• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.524-525
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• 2009

Heavy-weight impact noise(HN) is the most irritating noise in Korean apartment houses. It has been proclaimed standard floor system of 210mm thick slab with isolation material in the wall type structure. But this regulation is applied only new construction field and is not considered remodeling field. In general, the LN can be reduced by using isolation material but HN is known as relating with stiffness, strength & boundary condition of slab. Therefore it is difficulty in improving the HN on remodeling field. In this study, We conducted the reinforcement of concrete slab using C.F.S.(carbon fiber sheet), steel plate and steel beam after on-dol with isolation material on the remodeling field. As the test results, It appeared using C.F.S was no improved but using steel plate & steel beam were a little improved on HN.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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• pp.356-363
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• 2001

The friction pendulum type seismic isolation system (FPS) using the PTFE based materials has been developed to provide a simple and effective way to achieve earthquake resistance for buildings. PTFE matrials are soft and apt to be deformed easily after a few working cycles. Instead of the usual PTFE materials, the Polyimide material was used in this research. Polyimide is harder than PTFE, but has smaller friction coefficient and longer duration fur usage. In this paper, various kinds of PTFE materials were tested to define the frictional characteristics compared with the Polyimide material. FPS was manufactured with fine surface roughness and used with Polyimide material to show the seismic isolation efficiency, and life duration when applied to a rigid mass model and a 5 stole frame model.

• Earthquakes and Structures
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• 제24권3호
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• pp.193-204
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• 2023

The concept of meta-material-based isolation systems (MMIS) for structural columns has been revisited in the present study in order to enhance the stability of rubber pads by using steel shim reinforced rubber (SSRR) layers. Analytical calculations have shown a significant improvement in the stability of MMIS with SSRR pads. Finite element analysis has also been conducted to further show the reduced response of a bridge with the modified MMIS under excitations having frequencies within the corresponding attenuation zone (AZ) as compared to the response of a conventional bridge without MMIS. FE analysis further shows the stress generated on the bridge with MMIS systems are within safe limits. Finally, a generalized procedure has been developed to design bridge columns with the proposed modified MMIS.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.91-92
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• 2005

The electromagnetic coupling effect in standard CMOS process is simulated and evaluated. EM coupling transfer characteristic between planar spiral inductors by isolation methode in standard CMOS have simulated and measured. Measurement results show that suppression of EM coupling effect by ground guardring. The evaluated structures are fabricated 1P5M(one poly, five metal) 0.25um standard CMOS process. These measurement results provide a isolation design guidelines in standard CMOS process for Rf coupling suppression.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.84-85
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• 2005

Dislocations are often found at Shallow Trench Isolation (STI) process after repeated thermal cycles. The residual stress after STI process often leads defect like dislocation by post STI thermo-mechanical stress. Thermo-mechanical stress induced by STI process is difficult to remove perfectly by plastic deformation at previous thermal cycles. Embedded flash memory process is very weak in terms of post STI thermo-mechanical stress, because it requires more oxidation steps than other devices. Therefore, dislocation-free flash process should be optimized.

• Structural Engineering and Mechanics
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• 제48권6호
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• pp.809-822
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• 2013

Base isolation is widely used in seismic resisting buildings due to its low construction cost, high reliability, mature theory and convenient usage. However, it is difficult to design the isolation layer in high-rise buildings using the available bearings because high-rise buildings are characterized with long period, low horizontal stiffness, and complex re-distribution of the internal forces under earthquake loads etc. In this paper, a simple and innovative isolation bearing, named Teflon-based lead rubber isolation bearing, is developed to address the mentioned problems. The Teflon-based lead rubber isolation bearing consists of friction material and lead rubber isolation bearing. Hence, it integrates advantages of friction bearings and lead rubber isolation bearings so that improves the stability of base isolation system. An experimental study was conducted to validate the effectiveness of this new bearing. The effects of vertical loading, displacement amplitude and loading frequency on the force-displacement relationship and energy dissipation capacity of the Teflon-based lead rubber isolation bearing were studied. An analytical model was also proposed to predict the force-displacement relationship of the new bearing. Comparison of analytical and experimental results showed that the analytical model can accurately predict the force-displacement relationship and elastic shear deflection of the Teflon-based lead rubber isolation bearings.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.437-444
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• 2006

Recently, as large structures become lighter and more flexible, the necessity of structural control for reducing excessive displacement and acceleration due to seismic excitation is increased. As a means to minimize seismic damages, various base isolation systems are adopted or considered for adoption. In this study, a base isolation system using Magneto-Sensitive(MS) rubbers is proposed and shown to effectively protect structures against earthquakes. The MS Rubber is a class of smart controllable materials whose mechanical properties change instantly by the application of a magnetic field To demonstrate the advantages of this approach, the MS Rubber isolation system is compared to Lead-Rubber Bearing(LRB) isolation systems and judged based on computed responses to several historical earthquakes. The MS Rubber isolation system is shown to achieve notable decreases in base drifts over comparable passive systems with no accompanying increase in base shears or in accelerations imparted to the superstructure.

• 한국소음진동공학회논문집
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• 제20권11호
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• pp.1046-1051
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• 2010

This paper presents design and performance evaluation of magnetorheological(MR) damper for integrated isolation mount. The MR damper needs two functions for the integrated isolation mount. The one is vibration absorption and the other is isolation of vibration transmission. For vibration absorption, the MR damper requires wide damping force range. And for isolation of vibration transmission, the friction of MR damper needs to be eliminated. In order to achieve this goal, a novel type of MR damper is originally designed in this work. Subsequently, the MR damper is mathematically modeled and its damping force characteristics are evaluated. In addition, the vibration control performance of the MR damper associated with the stage mass is evaluated. From the result, this paper evaluates the performance of MR damper for integrated isolation mount.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.415-420
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• 2000

This paper describes a part of the results obtained in the process of the development of thin sound isolation sheets filled mineral compound powder with PVC. The raw materials used are pyrophillite, pottery stone and graphite. The physical properties such as the crystal structures, compositions, and specific gravities, etc. of raw materials are analyzed and discussed from a point of view of sound isolation material. From the analysis of experimental results, the particle size and the additive amount of mineral compound powder for manufacturing sample isolation sheets are decided. The resistant capability against fire of sound isolation sheets including mechanical, thermal and physical properties is tested. The transmission loss measuremenst of sound isolation sheets are performed using two-microphone method in an impedance tube. It is shown that the sound isolation capability of thin sheets has an excellent performance in excess of the object of development.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.421-424
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• 2004

As the deep sub-micron devices are recently integrated high package density, novel process method for sub $0.1{\mu}m$ devices is required to get the superior thin gate oxide characteristics and reliability. However, few have reported on the electrical quality and reliability on the thin gate oxide. In this paper I will recommand a novel shallow trench isolation structure for thin gate oxide $30{\AA}$ of deep sub-micron devices. Different from using normal LOCOS technology, novel shallow trench isolation have a unique 'inverse narrow channel effects' when the channel width of the devices is scaled down shallow trench isolation has less encroachment into the active device area. Based on the research, I could confirm the successful fabrication of shallow trench isolation(STI) structure by the SEM, in addition to thermally stable silicide process was achiever. I also obtained the decrease threshold voltage value of the channel edge and the contact resistance of $13.2[\Omega/cont.]$ at $0.3{\times}0.3{\mu}m^2$. The reliability was measured from dielectric breakdown time, shallow trench isolation structure had tile stable value of $25[%]{\sim}90[%]$ more than 55[sec].