• Title/Summary/Keyword: divide and conquer

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Embedding Complete binary trees in Binomial trees (완전이진트리의 이항트리에 대한 임베딩)

  • 윤수민;최정임형석
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.289-292
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    • 1998
  • Trees are the underlying structure for divide-and-conquer algorithms and the graphs that provide the solution spaces for NP-complete problems. Complete binary trees are the basic structure among trees. Therefore, if complete binary trees can be embedded in binomial trees, the algorithms which are provided by complete binary trees can be performed efficiently on the interconnection networks which have binomial trees as their subgraphs or in which binomial trees can be embedded easily. In this paper, we present dilation 2 embedding of complete binary trees in binomial trees.

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A study on the analysis method of Petri Net Models Using the Transitive Matrix (추이적 행렬을 이용한 패트리 넷 모델의 분석방법에 대한 연구)

  • 송유진;이종근
    • Journal of the Korea Society for Simulation
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    • v.10 no.1
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    • pp.13-24
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    • 2001
  • We propose a divide-conquer method of Petri nets under the condition of one-boundedness for all the Petri nets. We introduce the P-invariant transitive matrix of Petri nets and relationship between them. The feature of the P-invariant transitive matrix is that each element stands for the transitive relationship between input place and output place through the firing of the enable transition.

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Analysis of Petri net models using Transitive Matrix

  • Song, Yu-Jin;Lee, Jong-kun
    • Proceedings of the IEEK Conference
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    • 2000.07b
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    • pp.665-668
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    • 2000
  • In this paper, we are focused on the analysis of Petri nets model using the subnet. Specially, we are proposes a divide-conquer method of Petri nets under the condition of one-boundedness for all the Petri nets. The usefulness of the approach is shown by applying the proposed techniques to a illustration model.

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Local Similarity based Discriminant Analysis for Face Recognition

  • Xiang, Xinguang;Liu, Fan;Bi, Ye;Wang, Yanfang;Tang, Jinhui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.11
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    • pp.4502-4518
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    • 2015
  • Fisher linear discriminant analysis (LDA) is one of the most popular projection techniques for feature extraction and has been widely applied in face recognition. However, it cannot be used when encountering the single sample per person problem (SSPP) because the intra-class variations cannot be evaluated. In this paper, we propose a novel method called local similarity based linear discriminant analysis (LS_LDA) to solve this problem. Motivated by the "divide-conquer" strategy, we first divide the face into local blocks, and classify each local block, and then integrate all the classification results to make final decision. To make LDA feasible for SSPP problem, we further divide each block into overlapped patches and assume that these patches are from the same class. To improve the robustness of LS_LDA to outliers, we further propose local similarity based median discriminant analysis (LS_MDA), which uses class median vector to estimate the class population mean in LDA modeling. Experimental results on three popular databases show that our methods not only generalize well SSPP problem but also have strong robustness to expression, illumination, occlusion and time variation.

A New Low Complexity Multi-Segment Karatsuba Parallel Multiplier over $GF(2^n)$ (유한체 $GF(2^n)$에서 낮은 공간복잡도를 가지는 새로운 다중 분할 카라슈바 방법의 병렬 처리 곱셈기)

  • Chang Nam-Su;Han Dong-Guk;Jung Seok-Won;Kim Chang Han
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.41 no.1
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    • pp.33-40
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    • 2004
  • The divide-and-conquer method is efficiently used in parallel multiplier over finite field $GF(2^n)$. Leone Proposed optimal stop condition for iteration of Karatsuba-Ofman algerian(KOA). Ernst et al. suggested Multi-Segment Karatsuba(MSK) method. In this paper, we analyze the complexity of a parallel MSK multiplier based on the method. We propose a new parallel MSK multiplier whose space complexity is same to each other. Additionally, we propose optimal stop condition for iteration of the new MSK method. In some finite fields, our proposed multiplier is more efficient than the KOA.

Face Spoofing Attack Detection Using Spatial Frequency and Gradient-Based Descriptor

  • Ali, Zahid;Park, Unsang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.2
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    • pp.892-911
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    • 2019
  • Biometric recognition systems have been widely used for information security. Among the most popular biometric traits, there are fingerprint and face due to their high recognition accuracies. However, the security system that uses face recognition as the login method are vulnerable to face-spoofing attacks, from using printed photo or video of the valid user. In this study, we propose a fast and robust method to detect face-spoofing attacks based on the analysis of spatial frequency differences between the real and fake videos. We found that the effect of a spoofing attack stands out more prominently in certain regions of the 2D Fourier spectra and, therefore, it is adequate to use the information about those regions to classify the input video or image as real or fake. We adopt a divide-conquer-aggregate approach, where we first divide the frequency domain image into local blocks, classify each local block independently, and then aggregate all the classification results by the weighted-sum approach. The effectiveness of the methodology is demonstrated using two different publicly available databases, namely: 1) Replay Attack Database and 2) CASIA-Face Anti-Spoofing Database. Experimental results show that the proposed method provides state-of-the-art performance by processing fewer frames of each video.

