• Journal of information and communication convergence engineering
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• 제13권4호
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• pp.248-256
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• 2015

With the dramatic increase in mobile traffic in recent years, some of the limitations of mobility management frameworks have magnified. The current centralized mobility management (CMM) strategy has various problems, such as a suboptimal routing path, low scalability, signaling overhead, and a single point of failure. To overcome these weaknesses in the CMM strategy, the Internet Engineering Task Force has been discussing distributed mobility management (DMM) strategies. The fundamental concept of a DMM strategy is to distribute the mobility anchors closer to the users. While the distribution of mobility anchors results in low-cost traffic delivery, it increases the signaling cost. To reduce this higher signaling cost, we propose a new DMM strategy applying the pointer forwarding technique. The proposed strategy keeps the existing tunnels and extends the traffic path as much as possible. In this paper, we analyze the performance of the pointer forwarding-DMM strategy and discuss its pros and cons.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2000년도 추계학술발표논문집 (상)
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• pp.485-488
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• 2000

인터넷을 통한 웹 기반 교수-학습시스템은 상호작용 중진을 통한 학습자 위주의 교육환경으로 지속적인 변화를 해왔고, 그 결과 학습자는 시간과 공간의 제약에서 벗어나 다양한 교육정보를 접할 수 있는 기회를 가지게 되었다. 본 논문에서는 교사를 대상으로 하는 원격교육 시스템에 한정하여 시스템개발에서 운영에 이르기까지의 모든 과정에 대한 경제적, 교육적 효율성 확보를 목적으로 하였다. 따라서 시스템 개발에서는 주요 모듈의 컴포넌트화를 시도하여 재사용성 증대를 통한 설계 기간 및 비용의 감소를 이끌어내어 개발의 효율성을 높이고, 교육학적 기반으로 구성주의 원리를 적용함으로써 교육의 효율성을 최대로 끌어올릴 수 있도록 설계하였다.

• 전자공학회논문지
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• 제50권5호
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• pp.9-17
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• 2013

본 논문에서는 modular 대칭 설계에 대해 소개하고 이를 이용하여 Hadamard-Jacket 행렬의 modular 3/5가 존재한다는 것을 제시한다. 그리고 n차 5-modular Hadamard 행렬의 필요충분조건이 n≢3.7 (mod 10)와 n≢6,11 임을 증명한다. 특히 Hadamard-Jacket 추측(conjecture)에 대한 5-modular 버전을 구한다.

• Journal of information and communication convergence engineering
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• 제17권2호
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• pp.97-104
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• 2019

Distributed mobility management (DMM) does not use a centralized device. Its mobility functions are distributed among routers; therefore, the mobility services are not limited to the performance and reliability of specific mobility management equipment. The DMM scheme has been studied as a partially distributed architecture, which distributes only a packet delivery domain in combination with the software defined network (SDN) technology that separates the packet delivery and control areas. Particularly, a separated control area is advantageous in introducing a new service, thereby optimizing the network by recognizing the entire network situation and taking an optimal decision. The SDN-based mobility management scheme is studied as a method to optimize the packet delivery path whenever a mobile node moves; however, it results in excessive signaling processing cost. To reduce the high signaling cost, we propose a hybrid distributed mobility management method and analyze its performance mathematically.

• Journal of Information Processing Systems
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• 제15권1호
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• pp.100-115
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• 2019

Malicious code distribution on the Internet is one of the most critical Internet-based threats and distribution technology has evolved to bypass detection systems. As a new defense against the detection bypass technology of malicious attackers, this study proposes the automated tracing of malicious websites in a malware distribution network (MDN). The proposed technology extracts automated links and classifies websites into malicious and normal websites based on link structure. Even if attackers use a new distribution technology, website classification is possible as long as the connections are established through automated links. The use of a real web-browser and proxy server enables an adequate response to attackers' perception of analysis environments and evasion technology and prevents analysis environments from being infected by malicious code. The validity and accuracy of the proposed method for classification are verified using 20,000 links, 10,000 each from normal and malicious websites.

