فهرست مطالب بهروز میرزایی

Insurance frauds are one of the most harmful concerns of insurers and policyholders in all insurance products. One of the most important factors affecting insurance fraud in this research is religiosity, individualism, social welfare and trust .Frauds cause mistrust and disintegration of the social and economic system.The purpose of this research is to investigate social factors affecting third party insurance frauds. This research is based on a mixed approach applying a exploratory approach.In the qualitative part,the statistical population included all experts in the field of insurance and economic sociology which reached the saturation limit of 26 experts using the purposeful and Snowball sampling method. In the quantitative part, the statistical population includes 4,652,510 third-party insurance policyholders in Tehran,which 384 individuals were selected as a sample by cluster sampling method.The validity of a questionnaire was confirmed by the face validity method and its content and reliability was confirmed by using Cronbach’s alpha method.The qualitative data analysis was done through thematic analysis method and the quantitative data was done through confirmatory factor analysis method with the aim of Amos 21 computer software. Among the social factors, social welfare, trust, religiosity and individualism are respectively -0.56, -0.52, -0.43 and 0.36 directly and religiosity with factor load (-0.447) indirectly from the model have supported the measurement. According to the findings of the qualitative part of the research, a total of 57 basic themes,19 organizing themes, and 4 overarching themes(social welfare, trust, religiosity and individualism) have been identified that could be effective on third party insurance frauds.

The present research was conducted with the aim of exploring and explaining organizational factors affecting third-party liability insurance violations in the Iranian insurance industry.

The current study is based on a descriptive-exploratory mixed methodology. The statistical population of the qualitative part of the study includes experts from the fields of insurance management and economic sociology and development. The survey was conducted using a purposive and snowball sampling method of 26 experts until saturation. The statistical population of the quantitative part of the study included employees of Tehran insurance companies. A total of 354 people were selected as a statistical sample using a cluster sampling method. The instrument for data collection was semi-structured interviews with experts in the qualitative part and questionnaires in the quantitative part. The validity of the questionnaire was confirmed by form and content methods and its reliability by the Cronbach's alpha method. The data from the qualitative part of the study was analyzed using the thematic analysis method and the data from the quantitative part using confirmatory factor analysis with the Amos21 software.

Based on the results of the qualitative part, a total of 52 basic themes, 18 organizing themes and 5 inclusive themes (organizational justice, organizational commitment, informal organization, organizational culture and legality) were identified. According to the results of the quantitative part, organizational justice and organizational commitment have a negative and inverse effect with -0.84 and -0.56, respectively, and the variable of informal organization has a positive and direct effect with 0.54 on the violations of employees of insurance companies operating in the field of third-party liability insurance. The variable of organizational justice had an effect on the violations of insurance company employees through the influence on organizational commitment and informal organization.

Based on the research findings, it is suggested that the organizational factors presented in this study should be considered in the strategic plans of the insurance industry in addressing insurance violations and should be emphasized by insurance companies. In the area of organizational justice, it is suggested that in order to restore organizational justice, the mentioned values should be considered among the employees of the insurance companies and the implementation of justice in the organizational processes. In terms of organizational commitment, it is suggested that the dimensions of organizational commitment considered in this research should be considered as a basis for improving the organizational commitment of employees. In relation to informal organization, it is also suggested that if there is a positive attitude towards informal organizations, their existence should be used in line with the objectives and strategies of insurance companies.

The role of great industries such as oil, gas petrochemical is essential in the world economy, however, the most problem of these industries is the abandoned pollutants in the environment. In this study, the removal of two major oil pollutants, benzene, and toluene was investigated in the presence of two new and native fungi called Aspergillus terreus and Exophiala xenobiotica. The factors affecting the removal process consist of temperature, time, concentration and pH. The results showed that the highest adsorption of pollutants occurs at 25 ℃ within 10 days of contact time with fungus A. terreus and 25 days for fungus E. xenobiotica in a way that both pollutants have a concentration of 5 ml/lit and pH=7. A comparison of the performance of two fungi on the removal of pollutants showed that in the condition in which the effect of concentration, contact time, and the temperature was investigated E. xenobiotica is successful in removing benzene and A. terreus showed better performance when the effect of pH was evaluated. In contrast, in the removal of toluene, the A. terreus showed better performance in all conditions. Finally, based on the result of this research, it could be concluded that the bioremediation process using new fungi is a promising and environmentally compatible solution to eliminate oil pollution. In general, based on the results obtained under the optimum conditions of all four parameters, A. terreus had the best performance for benzene and toluene contaminants with the removal of 68.35% and 84.27%, respectively.

In recent years, an outbreak of a new coronavirus, scientifically known as SARS-CoV-2, has led to a worldwide new infectious disease called Covid-19. Based on some reports, this virus stays after infection in the feces and consequently in the wastewater up to seven months, so examining its presence in the wastewater can be useful to understand how the disease is distributed in different parts of the city or region. This study aimed to investigate the presence of the SARS-CoV-2 virus in different parts of the Shahroud city wastewater collection network and treatment plant.

The 35 wastewater samples were collected from different partsof the wastewater collection network and wastewater treatment plant of Shahroud city. The samples were immediately transferred to the SARS-CoV-2 reference laboratory and concentrated by the polyethylene glycol (PEG) method. After extraction of the virus genome, the viral genome was amplified to check the presence of this virus by PCR method.

The results showed that 11 of the 35 wastewater collected samples were positive. All samples taken from the influent of the municipal wastewater treatment plant were positive. Also, except for one, in all of the samples taken from the effluent of the municipal wastewater treatment plant and Imam Hossein (AS) Hospital wastewater plant, coronavirus was observed. However, only one sample taken from the wastewater collection network of Shahroud city was positive.

