The reduced form models have been widely used in the literature to price the credit risk of defaultable assets. However, little has yet been done in using the reduced form model as a portfolio risk management tool. In this study, we propose a multi-firm reduced form model and use it to measure portfolio credit risk. We calibrate and back-test our model using corporate bond prices. Our results s...

The main topic of this article is the strength analysis selected bogie components – wheelset axle and frame. Axle calculations were based on analytical method conducted with different types materials. finite element was used for verification frame construction loads applied calculated according to PN-EN 13749 norm. a part suspended electric multiple unit which matter authors’ master thesis: „Th...

A combination of exponential and half logistic failure rate model for reliability studies is paid much attention. An attempt is made to present the distributional properties, estimation of parameters , testing of hypothesis and the power of likelihood ratio criterion about the proposed model .

The benefits of substituting the conventional solid wheelset by independently rotating wheels (IRW) in actively steered trailed railway vehicles have already been presented in many works. If a traction system is included in this kind of vehicle it will interact strongly with the active steering system. This paper investigates how traction and active steering systems can be combined in an IRW bo...

Salah satu suku cadang yang penting dalam kendaraan jenis tank adalah perangkat roda disebut bogie wheel. Boggie wheel merupakan bagian dari sistem terdiri track, arm, bracket dsb. Bogie terbuat material aluminium ditempa (forging). Saai ini proses pembuatan whell menggunakan baja dengan permesinan. Akibat pergantian tersebut maka bertambah bobotnya sebesar 4 ton. Hal berpengaruh pada manuver s...

The carbody shaking phenomenon (CSP) can greatly reduce the ride comfort of high-speed trains. To investigate abnormal vibration feature and causes CSP, extensive field measurements numerical simulations were conducted. A three-dimensional rigid-flexible coupled dynamic model a vehicle is constructed to reproduce CSP reveal key influence factors, in which finite element updated based on experim...