• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2006년도 한국컴퓨터종합학술대회 논문집 Vol.33 No.1 (C)
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• pp.61-63
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• 2006

휴대용 기기들의 데이터 저장소로 플래시 메모리가 많이 사용되고 있으며 플래시 메모리가 대용량화 되어감에 따라 점차 디스크를 대체할 것이라 예상된다. 따라서 데이터베이스 시스템 역시 저장 매체로 플래시 메모리의 사용이 증가할 것으로 예상되며 이에 따른 효율적인 인덱스가 필요하다. 플래시 메모리 기반의 효율적인 인덱스 구축을 위하여 B+ 트리의 페이지 크기에 따른 성능 평가가 필요하다. 본 논문에서는 B+ 트리와 버퍼 관리자를 구현하고, 플래시 변환 계층의 대표적인 4 가지 알고리즘에 대해 B+ 트리의 페이지 크기에 따른 성능을 비교, 분석하여 플래시 메모리 기반의 인덱스를 구축하기 위한 방향을 제시한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.110-113
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• 2004

Underwater acoustic(UWA) communication is one of the most difficult field because of several factors such as multipath propagation, high temporal and spatial variability of channel conditions. Therefore, it is important to model and analyze the characteristics of underwater acoustic channel such as multipath propagation, transmission loss, reverberation, and ambient noise. In this paper, UWA communication channel is modeled with a ray tracing method and applied to image transmission. Quadrature phase shift keying(QPSK) and multichannel decision feedback equalizer(DFE) are utilized as phase-coherent modulation method and equalization technique, respectively. The objective is to improve the performance of vertical sensor array than that of single sensor in the viewpoint of bit error rate(BER), constellation output, and received image quality.

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2003년도 가을학술발표대회
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• pp.128-129
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• 2003

• 스마트미디어저널
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• 제4권2호
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• pp.46-54
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• 2015

Communication between ECUs (Electronic Control Units) in agricultural machineries tends to use IS011783 widely, that is PGN (Parameter Group Number) based communication protocol lays on CAN protocol by altering its identifier part. Messages in line are transferred and received between ECUs according to ISO11783 standard. This paper discusses about design of wireless monitoring system. We used an ARM Cortex-M3 microcontroller embedded development board and marvel8686 wireless module. The wireless ISOBUS monitoring system, attached to communication line, reads messages, interpret them, and display them on the screen in easily comprehendible form. It can be used to generate messages and monitor the traffic on physical bus systems. The monitoring system connected to ECUs, monitor and simulate real traffic of communication and functionality of the ECUs. In order to support our work, we have implemented the monitoring tool. The development consists of two parts: GUI of the application and firmware level programming. Hence the monitoring system is attached to the communication line and equipped by Wi-Fi module; farmer/dispatcher in a farm monitors all messages in communication line on personal computer and smart device.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제15권1호
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• pp.1-11
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• 2015

A concept of Deep Level Situation Understanding is proposed to realize human-like natural communication (called casual communication) among multi-agent (e.g., humans and robots/machines), where the deep level situation understanding consists of surface level understanding (such as gesture/posture understanding, facial expression understanding, speech/voice understanding), emotion understanding, intention understanding, and atmosphere understanding by applying customized knowledge of each agent and by taking considerations of thoughtfulness. The proposal aims to reduce burden of humans in humans-robots interaction, so as to realize harmonious communication by excluding unnecessary troubles or misunderstandings among agents, and finally helps to create a peaceful, happy, and prosperous humans-robots society. A simulated experiment is carried out to validate the deep level situation understanding system on a scenario where meeting-room reservation is done between a human employee and a secretary-robot. The proposed deep level situation understanding system aims to be applied in service robot systems for smoothing the communication and avoiding misunderstanding among agents.

• 한국비블리아학회지
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• 제2권1호
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• pp.66-87
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• 1974

It is the prime importance of the information and the reference-librarians to better understand the communication functions of the library since they are the ones to whom the library users come first with their informational needs. Reference librarians often have the problem of providing information to those who may have little experience with, or interest in the library. There is also a problem of finding out what the person really wants, not what he says he wants. Therefore, the interaction between the librarian and the user involves a highly complex activity of communication with each other even before the actual search begins. Reference librarians cannot perform to any degree of success without comprehension of the general patterns and processes of communication in information seeking. Nonverbal as well as verbal transmittal process on the part of both librarians and patrons should not be overlooked. Some of the difficulties and barriers of library communication are brought so that possible cures and improvement may be sought. The basic purpose of the reference interview through which this interpersonal communication takes place is for the reference specialist to enable to link the needs of the patron with potential resource of the library. The writer firmly believes that this importance of the process be taught as well as the materials in reference service regardless of the level of the course offered in library science department.

