixed traffic), with each type having its own distinct quality of service requirements. Several rate scheduling algorithms are developed, the common factor of which is that part of the decision on which users to serve is based on a function of the deadline of their head-ofline packets. An approach of Andrews et al., in which the basic Earliest-Deadline-First algorithm is studied for similar systems, is extended to result in better performance by considering a more efficient power usage and by allowing service of more than one user per timeslot if the power resources permit it. Finally, the performance of the proposed schemes is compared through simulations.

• 한국컴퓨터정보학회논문지
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• 제6권4호
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• pp.138-145
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• 2001

본 논문에서는 분산처리시스템에서 서버에 대한 작업의 서비스요구와 서버의 서비스율이 네트워크환경에 따라 모호성을 갖는 경우, 시스템의 성능을 평가할 수 있는 퍼지 폐쇄형 BCMP 큐잉네트워크모델을 제안하였다. 이 모델은 퍼지요소들을 처리할 수 있는 퍼지평균값분석방법을 사용하여 시스템성능을 평가할 수 있는 측도를 유도하였다. 이들의 유효함을 검증하기 위하여 제안한 모델에 작업의 서비스요구와 클라이언트의 수의 변화에 따른 성능평가를 시뮬레이션 하였고, 그 결과를 확인하였다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2014년도 추계학술대회
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• pp.591-594
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• 2014

농업 분야에서의 IT 영역 융합은 네트워크를 기반으로 자동제어 기술과 실시간 정보제공을 통해 곡물의 생산성 재고 및 품질 향상 방안을 기대하게 되었다. 유비쿼터스 환경하에 농업 분야에서의 IT 융합 서비스는 기존의 농작물 생산, 유통, 소비 분야에서의 어려움을 극복하는데 많은 장점을 제공하게 되었으며 ICT와 접목하여 새로운 서비스를 창출하게 되었다. 본 논문에서는 네트워크 기반에서의 유비쿼터스 환경에서 농업을 위한 서비스 표준기술 요구조건 을 제시한다.

• Current Photovoltaic Research
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• 제11권2호
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• pp.58-65
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• 2023

The expanding significance of energy storage (ES) technology is increasing the acceptability of power systems by augmenting renewable energy supply. To deploy such ES technologies, we must select the optimal technology that meets the requirements of the system and confirm the technical and economic feasibility of the business model based on it. Herein, we propose a method and tool for selecting the optimal ES technology and service suitable for meeting the requirements of the system, based on its performance characteristics. The method described in this study can be used to discover and apply various ES technologies and develop business models with excellent economic feasibility.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권4호
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• pp.726-747
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• 2013

In order to support a large number of mobile stations (MSs) with statistical multiplexing in cellular networks, a random access scheme is widely used for uplink (UL) bandwidth request (BR). In the design of a random access based BR scheme, there are two important requirements: short connection delay and diverse Quality of Services (QoSs) support. Such requirements are crucial for IMT-Advanced systems like IEEE 802.16m to provide various types of fourth generation (4G) data services. IEEE 802.16m provides advanced UL BR schemes for non-real time polling service (nrtPS) and best-effort (BE) service to meet the requirements of short connection time and multiple QoS level support. In order to provide short connection time and multiple QoS support, three-step and differentiated BR procedures are adopted. In this paper, a novel modelling of IEEE 802.16m contention based BR scheme is proposed that uses a 2-dimensional discrete time Markov chain. Both the short access delay three-step BR procedures and normal five-step BR procedure are considered in the model. Our proposed model also incorporates the IEEE 802.16m differentiated BR procedure. With the proposed model, we extensively evaluate the performance of IEEE 802.16m BR for two different service classes by changing QoS parameters, such as backoff window size and BR timer. Computer simulations are performed to corroborate the accuracy of the proposed model for various operation scenarios. With the proposed model, accurate QoS parameter values can be derived for the IEEE 802.16m contention-based BR scheme.

• Journal of Astronomy and Space Sciences
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• 제26권4호
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• pp.643-650
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• 2009

Korea Astronomy and Space Science Institute (KASI) has been developing one mobile and one stationary SLR system since 2008 named as ARGO-M and ARGO-F, respectively. KASI finished the step of deriving the system requirements of ARGO. The requirements include definitions and scopes of various software and hardware components which are necessary for developing the ARGO-M operation system. And the requirements define function, performance, and interface requirements. The operation system consisting of ARGO-M site, ARGO-F site, and Remote Operation Center (ROC) inside KASI is designed for remote access and the automatic tracking and control system which are the main operation concept of ARGO system. To accomplish remote operation, we are considering remote access to ARGO-F and ARGO-M from ROC. The mobile-phone service allows us to access the ARGO-F remotely and to control the system in an emergency. To implement fully automatic tracking and control function in ARGO-F, we have investigated and described the requirements about the automatic aircraft detection system and the various meteorological sensors. This paper addresses the requirements of ARGO Operation System.

• International journal of advanced smart convergence
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• 제9권3호
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• pp.227-231
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• 2020

Recently, the importance of user experience (UX) has been rapidly increasing. Its utilization is emphasized for development of systems, products, and services. User experience is widely used across industries including services, products, processes, society, and culture. Therefore, if it is unsatisfactory, it is likely to have a direct negative impact on the corresponding system, product, or service. The failure to analyze user experience causes significant damage to the project, which may lead to its failure or redevelopment; it is hence necessary to prioritize the verification of UX in the earliest stages of development. The requirements development stage, which is a preceding stage, is an appropriate stage for the verification of user experience because the identification of user needs is completed and prototypes can be implemented. In this paper, we proposed a systematic requirements development stage; it adds user experience verification activities to the requirements development stage, using the Honeycomb model, which is a widely used tool for verifying the overall UX. User experience verification was added to the existing requirements development activities, which consisted of three steps: model definition and requirements placement, discussions between external and internal stakeholders, and review by internal stakeholders. By easily validating the user experience through this systematic requirements development stage, we expect to minimize the damage to the project due to the failure of the user experience analysis and increase the possibility of success.