مجله علوم و فنون دریایی
سال بیست و دوم شماره 3 (پاییز 1402)

Energy is the driving force behind all human activities. The scope of these activities is from day to day activities to macroeconomic activities in each country. Today, the world is moving towards lowering energy consumption and increasing the efficiency of using existing energy, and the issue of energy substitution in different contexts in scientific communities is under consideration. Energy is a major factor in the development of every country that needs more effort to achieve sustainable development. The transportation sector plays a key role in achieving development. Therefore, it is important to study the effective factors in this sector as the second largest energy consumer in Iran and in the world. In this study, a transport function model for the transportation industry in Iran is established and the factors of production include capital, energy and labor. The production stretch and substitution of each of the factors of production have been calculated and analyzed, respectively. The results show that during the period of 1362 to 1391, there is a relatively good substitution between energy and capital in the transportation sector in Iran. This means that, through greater allocation of capital in the transportation industry, energy-saving technology can be continuously upgraded and a succession of capital and energy can be realized. Also, the effect of substitution of capital and energy on the reduction of pollutants from fuel consumption in the transportation sector was investigated.

his study aimed to investigate the effect of selenium and magnesium nanoparticles and their composition on growth performance, nutritional indices, survival rate and hepatic accumulation of nano selenium and nano-magnesium in Asian Sea Bass (Lates calcalifer) with mean weight: 32.78 ± 1.16 g for 42 days. After four weeks of acclimation to the experimental conditions, 96 fish were randomly distributed in 12 fiberglass 300-liter tanks in equal numbers. Four treatments including nano-selenium and nano-magnesium free as control group, 4 mg nano-selenium treatment, 0.5 g nano-magnesium treatment and combination of 4 mg nano-selenium and 0.5 g nano-magnesium were investigated in this study. The fish were fed daily in two times based on station. Fish biometry was performed in all treatments at the end of the experiment. Samples needed to measure liver accumulation were collected at the end of the period. The results of this study showed that the final weight in the treatment of selenium nanoparticles was significantly different (P <0.05), percentage of body weight gain and specific growth rate in selenium + magnesium nanoparticles treatment was significantly different compared to the control group (P <0.05). Nutritional indices of protein yield coefficient, feed intake and feed conversion ratio were not significantly different among experimental treatments (P> 0.05). The results showed that the survival rate was not significantly different among experimental treatments (P> 0.05). The highest levels of selenium and magnesium accumulation in liver were related to selenium nanoparticles and selenium + magnesium nanoparticles, respectively, which were significantly different from other treatments (P <0.05).

Measurement of heavy metals in water, sediment and fish has always been a measure of environmental pollution and its impact on the human ecosystem. In this study, sampling was done from Khorramshahr fish market and sampling of Lutjanidae, Sciaenidae, Cynolossidae, Psettodidae, Stromateidae and shrimp muscle. According to the results, the concentration of Fe heavy metal was higher than all other metals in all studied samples. Concentration changes were observed for other heavy metals in fish muscle tissue and shrimp Metapenaeus affinis, respectively, Zn> Cu> Ni> Pb> Cd. The highest concentrations of Cd and Pb in salted and shelled fish with 0.19 and 0.24 µg / g and for Fe and Zn in salted fish were 14.14 and 8.42 µg / g, respectively. Metals were measured with concentrations of 20.9 and 9.98, respectively. Iron and zinc concentrations in shrimp were 32.13 and 15.18 µg / g, in nickel fish 0.29 µg / g and finally, the highest concentration of Pb was observed in shrimp fish with 0.24 µg / g. The highest amount of contamination was observed in shrimp and Fe metal with a concentration of 32.13 µg / g. Whereas, the least contamination was observed in white halva. The reason for this was that the cadmium content was lower than the detection range.

Advances in remote sensing enable fast mangrove mapping the less need for intensive fieldwork, complex and heavy processing, and skill-based classification techniques. In this research, mangrove forest mapping was performed using Sentinel-2 satellite images in Google Earth Engine (GEE) in Hormozgan province in three ecosystems of Qeshm, Khamir, and Sirik. For this purpose, all steps of mapping these forests, including pre-processing and classification were performed in the GEE. The Modular Mangrove Recognition Index (MMRI) and classic spectral indices were also used to highlight the spectral differentiation of mangrove cover from the surroundings. To classify the image of the study area, three land cover classes were used: mangrove, non-mangrove, and sea (water). The classification was performed based on the random forest algorithm and accuracy assessment was evaluated in R software based on the K-fold validation method. The Qeshm site was demonstrated the highest accuracy among the three ecosystems with an overall accuracy of 98% and a kappa of 0.73. Khamir and Sirik sites were shown an overall accuracy of 97% and a kappa value of 0.71 and 0.70, respectively. The MMRI index was the most important variable in the RF classification in Qeshm and Khamir, while in Sirik, the SAVI index was the most important spectral index in mangrove map providing. The overall accuracy of over 95% at all three sites indicates that combining Sentinel-2 data using appropriate indices in the GEE is an effective approach to mangrove forest mapping

