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Showing 19 results for torkaman


Volume 1, Issue 1 (Winter 2023)
Abstract

Nowadays, application of enhanced oil recovery methods has increased; therefore it’s necessary to determine their impacts on environment and human life. So, this research investigates the environmental impacts of conventional enhanced oil recovery methods and new methods such as using electromagnetic waves, ultrasound waves, and nanoparticles. The investigations show that electromagnetic waves and ultrasound can effectively remove many environmental pollutants. Characteristics of the wave and the type of formation determine that these waves have different effects on the formation, and efforts should be made to understand these effects to prevent damage to the formation. Nanoparticles can also reduce the quantity of pollutants in the environment. According to the mechanisms of entrapment of nanoparticles in the porous medium, they may remain in the reservoir and find their way to the underground water over time, so their environmental effects should be considered in the long term. A better knowledge of new methods of increasing oil extraction will lead to the identification and use of more suitable methods with less environmental effects (compared to conventional methods).

 


Volume 2, Issue 2 (6-2013)
Abstract

The melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is one of the most important pests of agricultural products in Iran. In this study, susceptibility of melon aphid that collected from seven regions (Yazd, Varamin, Mohammadshahr, Esfehan, Karaj, Hashtgerd and Ramsar) was compared to pirimicarb and malathion after 24 hours in 2009. Bioassay experiments on adults were carried out by using leaf dipping method on squash (Cucurbita pepo) leaf in different concentrations of insecticides in laboratory conditions (25 ± 0.2 ºC, 60 ± 5%, 16: 8 [L: D] h). Control treatment was dipped in distilled water. Each test was replicated three times. The results showed that LC50 values of malathion for Ramsar, Karaj, Mohammadshahr, Hashtgerd, Varamin, Esfehan, and Yazd populations were 162.99, 159.19, 117.94, 79.96, 38.81, 36.32, and 20.25 ppm, respectively. Also, LC50 values of pirimicarb for Yazd, Mohammadshahr, Kararj, Hashtgerd, Ramsar, Esfehan, and Varamin populations were 1414.16, 1359.34, 1057.62, 970.33, 881.87, 806.14, and 601.98 ppm, respectively. According to results, aphids of Varamin and Yazd populations had the most susceptibility to pirimicarb and malathion, respectively. Also, aphids of Yazd and Ramsar populations had the least susceptibility to pirimicarb and malathion, respectively. Regarding the fact that Yazd and Ramsar populations had the least susceptibility to pirimicarb and malathion, respectively, there is a possibility that melon aphids in these regions are susceptible to other organophosphate and carbamate (similar mode of action) pesticides. Therefore, in the pest management program, careful chemical control measures for melon aphid in these regions is recommended.  

Volume 3, Issue 3 (Number 3 - 2001)
Abstract

The purpose of this study was to compare various direct techniques of measuring attitudes toward risk. The Equally Likely Certainty Equivalent with a Purely Hypothetical Risky prospect (ELCE-PH), The Equally Likely Certainty Equivalent with a Hypothetical but Realistic Risky prospect (ELCE-R) and Probability of Winning Demanded (PWD) models were used to elicit the risk attitude of a sample of farmers. These methods were then compared and evaluated. The criteria employed were (1) sample respondent capability in answering questions, (2) means and corresponding risk attitudes classification and (3) distribution of risk attitudes. According to the first criterion, the results showed PWD technique is the best one. While there are no differences among the three direct techniques on the basis of the second criterion. Also, the findings indicate that respondent education and age, family education, level of hypothetical income and a greater explanation by other people during interview have an influence on respondent capability in answering questions. These characteristics should therefore be considered when choosing the appropriate technique.

Volume 3, Issue 4 (Number 4 - 2001)
Abstract

The most commonly used utility functional forms are reviewed and their properties compared. Then, using data collected from West Azarbaijan province, utility functions are estimated and absolute risk aversion coefficients measured. Exponential and expopower utility functions classified all farmers as risk averse, but quadratic and cubic utility functions classified 75% and 65% of farmers as risk-averse, respectively. Findings in this study indicated that alternative utility functions may classify farmers’ risk attitudes in different ways.

