Sharif Digital Repository

The picosecond (ps) pulses in a synchronously pumped optical parametric oscillator (SPOPO) is generated by a 20W and 81.1 MHz Yb fiber laser at 1064nm, providing 11.7 W of total average power in near to mid-IR at 73% efficiency so that the signal pulse with a wavelength of 1560 nm and 7.1W average power and 3330 nm idler pulse with an average power of about 4.6W has been produced. The optical parametric oscillator (OPO), based on a 50 mm MgO:PPLN crystal with 5 gratings which is capable of withstanding large average powers without thermal effects.
The duration of these ultrashort infrared signal pulse generated by the described SPOPO is measured by using homemade interferometric... 

In recent years, requirement engineering and goal modeling have gained more attention among different organisations. Therefore, different methods have been designed to discover stakeholders’ requirements and translate them into process and organizational goals. Various goal models have been introduced to represent these goals and their relations towards each other. Still, these methods are manual representations of different process scenarios and do not relate to the actual behavior. In 2014, Map Miner Method (MMM) was introduced to discover intentional process models from event logs. MMM uses Hidden Markov Model (HMM) as a means to represent the process as a map model of strategies and... 

Recommending routes to city taxis in order to improve their performance in finding passengers can reduce traffic, pollution and waiting time for passengers, as well as this, increasing the efficiency of taxis can increase their income. In this study, by analyzing trajectory data obtained from 536 taxis in San Francisco over a period of one month, we generated networks of cells, each of which has time-dependent characteristics such as the probability of finding a passenger, the capacity of each cell, or the amount of demand exists is in the cell and the average speed of passing through that cell. also, the connections between these cells in order to make more use of the experiences of taxi... 

Michael Zimmerman in his book Living with Uncertainty has objected to two views of moral obligation, namely objective and subjective view. Two overcome these problems he suggests a third view which he calls prospective view and tells us that our moral obligation is determined by the prospection that each of our choices give us. In this thesis first I review Zimmerman’s objections to objective and subjective view. Then I try to suggest a solution for the objective view  

This dissertation consists of three chapters. In the first chapter, a description of formation of Darwin's theory of Evolution is expressed. After that, the process of formation of modern theory of Evolution, along with an explanation of the theory of evolution and the evidence for it was mentioned. In the second season, which is responsible for the scientific study of the theory, at some point the evidence of this theory has been reviewed. After that, some of the challenges raised against this theory have been studied. The major scientific challenges described in this chapter is based on recent advances made in biology, based on that, the mechanism of theory can’t explain the complex... 

In Naming and Necessity and Identity and Necessity, Kripke convinced many that there are necessary propositions which are knowable only a posteriori. Kripke’s examples of these propositions can be placed into three categories: 1) Some mathematical propositions like Goldbach’s conjecture (the conjecture that every even integer greater than 2 can be expressed as the sum of two primes) 2) Scientific truths like “Water is H2O”, “Gold has the atomic number 79”, etc. 3) Identity statements flanked on both sides with proper names; like “Hesperus is Phosphorus”, “Cicero is Tully” and the like (in the rest of this article, these three categories will be called, respectively, the first, the second and... 

In his Mind, Brain and Free Will, Swinburne introduces a new argument for substance dualism based on the synchronic unity of humans’ conscious experiences. He argues that the human body cannot be the substance of such a synchronic unity, and that this coexperiencing property, which is a mental property, is the essential property of the human substance: hence our substance is a mental substance. After providing a careful explanation of Swinburne’s subtle argument, I first try to demonstrate that it is metaphysically possible that the brain itself could instantiate such a synchronic unity without the need to presume another substance. Then I shall argue that it is unclear how to infer the... 

Wilfrid Stalker Sellars (1912-1989) is an analytic philosopher whose philosophy is famous for being deep, systematic and extremely influential and notorious for being difficult to read. Although he has many original and interconnected ideas in different branches of philosophy- including metaphysics, epistemology, philosophy of mind, ethics, philosophy of language and meta-philosophy- the place of science in his system is completely indispensable. In his meta-philosophy, Sellars defines his philosophical project as an attempt to reconcile two distinct world-views of humanity in the modern word; scientific image and manifest image. Approaching Sellars’ philosophy by placing science at the... 

Semantic Holism is one of the most effective and wide spreading topics in philosophy of language. W.V.Quine with his “Two Dogmas” article has coined semantic holism with his name. After Quine, semantic holism absorbed many attentions in the philosophy of language and also other fields. Even, in neural networks and artificial intelligence, holistic presumptions about meaning are accepted. Nevertheless, arguments for meaning holism and their validation has not tended enough. Fodor and Lepore, in Semantic Holism; A Shopper’s Guide, are trying to reconstruct arguments for semantic holism that had been presented by philosophers like Quine, Davidson, Dennet, Lewis, and Churchland and then... 

