The application of imperialist competitive algorithm for optimization of deposition rate in submerged arc welding process using TiO2 nano particle

Mohammad Reza Ghaderi,Masood Aghakhani,Amir Hossein Eslampanah,Kianoosh Ghaderi 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.1

We used a novel optimization algorithm based on the imperialist competitive algorithm (ICA) to optimize the deposition rate in thesubmerged arc welding (SAW) process. This algorithm offers some advantages such as simplicity, accuracy and time saving. Experimentswere conducted based on a five factor, five level rotatable central composite design (RCCD) to collect welding data for depositionrate as a function of welding current, arc voltage, contact tip to plate distance, welding speed and thickness of TiO2 nanoparticles coatedon the plates of mild steel. Furthermore, regression equation for deposition rate was obtained using least squares method. The regressionequation as the cost function was optimized using ICA. Ultimately, the levels of input variables to achieve maximum deposition ratewere obtained using ICA. Computational results indicate that the proposed algorithm is quite effective and powerful in optimizing thecost function.

New towns as deconcentration or another concentration in the metropolis: evidence from Parand New Town in the Tehran Metropolitan Area

Reza Kheyroddin,Mohammad Ghaderi 서울시립대학교 도시과학연구원 2020 도시과학국제저널 Vol.24 No.1

The development of Parand New Town continues with the purposes such as ‘attraction of Tehran's overflow population’. Reflecting on its expansion and communications with Tehran City strengthens the idea that the development of this new town is not consistent with its main goal. The present study aimed to describe the realities on residence and living in Parand New Town descriptively and analytically. First, available and reliable statistics and information were used to express how the concentration of population is in the Tehran Metropolitan Area using quantitative methods and Herfindahl index. Then, using field studies, a sample of 384 people were selected and the designed questionnaires were distributed among them to validate the analysis. The results indicate that the concentration of population in the Tehran Metropolitan Area has increased compared to the whole country (Iran), and over the past two decades, the population has been growing faster in the cities surrounding Tehran City. The same trend is also observed in Parand New Town. Moreover, the residents of Parand new town include direct and secondary immigrants entering Tehran Province and such a situation is not so much in line with the deconcentration of Tehran. Parand New Town is attracting the population from the areas outside the Tehran Conurbation, due to its some attractions such as cheap housing and its proximity to Tehran, which will result in an intensified concentration of the Tehran Metropolitan Area. Moreover, Parand New Town residents’ tendencies show that this new town will become an immigrant throwing platform to Tehran. Thus, there is a need for seeking other strategies to inhibit and adjust this situation.

Codification strategies for achieving spatial justice in Iran

Mostafa Ghaderi Hajat,Mohammad Reza Hfeznia 대한공간정보학회 2020 Spatial Information Research Vol.28 No.3

Spatial injustice is an important feature of spatial organization in Iran, which is formulated on a core-periphery structure from the local to national scale. The current research with use descriptive-analytic method intends to codify solutions to access spatial justice in Iran. The results showed that spatial injustice in Iran relates to its natural geography and unequal distribution of natural resources (inherent characteristics), the human geography and spatial structure of the nation, centralism in political system, methods of policy-making, national development planning, regional and global geopolitical environment, inequality in the distribution of political power, wealth and opportunity resources. According to the research, to access spatial justice, the following strategies have been suggested: optimal spatial distribution of wealth flow as a developmental prerequisite namely management of money flow in the country, allocation of a specific portion of provincial budgets for balanced development in order to achieve regional balance, strengthening of local potential to increase the efficiency of achieving balanced development, attention to the systemic thinking about spatial justice and planning at the local, regional and national levels, revision of the principles of the Constitution related to the centralization for spatial distribution of executive and political power in the country.

Predicting the combined effect of TiO2 nano-particles and welding input parameters on the hardness of melted zone in submerged arc welding by fuzzy logic

Masood Aghakhani,Mohammad Reza Ghaderi,Maziar Mahdipour Jalilian,Ali Ashraf Derakhshan 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.7

Submerged arc welding (SAW) is a high-quality arc welding process used in heavy industries for welding thick plates. In this process,selecting appropriate values for the input parameters is required for high productivity and cost effectiveness. A very important weld quality characteristic affected by welding input parameters is the hardness of melted zone (HMZ). This paper reports the applicability of fuzzy logic (FL) to predict HMZ in the SAW process which is affected by the combined effect of TiO2 nano-particles and welding input parameters. The arc voltage, welding current, welding speed, contact tip-to-plate distance, and TiO2 nano-particles were used as input parameters and HMZ as the response to develop FL model. A five-level five-factor central composite rotatable design (CCRD) was used in the experiments to generate experimental data. Experiments were performed, and HMZs were measured. The predicted results from FL were compared with the experimental data. The correlation factor value obtained was 99.99% between the measured and predicted values of HMZ. The results showed that FL is an accurate and reliable technique for predicting HMZ because of its low error rate.

