مجله علوم و فنون دریایی
سال هجدهم شماره 4 (زمستان 1398)

Construction project of ports, jetties and other marine structures have more negative environmental effects than other projects. In this study, we investigated Environmental Impact assessment for the construction and exploitation of Yard-Valiasr Jetty in Khorramshahr Port using corrected Leopold and RIAM Matrices. Corrected Leopold Matrix results showed that none of the calculated effects and consequences are not at the threshold of the -3.1 degree. The RIAM Result also revealed that negative effects change more between neglected negative effects to moderate negative effects, but for exploitation phases, Water Ecosystem tolerates noticeable negative effects that confirmed corrected Leopold Matrix results. So base on two Matrices result and based on developmental impact of project on industry and transportation and also its compatibility with land use of area, the project could be run by incorporating mitigation plans and monitoring measures.

Refrigerated storage is the simplest of preserving for short time of fish. The aim of the study was to investigate the effects of refrigerated storage on the microstructure, proximate composition (moisture, protein, fat and ash), chemical (total viable nitrogen, pH, thiobarbituric acid, free fatty acid, water holding capacity), microbial (mesophillic count and psychrotrophic count) and sensory changes of Lutjanus argentimaculatus fillet during a 12-day period at 4 ºC. Fat and protein contents of Lutjanus argentimaculatus of fillet significantly decreased during refrigerator storage and moisture and ash contents of Lutjanus argentimaculatus fillet significantly increased during refrigerator storage (p

Marine transportation mainly includes fleet allocation, ship routing, and refueling issues. It should be noted that the issue of fleet allocation, route design, and planning of ships is aimed at minimizing the costs. In recent years, most shipping companies have faced difficult market conditions in terms of refueling and fuel prices. Given that approximately 60 percent of the cost of the ship is dedicated to its fuel, so fleet fuel costs are considered the largest shipping cost. In these issues often competitive conditions and uncertainty have been considered, that causes the complexity of the problem. In this study a liner marine transportation company is evaluated, that transfers cargo between different ports. The company requires to determine some decisions such as finding the optimal route, refueling and ship speed policy under price and fuel consumption uncertainty. Interactions of refueling and routing and allocation due to the need of refueling during the ship routes provide the importance and the need to examine these two issues together. So in this problem, we are going to define the ship routing while we are going to determine the location of refueling and the speed of the ships based on the fuel prices.

One of the most important issues related to arc ducts is the erosion of the river bank in the outer arc, which is largely due to the existence of secondary currents, in which the mechanism of these currents was elaborated in the previous section. Protecting and fixing the river walls generally involves both direct and indirect methods (relaxants and deviators). One of the most important diversion protection structures is river flows. In this research, hexapod materials were evaluated for scouring in permeable spills. The results obtained from the simulation show that the use of Hexapod spray with 12, 20, 27 and 35% permeability reduced scours by 17, 27.9, 38 and 45.3%, respectively, compared to the control without permeability. Increasing the permeability of the hexapod spoil reduces scouring around the spillway. Increasing the permeability of Hexapod spray guns from 12 to 35 percent resulted in a reduction of sputum by 34.1 percent. This phenomenon is due to the easier flow of water through the hexapod sprayer and creates less pollen, which reduces scouring. Also, with an increase in the landing value from 0.2 to 0.36, the scour is 11.8 times higher. Of course, it should be noted that increasing the landing number increases the permeability of the spillway to increase scouring. So that with the installation of permeable sprinkler 35% in the number of 0.2 and 0.36, respectively, we saw a decrease of 20 and 61% scouring compared to the control model, respectively.

Feeding habits and feeding indices of catfish Plicofollis tenuispinis (Pay, 1877) in coastal waters of Qeshm island around Gouran region were studied during May 2016 to April 2017 by sampling 15 fish per month throughout one year. Mean value of fish fork length was 24.43 ± 2.52 cm. Relationship between fork length and total weight was determined as W=0.012 FL3.066, which considering the amount of b, indicates the isometric growth of P. tenuispinis. The highest amount of gastrosomatic index was in spring and the lowest was in winter revealing that the highest feeding intensity was in spring for this species in coastal waters of western Qeshm island. Mean value of vacuity index was calculated 35.01 ± 15.91 for this species that ranks this species as a relatively edacious species. Season based analysis of VI data indicated that the lowest amount of VI or the highest number of full stomachs was in spring. Evaluation of food preference index showed that fish, shrimp, bivalves, crabs, mollusks and algae constituted 52.45, 21.31, 5.73, 4.91, 3.27 and 0.81 percent of stomach contents, respectively. Therefore, fish were the main and shrimps were the second prey priority. Crabs, bivalves, mollusks and algae were the accidental preys consumed by this species. Index of relative length of gut was 2.08± 0.26 indicating that P. tenuispinis is omnivorous in coastal waters of western Qeshm island.

There is a different method for increasing the resistance and quality of engineering of soils, one of the most suitable ones is dynamic compaction. In this method, weights are released from the specified height and, as a result of collision with the ground, the soil will be compacted. In this research, field experiments were initially initiated. Then using the results obtained in this section, the soil dynamic compaction was modeled. In order to do the modeling, the present study was conducted using FLAC two-dimensional software. Due to the implementation of various designs in the city of Abadan, the area was selected as the site of the project After field experiments, mechanical properties of the soil were extracted and then modeled with the definition of test patterns. The result of this research show that For all conditions of modeling, the maximum deformation of soil was observed in the hammer Cutoff area, which decreased in depth of soil. Also, the results indicate that effective stress in soil under dynamic density decreases with increasing depth.