• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.11 no.4
• /
• pp.77-89
• /
• 2001

Recently, with the explosive growth of communication technologies, group oriented services such as teleconference and multi-player game are increasing. Access control to information is handled by secret communications with group keys shared among members, and efficient updating of group keys is vital to such secret communications of large and dynamic groups. In this paper, we employ (2,4)-tree as a key tree, which is one of height balanced trees, to reduce the number of key updates caused by join or leave of members. Especially, we use CBT(Core Based Tree) to gather network configurations of group members and reflect this information to key tree structure to update group keys efficiently when splitting or merging of subgroups occurs by network failure or recovery.

• Proceedings of the Korea Contents Association Conference
• /
• 2009.05a
• /
• pp.810-815
• /
• 2009

In recent years, embedded systems such as cellular phones, Portable Multimedia Player, intelligent appliance, automobile engine control are reshaping the way people live, work, and play. Thereby, applications for embedded systems become increasingly sophisticated and complicated, such embedded computing platforms must use real-time operating systems (RTOSs) with time determinism. These RTOSs must not only provide predictable services but must also be efficient and small in size and it's kernel services should also be deterministic by specifying how long each service call will take to execute. Having this information allows the application developers to better plan their real-time application software so as not to miss the deadline of each task. In this paper, we present the complete generalized algorithm using multi-dimensional methodology to determine the highest priority in the ready list with 2r levels of priorities for an arbitrary integer number of r.

• Korean Journal of Human Ecology
• /
• v.20 no.2
• /
• pp.391-400
• /
• 2011

Internet shopping malls for fashion products(e.g., apparel, cosmetics and accessory) may become a major player with a promising future because of its tremendous growth in e-commerce. In addition, the fashion market has been segmented by various types of shopping malls on the internet. For many types of internet shopping malls, literatures give us numerous types, such as general mall, specialty mall, open-market, mall-in-mall, department-mall, brand-mall, and a specialized category mall, etc. Although each mall specializes in different activities, a unified categorization with managerially meaningful implications has not been made. This paper aims to explore criteria of internet shopping malls based on previous research related to shopping mall types for fashion products. The results found that internet shopping malls for fashion products were classified based on physical space, openness of the mall, number of companies, method of profit, specialization of products, number of product categories, and brand products dealt with. Internet shopping mall for fashion products was classified into online malls versus online malls versus offline mall, open mall versus closed mall, single mall versus multi mall, retail-trade mall versus syndicated mall, general mall vs specialize mall, one-product category mall versus multi-product category mall, and brand mall versus non-brand mall. These findings could offer an important contribution in research and practice, and an insight into developing appropriate strategies for effective fashion shopping mall management related products.

• The Journal of the Korea Contents Association
• /
• v.10 no.1
• /
• pp.94-102
• /
• 2010

In recent years, embedded systems such as cellular phones, Portable Multimedia Player, intelligent appliance, automobile engine control are reshaping the way people live, work, and play. Thereby, services application to guarantee various requirements of users become increasingly sophisticated and complicated, such embedded computing platforms use real-time operating systems (RTOSs) with time determinism. These RTOSs must not only provide predictable services but must also be efficient and small in size. Kernel services should also be deterministic by specifying how long each service call will take to execute. Having this information allows the application designers to better plan their real-time application software so as not to miss the deadline of each task. In this paper, we present the complete generalized real-time scheduling algorithm using multi-dimensional methodology to determine the highest priority in the ready list with 2r levels of priorities in a constant time without additional memory overhead.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.12
• /
• pp.8933-8939
• /
• 2015

In this paper, we designed a multi humanoid robot control method for performing an exhibition that will maximize the efficiency and user convenience and implementation. In recent years, an increasing number of case and to take advantage of the robots in the field performances and exhibitions, plays, musicals, orchestra performances are also various genres. In concert with the existing small humanoid exhibition to source from outside by using a computer and MP3 player and play, while pressing the start button of communication equipment for the show to start the robot began performing with the zoom. Thus, due to the dual source and robot operation and synchronization does not work well is the synchronization of the start of the concert sound starting point of the robot and robot motion and sound are reproduced separately were frequently occurs when you need to restart the show. In addition, when the center of gravity or lose the robots who were present during the performance problems such as performance or intervene to restart the show. In order to overcome this, in this paper, Multi-small humanoid robot was designed to control the efficiency and the user of the GUI-based human interface S/W to maximize convenience, Zigbee communication to transmit a plurality of data in al small humanoid It was used. In addition, targeting a number of the small humanoid robot demonstrated the effectiveness and validity of the user's convenience by gender actual implementation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.7
• /
• pp.1657-1670
• /
• 2013

The increase in the number of music files in smart phone and MP3 player makes it difficult to find the music files which people want. So, Query-by-Singing/Humming (QbSH) systems have been developed to retrieve music from a user's humming or singing without having to know detailed information about the title or singer of song. Most previous researches on QbSH have been conducted using musical instrument digital interface (MIDI) files as reference songs. However, the production of MIDI files is a time-consuming process. In addition, more and more music files are newly published with the development of music market. Consequently, the method of using the more common MPEG-1 audio layer 3 (MP3) files for reference songs is considered as an alternative. However, there is little previous research on QbSH with MP3 files because an MP3 file has a different waveform due to background music and multiple (polyphonic) melodies compared to the humming/singing query. To overcome these problems, we propose a new QbSH method using MP3 files on mobile device. This research is novel in four ways. First, this is the first research on QbSH using MP3 files as reference songs. Second, the start and end positions on the MP3 file to be matched are estimated by using multi-layered perceptron (MLP) prior to performing the matching with humming/singing query file. Third, for more accurate results, four MLPs are used, which produce the start and end positions for dynamic time warping (DTW) matching algorithm, and those for chroma-based DTW algorithm, respectively. Fourth, two matching scores by the DTW and chroma-based DTW algorithms are combined by using PRODUCT rule, through which a higher matching accuracy is obtained. Experimental results with AFA MP3 database show that the accuracy (Top 1 accuracy of 98%, with an MRR of 0.989) of the proposed method is much higher than that of other methods. We also showed the effectiveness of the proposed system on consumer mobile device.

