• Title/Summary/Keyword: redundant structure

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An Empirical Investigation of Agency Costs in the Determination of Performance of Pakistani Nonfinancial Sector

  • Siddiqui, Muhammad Ayub;Afzal, Usman
    • Journal of Distribution Science
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    • v.10 no.5
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    • pp.19-28
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    • 2012
  • The study examines the performance and its relationship with capital structure and agency cost with respect to the industrial configurations and economic groups of Pakistan Economy. The study employs data set of 334 listed joint stock companies from the nonfinancial sectors for the period of 1999-2009 from cotton and textile, engineering, chemical, sugar, cement, fuel and energy, paper and board, transport and communication, and miscellaneous economic groups. Pooled data from the Panel data methodology has been applied to observe the significance of different performance measures through determinant of capital structure and agency costs with special focus on the leverage and cash flows as the direct determinant and interactive variables. The empirical test results using redundant variable tests demonstrate support for agency theory in the context of Pakistan's industrial configurations. The implications of the study point towards more investigations on the subject using industrial configurations as control and moderating variables.

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Reviving GOR method in protein secondary structure prediction: Effective usage of evolutionary information

  • Lee, Byung-Chul;Lee, Chang-Jun;Kim, Dong-Sup
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2003.10a
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    • pp.133-138
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    • 2003
  • The prediction of protein secondary structure has been an important bioinformatics tool that is an essential component of the template-based protein tertiary structure prediction process. It has been known that the predicted secondary structure information improves both the fold recognition performance and the alignment accuracy. In this paper, we describe several novel ideas that may improve the prediction accuracy. The main idea is motivated by an observation that the protein's structural information, especially when it is combined with the evolutionary information, significantly improves the accuracy of the predicted tertiary structure. From the non-redundant set of protein structures, we derive the 'potential' parameters for the protein secondary structure prediction that contains the structural information of proteins, by following the procedure similar to the way to derive the directional information table of GOR method. Those potential parameters are combined with the frequency matrices obtained by running PSI-BLAST to construct the feature vectors that are used to train the support vector machines (SVM) to build the secondary structure classifiers. Moreover, the problem of huge model file size, which is one of the known shortcomings of SVM, is partially overcome by reducing the size of training data by filtering out the redundancy not only at the protein level but also at the feature vector level. A preliminary result measured by the average three-state prediction accuracy is encouraging.

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Fault Detection System Design and HILS Evaluation for the Smart UAV FCS

  • Nam, Yoon-Su;Jang, Hu-Yeong;Hong, Sung-Kyung;Park, Sung-Su
    • International Journal of Control, Automation, and Systems
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    • v.5 no.1
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    • pp.104-109
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    • 2007
  • This paper is about a redundancy management system design for the Smart UAV(unmanned aerial vehicle) which utilizes the tilt..rotor mechanism. In order to meet the safety requirement on the PLOC(probability of loss of control) of $1.7{\times}10^{-5}$ per flight hour for FCS (flight control system) failures, a digital FCS is mechanized with a dual redundant structure. A fault detection system which is composed of a CCM(cross channel monitor) and analytic redundancy using the Kalman filtering is designed, and its effectiveness is evaluated through experiments. A threshold level and persistence count for managing redundant sensors are designed based on the statistical analysis of the FCS sensors. To increase the survivability of the UAV after the loss of critical sensors in the SAS(stability augmentation system) and to provide reference information for a tie-breaking condition at which an ILM(in-line monitor) cannot distinguish the faulty channel between two operating ones, the Kalman filter approach is investigated.

Parameterized IP Core of Complex-Number Multiplier (파라미터화된 복소수 승산기 IP 코어)

  • 양대성;이승기;신경욱
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.05a
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    • pp.307-310
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    • 2001
  • A parameterized complex-number multiplier (PCMUL) core IP (Intellectual Property), which can be used as an essential arithmetic unit in baseband signal processing of digital communication systems, is described. The bit-width of the multiplier is parameterized in the range of 8-b~24-b and is user-selectable in 2-b step. The PCMUL_GEN, a core generator with GUI, generates VHDL code of a CMUL core for a specified bit-width. The IP is based on redundant binary (RB) arithmetic and a new radix4 Booth encoding/decoding scheme proposed in this paper. It results in a simplified internal structure, as well as high-speed, low-power, and area-efficient implementation. The designed IP was verified using Xilinx FPGA board.

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Voting System Bus Protocol for a Highly-Reliable PLC with Redundant Modules (다중화 구조 고신뢰성 제어기기를 위한 보팅 시스템버스 프로토콜)

  • Jeong, Woohyuk;Park, Jaehyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.6
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    • pp.689-694
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    • 2014
  • An SPLC (Safety Programmable Logic Controller) must be designed to meet the highest safety standards, IEEE 1E, and should guarantee a level of fault-tolerance and high-reliability that ensures complete error-free operation. In order to satisfy these criteria, I/O modules, communication modules, processor modules and bus modules of the SPLC have been configured in triple or dual modular redundancy. The redundant modules receive the same data to determine the final data by the voting logic. Currently, the processor of each rx module performs the voting by deciding on the final data. It is the intent of this paper to prove the improvement on the current system, and develop a voting system for multiple data on a system bus level. The new system bus protocol is implemented based on a TCN-MVB that is a deterministic network consisting of a master-slave structure. The test result shows that the suggested system is better than the present system in view of its high utilization and improved performance of data exchange and voting.

