en jalali 1400 2 1 gregorian 2021 5 1 16 Summer and Fall 2021 online 1 fulltext

en Offshore oil and gas extraction structures at shallow waters are conventionally supported by long driven steel pipe piles. In recent years, the direct CPT- or CPTu-based pile design methods have broadly been used to predict the bearing capacity of offshore piles in a more reliable manner. On the other hand, previous investigations have shown that the pile capacity is time-dependent (set-up and relaxation phenomena). However, time effects are missing in most CPT- or CPTu-based prediction methods. The main objective of this paper is to estimate the axial compressive bearing capacity of the offshore steel pipe piles driven in the marine clay deposits of the Persian Gulf based on some popular CPT/CPTu as well as static -based prediction methods. The estimated results are compared with the measured capacities obtained from the Pile Dynamic Analyzer (PDA) and the Case Pile Wave Analysis Program (CAPWAP). The measured values have been recorded at End-Of-Drive (EOD) and Beginning-Of-Restrike (BOR) conditions periodically up to nine months after pile installation. Then, the most reliable bearing capacity prediction methods are determined based on the shaft, base, and ultimate capacity values in short, medium, and long-term conditions. Here, five open-ended long steel pipe piles driven into very soft to hard marine clays of the Persian Gulf, Iran are considered to verify and evaluate the prediction quality of each method. It is shown that the ratio of predicted to measured ultimate bearing capacities obtained from the static analysis methods averagely have around 64% more scattering than the corresponding values obtained from the CPT and CPTu-based methods. The results of the current investigation can be employed in offshore piling projects of the Persian Gulf in which the time constraints of installation do not allow running dynamic load tests at different time intervals. Offshore pile,Bearing capacity,CPTu,PDA test,Time function,Set-up 1 12 http://ijmt.ir/browse.php?a_code=A-10-1556-1&slc_lang=en&sid=1 2021/06/22 1400/4/1 2022/01/2 1400/10/12 Amir Hossein Shamshirgaran Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University shamshirgaran.amir@gmail.com 0031947532846004022 0031947532846004022 No Babak Ebrahimian Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University b_ebrahimian@sbu.ac.ir 0031947532846004023 0031947532846004023 Yes

en The efficiency of ports and container terminals is strongly related to the process of loading containers onto and unloading containers from the docked ships. In this research, an issue of integrated equipment management in automated container terminals with the aim of increasing efficiency has been studied. Due to this issue falls into NP-Hard problems, it was divided into two sub-problems: Allocating resources to containers and arranging the containers serviced by automated guided vehicles. Both sub-problems were formulated and expressed using the linear integer-programming model. The first sub-problem is solved by the allocation of random process resources with uniform distribution and the second part is solved using a Sorting Genetic Algorithm. The main parameters of the proposed solution methods were determined with Minitab software and Taguchi techniques. In order to evaluate the efficiency and effectiveness of the proposed solution methods, many numerical experiments have been examined and evaluated. The experimental results show that the proposed solutions are efficient for estimating the service time and the number of automated guided vehicles required to transporting the containers in the container ports. Automated Container Terminal,Automated Guided Vehicle,Quay,Crane,Yard Crane 13 27 http://ijmt.ir/browse.php?a_code=A-10-961-2&slc_lang=en&sid=1 2021/06/222021/09/9 1400/6/18 2022/01/22022/02/8 1400/11/19 Hassan Rashidi Faculty of Statistics, Mathematics and Computer Science, Allameh Tabataba’i University hrashi@gmail.com 0031947532846003812 0031947532846003812 Yes Fatemeh Habibi Ehsaee Faculty of Statistics, Mathematics and Computer Science, Allameh Tabataba’i University f.habibi.ehsaparandni@gmail.com 0031947532846003813 0031947532846003813 No Fereshteh Azadi Parand Faculty of Statistics, Mathematics and Computer Science, Allameh Tabataba’i University f.a.parand@gmail.com 0031947532846003814 0031947532846003814 No

