• Journal of the Korean Society for Railway
• /
• v.3 no.1
• /
• pp.27-33
• /
• 2000

In this paper, numerically evaluated is the crashworthiness of the new design of the standard Korea Electric Multiple Unit Train(K-EMU)[developed by the Korea Railway Research Institute]. The 4-car consist of K-EMU is analyzed under collision conditions such as normal coupling, heavy shunting, light collision and heavy collision to collide against another stationary one at 5 kph, 10 kph, 25 kph and 32 kph, respectively. Energy absorbing capacity of its draftgear commercially available in the market and to be equipped in K-EMU is evaluated under each collision condition. Analytical results show that draftgear only is not enough to provide necessary energy absorbing capacity. It is therefore concluded that additional energy absorbers like mechanical fuses should be adopted to improve the crashworthiness of K-EMU.

• Proceedings of the KSR Conference
• /
• 2004.10a
• /
• pp.640-645
• /
• 2004

In this thesis, the impact analysis for the shunting procedure using the dynamic buffer characteristics of the coupler was developed. In this study, each car was modeled as one dimensional element by using the equivalent system. After the impact, the slip exists only between wheel and rail in the braked trainset. For this analysis the analysis code named the POTAS-MSM (Power Transmission Analysis Software Multi Slip Mechanism) which was developed for the numerical analysis of dynamic system is developed. The validation of this analysis was proven by comparing the numerical results with the results of world-famous S company which is located in Europe.

• Proceedings of the KSR Conference
• /
• 1998.05a
• /
• pp.393-400
• /
• 1998

In this study, the crash situations and general crash analysis methods of railway rolling stocks were explained. To calculate the applied load and the maximum stress in the carbody when two aluminum railway vehicles were shunted, the finite element models for the carbody and the coupling system were made. The characteristic curve of draft gear which had a function to reduce impact force was modeled by nonlinear bar elements and the carbody was modeled by shell elements. Two shunting speeds, 5km/h and 8km/h, were considered and the results were analyzed and compared with static analysis case. Also, the aluminum railway vehicle with 60km/h was crashed against rigid wall to examine the global behavior of the carbody.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.16 no.1
• /
• pp.67-71
• /
• 2016

Eisenmenger syndrome (ES) is characterized by pulmonary arterial hypertension and right-to-left shunting. The signs and symptoms of ES include cyanosis, shortness of breath, fatigue, hemoptysis, and sudden death. In patients with ES, it is important that the systemic and pulmonary circulations be properly distributed and maintained. General dental treatment is not known to be particularly dangerous. To control pain and anxiety, local anesthetics without epinephrine are usually recommended. However, in cases of difficulty of cooperation, general anesthesia for dental treatment makes the condition worse. In the present case, intravenous deep sedation with propofol and remifentanil was administered for behavioral management during dental treatment successfully.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2002.04a
• /
• pp.470-477
• /
• 2002

Possibility of passive piezoelectric damping based on a new shunting parameter estimation method is studied using finite element analysis. The adopted tuning method is based electrical impedance that is found at piezoelectric device and the optimal criterion for maximizing dissipated energy at the shunt circuit. Full three dimensional finite element model is used for piezoelectric devices with cantilever plate structure and shunt electronic circuit is taken into account in the model. Electrical impedance is calculated at the piezoelectric device, which represents the structural behavior in terms of electrical field, and equivalent electrical circuit parameters for the first mode are extracted using PRAP (Piezoelectric Resonance Analysis Program). After the shunt circuit is connected to the equivalent circuit for the first mode, the shunt parameters are optimally decided based on the maximizing dissipated energy criterion. Since this tuning method is based on electrical impedance calculated at piezoelectric device, multi-mode passive piezoelectric damping can be implemented for arbitrary shaped structures.

• Journal of Chest Surgery
• /
• v.27 no.8
• /
• pp.705-707
• /
• 1994

birth-weight infants during the recovery phase of respiratory distress syndrome and has been associated with long-term pulmonary sequelae. The importance of surgical and medical abolition of left-to-right shunting in symptomatic neonates is established. Four preterm infants with birth weights under 1, 500gm with a PDA unresponsive to pharmacological closure underwent ligation. Two of preterm infants survived to be discharged and are developing normally. One infant has died due to respiratory distress syndrome, septicemia and necrotizing enterocolitis during hospital stay and other infant died due to septicemia after hospital discharge with follow-up for 6 months.

• Journal of the Korea Safety Management & Science
• /
• v.17 no.3
• /
• pp.81-88
• /
• 2015

Infrastructure such as tracks, catenary, rolling stock and signaling systems, and close interface with the human factors of train drivers, shunting staff and maintenance staff are required for train operations. Safety management is the most essential part for the functioning of a train. In line with the safety management, each rail operator has a safety guidance system and the Ministry of Land, Infrastructure and Transport operates Railway Safety Inspector system. Safety Inspector System is to train employees working in the field to be aware of rules and regulations, and to improve identified risk factors. Hence, it is necessary to establish systematic training and inspection methods for safety guidance staff and make clear the roles and responsibilities of safety inspectors according to the Occupational Safety and Health Act, and safety instructors for several inspections according to the Railroad Safety Act.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.673-678
• /
• 2008

In crushed service areas of Metro railway lines, there are problems such as the buildup discontent, the irregular operation time and rotation of rolling stocks, caused by frequently occurred train delay. Train delay is affected by operation conditions or infrastructure capacities such as train schedule, line capacity, car rotation plan, shunting movements at origin and destination, and also by transport demand characteristics. Furthermore, a delay produce another delays and spread over the following trains. So it is not easy to build up a protection and recovery plan. In this research, we conduct experimental analysis study based on the real metro data, and as a result, present the relation between the traffic demand and the dwell time. And finally, propose future research themes for improving the operation efficiency of metro railways.

• Journal of Korean Neurosurgical Society
• /
• v.66 no.3
• /
• pp.281-288
• /
• 2023

While the standard management for posthemorrhagic hydrocephalus (PHH) has not been determined, many patients initially receive temporary treatment such as a ventricular drainage, a ventricular reservoir, or a ventriculosubgaleal shunt. Subsequently, approximately 15% of patients with PHH will require permanent cerebrospinal fluid diversion. Shunt placement is most commonly performed for PHH as permanent treatment. However, shunting still has high complication rates. Since the development of the neuroendoscopic technique has progressed, and indication has been expanded, endoscopic third ventriculostomy with or without choroid plexus cauterization has performed more frequently in recent years in patients with PHH. In this paper, the permanent treatment for PHH will be reviewed based on the latest evidence.

• Journal of Korean Neurosurgical Society
• /
• v.66 no.3
• /
• pp.274-280
• /
• 2023

Post-hemorrhagic hydrocephalus (PHH) in preterm infant is common, life-threatening and the main cause of bad developmental outcomes. Ventriculoperitoneal (VP) shunt is used as the ultimate treatment for PHH. Low birth weight and low gestational age are the combination of worse prognostic factors while the single most important prognostic factor of VP shunting is age. Aggressive and early intervention have better effect in intraventricular hemorrhage and intracranial pressures control. It reduces infection rate and brain damage resulted in delayed shunt insertion. It is extremely important to let PHH infants get older and gain weight to have internal organs to be matured before undergoing VP shunt. As premature infants undergo shunt after further growth, shunt-related complications would be reduced. So temporary surgical intervention is critical for PHH infants to have them enough time until permanently shunted.