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Urban space is combination of two parts including form and meaning. The signs in the urban space together with its codes form the part of urban space meaning. Signs are the part of the visual media which are presented for the citizens, So the citizens discover code's meaning by decoding of internal concept and are influenced by it. The question is that the signs which are presented to citizens as a visual media what relations they have with national identity elements? Urban signs can have meanings of national identity elements into their codes. It is notable that prominence of some elements and factors rather than others has role in formation, reinforcement and representation of national identity. Therefore in this research an attempt has been made to evaluation of relations between the signs meaning in urban space and elements of national identity factors in the 6th, mural district of Tehran as a case study by using of qualitative analysis and the basics semiotics. The results of this research in the 6th district of Tehran indicated that urban signs are influenced by national identity factors and they have meanings and concepts of it inside themselves. Also prominences of some national identity features rather than other features lead to formation of national identity and also play the important role in reinforcement and representation of national identity by repeating the meanings influenced by national identity.

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Iranian-Islamic architecture is a precious heritage of Shia culture which is the legacy of past generation, the valuable samples of which are well observed and recognizable in planning, design, and management system of historical cities of Iran. The relation between Iranian-Islamic architecture and theoretical basis, principles of Islamic jurisprudence, and verses of scripture and revelation shall be a valuable treasure in guiding and developing Iranian contemporary architecture and urban development. An overview of practical experiences and their theoretical foundation in the areas of architecture, urban development and urban management indicates that explaining the relation between theoretical principles and physical specifications is the prerequisite for realization and implementation of an architecture style and orientation; it is on the basis of such approach that the subject of the present research could be analyzed in the bed of Koran verses and their valid interpretations. The main research question is that what does identity mean in Islamic architecture? And where is the position of this definition in the formation of Islamic architecture? What are the requirements for realization of the rule of no injury loss in Islam in the bed of forming Islamic architecture? How Islamic architecture is formed in the bed of identifying elements and where is the position of these elements in Islamic architecture? The research method used in this study is based on a logical reasoning method. Upon drawing the theoretical framework of the research, the specialized and scientific resources are analyzed using comparative method, then the resulted opportunities and challenges are discussed. This research is required to be treated qualitatively, so it will be viewed based on free research paradigm using library sources and field study. The research findings indicate that the observance of 10 principles could be introduced as the realization of a rule of no injury loss in Islam in architecture and urban development system, especially in directing and planning urban development projects.

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This paper presents a framework for long term transmission expansion planning in competitive, electricity markets. Transmission lines and phase shifters are taken into account as expansion options. Maximization of the network users' benefits, with satisfying security constraints are considered as the criterion for transmission expansion planning. The elements of the objective function are the benefits of each network. The proposed model is as a non-linear mixed-integer programming (NLMIP) optimization problem. A GA (Genetic Algorithm) based method and quadratic programming (QP) approach is used to solve the problem. The discrete decision-making variables of the expansion plan are optimized by genetic algorithm, while QP optimizes the continuous variables.

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Arbitrage is a known economic term, implying simultaneous transaction on commodities. For instance, a Generation Company (GenCo) may involve itself in selling fuel, emission allowance and etc., instead of generating either active or reactive power. Moreover, arbitrage between active and reactive powers can, in turn, be considered. In this paper, arbitrage between active and reactive power is considered from Independent System Operator (ISO) viewpoint. A pool model is employed. ISO runs an optimization problem, by which, it could determine and predict GenCos behaviours; in terms of participating in active and reactive power markets for the next twelve months. A normal distribution function is used for price forecasting. Two 3-bus and 14-bus test systems are used to demonstrate the capabilities of the proposed algorithm.

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Network expansion studies normally offer new power lines, new substations or expansion of existing substations. They are generally proposed based on technical requirements, but financial restrictions are not considered. Because of financial restrictions, ranking of network expansion plans is required. In this paper an algorithm for such ranking, based on technical and financial view points and proposes suitable parameters. This algorithm may be used to compliment static or dynamic expansion planning studies of electric power networks.

