Search published articles
Showing 49 results for Fani
Volume 20, Issue 144 (February 2024)
Abstract
Oxidation in living organs causes dangerous diseases, including cancer, and in food, it causes spoilage and heavy economic losses. Synthetic antioxidants have adverse and dangerous effects on human health, therefore identifying natural antioxidant compounds is one of the main needs of the food industry. In fish processing industries, about 50-70% of fish, which are potential sources of valuable nutritional compounds such as essential amino acids, are produced as waste. Therefore, finding a way to optimally use these wastes and produce healthy compounds with high added value such as bioactive peptides has great importance. In this research, the effect of hydrolysis conditions (time: 30-300 min and enzyme concentration 0.5-3 %) and type of protease (alcalase and pancreatin) on the degree of hydrolysis and antioxidant properties (DPPH radical scavenging activity, Fe chelating activity, nitric oxide radical inhibition, total antioxidant capacity and Fe reducing power) of protein hydrolysate from skipjack viscera was investigated using the response surface methodology. The results showed that the optimum conditions for achieving the most antioxidant properties with alcalase and pancreatin were: hydrolysis time of 146.9 and 171.67 minutes and enzyme concentration of 1.94 and 2.17%; in these conditions, the degree of hydrolysis of the produced protein hydrolysates was 25.12% and 20.35%, respectively. Comparing the antioxidant properties of hydrolysates produced by both proteases showed that the alcalase enzyme led to the production of protein hydrolysates with stronger antioxidant properties than pancreatin. Therefore, it can be concluded that the protein hydrolysate of the skipjack fish viscera using alcalase enzyme as a healthy and value-added product can be used in the production of functional products and health supplements.
Volume 21, Issue 2 (5-2021)
Abstract
There are some Innovative methods to control the damage caused by seismic loads, and one of them is to concentrate the damages on the designated region or members. The reduced beam section connection, also known as the dogbone connection, is a promising option for improving the ductility of steel beam to column moment connections, especially in high-risk regions. By symmetrically trimming the width of the beam flanges over a discreet length in the vicinity of the beam ends, a ductile fuse can be created to accommodate the inelasticity that is required for seismic energy dissipation while is not only protecting the beam to column connection but also prevent causing the catastrophic and progressive collapse of the structure. This paperchr('39')s emphasis is the performance of the steel portal frame with RBS connections based on detail provided by AISC specification. The concentration of plastic deformations in the RBS region under cyclic load causes intensified stresses that accumulate damage. The prediction of ductile damage and fracture is one of the most important challenges in many engineering applications. Damages in a structure are caused by material degradation due to initiation, growth, and coalescence of microcracks/voids in a real-life material element from monotonic, cyclic/fatigue, or dynamic/explosive impact loading. The damage evolution law describes the rate of degradation of the material stiffness once the corresponding initiation criterion has been reached. In this study, the ductile damage model presented for steel is used. Damage Initiation parameters and damage evolution rules were obtained based on standard tensile test from literature and software procedure analysis. A coupon model has been established based on the standard tensile test to evaluate the ductile damage model. Also, to validate the steel portal frame with the RBS connection model two-step has been considered. In the first step, the global response of the steel moment frame was validated based on Wakabayashichr('39')s test. Also validation of the RBS connection model was checked based on Pachoumis experiments in the next step. Then, according to AISC 360 steel and AISC 341 steel, a steel moment frame design with RBS connection was designed. By selecting and extracting a single-span portal frame, the effect of considering damage was investigated by finite element analysis. Initial geometrical imperfections were determined using the AISC 360 Recommendation for out-of-plumbness, out-of-straightness, and localized geometrical defects. The cyclic displacement amplitude followed the loading protocol in the ATC-24. The study results show in the elastic region the behavior of the frame remains unchanged before the frame reaches the high amplitude cycle. But gradually, with increasing cycles, the size of the hysteresis loop and ultimate resistance became smaller. Thereby, if the aim is to focus on the load levels that lead to large localized plastic deformations, it is critical to consider the damage parameters to improve the reliability of the results. Measurement of the area below the graph in the last loading cycle shows that the dissipated energy in the two cases without vertical load and with a vertical load on the columns is decreased by 2.6% and 4.1%, respectively. The continued deterioration of the RBS region due to damage spreads leads to complete frame failure, which is not properly predicted when damage parameters are ignored.
