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This study aims to analyze the attitude and use of ritual poems in different rituals. The instrument to collect the related data was a research-made questionnaire. It consisted of 26 items on the attitude and use of Sistani poems in different rituals. To test the reliability of the questionnaire, the Cronbach alpha was administered. the population was all individuals above 20 in Zabol city and its surrounding villages. The research sample, though, was 384 individuals based on Morgan's sampling table. This was done through random sampling. To test the hypothesis, the Chi-square was employed in SPSS software. The findings indicate that the participants have a positive attitude to ritual poems, but do not use them in their rituals as before.

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This study aimed to critically analyze the promotional texts in nature schools within Ecolinguistics approach. Data collected through telegram channels of nature schools over the past three years.These texts are often taken from Vahhabzadeh(2013 and 2016). Finally,45 discourse texts were selected, comprising a total of 274 clauses. Each clause was analyzed based on Hallidays systemic functional grammar from the perspective of experiential, interpersonal, and textual metafunctions, and ultimately they were ecolinguistically examined. The relationship between human and the environment and understanding the views and attitudes of these schools are among the issues were examined. The results showed that the content of 168 clauses, i.e. 61 percent of clauses, encourages humans to conserve the environment and make proper use of nature and  In 149 cases, approximately 55%, there is a human-nature or nature-friendly relationship. As a result, these schools play a key role in changing human attitudes toward the environment, leading children to conserve nature.
 

Critical Discourse Analysis of Educational Texts in Nature Schools: An Ecolinguistics Perspective Received: 13 December 2019 Received in revised form: 8 March 2020     Accepted: 7 April 2020   Sedighesadat Meghdari1* & Masoome Yousefi2 Abstract This study aimed to critically analyze the promotional texts in nature schools within Ecolinguistics approach. Data collected through telegram channels of nature schools over the past three years.These texts are often taken from Vahhabzadeh(2013 and 2016). Finally,45 discourse texts were selected, comprising a total of 274 clauses. Each clause was analyzed based on Hallidays systemic functional grammar from the perspective of experiential, interpersonal, and textual metafunctions, and ultimately they were ecolinguistically examined. The relationship between human and the environment and understanding the views and attitudes of these schools are among the issues were examined. The results showed that the content of 168 clauses, i.e. 61 percent of clauses, encourages humans to conserve the environment and make proper use of nature and  In 149 cases, approximately 55%, there is a human-nature or nature-friendly relationship. As a result, these schools play a key role in changing human attitudes toward the environment, leading children to conserve nature. Keywords: Ecolinguistics,Critical discourse analysis, Nature schools, Systemic Functional grammar.

1. Introduction
 Environmental linguistics, by nature , is the critique of language forms contributing to environmental degradation and helping the exploration new forms of language that encourage people to protect the environment. This research aims to do an ecolinguistically critical discourse analysis on nature schools texts.
Research Question(s)
What is the relationship between man and nature in the propaganda texts of nature schools?

2. Literature Review
"Environmental Linguistics" is a book translated by Aghagolzadeh (2016) is the most comprehensive and complet book in Persian. Shahnaseri (2009) has ecolinguistically analyzed the shortcomings of science at both lexical and grammatical levels. Maleki et al. (2016) introduced the typology of environmental discourses in of Islamic National Parlement negotiations. Mirsaeedi (2016) showed the poems contain litral devices such as metaphor, prsonafication and so on can be considered as a model for turning Persian into a green language. Ghiasian and Shirini (2016) research is a decoding of humanism institutionalized in Persian language and culture. (see also Miboudi et al. (2014), Qatreh et al. (2015),  Rakaei and Naeemi (2016), Khairabadi (2015) and Mushtaqimehr and Faizi (1397) for similar disscussion).

