• Smart Structures and Systems
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• 제6권2호
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• pp.135-146
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• 2010

This paper presents the perspective of the Structural Mechanics program of the Air Force Office of Scientific Research (AFOSR) on the damage assessment of structures for the period 2006-2009 when the author was serving as Program Manager at AFOSR. It is found that damage assessment of structures plays a very important role in assuring the safety and operational readiness of US Air Force fleet. The current fleet has many aging aircraft, which poses a considerable challenge for the operators and maintainers. The nondestructive evaluation technology is rather mature and able to detect damage with considerable reliability during the periodic maintenance inspections. The emerging structural health monitoring methodology has great potential, because it will use on-board damage detection sensors and systems, will be able to offer on-demand structural health bulletins. Considerable fundamental and applied research is still needed to enable the development, implementation, and dissemination of structural health monitoring technology.

• Structural Engineering and Mechanics
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• 제35권2호
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• pp.127-140
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• 2010

This paper focuses on a number of criteria that enable controlling the influence of geometric simplification on the quality of finite element (FE) computations. To perform the mechanical simulation of a component, the corresponding geometric model typically needs to be simplified in accordance with hypotheses adopted regarding the component's mechanical behaviour. The method presented herein serves to compute an a posteriori indicator for the purpose of estimating the significance of each feature removal. This method can be used as part of an adaptive process of geometric simplification. If a shape detail removed during the shape simplification process proves to be influential on mechanical behaviour, the particular detail can then be reinserted into the simplified model, thus making it possible to readapt the initial simulation model. The fields of application for such a method are: static problems involving linear elastic behaviour, and linear thermal problems with stationary conduction.

• 정보관리학회지
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• 제22권3호
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• pp.13-36
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• 2005

지식기반사회에서 문화정보의 중요성이 부각되면서 전반적인 국가경제 패러다임의 변환이 요구되고 있다. 본 연구에서는 문화정보의 중요성과 국가 문화정보망의 필요성에 대하여 정책적 분석과 현황적 분석, 그리고 경제적 분석을 통한 당위성을 제시하고자 한다. 이러한 당위성에 근거하여 새로운 국가 문화정보망의 현황과 구체적인 구축 방향을 제시함으로써 국가 차원의 문화정보의 육성정책을 강조하고자 한다.

• 한국분말재료학회지
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• 제22권5호
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• pp.337-343
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• 2015

Powder compaction is a continually and rapidly evolving technology where it is a highly developed method of manufacturing reliable components. To understand existing mechanisms for compaction, parameter investigation is required. Experimental investigations on powder compaction process, followed by numerical modeling of compaction are presented in this paper. The experimental work explores compression characteristics of soft and hard ductile powder materials. In order to account for deformation, fracture and movement of the particles, a discrete-finite element analysis model is defined to reflect the experimental data and to enable investigations on mechanisms present at the particle level. Effects of important simulation factors and process parameters, such as particle count, time step, particle discretization, and particle size on the powder compaction procedure have been explored.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.648-655
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• 1993

The hydraulic coconut dehusking machine consists of three main parts ie. The frame , the power unit including the hydraulic accessories, the lifting and dehusking mechanisms. Two sets of the hydraulic coconut dehusking machine were developed . their hydraulic and electrical control circuits were connected in series to enable them operating contemporaneously. Two operators are required to operate the machine. Each of them put a coconut on the lifting mechanism in order to start the working cycle automatically. As a result, the nut are immediately pushed up and seized by the holding teeth under the supplement of the hydraulic reducing circuit. After that the dehusking mechanism started operating via the sequence circuit. At the end of the cycle, both mechanisms return to their original positions. Some remaining fibrous is taken out manually from the nut subsequently . The continuous dehusking speed was found to be 22.2 seconds per 2 coconuts.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2003년도 추계종합학술대회 논문집
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• pp.113-119
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• 2003