• BMB Reports
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• 제44권1호
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• pp.1-10
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• 2011

Inter-cellular communication via diffusible small molecules is a defining character not only of multicellular forms of life but also of single-celled organisms. A large number of bacterial genes are regulated by the change of chemical milieu mediated by the local population density of its own species or others. The cell density-dependent "autoinducer" molecules regulate the expression of those genes involved in genetic competence, biofilm formation and persistence, virulence, sporulation, bioluminescence, antibiotic production, and many others. Recent innovations in recombinant DNA technology and micro-/nano-fluidics systems render the genetic circuitry responsible for cell-to-cell communication feasible to and malleable via synthetic biological approaches. Here we review the current understanding of the molecular biology of bacterial intercellular communication and the novel experimental protocols and platforms used to investigate this phenomenon. A particular emphasis is given to the genetic regulatory circuits that provide the standard building blocks which constitute the syntax of the biochemical communication network. Thus, this review gives focus to the engineering principles necessary for rewiring bacterial chemo-communication for various applications, ranging from population-level gene expression control to the study of host-pathogen interactions.

• 한국초등과학교육학회지:초등과학교육
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• 제38권1호
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• pp.16-30
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• 2019

This study aimed to develop and apply the process-focused assessment, and verify the assessment's effectiveness for improving scientific communication skills in elementary science learning. To achieve the aims of this study, the unit "Action of Electricity" in elementary science text book for 5-6th students was selected, and then 13 process-focused assessments were developed to improve scientific communication skills. 119 elementary school students in 6th grade participated in this research. it was performed to compare between 60 students on the general assessment and 59 students on the process-focused assessment in the results of achievement levels on scientific concept and scientific communication skills. The results were as follows: First, this study showed that process-focused assessment had higher educational effectiveness in specific area of scientific communication skills than the general assessment. Second, the process-focused assessment can help to form students' scientific concepts as the general assessment. Furthermore, the process-focused assessment group was more effective at reducing the non-scientific concept than the general assessment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권1호
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• pp.277-290
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• 2019

The demand for indoor positioning is increasing day by day. However, the widely used positioning methods today cannot satisfy the requirements of the indoor environment in terms of the positioning accuracy and deployment cost. In the existing research domain, the localization algorithm based on three-dimensional space is less accurate, and its robustness is not high. Visible light communication technology (VLC) combines lighting and positioning to reduce the cost of equipment deployment and improve the positioning accuracy. Further, it has become a popular research topic for telecommunication and positioning in the indoor environment. This paper proposes a surface centroid TOA localization algorithm based on the VLC system. The algorithm uses the multiple solutions estimated by the trilateration method to form the intersecting planes of the spheres. Then, it centers the centroid of the surface area as the position of the unknown node. Simulation results show that compared with the traditional TOA positioning algorithm, the average positioning error of the surface centroid TOA algorithm is reduced by 0.3243 cm and the positioning accuracy is improved by 45%. Therefore, the proposed algorithm has better positioning accuracy than the traditional TOA positioning algorithm, and has certain application value.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (A)
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• pp.826-828
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• 2005

이동 기기의 저장 장치로 플래시 메모리가 널리 사용되고 있으며 고정 하드 디스크를 대체하는 저장 매제로 부상하고 있다. 그러므로 플래시 메모리의 특성을 잘 이해하고, 최대한 효율적으로 플래시 메모리를 사용할 필요성이 있다. 이러한 역할을 해주는 것은 플래시 내부의 시스템 소프트웨어인 FTL(Fiash Translation Layer)이다. FTL은 운영체제가 디스크에 전달하는 블록을 물리적인 플래시 메모리에 맵핑하는 역할을 한다. 그러므로 플래시 메모리의 성능은 FTL 알고리즘이 결정한다. 플래시를 대체한 플래시 디스크에서는 기존의 파일 시스템이 탑재되며 간단한 섹터 기반외 이동형 기기에서와는 다른 특성을 가진다. FTL 성능을 평가하기 위해서는 실제적으로 플래시 메모리가 장착된 제품들이 동작하는 시스템에서 실험을 해야 한다. 많은 플래시 디스크는 윈도우즈에서 동작하므로 윈도우즈의 디스크 I/O를 추출하여 실험을 해야만 한다. 본 논문에서는 윈도우즈에서 물리적인 디스크 I/O 패턴을 추출하여 FTL 알고리즘의 성능을 평가하기 위한 도구 개발에 대하여 설명하고 이에 대한 간단한 결과를 보인다.