Ship collision is one of the most important marine casualties threatening safety of vessels, especially in the straits, waterways and coastal waters. Such an accident, in addition to its financial losses, is associated with severe environmental consequences. In order to prevent the collision among vessels, evaluation of near miss collision is crucial. Near miss ship collision indicates vessels in an encounter course where collision would happen if no maneuver was performed, or such a maneuver was not successful. In other words, the event that although it doesn’t cause injury or damage, but it has potential impact that be transformed into an accident and cause damage or injury. This paper, which uses vessels’ Automated Identification Sys

In this research, the structural behavior of a morning glory spillway has been evaluated when there is an unbalanced construction in the spillway crest. The unbalanced construction is defined as the ratio of vertical unbalance in construction to the diameter of the spillway crest. The spillway structure has been modeled using finite element method and the reservoir fluid has been simulated using finite volume method. The behavior of morning glory spillways with unbalanced crests has been investigated in two scenarios: (a) the crest without any anti-vortex structure, and (b) the crest with anti-vortex structures. Both scenarios have been simulated using dynamic linear analysis method. In addition, in each scenario, three amoun

Multi-peaked directional wave spectra have been estimated by the well-known maximum likelihood method and modeled by applying a numerical optimization approach that uses a gradient OQNLP algorithm. The research is based on field measurement data from a 210-km-long area at the northern coasts of the Gulf of Oman. This modeling approach allows the fitting of various spectral models. Accordingly, three directional spectrum models with combinations of frequency and directional spreading functions have been evaluated and proper models for directional waves have been presented. On the other hand, the introduced optimization algorithm is modified by adding a constraint to zeroth-order spectral moment (m0) value to improve the fitting accuracy in t

The ability of the Gaussian model to represent the primary system in a double-peaked spectrum is examined in comparison to the one regenerated by the JONSWAP model, while for the secondary system the JONSWAP model is implemented. The research is based on two series of measurements in the northern part of the Gulf of Oman (i.e., 2006–2007 and 2016). It is argued that the shape of the Gaussian model near the peak and the limited extension of its right-hand side tail compared to the JONSWAP model increase the performance of calibrated double-peaked spectra. In other words, using the Gaussian model for the primary system contributes to directly improving the representation of the primary system, and indirectly enhancing the description of the

A numerical model based on WCSPH method is utilized to simulate wave propagation over a pipeline. A hybrid approach is introduced to absorb outgoing waves based on gradual decrease of fluid velocity in an absorbing layer and using sloping beds simultaneously. The interaction of both regular and irregular waves with pipelines located on porous and impermeable sea-beds has been studied. The effect of pipeline distance to sea-bed on flow pattern and on the applied force is investigated for different geometries of pipeline protection by porous media and side slopes. Irregular wave spectra are studied and the model has been verified in comparison with other numerical and experimental data. The developed model simulates accurately the interaction

According to the challenge of global warming, trees play an effective role in reducing heat islands and improving thermal comfort. In this study, the impact of urban greening on microclimate and pedestrian comfort is studied using ENVI met v4 for a residential district in Tabriz, Iran. In-situ measurements of air temperature and relative humidity have been preliminary performed on ten points in the studied site and collected data used to successfully validate the model. Four scenarios with different trees species and patterns were simulated during typical summer and winter days, to assess benefits and disadvantages during different seasons, in terms of air temperature (Ta) and relative humidity (RH), mean radiant temperature (Tmrt) and phys

The form, size and orientation of the building are the most important effective parameters on internal climate and have direct effect on thermal performance of the building. The aim of this research is to investigate the amount of received radiation energy of vertical surfaces in buildings and to determine the appropriate form, aspect ratio and orientation of building in accordance with the hot-dry climate in the cities of Isfahan, Semnan, Kashan and Kerman. In this research, six polygonal forms, including square, rectangle with North-South and East-West orientation, hexagonal, octagonal, hexadecagon, and triacontadigon (circle) were studied. All the investigated forms had the same floor area and height, oriented to the South. The aspect ra

The Journal of Medicinal Plants has been published since 2001 under the supervision of Institute of Medicinal Plants (ACECR) and so far 74 Numbers and 12 supplements have been published. This journal is published quarterly and contains articles in basic and clinical sciences related to medicinal plants including pharmacognosy, basic and clinical pharmacology, basic and clinical toxicology, and pharmaceutics. The Journal of Medicinal of Plants is an open access journal, and all articles are free to access, download, share, and re-use. The types of articles published in the journal are: Research Article: The results of the authors' research. Review Article: Written by experienced researchers who have sufficient knowledge and sources of their