Development of an Operation Software for the ASRI-FMS/CIM (ASRI-FMS/CIM 을 위한 운용 소프트웨어의 구축)

  • Park, Chan-Kwon;Park, Jin-Woo;Kang, Suk-Ho
    • IE interfaces
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    • v.6 no.2
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    • pp.53-65
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    • 1993
  • This paper deals with the development of a software module for production planning and scheduling activities of an existing Flexible Machining and Assembly System (FMAS). The Production Planning Module uses the hierarchical and sequential scheme based on "divide and conquer" philosophy. In this module, routes are determined based on the production order, orders are screened, tools are allocated, and order adjustments are executed according to the allocated tools. The Scheduling Module allocates the resources, determines the task priority and the start and completion times of tasks. Re-scheduling can be done to handle unforeseen situations such as lumpy demands and machine breakdowns. Since all modules are integrated with a central database and they interface independently, it is easy to append new modules or update the existing modules. The result of this study is used for operating the real FMAS consisting of a machining cell with 2 domestic NC machines and a part feeding robot, an assembly cell with a conveyor and 3 robots, an inspection cell, an AGV, an AS/RS, and a central control computer.

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A Comparison of Decentralized and Partially Observed Supervisors: Application to a CIM Testbed (분산 감독제어기와 부분관측 감독제어기의 비교: CIM Testbed 응용)

  • Son, Hyoung-Il;Lee, Suk
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.11
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    • pp.1155-1164
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    • 2008
  • Supervisory control theory, which was first proposed by Ramadge and Wonahm, is a well-suited control theory for the control of complex systems such as semiconductor manufacturing systems, automobile manufacturing systems, and chemical processes because these are better modeled by discrete event models than by differential or difference equation models at higher levels of abstraction. Moreover, decentralized supervisory control is an efficient method for large complex systems according to the divide-and-conquer principle. Decentralized supervisors cannot observe the events those of which occur only within the other supervisors. Therefore decentralized supervisors can be designed according to supervisory control theory under partial observation. This paper presents a solution and a design procedure of supervisory control problem (SCP) for the case of decentralized control and SCP under partial observation (SCPPO). We apply the proposed design procedure to an experimental CIM Testbed. And we compare and analyze the designed decentralized supervisors and partially observed supervisors.

Proteolytic cleavages of MET: the divide-and-conquer strategy of a receptor tyrosine kinase

  • Fernandes, Marie;Duplaquet, Leslie;Tulasne, David
    • BMB Reports
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    • v.52 no.4
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    • pp.239-249
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    • 2019
  • Membrane-anchored full-length MET stimulated by its ligand HGF/SF induces various biological responses, including survival, growth, and invasion. This panel of responses, referred to invasive growth, is required for embryogenesis and tissue regeneration in adults. On the contrary, MET deregulation is associated with tumorigenesis in many kinds of cancer. In addition to its well-documented ligand-stimulated downstream signaling, the receptor can be cleaved by proteases such as secretases, caspases, and calpains. These cleavages are involved either in MET receptor inactivation or, more interestingly, in generating active fragments that can modify cell fate. For instance, MET fragments can promote cell death or invasion. Given a large number of proteases capable of cleaving MET, this receptor appears as a prototype of proteolytic-cleavage-regulated receptor tyrosine kinase. In this review, we describe and discuss the mechanisms and consequences, both physiological and pathological, of MET proteolytic cleavages.

One-to-All Broadcasting in Petersen-Torus Networks for SLA and MLA Models

  • Seo, Jung-Hyun;Lee, Hyeong-Ok
    • ETRI Journal
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    • v.31 no.3
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    • pp.327-329
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    • 2009
  • In a network, broadcasting is the dissemination of a message from a source node holding a message to all the remaining nodes through a call. This letter proposes a one-to-all broadcasting algorithm in the Petersen-torus network PT(n, n) for the single-link-available and multiple-link-available models. A PT(n, n) is a regular network whose degree is 4 and number of nodes is $10n^2$, where the Petersen graph is set as a basic module, and the basic module is connected in the form of a torus. A broadcasting algorithm is developed using a divide-and-conquer technique, and the time complexity of the proposed algorithm approximates n+4, the diameter of PT(n, n), which is the lower bound of the time complexity of broadcasting.

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