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Working memory as a cognitive system is considered as one of the sources of individual differences in second language learning by many researchers. In order to examine the relationship between the capacity of two components of working memory (as one of the sources of individual differences in learning) and learning English vocabulary and grammar (as basic components in learning a second language), and also to explore the effect of instructional method as an effective variable along with working memory capacity, a convenience sampling method research was conducted. Subjects of this study were 74 female language learners selected from children between 9-12years old. These learners were at the beginner level in terms of English language proficiency. In order to determine the phonological loop capacity, non-word repetition test and digit recall test were used and, counting recall test and backward digit recall test were employed to determine central executive capacity. Based on the scores of these tests, language learners were divided into two homogeneous groups. The first group received inductive instruction and the second group underwent deductive instruction. Linear regression and two sample independent t-test were used for data analysis. The results indicated that both the phonological loop capacity and the central executive capacity had a significant effect on English vocabulary and grammar learning. Moreover, deductive teaching method significantly leads to better results in terms of grammar learning compared to the inductive teaching method.
 

1.  Introduction

Second language teachers observe significant differences between language learners regarding learning speed and final achievement in classrooms. Many factors can lead to such individual differences in learning a second language. Working memory as one of these sources of individual differences has been the focus of attention by many researchers over the past three decades. Learning a second language depends on a set of cognitive processes and systems, and working memory is one of these cognitive systems. Accordingly, this study attempts to find the effect of working memory on second language learning in children and under various instructional methods as a subject that has remained almost untouched, especially in Iran. Baddeley’s model of working memory was adopted as the theoretical framework of this study.
Research questions:
Q1- Do the capacity of the phonological loop and the capacity of central executive as two components of working memory have a significant effect on learning English vocabulary and grammar in 9-12-year-old children?
Q2- Does the deductive instructional method compared to the inductive method have any more significant effect on learning English vocabulary and grammar in 9-12-year-old children with almost the same level of working memory capacity?

2. Literature review
Working memory is a term that has grown out of memory studies and refers to the active processing system that manipulates information, explains our ability to remember information, and often occurs despite distracting information that we have to ignore (Alloway & Alloway, 2010). According to Baddeley (2015) to explore the role of working memory in learning a second language, which is a relatively new research field, it is necessary to conduct more extensive researches in different languages, different age groups, and different environmental and educational conditions. The greater the number of studies, the more accurate the results and findings will be. A number of studies have confirmed that the phonological loop capacity plays an important role in vocabulary learning. Martin and Ellis (2012), Kormos and Sáfár (2008), French (2006) and O'Brien et al. (2006) are examples of these researches. Moreover some studies indicate that working memory plays an important role in the production and processing of second language such as Trude &Tokowicz (2011), Gass and Lee (2011), Finardi and Weissheimer (2009), Leeser (2007), French (2006) and Sunderman and Kroll (2006).

3. Methodology
This research is a quasi-experimental classroom research. Convenience sampling was used in recruiting the subjects of this study. The study was carried out at Lesan English language institute in Gorgan, Iran. The age of the participants ranged from 9  to 12. The participants consisted of 74  language learners who were beginners in terms of English language proficiency level and had almost no knowledge of English writing, speech, vocabulary, and grammar. Initially, the students took 4  subtests of "working Memory Test Battery for Children". To determine the phonological loop capacity, two tests of non-word repetition and digit recall were used, and to determine the central executive capacity, two tests of counting recall and backward digit recall were taken. Learners were divided into two homogeneous groups according to their working memory test results. 36 of these language learners were taught inductively (-rule-explanation, +production-practice, self/pair-correction) and 38  were taught deductively (+rule-explanation, +production-practice, teacher-correction). Both groups completed 21 instructional sessions. During the instructional sessions, both groups took four classroom written tests and four oral tests, and the average scores of the subjects in vocabulary and grammar were considered as a criterion for their learning. The relationship between the phonological loop and the central executive capacity and the scores of English grammar and vocabulary as a learning criterion were examined to determine whether there is a significant correlation between them or not. First, the reliability of collected data and data distribution normality were checked and confirmed. Then the effect of the phonological loop and the central executive capacity was first examined separately and then in combination with the learning of English vocabulary and grammar.

4. Results
The results revealed that both independent variables, namely the phonological loop and the central executive capacity (both separately and in combination) have a positive and significant effect on the dependent variables, English vocabulary, and grammar learning, in children. The capacity of the phonological loop has a greater impact on learning English vocabulary, and the central executive capacity has a greater impact on learning English grammar. Considering the second hypothesis, the results of this study indicated that there is no significant difference in learners’ performance regarding vocabulary learning in inductive and deductive instructional groups, but the learners of the deductive group performed significantly better in grammar learning than the inductive group. This may be due to the fact that attention is one of the functions of the central executive component and by reducing the pressure on working memory, or in other words, by reducing the need for simultaneous attention to form and meaning, better results can be achieved in learning grammar (specially for learners with poor working memory).
 

