مسعود محمودی

Gas metal arc welding (GMAW) based wire-arc additive manufacturing (WAAM) is a promising manufacturing method widely used in various industries. In this study, for the first time, a new type of combined electrode wire with multi-element composition has been designed and developed for arc additive manufacturing of a composite alloy Fe rich-Al-Cu-Ni alloy. GMAW-based WAAM technique technology composed of 4 filaments and 4 elements has the advantages of high deposition efficiency, self-rotation of welding arc, and energy-saving capability. Thin composite alloy walls were fabricated under pure CO2 gas using GMAWbased WAAM technique technology. To investigate the effect of the parameters introduced by the gas metal arc welding process based on wire arc additive manufacturing, the produced components of the sample layer by layer with different parameters after production are characterized by scanning electron microscope morphologies, X-ray diffraction Microstructural observations of the developed combined electrode reveal (i) BCC and FCC phases, (ii) Good bonding between layers and (iii) defect-free microstructure. Therefore, an experimental design using the Taguchi method was used to determine the parameters affecting the studied properties, including yield strength (YS) and elongation (E). The developed combined electrode alloy exhibits high compression strength (~294 GPa) coupled with high elongation (~0.22%) values (possess both strength and ductility). It has been identified that by varying the heat input via torch travel speed, the microstructure and mechanical properties of the combined electrode can be controlled. Therefore, optimizing GMAW process parameters to produce effective products is of great importance. The experimental results show that voltage and wire speed are the dominant variables that affect the values of YS and E at the test surface. In addition, the contribution of each factor to YS and E was determined. Which can be effectively Corrected with this method.

Today, the wire arc additive manufacturing process is based on gas metal arc welding as one of the electric arc fusion processes, widely used in the industry due to its high efficiency. The correct selection of input parameters directly affects the welding quality, and by controlling those parameters, the amount of welding material can be reduced, its properties can be improved, and then the efficiency of the process can be increased. In this research, the production of a composite sample with a combined electrode by gas metal arc welding (GMAW) was investigated. At first, the welding speed, voltage, and wire speed were selected by studying and checking the effective parameters of the process in the wire and arc additive manufacturing (WAAM) by gas metal arc welding. Then, in order to evaluate the effects of effective welding parameters, three three-level factors were designed by the Taguchi method in Minitab software with an L9 array-related experiment. After performing the appearance review process, tensile and microhardness tests were performed. The tensile test results showed that the highest tensile strength is 294.327 MPa in the sample with a welding speed of 86 mm/min, voltage of 32 V, and wire feeding speed of 6 m/min. The microhardness test results showed that the highest value of microhardness was 463.1 Vickers for the sample produced with a welding speed of 86 mm/min, voltage of 27 V, and wire feeding speed of 5 m/min.

Protected areas are among the renewable natural resources that have a special position due to having many environmental values. The model of environmental destruction is one of the methods of evaluating the effects of the environment, which analyzes and quantitatively determines the effects of human activities in the regional scale or watershed or any type of management unit. The purpose of this research is environmental impact assessment of development with using the destruction model and geographic information system (GIS) in Ashtrankoh protected area. First, Ashtrankoh protected area was divided into 554 grids and using field observations, opinions of experts and local people, and available information and maps, the number of 11 factors of destruction were identified and their severity was determined. Then, the ecological vulnerability and physiological density were calculated and then the destruction coefficients were obtained using the destruction relationship. Then, the ecological vulnerability and physiological density were calculated and then the destruction coefficients were obtained using the destruction relationship. Finally, all the networks were divided into 4 zones based on the fuzzy theory, with the ability to develop more, in need of reconstruction, in need of protective measures, and non-developable. According to the final results, out of a total of 554 networks, 524 networks, which is equivalent to 94.58% of the area of the Ashtrankoh protected area, are susceptible to further development, 28 networks, which is equivalent to 5.06% of the studied area, need to be reconstructed and 2 networks, which are equivalent to 36. It occupies 0.36% of the protected area of Ashtrankoh, they need protective measures.

