In generalizing/partial typology, which has been the dominant approach in typology since the early 1960s, achieving language universals was the main concern. It is noteworthy that in this approach, achieving language generalizations is based on interlanguage comparison of specific structures such as causativization, passivization, and possession. Following the generalizing/partial typology approach within the systemic functional grammar, Matthiessen (2004) has sought to achieve language generalizations. In fact, having examined the ideational (logical and experiential), interpersonal, and textual systems of the ‘clause grammar’ of different and various languages, Matthiessen (2004) has achieved a series of typological generalizations/universals in the framework of systemic functional typology. It should be noted that these generalizationsrefer both to divergences (differences) and convergences (similarities) of language systems. In terms of his proposed typological generalizations, Matthiessen (2004) has argued that they can be applied in the description of any language and in the attempt to expand the typological explanations in the framework of systemic functional grammar as well. However, he has immediately stated that “It is not yet possible to propose a generalized map; but we have to move in that direction.” In line with Matthiessen’s claim mentioned above, the present paper has attempted to describe the THEME system of Persian language on the one hand and to compare it with the THEME system of English as the dominant foreign language in the area of education in Iran, on the other hand. This study has been conducted in the framework of systemic functional typology and specifically Matthiessen (2004) ’s typological generalizations in terms of the THEME system [1]. Matthiessen (2004) has identified the following areas as the principal parameters of typological variation in the THEME system of languages: (1) The treatment of unmarked and marked THEME, (2) The relationship between THEME and INFORMATION, (3) The relationship between THEME and MOOD, (4) The relationship between experiential (topical) THEME and interpersonal and textual THEME, and (5) The relationship between THEME and VOICE. In this research, in order to limit its scope, only three of the above domains have been selected as typological parametersfor describing the THEME system of Persian language and comparing it with the THEME system of English: (1) The treatment of unmarked and marked THEME (related to the subsystem of THEME MARKEDNESS), (2) The relationship between THEME and MOOD (related to the subsystem of THEME SELECTION), and (3) The relationship between experiential (topical) THEME and interpersonal and textual THEME (related to the subsystems of THEME TYPE, INTERPERSONAL THEME, and TEXTUAL THEME). This research is a ‘theoretical fundamental’ type in terms of aim and is a ‘pure descriptive’ type in terms of nature and method. Persian examples of this study have been obtained from various documents such as novel, research papers, and grammar books. However, some of the Persian examples have been made by the authors of this paper. English examples have been mainly taken from Halliday (2005) and Halliday and Matthiessen (2014). It is necessary to note that this research has described the THEME system only within the limits of the simple clause and has avoided dealing withclause complexes. Studying typological behaviors of the Persian THEME system in the framework of Matthiessen (2004) ’s typological generalizations and comparing those behaviors with the typological behaviors of the English THEME system showed that the two Persian and English languages (1) have similar thematic structures; Theme occurs in the initial position of the clause without any Theme marker, (2) treat both unmarked and marked Themes similarly; both marked and unmarked Themes occur in the initial position of the clause with the sequence ‘unmarked Theme + marked Theme’, (3) mark absolute Themes segmentally; Persian absolute Themes are marked by the postposition »ra «and English absolute Themes are marked by prepositions like» as to, as for, regarding«, (4) have both simple and multiple types of Themes; Theme can contain textual and interpersonal elements beside experiential one, and (5) treat the elements of a multiple Theme similarly; the elements making up a multiple Theme have all the same realizations, that is they are realized by the initial position of the clause. Another finding was that unlike English language whose THEME system is MOOD-bound, Persian language possesses a MOOD-free THEME system; in Persian language, unlike English, Subject (whetherpresent or dropped) is the unmarked Theme in all clause types except imperative clause. The results of this study indicated that the two languages of Persian and English behave similarly in terms of three typological parameters out of four ones related to the THEME system. The finding number (3) as mentioned above, showed that Matthiessen (2004) ’s convergence generalization in terms of THEME system, i. e. the possibility of marking Theme segmentally, is also true of Persian language. In the end, it is suggested that the typological behaviors of the THEME system of other languages spoken in Iran should be identified and introduced in the aforementioned framework.