Volume 22, Issue 1 (1-2020)
Abstract
Ghee, a nutritional dairy product in Iranian culture, can be easily produced on a small scale. This study was undertaken to analyze fatty acids and volatile compounds of collected ghee samples from different ghee production sites of Iran (Ilam, Kermanshah and Hamedan) using HeadSpace Solid Phase MicroExtraction (HS-SPME) technique. According to the results, palmitic and oleic acids were the dominant fatty acids in all the samples investigated. Further, it might be concluded that compounds such as dodecane, acetone, butyric acid, hexanoic acid, 2-pentanone, 2-heptanone, and 2-undecanone, which are present and might have accumulated as the results of oxidative, hydrolytic, or microbial activities, contribute to the flavor of ghee. Lactones, which are produced at high temperatures, were not collected in any sample except the Hamedan sample (< 1%). Low thermal processing in the ghee production prevented the formation of off-flavor volatile compounds. The qualitative and quantitative parameters determined in this study might be useful in assessing the quality of the ghee and may help the industry to improve its commercial production.
Volume 23, Issue 1 (1-2021)
Abstract
Spatially explicit estimates of aboveground biomass over large area are necessary for natural resources managers. This study examined aboveground biomass and carbon stock of the wild pistachio (Pistacia atlantica) based on individual tree crown detection and allometric development in the arid woodlands using high-resolution satellite images of GeoEye-1 in a reserved forest area of Wild Pistachio trees in the South Khorasan Province, East of Iran. Biomass of sampled trees was determined using field sampling and experimental tests. In addition, the biomass of stems was determined using volume and density. The allometric biomass and carbon stock equations of Wild Pistachio trees were developed based on crown area, diameter at breast height (1.3 m), and height of trees. The trees crowns were detected and delineated on the GeoEye-1 images, using local maxima filters, and region growing segmentation algorithms, respectively. In addition, a morphological watershed transformation method was applied to split the connected and overlapped tree crowns. Performing algorithms was assessed using the measured field crown of sample trees by precision, recall, and overall accuracy indices. The biomass and carbon stock of trees of the study area were estimated using delineated crown area and the developed allometric equations. The results showed that the equation that used crown area could explain more than 80% of the remarked variation in biomass and carbon stock. In addition, the crown detection method results showed that overall detection rate and the quality of crown boundaries were acceptable. In conclusion, the study confirmed that combining the allometric equations with crown information from high-resolution images could contribute to the explicit mapping of biomass and carbon stock of wild pistachio trees in the arid woodlands.
Volume 24, Issue 1 (Spring 2020)
Abstract
Introduction
In Iran,time is limited and it is always too late to modify management attitudes in the fields of environment. On the one hand, the relevant agencies do not even know their priorities separately or are unaware relationship of their priorities with other agencies, while at the macro level, they are unaware of the province's development plan. So, important drivers in the field of environment are the first and most important steps in guiding scenarios of proper management.
Methodology
First, a list of effective drivers of environmental management in the South Khorasan province was collected from some specialist and experts using Delphi, followed by two-dimensional matrices containing quantitative matrices to quantify the driver’s relationships and interpretations. The axes of influence and dependenceare were used. Therefore, according to the position of each driver with these two criteria in the matrix, five types of drivers are defined. Drivers screening based on the degree of influence and dependence of other drivers as effective , key and independent drivers in the field of environmental management in South Khorasan province were studied. The method used was MicMac Structural Analysis, which was used by academic experts and related executives. In so doing, the team created a common language which will served them as the process continued. In most cases, it also allowed the team to redefine certain variables and refine the analysis of the system. Lastly, experience shows that the ideal percentage of the matrix to be filled-in is around 20%.
Comparing the rankings of the variables from the various classifications (direct, indirect and potential) is a rich source of information. It allows the team to confirm the importance of certain variables as well as to reveal those variables which play a dominant role in the system, and which would have remained undetected if they had only been compared directly. The information obtained by influence and dependence of each of the variables can be displayed in two-dimensional diagrams containing the vertical (affective) and horizontal (affective) axes. This method can identify the most effective drivers in the system and study the different roles played by these drivers (Godet & Durance, 2011).
Results and discussion
By aggregating and analyzing the views of a panel of experts in the field who know the topic in MicMac 39 software, drivers were identified as key, effective, effective and dependence drivers. The comments were considered as MicMac inputs, with a filling rate of 23.86% including 153 one (weak influence), 113 two (moderate influence), 89 three (strong influence) and 8 to P (possible influence). The sum of direct and indirect and probable influence of drivers were estimated to be 3007, 2805, 2135, 1938 and 1572, respectively. This matrix has 100% stability with two replications which shows high validity of the questionnaire and its answers. The directinfluence (a) and indirect (b) influence of the drivers on each other are shown in Fig. 1.