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Soft tissue abnormalities are often correlated with a change in the mechanical properties of the soft tissue. New developing non-invasive techniques with the ability of early detection of cancerous tissue with high accuracy is a challenging state of art. In this paper, a new method is proposed to investigate the liver tissue cancers. Hyperelastic behavior of a porcine liver tissue has been extracted from the in vitro stress-strain experimental tests of the tissue. Hyperelastic coefficients have been used as the input of the Abaqus FEM software and the palpation of a physician has been simulated. The soft tissue contains a tumor with specified mechanical and geometrical properties. Artificial tactile sensing capability in tumor detection and localization has been investigated thoroughly. In mass localization we have focused on deeply located tumor which is a challenging area in the medical diagnosis. Moreover, tumor type differentiation which is commonly achieved through pathological investigations is studied by changing the stiffness ratio of the tumor and the tissue. Results show that the new proposed method has a high ability in mass detection, localization and type differentiation.

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In this paper, the variations of the stress intensity factor and energy release rate have been investigated based on the displacement correlation and modified crack closure integral methods for external surface cracks in the autofrettaged functionally graded cylinder (FGC). Mechanical properties vary in the radial direction according to the desired function. Isotropic material behavior and bilinear elastoplastic stress-strain relationship are considered for the FGC. Autofrettage process induces the tensile residual stresses in the outer parts of the cylinder wall, which causing the undesirable effects on the external surface cracks. Many variables affect the distribution of tensile residual stresses. Effects of autofrettage ratio, volume fraction of material and cylinder thickness on the residual stress changes and addition, changes in the size and direction of surface cracks on the stress intensity factor and energy release rate are studied. The results show that the volume fraction has the greatest effects on both crack parameters. The axial cracks are critical in compared with circumferential and angled cracks. The principle of superposition can be used to determine the combinational effects of the residual stresses and applied loads on the behavior of cracks in the graded materials.

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Passive suspension system is used in most vehicles due to its low energy consumption and low cost in most vehicles. Therefore, today there is a challenge in order to enhance the suspension system. The aim of this study is to present a new method for Multi-Objective design of vehicle suspension based on the use of asymmetrical dampers (Nonlinear). Hence, It is shown that using these type of dampers with a choice of two type coefficient by which one of them is in compression and another one in expansion, will lead to a more optimal design compared to those in the literature. For this purpose, vehicle was modeled using full model with eleven degree of freedom under random road excitation. Then, since the tasks of suspension system are reduction of vertical acceleration exerted on passengers, reduction of pitch acceleration of sprung mass, improving road holding and reduction of the change of four wheel work space. Therefore, the problem is defined as a Multi-Objective problem with conflicting objectives which formulated and solved by NSGA-II algorithm. The obtained results indicated that using asymmetrical dampers leads to more efficient design compared to those methods with symmetrical dampers.

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Interference fitting widely used in the industry for connecting shafts and bushes. These type of joints are widely used as support of bearing machine parts. Rrepeated disassembling of shaft and bush interference fit, performed to repair and maintenance of machine parts, may cause serious damage to surface of joint parts depending on the roughness and surface quality of contact surface of joint parts. Bushes are usually expendable parts, but the shaft parts are long integrated and complex parts which supports other components of machine. So providing a way to repair the shaft surface can be considered crucial and leads to restoration of damaged shaft and reduced costs. In this study, we have investigated the effect of interference surface roughness on strength, friction coefficient of the contact surface and surface damage of interference fit joints during the disassembling procedure. Finite element and experimental analysis were performed to estimate friction coefficient in contact surface of joint parts. Also, magnified pictures of contact surfaces were applied, to evaluate the extent of damage in contact surface after disassembling of joints parts. Hard chromium plating was proposed to repair the shaft surface and the effect of hard chromium plating on strength of shaft and bush joints were measured experimentally. The results confirm successful use of hard chrome plating in repairing the shaft surface so that the strength of restored shaft joints were equal and in some instances even more than the initial joints.

