• 한국정보통신학회논문지
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• 제18권11호
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• pp.2640-2644
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• 2014

최근의 기술발전과 함께 무선 센서 네트워크 (Wireless Sensor Network, WSN)는 수많은 작고 저렴한 센서 노드로 구성된 센서네트워크이다. 무선 센서 네트워크는 공동으로 배치된 지역 내에서 정보감지, 수집, 처리 및 전송임무를 수행한다. 또한, 지능형교통, 의료구조, 환경감시, 정밀농업 및 공업 자동화 등 다양한 방면에 응용할 수 있다. 그래서 센서 네트워크 환경에서 데이터 유지관리 기술은 센서 네트워크의 핵심 기술 중 하나이다. 본 논문은 현재 무선 센서 네트워크 데이터 관리를 위한 기술을 분석하고 이들의 문제점에 대해 살펴보았다. 향후 본 연구를 통해 센서 네트워크의 체계적인 개발 접근을 시도해볼 수 있을 것이다.

• 한국통신학회논문지
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• 제37C권10호
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• pp.901-908
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• 2012

미래의 지능형 공장 환경은 관리자가 M2M (Machine-to-Machine) 통신을 이용하여 원격으로 공장 안의 기기들의 동작 상태와 환경을 인지하고 관리하는 것을 목표로 하고 있다. 하지만, 공장 안에서 사용하는 통신 프로토콜인 WLAN (Wireless Local Area Network), ZigBee, Bluetooth 등은 동일한 ISM (Industrial Scientific Medical) 대역을 사용하기 때문에 상호 간섭이 발생하게 된다. 본 논문에서는 Fingerprinting 무선측위 기술을 이용하여 영역 기반으로 주파수를 할당하는 기법을 제안한다. 그리고 일반적인 기법이 가지고 있는 측위 성능의 문제점을 개선하기 위하여, k-NN (Nearest Neighbor) 알고리즘을 적용하고 또한 이를 기반으로 한 새로운 기법도 제안한다. 모의실험 결과를 통해 제안된 무선측위 알고리즘이 다른 기법들보다 측위 성능의 오차가 감소하였으며, 궁극적인 목표로 하고 있는 채널 간섭율 또한 향상되었기에 주파수의 간섭을 보다 효율적으로 관리할 수 있다는 결론을 얻었다. 아울러 지속적인 위치 추정을 통하여 공장 환경 내 안전도 보장할 수 있음을 확인하였다.

• 한국안전학회지
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• 제23권6호
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• pp.14-20
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• 2008

A large number of accidents have been occurred in the domestic shipbuilding industry. Its number of accidents is approximately twice than that of manufacturing industry and three times larger than that of whole industry in general. There are several reasons that make it hard to control the accidents. First, it is because the shipbuilding industry is composed of many subcontractors who may need improvement in safety education and safety management. Second, the shipyard environments are exposed to lots of hazards such as high elevation works, isolated workspaces, heavyweight and huge structures/components. Last, the shipbuilding industry has grown too rapidly in a short period. For that reason, the safety management standards and safety consciousness could not catch up the speed of its development. In this study, it is suggested to use a more efficient and easier way to conduct safety management using a web-based safety management system for the shipbuilding industry. This system is composed of four main parts, which is available for self-auditing with legal support. Those are checklists based safety and health evaluation, safety inspection, user shared accident database and user shared bulletin board. It is expected that this system can help us to reduce risks in the shipbuilding industry considerably.

• 식품과학과 산업
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• 제45권4호
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• pp.16-20
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• 2012

Although the technology of breadmaking simply goes through the process of mixing, fermentation, and baking, it is very hard to make a same product every day. The reason is that baking science begins with the very first process of breadmaking which is mixing, and every steps and working environments are so closely connected. The baking science has developed in short time since the theory of fermentation has released. If you check the development of baking technology synthetically, it is consisted of the discovery of nutritional and functional ingredients, the optimization process of new machines, and the maintenance of the quality as fulfilling social demands. Because the baking business is making and selling the product, baking itself is a business, and it has the form that manufacturing and service business coexist. In today's current domestic bakery market, the supply exceeds the demand. Moreover, the concept of bakery itself has been changing from the fixed image of bakery which is selling the bread to the differentiated bakery with others. As we look at the general bakery's trends, it is focused on going back to the basic or traditions, going to the functional, and working with automations. To conclude, the baking has a long history, but it actually has the short history in the technological development. Baking business can be viewed as the simple business, but many factors are related to the business. It has a few basic kinds of products in baking, but it has diverse kinds of products with the base of infinite creativity. Even though it is physically a hard working business, it is also a business that can face with fun. For managing a bakery, finally, the differentiated strategy with other bakery that maximizes the customers' value is needed.