Volume 5, Issue 4 (12-2016)
Abstract

Many environmental and physiological factors affect plant temperature. The objective of this study was to use thermal imagery to investigate robust features for early diagnosis of Botrytis cinerea infection in cut rose flowers under the postharvest application of Methyl Jasmonate (MeJA). Three cases treated with different concentrations of MeJA (0.1, 0.2, and 0.3 µl.l−1), a control (0 µl.l−1 MeJA) and an ethanol-treated case (20 µl.l−1 ethanol) were considered as five treatments in this study. Infrared images of MeJA-treated and non-treated flowers were captured during five consecutive days. Eight days after inoculation, disease severity in all concentrations of MeJA was significantly lower than that of control and ethanol treatments. Maximum temperature difference (MTD) index and median temperature could be used to diagnose the existence and growth of fungal pathogen, at least a day before any significant visual symptoms appear. To identify some robust features for classifying the infected and non-infected flowers, analysis of temperature frequency distribution was implemented. Laplace and normal distributions were considered as the best fitted probability distributions based on the shape of thermal histograms. Parameters of normal and Laplace probability density functions were estimated and the most effective attributes were selected. A radial-basis-function neural network with 60 neurons in the hidden layer was designed to classify and distinguish the infected flowers from the healthy ones. Results showed that the network can classify the infected and non-infected flowers with a 96.4% correct estimation rate.

Volume 7, Issue 1 (Spring 2023)
Abstract

Research subject: Electromagnetic heating is one of the new methods of upgrading and increasing heavy oil extraction. In this method, electromagnetic waves will increase temperature, break heavy compounds, reduce viscosity, and improve and increase oil recovery.
Research approach: In this research, magnetic iron oxide nanoparticles (Fe3O4) were synthesized by the co-precipitation method, and the efficiency of these nanoparticles in the process of electromagnetic heating and heavy oil upgrading was investigated. Also, a comparison was made between the effect of these nanoparticles in the process of electromagnetic heating and activated carbon. In this process, oil samples containing 0.1% of Fe3O4 nanoparticles or activated carbon were irradiated with microwave (frequency 2.54 GHz and power 400 W) for 0 to 8 minutes, and the temperature and viscosity variation were investigated.
Main results: The results showed that microwave radiation increased the temperature of the samples. The temperature of the sample of crude oil, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles increased from ambient temperature to 70, 82, and 90°C, respectively, under wave radiation for 8 minutes. Also, the most significant decrease in viscosity was reported in 4 minutes: the viscosity of crude oil sample, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles under wave irradiation for 4 minutes decreased 295 mP.a to 261, 254, and 223 mP.a, respectively. In other words, the viscosity of the samples under wave irradiation for 4 minutes for crude oil, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles decreased by 11.5, 13.9 and 24.4%, respectively.
 
Javad torkaman, Seyed Ghavamedin Attari ,
Volume 7, Issue 2 (Spring 2022)
Abstract

Aim: Musculoskeletal Disorders (MSDs) are the most common work-related problem in many bakery workers in developing and industrialized countries. This study aimed to assess the rate and ergonomic risk factors of MSDs among traditional bread bakers in Hamadan. 
Method and Materials: This cross-sectional descriptive-analytic study was conducted on 310 traditional bread bakers in Hamadan, Iran. The prevalence of MSDs was assessed using the Nordic Questionnaire (NQ), body map, and Visual Analogue Scale (VAS). Analysis of data was performed in SPSS (version 20) using Chi-square and independent T tests. 
Findings:The Mean and Standard Deviation (M±SD) of work experience, height, weight, Body Mass Index (BMI) and age were respectively, 4±6.82 (Year), 1.6±0.08 (M), 60±12.76 (kg), 24.65±4.70 and 43.5±12.60 (Year). The involved organs in baking consisted of the neck, shoulder, back, waist, elbow, arm, hand, thigh, knee, shin and ankle. The highest prevalence rates of pain in the studied workers referred to the middle back (N=38; %92.68), knees (N=33; %80.49), shoulders (N=13; %30.95), forearms (N=11; %26.19) and wrists (N=11; %26.19) respectively.The prevalence of MSDs correlated with BMI and work experience significantly (P ≤0.05).
Conclusion: As, this study revealed that the rate of musculoskeletal disorders in the different body regions of bread bakers were high, properinterventional preventive management are strongly recommended to be designed and impleneted to eliminate the disorders among this target group.

