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This study aims to investigate and analyze the realization of grounding in the form of foregrounding and back grounding in Persian-children’s narratives according to linguistic devices of aspect (perfective/imperfective) and voice of verb (active/passive) and also the effect of age on using these devices.
To investigate how foregrounding and back grounding are accomplished in Persian-speaking children’s narratives by linguistic devices of aspect (perfective/imperfective) and voice of verb (active/passive) two Hickmann’s (2004) pictorial stories were used. Three groups of school monolingual Persian-speaking children of age 7, 9, 11 and a control group of adults, at age 30 (each group consisting of 10 female subjects) took part in this study. The subjects were tested individually. They were asked to narrate two pictorial stories for one of the researchers. All the narratives (80 narratives, from two pictorial stories) were recorded by a voice recorder. Then, they were transcribed, described and analyzed by SPSS software.
Results showed that the use of perfective and imperfective aspects had a meaningful relationship in the three groups of children, that is, the use of perfect aspect in foreground decreased while that of imperfect aspect increased with an increase in the age. On the contrary, in adult group, the use of perfect aspect in foreground increased but that of imperfect aspect decreased. The same relationship was observed in background. Moreover, the use of active voice of verb was more dominant than that of passive voice of verb in the narratives. No meaningful relationship was observed between the use of passive voice of verb in foreground and background on one hand, and the participants’ age, on the other hand. Based on the results of Chi-square test, there was a significant relationship between perfective and imperfective aspects in foreground and also in background and the age of the narrators (p < 0.05). However, there was no significant relationship between the use of passive voice of verb in foreground and background and the age of the narrators (p < 0.05). Thus, the first two null hypotheses of the study were rejected, and the third one was accepted.

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Genus Lentinula comprises some of the most important edible and medicinal fungal species of the world. To compare growth rate of the strains of this genus, samples were collected from different regions of the world including Iran during 2017-2018. Investigation of the growth of 40 strains on two substrates containing malt and wheat straw extracts showed their relatively excellent performance on both media. Based on preliminary growth characteristics of the strains, 20 strains were selected to study their growth rate on natural substrate containing defined proportion of straw (40%) + sawdust (40%) + wheat bran (20%). Three strains including VM230 (UK strain), VM267 (Belgium strain) and VM353 (Japanese strain) showed high growth rate (65.25, 63.75 and 64.50 mm d^-1, respectively), and were identified as Lentinula edodes by ITS4 and ITS5 sequencing. Growth rate of the best strain (VM230) was evaluated on different substrates containing different proportions of straw, sawdust and wheat bran. The highest growth rate (58.75 mm d^-1) for VM230 was recorded on wheat straw (80%) + wheat bran (20%). These three strains are promising for commercial production of Shiitake.
 

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The aim of this study is to investigate the effect of the addressee’s power and gender on the choice of the type and number of encouragement strategies employed by Persian male and female university students based on Brown and Levinson’s (1987) theory.  A number of 60 M.A. students (30 males and 30 females) from the University of Sistan and Baluchestan participated in this study. Discourse completion test and role play technique were utilized as two data gathering instruments. The data were analyzed using the Chi-square and Independent-T test (p<.05). The results indicated there was a significant relationship between the addressee’s power and the type as well as the number of encouragement strategies employed by male and female university students. The most frequent strategy type was the “negative politeness” giving deference for the addressee with higher power (the professor). As to the number of strategies, the most and less frequent ones were the combination of two and nine strategies, respectively. The addressee’s gender had an effect on the type of the strategies used by male students in three situations; while it didn’t have any effect on the number of strategies used by male students and also on the type and number of strategies employed by female students. The most frequent strategy type used by female students was the “positive politeness” and the combination of three strategies for male and female addressees; by male students: “positive politeness” for male addressees and “negative politeness” and the combination of two strategies for female addressees.