en The jacket structure is the key facility for the exploitation of marine resources. Offshore oil platforms located in an earthquake zone need to be analyzed for the structural response. A real offshore structure is always intricate and has to be idealized to diverse degree to fit in to the framework of the mathematical model for dynamic analysis. This work addresses the need for such a facilitated structural computation model. The planned scheme is based on laboratory work for improving the facilitated model. This study describes the scheme in employing the MDC associated with the GA method to create and update the facilitated structural model for analyzing the responses of a jacket platform. The facilitated modelling is first calculated based on MDC method, and then the platform model is refined and improved based on recorded modal features. Considering the presented model, the expense of analysis of jacket offshore structures is considerably reduced without incurring any loss of precision. Therefore, improvement of such approaches would be acutely beneficial to spread out technologies that can be applied for jacket structures with saving of both time and cost. Jacket offshore platform,,Vibration experiment,,Mixed-dimensional coupling (MDC),Model updating,,Genetic Algorithm (GA) 29 40 http://ijmt.ir/browse.php?a_code=A-10-1589-1&slc_lang=en&sid=1 2021/06/222021/09/92021/08/18 1400/5/27 2022/01/22022/02/82022/02/16 1400/11/27 Farhad Hosseinlou Faculty of civil engineering and architecture, Shahid Chamran University of Ahvaz F.hosseinlou@scu.ac.ir 0031947532846003816 0031947532846003816 Yes Najmeh Karami Department of Civil Engineering, University of Qom Najmeh.karami73@gmail.com 0031947532846003817 0031947532846003817 No Ehsan Dehghani Firoozabadi Department of Civil Engineering, University of Qom Dehghani@qom.ac.ir 0031947532846003818 0031947532846003818 No Ehsan Jeddi Faculty of civil engineering and architecture, Shahid Chamran University of Ahvaz e-jedi@stu-scu.ac.ir 0031947532846003819 0031947532846003819 No

en Oil, gas, and petrochemical facilities are strategic industry facilities, and their passive defense issues are of high priority in every country. Explosions due to sabotage or‌‌ aerial bombardments are of the most important factors in considering issues related to passive defense in the abovementioned facilities. In this study, the effect of blast loading on pressure vessels is investigated. The research issue is the study on the interaction between factors that affect on responses of pressure vessels under blast loading. For this purpose, the response surface method and central composite method were used for design numerical tests. Four factors were selected, type of pressure vessel (vertical or horizontal), the thickness of vessel body, the yield strength of steel vessel, and the amount of explosive material. Two responses were studied, the maximum displacement of pressure vessels and the residual displacement of pressure vessels. The result shows that the quadratic equation is the best model to provide equations. Then for two responses according to the four factors presented equations. These equations are simple and practical for engineers and researchers. The result shows that for both of the selected responses, in the stronger explosion, the role of body thickness and type of steel is the same but in the weaker explosion, the role of yield strength increased. In addition, it was found that role of the amount of explosive material is more than another parameter. And the interaction of material explosive by other parameters in vertical type is more than horizontal pressure vessels. ,Pressure Vessel,Oil and Gas Facilities,HE Explosion,RMS method,Passive Defense 41 52 http://ijmt.ir/browse.php?a_code=A-10-1757-1&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/15 1400/9/24 2022/01/22022/02/82022/02/162022/04/9 1401/1/20 Hamed Khalilpour University of Qom University s.hamed.khalilpour@gmail.com 0031947532846003865 0031947532846003865 No Ruhollah Amirabadi University of Qom University r.amirabadi@qom.ac.ir 0031947532846003866 0031947532846003866 Yes Mahdi Adjami Shahrood University of Technology adjami@shahroodut.ac.ir 0031947532846003867 0031947532846003867 No