Organizational policies are constantly flowing in organizations. Paying attention to these policies and being influenced by people causes changes in the behavior of employees, which can bring about dramatic changes. In Khorramshahr Marine Science and Technology University, like the other organizations, organizational policies are influential, and people that are influenced by these policies show some behaviors in the organization. The method of this study is mixed and is a practical study. To identify the effective factors that creates triple political behavior in Khorramshahr University of Marine Sciences and Technology, Delphi technique was used. In the first part of this study ,10 persons of organizational elites were selected as the elites. Then, the items in three rounds were given to elites group to express their views. After completing the Delphi rounds, the adequacy of the Delphi rounds was declared with the Kendall coefficient, and 102 items were confirmed. In the second part, using a simple random sampling method, 196 persons of employees, members and students were selected to be investigated and thereafter they were asked to complete the prepared questionnaire. The collected data was analyzed using SPSS and smart PLS software. Path analysis method and significance coefficient t and significance coefficient p were used. The obtained results showed that organizational justice has the greatest impact on the occurrence of political behaviors in the field of financial promotion. Also, among the three identified variables, the organizational culture variable has the greatest impact on job promotion. Organizational justice has the greatest impact on public political behavior. Also, among the three influencing variables in terms of budgeting and goal setting, job promotion has the most impact. Using the results, the final model was obtained that shows the impact of organizational policies on the guidance of Khorramshahr Marine Science and Technology University employees in goal setting and budgeting.

One of the strategies that different governments use in certain circumstances to secure their national interests is to apply the theory of deterrence. Considering that today the main concern of the countries in the region and the great Western powers in the Persian Gulf region is the issue of security, and considering that the Islamic Republic of Iran has always rejected the interference of foreigners in the Persian Gulf region and emphasized on collective and local cooperations. As a result, Iran's views on security in the Persian Gulf and its policies have been shaped by internal factors such as opposition to the presence of foreign powers in the Persian Gulf region. The general result of these factors has led Iran to oppose any role for foreign powers, especially the United States, in the security arrangements in the Persian Gulf. In this research, using a descriptive-analytical method and using the theoretical framework of neoclassical realism and the theory of defensive realism, Iran's strategy in providing security in the Persian Gulf region has been studied.

Sea-based defense diplomacy, soft use of the navy through participation in activities such as student-centered exchange of maritime universities, visits by ships and submarines to littoral state, Communications of vessels at sea for coordination and in the fight against piracy and maritime terrorism, relief and salvation is institutionalized at the seas and oceans. In general, maritime defense diplomacy is a process that leads to increased maritime cooperation between the maritime institutions of the coastal states. From another point of view, maritime defense diplomacy is based on the peaceful use of one country's navy and defense and government institutions to cooperate with another country's navy, defense and government institutions in order to achieve a desirable result. The present study uses a descriptive-analytical method to investigate the role of the strategic navy of the Army of the Islamic Republic of Iran in the development of sea-based defense diplomacy. The findings of this study indicate that in general, the relations between the navy and the maritime industry related to defense affairs at the international level can be in the direction of macro diplomacy of a maritime country to protect and safeguard national interests. From this point of view, sending high-ranking naval delegations to participate in international Symposium such as IONS and the participation of various fleets in the form of shipping security fleets and training fleets of naval university students to international waters and visiting developing and developing maritime countries can have a significant impact on the promotion of sea-based defense diplomacy. Continuation of sea-based defense diplomacy can create a profound change not only in the field of sea-based defense but also in the field of maritime industry development and sustainable maritime development. Therefore, the promotion of sea-based defense diplomacy can play an important role in promoting and protecting national interests. In addition, the visit of naval training, peace and friendship fleet will strengthen public diplomacy, expand maritime relations with the littoral countries of the oceans and seas. Finally, the efficient and effective presence of the Strategic Navy in international waters has enhanced the security of the country's maritime transport lines such as non-oil exports, exports of crude oil and gas condensate, imports of basic goods and basic items of the country.

Offshore oil terminals are used as a cheaper and safer solution than shore terminals for unloading and loading tankers. There are different types of offshore terminals. Therefore, comparing the dynamic response of these terminals will be effective in identifying their strengths and weaknesses. The present study is to compare the dynamic response of the structures of three common offshore oil terminals, including CALM, SALM, and CMBM in environmental conditions under the Persian Gulf region. Simulation is used in OrcaFlex software to obtain structural responses including the tension created in the mooring line and hawser, motion the tankers connected to them. The results show that considering the same operating conditions, the maximum tensions created in the SALM terminal mooring are 2.7 and 1.3 times higher than the CALM and CMBM terminals, respectively. Also, the maximum tension in the SALM terminal hawser is 1.5 and 4.3 times higher in the CALM and CMBM terminals, respectively. As the environmental conditions become more critical, the SALM terminal mooring shows the most stability. By increasing the tonnage of the tankers from 45,000 to 320,000 tons, the maximum tension created in the CMBM mooring has the least change; This is while the maximum tension created in the terminal mooring of CALM and SALM increases by 100% and 156%, respectively. Comparing the displacement created in the tankers (during operation), it results that the displacement in the tanker connected to the CMBM terminal has a minimum size and the displacement in the tankers connected to CALM and SALM is almost the same.