Introduction Due to the hot and humid climate of the southern coastal cities of Iran, radiation and airflow play a very important role in thermal comfort feeling. If the wind flow is compatible with shade, they cause more evaporation in the perspiration process and cool the body, allowing people to continue working at temperatures above the comfort zone. Therefore, the orientation of buildings in these regions should be determined simultaneously based on the optimum use of solar radiation and wind flow. This research aims to determine the best orientations of buildings, compatible with climate, in Bandar Abbas, Bushehr and Ahvaz cities, by surveying the amount of direct radiation energy received by the vertical surfaces of buildings. Resear

Calibration of double-peaked spectra based on partitioning of frequency spectra sometimes starts by assuming that relations existing between two observed peaks are valid through the calibration procedure. Here, often two facts are overlooked: each system (i.e., swell and wind-sea systems) in a typical double-peaked spectrum contributes to the other one, and swell system in its peak zone is highly asymmetric. Actually peak spectral densities and corresponding peak frequencies of partitioned systems are different from those observed in an integrated double-peaked spectrum. Besides, those observed as peak values are not good candidates of the peak due to the asymmetry of swell system. To highlight these issues, we examine 2 different methods t

The response of a composite breakwater against wave load is numerically investigated using Smoothed Particle Hydrodynamic (SPH) model. Permeability of the stone layer beneath the caisson is implemented in the model and a new scheme free of any tuning parameter is introduced to estimate the dynamic friction forces transitionally applied to the moving caisson. To overcome pressure noises inside the porous medium, a treatment based on δ-SPH scheme is utilized and its performance is verified by modeling a simple hydrostatic condition inside a homogeneous porous medium. The model ability in simulating fluid flow through porous media is approved by modeling dam break flow through a porous block. In addition, a caisson breakwater with an impermea

In the Archaeological excavations have recovered dates a fully conscious with classified data was used specially aims deformation one of these cases are symbolic statues. Statues, the great cultural leap that occurred in New Paleolithic represents a complex process of social The victim as well as the data symbol or a legend or goddess of fertility goddesses and religious icons and some have called almost every toy figurines and decorative Statue of nudity are common Female And a big emphasis on the chest and abdomen, and above all, an emphasis on pregnancy and childbirth are usually chopped sage statue are discarded and a handful of mud either stone Female Statues and tails that are not broken

The smoothed particle hydrodynamics (SPH) method is one of the powerful Lagrangian tools for modeling free surface flows. However, it suffers from particle disorder, which leads to interpolation and numerical errors. To overcome this problem, several techniques have been introduced until now, among which the particle shifting technique (PST) based on Fick's law is an efficient one. The current form of this method needs tuning parameters to fulfill numerical stability criteria. In this study, to eliminate calibration factors, a new shifting coefficient is derived theoretically based on particle positions before and after shifting, regardless of other parameters such as velocity, pressure, time step intervals, etc. The only required input is

Wave run up and overtopping are two important processes in design of coastal structures and in definition of their crest elevation. Wave run up in contribution with wave breaking generates local turbulences as well as large deformations around free surface profile. Smoothed Particle Hydrodynamic (SPH) method as a powerful Lagrangian method in modeling free surface flows is modified and applied in this study to estimate wave run up properly. Two modifications ie stepped and smoothed approaches are introduced to implement bed shear stress in SPH models. The results are compared with reliable predictions based on experimental and analytical studies. It is concluded that neglecting bed shear stress as a common practice in SPH methods can genera

Wave run-up and overtopping are important factors in design of the crest elevation of coastal structures. On the other hand,large deformations occur in water surface during wave propagation and breaking. Due to the ability of Smoothed Sarticle Hydrodynamics method in simulation of the aforementioned phenomena, this method is used in the current study. In addition to free surface boundary, characteristics of seabed materials and their resistant force have a direct effect on the amount of wave run-up. Inclusion of this force in numerical models will improve the results. In this regard, two new approaches have been introduced in this study to apply friction forces to bedrock’s adjacent particles. These approaches are defined based on uniform

Construction of a new coastal structure changes the stable shape of the shoreline. This issue generally leads to sedimentation and erosion around adjacent structures due to changes in Littoral Sediment Transport (LST). This mechanism is considerably more complicated in crenulate-shaped bays than in straight shorelines. Therefore, special theories have been introduced for these bays. In addition to the above-mentioned difficulties, using two-dimensional long-term morphological models with considerable run times is not practical in most real cases. Instability and numerical errors may also be occurred due to the complicated forms of shorelines. The aim of this research is to introduce a proper morphological model for South-Eastern shorelines

An important point in design of coastal structures is their structural response to design waves. In this study, wave interaction with a caisson breakwater is studied numerically by means of a modified SPH method. An efficient method is introduced to take into account the static and dynamic sliding forces at the interface boundary beneath the caisson. After a validation test, a time history analysis is done to investigate the structural response of a caisson breakwater against waves. The results are compared with experimental data as well as with similar numerical outcomes. There are good compatibilities between the experiments and the predicted values regarding both caisson movements and applied wave forces. In addition, three different sol