3. Methodology
This research is done through Halliday's systematic- functional theory (2004), namely. experiential, interpersonal, and textual metafunctions from the perspective of ecolinguistically critical discourse analysis.
4. Results
Results obtained from experimental analysis of 274 clauses as the research data indicated relational process has the highest frequency with 107 items. This verifies the claim that relationships have a special place in the texts of nature schools. Results obtained from interpersonal analysis showes non-mentioned subject has the highest frequency, indicating the authors of nature school texts pay less attention to interaction and only play an informative role. The next case is positive polarity, which has the highest frequency with 201 cases, and shows that the author has presented his views with determination in most of his texts. The statment with a frequency of 228 is in the first place and shows the authors interst to give too informations to the readers. Application of grammatical aspects suggestes that the affirmative aspect with a frequency of 215 has the highest frequency. It indicates the author has a high degree of certainty. Results obtained from textual analysis shows the experimental initiator has the highest frequency indicating the authors seek to attract the audience's attention. The promotional perspective of nature schools analysis showed approximately 61% encourages human beings to preserve the environment.Finally, the relationship between man and nature in the studied texts indicates that in approximately 55%, there is a friendly relationship between human and nature.


 

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In this paper the goal is to identify the parameters of the Lorenz chaotic system, based on synchronization of identical systems using fractional calculus. The method which is used for synchronization is come from Lyapunov stability theorem and then by using fractional dynamics, control laws are improved. To this end, a Lyapunov function is presented and based on the Lyapunov stability theory and asymptotic stability criteria, some adaptation laws to estimate unknown parameters of the system are proposed. The introduced method is applied to the Lorenz chaotic system and since the goal is identification, all the parameters of the system are taken unknown. Using invariant set theory, it is proved that the parameter estimation errors converge to zero. Then the results of numerical simulations are shown and discussed and it is observed that fractional calculus has an essential effect on reducing fluctuations and settling time of the parameters convergence. At the end, the stability of the system by using fractional adaptation law is discussed. It is shown that the asymptotic stability of the synchronization error dynamics is proved using the fractional adaptation law, and this is confirmed through simulation.

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Kinematic trajectory optimization of the dual-arm cam-lock parallel robot in the different lock configuration has been done in this paper. A different path has been considered for each of lock configuration. The optimal trajectory of each joint has been calculated by minimizing an objective function in whole trajectory. According to the number of redundancy in the different configurations, an initial guess of the variables have been considered. Then the initial guesses have been modified and optimum results have been obtained by using Pontryagin’s minimum principles and determining the governing initial condition on the system. According to the optimal joint variable, optimal trajectory has been obtained for each of the joints. In all of the configurations, optimal performance index has been achieved. Also the direct kinematic equations have been considered as the constraints of the system.

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In this article, stability analysis for Stochastic Piecewise Affine Systems which are a subclass of stochastic hybrid systems is investigated. Here, additive noise signals are considered that does not vanish at equilibrium points. These noises will prohibit the exponential stochastic stability discussed widely in literature. Also, the jumps between the subsystems in this class of stochastic hybrid systems are state-dependent which make stability analysis more complex. The presented theorem considering both additive noise and state-dependent jumps, gives upper bounds for the second stochastic moment or variance of Stochastic Piecewise Nonlinear Systems trajectories and guarantees that stable systems have a steady state probability density function. Then, linear case of such systems is studied where the stability criterion is obtained in terms of Linear Matrix Inequality (LMI) and an upper bound on state covariance is obtained for them. Next, to validate the proposed theorem, solving the Fokker Plank equations which describes the evolution of probability density function, is addressed. A solution for the problem of boundary conditions that arises from jumps in this class of systems is given and then with finite volume method the corresponding partial differential equations are solved for a case study to check the results of the presented theorem numerically.

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In this paper design, fabrication and control of a robotic fish with flexible tail was presented. At first, the short introduction of the robotic fish and their common control algorithms were reviewed. At the next step, the proposed mechanism of the robotic fish and its design procedure of the mechanical and electrical subsystems were explained. Mimic of the proposed robot was inspired from the Rainbow trout. The mechanical structure of the robotic fish consists of a body and a flexible tail. Oscillatory actuation of the tail was carried out utilizing a servomotor which was manipulated by pulse width modulation signal. The electrical subsystem of the proposed robot containing the electrical boards, electronic circuits, and a microcontroller are installed on the Aluminum platform which is locating in a sealed case. The flexible tail is attached to the end-side of the sealed case, and the actuating force is transferred to the tail utilizing pulley and cable mechanism. Since the dynamics of the system under investigation is nonlinear, a fuzzy logic controller is proposed to control the movement of the robot for goal seeking purpose. The closed loop simulation of the system was carried using MATLAB software. In addition, experimental investigation of the robotic fish was performed in the laboratory.