• Title/Summary/Keyword: self system

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Direct displacement-based seismic design methodology for the hybrid system of BRBFE and self-centering frame

  • Akbar Nikzad;Alireza Kiani;Seyed Alireza Kazerounian
    • Structural Engineering and Mechanics
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    • v.88 no.5
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    • pp.463-480
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    • 2023
  • The buckling-restrained braced frames with eccentric configurations (BRBF-Es) exhibit stable cyclic behavior and possess a high energy absorption capacity. Additionally, they offer architectural advantages for incorporating openings, much like Eccentrically Braced Frames (EBFs). However, studies have indicated that significant residual drifts occur in this system when subjected to earthquakes at the Maximum Considered Earthquake (MCE) hazard level. Consequently, in order to mitigate these residual drifts, it is recommended to employ self-centering systems alongside the BRBF-E system. In our current research, we propose the utilization of the Direct Displacement-Based Seismic Design method to determine the design base shear for a hybrid system that combines BRBF with an eccentric configuration and a self-centering frame. Furthermore, we present a methodology for designing the individual components of this composite system. To assess the effectiveness of this design approach, we designed 3-, 6-, and 9-story buildings equipped with the BRBF-E-SCF system and developed finite element models. These models were subjected to two sets of ground motions representing the Maximum Considered Earthquake (MCE) and Design Basis Earthquake (DBE) seismic hazard levels. The results of our study reveal that although the combined system requires a higher amount of steel material compared to the BRBF-E system, it substantially reduces residual drift. Furthermore, the combined system demonstrates satisfactory performance in terms of story drift and ductility demand.

IN VITRO MICRO-SHEAR BOND STRENGTH OF FIVE COMPOSITE RESINS TO DENTIN WITH FIVE DIFFERENT DENTIN ADHESIVES (미세-전단 결합 강도 시험을 이용한 상아질 접착제와 수복용 복합 레진의 호환성에 관한 연구)

  • Chung, Jin-Ho;Roh, Byoung-Duck
    • Restorative Dentistry and Endodontics
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    • v.29 no.4
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    • pp.353-364
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    • 2004
  • The purpose of this study was to compare and to evaluate the combination use of 5 kinds of dentin adhesive systems and 5 kinds of composite resins using micro-shear bond test. Five adhesive systems (Prime & Bond NT (PBN). Onecoat bond (OC), Excite (EX), Syntac (SY), Clearfil SE bond (CS)) and five composite resins (Spectrum (SP), Synergy Compact (SC), Tetric Ceram (TC), Clearfil AP-X (CA), Z100 (Z1)) were used for this study ($5{\;}{\times}{\;}5{\;}={\;}25group$, n =14/group). The slices of horizontally sectioned human tooth were bonded with each bonding system and each composite resin, and tested by a micro-shear bond strength test. These results were analyzed statistically. The mean micro-shear bond strength of dentin adhesive systems were in order of CS (22.642 MPa), SY (18.368 MPa), EX (14.599 MPa). OC (13.702 MPa). PBN (12.762 MPa). The mean bond strength of self-etching primer system group (CS, SY) in dentin was higher than that of self-priming adhesive system groups (PBN, EX, OC) significantly (P<0.05). The mean bond strength of composite resins was in order of SP (19.008 MPa), CA (17.532 MPa). SC (15.787 MPa), TC (15.068 MPa). Z1 (14.678 MPa). Micro-shear bond strength of SP was stronger than those of other composite resins significantly (P < 0.05). And those of TC and Z1 were weaker than other composite resins significantly (P < 0.05). No difference was found in micro-shear bond strength of composite resin in self-etching primer adhesive system groups (CS, SY) statistically. However, there was significant difference of micro-shear bond strength of composite resin groups in self-priming adhesive systems group (PBN, EX, OC). The combination of composite resin and dentin adhesive system recommended by manufacturer did not represent positive correlation. It didn't seem to be a significant factor.

A Self-Description File System for NAND Flash Memory (낸드 플래시 메모리를 위한 자기-서술 파일 시스템)

  • Han, Jun-Yeong;Park, Sang-Oh;Kim, Sung-Jo
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.2
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    • pp.98-113
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    • 2009
  • Conventional file systems for harddisk drive cannot be applied to NAND flash memory, because the physical characteristics of NAND flash memory differs from those of harddisk drive. To address this problem, various file systems with better reliability and efficiency have also been developed recently. However, those file systems have inherent overheads for updating the file's metadata pages, because those file systems save file's meta-data and data separately. Furthermore, those file systems have a critical reliability problem: file systems fail when either a page in meta-data of a file system or a file itself fails. In this paper, we propose a self-description page technique and In Memory Core File System technique to address these efficiency and reliability problems, and develop SDFS(Self-Description File System) newly. SDFS can be safely recovered, although some pages fail, and improves write and read performance by 36% and 15%, respectively, and reduces mounting time by 1/20 compared with YAFFS2.