In systemic functional typology, which studies the systems of languages rather than the whole languages, linguists strive towards empirical generalizations that in principle apply to all languages around the world. In line with the above-mentioned goal of systemic functional typology and having examined the ideational (logical and experiential), interpersonal, and textual systems of the ‘clause grammar’ of different and various languages, Matthiessen (2004) has achieved a series of typological generalizations/universals. In connection with his proposed typological generalizations, Matthiessen (2004) has argued that they can be applied in the description of any language and in the attempt to expand the typological explanations in the framework of systemic functional grammar as well. However, he has immediately stated that “It is not yet possible to propose a generalized map; but we have to move in that direction.”
In line with Matthiessen’s claim mentioned above, the present paper has attempted to describe the THEME system of Azeri Turkish on the one hand and compare it with the THEME system of Persian language on the other hand. This research has been conducted in terms of the following three typological parameters concerning the THEME system: (1) The treatment of unmarked and marked THEME (related to the subsystem of THEME MARKEDNESS), (2) The relationship between THEME and MOOD (related to the subsystem of THEME SELECTION), and (3) The relationship between experiential (topical) THEME and interpersonal and textual THEME (related to the subsystems of THEME TYPE, INTERPERSONAL THEME, and TEXTUAL THEME).
Studying typological behaviors of the Azeri Turkish THEME system in the framework of Matthiessen (2004)’s typological generalizations and comparing those behaviors with the typological behaviors of the Persian THEME system show that the two languages of Persian and Azeri Turkish (1) have an almost identical thematic structure, (2) treat both unmarked and marked Themes similarly, (3) have multiple types of Themes beside simple ones, (4) treat the elements of a multiple Theme similarly, and (5) have a MOOD-free THEME system. These findings show that both languages, which are genealogically different, have a similar THEME system and specifically the three subsystems of THEME MRKEDNESS, THEME SELECTION, and THEME TYPE. This result is consistent with ‘axial principle of congruence’. According to this principle, languages tend to be more congruent with one another in terms of paradigmatic axis/system than in terms of syntagmatic axis/structure.
In the end, it is suggested that the typological behaviors of the THEME system of other languages spoken in Iran be identified and introduced in the aforementioned framework.

The main question of the study is determining the status of thematic structure in declarative clauses in the writings of advanced non- Iranian Persian learners and determining the status of markedness. This study is corpus based and done by a descriptive and analytic method. The corpus includes 49 models of writing of advanced non-Iranian Persian learners of different nationalities who have studied at Persian Language Center of Imam Khomeini International University. To do this study, at first, the thematic structure was studied in declarative clauses in the writings of Persian learners, then the kinds of themes as the point of textual, interpersonal and experiential were determined. After that, unmarked and marked themes were determined. Finally, the obtained data was presented using descriptive statistics. The findings indicated that the frequency of using experiential and multiple themes in declarative clauses was equal (each 43%). Additionally, the frequency of clause themes was 14%. Among the multiple themes, textual- experiential theme had the most frequency (88/43%). The findings also confirmed the hypothesis that the most of the themes (81%) was unmarked and the frequency of using unmarked themes in declarative clauses in the writings of advanced non-Iranian Persian learners was different in various nationalities.

In the present article, theme-theme structure in clause-complexes of specialized texts (such as biochemistry, physics and anatomy) is studied based on SFG. At first, clause-complexes types in theme-theme structure of scientific texts are classified, and by describing and analyzing different types of clause-complexes (dependent/ dominant) it is revealed that these clauses are used more than simple ones within the whole corpus. Then, theme-theme structure is analyzed, and the result illustrates that clause analysis is possible at one, two or three layers at the same time, depending on the clause type. Therefore, one can find layers of themes in such clauses and introduce the notion of layer theme. Studying simple/complex themes revealed that in the scientific genre, complex themes are used more than textual ones. This is because the sequences of textual themes in the scientific texts are something usual. Complex clauses, complex themes and multiple layers of clause analysis indicate speech adjuncts in scientific texts, and consideration of such structural elements is effective in discourse organizing, text development and perception process. This is useful for text evaluation and can be considered as a criterion for transfer of information to the addressee, as it is seen in physics, biochemistry and anatomy texts respectively.

