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Estimating the size of shadow economy is of special importance in setting macroeconomic variables and fiscal policies. In recent years, the fuzzy inference sets have been used for measuring shadow economy. In this paper, we present eight new fuzzy indicators for modeling and estimating the size of shadow economy. Thus, according to Lucas definition, we divide the shadow economy into four sectors and define two indicators for each sector. After three fuzzy inference phases, we measure the size of shadow economy. Our results indicate that the effect of production household on Iran’s shadow economy size is decreasing; and irregular, informal and illegal sectors impact size of shadow economy. In addition, the size of Iran’s shadow economy is estimated around 13 percent of GDP, on average, over 1970- 2007.  

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Today, the structure of the Arabic press language has suffered from damages that need to be addressed. These problems are mainly due to insufficient attention to grammar rules. There are also some pronunciation and expression problems that cause non-standard language patterns to penetrate the press language. Therefore, it is necessary to recognize these patterns and replace them with standard language patterns. Since Arabic has different types of languages ​​and dialects, it is the standard language that can maintain coherence and unity between them. Promoting and reinforcing standard language patterns is the main job of writers, editors, journalists, and anyone who uses language professionally. Obviously, what is said by these people is usually considered as a standard language and spreads to other educational centers and the media. Currently, the language of the Arabic press suffers from the shortcomings and damages that have affected the body of the language. The media should try to enrich the Arabic language capacities and take advantage of all its possibilities and provide the grounds for the growth and development of the press language, along with extensive social, cultural and political developments, a flood of foreign aggressive words, the increasing speed of innovations and the arrival of new achievements.

1. Introduction
Language is the most important tool to transfer human experience and knowledge. Each society has to have a standard language so that it can be used as the most important communicative factor among people. When non-standard language patterns are propagated, they are accepted as standard patterns across time. As a result, language becomes imperfect and defective from various aspects. The effect of thinking methods and political and social attitudes on language structure is the issue that cannot be ignored. In Arab countries, newspapers which have Islamic attitudes have a special language compared with those that have ethnocentrism attitudes and the newspapers that have just commercial feature. In the text of these newspapers, Quranic words and expressions related to the scope of philosophy, logic and Islamic language are mostly used and a kind of preaching tone can be observed.
The term pathology may not be correct about other languages which traverse natural path of language but it is true about Arabic which is a rhetorical language and has been shaped since 1400 years ago and remained since then.
The main hypothesis of this study is that the most important role of media like press is educational role. Given the pervasive role of media, what is learnt via official references is not at all comparable with degree of effectiveness from the media. But today it is observed that most newspapers work based on trial and error. Permanent engagement in translation, edition or generating public scientific texts without continuous training quickly reduces the awareness of newspapers authors to the level of public scientific topics.

2. Literature Review
In this scope, any resource which criticized and pathologized the standard and press language accurately has not already been published but some resources in which the press language has been referred to some extent are as below: 1) language in the press written by Abdul Rahman Faramarzi: in this book, the process of journalism and press has been explored. 2) Moderm journalism written by Na'im Badiee and Hossein Ghandi: in this book the authors have attempted to make the readers familiar with principles of modern journalism. 3) MA thesis entitled language in the press written by Zhila Ebrahimi: in this thesis, it has been tried to explore the journalistic text which is one of the evidences of standard language from the linguistics viewpoint. 4) The paper entitled the issue of language in mass communication tools, a conversation with Dr. Sahabi: the author in this paper emphasizes that the mass communication tools are the main element of today culture.  5) Mostalahat-e Motadavel fi Al-Sahafi Al-Arabiah written by Mohammad Reza Azizpour: the author has inserted the common expressions of Arabic newspapers along with the selected samples of news. 6) Laghv Al-Elamio written by Sami Sharif and Imen Mansour: this book is composed of eight chapters. In Chapter One, the authors talk about the press language. Then, they propose issues about writing, language of radio and newspaper language.

3. Methodology
This study was conducted via descriptive-analytical and comparative approach. In order to recognize the characteristics of press language and show structural differences of journalistic texts in newspapers and journals, some excerpts of various newspapers in Jordan have been extracted and explored during the years 2000-2020. Mostly they belong to the editorial or leading article of the newspaper that is written by the editor. The index for choosing the press samples was principles of Arabic grammar.

6. Conclusion
The results of the study can be summarized below.
A kind of sincerity has been created between the author and the reader so that the author speaks the reader's mind. Hence, the press language has propelled toward simplicity and sincerity and it is far from formalities.
In recent years, the press authors are anonymous people who are shaped in the heart of the press and have press identity. They owe their popularity to the press.
One of the characteristics of the press in recent years is that they are free of figures of speech and imagery and transfer the subject in the shortest time and the most convenient form.
Today, degree of importance and ups and downs of the subject determine the form and shape of lines of a journalistic text. In recent years, journalistic texts have become personalized and proceeded toward specificity.
Slang and Arabicized words are nowadays used in journalistic texts. Moreover, the press language has gradually inclined toward colloquial language, because the authors believe that the journalistic text must be alive and dynamic and improvised.
 

