• 제목/요약/키워드: prediction technique

검색결과 2,053건 처리시간 0.027초

무인항공기 비행 상태 예측을 위한 개선된 CNN-LSTM 혼합모델 (An Improved CNN-LSTM Hybrid Model for Predicting UAV Flight State)

  • 서현우;최은주;김병수;문용호
    • 항공우주시스템공학회지
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    • 제18권3호
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    • pp.48-55
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    • 2024
  • 최근에 무인항공기의 사업화가 활발하게 추진됨에 따라 무인항공기의 안전성 확보를 위한 기술 개발에 많은 관심이 집중되고 있다. 일반적으로 무인항공기는 운용 중 급기동, 외란, 조종사 실수 등으로 인하여 조종 불능의 상태로 진입할 가능성을 지닌다. 조종 불능 상태로의 진입을 예방하기 위해서는 무인항공기의 비행 상태를 예측하는 것이 필수적으로 요구된다. 본 논문에서는 무인항공기의 비행 상태 예측 성능의 향상을 위하여 개선된 CNN-LSTM 혼합모델을 제안한다. 모의실험은 제안하는 모델을 이용한 예측 기법이 기존 예측 기법에 비하여 비행 상태 예측 성능이 우수하며 온보드 환경에서 실시간으로 운용됨을 보인다.

Prediction Accuracy Evaluation of Domain and Domain Combination Based Prediction Methods for Protein-Protein Interaction

  • Han, Dong-Soo;Jang, Woo-Hyuk
    • Bioinformatics and Biosystems
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    • 제1권2호
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    • pp.128-133
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    • 2006
  • This paper compares domain combination based protein-protein interaction prediction method with domain based protein-protein interaction method. The prediction accuracy and reliability of the methods are compared using the same prediction technique and interaction data. According to the comparison, domain combination based prediction method has showed superior prediction accuracy to domain based prediction method for protein pairs with fully overlapped domains with protein pairs in learning sets. When we consider that domain combination based method has the effects of assigning a weight to each domain interaction, it implies that we can improve the prediction accuracies of currently available domain or domain combination based protein interaction prediction methods further by developing more advanced weight assignment techniques. Several significant facts revealed from the comparative studies are also described in this paper.

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Hybrid radiation technique of frequency-domain Rankine source method for prediction of ship motion at forward speed

  • Oh, Seunghoon;Kim, Booki
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제13권1호
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    • pp.260-277
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    • 2021
  • The appropriate radiation conditions of ship motion problem with advancing speed in frequency domain are investigated from a theoretical and practical point of view. From extensive numerical experiments that have been conducted for evaluation of the relevant radiation conditions, a hybrid radiation technique is proposed in which the Sommerfeld radiation condition and the free surface damping are mixed. Based on the comparison with the results of the translating and pulsating Green function method, the optimal damping factor of the hybrid radiation technique is selected, and the observed limitations of the proposed hybrid radiation technique are discussed, along with its accuracy obtained from the numerical solutions. Comparative studies of the forward-speed seakeeping prediction methods available confirm that the results of applying the hybrid radiation technique are relatively similar to those obtained from the translating and pulsating Green function method. This confirmation is made in comparisons with the results of solely applying either the free surface damping, or the Sommerfeld radiation condition. By applying the proposed hybrid radiation technique, the wave patterns, hydrodynamic coefficients, and motion responses of the Wigley III hull are finally calculated, and compared with those of model tests. It is found that, in comparison with the model test results, the three-dimensional Rankine source method adopting the proposed hybrid radiation technique is more robust in terms of accuracy and numerical stability, as well as in obtaining the forward speed seakeeping solution.

Cognitive Radio Based Spectrum Sharing: Evaluating Channel Availability via Traffic Pattern Prediction

  • Li, Xiukui;Zekavat, Seyed A. (Reza)
    • Journal of Communications and Networks
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    • 제11권2호
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    • pp.104-114
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    • 2009
  • In this paper, a technique is proposed that enables secondary users to evaluate channel availability in cognitive radio networks. Here, secondary users estimate the utilization of channels via predicting the traffic pattern of primary user, and select a proper channel for radio transmission. The proposed technique reduces the channel switching rate of secondary users (the rate of switching from one channel to another) and the interference on primary users, while maintaining a reasonable call blocking rate of secondary users.