3-D numerical evaluation of residual stress and deformation due welding process using simplified heat source models

Amir Hossein Eslampanah,Mohammad Ebrahim Aalami-aleagha,Saeid Feli,Mohammad Reza Ghaderi 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.1

Thermal elastic–plastic finite element method has been employed to predict residual stress and deformation in a T-Fillet welded joint. An uncoupled thermal–mechanical three-dimensional (3-D) model has been developed. A nonlinear-transient heat flow analysis wasused to obtain the temperature distribution; then by applying thermal results in the three dimensional elastic-plastic model, residual stressand deformation distribution were obtained. Experiments were carried out to find fusion zone dimensions and displacement. Two heatsource models with infinite speed are proposed and the mechanical result of the mentioned models and normal moving heat source arecompared.

Sedimentary copper mineralization in the upper red formation, Yakhab area, central Iran

Kaveh Pazand,Ali Behzadinasab,Mohammad Reza Ghaderi,Mohammad Reza Rezvanianzadeh 한국자원공학회 2019 Geosystem engineering Vol.22 No.6

Copper mineralization in the Yakhab area, Central Iran, appears as disseminated copper sulfides along a redox boundary in gray sandstone of Upper Red Formation (URF). The URF formation section was investigated in the study area and report copper mineralization. Geochemical analyses of the Yakhab deposits showed maximum of 7.5 wt. % copper, 1.6 wt. % molybdenum and 116 mg/kg silver in the gray sandstone. In Yakhab section URF exposer reaches a thickness of as much as 1400 m that often copper mineralization is found in Midsection (261-681 m) in the grey sandstone in the form of patches inside plant fossils. Based on X-Ray Diffraction (XRD) analyses, microscopic studies and field observation paratacamite, atacamite, covellite and chalcocite were identified as major copper minerals and Powellite is the major molybdenum mineral in URF sandstone. The main phase of the copper mineralization in the Yakhab area was developed during diagenesis.

Genistein Suppression of Matrix Metalloproteinase 2 (MMP-2) and Vascular Endothelial Growth Factor (VEGF) Expression in Mesenchymal Stem Cell Like Cells Isolated from High and Low Grade Gliomas

Yazdani, Yasaman,Rad, Mohammad Reza Sharifi,Taghipour, Mousa,Chenari, Nooshafarin,Ghaderi, Abbas,Razmkhah, Mahboobeh Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.12

Objective: Brain tumors cause great mortality and morbidity worldwide, and success rates with surgical treatment remain very low. Several recent studies have focused on introduction of novel effective medical therapeutic approaches. Genistein is a member of the isoflavonoid family which has proved to exert anticancer effects. Here we assessed the effects of genistein on the expression of MMP-2 and VEGF in low and high grade gliomas in vitro. Materials and Methods: High and low grade glioma tumor tissue samples were obtained from a total of 16 patients, washed with PBS, cut into small pieces, digested with collagenase type I and cultured in DMEM containing 10% FBS. When cells reached passage 3, they were exposed to genistein and MMP-2 and VEGF gene transcripts were determined by quantitative real time PCR (qRT-PCR). Results: Expression of MMP-2 demonstrated 580-fold reduction in expression in low grade glioma cells post treatment with genistein compared to untreated cells (P value= 0.05). In cells derived from high grade lesions, expression of MMP-2 was 2-fold lower than in controls (P value> 0.05). Genistein caused a 4.7-fold reduction in VEGF transcript in high grade glioma cells (P value> 0.05) but no effects were evident in low grade glioma cells. Conclusion. Based on the data of the present study, low grade glioma cells appear much more sensitive to genistein and this isoflavone might offer an appropriate therapeutic intervention in these patients. Further investigation of this possibility is clearly warranted.