컴퓨팅 환경의 고도화와 인터넷 사용자의 급증으로 인해 현재의 Web기반 클러스터 시스템 어카운팅 서비스는 과거에 비해 다수의 사용자로 하여금 보다 많은 양의 데이터를 고속으로 접근할 수 있게 하고있다. 하지만 시스템 환경의 편리함 만큼이나 사용자정보와 데이터의 보안 역시 중요한 요소 중 하나이며 특히 데이터 유출, 해킹 그리고 악의적인 코드 등으로 인한 개인과 기관의 피해는 인터넷 서비스 사업 분야에 있어 매우 중요한 문제로 대두되고 있다. 본 연구에서는 국내 TTA(한국정보통신기술협회) 표준 암호 알고리즘인 SEED를 이용한 보다 안정적인 웹기반 클러스터시스템 어카운팅 서비스 방안을 제안한다.

• 한국콘텐츠학회논문지
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• 제15권8호
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• pp.1-8
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• 2015

아두이노는 오픈소스 기반 프로토타이핑 플랫폼으로, 미디어아트, 시뮬레이션, 인터랙션 장치 등 다양한 분야에서 활용되고 있다. 아두이노 어플리케이션은 C언어를 기반으로 개발되기 때문에 프로그램의 효과적인 설계명세 양식을 제공하지 못한다. 본 논문에서는 표준 객체지향 모델링 언어인 UML의 확장 매커니즘을 이용한 아두이노 어플리케이션 설계방법을 제안한다. 제안한 방법을 통해 아두이노 어플리케이션의 주 기능인 디지털 입출력, 아날로그 입출력 등을 UML 표기법을 이용하여 명세할 수 있다.

• 대한의용생체공학회:의공학회지
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• 제15권1호
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• pp.105-110
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• 1994

In this paper, we present a method to evaluate source locations and distributed region which is specified brain activity, as indicated by locations and strengths of intracranial sources, using potential gradients of interpolation polynomials and topographic mapping of the EEG records. This method can analyze the variance of source temporally or spatially and leads to enable a quantitative evaluation of potential gradients drawing methods which is now being used in the clinic. In the result, we obtained the overall potentials distribution on the entire scalp and the information of potential source locations from the EEG records of a patient which was known to epilepsy.

• 대한의용생체공학회:의공학회지
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• 제7권2호
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• pp.169-182
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• 1986

Pulsed ultrasonic Doppler system is a useful diagnostic instrument to measure blood-flow-velocity, velocity profile, and volume-blood-flow. This system is more powerful compare with 2-dimensional B-scan tissue image. A system has been deve- loped and ii being evaluated using TMS 32010 DSP. We use this DSP for the purpose of real-time spectrum analyzer to obtain spectrogram in singlegate pulsed Doppler system and for the serial comb filter to cancel clutter and zero crossing counter to estimate Doppler mean frequency in multigate pulsed Doppler system. The Doppler shift of the backscattered signals is sensed in a phase detector. This Doppler signal corresponds to the mean velocity over a some region in space defined by the ultrasonic beam dimensions, transmitted pulse duration, and transducer ban(iwidth. Multi- gate pulsed Doppler system enable the transcutaneous and simultaneous assessment of the velocities in a number of adjacent sample volumes as a continuous function of time. A multigate pulsed Doppler system processing the information originating from presented.

• 한국멀티미디어학회논문지
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• 제16권6호
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• pp.735-745
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• 2013

The emergence of Web 2.0 technologies, such as blogs and wiki, enable even naive users to easily create and share content on the Web using freely available content sharing tools. Wide availability of almost free data and promiscuous sharing of content through social networking platforms created a content borrowing phenomenon, where the same content appears (in many cases in the form of extensive quotations) in different outlets. An immediate side effect of this phenomenon is that identifying which content is re-used by whom is becoming a critical tool in social network analysis, including expert identification and analysis of information flow. Internet-scale reuse detection, however, poses extremely challenging scalability issues: considering the large size of user created data on the web, it is essential that the techniques developed for content-reuse detection should be fast and scalable. Thus, in this paper, we propose a $qSign_{lsh}$ algorithm, a mechanism for identifying multi-sentence content reuse among documents by efficiently combining sentence-level evidences. The experiment results show that $qSign_{lsh}$ significantly improves the reuse detection speed and provides high recall.