scholarly journals Applying System Dynamics of Discrete Supported Track to Analyze the Rail Corrugation Causation on Curved Urban Railway Tracks

2021 ◽  
Vol 2021 ◽  
pp. 1-21
Author(s):  
Xianxian Yin ◽  
Xiukun Wei ◽  
Haichao Zheng
Keyword(s):  
Friction And Wear ◽  
Theory Model ◽  
Resonant Vibration ◽  
Superposition Model ◽  
Occurrence Probability ◽  
Superharmonic Resonance ◽  
Rail Corrugation ◽  
Urban Rail ◽  
Practical Model ◽  
The Impact

Urban rail corrugation on curved tracks with small radii causes strong howling during operation, which has been bothering subway operating companies for many years. Therefore, revealing its causes and growth is important for the comfort and safety of subway operation. Current studies believe that the occurrence of rail corrugation is largely due to the resonant vibration of the wheel-rail system. However, little attention has been paid to the key causes of the track resonance and the practical prediction of the occurrence probability of rail corrugation on the certain track. This paper intends to solve these above issues. Firstly, the practical model of predicting the rail corrugation growth is proposed based on the wheel-rail coupling interaction, the key causes of corrugation are investigated, and the sensitivity analysis is carried out, while the corrugation superposition model is introduced to the analyze the corrugation evolution as well as to validate the corrugation growth from the aspect of material friction and wear. Secondly, the impact of the key causes on the initiation and development of the rail corrugation is investigated based on the cosimulation. Finally, case studies validate the proposed theory model and method. The results show that the practical prediction model for the rail corrugation growth proposed in this paper is able to estimate the occurrence possibility of rail corrugation on a specific track, and the superharmonic resonance of the track directly excited by passing vehicles eventually leads to rail corrugation. It is also found that shortwave corrugation develops more rapidly, and adjusting the support stiffness or sleeper spacing leads to fluctuations in the corrugation wavelength and its wear rate.

scholarly journals Randomized Binomial Tree and Pricing of American-Style Options

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Hu Xiaoping ◽  
Cao Jie
Keyword(s):  
American Option ◽  
Option Prices ◽  
Occurrence Probability ◽  
Binomial Tree ◽  
No Arbitrage ◽  
Complete Market ◽  
Cubic Polynomial ◽  
American Style ◽  
The Impact ◽  
And Storage

Randomized binomial tree and methods for pricing American options were studied. Firstly, both the completeness and the no-arbitrage conditions in the randomized binomial tree market were proved. Secondly, the description of the node was given, and the cubic polynomial relationship between the number of nodes and the time steps was also obtained. Then, the characteristics of paths and storage structure of the randomized binomial tree were depicted. Then, the procedure and method for pricing American-style options were given in a random binomial tree market. Finally, a numerical example pricing the American option was illustrated, and the sensitivity analysis of parameter was carried out. The results show that the impact of the occurrence probability of the random binomial tree environment on American option prices is very significant. With the traditional complete market characteristics of random binary and a stronger ability to describe, at the same time, maintaining a computational feasibility, randomized binomial tree is a kind of promising method for pricing financial derivatives.

scholarly journals Preliminary examination of reliability and validity of the Japanese child anxiety impact scale-parent version in Japanese community sample

2021 ◽  
Author(s):  
Sho Okawa ◽  
Honami Arai ◽  
Hideki Nakamura ◽  
Yuko Urao ◽  
Tessa Reardon ◽  
...  
Keyword(s):  
Convergent Validity ◽  
Community Sample ◽  
Child Anxiety ◽  
Reliability And Validity ◽  
Japanese Version ◽  
Theory Model ◽  
Validity And Reliability ◽  
Impact Scale ◽  
The Impact ◽  
Parent Version

AbstractThe child anxiety impact scale-parent version (CAIS-P) is a useful measure to assess the impact of anxiety on a child’s daily life; however, a Japanese version of the CAIS-P has not been developed, and whether the CAIS-P can be utilized in Eastern countries remains unascertained. The purpose of this study was to develop a Japanese version of the CAIS-P and examine its reliability and validity. Parents of 400 children (aged 7 to 15 years) from the Japanese community completed the CAIS-P. A confirmatory factor analysis indicated that the factor structure of the original CAIS-P, consisting of school activity, social activity, and home/family activity factors, provided a good fit for the Japanese version of the CAIS-P. Estimated Spearman’s correlation coefficients showed moderate correlations between the total and factor scores of the CAIS-P, anxiety symptoms (Spence Child Anxiety Scale-parent version), and depressive symptoms (Child Depression Inventory). Furthermore, the item response theory model revealed that each factor of the CAIS-P is a high information reliable measure for children with high trait anxiety. These results provide support for the Japanese version of the CAIS-P’s factorial validity, convergent validity, and reliability and its potential for application in child anxiety research in Japan.

scholarly journals FDI INFLOW SPILLOVER EFFECT IMPLICATIONS ON THE ASIA PACIFIC PRODUCTIVITY GROWTH THROUGH THE EXPORT CHANNEL

2017 ◽  
Vol 26 (3) ◽  
pp. 57-72
Author(s):  
Rahim KIA LASHAKI ◽  
Elsadig Musa AHMED
Keyword(s):  
Spillover Effect ◽  
Physical Capital ◽  
Theory Model ◽  
Asia Pacific ◽  
Second Step ◽  
Growth Theory ◽  
Fdi Inflows ◽  
Catching Up ◽  
Productivity Indicators ◽  
The Impact