The debate over the nature of perceptual states has been a significant part of the literature of philosophy of the mind during the past two decades. John Campbell's philosophical works on metaphysics and epistemology of sensory perception, according to many of his followers and critics, are among the most coherent contemporary philosophical works with recent advances in cognitive science. His research on the relationship between attention, reference, knowledge and spatial representations is to a large extent supported by scientific ideas in empirical psychology, and it can be said that most of his work is devoted to analyzing and solving the theoretical complexities deriving from empirical... 

This Thesis identifies the pattern of technological learning in developing complex products systems (CoPS). The experiences of Iran in missile development in the defense industry has been studied to explain the learning process in attaining indigenous technological capability. The case study of TOW missile development including international technology transfers has been explored to investigate the technological learning patterns. The role of policy initiatives had excessive importance through technological learning in the case study  

One of the important problems in the history of philosophy of Mind &Science is to respond this question: whether our observations which are the basics of our experiences are theory laden or not? theory-ladenness of observation thesis has been endorsed by Duhem and hansen and thomas kuhn,generally theory-ladensess of observation devide in two concepts, firstly it means the affection of on the observable terms secondly it relates to the affection of theories on our perception and phenomenology of experience. fodor claims that theories has nothing to do with our observation and churchland claims vice versa, both of these philosophers mention their own reasons and in this thesis we are looking... 

Technological capabilities as one of the growth’s aspects in developing countries have gained focus for research in last years. This study attempt to analyze the pattern of technological capabilities in four different sectors including Optic, Aerospace, Pharmaceutical and Biotechnology. In each sectors four Iranian companies as the case studies are selected. After deep interviews with key people in each company, required data is gathered. Data in each company is analyzed. The results of analysis for companies in one sector are gathered for analyzing each sector. In order to evaluate technological capabilities, the time required to improve, lead-lag relationship for gaining higher levels of... 

The idea that the intentional states are essentially normative has been much discussed in the philosophies of mind and cognitive sciences in the past few decades. The main idea is that some norms are essentially engaged in constituting the nature of the intentional states. Reaching an accurate formulation of this thesis and arguing for and against it has sparked much disagreements among the proponents and the opponents alike. This dissertation makes the case for a particular version of this thesis, according to which the intentional states, particularly beliefs and intentions, are construed as theoretical and practical commitments. This is the view which has already been defended by several... 

Among fundamental metaphysical quests, one might wonder: Why is there anything at all rather than just nothing? Many contemporary thinkers reject that question because they think it is meaningless, trivial, or necessarily unanswerable. So, most of them view the world’s existence as a brute fact. But I provide reasons for thinking that the Why question could make sense and one might even expect an answer to it. I begin by showing that the Why question could meaningfully ask why the world is not empty of all concrete things. One might regard this question as important if one accepts that it is, in some sense, possible for all concrete things to vanish, one-by-one. Next, against the traditional... 

When we talk about something being normative, it means that there are do’s and don’ts specific to that thing. When we say that language is normative, it means that it is governed by do's and don'ts and we cannot use linguistic structures arbitrarily. In other words, we have justifiable modes of linguistic use that failing to accord with them will distort the meaning of the propositions in the language. In the field of ethics, it may be easier to comprehend the concept of normativity. We all are in touch with ethics and ethical propositions in our daily lives. Beyond this bond, it seems that there is a kind of necessity for us. It seems that because of this necessity, acting in accordance... 

After Hume’s skeptical argument on the concept of causality and establishing the regularity theory of causation by him, it seemed that the regularity theory might not respond to irrelevance problems and spurious regularities. In the second half of the twentieth century, attempts were made, e.g. Hans Reichenbach's proposal of the “common cause principle,” for solving the problems of regularity theory which resulted in probabilistic approach to causal relationships. The importance of the common cause principle is that it has inspired the “Causal Markov Condition” which is the most fundamental condition for causal networks. The causal Markov condition states that a variable X is... 

One of the important issues in the philosophy of mind is the challange about the content of mental states, how the mind can refer to the world. To explain this special relationship that is not observed in the physical world, various mental models have been implemented, one of which is the connectionism model. Connectionist networks are based on the idea of biological neural networks, and the main concern of connectionism is modeling the brain and implementing human mind characteristics. The connectionist model was proposed by emphasizing the necessity of linking symbols with their original content and meaning. In this model, data representation is done in a holistic way and based on network... 

Has technology been able to increase human happiness(well-being)? An important question that is difficult to answer, in this thesis, we will try to identify different angles of happiness theories, then we will reach conclusions based on the friction of people's happiness in the society. The two main results will be that the physical dimension of happiness has little effect on human happiness compared to the psychological dimension of happiness, and we will get this result in positive psychology. Second, paying too much attention to the physical dimension is harmful even for human happiness, and then in the third chapter, based on the obtained criteria, we will go to measure technology and...