• Title/Summary/Keyword: vector computer

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Total Ordering Algorithm over Reliable Multicast Protocol using Token Passing Mechanism (멀티캐스트 프로토콜상에서 토큰 전달 방법을 이용한 전체 순서화 알고리즘)

  • Won, Yu-Jae;Yu, Gwan-Jong
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.8
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    • pp.2158-2170
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    • 1999
  • It has been required more reliable communication on processes and improvement of system performance as distributed systems using multicast protocol became widespread. In distributed environment maintaining data consistency through asynchronous execution of processes and coordinating the activities of them would occurs. This paper proposes a total ordering algorithm, TORMP, in order to resolve these problems. TORMP takes advantage of multicast protocol and uses an effective token passing method. It reduces a process delaying time before transmitting its message by multicasting a token simultaneously to every process that initiates the request of the message. Moreover, the processes receiving the token start multicasting the message at the same time, which causes to cut down the overall transmission dely. In case that one process sends a message, TORMP hardly uses the procedure of controlling for ordering. It gives fairly the right of sending messages to all processes in a group with utilizing vector clock. In TORMP, unlike other algorithms, the number of packets generated during ordering process does not depend on the number of processes.

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Analysis of Quadratically Filtered Gradient Algorithm with Application to Channel Equalization (채널 등화기에 응용한 제2차 필터화 경사도 알고리즘의 해석)

  • 김해정;이두수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.1
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    • pp.131-142
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    • 1994
  • This paper analyzes the properties of such algorithm that corresponds to the nonlinear adaptive algorithm with additional update terns, parameterized by the scalar factors ${\alpha}1,\;and\;{\alpha}2$. The analysis of concergence leads to eigenvalues of the transition matrix for the mean filter coefficient vector. Regions in which the algorithm becomes stable are demonstrated. The time constant is derived and the computational complexity of the QFG algorithm is compared with those of the conventional LMS. sign, and LFG algorithm. The properties of convergence in the mean square error is derived and the neccessary condition for the CFG algorithm to be stable is attaned. In the computer simulation a channel equalization is utilized to demonstrate the performance feature of the QFG algorithm. The QFG algorithm has the more computational complexities but the faster convergence speed than LMS and LFG algorithm. Since the QFG algorithm has smoother convergence, it may be useful in case where error bursting is a problem.

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Fast On-Road Vehicle Detection Using Reduced Multivariate Polynomial Classifier (축소 다변수 다항식 분류기를 이용한 고속 차량 검출 방법)

  • Kim, Joong-Rock;Yu, Sun-Jin;Toh, Kar-Ann;Kim, Do-Hoon;Lee, Sang-Youn
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.8A
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    • pp.639-647
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    • 2012
  • Vision-based on-road vehicle detection is one of the key techniques in automotive driver assistance systems. However, due to the huge within-class variability in vehicle appearance and environmental changes, it remains a challenging task to develop an accurate and reliable detection system. In general, a vehicle detection system consists of two steps. The candidate locations of vehicles are found in the Hypothesis Generation (HG) step, and the detected locations in the HG step are verified in the Hypothesis Verification (HV) step. Since the final decision is made in the HV step, the HV step is crucial for accurate detection. In this paper, we propose using a reduced multivariate polynomial pattern classifier (RM) for the HV step. Our experimental results show that the RM classifier outperforms the well-known Support Vector Machine (SVM) classifier, particularly in terms of the fast decision speed, which is suitable for real-time implementation.

COMPUTER SIMULATION OF INTRAMOLECULAR HYDROGEN TRANSFER TO CARBONYL OXYGEN BY A MONTE CARLO METHOD: PHOTOREACTIONS VIA REMOTE PROTON TRANSFER IN BENZOYLBENZOATES

