• 펄프종이기술
• /
• 제30권1호
• /
• pp.59-70
• /
• 1998

A steady-state molecular diffusion experiment was conducted to evaluate the water vapor proof properties of paper Handsheets prepared from unbleached Itraft pulps(UKP) and old newspapers(ONP) and four different types of polymer-laminated white duplex board were tested under appropriate standard conditions. The diffusivity was determined on the basis of the Fickean first law. Results obtained from this study can be summarized as follows ; 1. The diffusivity data for handsheets showed about $10^{-5}cm^2/min$. whereas polymer-laminated paperboards had remarkably improved water-vapor resistance with about $10^3 to 10^4$ times lower diffusivity : 2. Sheet basis weight, wet-swelling and sizing degree had little influence on the diffusivity of paper; 3 Linear relationship existed between sheet density and diffusivity, and, 4. Highly sfgnificant linear relationship could be observed between diffusivity and Darcy s gas permeability. Results indicate that diffusivity, an intrinsic property of paper, can provide a valuable information for precise evaluation and improved quality control of water-vapor proof properties of paper.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1994년도 하계학술대회 논문집 A
• /
• pp.223-225
• /
• 1994

In these days, it is widely applications of Linear Induction Motor(LIM) that used propulsion system of maglev and LIM Car. elevator. conveyor system, servo system, etc. The calibration method for, performance of LIM is more difficult than static state of one. Then we made testing system to measurement for dynamic performance of LIM and deal with data acquisition board on PC system. We try to get for the data measuring that is thrust force, braking force versus speed(r.p.m. or time) and current, voltage, frequency versus speed.

• 천문학논총
• /
• 제30권2호
• /
• pp.593-594
• /
• 2015

We present our analysis results for an updated orbital ephemeris for the dipping low mass X-ray binary 4U 1624-49, using the light curve collected by the All Sky Monitor (ASM) on board the Rossi X-ray Timing Explorer (RXTE) and the Monitor of All-Sky X-ray Image (MAXI). To make clear dip profiles, the light curve from the ASM and the MAXI were divided into ten 500d segments and four 400d segments for ASM and MAXI light curves, respectively, and folded with the linear ephemeris proposed by Smale et al. (2001). The phases of dip centers were determined by the method adopted from Hu et al. (2008). The phase drift was then fitted with a linear function. We obtained an updated orbital period of 0.869896(1) d and a phase zero epoch of JD 2450088.6618(57). No clear orbital period derivative is detected with a 2-sigma upper limit of $1.4{\times}10^{-6}(yr)^{-1}$ from a quadratic curve fitting of the dip phase evolution.

• 농촌의학ㆍ지역보건
• /
• 제26권2호
• /
• pp.97-109
• /
• 2001

1999년 12월과 2000년 2월 사이에 경상북도 일개 농촌지역과 어촌지역 주민들 중 연구에 참여하기를 원하는 2,840명을 연구대상으로 선정하였다. 대상자의 신장, 체중, 그리고 공복 시 총콜레스테롤을 측정하였으며 신장과 체중을 이용하여 비만도를 계산하였다. 설문지를 이용하여 연령, 성별, 흡연, 음주, 그리고 폐경 상태(여성)를 면담 조사하였다. 어촌남성의 총콜레스테롤 평균치는 191.6mg/dl, 농촌남성이 173.6mg/dl이었고, 어촌여성은 206.9mg/dl, 농촌지여성은 186.9mg/ dl였다. 단순분석결과, 남성에서는 지역, 비만도, 그리고 흡연습관이 유의한 변수였다(p<0.01). 여성에서는 지역(p<0.01), 연령(p<0.01), 비만도(p<흡연습관(p<0.05), 그리고 폐경상태(p<유의한 변수였다. 총콜레스테롤치를 종속변수로 한 다중선형회귀분석을 실시한 결과, 남성에서는 어촌지역이 농촌지역에 비해(p<비만할수록(p<0.01) 총콜레스테롤은 유의하게 높았다. 여성에서는 어촌지역이 농촌지역에 비해(p<0.01), 비만할수록(p<0.01), 폐경여성이 정상에 비해(p<총콜레스테롤은 유의하게 높았다. 이와 같이 어촌지역이 농촌지역에 비해 총콜레스테롤치가 높았으며 남녀 모두에서 총콜레스테롤과 관련된 중요한 변수는 비만도였다.