1. Introduction
Interpersonal interactions and how they are formed play a significant role in human social life. One way to interact is through using different speech acts. Many factors can involve in making use of politeness principle in interacting and communicating. In life and social interactions, human beings use various speech acts such as request, agreement, disagreement, swearing, giving advice and encouragement in order to express their meaning. One of the most important and effective theories in pragmatics field is Austin’s speech act theory. He believes that every sentence may have a performative feature and also it has an action within it; therefore, every sentence should be considered within its context (Austin, 1962). Employing the speech acts depends on various factors such as language characteristics and socio-cultural frameworks. Among these factors, politeness is one of the crucial factors in interpersonal communications in different societies and cultures. Politeness can be represented in various aspects of behavior based on the factors such as the addressee’s social status, power, and gender in using speech acts. One of the most widely used speech acts among their various range in interpersonal interactions is the encouragement speech act. If this speech act is appropriately used in the right context, it will have important effects on relations between individuals as well as on saving face based on power and gender of the addressee. Thus based on what is mentioned and according to the importance and impact of the encouragement speech act in every person’s social life, the type and number of encouragement strategies and the effect of the addressee’s power and gender on the use of this speech act by Persian language male and female university students can be investigated and analyzed based on Brown and Levinson’s (1987) politeness theory. The research data were gathered via two data collection tools including discourse completion test (DCT) and role-play technique. The hypotheses of the present study are as follows:
1. Due to the addressee’s power, there is a significant difference in the useage of the type of encouragement speech act strategies among Persian-speaking male and female university students.
2. Due to the addressee’s power, there is a significant difference in the usage of the number of encouragement speech act strategies among Persian-speaking male and female university students
3. Due to the addressee’s gender, there is a significant difference in the usage of the type of encouragement speech act strategies among Persian-speaking male and female university students.
4. Due to the addressee’s gender, there is a significant difference in the usage of the number of encouragement speech act strategies among Persian-speaking male and female university students.

2. Literature Review
By considering linguistic, cultural, and social characteristics of language, different speech acts have been examined by many researchers. Rahimpour and Yaghubi Noutash (1999) investigated the impact of gender and subject on speech act in English language learners. Amou Ali Akbari Najafabadi (2007) has conducted a research to examine the Social-interpersonal power and politeness strategies in Persian. Pishgadam and Rasouli (2011) examined the persuasion speech act strategies among Iranian language learners by considering speaker’s gender. Zeynali Dastuyee (2012) studied the effect of addressee’s power and gender on the type and number of apology and refusal strategies employed by Sarawani university students. Shafaghi (2013) investigated the promise speech act and the use of promise in political discourse. Pishghadam and Attaran (2015) studied the speech act of argumentation in English and Persian advertisements. Azarparand (2019) has investigated changes in addressing strategies based on Brown and Levinson's Politeness theory. This case study research has been conducted in Tehran University among Iranian lecturers and students.

3. Methodology
In the present study, the effect of the gender and power of addressee variables on the choice of politeness strategies in encouragement speech act in Persian language is investigated. This study is a descriptive-analytical research. A number of 60 M.A. students (30 males and 30 females) from the University of Sistan and Baluchestan participated in this study. Their age was ranged from 23 to 34 years old. They had an average age of 25 years. All subjects were randomly selected, were monolingual, and Persian-speaking postgraduate students who were studying in different fields of study. Discourse completion test (DCT) and role play technique were utilized as two data gathering devices. The questionnaire which was used in the study was a researcher-made one. The data were analyzed using Chi-square test, Analysis of variance (ANOVA), and Independent T-test.

