• Title/Summary/Keyword: $A^*$ search algorithm

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A Weapon Assignment Algorithm Using the Munkres Optimal Assignment Method (Munkres 최적할당 기법을 적용한 무기할당 알고리즘)

  • Kim, Ji-Eun;Shin, Jin-Hwa;Cho, Kil-Seok
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.1
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    • pp.1-8
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    • 2010
  • This paper presents global and optimal solution for weapon assignment problems using the Munkres assignment algorithm. We propose a new modeling method of weapon assignment problems concerning some constraints of weapon systems. In this paper, we compares the Munkres weapon assignment algorithm with two other algorithms employing a search tree model in terms of computational complexity and performance. One is an optimal algorithm using exhausted search and the other is a greedy algorithm which selects the first search result as a solution. The experiment results show that the Munkres weapon assignment algorithm has better performance and less computational complexity in comparison with the two other algorithms.

Fast Detection of Forgery Image using Discrete Cosine Transform Four Step Search Algorithm

  • Shin, Yong-Dal;Cho, Yong-Suk
    • Journal of Korea Multimedia Society
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    • v.22 no.5
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    • pp.527-534
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    • 2019
  • Recently, Photo editing softwares such as digital cameras, Paintshop Pro, and Photoshop digital can create counterfeit images easily. Various techniques for detection of tamper images or forgery images have been proposed in the literature. A form of digital forgery is copy-move image forgery. Copy-move is one of the forgeries and is used wherever you need to cover a part of the image to add or remove information. Copy-move image forgery refers to copying a specific area of an image itself and pasting it into another area of the same image. The purpose of copy-move image forgery detection is to detect the same or very similar region image within the original image. In this paper, we proposed fast detection of forgery image using four step search based on discrete cosine transform and a four step search algorithm using discrete cosine transform (FSSDCT). The computational complexity of our algorithm reduced 34.23 % than conventional DCT three step search algorithm (DCTTSS).

A Study on the Fast Search Algorithm for Vector Quantization (벡터 양자화를 위한 고속 탐색 알고리듬에 관한 연구)

  • 지상현;김용석;이남일;강상원
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.4
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    • pp.293-298
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    • 2003
  • In this paper. we propose a fast search algorithm for nearest neighbor vector quantization (NNVQ). The proposed algorithm rejects those codewords which can not be the nearest codeword and reduces the search range of codebook. Hence it reduces computational time and complexity in encoding process, while it provides the same SD performance as the conventional full search algorithm. We apply the proposed algorithm to the adaptive multi-rate (AMR) speech coder and a general vector quantizer designed by LBG. algorithm. Simulation results show effectiveness of the proposed algorithm.

An Improvement Video Search Method for VP-Tree by using a Trigonometric Inequality

  • Lee, Samuel Sangkon;Shishibori, Masami;Han, Chia Y.
    • Journal of Information Processing Systems
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    • v.9 no.2
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    • pp.315-332
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    • 2013
  • This paper presents an approach for improving the use of VP-tree in video indexing and searching. A vantage-point tree or VP-tree is one of the metric space-based indexing methods used in multimedia database searches and data retrieval. Instead of relying on the Euclidean distance as a measure of search space, the proposed approach focuses on the trigonometric inequality for compressing the search range, which thus, improves the search performance. A test result of using 10,000 video files shows that this method reduced the search time by 5-12%, as compared to the existing method that uses the AESA algorithm.

Optimal Acoustic Search Path Planning Based on Genetic Algorithm in Discrete Path System (이산 경로 시스템에서 유전알고리듬을 이용한 최적음향탐색경로 전략)

  • CHO JUNG-HONG;KIM JUNG-HAE;KIM JEA-SOO;LIM JUN-SEOK;KIM SEONG-IL;KIM YOUNG-SUN
    • Journal of Ocean Engineering and Technology
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    • v.20 no.1 s.68
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    • pp.69-76
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    • 2006
  • The design of efficient search path to maximize the Cumulative Detection Probability(CDP) is mainly dependent on experience and intuition when searcher detect the target using SONAR in the ocean. Recently with the advance of modeling and simulation method, it has been possible to access the optimization problems more systematically. In this paper, a method for the optimal search path calculation is developed based on the combination of the genetic algorithm and the calculation algorithm for detection range. We consider the discrete system for search path, space, and time, and use the movement direction of the SONAR for the gene of the genetic algorithm. The developed algorithm, OASPP(Optimal Acoustic Search Path Planning), is shown to be effective, via a simulation, finding the optimal search path for the case when the intuitive solution exists. Also, OASPP is compared with other algorithms for the measure of efficiency to maximize CDP.