The rules of divorce are among the most important rules, which are related to public order. For this reason, the rule of private will in divorce is limited. According to jurisprudence, the husband can divorce the wife in person or by proxy at any time. However, in Article 1133 of the Civil Code Amendment, this path was amended and the man has the right to divorce his wife only by going to court and observing the provisions of the law. Divorce is a ceremonial rite; That is, in addition to the will and ability of the couple, there must be rituals such as divorce, chastity, and the presence of two just male witnesses. But public order and social interests required that, in addition to substantive formalities, the legislature establish formal formalities such as going to court, a certificate of the impossibility of conciliation or divorce decree, and the registration of divorce. The guarantee of non-observance of the essential formalities of divorce is void. But the legislature is silent on guaranteeing the civil performance of formalities. Some people believe that because divorce is done by the Shari'a rules, non-observance of formalities (formalities) does not invalidate it and only guarantees criminal execution. Others believe that the rules of dissolution of marriage are among the laws of public order, the non-observance of which invalidates the divorce. In general, given that public order is an exception in private law, the legislator's silence can not be considered a breach of divorce without going to court or divorce without registration; Because the principle is based on correctness and non-invalidity. The effect of establishing these formalities, as stated in the court rulings, is that litigation proving a normal divorce cannot be heard; Because divorce has to go through a specific legal process.

In Wire and arc additive manufacturing (WAAM) based on Gas metal arc welding (GMAW) is one of the methods of manufacturing metal layer by layer. One of this method's basic steps is predicting the welding geometry created in each welding step. In the current research, an experimental study was conducted in this field considering the effective parameters of welding geometry. For this purpose, three parameters of voltage, welding speed, and wire feeding speed were considered as effective parameters on the welding geometry of the process. The width and height of the weld bead was selected as the answer according to the type and application of the research. The least squares support vector machine was used to model the welding geometry in the process. The results obtained from the regression (R2) of train, test, validation, and total were 0.945, 0.793, 0.894, and 0.881 respectively. The comparison between the experimental data and the model data shows the significance of the proposed model.

Due to a dispute between the branches of the Court of Administrative Justice regarding the jurisdiction of this institution about legal claims on behalf of Shahed University, a unanimous decision was finally issued, citing the "Law on the List of Public Institutions" and the "Statute of Shahed University". The university was recognized as a public institution affiliated with the Martyr Foundation. However, "Article 3 of the Civil Service Management Law" states in a definition of a public Institutions: "A public Institutions is a specific organizational unit that: 2. More than fifty percent of its annual budget should be provided from non-governmental sources; "Is responsible for duties and services that have a public aspect." First, the university is not approved by parliament; Because this university has been established by Article 1 of its statute in line with the historical decree of Imam Khomeini. Secondly, despite the stipulation of Article 4 of the Shahed University Statute on the financing of the University by the Shahed Foundation, a review of the budget text of previous years indicates that the entire university budget in a specific row (No. 120100) in the budget law And is in charge of the state treasury; While the second part of Article 3 of the law stipulates that more than fifty percent of its annual budget should be provided from public Institutions sources. Therefore, considering the delay of the "Civil Service Management Law adopted in 2007" compared to the "Law on the List of Public Institutions adopted in 1994" and the great importance of providing resources and its amount in the recently approved law, it seems that the university can not be included in the scope. He considered public institutions as non-governmental and affiliated with the Martyr of the Islamic Revolution Foundation.

The presence of abundant calcium carbonate and alkaline soil reaction in most of the country's soils has reduced the bioavailability of some elements for plants. The application of some soil amendments such as sulfur and organic matter can improve the nutrient status of the soil. For this purpose, a factorial experiment was conducted in a randomized complete block design with 18 treatments and 3 replications on the underground soil of walnut trees. The experimental factors included Thiobacillus at two levels (without inoculation and with inoculation), sulfur (S) at three levels (0, 1000 and 2000 kg. ha-1 ) and organic matter (OM) at three levels (0, 5 and 10 T. ha-1 ). The results showed that S treatment significantly affects soil pH (p <0.01), P (p <0.05) and iron (Fe) concentration on soils beneath the tree covers (p <0.05). The highest P concentration (9.06 mg / kg) and available Fe (6.34 mg / kg) was observed in the treatment of 2000 kg. ha-1 of sulfur. Organic matter treatment significantly has changed the soil pH (p <0.01), available Zn (p <0.01) and plant available P and Fe concentration in soils beneath the tree covers. As the level of applied OM increased, the soil pH decreased. The highest concentration of available P, Fe and Zn was observed in the treatment of 10 tons per hectare of OM. Inoculation with Thiobacillus bacteria decreased the soil pH and increased soil available P concentration. According to the results, the simultaneous application of S, Thiobacillus and OM can increase the phytoavailability of P, Fe and Zn in soils beneath the walnut trees.

