فهرست مطالب seyed hossein

In current study, an integrated guidance and control system is assessed for a projectile having dual spin motion in the cascade control structure. In this way, a nonlinear seven degrees of freedom model is used and coupling effects of pitch and yaw channels is taken into consideration. Based on cascaded control structure, a three-loops controller is designed, which in inner and middle loops the dynamic inversion method is used, and in the outer loop, an adaptive model based on PID controller is designed. The dynamic pressure contribution in acceleration command is also taken into account. The performance of the designed guidance and control system is assessed in presence of uncertainties via Monte Carlo statistical simulations. The results of suggested algorithm are compared with that of a cascade control having a classic PID controller in its outer loop. The results show the superior performance of the proposed algorithm in achieving the target and control effort.

Virtual training (electronic) as one of newfound developments of information and communication is a powerful tool for improving quality and efficiency of training. This research studies the possibilities of rural and nomadic schools to answer the question of whether a virtual education system can be set up for nomadic and rural students.This study has been performed with the aim of the feasibility of the establishment of virtual training in the framework of six components including hardware infrastructure, software infrastructure, cultural activities, electronic content, financial resources and support system, and specialized human power in high school of rural and nomadic areas in Lorestan province. In this study, descriptive-survey research method has been utilized. Statistical society consists of 1223 teachers, FAVA (Information and communication technology) experts and scopes of high school of rural and nomadic areas in Lorestan province, of which 292 persons were chosen by Morgan table. The information collection tool was researchist-made questionnaire.
Data Analysis was performed on two levels of descriptive and inferential statistics, and also confirmatory factor analysis was done by SMARTPLS2. Our findings showed that the studied society is ready to deploy virtual training in terms of software and hardware infrastructures. However, it is not possible to establish virtual training with respect to moderately specialized manpower, cultural activities, financial resources and support system and electronic content. Eventually, according to the terms it is not feasible to deploy virtual training in high school of rural and nomadic areas in Lorestan province.

The Bird symbol has a special place in the literature of various nations. This symbol is also manifested in the mirror of contemporary Arabic literature. Arab poets and writers use symbol as a means of criticize of disorganized situations of society for various reasons.This paper aims to explain the symbol concept and the factors that lead the works of contemporary literature to be symbolic, and decodes the one of Muhammad al Maghut by using descriptive analyses method. "Humpbacked Bird" ; as the name implies; is purely symbolic work that involves the political, social and cultural themes. One of the most important symbols that used in this drama , is sparrow, which is more frequent than other symbols. This symbol is present from beginning to end of drama and often it has different meanings and sometimes opposite cases and the end , overcome the positive means of bird to negative means of that. That is one of important results of this research.

Although none of the concepts of form as following function or form as a purely semiological order or the necessity or otherwise of taking the context into account in design are new in architecture today, it is still hard to create any remarkably thoughtful architecture without having answers to such questions. The present text is an exploration of the high-rise, gate-like twin tower type: a type without a significant historic precedent, and as such, relatively free from post-design semiological loads despite the limited numbers of its examples. Having Jim Collins’s idea of the replacement of ‘form follows function’ with ‘value follows location’, the text attempts to demonstrate that even in the case of this type in which close associations between design ideas and semiological references are not far away, one can still witness a fluidity in the relationship between form and function on one hand, and form and socio-political and cultural context on the other. In other words, it is not just the classic views on typology whose historicist and rationalist traditions seem inadequate to explain this type, but also that neither the earlier idea of form following function nor the latter one of the building as a meaning-producer and a conveyor of semiological references can provide a firm ground in this regard.

The question of whether architectural creativity is more of an artistic or engineering nature is one with a long history but also one with no conclusive answer. The art camp would argue that technology should be treated as a means towards and end، and that technology alone cannot give meaning to our lives. The engineering camp on the other hand would argue that good problem-solving results in better ways of living our everyday lives، and that this in turn brings about a beauty of its own which is beyond that offered by conventional aesthetics of beautiful objects. This dichotomy، among other things، epitomises the inconsistent relationship between architectural design value systems and those of other arts; for although they share certain concepts about beauty and the role of each discipline’s creative products in enhancing their audiences’ and users’ lives، the influence of other ‘outside’ disciplines on architecture and other more applied arts can have an effect on diverting their value systems. Put differently، architectural value systems do not consistently parallel those of other arts. This paper looks at some key moments in modern architectural history to show the degree to which architectural value systems share—or otherwise—the values of the other arts and then extend the survey to the present-day emergence of environmental ethics in architecture. It argues that the factual، non-ideological sound of environmental ethics may be promising، but it also signals the arrival of another period of drifting architectural and artistic value systems: one in which، perhaps not for the first time، the ethical is not invested in any kind of semantics and aesthetics of the product itself، but in the processes of its formation and، importantly، in the lifeenhancing possibilities of the work.

Aortobronchial fistula (ABF) is a rare and late complication of cardiac surgery. If untreated, mortality rate is approximately 100% secondary to exsanguinations haemoptysis. Early diagnosis and treatment are essential for successful management. Open surgical repair is associated with high morbidity and mortality rate, ranging from 25% to 41%. Endovascular treatments of ABF is a less invasive treatment modality and have become an important alternative to open surgical intervention in aortic pathologies. We present a case of ABF that successfully is managed by endovascular approach.