  • Hasegawa, Tadashi;Yamazaki, Yuko;Yoshioka, Michikazu
    • Journal of Photoscience
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    • v.4 no.2
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    • pp.61-67
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    • 1997
  • The model based on the idea that the p$_y$-orbital of the carbonyl oxygen is responsible to receiving hydrogen was devised for simulation of intramolecular hydrogen transfer. A Monte Carlo method was applied to free rotation of a molecular chain performed by changing the dihedral angles, and a "hit" was defined as the case when the migrating hydrogen comes within the region defined as the p$_y$-orbital and satisfies all the geometrical requirements for abstraction. A set of parameters was employed for defining the region and the requirements; $\tau$ was defined as the angle formed between O...H vector and its projection on the mean plane of the carbonyl group (- 43$\circ$ < $\tau$ < + 43$\circ$), $\Delta$ as the C=O...H angle (90 -15$\circ$ < $\Delta$ < 90 + 15$\circ$), $\theta$ as the O...H - C angle ( 180 - 80$\circ$< 0 < 180 + 80$\circ$), d as the distance from the center of the lobe of the p$_y$-orbital to hydrogen (0 < d < 1.04 ${\AA}$). The minimum value for the distance between carbonyl oxygen (O$_1$) and the migrating hydrogen (H$_i$) and for that between non-bonded atoms except the pair of O$_1$ and H$_i$ were assumed to be 0.52 ${\AA}$ and 1.54 ${\AA}$, respectively. The apphcation of this model to intramolecular $\beta$-, $\gamma$-, $\delta$-, $\epsilon$-, and $\zeta$-hydrogen abstraction in ketones and $\eta$- and $\theta$- proton transfer in oxoesters gave good results reflecting their photochemical behavior. The model was also used for prediction of photoreactivities of 2-(N,N-dibenzylamino)ethyl 2-, 3- and 4-benzoylbenzoate (1a - c). (1a - c).

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Steering Control and Geomagnetism Cancellation for an Autonomous Vehicle using MR Sensors

  • Kim, Hong-Reol;Son, Seok-Jun;Kim, Tae-Gon;Kim, Jeong-Heui;Lim, Young-Cheol;Kim, Eui-Sun;Chang, Young-Hak
    • Journal of Sensor Science and Technology
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    • v.10 no.5
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    • pp.329-336
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    • 2001
  • This paper describes the steering control and geomagnetism cancellation for an autonomous vehicle using an MR sensor. The magneto-resistive (MR) sensor obtains the vector summation of the magnetic fields from embedded magnets and the Earth. The vehicle is controlled by the magnetic fields from embedded magnets. So, geomagnetism is the disturbance in the steering control system. In this paper, we propose a new method of the sensor arrangement in order to remove the geomagnetism and vehicle body interference. The proposed method uses two MR sensors located in a level plane and the steering controller has been developed. The controller has three input variables ($dB_x$, $dB_y$, $dB_z$) using the measured magnetic field difference, and an output variable (the steering angle). A simulation program was developed to acquire the data to teach the neural network, in order to test the ability of a neural network to learn the steering control process. Also, the computer simulation of the vehicle (including vehicle dynamics and steering) was used to verify the steering performance of the vehicle controller using the neural network. From the simulation and field test, good result was obtained and we confirmed the robustness of the neural network controller in a real autonomous vehicle.

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Aggregate Resources Management and Transport Route Analysis Using GIS (골재자원의 관리 및 수송경로 분석을 위한 GIS 활용 연구)

  • 이윤종;이동영;신은선
    • The Journal of Engineering Geology
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    • v.4 no.2
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    • pp.169-186
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    • 1994
  • A GIS technique was developed for aggregate resources management and transport route analysis. In the study, the management of aggregate resources deals with resources evaluation and control of aggregate supply. The computer system was specially designed for this analysis on the basis of relational database model, and it was named ARIS(Aggregate Resources Information System). A Vector database for this study area of Chungcheong - Do was established for analysis of ARIS. In network analysis, there are many essential elements such as road name, speed limit and width, turns and stops etc. Impedance was also measured for the resistance against transportation of aggregate resources. Actually, the impedances are attributes of arcs, turns and stops. Finally, the feasibility of ARIS was tested to use as a decision making tool of aggregate resources management.

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Cloning and Expression of a Yeast Cell Wall Hydrolase Gene (ycl) from Alkalophilic Bacillus alcalophilus subsp. YB380