This paper inspects the influence of Foreign Direct Investment (FDI) inflows onthe catching up process developed by labour, physical capital, human capital, absorptivecapacity, telecommunications investment, and export channel on Asia Pacific's sustainableproductivity growth. A panel data from the period of 1970 to 2012 was used. The modifiedextensive growth theory model that is based on output approach was applied. Bothgrowth accounting and econometric approaches were considered to estimating theparameters of variables in first step and in the second step productivity indicators werecalculated. The results show that the FDI inflows and inputs used are input driven thatwas generally more predominant than total factor productivity (TFP) growth. Meanwhile,The GDP grew significantly during the periods of the study by development of humancapital, export, and telecommunications investment (input driven) variables, whichsupported by FDI inflows. Accordingly, the impact of export channel on the TFP growthfound to be positive with insignificant contribution in most the group selected countries.

Friction and wear behaviors of sand particle against casing steel

2018 ◽  
Vol 233 (3) ◽  
pp. 393-405
Author(s):  
Liu Yang ◽  
Deguo Wang ◽  
Yanbao Guo ◽  
Shuhai Liu
Keyword(s):  
Abrasive Wear ◽  
Friction And Wear ◽  
Oil And Gas ◽  
Wear Behavior ◽  
Processing Condition ◽  
Friction Model ◽  
Real Contact Area ◽  
Sand Particle ◽  
Friction Resistance ◽  
The Impact

Tools abrasive wear due to sand particles has caused severe damage during oil and gas exploitation. The friction and wear behaviors of single quartz sand particle against N80 casing steel were investigated to estimate the particle transport resistance and particle abrasive wear behavior using a homemade tribometer in wellbore sand cleanout. Various measurements were conducted to research the impact factor of particle under different water processing condition, dry, short immersion, wet, influences of load and slide velocity. Experimental results indicated that particle-casing friction resistance is mainly formed due to plowing and adhesion effect. Casing transfer and plowing removal are two main damage forms. Particle real contact area increases noticeably after water absorption, which decreases the hertz contact stress and finally produces less plowing depth of casing steel and causes less damage. With load increasing, friction resistance and wear increase with addition of plowing depth. A simple particle-casing friction model was established considering the experimental contact behavior.

Mechanism Analysis of the Impact on Chinese Urban Rail Transit Construction on the Surrounding Real Estate Prices

2012 ◽  
Vol 178-181 ◽  
pp. 1866-1869
Author(s):  
Jian Liang Lv ◽  
Ying Jiang
Keyword(s):  
Real Estate ◽  
Land Development ◽  
Value Added ◽  
Urban Rail Transit ◽  
Rail Transit ◽  
Mechanism Analysis ◽  
The Real Estate ◽  
Urban Rail ◽  
Real Estate Prices ◽  
The Impact

This paper first studies the real estate prices and and its effecting factors, and point out the construction of urban rail transit effects large on its surrounding real estate prices. Then, the paper clarifies the theoretical basis of its effects, and finally analyzes mechanism that construction of rail transit can make its surrounding real estate value-added. The urban rail transit construction can improve surrounding property accessibility, the residents travel convenient, increasing the intense of land development, changing nature of land use, adjusting industrial layout, accelerating expanded urbanized areas, raising employment opportunities, promoting socio-economic prosperity and development. It provides reference for the reasonable allocation of late-stage value-added benefits, and people can get a comprehensive and systematic understanding of the impact of urban rail transit construction and its surrounding real estate prices.

A Study of the Impact of Innovation on Industrial Upgrading in China: A Spatial Econometric Analysis Based on China’s Provincial Panel Data

2020 ◽  
Vol 24 (3) ◽  
pp. 272-281
Author(s):  
Jiao Jiang ◽  
Xindong Zhao ◽  
◽  
Keyword(s):  
Panel Data ◽  
Industrial Structure ◽  
Spillover Effect ◽  
Theory Model ◽  
Regional Innovation ◽  
Industrial Upgrading ◽  
Logical Connection ◽  
Depth Analysis ◽  
The Impact ◽  
Industrial Structure Upgrading

This study provides an in-depth analysis of the impact of innovation on industrial upgrading from theoretical and practical perspectives. In terms of theory, based on the endogenous growth theory model, a multi-sectoral growth model is constructed to portray the inherent logical connection between innovation and industrial structure upgrading. The results show that innovation has an important impact on industrial structure upgrading. Industrial structure upgrading depends on differences in innovation level among industries and the substitution relationship of finished products in the industry. From an empirical perspective, based on the panel data of 31 provinces in China from 2005 to 2017, the spatial effect of innovation on industrial upgrading was analyzed using the spatial Durbin model. The results show that innovation and industrial structure upgrading has significant spatial correlation effects, and regional innovation can drive China’s industrial upgrading. Meanwhile, the space spillover effect is an important factor that cannot be ignored in industrial upgrading.

The impact of governance development models on urban rail efficiency

2008 ◽  
Vol 42 (9) ◽  
pp. 1238-1250 ◽  
Author(s):  
Priyanka Jain ◽  
Sharon Cullinane ◽  
Kevin Cullinane
Keyword(s):  
Development Models ◽  
Urban Rail ◽  
The Impact
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