In this study, the effective parameters involved in the deep drawing of double-layer metal sheets in a die ofsquare cross-section were investigated through artificial neural network (ANN) modeling. For this purpose,first, the deep drawing of double-layer (Al1200 / ST14) sheets was carried out experimentally. Also, the finiteelement simulation of the process was performed, and the results validated through experimental tests. A setof 46 different experimental data were employed in this paper. The ANN was trained by using a mean squareerror of 10-4. The input parameters, i.e., punch radius, die radius, blank holder force, clearance, and the permutationlayers were set to the network. The surface response method (RSM); was employed to evaluate theresults of the ANN model, and the input parameters of the deep drawing process on the thinning of Al1200and ST14 composite layers were analyzed. The obtained results indicate that the punch edge radius has themost significant influence on the thinning of the Al1200 layer. Increasing the gap between the punch and dieto 1/4 of the sheet thickness, increased the cup wall layers thickness of the Al1200 and ST14 respectively by3.38% and 0.5%. The performance of the ANN model demonstrates that it can estimate the amount of thinningin the composite layers with satisfactory accuracy.

Process planning and management is a decision that uses limited resources to achieve a specific goal. Therefore, production management can be considered as a decision-making process in the field of production issues, planning, organizing, controlling, directing, or motivating human resources. Because in the industry, to ensure product responsiveness, they first act as a single production and workshop and then as mass production. In the present study, a CAD computer model and a fixture were made for the Peugeot 405 brake pump shell. According to the geometric shape of the sample, casting and machining methods are considered in the production of the product. The restraint was designed and made for the final-machining operation. With the help of planning tables and operations sheets, important product specifications, important process specifications, design plans were controlled and reviewed. The results show high compatibility between the production sample and the prototype of Iran Khodro (IKCO) Company. Due to the high compatibility, it can be claimed that the product produced is at a better level in terms of quality, manufacturing and ultimately cost.

In this research, the effect of Diffusion Depth and Heat-Affected Zone (HAZ) in Nanoparticles-Electrode Gas Metal Arc Welding (NE-GMAW) process with carbon dioxide protection on Heat Resistance Steel (SUH 310S) was investigated using the Image Processing (IP) and Simulation software. Welding speed (S), wire feed rate (F) and voltage (V) as effective parameters were considered for experimental tests. The Design of Experiment (DoE) was using the Taguchi method and performed in L11 without experiment replication. According to a Scanning Electron Microscope (SEM) images from the experiments, changes in three effective parameters were obtained. The voltage and wire feed rate had the most significant impact on increasing HAZ and ultimately the diffusion depth due to the increase of heat generated and the creation of a more comprehensive Weld Pool (WP). Experimental 11-samples was used by NI vision IP software to find the diffusion depth and surface zone of the HAZ. Results of the effect parameters in Image Processing and Simulation software showed validation for evaluating changes in HAZ.

The Incremental Sheet metal forming is one of the dieless forming processes. In this process, the ball nose tool runs the predetermined path to form the sheet by applying the local pressure on the sheet. One of the disadvantages of the incremental forming process is the springback phenomenon. In this paper, the effect of parameters on the springback in the two layear sheet Cu / Austenite St produced by the Single Point Incremental Sheet Forming has been investigated. The input parameters of this process include the tool diameter, vertical step, sheet thickness, depth of form, forward velocity, and arrangement of layers of the double layer sheet. Using the finite element simulation via Abaqus software and the Taguchi design of experiments method via Minitab software, the effect of input parameters on springback and forming force has been investigated. Also, the results of the simulation were validated by the empirical test and it was determined that the finite element has an appropriate overlap in extraction of the final results. At the end, the effect of each of the parameters mentioned on the springback and forming force was analyzed. It was determined that the thickness of the sheet had the greatest effect on both springback and forming force.