  • Ohk, Seung-Ho;Yeo, Ik-Hyun;Yu, Yun-Jung;Kim, Byong-Ki;Bai, Dong-Hoon
    • Journal of Microbiology and Biotechnology
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    • v.11 no.3
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    • pp.508-514
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    • 2001
  • A stuructural gene (ycl) encoding novel yeast cell wall hydrolase, YCL, was cloned from alkalophilic Bacillus alcalophilus subsp. YB380 by PCR, and transformed into E. coli JM83. Based on the N-terminal and internal amino acid sequences of the enzyme, primers were designed for PCr. The positive clone that harbors 1.8 kb of the yeast cell wall hydrolase gene was selected by the colony hybridization method with a PCR fragment as a probe. According to the computer analysis, this gene contained a 400-base-paired N-terminal domain of the enzyme. Based on nucletide homology of the cloned gene, a 850 bp fragment was amplified and the C-terminal domain of the enzyme was sequenced. With a combination of the two sequences, a full nucleotide sequence for YCL was obtained. This gene, ycl, consisted of 1,297 nucleotides with 27 nucleotides with 27 amino acids of signal sequence, 83 redundant amino acids of prosequence, and 265 amino acids of the mature protein. This gene was then cloned into the pJH27 shuttle vector and transformed into the Bacillus subtilis DB104 to express the enzyme. It was confirmed that the expressed cell wall hydrolase that was produced by Bacillus subtilis DB104 was the same as that of the donor strain, by Western blot using polyclonal antibody (IgY) prepared from White Leghorn hen. Purified yeast cell wall hydrolase and expressed recombinant protein showed a single band at the same position in the Western blot analysis.

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The performance enhancement with multiple antenna algorithm between indoor and outdoor wireless communication (옥내와 옥외간 무선 통신에서 다중 안테나 알고리즘 적용을 통한 통신 성능 향상)

  • Lee Junho;Lee Yong Up;Seo Youngjun;Baang Sungkeun;Kim Jong Dae
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.5C
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    • pp.355-363
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    • 2005
  • This paper is discussed about the technology of the performance enhancement in the wireless communication between indoor and outdoor environments. In the outdoor wireless communication, the signal has mainly a severe degradation by the fading effect of channel, but that problem may be overcome by using ordinary multiple antenna technology and array signal processing algorithm. Hence, since the channel has the characteristics of both fading and angle spread in the wireless communication between indoor and outdoor, the ordinary technology cannot solve the signal degradation due to the angle spread. In order to solve the problem, in this paper, the characteristic of the wireless channel between indoor and outdoor is first analyzed and considered the channel models fit to that case. We propose the new multiple antenna algorithm by use of mean steering vector concept, and obtained the results of the performance enhancement. With the results of the performance analyses through of the numerical study and computer simulation, we show that the proposed algorithm has more enhanced signal to noise ratio than the previous algorithm.

Two-stage Content-based Image Retrieval Using the Dimensionality Condensation of Feature Vector (특징벡터의 차원축약 기법을 이용한 2단계 내용기반 이미지검색 시스템)

  • 조정원;최병욱
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.7C
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    • pp.719-725
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    • 2003
  • The content-based image retrieval system extracts features of color, shape and texture from raw images, and builds the database with those features in the indexing process. The search in the whole retrieval system is defined as a process which finds images that have large similarity to query image using the feature database. This paper proposes a new two-stage search method in the content-based image retrieval system. The method is that the features are condensed and stored by the property of Cauchy-Schwartz inequality in order to reduce the similarity computation time which takes a mostly response time from entering a query to getting retrieval results. By the extensive computer simulations, we have observed that the proposed two-stage search method successfully reduces the similarity computation time while maintaining the same retrieval relevance as the conventional exhaustive search method. We also have observed that the method is more effective as the number of images and dimensions of the feature space increase.

An Improved Ordering Method for MIMO Signal Detection Using QR Decomposition and Successive Interference Cancellation (QR 분해 및 순차적 간섭제거 기반의 MIMO 신호검출 기법을 위한 향상된 순서화 방법)

  • Bak, Sang-Hyun;Kim, Jae-Kwon;Yang, Won-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.10C
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    • pp.1010-1015
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    • 2009
  • In this paper, we propose a novel detection ordering technique for MIMO signal detection methods based on QR decomposition and successive interference cancellation (SIC). Recently, new signal detection methods for spatially multiplexed (SM) MIMO systems were proposed, where all the constellation points are tried as the first layer symbol, and the remaining layer symbols are estimated via SIC, producing candidate vectors. Finally, the ML metric values are calculated for the candidate vectors, that are again used to select the best symbol vector. It was also shown that the ordering method in the conventional V-BLAST is not suitable to these signal detection methods. In this paper, we propose a novel ordering method, and we show via computer simulations that the proposed ordering method improves the error performance.