Stress Analysis in the Elastic-Plastic Analysis of Railway Wheels

Roya Sadat Ashofteh,Ali Mohammadnia 한국철도학회 2014 International Journal of Railway Vol.7 No.1

Fatigue and wear in wheels is often due to the forces and loading. These certainly have fundamental effects on reducing the wheel life and increasing the costs related to repairing and maintenance. Modeling and stress analysis of a wheel sample existing in the Iranian fleet have been performed in its contact with U33 and UIC60 rails. The results have been reviewed and analyzed in elastic and elastic-plastic phase and under static (railcar weight) and quasi static loads. Moreover, effects of wheel diameter, axle load, wheel material, rail type are analyzed.

Stress Analysis in the Elastic-Plastic Analysis of Railway Wheels

Ashofteh, Roya Sadat,Mohammadnia, Ali The Korean Society for Railway 2014 International Journal of Railway Vol.7 No.1

Fatigue and wear in wheels is often due to the forces and loading. These certainly have fundamental effects on reducing the wheel life and increasing the costs related to repairing and maintenance. Modeling and stress analysis of a wheel sample existing in the Iranian fleet have been performed in its contact with U33 and UIC60 rails. The results have been reviewed and analyzed in elastic and elastic-plastic phase and under static (railcar weight) and quasi static loads. Moreover, effects of wheel diameter, axle load, wheel material, rail type are analyzed.

Traditional, Multiple-intelligence Based Instruction, and L2 Pragmatics Development

Sajjad Gharibeh Gharibeh,Zhila Mohammadnia,Mehdi Sarkhosh 아시아테플 2022 The Journal of Asia TEFL Vol.19 No.2

Although a growing line of research has targeted the efficacy of multiple intelligence-based instructions on learners’ language learning and oral communication skills, studies exploring and incorporating the effects of multiple intelligence-based instructions on second language pragmatics development in general and politeness markers, in particular, are rare. The current study attempted to investigate the relative effect of multiple intelligence-based instructions on the politeness markers development. To this aim, thirty intermediate EFL learners studying New Interchange series in language institutes in Tabriz, Iran with the age range 13-17 were employed. McKenzie’s multiple intelligences questionnaires were conducted to pinpoint the participants’ dominant intelligences. Thus, the participants were assigned to two multiple-intelligence based experimental groups (A and B) and a control group. The results of two-way repeated-measures ANOVA (time × group) revealed that the participants in the experimental groups outperformed those in the control group in both comprehension/production posttests and delayed posttests, while there was not any significant difference between the experimental groups in the two testing occasions. Therefore, it can be concluded that adopting teaching methods and materials consistent with learners’ MIs would conspicuously enhance pragmatic competence.

Three dimensional finite element analysis of 4 inch smart flange on offshore pipeline

Moghaddam, Ali Shaghaghi,Mohammadnia, Saeid Techno-Press 2014 Ocean systems engineering Vol.4 No.4

Smart flanges are used for pipeline and riser repair in subsea. In a typical case in the gas export pipeline project, the end cap bolts of a 4inch smart flange were broken during operation, and in turn leakage occurred. This work presents the detail of three dimensional finite element analysis of the smart flange to support the observed end cap bolts failure. From finite element analysis it turns out that in the presence of external bending moment, an uneven contact distribution is present between seal and end cap, which in turn changes the uniform load distribution on bolts and threaten the integrity of bolts. On the other hand, 3D finite element analysis of interaction between pipeline and seabed is presented by means of Abaqus to explore the distribution of bending moment along the pipeline route. It is found that lateral buckling occurs in the pipeline which introduces large bending moment.

Analysis of offshore pipeline laid on 3D seabed configuration by Abaqus

Moghaddam, Ali Shaghaghi,Mohammadnia, Saeid,Sagharichiha, Mohammad Techno-Press 2015 Ocean systems engineering Vol.5 No.1

Three dimensional (3D) non-linear finite element analysis of offshore pipeline is investigated in this work with the help of general purpose software Abaqus. The general algorithm for the finite element approach is introduced. The 3D seabed mesh, limited to a corridor along the pipeline, is extracted from survey data via Fledermous software. Moreover soil bearing capacity and coefficient of frictions, obtained from the field survey report, and are introduced into the finite element model through the interaction module. For a case of study, a 32inch pipeline with API 5L X65 material grade subjected to high pressure and high temperature loading is investigated in more details.