• Journal of the Optical Society of Korea
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• 제12권4호
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• pp.262-268
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• 2008

A compact imaging spectrometer (COMIS) for use in the STSAT3 microsatellite is currently under development. It is scheduled to be launched into a low Sun-synchronous Earth orbit (${\sim}700km$) by the end of 2010. COMIS was inspired by the success of CHRIS, which is a small hyperspectral imager developed for the ESA microsatellite PROBA. COMIS is designed to achieve nearly equivalent imaging capabilities of CHRIS in a smaller (65 mm diameter and 4.3 kg mass) and mechanically superior (in terms of alignment and robustness) package. Its main operational goal will be the imaging of Earth's surface and atmosphere with ground sampling distances of ${\sim}30m$ at the $18{\sim}62$ spectral bands ($4.0{\sim}1.05{\mu}m$). This imaging will be used for environmental monitoring, such as the in-land water quality monitoring of Paldang Lake, which is located next to Seoul, South Korea. The optics of COMIS consists of two parts: imaging telescope and dispersing relay optics. The imaging telescope, which operates at an f-ratio of 4.6, forms an image (of Earth's surface or atmosphere) onto an intermediate image plane. The dispersion relay optics disperses the image and relay it onto a CCD plane. All COMIS lenses and mirrors are spherical and are made from used silica exclusively. In addition, the optics is designed such that the optical axis of the dispersed image is parallel to the optical axis of the telescope. Previous efforts focused on manufacturing ease, alignment, assembly, testing, and improved robustness in space environments.

• Advances in aircraft and spacecraft science
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• 제4권2호
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• pp.145-167
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• 2017

The presented paper gives an overview of several projects addressing the experimental characterization and control of the buffet phenomenon on 3D turbulent wings in transonic flow conditions. This aerodynamic instability induces strong wall pressure fluctuations and therefore limits flight domain. Consequently, to enlarge the latter but also to provide more flexibility during the design phase, it is interesting to try to delay the buffet onset. This paper summarizes the main investigations leading to the achievement of open and closed-loop buffet control and its experimental demonstration. Several wind tunnel tests campaigns, performed on a 3D half wing/fuselage body, enabled to characterize the buffet aerodynamic instability and to study the efficiency of innovative fluidic control devices designed and manufactured by ONERA. The analysis of the open-loop databases demonstrated the effects on the usual buffet characteristics, especially on the shock location and the separation areas on the wing suction side. Using these results, a closed-loop control methodology based on a quasi-steady approach was defined and several architectures were tested for various parameters such as the input signal, the objective function, the tuning of the feedback gain. All closed-loop methods were implemented on a dSPACE device able to estimate in real time the fluidic actuators command calculated mainly from the unsteady pressure sensors data. The efficiency of delaying the buffet onset or limiting its effects was demonstrated using the quasi-steady closed-loop approach and tested in both research and industrial wind tunnel environments.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2019년도 춘계학술대회
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• pp.576-578
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• 2019

가상현실은 체험하기 어려운 환경을 실제처럼 체험할 수 있도록 해주는 기술로써 최근 게임, 의료, 국방, 제조업 등 여러 분야에 활용되고 있다. 본 연구에서는 가상현실 기술을 활용하여 여행할 행선지를 미리 맛보고 여행 장소를 고를 수 있는 콘텐츠 개발을 제안한다. 일반적으로 여행지를 정할 때 웹 사이트나 책자를 활용하여 여행지에 대한 정보를 찾아본다. 최근에는 여행지를 추천해 주는 어플리케이션도 개발되어 활용되고 있다. 그러나 여행지에 대한 정보를 가상현실로 구현하여 보여 주면 보다 확실하고 실감나는 정보를 얻을 수 있을 것이다. 구글 맵 VR과 같이 전체적으로 지구를 보여주고 확대하거나 축소를 할 수 있고 키워드를 클릭하면 그 키워드에 맞는 관광지를 추천을 해 준다. 인테넷 브라우징 쿠키를 이용해서 이용자의 관심을 따라서 자동으로 관광지를 보여준다.

