• International Journal of High-Rise Buildings
• /
• v.7 no.3
• /
• pp.233-242
• /
• 2018

Since the response reduction effect on over 200-meter-tall resulting from the seismic isolation system is smaller in general than low-rise and mid-rise buildings, mid-story isolated buildings are considered to reduce the response in the upper part above the isolation story, however, in many cases, the acceleration response just below the isolation story is likely to be the largest. This paper presents the structural design schemes, the design of the main structural frames, and the constructions of a 230-meter-tall super high-rise building with mid-story isolation mechanism integrated in Roppongi, Tokyo. Moreover, this paper shows how the architectural and structural design for integrating a mid-story isolation system in a super high-rise building has been conducted and what solutions have been derived in this project. The realization of this building indicates new possibilities for mid-story isolation design for super high-rise buildings.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.24 no.4
• /
• pp.169-178
• /
• 2020

In a previous paper, ambient vibration tests were conducted on a cable stayed bridge with resilient-friction base isolation systems (R-FBI) to extract the dynamic characteristics of the bridge and compare the results with a seismic analysis model. In this paper, a nonlinear seismic analysis model was established for analysis of the bridge to compare the difference in seismic responses between nonlinear time history analysis and multi-mode spectral analysis methods in the seismic design phase of cable supported bridges. Through these studies, it was confirmed that the seismic design procedures of the "Korean Highway Bridge Design Code (Limit State Design) for Cable Supported Bridges" is not suitable for cable supported bridges installed with R-FBI. Therefore, to reflect the actual dynamic characteristics of the R-FBI installed on cable-supported bridges, an improved seismic design procedure is proposed that applies the seismic analysis method differently depending on the seismic isolation effect of the R-FBI for each seismic performance level.

• Journal of Korean Association for Spatial Structures
• /
• v.19 no.3
• /
• pp.33-40
• /
• 2019

A seismic isolation system is one of the most effective control devices used for mitigating the structural responses due to earthquake loads. This system is generally used as a type of base isolation system for low- and mid-rise building structures. If the base isolation technique is applied to high-rise buildings, a lot of problems may be induced such as the movement of isolation bearings during severe wind loads, the stability problem of bearings under large compression forces. Therefore, a mid-story isolation system was proposed for seismic protection of high-rise buildings. Residence-commerce complex buildings in Korea have vertical irregularity because shear wall type and frame type structures are vertically connected. This problem can be also solved by the mid-story isolation system. An effective analytical method using super elements and substructures was proposed in this study. This method was used to investigate control performance of mid-story isolation system for residence-commerce complex buildings subjected to seismic loads. Based on numerical analyses, it was shown that the mid-story isolation system can effectively reduce seismic responses of residence-commerce complex tall buildings.

• Journal of Information Technology Applications and Management
• /
• v.13 no.4
• /
• pp.141-153
• /
• 2006

According to supply of super high way internet service, importance of security becomes more emphasizing. Therefore, flawless security solution is needed for blocking information outflow when we send or receive data. large enterprise and public organizations can react to this problem, however, small organization with limited work force and capital can't. Therefore they need to elevate their level of information security by improving their information security system without additional money. No hackings can be done without passing invasion blocking system which installed at the very front of network. Therefore, if we manage.isolation log effective, we can recognize hacking trial at the step of pre-detection. In this paper, it supports information security manager to execute isolation log analysis very effectively. It also provides isolation log analysis module which notifies hacking attack by analyzing isolation log.

• Journal of Electrochemical Science and Technology
• /
• v.10 no.2
• /
• pp.244-249
• /
• 2019

SiO has a high theoretical capacity as a promising anode material candidate for high-energy-density Li-ion batteries. However, its practical application is still not widely used because of the large volume change that occurs during cycling. In this report, an active material containing a mixture of SiO and graphite was used to improve the insufficient energy density of the conventional anode with the support of multidimensional conducting agents. To relieve the isolation of the active materials from volume changes of SiO/graphite electrode, two types of conducting agents, namely, 1-dimensional VGCF and 0-dimensional Super-P, were introduced. The combination of VGCF and Super-P conducting agents efficiently maintained electrical pathways among particles in the electrode during cycling. We found that the electrochemical performances of cycleability and rate capability were greatly improved by employing the conducting agent combinations of VGCF and Super-P compared with the electrode using only single VGCF or single Super-P. We investigated the detailed failure mechanisms by using systematic electrochemical analyses.