Development of an electrochemical fentanyl nanosensor based on MWCNT-HA/ Cu-H3BTC nanocomposite

Maryam Akbari,Maryam Saleh Mohammadnia,Masoumeh Ghalkhani,Mohammad Aghaei,Esmail Sohouli,Mehdi Rahimi-Nasrabadi,Mohsen Arbabi,Hamid Reza Banafshe,Ali Sobhani-Nasab 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.114 No.-

Fentanyl is a potent narcotic drug with the same effects as morphine or heroin, but it’s significantly morepotent than these drugs. That means a tiny dose can have a dangerous impact and is also lethal, so it isessential to measure it. In this work, we have developed a new electrochemical sensor to measure thisdeadly drug utilizing a nanocomposite of multi-walled carbon nanotube, hydroxyapatite, and copperbasedmetal–organic framework (MWCNT-HA/Cu-H3BTC). The nanocomposite was first examined byX-ray diffraction, field emission scanning electron, Infrared, and Raman spectroscopic techniques. Theglassy carbon electrode (GCE) modified with MWCNT-HA/Cu-H3BTC was employed to determine fentanylin aqueous solutions. The highest oxidation current was generated for fentanyl at GCE/MWCNT-HA/Cu-H3BTC compared to the GCE, GCE/MWCNT, GCE/MWCNT/HA, and GCE/Cu-H3BTC. The GCE/MWCNT-HA/Cu-H3BTC showed a linear relationship between the concentration and the oxidation current of fentanylin the 0.01 to 100 lM with a detection limit of 3 nM. Finally, the fentanyl quantification in blood serumsamples was successfully performed. The GCE/MWCNT-HA/Cu-H3BTC’s reproducibility and stability wereindeed excellent.

Overexpression of miR-146a and miR-155 are Potentially Biomarkers and Predict Unfavorable Relationship between Gastric Cancer and Helicobacter pylori Infection

Masoud Karimi,Abdolreza Mohammadnia,Mohammad Amin Amini,Azar Ghavimi Shamekh,Elahe Derakhshanfar,Farzaneh Hosseini 전남대학교 의과학연구소 2023 전남의대학술지 Vol.59 No.3

Gastric Cancer (GC) is one of the most dangerous malignancies in the world. This study aims to evaluate the relationship between miR-146a and miR-155 in patients with H. pylori infections with GC compared to H. pylori-infected patients and healthy subjects. Forty patients with H. pylori and GC positive diagnoses and 40 patients with H. pylori positive and GC negative diagnoses, and 40 healthy persons were selected. The expression of miR-146a and miR-155 genes in the whole blood was examined using qRT-PCR. Moreover, ROC curves were drawn to represent the sensitivity and specificity of miR-146a and miR-155 expression as biomarkers. The results showed the expression of miR-146a and miR-155 in the whole blood of patients with H. pylori and GC positive diagnoses are significantly higher than in healthy individuals and are non-significantly enhanced compared to H. pylori positive and GC negative. Also, the results stated miR-146a and miR-155 expression in the whole blood of patients who are H. pylori positive and GC negative are significantly increased compared to healthy individuals. Furthermore, the ROC curve analysis of miR-146a and miR-155 RNA level demonstrated the two miRNAs have an appropriate sensitivity and specificity for diagnostic goals. In conclusion, H. pylori infection may increase the expression of miR-146a and miR-155 in patients with H. pylori and GC positive diagnoses, which can be effective in the curbing the progression of GC. For this reason, up-regulation of miR-146a and miR-155 along with H. pylori infection might contribute to the pathogenesis of GC, and also can be suggested as biomarkers for GC diagnosis and treatment.