Maryam Nazari, Sahar Boozari, Giti torkaman, Mohammad Ali Sanjari,
Volume 9, Issue 4 (Fall 2024)
Abstract

Aim: Since physical performance is one of the important parts of health, proper evaluation of people's performance is so much important, as it helps rehabilitation team to choose the best methods to improve performance. Involving all the muscles and joints, jumping is an activity used to evaluate performance. The accelerometer is an instrument that has recently been considered in the field of performance evaluation for some reasons like being economical, accessible, and the ability to replace expensive tools in the health system. This article reviews some studies that use accelerometer to evaluate performance of the neuromuscular system.
Method and Materials: Keywords were searched in PubMed, Scopus, and Google Scholar databases to find studies on the reliability and validity of accelerometers in jump performance from 2010 to January 2024.
Findings: In calculating most variables including jump height, flight time, contact time, stiffness, force, power, and reactive strength index of countermovement, squat, and drop jumps, studies have revealed high validity and reliability for this device. In calculating peak power and peak velocity, accelerometer has low validity and reliability, though.
Conclusion: Under the ground of the fact that accelerometer is a valid and reliable instrument in evaluating most jump performance variables, it may be counted as a useful instrument. Rehabilitation team, physical medicine, and sports medicine specialists would use this device to evaluate musculoskeletal system performance; Therefore, they will be able to adjust, modify, and finally improve the rehabilitation program for patients or athletes and thus promote health in society.
 

Volume 10, Issue 4 (3-2021)
Abstract

The first and second policy of the Policies of Resistance Economy point to the special importance of the performance of knowledge-based companies as a basis for utilizing the capacity of human capital and entrepreneurship development in the country.The purpose of this research was to investigate the effect of internal marketing on the performance of knowledge-based companies located in Hamadan Science and Technology Park with the role of market orientation. The research was an applied and a field research. The statistical population consisted of all knowledge-based company's employees located in Hamadan Science and Technology Park. The sample size was 195 people. The research variables were measured using a standard questionnaire. The results of structural equation analysis with PLS software showed that internal marketing directly influenced firm performance by 14%, internal marketing by 81% influenced market orientation and market orientation influenced firm performance by 71%. In general, it can be concluded that internal marketing has a 57% indirect effect on firm performance with a mediating role of market orientation. Therefore, corporate executives should be aware that improving the performance of companies depends on attention to the employees and the company's customers by improving internal marketing and market orientation. The contribution of the present research confirms the importance of linking human resource management, as internal marketing, with external marketing, as focusing on market orientation, in the success of knowledge-based companies.

Volume 13, Issue 1 (1-2010)
Abstract

Objective: To investigate the friction of rabbit’s knee joint with designed pendulum friction tester to diagnose and evaluate different pathological and therapeutic conditions following haemarthrosis, osteoarthritis, and other joint disorders. Materials and Methods: Friction coefficient of 10 adult male Albino rabbit’s joint (5 right and 5 left knees) weighted 1.59 ± 0.27 Kg, after designing and compiling the instrument and its processing software in the Physiotherapy department of Tarbiat Modares University were measured. Maximaum pendulum rotation, number of oscillations to reach equilibrium, coefficient of friction with Stanton’s equation, exponential and linear curve fitting, average logarithmic and linear decrement methods were measured. Results: Maximum rotation after pendulum releasing in the left joints were higher than the right ones, P<0.001. Number of oscillations to reach equilibrium in the left knees were also greater than the right knees, P=0.005. All different friction estimation methods had the same results and showed greater friction in the right in comparison to the left side. Conclusion: The pattern of the joints amplitude decay did not have a linear behaviour and the rabbit’s knee joint coefficient of friction with nonlinear estimations was less than linear ones. The findings revealed that selecting a separate control group in such investigation is essential and the contralateral limb could not be considered as control group. Pendulum friction tester has the capability of evaluating changes in coefficient of friction after application of different therapeutic methods. These changes have important role in diagnosis, evaluation of joint diseases and developing techniques for treating those pathologies.

Volume 13, Issue 1 (1-2010)
Abstract

Objective: To classify different types of acute leukemia based on cooperative game theory and Shapley value. Materials and Methods: In this study, patients data were collected from Flow Cytometry tests of the Iran Blood Transfusion Organization (IBTO) have been used. 304 different diagnosed samples in 8 classes of acute leukemia were investigated. Samples were initially in numerical format. In the next stage, we transformed them into Boolean format according to the defined threshold. Then, weights were assigned to these samples based on cooperative game theory and Shapley value. In this regard, different samples of acute leukemia were separated and classified (Learning Phase). In the diagnosis phase, using similarity measures, the similarities between new under study and the training samples were assessed and the type of under study leukemia were detected (Diagnosis phase). Results: The accuracy rate of the classification method based on the cooperative game theory for leukemia was 96.3% which indicates that the proposed method has a considerable precision rate to classify the different kind of classes. In order to find the validity and efficiency of the proposed method, the results were compared with neural network, which is one of the useful learning algorithms. The accuracy rate of the classification method based on Radial Basis Function method (RBF) was 91.80%. Conclusion: Considering the data, the proposed method gave very hopeful results for acute leukemia classification. In this regard, it can assist hematologists and physicians in reasonable and accurate diagnosis of the kind of leukemia, to make more suitable decisions.