Driver 5 (D5: creating environmental law enforcement and warranties) and D1 (co-operation between related agencies to prevent any re-work) in four ways are among the most effective and determining factors. In the next step, the influence of the drivers of the free flow of information and sharing the results of studies of all environmental-related organizations to public or academic expertise (D33), changing the real attitude of decision-makers in embracing intellectual physical potential, and creative indigenous peoples of the region (D29) and the environmental agency's correct placement in decision making (before doing the project and any action not after it is finalized or completed!) (D6) were more influence drivers respectively.
Given that the distribution of drivers is in the axis of influence and dependency as L shape, the system under study is balanced and it is possible to make planning for such a system (Arcade et al., 1999; Erfani and Mircheraghkhani, 2018)
Conclusion
Five main and key drivers of the system under study were identified, the first two of which relate to political and institutional domains that are in line with Erfani and Mircheraghkhani’s (2018) study. In this study, monitoring of nine identified response drivers is the main indicator for revealing the province’s environmental management status, which is recommended for future studies. These indicators can explain the environmental status of the province and can be considered as a criterion for determining the actual performance and efficiency of the agencies. It is also recommended to continue the present study and to complete four more steps from the LIPSOR School to identify conflicts of interest between relevant stakeholders, scenarios building and predict the future.
Each year, the performance statistics of the agencies are presented based on the indicators set by the agencies themselves and the overhead agencies, and they are more likely to be defined in a way that may not adequately represent the agencies’ performance, and thus make the agencies less judgmental to fall. For example, the index of mountain tenure has clearly increased over the last few years. Combating mountain tenure alone does not indicate management efficiency, but rather the absence of mountain tenure and the return of shifting areas given to conditions close to the baseline status is effective either. Therefore, change in decision makers' attitudes (D6) and efforts in problem solving have been introduced as one of the key drivers in this study (Fig. 1).
In Iran,time is limited and it is always too late to modify management attitudes in the fields of environment. On the one hand, the relevant agencies do not even know their priorities separately or are unaware relationship of their priorities with other agencies, while at the macro level, they are unaware of the province's development plan. So, important drivers in the field of environment are the first and most important steps in guiding scenarios of proper management.
Methodology
First, a list of effective drivers of environmental management in the South Khorasan province was collected from some specialist and experts using Delphi, followed by two-dimensional matrices containing quantitative matrices to quantify the driver’s relationships and interpretations. The axes of influence and dependence
Comparing the rankings of the variables from the various classifications (direct, indirect and potential) is a rich source of information. It allows the team to confirm the importance of certain variables as well as to reveal those variables which play a dominant role in the system, and which would have remained undetected if they had only been compared directly. The information obtained by influence and dependence of each of the variables can be displayed in two-dimensional diagrams containing the vertical (affective) and horizontal (affective) axes. This method can identify the most effective drivers in the system and study the different roles played by these drivers (Godet & Durance, 2011).
Results and discussion
By aggregating and analyzing the views of a panel of experts in the field who know the topic in MicMac 39 software, drivers were identified as key, effective, effective and dependence drivers. The comments were considered as MicMac inputs, with a filling rate of 23.86% including 153 one (weak influence), 113 two (moderate influence), 89 three (strong influence) and 8 to P (possible influence). The sum of direct and indirect and probable influence of drivers were estimated to be 3007, 2805, 2135, 1938 and 1572, respectively. This matrix has 100% stability with two replications which shows high validity of the questionnaire and its answers. The direct
Driver 5 (D5: creating environmental law enforcement and warranties) and D1 (co-operation between related agencies to prevent any re-work) in four ways are among the most effective and determining factors. In the next step, the influence of the drivers of the free flow of information and sharing the results of studies of all environmental-related organizations to public or academic expertise (D33), changing the real attitude of decision-makers in embracing intellectual physical potential, and creative indigenous peoples of the region (D29) and the environmental agency's correct placement in decision making (before doing the project and any action not after it is finalized or completed!) (D6) were more influence drivers respectively.
