• Title/Summary/Keyword: computer science

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Concurrency Control and Consistency Maintenance of Cached Spatial Data in Client-Server Environment (클라이언트-서버 환경에서 캐쉬된 공간 데이터의 동시성 제어 및 일관성 유지 기법)

  • Shin, Young-Sang;Hong, Bong-Hee
    • Journal of KIISE:Databases
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    • v.28 no.3
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    • pp.512-527
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    • 2001
  • In a client-server spatial database, it is desirable to maintain the cached data in a client side to minimize the communication overhead across a network. This paper deals with the issues of concurrency and consistency of map updates in this environment. A client transaction to update map data is an interactive work and takes a long time to complete it. The map update in a client site may affect the other sites'updates because of dependencies between spatial data stored at different sites. The concurrent updates should be propagated to the other clients as well as the server to keep the consistency of map replicated in a client cache, and also the communication overhead of the update propagation should be minimized not to lose the benefit of caching. The newly proposed cache region locking with CR lock and CX lock controls the update dependency due to spatial relationships. CS lock and COD lock are suggested to use optimistic detection-based approaches for guaranteeing the consistency of cached client data. The cooperative update protocol uses these extended locking primitives and Spatial Relationship-based 2PC (SR-based 2PC). This paper argues that the concurrent updates of cached client spatial data can be achieved by deciding on collaborative updates or independent updates based on spatial relationships.

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An Efficient Scheme of Performing Pending Actions for the Removal of Datavase Files (데이터베이스 파일의 삭제를 위한 미처리 연산의 효율적 수행 기법)

  • Park, Jun-Hyun;Park, Young-Chul
    • Journal of KIISE:Databases
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    • v.28 no.3
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    • pp.494-511
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    • 2001
  • In the environment that database management systems manage disk spaces for storing databases directly, this paper proposes a correct and efficient scheme of performing pending actions for the removal of database files. As for performing pending actions, upon performing recovery, the recovery process must identify unperformed pending actions of not-yet-terminated transactions and then perform those actions completely. Making the recovery process identify those actions through the analysis of log records in the log file is the basic idea of this paper. This scheme, as an extension of the execution of transactions, fuzzy checkpoint, and recovery of ARIES, uses the following methods: First, to identify not-yet-terminated transactions during recovery, transactions perform pending actions after writing 'pa_start'log records that signify both the commit of transactions and the start of executing pending actions, and then write 'eng'log records. Second, to restore pending-actions-lists of not-yet-terminated transactions during recovery, each transaction records its pending-actions-list in 'pa_start'log record and the checkpoint process records pending-actions-lists of transactions that are decided to be committed in 'end_chkpt'log record. Third, to identify the next pending action to perform during recovery, whenever a page is updated during the execution of pending actions, transactions record the information that identifies the next pending action to perform in the log record that has the redo information against the page.

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Ontology-based Automated Metadata Generation Considering Semantic Ambiguity (의미 중의성을 고려한 온톨로지 기반 메타데이타의 자동 생성)

  • Choi, Jung-Hwa;Park, Young-Tack
    • Journal of KIISE:Software and Applications
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    • v.33 no.11
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    • pp.986-998
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    • 2006
  • There has been an increasing necessity of Semantic Web-based metadata that helps computers efficiently understand and manage an information increased with the growth of Internet. However, it seems inevitable to face some semantically ambiguous information when metadata is generated. Therefore, we need a solution to this problem. This paper proposes a new method for automated metadata generation with the help of a concept of class, in which some ambiguous words imbedded in information such as documents are semantically more related to others, by using probability model of consequent words. We considers ambiguities among defined concepts in ontology and uses the Hidden Markov Model to be aware of part of a named entity. First of all, we constrict a Markov Models a better understanding of the named entity of each class defined in ontology. Next, we generate the appropriate context from a text to understand the meaning of a semantically ambiguous word and solve the problem of ambiguities during generating metadata by searching the optimized the Markov Model corresponding to the sequence of words included in the context. We experiment with seven semantically ambiguous words that are extracted from computer science thesis. The experimental result demonstrates successful performance, the accuracy improved by about 18%, compared with SemTag, which has been known as an effective application for assigning a specific meaning to an ambiguous word based on its context.