• The Magazine of the IEIE
• /
• v.24 no.6
• /
• pp.38-49
• /
• 1997

0.4mm Resign Rule의 Super Low Power Dissipation, Low Voltage. Operation-5- Full CMOS SRAM Cell을 개발하였다. Retrograde Well과 PSL(Poly Spacer LOCOS) Isolation 공정을 사용하여 1.76mm의 n+/p+ Isolation을 구현하였으며 Ti/TiN Local Interconnection을 사용하여 Polycide수준의 Rs와 작은 Contact저항을 확보하였다. p-well내의 Boron이 Field oxide에 침적되어 n+/n-well Isolation이 취약해짐을 Simulation을 통해 확인할 수 있었으며, 기생 Lateral NPN Bipolar Transistor의 Latch Up 특성이 취약해 지는 n+/n-wellslze는 0.57mm이고, 기생 Vertical PNP Bipolar Transistor는 p+/p-well size 0.52mm까지 안정적인 Current Gain을 유지함을 알 수 있었다. Ti/TiN Local Interconnection의 Rs를 Polycide 수준으로 낮추는 것은 TiN deco시 Power를 증가시키고 Pressure를 감소시킴으로써 실현할 수 있었다. Static Noise Margin분석을 통해 Vcc 0.6V에서도 Cell의 동작 Margin이 있음을 확인할 수 있었으며, Load Device의 큰 전류로 Soft Error를 개선할수 있었다. 본 공정으로 제조한 1M Full CMOS SRAM에서 Low Vcc margin 1.0V, Stand-by current 1mA이하(Vcc=3.7V, 85℃기준) 를 얻을 수 있었다.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.24 no.4
• /
• pp.157-167
• /
• 2020

In this study, a field bridge test was conducted to find the dynamic properties of cable supported bridges with resilient-friction base isolation systems (R-FBI). Various ambient vibration tests were performed to estimate dynamic properties of a test bridge using trucks in a non-transportation state before opening of the bridge and by ordinary traffic loadings about one year later after opening of the bridge. The dynamic properties found from the results of the tests were compared with an analysis model. From the result of the ambient vibration tests of the cable supported bridge with R-FBI, it was confirmed that the dynamic properties were sensitive to the stiffness of the R-FBI in the bridge, and the seismic analysis model of the test bridge using the effective stiffness of the R-FBI was insufficient for reflecting the dynamic behavior of the bridge. In the case of cable supported bridges, the seismic design must follow the "Korean Highway Bridge Design Code (Limit State Design) for Cable supported bridges." Therefore, in order to reflect the actual behavior characteristics of the R-FBI installed on cable-supported bridges, an improved seismic design procedure should be proposed.

• Proceedings of the KSME Conference
• /
• 2003.11a
• /
• pp.402-407
• /
• 2003

The main reason to select the maxium plant efficiency through the performance test in fossil power plant is to increase the efficiency of power plant as well as saving energy collated with the policy of government. This study is aimed at unerstanding the variantion trend of efficiency and analyzing the efficiency of boiler and turbine through each of the performance test. Ultimately, the maxium efficiency of power plant will be presented in super-critical pressure type power plant.

• Earthquakes and Structures
• /
• v.6 no.1
• /
• pp.111-125
• /
• 2014

Multiple level performance of seismically isolated elevated storage tank isolated with multi-phase friction pendulum bearing is investigated under totally 60 records developed for multiple level seismic hazard analysis (SLE, DBE and MCE). Mathematical formulations involving complex time history analysis have been proposed for analysis of typical storage tank by multi-phase friction pendulum bearing. Multi-phase friction pendulum bearing represent a new generation of adaptive friction isolation system to control super-structure demand in different hazard levels. This isolator incorporates four concave surfaces and three independent pendulum mechanisms. Pendulum stages can be set to address specific response criteria for moderate, severe and very severe events. The advantages of a Triple Pendulum Bearing for seismic isolation of elevated storage tanks are explored. To study seismic performance of isolated elevated storage tank with multi-phase friction pendulum, analytical simulations were performed with different friction coefficients, pendulum radii and slider displacement capacities.

• Earthquakes and Structures
• /
• v.16 no.4
• /
• pp.401-413
• /
• 2019

The concept of base isolation for equipment is well known. Its application in buildings and structures is rather challenging. Introduction of horizontal flexibility at the base helps in proper energy dissipation at the base level thus reducing the seismic demand of the super structure to be considered during design. The present study shows the results of a series of numerical simulation studies on seismic responses of secondary system (SS) housed in non-isolated and base-isolated primary structures (PS) including equipment-structure interactions. For this study the primary structure consists of two similar single bay three-store reinforced cement concrete (RCC) Frame building, one non-isolated with conventional foundation and another base isolated with Lead plug bearings (LPB) constructed at IIT Guwahati, while the secondary system is modeled as a steel frame. Time period of the base isolated building is higher than the fixed building. Due to the presence of isolator, Acceleration response is significantly reduced in both (X and Y) direction of Building. It have been found that when compared to fixed base building, the base isolated building gives better performance in high seismic prone areas.