en A clear understanding of marine traffic complexity is vital for safe and efficient navigation inside ports (e.g., pilotage inside the basin). Built on statistical analysis of vessels’ speed and course over ground extracted from satellite-based Automatic Identification System (AIS) data, an index of maritime traffic situation is developed in this research. After zoning the port basin, this index is calculated at each zone based on a combination of statistical measures (e.g., mean and standard deviation of speed and course over ground), in which vessels’ class based on their size and targeted pier is also incorporated. The model could effectively increase the situational awareness by simple monitoring of navigation activities and reflecting improvements. This becomes possible by identification of high opportunity and high risk zones, i.e., those with high index value which call for operation modification which are far from and close to the infrastructures (e.g., breakwaters), respectively. To explore the model outcome, it is typically applied on the Rajaee port - the largest port of Iran located in the Persian Gulf - and output are discussed with port’s maritime operators to analyze results. This resulted in identification of challenging zones for which pilotage plans could be improved. Also, it provided insight for better implementation of the basin which also could be considered in future development plans of the port. Traffic randomness,Situational awareness,AIS data,port performance problems,safety 53 61 http://ijmt.ir/browse.php?a_code=A-10-1349-1&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/152021/11/26 1400/9/5 2022/01/22022/02/82022/02/162022/04/92022/04/9 1401/1/20 Qadir Allahmoradi Tarbiat Modares University qallahmoradi@gmail.com 0031947532846003832 0031947532846003832 Yes Roozbeh Panahi University of Manitoba roozbeh_panahi@yahoo.com 0031947532846003833 0031947532846003833 No Reza Edraki Tarbiat Modares University reza.edraki@yahoo.com 0031947532846003834 0031947532846003834 No Hassan Akbari Tarbiat Modares University akbari.h@modares.ac.ir 0031947532846003835 0031947532846003835 No

en According to the important rule of maritime transport in world trade and prevent the further emission of greenhouse gases, ships' propulsion system needs innovative designs. One of these plans was the rotor sail introduced in recent decades. This idea uses wind power to help propulsion ships and is based on the Magnus effect, which Anton Flettner proposed. The selected geometry is based on the experimental tests performed at Reynolds number 5800 for speed ratio 0 and 4 simulated. The numerical solution has been done by the CFD method, and the results of lift and drag coefficients are obtained and validated. The results show that by changing the body form, the behavior of fluid around it also changes and leads to a different distribution of velocity and pressure. For both models with a stationary cylinder, CD=0.67 and for the first rotational model, CL=6.35 & CD=1.076 and for the proposed form, CL=6.041 & CD=1.039.  Rotor sail,Magnus effect,Flettner,Numerical analysis,Wind assisted ship propulsion 63 71 http://ijmt.ir/browse.php?a_code=A-10-1728-1&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/152021/11/262021/11/5 1400/8/14 2022/01/22022/02/82022/02/162022/04/92022/04/92022/04/14 1401/1/25 Amir Hossein Gharagozloo Chabahar Maritime University Ah_gharagozloo@yahoo.com 0031947532846004017 0031947532846004017 No Mohammad Reza Negahdari Chabahar Maritime University m.r.negahdari@gmail.com 0031947532846004018 0031947532846004018 Yes Abouzar Ebrahimi Chabahar Maritime University ab_ebrahimi@yahoo.com 0031947532846004019 0031947532846004019 No

en XBeach is designed to model nearshore area in storm conditions and needs adjustments to be used for longer periods. One way to implement this model on a medium- or long-term time scale is to take the model through a calibration step. Selecting the right calibration factors amongst several parameters can be challenging. In this study, ten factors were selected based on the literature review to determine the extent and nature of their impact on the transformation of the sandy profiles of Zarabad fishery harbor in seven months (2006.02.20 to 2006.09.23). By 2DH modeling, the results are represented by two profiles from the study area. Six of the ten selected parameters had a significant effect on the behavior of the profiles, and the results of seven out of ten parameters showed a convergence point in their profiles. As a result of this study, it is possible to move more consciously and expedite the calibration process of further studies. Of course, changing the particle size, the beach slope, the modeling duration, and the energy level of the incoming waves in the area may lead to different results, which can lead to further studies. Sensitivity Analyzes,Sandy beach,Sedimentation,Bed level change,Process-based modeling 72 85 http://ijmt.ir/browse.php?a_code=A-10-251-3&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/152021/11/262021/11/52021/11/12 1400/8/21 2022/01/22022/02/82022/02/162022/04/92022/04/92022/04/142022/04/23 1401/2/3 Ali Shams Derakhshan Shahrood University of Technology ali_shdr@yahoo.com 0031947532846004020 0031947532846004020 No Mehdi Adjami Shahrood University of Technology adjami@shahroodut.ac.ir 0031947532846004021 0031947532846004021 Yes