4. Results
The present study examined the encouragement speech act based on two determining variables including the power and the gender of the addressee in different contexts. The findings of the study show that the addressee’s power can be an important and effective factor in the selection of the type and number of the encouragement strategies. The most frequent strategy type is the “negative politeness” strategy. In addition, the addressee’s power has an effect on the number of the encouragement strategies employed by male and female university students. As the power of the addressee increases, the use of more complex strategies becomes more and simple strategies are utilized in dealing with the addressee with low power. As to the number of the strategies, the most frequent and less frequent ones are the combination of two and nine strategies respectively. The results also indicate that the gender of the addressee affects the type of the encouragement strategies used by male university students while, it doesn’t affect the number of strategies used by male students. It also doesn’t have any effect on the type and number of the strategies used by female university students. Also, data analysis reveals that there is no significant relationship between the addressee’s gender and the number of the encouragement strategies. In other words, the addressee’s gender has no effect on the number of the encouragement strategies used by male and female university students

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The aim of this study was to determine the kinetics, effective moisture diffusivity, activation energy, specific energy consumption, and also predict the moisture content of white mulberry during the drying process with microwave-hot air dryer using mathematical models, Artificial Neural Networks (ANN) and Neuro-Fuzzy Inference System (ANFIS). Drying process was accomplished in three temperature levels (40, 55, and 70°C), three inlet air velocity levels (0.5, 1 and 1.5 m/s) and three microwave power levels (270, 450 and 630 W). To estimate the moisture ratio of white mulberry, 10 mathematical models, ANN and ANFIS were used to fit the experimental data of thin-layer drying. The results showed, the maximum and minimum effective moisture diffusivity during drying was calculated 3.56×10-9 and 3.86×10-10 m2/s, respectively. Also, the minimum and maximum effective moisture diffusivity during drying was achieved 48.54 and 1380.88 Mj/kg, respectively. Among the mathematical models under study, the Page model was the best model for describing the behavior of the thin layer of white mulberry drying. The mean square error (MSE) values for the mathematical models, ANN, and ANFIS were 0.00059, 0.0052 and 0.0044, respectively. Therefore, the ANFIS model with the highest Correlation Coefficient (R2=0.99995), the least percentage of mean relative error (ε=1.84) and mean square error (MSE=0.0044) were used to evaluate the moisture ratio in comparison with other methods implemented in this research Selected as the best model

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In this research, errors and accuracy of a 5-axis machine tools are investigated using a balbar device. The focus is on the measurement of positional errors and rotational errors related to rotational axes. Therefore, first, using homogeneous transformation matrices and based on the kinematic chain of machine axes, a mathematical error modeling is done for each axis in order to get an overview of the impact of errors on machine operation. In the following, a method to measure these errors is proposed, and to validate this proposed method, its results are compared with a valid method. Homogeneous transformation matrices (HTMs) are used to create a machine tool model and generate bearing error diagrams due to machine tool geometric errors based on the given experimental design. Simulated payload trajectory patterns can be used to evaluate unique fault effects for detected faults and to diagnose machine tool conditions.

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Gears are a very important part of mechanical equipment in industry. Due to the fact that in mechanical processes, the teeth are subjected to long-term load, the surface of their teeth is usually rusty, worn out and even broken. Timely fault detection cannot only increase the life cycle of the gears, however it can even prevent property losses and losses due to breakdowns. Therefore, it is necessary to monitor and diagnose the health of the gears to ensure the normal operation of the invaluable machines in industry. In this research, fault detection in polymer gears using audio signal is considered as a non-contact inspection method. Sound signals were recorded from 50 pairs of gears in normal condition, worn teeth and broken teeth at two speeds of 66 and 99 rpm. In the following, using wavelet packet transformation (WPT), the sound signal is analyzed in the time-frequency domain and 12 statistical features are extracted from the 16 coefficients of the fourth level of WPT. In order to study the performance of the fault detection algorithm, four classifications of linear discriminant analysis, K-nearest neighbor, decision tree and support vector machine have been used. The values of accuracy, true positive rate, true negative rate, positive predictive value, negative predictive value, geometric-mean, F1 score, and Matthews correlation coefficient have shown that by using WPT, a significant distinction can be found between normal and faulty gears. Therefore, the proposed method is a suitable approach for timely error detection of polymer gears used in mechanical equipment.