Adaptive green traffic signal controlling using vehicular communication

Shaghaghi, E.,Jabbarpour, M. R.,Md Noor, R.,Yeo, H.,Jung, J. J. Springer Science + Business Media 2017 Frontiers of information technology & electronic e Vol.18 No.3

Evidence Gap on the Prevalence of Non-conventional Risk Factors for Type 2 Diabetes in Iran

Abdolreza Shaghaghi,Ali Ahmadi 질병관리본부 2014 Osong Public Health and Research Persptectives Vol.5 No.5

Objectives: Robust scientific evidence exists about the role of non-conventional risk factors in type 2 diabetes worldwide. The current epidemiological pattern of the disease in Iran suggests a precipitating role for these non-conventional risk factors. This review was performed to examine the research evidence suggesting a higher prevalence of non-conventional type 2 diabetes risk factors in Iran. Methods: MeSH keywords were applied to search several databases, including PUBMED, MEDLINE, AMED, EMBASE, Iran DOC, and the Scientific Information Database without a time limit frominception to September 2011. The quality of the noninterventional and population-based studies on Iranians included in these databases was assessed by the authors and any disagreement was resolved with consensus. Results: The literature search yielded 1847 publications, of which 62 were included in this study after eliminating non-relevant and overlapping papers. No study was found that verified a higher prevalence of the non-conventional type 2 diabetes risk factors in the Iranian population. Conclusion: The identified evidence gap about the role of prominent nonconventional risk factors of type 2 diabetes in the Iranian population could be a major caveat in the application of an evidence-based approach to endorse or reject existing hypothesis about these risk factors. Studies on the prevalence of non-conventional biomarkers of type 2 diabetes among Iranians could be a promising area of research.

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.

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.

Intelligent Advisory Speed Limit Dedication in Highway Using VANET

Jalooli, Ali,Shaghaghi, Erfan,Jabbarpour, Mohammad Reza,Md Noor, Rafidah,Yeo, Hwasoo,Jung, Jason J. Hindawi Publishing Corporation 2014 The Scientific World Journal Vol.2014 No.-

<P>Variable speed limits (VSLs) as a mean for enhancing road traffic safety are studied for decades to modify the speed limit based on the prevailing road circumstances. In this study the pros and cons of VSL systems and their effects on traffic controlling efficiency are summarized. Despite the potential effectiveness of utilizing VSLs, we have witnessed that the effectiveness of this system is impacted by factors such as VSL control strategy used and the level of driver compliance. Hence, the proposed approach called Intelligent Advisory Speed Limit Dedication (IASLD) as the novel VSL control strategy which considers the driver compliance aims to improve the traffic flow and occupancy of vehicles in addition to amelioration of vehicle's travel times. The IASLD provides the advisory speed limit for each vehicle exclusively based on the vehicle's characteristics including the vehicle type, size, and safety capabilities as well as traffic and weather conditions. The proposed approach takes advantage of vehicular ad hoc network (VANET) to accelerate its performance, in the way that simulation results demonstrate the reduction of incident detection time up to 31.2% in comparison with traditional VSL strategy. The simulation results similarly indicate the improvement of traffic flow efficiency, occupancy, and travel time in different conditions.</P>

Experimental investigation on UHPC beams reinforced with GFRP and steel rebars and comparison with prediction equations

Parvin, Yousef Abbasi,Shaghaghi, Taleb Moradi,Pourbaba, Masoud,Mirrezaei, Seyyed Saeed,Zandi, Yousef Techno-Press 2022 Advances in concrete construction Vol.14 No.1

In this article, the flexural and shear capacity of ultra-high-performance fiber-reinforced concrete beams (UHPFRC) using two kinds of rebars, including GFRP and steel rebars, are experimentally investigated. For this purpose, six UHPFRC beams (250 × 300 × 1650 mm) with three reinforcement ratios (ρ) of 0.64, 1.05, and 1.45 were constructed using 2% steel fibers by volume. Half of the specimens were made of UHPFRC reinforced with GFRP rebars, while the other half were reinforced with conventional steel rebars. All specimens were tested to failure in four-point bending. Both the load-deformation at mid-span and the failure pattern were studied. The results showed that utilizing GFRP bars increases the flexural strength of UHPFRC beams in comparison to those made of steel bars, but at the same time, it reduces the post-cracking strain hardening. Furthermore, by increasing the percentage of longitudinal bars, both the post-cracking strain hardening and load-bearing capacity increase. Comparing the experiment results with some of the available equations and provisions cited in the valid design codes reveals that some of the equations to predict the flexural strength of UHPFRC beams reinforced with conventional steel and GFRP bars are reasonably conservative, while Khalil and Tayfur model is un-conservative. This issue makes it essential to modify the presented equations in this research for predicting the flexural strength of UHPFRC beams using GFRP bars.