en Baltic Dry Index (BDIY:IND) is daily reported by Baltic Exchange. The index is a benchmark for the prices of ship chartering contracts which is a proxy for the maritime economy however the calendar anomalies of BDIY:IND have not yet been researched. This article investigates the day of week effects on BDIY:IND returns from 2014-03 to 2020-03. In this study, GARCH models were used to investigate the calendar effect on stock returns, and the Bootstrapping GARCH Regression is used to obtain the results with higher reliability. Regarding the correlation of time-based observations, the standard Bootstrap method does not apply to time series data; thus, the Bootstrap procedure based on resampling of GARCH's regression model residues is used in the present study. Based on a bootstrapping asymmetric GJR-GARCH approach, the results indicate that the Monday returns are significantly positive, which is in contrast with the usual findings in stock markets. It means the parties involved in shipping markets can still use information analysis as means to obtain further returns. The monetary figures of ship chartering contracts involve quite a large sum of money depends on movement of Baltic Dry Index hence having a knowledge of its behavior is vital for making smarter decisions for investors, shipowners and shipbrokers. Baltic Dry Index,Bootstrap,Days of week effects,Asymmetric GARCH 87 92 http://ijmt.ir/browse.php?a_code=A-10-1785-1&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/152021/11/262021/11/52021/11/122022/02/5 1400/11/16 2022/01/22022/02/82022/02/162022/04/92022/04/92022/04/142022/04/232022/07/16 1401/4/25 Kasra Pourkermani Khorramshahr University of Marine Sciences and Technology pourkermani@kmsu.ac.ir 0031947532846003879 0031947532846003879 Yes

en The oscillating water column is one of the most applicable and commercialized wave energy converters. There are some analytical-based simplified approaches like the rigid piston model for analyzing such converters in which the dynamic motion's damping, inertia, and stiffness are respectively modeled with a resistor, inductor, and capacitor (an RLC circuit). The power resonant frequency of wave energy converters is computed by solving the motion equation via its equivalent RLC circuit model. The free decay test is the other simple method for determining the resonant frequency and has been investigated experimentally. However, a comprehensive study is required. In this investigation, first, the effect of parameters like pressure, flow rate, and their phase difference on power resonant frequency, capture factor, etc., are conceptually investigated. Then, the relation between resonant frequency and free decay test frequency is studied for different chamber sizes. The results indicate that the free decay test frequency is generally close to the power resonant frequency. Wave energy converter,oscillating water column,power resonant frequency,free decay test,phase difference,RLC circuit 93 105 http://ijmt.ir/browse.php?a_code=A-10-1184-1&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/152021/11/262021/11/52021/11/122022/02/52022/05/22 1401/3/1 2022/01/22022/02/82022/02/162022/04/92022/04/92022/04/142022/04/232022/07/162022/07/17 1401/4/26 Abuzar Abazari Chabahar Maritime University abuzarabazari@cmu.ac.ir 0031947532846003884 0031947532846003884 Yes Mohammad Reza Zareei Chabahar Maritime University mrzarei@cmu.ac.ir 0031947532846003885 0031947532846003885 No Saleheh Poursheikhali Chabahar Maritime University s.poursheikhali@cmu.ac.ir 0031947532846003886 0031947532846003886 No

en In the present article we report for the first-time satellite image dataset on the internal waves of the Persian Gulf. These data include more than 3000 satellite images from Landsat 7, Landsat 8, Santinel-1, Santinel-2 and ASTER across the Persian Gulf, in which more than 400 images were detected internal waves during 2000 - 2015. The Prewitt and Canny's edge detection algorithm have been used to show internal waves in the satellite images. Also, some characteristics of internal waves, such as propagation direction, crest length, wavelength, width of solitons, length and area of packets and the distance of two consecutive packets inferred from imagery. This dataset of satellite images provides the main information for the analysis of internal waves in the Persian Gulf, which have been recorded in all seasons and in suitable weather conditions. Persian Gulf,Internal Waves,Dataset,Satellite Imagery 107 110 http://ijmt.ir/browse.php?a_code=A-10-1749-1&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/152021/11/262021/11/52021/11/122022/02/52022/05/222022/04/24 1401/2/4 2022/01/22022/02/82022/02/162022/04/92022/04/92022/04/142022/04/232022/07/162022/07/172022/09/5 1401/6/14 Hossein Farjami Iranian National Institute for Oceanography and Atmospheric Science (INIOAS) hfarjami@gmail.com 0031947532846003897 0031947532846003897 Yes Sajad Andi Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University sajad.andi96@gmail.com 0031947532846003898 0031947532846003898 No