The cold roll bonding (CRB) is a type of bonding process between similar and/or dissimilar metals that is bonded through plastic deformation via rolling process at room temperature. In addition, the accumulative roll bonding (ARB) process is considered as one of the methods for applying severe plastic deformation (SPD) with the ability to achieve ultra-fine grains (UFG) structure and improved mechanical properties. In this research, a combined method was suggested consisting of ARB and CRB processes in order to fabricate UFG copper strip with simultaneous increase of strength and electrical conductivity. Microstructure, mechanical properties, and electrical conductivity of copper specimen fabricated via combined method and ARB processes were investigated. Field emission scanning electron microscope (FESEM) micrographs showed in the crystalline structure of the specimen fabricated via combined method, a large amount of the UFG with uniform distribution are observable. Also tensile strength and hardness of strips increased with increasing the number of rolling passes. Finally, investigation the electrical conductivity of the specimens by four-point probes test showed electrical conductivity decreases with increasing the number of ARB cycles, while the specimen fabricated via combined method increased simultaneously strength, hardness, and high electrical conductivity.

Equal channel angular rolling (ECAR) is a severe  plastic deformation (SPD) technique which has been used to produce metal sheets with ultra-fine grain structure. In the present work, the relationships between the mechanical properties and microstructure of samples during the ECAR process have been investigated. The Rietveld method was applied to analyze the X-ray diffraction pattern and to determine the microstructural characteristics including the crystallite size, microstrain, and dislocation density. It was observed that the average crystallite size and dislocation density increased by increasing the strain during the ECAR process. The results showed that ECAR is a procedure intended to obtain meaningful structural refinement appearing in a crystallite. It can be justified by using Taylor equation that the mechanical properties are related to the dislocation density. The ECAR process strongly increases the yield strength and microhardness due to an increase in the dislocation density over a wide range of strain.

This paper studies the shear and peel strength of composite AA1050 aluminum and SS 316 steel manufactured by accumulative roll bonding (ARB) process. The ARB samples were tested for shear and peel strength under a single axial tensile test. The layer strength was measured in each sample and the results of the experiments were compared. The results showed that the shear strength of layers was higher than the peel strength; also the microstructure of the sheet after performing 5 cycles of the ARB process was observed. To test the strength of the samples during different passes of the process, tensile tests were carried out; the results indicated a general increase in strength. Further studies on the scanning electron microscope (SEM) images of the fracture sections of the samples showed that by increasing the number of passes, the thickness of the steel layers was less than that in the pass 3 of these layers to tear. In the following, hardness changes along the sheet thickness were studied in successive passes. The results indicated that the pass 2 had an impressive increase in hardness.

Due to rangeland ecosystems management role on nutrient, the present study was conducted to investigate the relationship between soil and plant nutrients in different grazing management and their changes in the Laseoureh rangland, Lorestan Province. For this, the study area was obtained and grazing treatments including grazing, short-term grazing exclosure (one year exclusion) and mid-term grazing exclosure (five years exclusion) was determined by field surveying. Then, the sampling was done by two transects (100m) and 10 plots (1m2) with randomly systematic method. Then sampling was done based on canopy cover percentage in the plots after determination of dominant species. Also, soil sampling was done according to mean root depth in each plot under dominant species. Then, plant and soil properties such as nitrogen, phosphorus and potassium were determined in laboratory. Finally, the data were analyzed using the SPSS 20 software. The statistical processing was conducted by analysis of variance and Tukey-test. The results showed that rangeland species and grazing managements has a significant effect on all nutrient elements (P≤0.05) but the interaction effect of rangeland species and grazing managements significantly (P≤0.05) effect on P. Also, the elements were increased significantly from grazing treatment to one year exclosure and years exclosure while the effect of five years exclosure were increased soil nutrients and short-term exclosure had no significant difference with grazing treatment.