Volume 13, Issue 2 (summer 2013 2013)
Abstract

The statistical data of Tehran Province shows that the ratios of output and employment of service sector to total provincial output and employment are 57 and 63 percent in 2001, respectively. The aim of this article is to quantitatively explain the structure of service –based economy of province, using Input-Output Model and intersectional linkages by Eigen Vector method. So, the main question in this research is that can the usage of Eigen vector method rather than traditional methods like Chenery-Watanabe and Rasmussen methods evaluate more precisely the importance of provincial economic sectors on the basis of intermediate viability in the production process?     For this purpose, first the Input-Output Table of “Tehran Province” for 2001 was estimated by AFLQ method, and then the importance of provincial economic sectors was measured in terms of forward and backward linkages by Chenery-Watanabe, Rasmussen and Eigen vector methods.     The results show that Eigen Vector Method can explain the importance of economic sectors of province on the basis of intermediate viability in the production process, in such a way that four key sectors are of dominant shares in industrial activities which their average share of demand out of total output is 45.5 percent, but ratios for 71 economic and service sectors are 76 percent and 84 percent, respectively. In general, results show that the nature of service sector in Tehran province is different from the services in modern economies. The main reason is that the service sector in Tehran is the consuming rather than producing sector.

Volume 13, Issue 2 (summer 2013 2013)
Abstract

There have been few studies working on effects of financial repression policies on Iran’s economic growth. Considering the huge share of agricultural sector, we have been trying to fill this gap by the help of time series data from 1962 to 2007 on agricultural GDP, unproductive government expenditure, human capital, industrial price index, political instability, and financial repression measures. Results show that controlling the bank reserve requirement ratio as a proxy for financial repression has negative effect on economic growth of agricultural sector. This indicates that reducing controls on this parameter will help government to achieve higher rate of growth.

Volume 15, Issue 7 (9-2015)
Abstract

Laser processes are widely used for surface properties improvement of parts and components. Laser cladding, using laser as heat source, is an innovative method that can be used for improving surface properties. In this investigation, preplaced technique of laser cladding process of WC powder on Inconel 718 using pulsed Nd:YAG laser is studied. A number of parameters affect the energy density in the process, ultimately affecting the clad quality and geometry. In this study, laser average power, pulse width, focal distance, scanning speed and pre- placement factors are input parameters, while clad dilution, fusion depth, porosity and number of cracks are outputs. It is observed that hard phases are formed on Inconel surface in-situ by laser beam radiation and small changes are made in the substrate properties in a limited zone. Experimental results reveal that energy density of the laser beam is the most important factor affecting the number of cracks in laser cladding process. Also, dilution and porosity are highly affected by laser average power. Furthermore, in multi-pass laser cladding process, 50% overlap between adjacent passes has good results. Experimental results show that by concise arrangement of input parameters, one can achieve to an optimum clad layer. Thus, laser cladding process can efficiently supersede other conventional methods.

Volume 17, Issue 6 (11-2015)
Abstract

Cyclotides are small disulfide-rich proteins that have the unusual feature of a cyclic backbone. Cyclotides have a range of interesting biological activities and are found in a variety of tropical plants from the Rubiaceae, Violaceae, Cucurbitaceae and Fabaceae families. We have cloned and characterized cyclotides in Viola modesta, a Viola species native to western Asia, which was collected from the Kurdistan Province of Iran. Fifteen cyclotide sequences were obtained using homology based PCR strategy. Sequence analysis showed that 14 of them had continued open reading frames and showed high level of similarity to cyclotide genes from other species of the Violaceae. After analyzing the full endoplasmic reticulum signals of V. modesta cyclotides, two conserved sequences, AAFALPA and ATAFALP, were detected. Analysis of isolated cyclotide sequences showed that they all belonged to bracelet family and were separated into two subclasses. Phylogenetic analysis of cyclotide genes from V. modesta and other Viola species revealed that most V. modesta genes showed close relationship with their homologs from the Violaceae, while the V. modesta genes formed two separate clades. Transcription analysis by semi-quantitative RT-PCR revealed that Vmcyc1 and Vmcyc7 were differentially expressed in all tested tissues including roots, stems, leaves, flowers, seeds, peduncles, and capsules with the highest transcript level in the capsules.