An Authentication and Handoff Mechanism using AAA and HMIPv6 on NEMO Environment (이동 네트워크(NEMO)에서 HMIPv6를 적용한 AAA 인증 방안 연구)

  • Choi, Kyung;Kim, Mi-Hui;Chae, Ki-Joon
    • The KIPS Transactions:PartC
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    • v.16C no.2
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    • pp.165-182
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    • 2009
  • Mobile IPv6 spends considerable bandwidth considering that its signal volume is proportional to the mobile and also it should be strengthened to support the binding signal volume, the traffic, and effective mobility. So, the study in NEMO(Network Mobility), an extended version of Mobile IPv6, has been conducted. NEMO provides its mobility by putting several mobiles and more than one portable router into one unit called as mobile network. Because nodes access Internet via the portable router at this time, it receives transparency without any additional work and that much reduces binding signal while solving binding storm. By supporting mobility, NEMO is able to have various mobile structures which realize several networks hierarchically and it is necessary to improve its safety and security by authenticating among the upper networks or the lower ones while moving. Also, it is extremely required to begin a study in the device to improve efficiency accompanied with mobility, which is executed by the fast hand-off as well as the safe authentication. For those reasons, this paper not only classifies various NEMO mobile scenarios into 7 ways, but also provides AAA authentication of each scenario, the authentication through the safety authentication and fast handoff authentication using F+HMIPv6 and the way to reduce both signaling volume and packet delays efficiently during the handoff.

Difference of Facial Skin Temperature Responses between Fear and Joy (공포와 기쁨 정서 간 안면온도 반응의 차이)

  • Eum, Yeong-Ji;Eom, Jin-Sup;Sohn, Jin-Hun
    • Science of Emotion and Sensibility
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    • v.15 no.1
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    • pp.1-8
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    • 2012
  • There have been many emotion researches to investigate physiological responses on specific emotions with physiological parameters such as heart rate, blood volume flow, and skin conductance. Very few researches, however, exists by detecting them with facial skin temperature. The purpose of present study was to observe the differences of facial skin temperature by using thermal camera, when participants stimulated by monitor scenes which could evoke fear or joy. There were totally 98 of participants; undergraduate students who were in their adult age and middle, high school students who were in their adolescence. We measured their facial temperature, before and after presenting emotional stimulus to see changes between both times. Temperature values were extracted in these regions; forehead, inner corners of the eyes, bridge of the nose, end of the nose, and cheeks. Temperature values in bridge and end of the nose were significantly decreased in fear emotion stimulated. There was also significant temperature increase in the area of forehead and the inner corners of the eyes, while the temperature value in end of the nose decreased. It showed decrease in both stimulated fear and joy. These results might be described as follows: When arousal level going up, sympathetic nervous activity increases, and in turn it makes blood flow in peripheral vessels under the nose decrease. Facial temperature changes by fear or joy in this study were the same as the previous studies which measured temperature of finger tip, when participants experiencing emotions. Our results may help to develop emotion-measuring techniques and establish computer system bases which are to detect human emotions.

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Korean Emotion Vocabulary: Extraction and Categorization of Feeling Words (한국어 감정표현단어의 추출과 범주화)

  • Sohn, Sun-Ju;Park, Mi-Sook;Park, Ji-Eun;Sohn, Jin-Hun
    • Science of Emotion and Sensibility
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    • v.15 no.1
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    • pp.105-120
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    • 2012
  • This study aimed to develop a Korean emotion vocabulary list that functions as an important tool in understanding human feelings. In doing so, the focus was on the careful extraction of most widely used feeling words, as well as categorization into groups of emotion(s) in relation to its meaning when used in real life. A total of 12 professionals (including Korean major graduate students) partook in the study. Using the Korean 'word frequency list' developed by Yonsei University and through various sorting processes, the study condensed the original 64,666 emotion words into a finalized 504 words. In the next step, a total of 80 social work students evaluated and classified each word for its meaning and into any of the following categories that seem most appropriate for inclusion: 'happiness', 'sadness', 'fear', 'anger', 'disgust', 'surprise', 'interest', 'boredom', 'pain', 'neutral', and 'other'. Findings showed that, of the 504 feeling words, 426 words expressed a single emotion, whereas 72 words reflected two emotions (i.e., same word indicating two distinct emotions), and 6 words showing three emotions. Of the 426 words that represent a single emotion, 'sadness' was predominant, followed by 'anger' and 'happiness'. Amongst 72 words that showed two emotions were mostly a combination of 'anger' and 'disgust', followed by 'sadness' and 'fear', and 'happiness' and 'interest'. The significance of the study is on the development of a most adaptive list of Korean feeling words that can be meticulously combined with other emotion signals such as facial expression in optimizing emotion recognition research, particularly in the Human-Computer Interface (HCI) area. The identification of feeling words that connote more than one emotion is also noteworthy.

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HRV Evaluation under Stress Condition by Using Patch Type Bipolar Heart Activity Monitoring System (패치형 바이폴라 심장활동 모니터링 시스템을 이용한 스트레스 상태의 HRV 평가)

  • Yang, Heui-Kyung;Lee, Jeong-Whan;Lee, Young-Jae;Kim, Kyeong-Seop;Lee, Kang-Hwi;Choi, Hee-Jung
    • Science of Emotion and Sensibility
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    • v.12 no.2
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    • pp.161-168
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    • 2009
  • In this study, we have developed the patch type HAMS (Heart Activity Monitoring System) which is non-restricted, non-awarable and non-invasive. The module using wireless telecommunication to receive the ECG (electrocardiogram) signal at the computer has mobility which it easily monitors the heart activity of subjects in no time for long term at any time and places. We developed the small patch type electrode which can be attached on the chest. Also the reliability and moving artifact of ECG signal measured by this electrode have been verified. Using HAMS, we measured the HRV (Heart Rate Variability) parameters, the questionnaire evaluation for anxiety and stress and the amount of stress hormone (cotisol) to evaluate the stress effect in HRV on the same subject. As a result of comparing the values under non stressed and stressed condition, there was significant difference on many parameters. And the parameter highly related with stress on Pearson's Correlation Coefficient has been examined. These show that using HAMS is able to evaluate the function of autonomic nervous system. Therefore, we can predict heart problem in daily life by using HAMS. Also we expect that this module can be applied for more application as health monitoring system.