Given that the distribution of drivers is in the axis of influence and dependency as L shape, the system under study is balanced and it is possible to make planning for such a system (Arcade et al., 1999; Erfani and Mircheraghkhani, 2018)
Conclusion
Five main and key drivers of the system under study were identified, the first two of which relate to political and institutional domains that are in line with Erfani and Mircheraghkhani’s (2018) study. In this study, monitoring of nine identified response drivers is the main indicator for revealing the province’s environmental management status, which is recommended for future studies. These indicators can explain the environmental status of the province and can be considered as a criterion for determining the actual performance and efficiency of the agencies. It is also recommended to continue the present study and to complete four more steps from the LIPSOR School to identify conflicts of interest between relevant stakeholders, scenarios building and predict the future.
Each year, the performance statistics of the agencies are presented based on the indicators set by the agencies themselves and the overhead agencies, and they are more likely to be defined in a way that may not adequately represent the agencies’ performance, and thus make the agencies less judgmental to fall. For example, the index of mountain tenure has clearly increased over the last few years. Combating mountain tenure alone does not indicate management efficiency, but rather the absence of mountain tenure and the return of shifting areas given to conditions close to the baseline status is effective either. Therefore, change in decision makers' attitudes (D6) and efforts in problem solving have been introduced as one of the key drivers in this study (Fig. 1).
Volume 24, Issue 4 (April 2024)
Abstract
Waste heat dissipation from spacecraft subsystems is crucial due to spatial limitations (no convective heat transfer, limited electrical power, lightweight, and high reliability). Radiators are often responsible for collecting and dissipating this waste heat into cold space. Panel radiators are widely used in various satellites, including scientific, communication, and remote sensing satellites. In scientific satellites, panel radiators are used to dissipate heat generated by scientific instruments such as cameras and spectrometers. In communication satellites, panel radiators are used to dissipate heat generated by power amplifiers. In remote sensing satellites, panel radiators are used to dissipate heat generated by sensors and processors. High efficiency, light weight, and high reliability are the advantages of using this equipment. The main challenge in using it is to provide sufficient heat dissipation area and uniformity of the surface temperature when radiating waste heat to the cold environment (space). The use of heat pipes in the panel radiator structure provides this uniformity. A heat pipe radiator consists of a sandwich panel with an embedded network of heat pipes. Increasing the number of heat pipes reduces the temperature gradient across the radiator surface but increases the radiator weight. Due to the importance of equipment lightness in space systems, optimization of the number of pipes and their geometric arrangement in the radiator should be such that maximum temperature uniformity on the surface and minimum radiator weight are achieved. The objective of this research is to optimize the performance of a radiator (maximum temperature uniformity on the surface) to achieve minimum weight while considering the weight and size constraints imposed by the system designer as requirements. Initially, a mathematical model is developed and solved numerically, and the effect of design parameters on the performance of a panel radiator, including face and core thickness, spacing between heat pipes, mass, and surface area, is comprehensively investigated. Based on the simulation results, considering the weight limitations and existing face and core thicknesses, the maximum allowable spacing between heat pipes is calculated to achieve maximum efficiency of the panel radiator. A network of heat pipes with this characteristic was produced and used in the panel sandwich. The results obtained from testing the manufactured panel radiator were compared with the design efficiency to validate the model. Based on the experimental results, an efficiency of 89% was obtained at a root temperature of 39°C. The error of this efficiency with the efficiency calculated from the theory is about 3%.
Volume 25, Issue 2 (Spring 2022)
Abstract
Introduction: Emerging evidence suggests that lipoproteins levels are associated with cognitive health. This study examines the relationship between lipoprotein levels and cognitive performance in middle-aged and young adults. It addresses the impact of abnormal lipid levels and hypercholesterolemia on cognitive impairment.
Methods: We performed a cross-sectional study involving 123 healthy security guards aging 20- 60 years old. Lipid profiles included total cholesterol (TC), low-density lipoprotein, high-density lipoprotein (HDL) and triglyceride (TG) levels were measured in serum. EEG recording was used to obtain the cognitive indicators of attention, memory, salience, language, mood and executive function. Spearman correlation analysis was used to determine the correlation between lipoproteins and cognitive indices.
Results: A significant relationship with executive function was found for TC (r = -0.2944, p = 0.0202) and LDL (r = -0.3687, p = 0.0032). Additionally, a significant relationship was found between attention and serum HDL levels (r = -0.1987, p = 0.0296). In middle-aged security guards, there was a significant correlation between attention and TC (r = -0.4338, p = 0.0187) and LDL (r = -0.3909, p = 0.0360). Also, there was a significant correlation between executive function and TC (r = -0.5475, p = 0.0368) as well as LDL (r = -0.6709, p = 0.0077).
