• 대한기계학회논문집B
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• 제30권9호
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• pp.898-904
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• 2006

A new method measuring thermal conductivity of fluids is proposed in this research. It is based on the steady state heat transfer from a hot central cylinder to a cold outer cylinder located concentrically. This method guarantees more stable measurement than conventional THM(transient hot-wire method) due to its simplicity of theoretical principle. Measurements was made for the three nanofluid samples with different particle concentration of pure, 2% and 4%. Nanofluids are made by mixing the pure transformer oil with AlN nano particles. Design of the sensor module and experimental procedures are explained and comparison of the measuring data between present method and THM was made in detail.

• Design & Manufacturing
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• 제13권1호
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• pp.19-24
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• 2019

Currently, the world is paying keen attention to the production of renewable energy along with environmental issues, and the share of renewable energy in the world is rising above that of nuclear power. Especially when Korea, which is heavily dependent on foreign countries, needs to reconsider its national competitiveness due to the recent high oil prices, the government's energy policy is to develop and use renewable energy that replaces fossil fuels. In particular, solar energy, the most actively studied and commercialized field of renewable energy, is the main research for solar energy and is commercialized and used. However, the efficiency of solar energy has already reached saturation. Studies are also focusing on increasing the reflectivity of solar energy to increase efficiency. Therefore, this paper proposes a solar collection system that can utilize solar energy rather than solar energy. The proposed solar heat collection system uses solar tracking systems to effectively collect solar energy, particularly those that can be easily produced using single-modular reflectors and have price competitiveness. In addition, temperature measurement experiments with temperature measuring sensors were conducted to ensure reliability in order to verify the results interpreted.

• 전자공학회논문지CI
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• 제48권1호
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• pp.65-71
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• 2011

현대 사회에서 자동차는 가장 중요한 이동수단으로써 사용되고 있다. 그로 인해 교통사고 또한 증가되고 있는 추세이다. 교통사고의 가장 큰 요소는 운전자이다. 그렇기 때문에 운전자에 대한 연구는 반응속도, 심리상태, 생체 선호, 연령, 주행패턴 등으로 다양하게 진행되고 있다. 본 논문에서는 운전자의 숙련도에 따른 장애물 인식 반응속도를 측정하기 위한 임베디드 시스템을 설계하였다. 본 논문에서 제안된 시스템은 브레이크 측정 모듈과 OBD-2 스캐너, 블루투스 전송 모듈로 구성되어있다. 또한, 측정된 데이터를 저장하고 분석하기 위해 GUI 프로그램과 데이터베이스를 구축하였다. 제안된 시스템을 통해 운전자의 반응 속도를 측정한 결과, 운전 숙련도를 판단할 수 있었다.

• 한국IT서비스학회지
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• 제10권1호
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• pp.65-72
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• 2011

In this paper, we consist of three dimensional acceleration sensor as a small-sized sensor module to acquire base technologies that need to estimate exhibition audience' moving distance. and that we developed algorism and device that can calculate acceleration in gravity direction with attaching it to people's body part without regard to three dimensional direction. By making use of the sensor module, we have to process the data that let it quantitatively process possible to measure people's walk and movement by computer system. We normalized sensor output data in the process of change from sensor module to acquisition of data, rectangular coordinates and single scalar acceleration value in gravity direction. Printed out sensor data attaching sensor module to people's body part is used for motion pattern detection after normalization, Motion sensor devised mode change algorism because it print data of other pattern according to attached position of body. For algorism design, we collected data occurring during walking about subject and we also defined occurring problem domain after analyzing the data. We settle defined problem domain and that we simulated the walking number measuring instrument with highly efficient in restricted environment.

• 한국정보전자통신기술학회논문지
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• 제6권1호
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• pp.51-56
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• 2013

본 논문에서는 LED 조명을 기반으로 미디어 전송기법 가시광통신 시스템 모듈 설계 및 효율 연구와 성능분석을 하였다. 고휘도 Withe LED조명을 이용한 가시광통신(Visible Light Communication) 송 수신기 모듈을 통해 미디어 전송 시스템을 구현하기 위해 송신부에는 1~12개의 LED 발광 소자와 수신부에는 PD(Photo Diode)센서를 구성하여 전송속도에 따른 최대 송 수신의 통신 거리를 실험해 보고자 가시광통신 시스템을 제안하였다. 또한 미디어 전송 시스템의 효율을 증대시키기 위해 LED모듈에 렌즈 착용시와 미착용시 각각의 성능을 측정하여 약 20%의 효율이 증가하였음을 확인 할 수 있었다.