A Proposal of Descent Multi-point Search Method and Its Learning Algorithm for Optimum Value (최적치 계산을 위한 점감다점탐색법과 그 학습 알고리즘의 제안)

  • 김주홍;공휘식;이광직
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.8
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    • pp.846-855
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    • 1992
  • In this paper, the decrease multipoint search method and Its learning algorithm for optimum value computatlon method of object function Is proposed. Using this method, the number of evaluation point according to searching time can t)e reduced multipoint of the direct search method by applying the unlivarlate method. And the learning algorithm can reprat the same search method in a new established boundary by using the searched result. In order to Investigate the efficience of algorithm, this method this method is applied to Rosenbrock and Powell, Colvelle function that are Impossible or uncertain in traditional direct search method. And the result of application, the optimum value searching oil every function Is successful. Especially, the algorithm is certified as a good calculation method for producing global(absolute) optimum value.

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A Study of Survivable Alternate Routing Algorithm (생존성있는 대체 경로 라우팅 알고리즘 연구)

  • Park, Young-Chul
    • Journal of KIISE:Computing Practices and Letters
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    • v.13 no.7
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    • pp.535-539
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    • 2007
  • We study an degree of alternativeness and a survivability of alternate routing algorithm in mobile ad-hoc tactical communication networks. The common channel signaling scheme is used and flood search routing algorithm is used for analysis. We also study a connectivity performance for flood search routing, restricted flooding and hybrid routing. From the results we expect low blocking probabilities with alternate routing and the conventional flood search routing shows better connectivity performance which results in high survivability.

Direction-Oriented Fast Full Search Algorithm at the Divided Search Range (세분화된 탐색 범위에서의 방향 지향적 전영역 고속 탐색 알고리즘)

  • Lim, Dong-Young;Park, Sang-Jun;Jeong, Je-Chang
    • Journal of Broadcast Engineering
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    • v.12 no.3
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    • pp.278-288
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    • 2007
  • We propose the fast full search algorithm that reduces the computational load of the block matching algorithm which is used for a motion estimation in the video coding. Since the conventional spiral search method starts searching at the center of the search window and then moves search point to estimate the motion vector pixel by pixel, it is good for the slow motion picture. However we proposed the efficient motion estimation method which is good for the fast and slow motion picture. Firstly, when finding the initial threshold value, we use the expanded predictor that can approximately calculate minimum threshold value. The proposed algorithm estimates the motion in the new search order after partitioning the search window and adapt the directional search order in the re-divided search window. At the result, we can check that the proposed algorithm reduces the computational load 94% in average compared to the conventional spiral full search algorithm without any loss of image quality.

Structural Optimization Using Tabu Search in Discrete Design Space (타부탐색을 이용한 이산설계공간에서의 구조물의 최적설계)

  • Lee, Kwon-Hee;Joo, Won-Sik
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.5
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    • pp.798-806
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    • 2003
  • Structural optimization has been carried out in continuous or discrete design space. Methods for continuous design have been well developed though they are finding the local optima. On the contrary, the existing methods for discrete design are extremely expensive in computational cost or not robust. In this research, an algorithm using tabu search is developed fur the discrete structural designs. The tabu list and the neighbor function of the Tabu concepts are introduced to the algorithm. It defines the number of steps, the maximum number for random searches and the stop criteria. A tabu search is known as the heuristic approach while genetic algorithm and simulated annealing algorithm are attributed to the stochastic approach. It is shown that an algorithm using the tabu search with random moves has an advantage of discrete design. Furthermore, the suggested method finds the reliable optimum for the discrete design problems. The existing tabu search methods are reviewed. Subsequently, the suggested method is explained. The mathematical problems and structural design problems are investigated to show the validity of the proposed method. The results of the structural designs are compared with those from a genetic algorithm and an orthogonal array design.

Sensor Node Deployment in Wireless Sensor Networks Based on Tabu Search Algorithm (타부 서치 알고리즘 기반의 무선 센서 네트워크에서 센서 노드 배치)

  • Jang, Kil-woong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.5
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    • pp.1084-1090
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    • 2015
  • In this paper, we propose a Tabu search algorithm to efficiently deploy the sensor nodes for maximizing the network sensing coverage in wireless sensor networks. As the number of the sensor nodes in wireless sensor networks increases, the amount of calculation for searching the solution would be too much increased. To obtain the best solution within a reasonable execution time in a high-density network, we propose a Tabu search algorithm to maximize the network sensing coverage. In order to search effectively, we propose some efficient neighborhood generating operations of the Tabu search algorithm. We evaluate those performances through some experiments in terms of the maximum network sensing coverage and the execution time of the proposed algorithm. The comparison results show that the proposed algorithm outperforms other existing algorithms.