• Interaction and multiscale mechanics
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• v.5 no.4
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• pp.317-345
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• 2012

Cable-stayed bridges are often used in modern bridge engineering for connecting two geographical points of long distance. A special load case to cable-stayed bridges is earthquake, which can produce horizontal as well as vertical movements on the pylons of the bridge. These movements may be transient in nature, i.e., only resulting in the transient vibration of the bridge, but causing no damage consequences. In some extreme cases, they may cause permanent subsidence on one or more pylons of the bridge. In this paper, the effect of pylons' subsidence on the dynamic deformations of the bridge and on the cables' strength is thoroughly studied. Conclusions useful to the design of cable-stayed bridges will be drawn from the numerical study.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.887-890
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• 2003

High Speed data transmission over a long length of cable is limited due to the limited bandwidth of a cable which introduces ISI(Inter Symbol Interference). In order to compensate for the loss and phase dispersion in the cable, a pulse shaping in a transmitter and a line equalizer in receiver can be used. This paper presents a low-power and small-ana analog adaptive pulse shaping circuit and line equalizer, The design was fabricated in a 0.25${\mu}{\textrm}{m}$ mixed-signal CMOS process. The proposed pulse shaping circuit and equalizer operate at 400Mb/s on 50m STP(Shielded Twisted Pair) cable. It consumes 28.5${\mu}{\textrm}{m}$ with a 2.5-V power supply and occupies only 0.098 $\textrm{mm}^2$.

• Progress in Superconductivity and Cryogenics
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• v.2 no.2
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• pp.32-36
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• 2000

In this study, we performed the long-term expansion planning for the conceptual design of HTS power cable in Seoul area. In Korea, underground power cable has been required gradually with increasing demand of electric power transmission density and low loss characteristics in the comparison with a conventional power cables, so we assumed that the HTS power cable is applied between the downtown area and the outskirts of the city for the large power transmission capacity. This paper is to show the effects of HTS power cables in Seoul based on the power system analysis.

• Tunnel and Underground Space
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• v.5 no.1
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• pp.70-76
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• 1995

Two types of deformations can occur on the cable during the monitoring of the rock displacement by the time domain reflectometry. One is the impedance model for tensile deformation, and the other is the capacitance model for the shear deformation. The former gives a response signal with a gradual change in the amplitude of the reflected voltage, meanwhile the latter produces a signal with a blunted spike. The resolution of the TDR can be improved to 0.125% using calibration crimps on the cable of 60 meters long. It is recommended that the diameter of the cable should be 18 mm at least in order to induce a better reflected pulse without any open-circuit. The actual TDR technique cannot characterize the type and the magnitude of rock displacement quantitatively. Systematic investigation of the TDR parameters, such as the exact of cable diameter, cable length, number of crimps, combination of shearing and extension, and environment of the TDR equipment, will be able to improve the resolution to 0.01 mm.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.809-810
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• 2006

Reduction of AC losses is very important for realizing HTS cable and it had been reported that the same layer current controlled by twisting pitch and direction could reduce the AC losses effectively. During the long-term development of HTS cables, the superconductor AC losses will need to be reduced to a level determined by the economics of each installation and the efficiency of the refrigeration. Theoretical models have been developed to predict the magnitude of the losses in cables composed of several layers of flat HTS tapes. This paper is manufactured mini-model HTS cable and voltage signal line to spiral shape. Mini-model HTS cable is composed of 13 HTS tape. We measured to critical current and AC loss and compared used lock-in-amp to cancel coil. This data is useful to HTS cable of DAPAS program.

• Journal of the Society of Naval Architects of Korea
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• v.32 no.2
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• pp.56-67
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• 1995

In this paper, a ship-cable-vehicle system's static configuration is shown obtained by solving cable nonlinear statics. Eigenfrequencies of the cable were calculated by the frequency domain analysis application of the linearized cable dynamic equations. Also extreme tensions in a slack-and-snapping long vertical cable were calculated by the clip-ping-off model.

• Structural Engineering and Mechanics
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• v.41 no.1
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• pp.139-155
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• 2012

Structural health monitoring systems are often installed on bridges to provide assessments of the need for structural maintenance and repair. Damage or deterioration may be detected by observation of changes in bridge characteristics evaluated from measured structural responses. However, construction materials such as concrete and steel cables exhibit certain time-dependent behaviour, which also results in changes in structural characteristics. If these are not accounted for properly, false alarms may arise. This paper proposes a systematic and efficient method to study the time-dependent effects on the dynamic properties of cable-stayed bridges. After establishing the finite element model of a cable-stayed bridge taking into account geometric nonlinearities and time-dependent behaviour, long-term time-dependent analysis is carried out by time integration. Then the dynamic properties of the bridge after a certain period can be obtained. The effects of time-dependent behaviour of construction materials on the dynamic properties of typical cable-stayed bridges are investigated in detail.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.565-580
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• 2006

Set in constant increase and period current of lively technical development of railroad use and construction of cable stayed bridge railway bridge, one of bridge form of most suitable that think side police officer and the material enemy of bridge that use long rail, is increasing laying stress on the foreign countries. Main tower fixing department of this cable stayed bridge is consisted of main tower flange that support bearing plate, bay ring plate bearing plate, support end rib and diaphragm etc, as stress transmission mechanic that tensility of cable socket into normal force of main tower, and is used this time. These structural elements is very complex the structure and direction of load delivered from socket specially calbe particularly be different, and need FEM analysis that use Thick Shell element for suitable arrangement of mutual stress flowing grasping and absence that follow hereupon because all of the each support plate angle that suport this differ.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.376-378
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• 2003

Since the first underground transmission line of Korea was installed between Danginri and Yongsan substations in 1974, the two types of underground transmission power cables, oil-filled and XLPE, have been applied for underground transmission lines. As the manufacturing technologies of XLPE cable have been improved and the simplicity of installation and maintenance has been focused on, the installations of XLPE cables have been largely increased since the mid 1990's. For the first time, in Korea, the 345kV XLPE cable was installed between Youngseo and Youngdeungpo substations in 2003, June. So, this paper introduces the project profile, the design of cable and its accessory, the cable system design, installation and site test.

• Journal of Korean Society of societal Security
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• v.1 no.3
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• pp.51-57
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• 2008

The long-term behaviors of prestressed concrete cable-stayed bridges are considerably influenced by the time dependant material characteristics such as creep and shrinkage. This study investigated the influences of the change of relative humidity by application of the CEB-FIP model and ACI model, which are generally used in the prediction of long-term behavior of concrete structures. In case of the moment of girder, CEB-FIP model predicted a bigger effect of relative humidity change than the ACI model. Furthermore, the effect was significant. Also, the long-term behaviors between these models were different each other even under the same material condition. Therefore, the prediction of the long-term behavior should be compensated after comparative analysis with the results of material tests of each construction site and between the different models.