Thermal effects on nonlocal vibrational characteristics of nanobeams with non-ideal boundary conditions

Farzad Ebrahimi,Gholam Reza Shaghaghi 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.18 No.6

In this manuscript, the small scale and thermal effects on vibration behavior of preloaded nanobeams with non-ideal boundary conditions are investigated. The boundary conditions are assumed to allow small deflections and moments and the concept of non-ideal boundary conditions is applied to the nonlocal beam problem. Governing equations are derived through Hamilton\' s principle and then are solved applying Lindstedt-Poincare technique to derive fundamental natural frequencies. The good agreement between the results of this research and those available in literature validated the presented approach. The influence of various parameters including nonlocal parameter, thermal effect, perturbation parameter, aspect ratio and pre-stress load on free vibration behavior of the nanobeams are discussed in details.

Dynamic characteristics of hygro-magneto-thermo-electrical nanobeam with non-ideal boundary conditions

Ebrahimi, Farzad,Kokaba, Mohammadreza,Shaghaghi, Gholamreza,Selvamani, Rajendran Techno-Press 2020 Advances in nano research Vol.8 No.2

This study presents the hygro-thermo-electromagnetic mechanical vibration attributes of elastically restrained piezoelectric nanobeam considering effects of beam surface for various elastic non-ideal boundary conditions. The nonlocal Eringen theory besides the surface effects containing surface stress, surface elasticity and surface density are employed to incorporate size-dependent effects in the whole of the model and the corresponding governing equations are derived using Hamilton principle. The natural frequencies are derived with the help of differential transformation method (DTM) as a semi-analytical-numerical method. Some validations are presented between differential transform method results and peer-reviewed literature to show the accuracy and the convergence of this method. Finally, the effects of spring constants, changing nonlocal parameter, imposed electric potential, temperature rise, magnetic potential and moisture concentration are explored. These results can be beneficial to design nanostructures in diverse environments.

Nonlocal buckling characteristics of heterogeneous plates subjected to various loadings

Ebrahimi, Farzad,Babaei, Ramin,Shaghaghi, Gholam Reza Techno-Press 2018 Advances in aircraft and spacecraft science Vol.5 No.5

In this manuscript, buckling response of the functionally graded material (FGM) nanoplate is investigated. Two opposite edges of nanoplate is under linear and nonlinear varying normal stresses. The small-scale effect is considered by Eringen's nonlocal theory. Governing equation are derived by nonlocal theory and Hamilton's principle. Navier's method is used to solve governing equation in simply boundary conditions. The obtained results exactly match the available results in the literature. The results of this research show the important role of nonlocal effect in buckling and stability behavior of nanoplates. In order to study the FG-index effect and different loading condition effects on buckling of rectangular nanoplate, Navier's method is applied and results are presented in various figures and tables.

Vibration analysis thermally affected viscoelastic nanosensors subjected to linear varying loads

Ebrahimi, Farzad,Babaei, Ramin,Shaghaghi, Gholam Reza Techno-Press 2018 Advances in nano research Vol.6 No.4

Unwanted vibration is an issue in many industrial systems, especially in nano-devices. There are many ways to compensate these unwanted vibrations based on the results of the past researches. Elastic medium and smart material etc. are effective methods to restrain unnecessary vibration. In this manuscript, dynamic analysis of viscoelastic nanosensor which is made of functionally graded (FGM) nanobeams is investigated. It is assumed that, the shaft is flexible. The system is modeled based on Timoshenko beam theory and also environmental condition, external linear varying loads and thermal loading effect are considered. The equations of motion are extracted by using energy method and Hamilton principle to describe the translational and shear deformation's behavior of the system. Governing equations of motion are extracted by supplementing Eringen's nonlocal theory. Finally vibration behavior of system especially the frequency of system is developed by implementation Semi-analytical differential transformed method (DTM). The results are validated in the researches that have been done in the past and shows good agreement with them.