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The use of recycled materials in Portland cement concrete (PCC) has become more and more popular in recent years. Most recycled materials applied in PCC are used to replace coarse aggregates, fine aggregate, or act as cementitious additives. When using recycled materials in PCC, it is desirable that the properties of the concrete can also be improved. Plain PCC, while typically having high strength, generally possesses very low post failure toughness, which may cause abrupt failure of structures and short pavement life. Reclaimed or recycled asphalt pavements (RAP) have been routinely used in the construction of pavement granular bases and hot-mix asphalt concrete. RAP is the removed and/or processed asphalt pavement materials containing both aged asphalt and aggregates. The asphalt coated on the surface of the aggregates typically forms a film with a thickness between six to nine microns. The use of RAP in PCC, though seems to be a viable solution to improve the toughness, has received little attention by research communities. Cementitious systems incorporating polymers have received considerable inter- national attention, especially over the last 30 years or so. The reason for this interest can be attributed to the improved engineering properties when compared to the unmodified materials, e.g. tensile/flexural strength, toughness and durability, the latter including resistance to carbonation, chloride penetration, and frost damage. Additionally, these systems may be used as repair materials where a good bond with the existing concrete or steel is required. Many polymer concrete combinations are available. Polymer-modified cement mortar and concrete (PMC): polymer particles in the form of a latex or redispersible powder are added to a fresh cementitious mix which is then cured. The most commonly used latexes are aqueous suspensions of styrene- butadiene-rubber (SBR) and various acrylics (Ac) containing 45±50% polymer solids. In SBR, the ratio of styrene to butadiene governs the properties of the polymer, with 60±65% styrene giving a good balance. Higher styrene contents would improve compressive and tensile strengths but reduce adhesion and raise the minimum film-forming temperature (MFT). In this study, the effect of SBR latex and silica fume on the mechanical strength (compressive, bending, and splitting tensile strength, elasticity modulus, toughness index), permeability (water penetration, rapid chloride penetration (RCPT), electrical specific resistivity) and microstructure of concrete made with recycled asphaltic aggregates to replaced with natural coarse aggregate (33%, 66% and 100% by weight) were studied. Results showed that the adding of latex and silica fume significantly increased mechanical strength and decrease permeability of concrete mixes. quality and microstructure of interfacial transition zone (ITZ) between aggregate- cementitious matrix by use of scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy analysis (EDX) was evaluated. SEM images showed that the mixtures containing latex and silica fume had uniform and smooth structure at surface aggregate- cementitious matrix, and also EDX analysis represents reducing the thickness of ITZ and the calcium to silicon ratio. For assessment of latex effect mechanism on compressive strength, three different type of curing on cube mixtures were applied. The results showed that compressive strength of specimens cured at temperatures significantly increased, which indicates of heating- help to formation polymeric membrane in specimens containing latex.

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Various studies on cars aerodynamics focusing on the Ahmed body model as a standard and simplified shape of a road vehicle have been carried out in recent years. In this paper plasma actuator as an active flow control method has been employed to control flow around the rear part of an Ahmed body with the rear slant angle of 25°. Experiments performed in a wind tunnel in free stream velocity of U=10m/s using steady and unsteady plasma actuator excitations. Pressure distribution on the rear part was measured by 52 sensors, and also total drag force was extracted by a load cell. More over smoke flow visualization was carried out to determine the flow pattern around the body. The results showed that employing plasma actuator not only has an effective influence on pressure distribution on the rear slant surface, but also reduces total drag force in steady and unsteady excitations 7.3% and 5%, respectively. As a result, based on flow visualization and pressure distribution tests, plasma actuator in steady state actuation, could distract D-shape vortices and suppress the separated flow over the rear slant.

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Airports are one of the most vital infrastructures of any country, which play an important role in transporting cargo and passengers to different parts of the world. The preservation and optimal use of airport resources and assets is one of the main goals of airport managers. On the other hand, airlines have a special concern on saving time, fuel consumption, maintaining passenger satisfaction, and so on. One of the most important resources in the world's major airports are the gates of the passenger terminals of airports, which have an undeniable aspect in the better performance of the airport. The assigning of aircraft to these gates has long been a concern for researchers in operations research as well as air transport activists. This research deals with the issue of assigning aircraft to the passenger terminal gate. The problem of optimal gate assignment is a complex issue and requires consideration of many parameters and variables in order to achieve the desired result. In this research, it’s tried to solve the gate allocation problem by presenting a suitable model. Providing an appropriate linear model is one of the main challenges of the problem. A special attention has been paid to the issue of safety. Therefore, by applying safety restrictions, a suitable model is provided. The main purpose of this study is to minimize the scatter of idle (lost) gates while not preventing mismatch between flight size and gate and also justifying safety needs. These cases are assigned and examined in the framework of the optimization model in this research. To solve such problems, which are usually not possible by manual calculations or are very time consuming, the metaheuristic algorithms are used. Since because NP-Hard nature of problem, it is very time consuming and difficult in the usual way. Therefore, this study tries to provide an efficient and fast way to solve the gate assignment problem. In the proposed method, first all the sentences of the objective function were considered as, then all were divided into two categories of hard and soft constraints. On the other hand, in the model of the basic method, the power of two terms in the objective function is used. The proposed model was modified. In the end, it was tried to modify the terms of the objective function and constraints in such a way that in addition to meeting the expectations and constraints of the problem, it allows the use of two flights from the same gate (MARS effect) to increase resource efficiency. The method is based on a genetic algorithm that includes the initial population, selection, combination or mutation, generation of a new offspring, and re-selection. In this study, 5 scenarios with various flights and gates have been used. The improvement of total idle times in the first scenario was 72.75%, in the second scenario 76.92%, in the third scenario 82.38%, in the fourth scenario 82.38% and in the fifth scenario 79.67%. All of results. Show the efficiency of proposed model.