Equal channel angular rolling (ECAR) is a severe plastic deformation (SPD) process in order to achieve ultrafine-grained (UFG) structure. In this paper, the mechanical properties of ECAR process using artificial neural network (ANN) and nonlinear regression have been illustrated. For this purpose, a multilayer perceptron (MLP) based feed-forward ANN has been used to predict the mechanical properties of ECARed Al6061 alloy sheets. Channel oblique angle, number of passes and the route of feeding are considered as ANN inputs and tensile strength, elongation and hardness are considered as the outputs of ANN. In addition, the relationship between input parameters and mechanical properties were extracted separately using nonlinear regression method. Comparing the outputs of models and experimental results shows that models used in this study can estimate the mechanical properties appropriately. Where, the performance of ANN model is better than the correlations to predict mechanical properties. Finally, the developed outputs of trained neural network model are used to analyze the effects of input parameters on tensile strength, elongation and hardness of ECARed Al6061 alloy sheets. The results showed that the ANN model, without highly expensive tests and experiments, is an efficient tool to predict the mechanical properties of ECARed Al6061 sheets.

Friction stir extrusion (FSE) is a process based on the heat generated by friction between die and materials in which a sample is produced through consolidation and extrusion of precursor materials such as metal chips. In this paper, the wire samples produced by friction extrusion of aluminum alloy AA7022 chips are investigated. The samples were extruded at different rotational speeds and extrusion forces, and impacts of these two parameters were studied. At first, structural properties of samples were studied using optical microscopy and scanning electron microscopy (SEM). The result showed that the samples produced at higher rotational speeds and lower forces had a far better surface quality and lower surface crack were seen on them. On the other hand, the temperature of process and grain size were increased with rise of rotational speed. The SEM micrographs showed that by changing rotational speed and extrusion force, the amount of adhesion and sintering between aluminum particles change and by optimizing these parameters can decrease wire’s internal defects and pits. In the following, to study mechanical properties, micro hardness and compression tests were used. The values of hardness and yield stress of samples were decreased with increasing rotational speed and increasing the extrusion force to a certain extent caused increase in yield stress of material.

A large part of organization’s capital is dedicated to working capital and its management has great importance. There is an invert U-shaped relation between working capital management and firm’s financial performance. Regarding to this point that financing conditions may play important role in this relation, the aim of this study is to investigate the impact of financial constraints on the relationship between working capital management and financial performance. It’s a descriptive-correlation study and is based on analysis of panel data. Our sample includes the financial data of 90 listed companies in Tehran Stock Exchange during the period 1386 to 1392. Using cost of external financing as a proxy of financial constraints, it is shown that these financial constraints have meaningful impact on the relationship between working capital management and firm’s financial performance. And the optimal level of working capital is lower for firms that are more constrained financially. Our results suggest that because of cost of recede from it, managers should pay attention to the optimal level of working capital.

In this paper, a new non-isolated SEPIC converter for photovoltaic application is introduced and analyzed. Regarding to low output voltage PV panel and high voltage application of PV systems, a high gain converter is designed. This converter has advantages such as high output voltage gain while keeping the switch voltage stress equal to a regular SEPIC converter, improve the turn-on and turn-off transients of the switch and high efficiency. Also, switching losses and EMI noise are reduced by soft switching method. The MOSFET operates at zero-voltage-switching (ZVS) turn-off and near zero-current-switching (ZCS) turn-on.

The aim of this research was to investigate the effect of emotional intelligence training on communication skills of university students. The methodology was experimental، with two groups of control and test group using pretest and posttest. Statistical population is comprised of 849 female students and 1265 male students in the dormitory of Islamic Azad University، Najafabad Branch in the first semester in 1389-90. From among this group، 255 female and 380 male students were selected as sample because of probable cancellation by participants. Then the sample group was divided into control and test group. Later Queendom Questionnaire of Evaluation of Communication Skills was administered to the sample as the pretest. After that، the test group members were exposed to the independent variable، i. e.، emotional intelligence training period. On the other hand، control group received no intervention. After the end of the training period، all the students were evaluated based on their communication skills using Queendom questionnaire. The results achieved through variance analysis and comparison of the means of the two control and test group revealed that emotional intelligence training caused an increase in the scores of communication skills of students in test group (p<. 05). While، the pre-test and post test scores of students in control group showed no significant difference.