• Proceedings of the KIEE Conference
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• 2004.04a
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• pp.287-289
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• 2004

Tilting train has been developed to increase the operational speed of the trains on conventional lines which have many curves. This train are tilted at curves to compensate for unbalanced carbody centrifugal acceleration to a greater extent than compensation produced by the track cant, so that passengers do not feel centrifugal acceleration and thus trains can run at higher speed at curves. This paper investigated train formation of TTX(tilting train express) with maximum operation speed 180 km/h.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.856-861
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• 1996

The occurrence of TTX in ciliated protozoa was investigated in order to clarify tetrodotoxin (TTX) accumulation mechanisms in marine organisms. Tissue culture bioassay, HPLC, and GC-MS analyses confirmed the occurrence of TTX in Euplotes mutabilis and also in bacteria isolated from the culture medium. Fluorescently labeled bacteria (FLB) were prepared with those bacteria, and predation by E. mutabilis was observed. The results indicated that TTX in bacteria can be transferred to higher trophic levels through the food chain.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.616-621
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• 2004

In this paper, the crush characteristics of a tilting train express (TTX) M-car design are evaluated with a head-on collision scenario. Its body shell is divided into three parts - front end, middle section, and rear end. For each part, crush-force relation is evaluated numerically through 3-dimensional shell element analysis with LS-DYNA. TTX's embody structure is a hybrid type structure made of steel and composite materials. Composite sandwich panels are modeled as layered shells whose layers have different material properties. And a damage material model is used to consider the effect of stiffness degradation during deformation. The crush characteristics obtained from these calculations will be used as material modeling data of full-rake collision analyses.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.462-467
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• 2004

In order to determine the most suitable material system which can achieve the lightweight design and fulfill the design requirements of carbody structures of Korean Tilting Train eXpress (TTX), aluminum carbody, composite carbody, and hybrid carbody combined with aluminum and composite structures were considered in present study. The finite-element analysis was used to verity the design requirements of the TTX carbody structures with the material system being considered in the design stages. The stresses in the carbody structures and deflections of underframe against static load cases were checked as design criteria. The results show that the hybrid carbody structures are beneficial with regard to weight savings and structural integrity when compared to aluminum and composite carbody structures.

• Journal of Life Science
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• v.10 no.2
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• pp.115-124
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• 2000

The present study was undertaken to separate the available components effectively, such as tetrodotoxin(TTX), docosahexaenoic acid(DHA, C22:6,ω-3) and eicosapentaenoic acid (EPA, C20:5,ω -3) from pufferfish liver waste, which are known to have high values as bioactive materials. By using ultrafiltration, it was possible to separate high contents of 68mg TTX from pufferfish liver waste. In contrast, by activated charcoal column, it was to obtain about 54mg TTX. The recovering ratios were 65.3% and 45.0% in the two different methods of ultrafiltration and activated charcoal column, respectively. From the results of HPLC and gas chromatography-mass spectrometry(GC-MS), the obtained toxins were identified to be TTX and its derivatives. In addition, it was also possible to obtain 72.3g DHA and 11.4g EPA from 1kg of pufferfish liver by high performance liquid chromatography (HPLC). These amounts of DHA and EPA were also 17.70% and 1.04% in the total lipid of pufferfish liver oil from analysis of gas chromatography(GC), respectively.

• The Korean Journal of Physiology
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• v.29 no.1
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• pp.103-111
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• 1995

Intracellular recordings were obtained from Purkinje cells in rat cerebellar slices maintained in vitro. Adding tetrodotoxin to the superfusion solution produced a typical pattern of repetitive burst firing consisting of a cluster of action potentials followed by a long hyperpolarization. TTX-induced oscillatory activity was not due to modulation of membrane potential although underlying mechanisms for maintenance of oscillatory activity were influenced by membrane voltage. The mechanism of TTX-induced oscillation was not related to the presence or amplitude of $I_h$ and could still induce the oscillatory activity after blockade of $I_h$ by cesium. The result from an experiment in which QX-314 was injected intracellularly strongly suggested that TTX-induced oscillatory firing activity was due to blockade of post-synaptic $Na^{+}$ currents intrinsic to PCs.

• Proceedings of the KSR Conference
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• 2006.05b
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• pp.1112-1117
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• 2006

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.540-545
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• 2007

The tilting train is able to tilt its body towards the center of the turning radius, preventing roll-over of the train as it runs on a curved rail at high-speed. This train, widely accepted for commercial purpose internationally, is very beneficial in that the operating time is shortened without much capital investment to the infrastructure where there are many curved rails. Over several years, the Korea Railroad Research Institute (KRRI) has developed such a train. In this paper, the safety of the Korean tilting train express (TTX) is investigated using a dynamic simulation model. Since proper safety standards have not been established for the TTX, those for the Korean train express (KTX) is employed to analyze the safety and ride comfort of the TTX. This study is useful in predicting the behavior of the TTX and ride comfort, and conforms that designed TTX is stable enough to satisfy the safety standards. It would be useful to recommend proper normal operating speed and determine the maximum safety speed, according to the result. Furthermore, it would be possible to provide basic reference data when analyzing the dynamic effect of the catenary system and the fatigue of the bogie.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.207-211
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• 2005

The Korean Tilting Train eXpress (TTX) with service speed of 180km/h have been developing using hybrid design concept combined with a sandwich composite structure for the carbody and stainless steel structure for the underframe to match the challenging demands with respect to cost efficient lightweight design for railway carriage structures. The sandwich composite structure was used to minimize the weight of the carbody, while the metal underframe was used to modify the design easily and to keep the strength of underframe for the installation of the electrical equipments. The sandwich composite structure was 23 meters long, 3 meters wide and 2.7 meters high, and cured as one body in a large autoclave equipment with the length of 30 meters and the diameter of 5 meters. The joint part between the carbody structure made of sandwich composites and the metal underframe was joined by the proposed design.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.679-684
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• 2004

Numerical analysis of aerodynamic characteristics was differently performed according to the running situation of the Korean Tilting Train eXpress (TTX) that would be introduced for an improvement in efficiency of the used railroad track. Fluent6.0 was used for the analysis of Non-tilting case, Tilting case and Passing-by case with the model of TTX. As a result, the aerodynamic drag had little difference between Tilting and Non-tilting case. However, pressure contour under the train of Tilting case was not symmetry because the gap between a train and the ground was different at both sides. And this disparity of pressure worked on the side force. In Passing-by case attraction and counterattraction occurred alternately and affected to the opposite train. When two trains were side by side, the maximum attraction was generated especially. Through an analysis of pressure wave in tunnel a large variation of pressure was generated by the bluff nose of TTX. The results in this study would be good data for the aerodynamic characteristic on TTX and provide important information to judgment of running safety.