• 대한원격탐사학회지
• /
• 제13권2호
• /
• pp.85-98
• /
• 1997

본 논문에서는 현재 고해상도 위성 영상을 촬영하는 대부분의 카메라인 pushbroom형태 의 선형 CCD카메라의 기하학적 모델 및 좌표변환 과정을 제안한다. 제안되는 모델은 원시 영상 자표계로 부터 지도 좌표계까지의 정함수 변환 뿐아니라 반대 방향의 역함수 변환도 포함한다. 실제로 resampling의 용이성이나 구현의 효율성을 감안할 때 역함수 변환이 사용되어야 하지만, pushbroom형태의 영상일 경우 그 촛점의 위치가 시간에 따라 변화하므로 역함수 변환 함수가 단 순한 수학적 형태로 성립될 수 없다. 따라서 이 논문에서는 반복 연산과 수렴을 통한 역함수 변 환의 유도를 제안한다. 제안되는 기하학적 모델은 모든 선형 CCD 위성영상에 적용될 수 있으나 본 논문에서는 유도의 편이성을 위해 현재 비행모델을 제작 중이며 1998년 후반에 발사 예정인 우리별 3호의 고해상도 카메라 영상에 촛점을 맞추었다.

• Smart Structures and Systems
• /
• 제8권4호
• /
• pp.367-384
• /
• 2011

This paper presents the design and experimental evaluation of fast output sampling feedback controller to minimize structural vibration of a cantilever beam using Shape Memory Alloy (SMA) wires as control actuators and piezoceramics as sensor and disturbance actuator. Linear dynamic models of the smart cantilever beam are obtained using online recursive least square parameter estimation. A digital control system that consists of $Simulink^{TM}$ modeling software and dSPACE DS1104 controller board is used for identification and control. The effectiveness of the controller is shown through simulation and experimentation by exciting the structure at resonance.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
• /
• pp.199-202
• /
• 1998

This paper describe an intelligent cruise control system for automobile. With the remarkable numerical increase of automobiles on the road, the optimized traffic flow control using the cruise control is one of the very important traffic problems to overcome the limitation of an existing road capacity. Based on this idea that minimize the fuel cost and the air pollution, and accept a driver's needs for driving, we have developed an intelligent cruise control system for vehicle. This proposed intelligent fuzzy cruise controller was successfully implemented using the fuzzy algorithm, the i80c196 μ-controller board and the throttle valve actuator. The field test results on an linear road was introduced.

• 대한기계학회논문집A
• /
• 제26권2호
• /
• pp.267-274
• /
• 2002

Using a flexible rotating beam test bed, experimental verification of a flexible multibody dynamic simulations for a rotating beam model has been carried out. The test bed consists of a flexible arm, harmonic driver reducer, AC servo motor and DSP board with PC. The mechanical ports of the test bed has been designed using 3D CAD program. For the simulation model, mass and moment of inertia of each part of the flexible rotating beam test bed are also obtained from 3D CAD model. In the flexible multibody dynamic simulations, the substructuring model has been established to capture nonlinear effects of the flexible rotating beam. Through the experimental verification, substructuring model provides better results than those from the linear model in the high speed rotation.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2000년도 전력전자학술대회 논문집
• /
• pp.620-623
• /
• 2000

A very simple control approach using neural network for the robust position control of a Permanent Magnet Synchronous Motor(PMSM) is presented The linear quadratic controller plus feedforward neural network is employed to obtain the robust PMSM system approximately linearized using field-orientation method for an AC servo. The neural network is trained in on-line phases and this neural network is composed by a fedforward recall and error back-propagation training. Since the total number of nodes are only eight this system can be easily realized by the general microprocessor. During the normal operation the input-output response is sampled and the weighting value is trained multi-times by error back-propagation method at each sample period to accommodate the possible variations in the parameters or load torque. And the state space analysis is performed to obtain the state feedback gains systematically. IN addition the robustness is also obtained without affecting overall system response. This method is realized by a floating-point Digital Singal Processor DS1102 Board (TMS320C31) The basic DSP software is used to write C program which is compiled by using ANSI-C style function prototypes.

• 한국정밀공학회지
• /
• 제16권2호통권95호
• /
• pp.164-175
• /
• 1999

If the camera plane is nearly parallel to the calibration board on which objects are defined, most of existing calibration approaches such as Tsai's radial-alignment-constraint method cannot be applied. Recently, for such an ill-conditioned case, Zhuang & Wu suggested the linear two-stage calibration algorithm assuming that the exact values of focal length and scale factor are known a priori. In this paper, we developed an iterative two-stage algorithm starts with initial guess fo the two parameters to determine the value of the others using Zhuang & Wu's method. In the second stage, the two parameters are locally optimized. This process is repeated until any improvement cannot be expected any more. The performance comparison between Zhuang & Wu's method and our algorithm shows the superiority of ours. Also included are the computational results for the effects of the distribution and the number of calibration points on the calibration performance.