One of the important components in Halliday's systematic role-oriented linguistics is the category of subject-predicate, by means of which the process of initialization and construction of old and new information can be investigated in any text, including Manteq-al- Tayr. Therefore, with the descriptive-analytical method, we are trying to investigate the problem of simple and compound primers according to Michael Halliday's approach in Manteq-al-Tayr. The purpose of the research is to investigate the frequency of the most types of initiators, scrambling, and to explain the verbal purposes hidden in the depth of the textual structure of Manteq-al-Tayr. The results of the research show that the percentage of multiple themes is more than simple themes, which indicates the affinity of the text with the speech, and also, Attar has used all the capacities to facilitate readers' understanding. In the simple themes, the poet has used the initial construction of the verb, more than other initial constructions of object, complement, adjective, interrogative and adverb, which has made the construction of information clauses stand out and marked. Among multiple themes, textual primers have a higher frequency than interpersonal primers. Textual primers have played a significant role in the textual coherence of Manteq-al- Tayr.

In Haliday’s Systemic Functional Grammar (SFG)، there are three metafunctions that actually are three semantic layers of clauses of a language; being aware of them are important in transferring meaning in the process of translation. Regarding the crucial importance of transferring meaning faithfully in translation، particularly meanings beyond the propositional meaning of an utterance، here، we study the semantic changes of the structures termed “predicated themes” in SFG. Data investigation revealed that in ideational، interpersonal، textual and also information structure of many predicated themes translated into Persian، we see changes that sometimes have ended in missing of some important parts of meaning. In case of being aware of the different semantic layers of structures like predicated themes، many of these kinds of semantic changes are avoidable; consequently، it is possible to transfer meaning of the source language more faithfully to the target language. Therefore، the main goal of this article is to investigate the semantic changes of predicated themes in the process of translation. The next goal of the research is providing some ways for minimizing these kinds of changes.

Cylindrical thin-walled tubes due to construction and easy installation, high energy absorption capacity are used in the automotive industry as an impact energy absorber. However, the main weakness of cylindrical tubes is in the high initial peak load. Therefore, in this paper, to overcome this weakness, a buckling initiator is used at the top of the tube. This buckling initiator is a steel rod that is installed by stretching strips at the edge of tubes. In this study, the parameters related to the initiator, including different number of pulling strips N, pre-hit height h and inclined angle of the pulling strips θ are studied. For this purpose, quasi-static simulation was conducted to determine the maximum crushing load, specific energy absorption and crush force efficiency using the software Ls-Dyna. To verify the numerical simulation, the results were compared with experimental testing. The results show that the crashworthiness characteristics and performance of the cylindrical tubes significantly improved with buckling initiator.

Cylindrical thin-walled tubes due to construction and easy installation, high energy absorption capacity are used in the automotive industry as an impact energy absorber. However, the main weakness of cylindrical tubes is in the high initial peak load. Therefore, in this paper, to overcome this weakness, a buckling initiator is used at the top of the tube. This buckling initiator is a steel rod that is installed by stretching strips at the edge of tubes. In this study, the parameters related to the initiator, including different number of pulling strips N, pre-hit height h and inclined angle of the pulling strips θ are studied. For this purpose, quasi-static simulation was conducted to determine the maximum crushing load, specific energy absorption and crush force efficiency using the software Ls-Dyna. To verify the numerical simulation, the results were compared with experimental testing. The results show that the crashworthiness characteristics and performance of the cylindrical tubes significantly improved with buckling initiator.

Restoration, reconstruction, renovation and rehabilitation of the monuments and architectural of the past is a notable aspect of architectural course in the Timurid period. The pioneer of this course was Timur (Tamerlane) himself. He spent much wealth for the
construction, and rebuilt some of the remaining buildings. His son and successor, Shahrukh, overtook his father in the architectural patronage and reconstruction. In the reign of Shahrukh, the princes and courtiers got relatively authority for restoration. After Shahrukh, this process was continued by Timurid kings like Mirza Abu’l-Qasim Babur and
Sultan Abu-Sa’id. Sultan Husayn Bayqara and his vizier, Ali-Shir Nava’i rebuilt some of the previous buildings. Many of the officers, as well as rich people out of the court, increased buildings through various constructions. In comparison with the vast architectural
activities in Timurid period, what is remained is little. However, the Timurid historians’ reports can compensate the shortage of information relatively. It seems that this part of Timurid architecture has been neglected by scholars.