A Small Disk-type Hybrid Self-healing Motor (소형 원판형 하이브리드 자기 부상 모터)

  • ;Yohji Okada
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.11 no.8
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    • pp.338-348
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    • 2001
  • A hybrid self-hearing motor, which Is a functional combination of general permanent magnet (PM) motor and hybrid active magnetic bearing(AMB), was proposed a few years ago. In this paper the hybrid self-bearing motor is modified to a disk type, in which one of two magnetic hearings was substituted for a thin yoke to make the system more compact. An outer rotors in this self-hearing motor is actively controlled only in two radial directions while the ocher motions are passively salable owing to the disk-type structure. Main advantages of the proposed self-hearing motor are simple control mechanism, low power consumption and smart structure. Mathematical model for the magnetic force Is built wish consideration of the radial displacement of the rotor. The model helps us not only to design a levitation controller but also to expect the system performance. Some experimental results show good capability and feasibility of the Proposed self-bearing motor.

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Modeling of Positive Selection for the Development of a Computer Immune System and a Self-Recognition Algorithm

  • Sim, Kwee-Bo;Lee, Dong-Wook
    • International Journal of Control, Automation, and Systems
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    • v.1 no.4
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    • pp.453-458
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    • 2003
  • The anomaly-detection algorithm based on negative selection of T cells is representative model among self-recognition methods and it has been applied to computer immune systems in recent years. In immune systems, T cells are produced through both positive and negative selection. Positive selection is the process used to determine a MHC receptor that recognizes self-molecules. Negative selection is the process used to determine an antigen receptor that recognizes antigen, or the nonself cell. In this paper, we propose a novel self-recognition algorithm based on the positive selection of T cells. We indicate the effectiveness of the proposed algorithm by change-detection simulation of some infected data obtained from cell changes and string changes in the self-file. We also compare the self-recognition algorithm based on positive selection with the anomaly-detection algorithm.

Load Frequency Control of Power System using a Self-tuning Fuzzy PID Controller (자기조정 퍼지 PID제어기를 이용한 전력시스템의 부하주파수 제어)

  • 이준탁
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.1
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    • pp.40-46
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    • 1999
  • A self-tuning FPID(Fuzzy Proportional Intergral Derivative) controller fo load frequency control of 2-area power systemis proposed in this paper. The paramters of the proposed self-tuning FPID controller are self-tuned by the proposed fuzzy inference technique. Therefore in this paper the fuzzy inference technique of PID gains using PSGM(Product Sum Gravity Method) is presented and is applied to the load frequency control of 2-area power system. The computer simulation results show that the proposed controller give better more control characteristics than convention-al PID, FLC under load changes.

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Balancing and Position Control of an Circular Inverted Pendulum System Using Self-Learning Fuzzy Controller (자기학습 퍼지제어기를 이용한 원형 역진자 시스템의 안정화 및 위치 제어)

  • 김용태;변증남
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1996.10a
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    • pp.172-175
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    • 1996
  • In the paper is proposed a hierarchical self-learning fuzzy controller for balancing and position control of an circular inverted pendulum system. To stabilize the pendulum at a specified position, the hierarchical fuzzy controller consists of a supervisory controller, a self-learning fuzzy controller, and a forced disturbance generator. Simulation example shows the effectiveness of the proposed method.

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A Position of a Anti-Air Weapon System for Fighting Ship's Self-Defence Effectiveness Enhancement (대공방어무기체계의 교전 효과도 향상을 위한 함상 배치 위치 분석)

  • Hwang, Soo-Jin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.9 no.3
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    • pp.41-47
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    • 2006
  • Naval combat system is total management system integrating a ship and several weapon system functions. For the mission of a ship, naval combat system manages features and constraints of each weapon system. Proper treats of each weapon system's conditions guarantee effective performances of naval combat system. In this paper, the relationship of anti-air weapon system's on board position and self-defence effectiveness against anti-surface missiles is studied

Self-evaluation model for TQM activity

  • Osada, Hiroshi;Yamazaki, Masahiko
    • International Journal of Quality Innovation
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    • v.1 no.1
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    • pp.75-80
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    • 2000
  • Objective evaluation is necessary for the company to know the level of its TQM activity and to improve it. This article proposes self-evaluation model for TQM activity through comparison study of the examination viewpoints for the Deming Prize with criteria of the Malcolm Baldridge National Quality Award. Proposed self-valuation model consists of three evaluation categories i.e. management system, management performance and survey/audit system. Evaluation on these categories is done for process and performance by using scoring method. This self-evaluation model is useful for checking the progress of TQM and make company recognize the strength and weakness of its TQM activity, namely, positioning analysis.

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A Novel Built-In Self-Test Circuit for 5GHz Low Noise Amplifiers (5GHz 저잡음 증폭기를 위한 새로운 Built-In Self-Test 회로)

  • Ryu Jee-Youl;Noh Seok-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.5
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    • pp.1089-1095
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    • 2005
  • This paper presents a new low-cost Built-In Self-Test (BIST) circuit for 50Hz low noise amplifier (LNA). The BIST circuit is designed for system-on-chip (SoC) transceiver environment. The proposed BIST circuit measures the LNA specifications such as input impedance, voltage gaih, noise figure, and input return loss all in a single SoC environment.