Conclusion: Our findings suggest that executive function and attention are key cognitive indices significantly linked to lipoproteins. In the middle-age group, higher TC and LDL levels correlated with lower cognitive scores compared to the general population, indicating a potential role of lipoprotein factors in cognition.
Methods: We performed a cross-sectional study involving 123 healthy security guards aging 20- 60 years old. Lipid profiles included total cholesterol (TC), low-density lipoprotein, high-density lipoprotein (HDL) and triglyceride (TG) levels were measured in serum. EEG recording was used to obtain the cognitive indicators of attention, memory, salience, language, mood and executive function. Spearman correlation analysis was used to determine the correlation between lipoproteins and cognitive indices.
Results: A significant relationship with executive function was found for TC (r = -0.2944, p = 0.0202) and LDL (r = -0.3687, p = 0.0032). Additionally, a significant relationship was found between attention and serum HDL levels (r = -0.1987, p = 0.0296). In middle-aged security guards, there was a significant correlation between attention and TC (r = -0.4338, p = 0.0187) and LDL (r = -0.3909, p = 0.0360). Also, there was a significant correlation between executive function and TC (r = -0.5475, p = 0.0368) as well as LDL (r = -0.6709, p = 0.0077).
Conclusion: Our findings suggest that executive function and attention are key cognitive indices significantly linked to lipoproteins. In the middle-age group, higher TC and LDL levels correlated with lower cognitive scores compared to the general population, indicating a potential role of lipoprotein factors in cognition.
Volume 26, Issue 3 (Fall 2022)
Abstract
South Khorasan Province has gone through rapid industrialization and urbanization processes in the last decades and is under increasing pressure from various environmental challenges such as water scarcity and intensification of pollution and ecosystem degradation. Therefore, the purpose of this study is to develop scenarios for the future state of the environment of South Khorasan province using LIPSOR, the French school of scenario building, and by the application of simple interaction matrix models and morphological analysis to systematically help the environmental management orientations. For this purpose, key variables were first introduced as the main drivers or actors shaping the future. SMIC PROB-EXPERT software package was used to explain the initial scenarios of the future environmental situation of the province. Then a set of scenarios including the most probable scenarios were identified using MORPHOL software. Also, due to a large number of scenarios, the framework of general scenarios was used to describe different axes and conditions. The results of the study of the five main drivers in the SMIC model led to the extraction of 10 initial scenarios. Then, morphological analysis with the MORPHOL model with three political, institutional-executive, and cultural domains produced 3125 possible and probable scenarios, each of which shows the probability of D5/D6/D1/D33/D29 propulsion, respectively. Finally, the analysis of 50 possible scenarios showed that scenario 11111 is the most probable scenario (276.41%), and scenarios 11112, 11113, and 21111 are with probabilities of 184.28, 122.85, and 115.17, respectively, which are five of its constituent variables mainly indicating the probability of occurrence of low (1) to moderate (2 and 3) in the scenarios. In general, the future environmental situation of South Khorasan province is in the situation of the third quarter called lack of discretion in the environment. To change the future and move towards a better future, paying attention to each of the influential variables will be the way forward and can be directed towards a quarter of the framework with at least one flourishing axis.
Volume 27, Issue 1 (Spring 2023)
Abstract
Among the various processes of land degradation, soil erosion is known as a major environmental problem that causes the loss of topsoil and nutrients, reduces fertility, and thus decreases in crop yield. Evaluating and preparing a risk map and estimating the lost economic value due to the loss of soil nutrients can provide the basis for rational planning to prevent and control wind erosion. The aim of this research is to estimate the economic consequences of wind erosion in the Hamoon wetland, which is considered as one of the centers of dust production in the Sistan plain. This research has been done in two stages; first, using the IRIFR model, which is an experimental model to estimate the intensity of wind erosion, an attempt has been made to investigate the erosion intensity, prepare a map of erosion classes (danger), as well as determine the amount of annual sediment production in Hamoon wetland. In the second stage and the economic discussion on the topic, in two parts and using the information obtained from the first stage, using two methods of risk assessment and alternative cost, to prepare a risk map, and the economic value lost due to the loss of the main nutritional elements of the soil action has been taken due to wind erosion in the proposed region. The findings show that Hamoon lagoon has five risk classes in which, the low-risk class has the largest area with 41.15 percent. In terms of economics, from the point of view of the risk map, the largest area of the wetland includes the intensity of risk with 59.93 percent in the very low class, 32.68 percent in the very high class, and 7.36 percent in other classes. The amount of lost economic value of the main soil elements due to wind erosion in the mentioned wetland is estimated to be 994 billion Rials.