• 한국자동차공학회논문집
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• 제15권4호
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• pp.83-93
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• 2007

This paper represents the development of 3-axises loadcell for measuring the side-force of suspension module of MPV(Multi Purposed Vehicle). The side force causes the failure of damper, such as leakage. The loadcell was developed using strain gauges, and the Wheastone bridge circuit to compensate for the cross-talk between the each axises and the measurement error by temperature. Structure analysis of loadcell was accomplished with FEM(Finite Element Method) to optimize the location of strain gages. The design optimization for important factors that have an effect on performance of loadcell was accomplished by using DOE(Design of Experiment). Loadcell was produced and successfully tested, showing good sensitivity and low cross-talk. The cross-talk of the developed loadcell is bellow 5%. The load history was measured at proving ground. The maximum side-force, the longitudinal force, and vertical force of MPV are 4.2 kN, 8.0 kN, and 17.0 kN, respectively, at Belgian road.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.765-768
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• 2008

To make 3D camera system, we check the possibility of advanced range camera module based on measuring the time delay of modulated infrared light, using a single detector chip fabricated on standard CMOS process. To depth information, electronic shutter and interlaced scanning method of 2D sensor is needed. Especially, we design "lens system, illumination unit" and review simulation result.

• Journal of Positioning, Navigation, and Timing
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• 제2권1호
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• pp.67-74
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• 2013

In this study, a remote controller was designed using localization technique. The designed remote controller system consists of infrared transmit/receive module for time synchronization, ultrasonic transmit/receive module for measuring the TOA value, and micro-controller for processing the measured data value. For the position estimation method of remote controller, the Savarese method was used which does not have a problem of diverging solution depending on initial value. The noise included in the measured value was removed by separating the signal and noise with the use of EMD method which is the non-stationary signal analysis technique. The designed system was tested by constructing a simulation environment, and the improvement of accuracy and precision for the application of EMD method was examined.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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• pp.36-36
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• 2002

To Establish of standard technique of length measurent in 2D plane, we develope AFM system. The XY scanner scans the sample only in XY plane, while the Z scanner scans the specimen only in Z-direction. Cantilever tip is controlled to has constant height relative to speciman surface by feedback of PSPD signal. To acquire high accuracy, Z-axis measuring sensor will be added.(COXI or others). In this paper we design XYZ stage suitable for this AEM system. For XY stage, single module parallel-kinnematic flexure stage is used which has high orthogonality and minimum out-of-plane motion. To obtain best performance optimal design is performed. For XY stage, to be robust about parasitic motion optimal design of maximizing Z and tilt stiffness is performed under the constraint of motion range and stage size. And for Z stage, optimal design of maximizing 1st resonant frequency is performed. Because if resonant frequency is get higher, scan speed is improved. So it makes reduce the error by sensor drift. Resultly XYZ stage each have 1st natural frequency of 115㎐, 201㎐, 2.66㎑ and range 109㎛, 110㎛, 12㎛.

• 조형예술학연구
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• 제2권
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• pp.42-89
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• 2000

Industrial ceramic of Korean industrial design, especially tableware show different characteristics in their forms between 1940s-1960s, and 1970s-1990s. The shift of such changes can be verified objectively by module measurement. The validity of the results applying this method is supported by the investigation of the change of aesthetic modes in Korean society. The most obvious change in the figurative characteristics of tableware is in the outline of their external shapes. 'Module' is used to describe and analyze the changes of such an external shape more strictly as the objective method and measuring the module is employed. This method was developed by the combination of the method analyzing figurative art works by Re Corbuise who uses 'module' with Hambidge's method to describe and analyze the works by means of the golden section. The shift of flgurative changes of tableware could be examined objectively and elaborately by such a newly developed method. The industrialization of tableware production in Korea was begun in 1940s. Then its design was not activated, but as the society has been stabilized through the liberation and civil war, design was settled in 1960s. After that, the design has played the essential roles in 1970s. And as the importance of design in producing goods has been recognized according to the economic growth. The design of tableware shows a remarkable difference based on 1960s and 1970s in such an economic growth. It is resulted from the scientific data analysis of the design since 1940 without any preference. According to the results which analyze the external shapes of tableware for last 50 years, the tableware designs show much differences between 1940s-1960s, and 1970s-1990s. The figurative changes of Korean tableware show the similar trends to the transitional aspects of the society. Design is the manifestation of aesthetic modes which have been developed in a close relationship to society and especially economy. In Korea the development of design was initiated by the economic growth and the Korean aesthetic modes were also changed with the economic growth. The transitional shift of aesthetic modes shown in the figurative characteristics of tableware which are divided on the basis of 1960s and 1970s was peak in 1970s with the development of economy and design started in 1960s.