• Journal of Institute of Control, Robotics and Systems
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• v.7 no.5
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• pp.384-392
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• 2001

In this paper, we propose a novel robust fault isolation filter design method using the left eigenstructure assignment scheme proposed by the authors. The proposed method guarantees that the ${\gamma}$ simultaneous faults can be isolated when the number of available outpur measurements is ${\gamma}$. Moreover, if there exist redundant output measurements, the eigenvaluses of te filter system can be assigned to the desired position or the filter can be designed robustly to, the system parameter variation. Liu & Si developed a filter design method which has the same purpose, fault isolation. However their method cannot use the redundant freedom of the output matrix C. The proposed filter can use the redundant freedom of the matrix C effectively. Beside this in this paper, an eigenstructure assignment methodology that satisfies the required fault isolation conditions is also proposed. The proposed fault isolation filter was applied for isolating the simultaneous faults to a VTOL aircraft in order to verify the fault isolation performance.

• International Journal of Concrete Structures and Materials
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• v.9 no.4
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• pp.439-451
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• 2015

This study analyzed the isolation effect for a 15-story reinforced concrete (RC) building with regard to changes in the beam-column stiffness ratio and the difference in the vibration period between the superstructure and an isolation layer in order to provide basic data that are needed to devise a framework for the design of isolated RC buildings. First, this analytical study proposes to design RC building frames by securing an isolation period that is at least 2.5 times longer than the natural vibration period of a superstructure and configuring a target isolation period that is 3.0 s or longer. To verify the proposed plan, shaking table tests were conducted on a scaled-down model of 15-story RC building installed with laminated rubber bearings. The experimental results indicate that the tested isolated structure, which complied with the proposed conditions, exhibited an almost constant response distribution, verifying that the behavior of the structure improved in terms of usability. The RC building's response to inter-story drift (which causes structural damage) was reduced by about one-third that of a non-isolated structure, thereby confirming that the safety of such a superstructure can be achieved through the building's improved seismic performance.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.6
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• pp.1032-1037
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• 2016

In this paper, the method of isolation enhancement for the mobile phone MIMO antenna of LTE class 40(2300~2400MHz) was studied. Design of MIMO antenna was based on the hybrid antenna that operates both a monopole and an IFA(Inverted F Antenna). A structure for the isolation enhancement which controls induced electric field on the ground plane is located between MIMO antenna, and was not connected with the ground but apart 0.3mm. A MIMO antenna that operates on class 3~40(1710~2400MHz) of LTE service bands and a structure for the isolation enhancement at the class 10 band were designed. VSWR measurement of implemented antenna on the FR4 board showed within 3:1 at entire design bands, and isolation between antennas at the class 40 band was less than -30dB. Isolation was enhanced more than 20dB by the studied structure. ECC(Envelope Correlation Coefficient) for MIMO performance was under 0.1, and antenna average gain and efficiency measured in the anechoic chamber were -4.28~-1.40dBi and 37.32~72.36% respectively.

• Nuclear Engineering and Technology
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• v.50 no.1
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• pp.170-181
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• 2018

Because of the design and construction requirements, the nuclear structures need to maintain the structural integrity under both design state and extreme earthquake shaking. The base-isolation technology can significantly reduce the damages of structures under extreme earthquake events, and effectively protect the safeties of structures and internal equipment. This study proposes a base-isolation design for the AP1000 nuclear shield building on considering the performance requirements of the seismic isolation systems and devices of shield building. The seismic responses of isolated and nonisolated shield buildings subjected to design basis earthquake (DBE) shaking and beyond-design basis earthquake (BDBE) shaking are analyzed, and three different strategies for controlling the displacements subjected to BDBE shaking are performed. By comparing with nonisolated shield buildings, the floor acceleration spectra of isolated shield buildings, relative displacement, and base shear force are significantly reduced in high-frequency region. The results demonstrate that the base-isolation technology is an effective approach to maintain the structural integrity which subjected to both DBE and BDBE shaking. A displacement control design for isolation layers subjected to BDBE shaking, which adopts fluid dampers for controlling the horizontal displacement of isolation layer is developed. The effectiveness of this simple method is verified through numerical analysis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.547-548
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• 2013

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.562-563
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• 2011

• Archives of Pharmacal Research
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• v.5 no.1
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• pp.7-12
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• 1982

Ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf and Rg1 were effectively isolated from ginseng root by preparative liquid chromatography (LC) on two PrepPAK-500/c18 cartridges in series and semipreparative LC on a .mu. Bondapak cabohydrate analysis column, a .mu.Bondapak C18 column or a .mu. Porasil column. The identities of the isolated ginsenosides were confirmed by analytical high-performance liquid chromatography (HPLC) and infrared spectrophotometry. By this method large scale isolation of pure ginsenosides was efficiently accomplished.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.10
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• pp.1002-1008
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• 2009

We consider a double faults detection and isolation problem using modified extended parity space approach for inertial measurement unit which use redundant inertial sensors. A redundant IMU which has a hardware redundant is composed of the cone shape because it is good for fault detection and isolation. We analyze the type of double faults and the reason why fault isolation performance is low. We propose modified extended parity space approach method using EPSA and the difference of sensor data.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.3
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• pp.51-60
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• 1998

Base isolation is an innovative design strategy that provides a practical alternative for the seismic design of structures. Base isolators, mainly employed to isolate large structures subjected to earthquake ground excitations and to rehabilitate structures damaged by past earthquakes, deflect and absorb the seismic energy horizontally transmitted to the structures. This study demonstrated that the base isolation system may offer effective performance for bridges during severe seismic events through shaking table tests. Two base isolation systems using laminated rubber bearings with and without hydraulic dampers are tested. The test results strongly show that the laminate rubber bearings cause the natural period of the bridge structure increased considerably, which results in the deck acceleration and the shear forces on the deck acceleratino and the shear forces on the piers reduced significantly. The results also demonstrate that the hydraulic dampers enhance the system's capacity in dissipating energy to reduce the relative displacement between the bridge deck and the pier.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1772-1777
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• 2000

The Combat Computer Consoles installed in surface ships should endure harsh environment such as vibration from engine or propeller and shock from underwater explosion. Generally, commercial isolation mounts are selected and used for anti-vibration and anti-shock design. In this research, the environment of the Combat Computer Console was analyzed first. Selected proper mount was modeled and computer simulation was performed to emulate the environment test. The real environment test was conducted with a manufactured Combat Computer Console. The test results were same as the simulation and satisfied the performance requirements. The computer simulation proved to be a useful design tool to predict the performance before the final environment test.