en The effects of critical microstructural features on the mechanical behavior of sandwich structures under bending loading are investigated using the finite element method (FEM). The sandwich structures are made of a thick foam core and two thin skins consisting of laminated composites. The numerical results are extracted in the presence of the skin/core delamination which is one of the major failure modes of sandwich structures. The microstructural features include different types of woven fabric (E-glass, Kevlar and carbon), fiber volume fraction, number and arrangement type of layers in the composite skins, thickness and material properties of core, fracture toughness of adhesive face and the debonding length. Also, the effect of addition of carbon nanotubes (CNTs) into the foam core on the flexural properties of sandwich panels is studied. Comparisons are made between the predictions of the FEM and experimental measurements for the sandwich beams involving the skin/core delamination. A reasonable agreement is observed between two sets of results. It is found that the increase of fiber volume fraction and number of layers leads to an enhancement in flexural stiffness and increase in the delamination threshold load. The flexural properties of sandwich structures can be improved by increasing the thickness and elastic modulus of core. The results indicate that using carbon fibers into the composite skin is an efficient way to postpone the delamination of the skin from the core. Adding the CNTs can significantly enhance the delamination threshold load. Sandwich Structure,Bending,Delamination,Microstructural Effect,Finite Element method 111 121 http://ijmt.ir/browse.php?a_code=A-10-432-1&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/152021/11/262021/11/52021/11/122022/02/52022/05/222022/04/242022/07/21 1401/4/30 2022/01/22022/02/82022/02/162022/04/92022/04/92022/04/142022/04/232022/07/162022/07/172022/09/52022/11/20 1401/8/29 Hamid Rezaei Faculty of Marine Technology, Amirkabir University of Technology hrezaei@aut.ac.ir 0031947532846003910 0031947532846003910 Yes Milad Noorabadi Faculty of Marine Technology, Amirkabir University of Technology miladn2158@gmail.com 0031947532846003911 0031947532846003911 No

en The aim of this paper is the numerical hydrodynamic, structure, and vibration analysis of a pump jet propulsion system that mounted the tail of the AUV. A home code based on the boundary element method coupled with XFOIL code is used to extract the initial pump jet geometry. Then computational fluid dynamics analysis of DTMB4119 benchmark propeller (for validation of numerical result) and desired pump jet propulsion system have carried out based on RANS method and realizable k-ɛ turbulence model. Pump jet geometry modification has been done so that in the maximum hydrodynamic efficiency, the maximum amount of rotor moment is neutralized by the stator moment. However, according to the obtained hydrodynamic results, the stator moment neutralizes 85% of the rotor moment in the best situation. The maximum accessible hydrodynamic efficiency of the designed pump jet propulsion is 83%. The structural analysis of the designed pump jet propulsion has been performed on the rotor, stator, hub, and duct. For structure and vibration analysis, the pressure distribution on the pump jet obtained from the CFD results is applied point by point. The pump jet is aluminum with a Young modulus of 70 GPa. Based on the obtained structural results, the rotor will not have a problem vibrating. Pump Jet Propulsion,Hydrodynamic,Structure,Vibration,CFD 123 134 http://ijmt.ir/browse.php?a_code=A-10-487-4&slc_lang=en&sid=1 2021/06/222021/09/92021/08/182021/12/152021/11/262021/11/52021/11/122022/02/52022/05/222022/04/242022/07/212022/08/12 1401/5/21 2022/01/22022/02/82022/02/162022/04/92022/04/92022/04/142022/04/232022/07/162022/07/172022/09/52022/11/202022/11/30 1401/9/9 Ehsan Yari Maleke Ashtar University of Technology ehsanyari11@gmail.com 0031947532846003912 0031947532846003912 Yes