• Journal of the Korea Institute of Military Science and Technology
• /
• v.11 no.2
• /
• pp.116-124
• /
• 2008

Current paper investigates the dynamic behavior and stability of an infrared search and track subjected to external disturbance having gimbal structure with three rotating axes keeping constant angular velocity in the azimuth direction. Euler-Lagrange equation is applied to derive the coupled nonlinear dynamic equation of motion of infrared search and track and the characteristics of dynamic coupling are investigated. Two equilibrium points with small variations from the nonlinear coupling system are derived and the specific condition from which a coupled equation can be three independent equations is derived. Finally, to examine the stability of system, Lyapunov direct method was used and system stability and stability boundaries are investigated.

• Proceedings of the KSR Conference
• /
• 2004.10a
• /
• pp.836-841
• /
• 2004

Recently, the development of the paved track is required as a Low-maintenance of conventional line. The main reason is that the line capacity and bearing of track are increased progressively. The most important factor of paved track is stability and applicability. To be based on this subject, Cement Mortar Pouring(CMP) paved track is developed. CMP paved track is a kind of ballast reinforced track using the pre packed concrete technique. The most important to design is characteristics of the structure. CMP slab's thickness is less than the conventional slab track and pouring layer is attached tie and roadbed directly. On this paper, to verify the basic structure of the CMP track, characteristics of the structure is investigated pouring layer, tie and interaction of the each layer using the 3D finite elment analysis.

• Journal of the Korean Society for Railway
• /
• v.9 no.2 s.33
• /
• pp.222-229
• /
• 2006

Recently, the development of the paved track is required as a low-maintenance of conventional line. The main reason is that the line capacity and bearing of track are increased progressively. The important factors of paved track are stability and applicability. To be based on this subject, Cement Mortar Pouring(CMP) paved track is developed. CMP paved track is a kind of ballast reinforced track using the prepacked concrete technique. The most important thing to design the paved track is to optimize the track structure considering various conditions. Because construction environment is very limited, cost is expensive and it has very complicated behavior. On this paper, structural characteristics of the paved track are investigated using the 3D finite element analysis to verify the optimized structure of the CMP track.

• Proceedings of the KSR Conference
• /
• 2004.06a
• /
• pp.974-979
• /
• 2004

Recently, the development of paved track is required as a Low-maintenance of conventional line. The most important factor of paved track is stability and applicability. In this method, the ballast is grouted with mortar so that the ballast can turn into a structure like slab. This method can be subdivided into the followings. One is the method with switching the ballast, and the other is without switching the ballast. The ordinary and actual states of the ballast and roadbed were investigated to evaluate the applicability of the paved track structure in this study, and various In-situ tests were applied. Non-destructive tests such as GPR, SASW, FWD were used, and bearing capacity of roadbed, depth of the ballast, and deterioration, penetration, and contamination of the ballast were focused. The result of this investigation was utilized in the selection of optimal paved track structure and data for preliminary design.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.1653-1661
• /
• 2008

A trial run of locally-developed tilting train has been in process on Chungbuk line since the test vehicle was first produced. For the system stabilization, interface verification among the systems including track, structure, catenary and signaling system, not to mention the rolling stock, is very crucial. In the area of wayside structure, the stability of track structure and train run shall be evaluated through the review of impact by increased speed by developed train on track structure. The study thus was intended to evaluate the impact on track while a tilting train is running the conventional line(ballast track), which is vulnerable to accelerated train speed. The evaluation of tilting train test running the part of Honam line was conducted to identify the impact on existing track performance by tilting train. To identify the performance of each part of track components while tilting train and high speed train were running the existing line, wheel load, rail bending stress, vertical displacement of rail and sleeper were compared so as to evaluate the expected impact by tilting train for improving the train speed.

• Proceedings of the KSR Conference
• /
• 2004.10a
• /
• pp.769-774
• /
• 2004

In this paper, the main factors affect on the longitudinal rail force are discussed. Considering rail-bridge interaction, analytical and experimental evaluation of track behavior has been achieved. It is concluded that the horizontal ballast strength, the expansion length of the bridge span, and the stiffness of the bridge sub-structure are the significant parameters affecting the stability of the continuous welded rail (CWR) track. And, it is suggested that the ballast resistance forces should be maintained to ensure the track stability during the service.

• Proceedings of the KSR Conference
• /
• 2004.10a
• /
• pp.781-787
• /
• 2004

Where the track is continuously welded over a bridge, the longitudinal force is interacted between the track and the sub-structure. Due to this respect, the expansion joint is used to decrease this force. But the expansion joint has several problems related to passenger comfort and maintenance etc. In this study, it is analysed about how the stability of the track is affected as the span length becomes longer in case of 2-span continuos bridge. It is found that there is no problem of an stability unless the span length is longer than 90m when the elastic shoe is used. And several parametric studies were also implemented.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1115-1120
• /
• 2007

Recently, the development of the paved track is required as a low-maintenance of conventional line. The main reason is that the line capacity and bearing of track are increased progressively. The important factors of paved track are stability and applicability. To be based on this subject, Cement Mortar Pouring(CMP) paved track is developed. CMP paved track is a kind of ballast reinforced track using the prepacked concrete technique. The most important thing to design the paved track is to optimize the track structure considering various conditions. In this study, the CMP track is constructed(30m) on a test line and the track performance tested by running train to evaluation the capability and workability. The track performance are tested to confirm the vibration acceleration of the car body, wheel and track, accumulated settlement, track irregularity and crack of surface.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.1036-1037
• /
• 2008

Test track of the Advanced EMU system will be developed and organically combined with technologies of power supply system, signal communication system and track structure. The purpose of the test track is a acquirement of reliability and stability through a sufficient performance test. Therefore, this paper draws up all management plans for tests of the Advanced EMU system.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.1689-1694
• /
• 2008

Recently, the development of the paved track is required as a low-maintenance of conventional line. The main reason is that the line capacity and bearing of track are increased progressively. The important factors of paved track are stability and applicability. To be based on this subject, cement mortar pouring type paved track is developed. The paved track is a kind of concrete track using the prepacked concrete technique. The most important thing to design the paved track is to optimize the track structure and materials considering various conditions. Until now, the paved track is verified a various material and structure test. In this paper, it is introduce to the test construction at the urban subway main line. The test construction is completed at Dec. 2007. A major object and substance is a guarantee of construction progress on main line, track performance, construction technique for curved section, transition zone and winter season, recycling the used ballast and application of specific sleeper for sharp curved section.