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A Case Study of User-Centered Design Process for Developing Mobile Contents - Focused on Occupation Simulation Game Contents for Children on the Wireless Internet (사용자 중심 디자인 프로세스를 적용한 모바일 컨텐츠 개발 사례 - 어린이를 위한 무선인터넷 기반의 직업 시뮬레이션 게임 컨텐츠 개발을 중심으로)

  • 최수의;김현정
    • Archives of design research
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    • v.17 no.1
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    • pp.309-318
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    • 2004
  • As the mobile market has been expanded and segmented, a mobile market for kids could be possibly appeared sooner or later. Then, it is necessary to develop a new contents for the new media - a mobile game hardware for kids. These days, kids are most interested in computer games, and they do not have enough time to play with peers. Therefore, in this paper, edutainment game contents based on the wireless internet, are developed. The game could supply kids' learning, fun and especially, peer interaction. In order to develop a game contents through user centered design process, the state of art in mobile hardware and contents was examined, a secondary research and interviews and survey was conducted to understand users. Then, when ideas for game contents has suggested, behavior prototype test was done to verify and modify contents. The suggested game contents in this study, is a occupation simulation game, in which kids simulate their own future career and learn related knowledge in a unintentional way. The result of the study suggests the new direction of edutainment game contents and platform. Also, this study shows the representation of user-centered contents developing process for kids, which could be helpful for the following studies.

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The Aspectual Theory of the Cybercharacter (사이버캐릭터의 위상론)

  • 이선교
    • Archives of design research
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    • v.12 no.4
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    • pp.182-190
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    • 1999
  • There has been the rapid change of paradigm with the overflow of terms related to computers such as information, digital, cyber, virtual world and the change of time concept on the ground that it is common to change the world into virtual time. This study is about cybercharacters working in air-broadcasting with rapidly-developing internet, The cybercharacters including 3D animation developed from 2D animation are know to be manufactured with use of electronic mediun and computers and to exist in electronics. Though the emergence of the cybercharacters has a lot of gflnetic roots according to their objectives, they have in common that they are made by 3D graphics and they work in the virtual space, The great traits of the cybercharaters lie in the extension of interfacial function and ecological growth. In the cyberspace the interface, the meeting point between a computer and its users is the most important, The cybercharacters as medium providing new ruman interface become effective with growing interest in virtual reality, The cybercharacters also keep the ecological traits, They can also bring about added value with infusion of image and development of the network, These cybercharacters can also play the important parts in the continually developing cyberspace, The successful birth of the cybercharacter are based on, the technological power. assistance of fund and the ctrltural background, The information-entertainment of the cybercharacters functions well with the accompinimene of these three things, The cybercharacters can make a subject which keeps single issue as a central point of the virtual realty, The cybercharacters can also be connected with equity of "Korean knowledge information society" in the cultural rule of the internet and sociocul tural identity, identity.

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A Study on Establishing Online Document Communication System by Means of Intranet Web Site (ODCS(Online Document Communication System)인트라넷 웹사이트 구축과정 및 사용자 효과 연구)

  • 양초산
    • Archives of design research
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    • v.17 no.3
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    • pp.167-178
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    • 2004
  • The purpose of this treatise is to show merits and method of establishing Lotte department store design division Online Documents Communication System through illustration of examples of intranet in which internet environment convenient to use for its openness is applied for establishing Design Online Documents Communication System for fundamentals of organization. In this connection merits and effect attainable from establishing Design Outline Documents Communication System of the enterprise as found were as follows: Firstly, it brought about reduction in workload of staffs through sharing various existing resources. It reduced redundant works and enables speedy handling of works. Secondly, it was possible to exchange viewpoints and share information by pertinent parties. Thirdly, by expediting information exchange and communication among persons in charge it was possible to improve work efficiency. Fourthly, it was possible to build and operate such system at relatively low cost on the basis of web browser. Without using any other significant instrument or equipment but by linking it to business network and using existing computer system operation was possible. Fifthly, by common sharing of work exclusive to design room through on-line it was possible to improve professionalism and convenience in data preservation. Through this treatise and survey and study on process for establishing intranet it was possible to find that there were sharing work, improving work efficiency, reducing workload, saving cost and expediting communication to a significant degree.

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