محمدرضا خیر اندیش

In general, the consistency of the geometric design measures the level of relationship between the driver's expectations and the behavior of the road geometry and it is an important factor in road accidents. Evaluation of road geometry by inconsistency indices requires road geometry information and an operating speed profile. Due to the lack of road geometric information in Iran, it is difficult to study this field. In this research, the method of obtaining road geometric information from street maps was first discussed, and then, based on this information and operating speed models, the speed profile was drawn for the road under study. After applying the segmentation methods, for each of them, the relationship between inconsistency indices and types of accidents has been investigated by safety performance functions with a Poisson or negative binomial model. The results showed that the inconsistency indices have a significant effect on overturning type accidents. In terms of significance level, Castello's inconsistency index, which is calculated using the inertial speed (for each point by weighting the operating speed in a certain period of time before that point) showed the best relationship with overturning accidents on two lane rural road. The development of inertial speed calculation methods and optimization of Castello's inconsistency index relationship with overturning accidents, showed that the value of the time interval before each point is 14 seconds and the value of alpha equal to 4.1 has the best performance in predicting overturning accidents.

During the summer of 2022, an infection appeared in siberian sturgeon (Acipenser baerii) reared in raceway system of Fars province. 30 pieces of fish with clinical symptoms were collected from the ponds. Bacterial samples were cultured from kidney tissue of fish using brain heart infusion (BHI) agar according to standard method. Gram staining, biological and biochemical tests were performed on the bacteria isolated from the samples; In addition, polymerase chain reaction (PCR) was performed on SrDNA16 gene. Initial isolation of bacterial culture colonies and biological and biochemical tests on the isolated bacteria showed that the isolates corresponded to the genus Staphylococcus. The results of the PCR test on the SrDNA16 gene with specific primers with accession number MK348063 in the gene bank created a band of 1500 base pairs (bp). The results of the analysis showed that the sequences belonged to Staphylococcus epidermidis with 100.00% similarity. This is the first report of the isolation of Staphylococcus epidermidis species from Siberian sturgeon (Acipenser baerii) farmed in southwest Iran. It was concluded from this study that further studies are necessary to investigate the pathogenicity of these organisms and their effects on Siberian sturgeon and other strains of sturgeon.

The use of non-active defense principles at different levels of urban planning is a solution to reduce vulnerability to potential hazards, which unfortunately has not been given much attention. In this research, parts of the 22nd district of Tehran city were considered for the construction of a water treatment plant. The suitable map of the land for the construction of the treatment plant was obtained in five optimal areas and the places were classified in five weighting categories. The use of non-active defense principles at different levels of urban planning is a solution to reduce vulnerability to potential hazards, which unfortunately has not been given much attention. In this research, parts of the 22nd district of Tehran city were considered for the construction of a water treatment plant. The suitable map of the land for the construction of the treatment plant was obtained in five optimal areas and the places were classified in five weighting categories.

The total purpose of this study was to investigate the effect of mobile social networks on the social relations of families in the western areas of Tehran. Theoretical Foundations were collected from different sources and based on this, research model was designed. In this study, the impact of telegram audio-visual and multimedia content on social relations of families, the effect of  spreading the culture of moral construction on the social relationships of families, the effect of the telegram virtual addiction on social relations of family, the effect of making false identity in telegram on social relations of family ,The effect of spreading the culture of fashionism in telegram on the social relations of families and the effect of the spread of emerging sects in the telegram on the social relations of families has been discussed.

This research is usefully in terms of purpose and in terms of descriptive-analytical method with a survey approach. In this study, data collection is done by library study method (records, books, journals and cyberspace). To compile research literature on exploratory studies in cyberspace for content analysis, the survey method was using the closed questionnaire tool and Based on the questionnaires, after conducting the necessary studies and based on the questions mentioned in the research, the statistics were compiled using the 5-point Likert method and distributed among the sample population. The statistical population of the study included citizens living in the western areas of great Tehran, which according to the latest census, has been announced as one million and 770 thousand people. Using the cluster sampling method, 300 people were selected as the sample population; then, the data collection operation was examined through a 34-item Likert questionnaire using a reliability and validity scale and the obtained data using descriptive statistics and The inference (analyzed by Kolmogorov- Smirnov, and Friedman tests) was analyzed.

The results of the tests performed on the priority of the effectiveness of each of the six independent variables show that the Telegram social network has the greatest impact on the creation of false identities and the least impact on the spread of emerging sects; Therefore, based on the results of these tests, practical and research suggestions have been made.

On the base of the population areas and sensitive military centers and also developing underground civil projects such as buried tunnels in the north of Tehran such as Metro lines projects and military centers, there is the possibility of military threats due to the air attacks of the enemy countries because of the destructive effects on the urban operations. The penetrate missiles are of the dynamic instability factors that threaten the safety of the tunnels. In this study, by using of the numerical analysis, investigated resistance of the considered tunnel against explosion of bunker buster GBU-28 in the various deeps and finally the minimum distance among explosive cavity and crown of the tunnel that it remained stable in the explosive tensions situations determined about 25m. In the distances lower than 25m both critiques of replacement of crown of tunnel and the breaking point indicated instability of tunnel under load due to explosion.

Nowadays, due to hostile threats, most critical and important structures are built underground. Being underground and the camouflage and concealment of these structures impose certain limitations and conditions on their mechanical installations that are never considered for other buildings. The appropriate design of mechanical installations of underground structures with the passive defense approach for normal and critical conditions are so indispensable and sensitive that in case they are designed inappropriately, not only their vulnerability will not reduce but also an underground structure can be turned to a mass cemetery in this regard. Because these installations are easily detectable and vulnerable and also the most important part of an underground structure. This article intends to transfer the experience of its writer regarding design considerations of ventilation and cold and warm facilities of underground structures with the passive defense approach, particularly the camouflage and concealment issues. The ordinary methods of air conditioning and the advantages and disadvantages of each are investigated and then taking the whole technical and economical and passive defense issues into considerations, the appropriate cold and warm and ventilation system of a typical underground structure is suggested. Finally, the executive solutions to prevent the entrance of smoke and contamination to the personnel assembly area and also solutions for the camouflage and concealment of fans and also exhaust air shafts, are explained. The said executive solutions have been already employed in various projects and their performance has been approved which due to their confidentiality nature, their technical details are excluded.

Throughout history there have been various forms of aggression and threats, but in the era in which we live, threats have emerged with more sophisticated methods and techniques.Producing destructive weapons systems and ready-to-fire systems, are considered the greatest threat to humanity. In contrast to the approach of deterrence and defense and in order to acquire advanced missile technology, maintaining such systems are among the top priority of every nation. The design of missile sites and silo-launched missile platforms by applying passive defense engineering provisions will greatly reduce vulnerability of facilities, equipment and manpower and will facilitate defensive operations and endure survivability.In this research, after the analysis of threats and while reviewing the two types of missiles, the American transcontinental Minutemen and the Russian Satan, ground-based silo-launched platforms and an array structure are described. Then vulnerability of silo launchers against threats, in particular, nuclear ones, have been explained and the methods of protection against nuclear explosions have also been signified. This research continues to introduce the passive defense engineering considerations such as site location, camouflage, concealment, deception, dispersion, hardening and fortifications as major factors in the design of missile sites and silo-launched platforms. The research uses empirical and analytical research methods which include interview, reviewing documents, library resources and information networks.