Due to the confirmation of the presence of Coronavirus in the wastewater collection network and treatment plant, regular monitoring of municipal wastewater is recommended to predict the spread of a new wave of disease in the community.

Currently reserves are proven to be the most economical method of oil and gas storage worldwide. In this work, the effects of different parameters on possible incidents of oil storage tank via modeling and analysis with the PHAST software was investigated. In this modeling, a pressurized crude oil storage tank with an input pipeline was considered and the possibility of leakage from the pipeline was studied. The results showed that, depending on the weather conditions, the diameter of the simulated oil pond can be extended up to 40 meters. Moreover, in the wind and assuming a fire pool in the oil pond, the heat radiations with an intensity of 4 kW/m2 can affect the pond up to a distance of 20 meters. The areas affected by the wave from explosion and flash fire were also 27 and 30 meters, respectively. The results also showed a high evaporation rate of oil the first time  and after about 2000 seconds, due to lower oil in the pond, the rate of evaporation is reduced and leads to a decrease in the radius of the pond. The rising storage tank temperature, as well as the amount of evaporated oil over time, are the most important issues, which make it difficult to control the system and also endanger the safety and health of the environment.

Inter Simple Sequence Repeat (ISSR) analysis was performed to evaluate genetic diversity and genetic structure of six Capoeta trutta populations from two main watersheds in the Kurdistan province. Fish samples were caught from the Choman, Shooei, Garmab Rivers in the Choman watershed and from the Gheshlagh, Gavarood, Sirvan Rivers in the Sirvan watershed. From six used dinucleotide primers, three ((AG)9C, (GA)9C and (AC)9T)) generated discernible bands. Fifty six clear and repeatable bands were generated throughout six populations. The percentages of polymorphism were 80.00, 82.98, 82.61, 85.71, 79.60 and 80.49 within the Sirvan, Gavarood, Gheshlagh, Choman, Garmab and Shooei populations, respectively. The average values of heterozygosites were determined as moderate to high within the studied populations. The intrapopulation genetic diversity indices were significantly higher in the Choman population than others. The analysis of molecular variance revealed 89 percent variation within populations whereas only 11 percent between populations. Population comparisons based on fixation index (Fst) revealed low to moderate differentiation between six studied populations. However there was no significant differentiation between populations as testified by exact test. The results showed that environmental conditions to maintain genetic diversity of Capoeta trutta populations in two watersheds are moderate.

Nanotechnology is of significant importance in many scientific fields. In view of engineering problems, nanomaterials have found wide practical applications. In this work, iron oxide nanoparticles called maghemite (γ-Fe2O3) were synthesized. The synthesized nanoparticles were used to adsorb asphaltene from prepared asphaltene-toluene solutions. Asphaltene adsorption kinetic behavior was modeled using experimental data. For the synthesis of maghemite nanoparticles, the co-precipitation of ferric and ferrous ions method as a simple and inexpensive method was selected. The crystalline structure and morphology of synthesized maghemite was investigated using X-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. The nanoparticles were also characterized by using FT-IR spectrum. The results of these analyses showed that the γ-Fe2O3 nanoparticles had a crystalline structure with a size smaller than 50 nm and were spherical in shape. The maghemite nanoparticles were used for the adsorption of asphaltenes. The results obtained from adsorption kinetics analysis showed that asphaltene was rapidly adsorbed onto γ-Fe2O3 nanoparticles, and equilibrium was achieved in less than 2 hrs. The Lagergren pseudo-first-order and the pseudo-second-order models were employed for determination of the adsorption kinetics. It was found that the kinetic results were in good agreement with the pseudo-second-order model.

In this paper, a new mixing rule for predicting the surface tension of liquid mixtures is presented. The resulting equation is provided by a combination of Gibbs- Vollmer relation and NRTL activity coefficient model. The proposed model accurately predicts the surface tension of aqueous and non-aqueous solutions in a wide range of concentration. In order to evaluate the ability of this model, several surface tension of binary liquid systems were measured tensiometer (Kruss K20 Easy Dyne). The experimental data available in the literature also were used to prove the accuracy of the model. The results showed that the proposed model can predict accurately the experimental data in a wide range of concentration. Data of non-aqueous solutions were predicted with high precision as absolute average error of less than 1% was achieved for most of these systems. For aqueous systems with a high degree of non-ideality the deviation from experimental data is higher than other systems (up to 10%). This error occurred because the molecules with strong hydrogen bonds that can form a complex non-ideal mixture, even the use of accurate activity coefficient model could not eliminate completely the error. However, the model predictions are satisfactory and acceptable.

In this paper we investigate grayity IR effects on quantum machanics considering minimum momentum. First، we investigate afew cases in quantum mechanics by minimum momentum، also we show hydrogen atom spectrum is corrected and produce limit on minimum momentum by prices measurements done on hydro-gen atom. also we investigate aharonove-bohm eff-ect and show its topological phase is corrected. Con-sidering appropriate experiments، this corrections will be observed

 An enhamced scheme is introduced for the solution of two dimensional umsteady euler equations. The Finite- Volume method of jameson et al. is modified by devicing a pnessune sensor in cell Flux calculations.
Then the discretized gorerning equations ane relaxed in time until na steady state is reached. An appropriate model for the artificial dissipation was also employed. Several tests wene conducted by this method on am o grid in the transonic regimes.
The obtained numerical solutions wene companed by the solutions of jameson efal, in which good agreement would exist