Volume 18, Issue 9 (12-2018)
Abstract

Microwave-induced thermo-acoustic imaging (TAI) is an imaging technique with a great potential in detecting breast cancer at early stages. This technique combines the advantages of both microwave and ultrasound imaging. In this technique, image construction is based on the acoustic waves which are produced in the tissue due to irradiation of microwave pulses on it. Due to multi-physics nature of this phenomenon, the capability and feasibility of a numerical simulation method which can solve this problem consistently, investigated with performing a two dimensional simulation of TAI. In this simulation, a biological tissue including a tumor is considered in a rectangular duct (waveguide) under irradiation of pulsed 2.45 GHz microwave source. The generated heat in the biological tissue due to electromagnetic waves irradiation and the corresponding pressure gradient in the tissue due to the temperature variations are evaluated. It is then studied for different power levels of microwave sources for identifying required power level for producing thermo-acoustic signals. Simulation results show a minuscule rise in temperature as a result of the absorption of pulsed microwave energy, for example, 0.004743°C temperature increment in the center of the tumor, due to excitation pulse of 1000 W, 200 μs. This small temperature variation in tumor, produce several kPa of pressure variations, 0.02759 kPa pressure difference at the interface of tumor and breast tissue. This pressure variation will produce acoustic signals, which can be detected with array of transducers and used for construction of image.


Volume 19, Issue 124 (June 2022)
Abstract

 
Celiac disease is the most common disease caused by gluten consumption. Gluten protein, is the most important compound in creating tissue and contains components of the formulation of baking products. This protein causes allergies in people with celiac disease, and the only way to treat the disease is to eat a gluten-free diet for a lifetime.Therefore, the use of appropriate alternatives to gluten in the preparation of this category of products is essential. Therefore, the aim of this study was to investigate the effect of rice bran protein concentrate in the amount of  0.75. , 1.5, 2.25, 3 % as a gluten substitute for sponge cake. Based on the results, it was found that the viscosity of the product dough has increased compared to the control sample and the addition of rice bran protein has a significant effect on the density of sponge cake dough. Also, increasing the protein concentrate in mentioned amounts caused a significant increase in the moisture and specific volume of the cake. The results of tissue stiffness analysis of the samples showed that there is a significant difference compared to the control sample. According to the results, the highest score was given to the sample containing 2.25 rice bran protein and the selected treatment was T3 treatment.


Volume 23, Issue 5 (Winter 2021)
Abstract

Introduction: Osteoarthritis is the most common type of arthritis and is one of the most common causes of pain and disability in adults. In the present study we investigated the level of inflammatory cytokines IL-1β and TNF-α and the amount of joint friction after non-traumatic model of knee osteoarthrosis in guinea pig.
Materials & Methods: Twenty-four matured albino male Dunkin-Hartley guinea pigs were assigned randomly into two groups; osteoarthrosis (OA) and control (n=12 in each group). The non-traumatic OA was induced by intra-articular injection of mono iodoacetate (MIA, 3 mg/kg) in the knee joint. Joint circumstance and weight of subjects were measured initially and after thirty days of MIA injection. After scarifying the animals on day 30, the level of IL-1β and TNF-α in synovial membrane and knee joint friction were measured. Control group received no intervention and all evaluations were performed on the normal knee joint.
Results: The induction of OA caused a significant increase in the joint circumstance compared to control group (P<0.05). 30 days after induced OA, the knee joint friction in flexion and extension movement was significantly increased compared to control group.  In OA group, the level of IL-1β and TNF-α showed a significant increase compared to control group (P<0.05). There was a positive correlation between IL-1β, TNF-α and knee joint friction (P<0.01).
Discussion: Non-traumatic osteoarthritis may increase the expression of inflammatory cytokines and joint friction, which in this condition the joint movement can aggravate cartilage damage.



Volume 31, Issue 2 (Summer 2024)
Abstract

   Change in the family in Iran has strengthened the discourse of disintegration. In this article examines the phenomenological study of the conceptual space of the family and its status through of actors. The research has been done with a qualitative approach and relying on the live people from different family models. The study population is a purposeful sample of 29 residents of Tehran at 2017, which includes the normative family and its alternatives. Necessary data were collected by interview technique and analyzed and interpreted by content analysis method. Research has shown that in the mental space of actors, the family model is not obsolete but is facing changes and has changed from function emotional and from rigid structure to fluid and process and jointly with the main the main themes of sexual satisfaction, support, commitment, love and Sustainability is built. Strategies show that the family and its alternatives are moving towards the nuclear family model. Also, an important feature of the family and its distinguishing feature from the Western model is maintaining family relations, navigating the kinship system, and maintaining its emotional and economic support. Thus, the dependent nuclear family is the dominant mode in the conceptual space of the family.


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