• Journal of Information Processing Systems
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• 제15권1호
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• pp.127-136
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• 2019

User-based and item-based approaches have been developed as the solutions of the movie recommendation problem. However, the user-based approach is faced with the problem of sparsity, and the item-based approach is faced with the problem of not reflecting users' preferences. In order to solve these problems, there is a research on the combination of the two methods using the concept of similarity. In reality, it is not free from the problem of sparsity, since it has a lot of parameters to be calculated. In this study, we propose a combining method that simplifies the combination equation of prior study. This method is relatively free from the problem of sparsity, since it has less parameters to be calculated. Thus, it can get more accurate results by reflecting the users rating to calculate the parameters. It is very fast to predict new movie ratings as well. In experiments for the proposed method, the initial error is large, but the performance gets quickly stabilized after. In addition, it showed about 6% lower average error rate than the existing method using similarity.

• Journal of Information Processing Systems
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• 제18권1호
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• pp.89-96
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• 2022

A novel multistage pulse jamming suppression algorithm was proposed to solve the anti-pulse jamming problem encountered in navigation receivers. Based on the characteristics of the short duration of pulse jamming and distribution characteristics of satellite signals, the pulse jamming detection threshold was derived. From the experiments, it was found that the randomness of pulse jamming affects jamming suppression. On this basis, the principle of the multistage anti-pulse jamming algorithm was established. The effectiveness of the anti-jamming algorithm was verified through experiments. The characteristics of the algorithm include simple determination of jamming detection threshold, easy programming, and complete suppression of pulse jamming.

• 전자통신동향분석
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• 제37권5호
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• pp.1-10
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• 2022

Digital trade rules are crucial in supporting the digital economy as the rules effectively reduce unnecessary trade barriers. This study introduces various approaches that major countries take regarding digital trade policies and rules. Comprehensive and Progressive Agreement for Trans-Pacific Partnership has introduced comprehensive rules on e-commerce, including binding articles on the free flow of information, location of computing facilities, and source code. More recent e-commerce provisions or digital trade agreements cover wider range of issues, from cyber security, artificial intelligence, and data innovation to electronic invoicing and payments. Multilateral negotiations on digital trade rules, including the World Trade Organization E-commerce Joint Statement Initiatives and Indo-Pacific Economic Framework, are in progress. Thus, countries involved are expected to respond to new digital trade issues with long-term strategies considering domestic policy objectives.

• International journal of advanced smart convergence
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• 제13권2호
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• pp.265-275
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• 2024

Smart factory is a remarkable development from traditional manufacturing systems to data-based smart manufacturing systems that can connect and process data continuously, collected from machines, production equipment to production and business processes, capable of supporting workers in making decisions or performing work automatically. Smart factory is the key and center of the fourth industrial revolution, combining improvements in traditional manufacturing activities with digital technology to help factories achieve greater efficiency, contributing to increased revenue and reduce operating costs for businesses. Besides, the importance of smart factories is to make production more quality, efficient, competitive and sustainable. Businesses in Vietnam are in the process of learning and applying smart factory models. However, the number of businesses applying the pine factory model is still limited due to many barriers and difficulties. Therefore, in this paper we conduct a survey to assess the needs and current situation of businesses in applying smart factories and propose some specific solutions to develop and promote application of smart factory model in Vietnamese businesses.

• 정보교육학회논문지
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• 제10권2호
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• pp.219-226
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• 2006

어노테이션(annotation)은 문서에서 개인의 의견, 정리, 요약 등을 표현하기 위한 주석을 의미한다. 따라서 전자문서에서도 어노테이션은 중요하게 사용되며 특히 전자 잉크(digital inking)릉 이용한 이동 단말기 환경에서 효과적으로 사용된다. 그러나 기존 연구에서는 휴대용 단말기 환경의 단점인 적은 디스플레이 공간을 전혀 고려하지 않기 때문에 어노테이션 작성 및 활용이 매우 불편하다. 따라서 본 논문에서는 전자펜과 이동식 단말기 환경을 고려한 어노테이션 모델 및 시스템을 제안한다. 제안 어노테이션 모델은 다양한 컨텍스트(context)를 고려하고 이에 기반한 어노테이션 마크업 언어를 정의한다. 본 모델은 다양한 어노테이션 타입 및 의미(semantic) 모델, 펜 기반 어노테이션의 자동 인식 및 영역 보정 기능 등을 고려하며, 이것을 기반으로 CAML(Context-based Annotation Markup Language)를 정의한다. 또한 본 모델을 이용하여 XML 기반의 전자책문서 및 단말기 환경을 고려한 어노테이션 시스템을 구현하고 그 활용 가능성에 대하여 살펴본다. 본 연구의 결과는 eLearning, Cyber-Class, IETM(Interactive Electronic Technical Manuals) 에서 적절히 응용 가능하다.