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In this study, fatigue growth of external surface cracks on the autofrettaged cylinders under bending is investigated. Autofrettage is a process in which a thick-walled cylinder subjected to internal pressure with known amount, causing some portions on the inner zone of the cylinder deformed plastically. In this case, removing the pressure causes compressive residual stresses on the inner layers and tensile stresses on the outer wall. The goal is increasing the fatigue durability of the product by inducing residual compressive stresses into materials, but along with this, there are adverse tensile stresses which can decrease the life due to the outer defects. In this paper, the external cracks are in the forms of half-elliptical, semi-elliptical and semi-circle. Samples made by aluminum 2024 alloy. The cylinders were autofrettaged up to 40 and 60 percent. Cracks were located in circumferential direction and normal to cylinder axis. The numerical simulations were performed by finite element method. Experimental data and numerical results were compared. Results show that the number of load cycles to fracture, in the 60% autofrettaged cylinders are smaller than those for 40% and also smaller than the state without autofrettage. Distribution of stress intensity factor along the crack front is symmetric and crack grows in its initial plane which indicating the dominance of the first mode of failure during the crack growth. In all samples, after some steps of the growth, crack front transforms to the semi-elliptical shape until complete fracture.

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Scientific study of the major oil producers has always been one of the issues facing economic experts. The emergence of Organization of the petroleum Exporting Countries (OPEC) as a major player in the world oil market resulted in increasing researches on the behavior of OPEC and its members. Iran as the second largest oil producer in OPEC has achieved the special place in shaping the policies of this organization. This paper investigates the behavior of Iran in OPEC using monthly data from 1973:1 to 2015:12. Therefore, first model is estimated using Griffin linear model, and then it is estimated using a Markov Regime-switching method with two states: probability of fixed transition and probability of time-varying transition. The results of fixed transition probability method showed that the behavior of Iran is nonlinear; and collusion regime is the most common behavior for Iran, so that the chance of staying in competitive regime is 0.005 percent. In other words, over the period under study, Iranian behavior within organization has been frequently consistent with other members based on agreement and collusion and cartel-like rules. However, the findings of the time-varying transition probability method have not clearly determined factors affecting non-linear effects on the production behavior of Iran. 

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In this paper, effects of severe plastic deformation (SPD) on the fatigue crack growth, mechanical properties, texture, roughness and fracture toughness of Al-6063 were studied. The Al-6063 alloy was deformed by ECAP process. The average grain size refined to less than 100nm. The textural study conducted before and after ECAP process. The fatigue crack growth tests were performed for different load range at same load ratio. The yield and ultimate stresses increased about 230% and 79% after ECAP process, respectively. The elongation reduced from 16.6% to 7% after four passes of ECAP process. The fatigue crack growth rate increased after first pass of ECAP process. The Paris equation parameters changed before and after ECAP but there is no significant change for different load ranges. The fracture toughness decreased after first pass of ECAP process. The atomic force microscopy (AFM) were used for measuring roughness. The scanning electron microscope (SEM) pictures were made for fracture surface study. The ductile and fissured fracture with large dimples were seen before ECAP process. The fracture surface with refined dimples observed after ECAP process.

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Aerodynamic and optimal design of a blade of a horizontal axis wind turbine (HAWT) has been performed in order to extract maximum power output with considering the strength of the blade structure resulted from different loads and moments. A design procedure is developed based on the Blade Element Momentum (BEM) theory and suitable correction factors are implemented to include three-dimensionality effects on the turbine performance. The design process has been modified to achieve the maximum power by searching an optimal chord distribution along the blade. Based on the aerodynamic design, the blade loads have been extracted and the blade mechanical strength has been investigated by analyzing the thickness of the blade surface and the blade material. The developed numerical model can be considered as a suitable tool for aerodynamically and mechanically design of a turbine blade. The results for a 500 W turbine show that the turbine performance improves by 5% approximately, by modifying chord radial distribution. Yield stress analysis shows the effect of introduced chord distribution on the blade strength, in different blade thicknesses and different blade materials. In addition, optimum tip speed ratio for having favorable mechanical safety factor is derived. Three different airfoil are examined for this investigation and comparing their mechanical safety factor.