• 한국정보통신학회논문지
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• 제24권7호
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• pp.873-878
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• 2020

최근 3D 프린터의 발전으로 인하여 3D 프린팅에 대한 관심이 커지고 있다. 3D 프린팅은 사용자의 요구특성에 맞도록 제품을 설계하여 개인의 욕구와 다양한 요건들이 반영되어야 한다. 3D 프린팅 제품이 사용자의 요구특성에 따른 제품 구매 의도에 관한 활용방안 연구는 미흡하다. 따라서 본 연구는 3D 프린팅 환경에서 개인 맞춤형 컨트롤러 제품 구매 의도의 영향요인에 대하여 알아보기 위하여 설문조사 및 통계분석 하였다. 연구결과 사용자의 혁신성과 편의성 안전성이 개인 맞춤형 컨트롤러 제품의 만족과 구매 의도에 중요한 요소임을 확인하였다. 3D 프린팅을 활용한 컨트롤러 제품 제작 시 사용자의 혁신성과 편의성, 안전성을 고려한다면 개인 맞춤형 컨트롤러제작의 가치를 높일 수 있을 것으로 예상된다. 개인 맞춤형 제품의 생산방식을 초기에 성공적으로 도입하고 이를 구체적이고 체계적으로 지원하는 개인 맞춤형 제품 개발 프레임워크에 관한 연구가 필요하다.

• 한국안전학회지
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• 제36권1호
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• pp.36-43
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• 2021

Effective leadership in safety performance, such as safety leadership, has received attention as a factor that greatly affects safety performance in various high-risk industrial environments. Based on prior research, this study aims to analyze the impact relationship between safety leadership, safety observance, safety education, and safety culture to reveal the effectiveness of safety leadership. In addition, this study will examine the effects of safety leadership on safety observance and safety education to identify the effects of safety understanding. For this purpose, a survey was conducted with employees of an aviation manufacturing company in Gyeongnam. For verification, a positive factor analysis, correlation analysis, and structural equation analysis were conducted using the AMOS 21.0 program. This study's findings show that, first, safety leadership has a positive and significant impact on safety observance and safety education. Second, safety leadership was found to have a direct impact on organizations' safety culture. Third, although safety observance has significant positive effects on safety culture, safety education has often been rejected. Finally, after verifying the control effect of safety understanding, this study uncovered the presence of an adjustment effect in the effect of safety leadership on safety observance. Therefore, based on the results of this study, theoretical and practical implications suggest that through the exercise of safety leadership, managers can improve their organizations' safety culture by increasing organizations' compliance with safety observance and/or acceptance of safety education.

• 항공우주시스템공학회지
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• 제16권3호
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• pp.35-41
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• 2022

UAM(Urban Air Mobility) 은 승객과 화물을 운반할 수 있는 새로운 형태의 안전하고 적합한 운송수단으로써 각광받고 있다. UAM 의 상업적인 사용은 2025년부터 시작될 것으로 예측되고 있다. UAM의 생산률은 기존 항공기 생산률보다 자동차 생산률에 더 가까울 것으로 예측되므로, 대량 생산 항공기에 대비한 새로운 인증 방안을 구축할 필요가 있다. 이러한 UAM은 구조물의 중량을 줄이기 위해 복합재료가 주 재료로써 사용될 것으로 예상되고 있다. 따라서 본 연구에서는 항공기용 복합재료 시범인증을 수행함으로써 국내 복합재료 인증 방안을 제시하고 인증소재를 소형 항공기용 부품에 적용하기 위한 연구를 수행하였다. 본 연구를 통해 대량생산이 필요한 UAM 항공기의 인증 시간을 절감할 수 있을 것으로 예상한다.