• The Journal of the Korean life insurance medical association
• /
• v.22
• /
• pp.121-137
• /
• 2003

현행 생명보험업계는 중복가입계약에 대한 정보교환제도를 시행함으로써 잠재적 위험에 대한 위험평가를 하고는 있으나 실제 언더라이팅 과정에서는 효율적인 활용을 못하고 있다. 따라서 언더라이팅 실무 입장에서 현행 정보교환제도의 문제점을 파악하고 각 보험회사가 취할 수 있는 효율적인 대응방안을 제시할 필요성이 대두되고 있다. 현행 정보교환제도의 문제점을 크게 몇가지로 나눌 수 있다. - 교환기준에 미달하는 다수의 계약건을 가입한 경우 위험평가 불가 - 위험평가상 고지의무에 충실한 계약자의 상대적 불리 - 정해진 기준과 다른 임의적 기준적용 등 선별적 자료교환으로 위험선택에서 배제된 잠재적 위험들의 계속적인 계약 및 지급 등 역선택 방조기능 - 실시간 반영된 정보부재 및 교환된 자료만으로 one-stop 위험평가를 할 수 없는 어려움 내재 - 정보교환에 대한 전체적 참여노력 부족 및 자기정보에 대한 방어와 자체 활용 이런 문제점들을 인식하고 이에 대한 효율적 대응방안을 제시해 본다. - 언더라이팅 측면에서 판매채널 다변화, 업무겸업화 둥 대외 환경변화에 따른 위험분석 및 평가, 위험분산을 위한 multi-player로서의 언더라이터 양성 필요 - 지급, 조사건의 분석 및 통계화 등 feed back 기능 강화통한 언더라이팅 활용 - 방문진단 통한 적부기능 활용 또는 모집자 사정평점제 등 언더라이팅 과정에서 활용할 수 있는 위험평가 자료축적 - 영업환경적 측면에서 고보장 상품의 경쟁적인 개발제한 - 정보교환제도 측면에서 정보교환 기준 변경 및 교환내용 추가 및 공동의 계약인수 guideline 필요 - 진단거절체, 표준미달체, 사절체 등 새로운 정보교환의 추진 필요 - 종합적인 피보험자의 정보를 획득할 수 있는 피보험자 종합정보의 데이터 구축 및 활용 효율적인 위험관리 외에도 각 보험회사별로 역선택 위험에 대한 심각성을 인식하고 업계간 정보교환에 적극적인 참여와 노력이 필요하며 잠재적 위험평가를 하는데 있어 계약자에게는 객관적 근거없이 불편을 갖지 않도록 언더라이팅 서비스하는 것 또한 중요하다. 지속적인 피보험자의 위험통계축적으로 잠재위험에 대한 보다 객관화된 위험평가를 할 수 있는 언더라이팅 기법을 체득함으로써 언더라이팅 경쟁력을 갖을 수 있다.

• Journal of Korea Game Society
• /
• v.15 no.2
• /
• pp.33-42
• /
• 2015

This study analyzes location based game focused on the figurative characteristics of mobility. The purpose of this analysis is to extend the understandings of game mobility from technical side toward rhetorical territory. Christian Metz's film theory is appropriate for analysis of the game which is visual and combinational text. According as research findings, structuralize 5-layered spatial maps. And this kind of multi-layering structure generates figurative operations. Adaptive mobility by metaphor, it reflects player's real world movement into the virtual space. Metonymy brings given mobility, it reflects character's movement through all of the virtual maps.

• The KIPS Transactions:PartD
• /
• v.11D no.4
• /
• pp.901-906
• /
• 2004

Client- server interaction in a massive multi-player online role-playing game(MMORPG) is usually made via network-message Passing. Since the game contents and elements in such MMORPGs are consistently evolved, messages need to be added, deleted, or modified accordingly. Therefore, game programmers are repeatedly required to write new programs or at least modify existing programs. The XML-based message definition system introduced in this paper facilitates the addition and modification of messages for game interaction ; it not only allows programmers to save a considerable amount of time for modifying existing messages or adding new messages but also relieves them of a serious burden of programming bugs. In addition, this system can be used for general client-server applications.

• Journal of Korea Game Society
• /
• v.15 no.5
• /
• pp.89-98
• /
• 2015

The artificial intelligence (AI) of Non-Player Companions (NPC), especially opponents, is a key element to adjust the level of games in game design. Smart opponents can make games more challenging as well as allow players for diverse experiences, even in the same game environment. Since game users interact with more than one opponent in most of today's games, collaboration control of opponent characters becomes more important than ever before. In this paper, we introduce a cooperative strategy based on the A* algorithm for enemies' AI in the Pac-Man game. A survey from 17 human testers shows that the levels with our collaborative opponents are more difficult but interesting than those with either the original Pac-Man's personalities or the non-cooperative greedy opponents.