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In this study, the aqueous-alcoholic extract of thyme in yogurt was used with the aim of increasing the acceptability of consumption and improving its quality characteristics. Due to the better quality of local BkezIlam yogurt, inulin was added to its formulation in concentrations (0.05%, 0.075%, 0.1% and 0.125%). The produced samples were evaluated from the point of view of quality tests and compared with the control sample (yogurt without inulin and thyme). For this purpose, thyme extract in concentrations (2%, 4%, 6% and 8%) was added to the milk used in the preparation of yogurt.PH, acidity, hydration, water holding capacity, acetaldehyde, viscosity and total bacterial count were evaluated at 1, 6, 11 and 21 days after production.The results showed that in the experimental treatments, the results of pH, acidity, synersis, water holding capacity, acetaldehyde content, viscosity and total bacterial count during storage were significantly different from each other (P <0.05). However, there was no significant difference in organoleptic properties except odor and other properties as taste, consistency, color,  mouthfeel and general acceptance is not significant, which were evaluated by 10 trained judges (P <0.05). According to the results of this study, yogurt sample contains 0.125% inulin and 2% thyme has the lowest pH and increased acidity and water holding capacity for 16 days. Also, the sample containing 0.15 inulin obtained the lowest percentage of synersis and the highest number of bacteria after 21 days. In terms of viscosity and acetaldehyde, samples containing 0.125% inulin and 6% thyme had the highest values ​​at 7 and 16 days, respectively (P <0.05). The experimental results showed that during storage, with decreasing pH in the treatments, dry matter increases and fat decreases in the samples and the percentage of synersis decreases, which increases the viscosity.
 

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Macroeconomic policy makers and planners always use different tools to achieve economic goals. Credit control is one of these tools. The boom and recession of the financial sector of the economy are called the credit cycle, and of the real sector is called the business cycle. Credit as a complementary input for capital, intermediate goods, and primitive materials can be effective in improving business cycles. This study, by employing Structural Vector Auto Regressive (SVAR) model and using the annual data of Iran during 1973 to 2016, investigates the relationship between credit cycles and business cycles in Iranian economy. The results show that credit cycle has positive effect on business cycle, but business cycle has negative effect on credit cycle. Credit cycle fluctuations have the largest share in explaining the business cycle fluctuations, but business cycle ranks the fourth in explaining the credit cycle fluctuations following own variable, inflation rate and consumption shocks. The investigation of the co-movement between the credit cycle and the business cycle also show that the effect of the credit cycle on the business cycle is revealed from the second period and there is 24 years of co-movement between these cycles. Also, the persistence of the co-movement between these cycles in expansion - improvement phases has causes severe financial crises in the Iranian economy in the long run.

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The aim of this study is to investigate the effect of gelatin film containing Bifidobacterium bifidum and Lactobacillus rhamnosus bacteria on the survival of Staphylococcus aureus bacteria inoculated into rainbow trout meat as well as its physicochemical characteristics for 12 days during storage at refrigerator. Staphylococcus aureus was inoculated into fish samples with a concentration of 10⁶ log cfu/ml. Then the treatments (control group, rainbow trout samples packed with gelatin film, gelatin film containing each probiotic bacteria Bifidobacterium bifidum and Lactobacillus rhamnus with a concentration of 10⁹ log cfu/ml separately and gelatin film containing both probiotics) were prepared. Samples were packed in polythene bags and stored in refrigerator. Probiotic bacteria viability and Staphylococcus aureus bacteria count, pH, TVB-N, PV and TBARS were evaluated. According to the results, the survival of probiotic bacteria showed a decreasing trend during the study, and it was found that the survival of Bifidobacterium bifidum bacteria in gelatin film treatment and gelatin film treatment containing both probiotics on the last day respectively 6.81 log cfu/g and 5.37 log cfu/g and the viability of Lactobacillus rhamnosus bacteria was also reduced by 7.43 log cfu/g and 6.31 log cfu/g respectively in the mentioned treatments. Compared to the control group, probiotic films controlled the microbial growth of fish fillets well, while the gelatin film treatment containing both probiotics had the lowest rate. Chemical tests also had an increasing trend and their changes in all treated fish fillets were significantly lower than the untreated group (P<0.05). It was found that gelatin films containing probiotics, especially gelatin films containing Lactobacillus rhamnosus and Bifidobacterium bifidum, which had worked more successfully, had an effective antimicrobial effect against Staphylococcus aureus bacteria, and this coating can increase the shelf life of rainbow trout and this The category of products has a good effect.