• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2000년도 가을 학술발표논문집 Vol.27 No.2 (2)
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• pp.529-531
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• 2000

본 논문은 Geometry Compression 분야에서 다뤄지는 압축기법 중 delta encoding 과정을 보완하여 좀 더 높은 압축률을 얻고자 하는 vertex position prediction 과정에 대한 내용으로 구성되어 있다. 이것은 triangle strip 형태의 입력을 받아서 그 vertex data 중 position 정보들간의 delta encoding 과정을 예측 기법을 이용한 encoding 과정으로 대체하여 Huffman encoding 과정에서의 symbol 개수를 줄여 압축률을 향상시키자는 개념에서 출발한다. triangle strip 생성 기법 중 greedy algorithm을 적용한 후, 기존의 parallelogram 방식과 이 논문에서 새로이 제안하는 방식을 비교하여 보다 나은 압축 방식을 제시하는 것이 이 논문의 목적이다. 이 논문에서 제시하는 방식을 실험한 결과, 기존의 예측 기법에 비해 2.4% 정도의 향상을 보여주고 있다.

• Journal of Positioning, Navigation, and Timing
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• 제3권2호
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• pp.83-90
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• 2014

In this study, to improve an existing ground-wave based time broadcasting system, a study that predicts the field distribution and field strength of the transmitted signal of a new ground-wave based time broadcasting system was performed. The prediction area was assumed to be the Korean peninsula; and to reflect the mountainous terrain of the Korean peninsula in the prediction of the variations of field distribution and field strength, a new prediction method based on the Monteath model was proposed and utilized. As field distribution changes depending on the position of a transmitter station, potential sites for the transmitter station were selected considering the geographical characteristics. In this regard, the ground conductivity information of North Korea cannot be obtained, and thus, the ground conductivity of the North Korean region was reflected considering the geological characteristics of South Korea and North Korea. Based on this, the variations of field distribution and field strength were predicted by setting the Korean peninsula as the prediction area, and the prediction results depending on the position of the transmitter station were discussed.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 추계학술대회
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• pp.53-54
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• 2015

The maritime industry is expanding at an alarming rate and as such there is a perpetual need to improve situation awareness in the maritime environment using new and emerging technology. Tracking is one of the numerous ways of enhancing situation awareness by providing information that may be useful to the operator. The tracking system described herein comprises determining existing states of own ship, state prediction and state compensation caused by random noise. The purpose of this paper is to analyze the process of tracking and develop a tracking algorithm by using ${\alpha}-{\beta}-{\gamma}$ tracking filter under a random noise or irregular motion for use in a warship. The algorithm involves initializing the input parameters of position, velocity and course. The actual positions are then computed for each time interval. In addition, a weighted difference of the observed and predicted position at the nth observation is added to the predicted position to obtain the smoothed position. This estimation is subsequently employed to determine the predicted position at (n+1). The smoothed values, predicted values and the observed values are used to compute the twice distance root mean square (2drms) error as a measure of accuracy of the tracking module.

• Journal of Biosystems Engineering
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• 제33권1호
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• pp.21-29
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• 2008

In this study, the thermal properties of peeled chestnuts were measured, and the mathematical prediction model of freezing time was also developed for various interior positions from center to rind (surface). The measured thermal properties were showed that heat conductivity is $0.43W/m^{\circ}C$, specific heat is $2.7206J/m^3^{\circ}C$, latent heat is $216.9{\times}10^6J/m^3$ and freezing point is $-2.8^{\circ}C$. The entire process about reaching to the freezing time of peeled chestnuts was analyzed with its each regular depth position using the finite difference method (FDM) based on computer simulation. In case of regular freezing temperature, it was showed an that surface (rind) position is more rapidly reached into the freezing point rather than the center position, and also reaching time to the freezing point is more fast at the lower freezing temperature. Comparison results between simulation and experiments showed linear relationship. In regularly varying condition for freezing temperature, this method would give an information to predict a freezing time of the interior points for peeled chestnuts and more similar agricultural products.

• 대한치과교정학회지
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• 제33권1호
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• pp.31-39
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• 2003

본 연구는 성장에 의한 변화를 예측하는 현재의 방법이 실제로 골격성 III급 부정교합자의 진단과 치료계획에 적절히 사용될 수 있는지를 판단해 보기 위해 초진 시 골격성 III급 부정교합으로 진단받고 성장 종료 후 악교정 수술을 받기 위해 재내원한 골격성 III급 부정교합자 25명(남자 13명, 여자 12명)을 대상으로 시행되었다. 초진시 채득된 측모 두부방사선 사진에서 Ricketts의 성장예측법을 통해 성장 종료 후의 상태를 예측한 후, 악교정 수술을 위해 재내원 했을 때 채득된 측모 두부방사선 사진에서 계측된 실제 성장량과 비교분석 함으로써 다음과 같은 결론을 얻었다. 1. 예측치와 관측치의 일치정도를 평가해본 결과 Porion Location, Ramus Position, Facial Depth, Facial Axis, Mandibular Plane angle, Maxillary Convexity에서의 예측치가 관측치와 차이를 보이고 있어 이 항목에 대한 Ricketts 성장예측법의 예측치가 실제 성장량을 잘 설명해주지 못함이 관찰되었다. 2. 하악골체의 성장량은 정상 성 장량과 유사하였으나 Porion Location, Ramus Position이 정상적인 성장과정을 벗어나면서 하악골의 전방위치를 유도하였다. 3. 골격성 III급 부정교합자에서는 성장의 양과 방향이 비정상적인 성장변화를 나타내어 정상 성장에서라면 변화를 보이지 않을 하악지의 전방 위치, 하악이부의 전상방 회전등이 일어나 하악 전돌의 경향이 악화될 수 있다.

• 소음진동
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• 제8권6호
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• pp.1023-1029
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• 1998

When one attempts to construct a hologram. one finds that there are many sources of measurement errors. These errors are even amplified if one predicts the pressures close to the sources. The pressure estimation errors depend on the following parameters: the measurement spacing on the hologram plane. the prediction spacing on the prediction plane. and the distance between the hologram and the prediction plane. This raper analyzes quantitatively the errors when these are distributed irregularly on the hologram plane The sensor mismatch and inaccurate measurement location. position mismatch. are mainly addressed. In these cases. one can assume that the measurement is a sample of many measurement events. The bias and random error are derived theoretically. Then the relationship between the random error amplification ratio and the parameters mentioned above is examined quantitatively in terms of energy.

• 제어로봇시스템학회논문지
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• 제16권4호
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• pp.368-373
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• 2010

A new indoor mobile robot localization method is presented. Robot recognizes well designed single color landmarks on the ceiling by vision system, as reference to compute its precise position. The proposed likelihood prediction based method enables the robot to estimate its position based only on the orientation of landmark.The use of single color landmarks helps to reduce the complexity of the landmark structure and makes it easily detectable. Edge based optical flow is further used to compensate for some landmark recognition error. This technique is applicable for navigation in an unlimited sized indoor space. Prediction scheme and localization algorithm are proposed, and edge based optical flow and data fusing are presented. Experimental results show that the proposed method provides accurate estimation of the robot position with a localization error within a range of 5 cm and directional error less than 4 degrees.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.225-226
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• 2012

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.152-155
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• 1991

A solution to the problem of robot manipulator tracking of a smoothly moving object is given. It is shown that fuzzy prediction rule, fuzzy control can compensate the adverse effects of noise, time delay, unknown object trajectory, and robot modeling uncertainty. Simulations show that the fuzzy logic control results in acceptable precision,

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.135-136
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• 2009