SEA 기법을 이용한 보강 원통형 셸의 수중방사소음 해석 (Waterborne Noise Prediction of the Reinforced Cylindrical Shell Using the SEA Technique)

  • 배수룡;전재진;이헌곤
    • 소음진동
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    • 제3권2호
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    • pp.155-161
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    • 1993
  • The vibration generated by the machinery on board is transmitted to the hull and into the water. At the early design stage, the prediction of the hull vibration and the radiated noise level is very important to reduce their levels. In this study, SAE(Statistical Energy Analysis) technique is applied to predict structureborne noise level of the hull considering fluid loading. Rayleigh integral is applied to predict the radiated noise level. The results of comparision between the predictions and measurements for the reinforced cylindrical shell have shown good agreements.

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UPS inverter의 2차 데드비트 응답을 위한 반복부하예측기법 (Repetitive Load Prediction for Second Order Deadbeat Response Applied to UPS Inverter)

  • 최재호
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2000년도 전력전자학술대회 논문집
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    • pp.339-342
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    • 2000
  • Repetitive Load Prediction is proposed for the UPS inverter application of the second order deadbeat controller which is robust against the calculation time delay and the parameter variation and which gets fast response against the load variation. The proposed technique predicts the load current ahead of two sampling time using that the load current is periodic. This is effective under nonlinear load condition. The proposed technique is derived theoretically and verified through simulation and experimental result.

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Zero-Order 압축 방식에서 ECG 데이터 압축률 예측과 적용에 관한 연구 (A Study on Prediction and Application of ECG Data Compression Rate at Zero-Oder Compression)

  • 안형민;김영길
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.513-516
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    • 1999
  • I here are many kinds of method to compress data. To very simple methods from very complex methods, a kind is various. In this study, the simplest form of the Tolerance-Comparison method, zero-order method is used. Using this method, despite using low speed CPUs, it is possible to compress real time data. So this method is suitable for ECG holler system. In this study, to complement zero-order method, it is needed to develop prediction technique and to research ways to apply the technique.

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다시점 예측 기법을 이용한 디지털 홀로그램의 압축 기술 (Digital Hologram Compression Technique using Multi-view Prediction Method)

  • 최현준;서영호;배진우;유지상;김동욱
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.413-414
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    • 2006
  • In this paper, we propose an efficient coding method of digital hologram (or fringe pattern) using multi-view prediction technique based on video and image coding standard such as MPEG. The proposed algorithm illustrates that it has better properties for reconstruction and higher compression rate than the previous researches.

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CORRELATION ANALYSIS METHOD OF SENSOR DATA FOR PREDICTING THE FOREST FIRE

  • Shon Ho Sun;Chi Jeong Hee;Kim Eun Hee;Ryu Keun Ho;Jung Doo Yeong;kim Kyung Ok
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.186-188
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    • 2005
  • Because forest fire changes the direction according to the environmental elements, it is difficult to predict the direction of it. Currently, though some researchers have been studied to which predict the forest fire occurrence and the direction of it, using the remote detection technique, it is not enough and efficient. And recently because of the development of the sensor technique, a lot of In-Situ sensors are being developed. These kinds of In-Situ sensor data are used to collect the environmental elements such as temperature, humidity, and the velocity of the wind. Accordingly we need the prediction technique about the environmental elements analysis and the direction of the forest fire, using the In-Situ sensor data. In this paper, as a technique for predicting the direction of the forest fire, we propose the correlation analysis technique about In-Situ sensor data such as temperature, humidity, the velocity of the wind. The proposed technique is based on the clustering method and clusters the In-Situ sensor data. And then it analyzes the correlation of the multivariate correlations among clusters. These kinds of prediction information not only helps to predict the direction of the forest fire, but also finds the solution after predicting the environmental elements of the forest fire. Accordingly, this technique is expected to reduce the damage by the forest fire which occurs frequently these days.

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아파트 단지의 수평 및 수직 환경 소음 예측 (Prediction of Environmental Noise in Apartment Complex)

  • 김정태;유혜영;정형일;장동운
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 춘계학술대회논문집
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    • pp.1050-1055
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    • 2001
  • A software for prediction of apartment noise level ihas been improved. The program is based on the ray tracing technique which has been widely used in the environmental noise analysis and prediction. Especially for prediction of environmental noise in apartment complex, this program is advanced in the graphics routine by bilinear interpolation. In this paper, we analyze the railway noise distribution in apartment environment and develop a 3D graphics routine for illustrating the noise level.

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