An Efficient Resource Reservation Scheme based on Gray-Cell in Wireless Mobile Networks (그레이 셀을 이용한 무선 이동 네트워크에서의 효율적인 자원 예약 방안)

  • 노희경;장문정;김태은;이미정
    • Journal of KIISE:Information Networking
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    • v.31 no.2
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    • pp.146-157
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    • 2004
  • In order to provide continuous QoS guaranteed to a mobile user, it is required to deploy some kind of mechanisms which reserves resources in advance at the locations to which the mobile user is expected to move. An important issue with regards to these mechanisms is to minimize the waste of resources caused by redundant reservations while keeping up the QoS guaranteed services to the user In this paper, we propose a wireless network domain structure which deploys a special cell, called “a gray cell”. The boundaries of two or more neighboring domains are surrounded by the gray cells, and the gray cells are supposed to belong to all of its neighboring domains. Based on this wireless domain structure, we propose a mechanism which completely removes the waste of redundant resource reservation in the wireless network domain while greatly reducing the risk of reservation disruption caused by inter-domain handover. Using simulation, it is shown that the proposed mechanism can deal with inter-domain handover as effectively as it does with intra-domain handover. It is also presented that the proposed mechanism outperforms existing mechanisms with respect to reservation disruption time and packet losses caused by handovers.

System Optimization Technique using Crosscutting Concern (크로스커팅 개념을 이용한 시스템 최적화 기법)

  • Lee, Seunghyung;Yoo, Hyun
    • Journal of Digital Convergence
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    • v.15 no.3
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    • pp.181-186
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    • 2017
  • The system optimization is a technique that changes the structure of the program in order to extract the duplicated modules without changing the source code, reuse of the extracted module. Structure-oriented development and object-oriented development are efficient at crosscutting concern modular, however can't be modular of crosscutting concept. To apply the crosscutting concept in an existing system, there is a need to a extracting technique for distributed system optimization module within the system. This paper proposes a method for extracting the redundant modules in the completed system. The proposed method extracts elements that overlap over a source code analysis to analyze the data dependency and control dependency. The extracted redundant element is used to program dependency analysis for the system optimization. Duplicated dependency analysis result is converted into a control flow graph, it is possible to produce a minimum crosscutting module. The element extracted by dependency analysis proposes a system optimization method which minimizes the duplicated code within system by setting the crosscutting concern module.

Synchronization Method Design of Redundant Flight Control Computer for UAV (무인기를 위한 이중화 비행제어컴퓨터의 동기화 설계)

  • Lee, Young Seo;Kang, Shin Woo;Lee, Hee Gon;Ahn, Tae-Sik
    • Journal of Advanced Navigation Technology
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    • v.25 no.4
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    • pp.273-279
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    • 2021
  • A flight control computer(FLCC) applied to an unmanned aerial vehicle(UAV) is a safety-critical item, and which is designed in a multiple structure to increase the reliability of operation by securing fault tolerance. These FLCC of multiple structure should be designed so that each independent processing/control components can perform the same operation at the same time. And for this reason, a synchronization algorithm for synchronizing the operation between FLCCs should be included in an operational flight program. In this paper, we propose a software design method for synchronization between dual FLCCs applied to UAVs. The proposed synchronization method is designed to synchronize using only the minimum hardware resources to reduce a failure rate. In addition, the proposed synchronization method is designed to minimized synchronization errors due to a timer operation by designing in consideration of operation characteristics of the hardware timer used for the synchronization.

Analysis on Human Musculoskeletal Structures with Application to Design of Adjustable Spring Mechanisms (인체의 근육구조에 대한 해석과 가변스프링 메커니즘 설계로의 적용)

  • 이병주;이재훈;김희국
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.2
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    • pp.208-219
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    • 1999
  • Springs have been employed in a wide range of mechanical systems. This work deals with the concept of an adaptable spring mechanism which can arbitrarily modulate its spring characteristics. The adaptable spring is desired for enhancing performances of various mechanical systems employing springs. We demonstrate that such adaptable springs can be realized by adapting anthropomorphic musculoskeletal structures of the human upper-extremity, which possesses highly nonlinear kinematic-coupling among redundant muscles existing in its structures. This phenomenon has been explained by several human arm models. Based on the analysis results, we propose multi-degree-of-freedom spring mechanisms resembling the musculoskeletal structure of the human upper-extremity, and verifiy the applicability of these mechanisms through simulation.

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A Implementation of a Line Scan System for Continuous Manufacturing Process (연속 생산 라인에서의 고속 라인 스캔 검사 시스템 구축)

  • Lim, Cheung;Lee, Jong-Min;Kim, Yong-Deak
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.211-214
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    • 2002
  • Under a continuous manufacturing process, two dimension inspection system causes problems as blurring effect and low resolution and requires position calibration between frames. One dimension inspection system is, therefore, being researched as a substitution. In this paper, we implement mechanism of switching memory and processing data for reasonable one dimension inspection system. Redundant weft image and noise was suggested to be reduced by new method using modified morphological process and masked erosion process. From resulting image, line data and possible error information were obtained and constructed as a structure. Finally, error detecting algorithm was performed with this data structure. Processing time of error detecting was 0.625ms per line in applied system and experiment showed 94.7% of error detecting ability. This method is 20% faster in speed and 2.7% higher in error detecting ability comparing with the present method.

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