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Modelling Weather Index Based Drought Insurance For Provinces In The Central Anatolia RegionEvkaya, Ozan Omer 01 August 2012 (has links) (PDF)
Drought, which is an important result of the climate change, is one of the most serious natural hazards globally. It has been agreed all over the world that it has adverse impacts on the production of agriculture, which plays a major role in the economy of a country. Studies showed that the results of the drought directly affected the crop yields, and it seems that this negative impact will continue drastically soon. Moreover, many researches revealed that, Turkey will be affected from the results of climate change in many aspects, especially the agricultural production will encounter dry seasons after the rapid changes in the precipitation amount. Insurance
is a well-established method, which is used to share the risk based on natural disasters by people and organizations. Furthermore, a new way of insuring against the weather shocks is designing index-based insurance, and it has gained special attention in many developing countries. In this study, our aim is to model weather index based drought insurance product to help the small holder farmers in the Cental Anatolia Region under different models. At first, time series techniques were applied to forecast the wheat yield relying on the past data. Then, the AMS (AgroMetShell) software outputs, NDVI (Normalized Difference Vegetation Index) values were used, and SPI values for distinct time steps were chosen to develop a basic threshold based drought insurance for each province. Linear regression equations were used to calculate the trigger points for weather index, afterwards based on these trigger levels / pure premium and indemnity calculations were made for each province separately. In addition to this, Panel Data Analysis were used to construct an alternative linear model for drought insurance. It can be helpful to understand the direct and actual effects of selected weather index measures on wheat yield and also reduce the basis risks for constructed contracts. A simple ratio was generated to compare the basis risk of the different index-based insurance contracts.
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Construction Of Substitution Boxes Depending On Linear Block CodesYildiz, Senay 01 September 2004 (has links) (PDF)
The construction of a substitution box (S-box) with high nonlinearity and high resiliency is an important research area in cryptography.
In this thesis, t-resilient nxm S-box construction methods depending on linear block codes presented in " / A Construction of Resilient Functions with High Nonlinearity" / by T. Johansson and E. Pasalic in 2000, and two years later in " / Linear Codes in Generalized Construction of Resilient Functions with Very High Nonlinearity" / by E. Pasalic and S. Maitra are compared and the
former one is observed to be more promising in terms of nonlinearity. The first construction method uses a set of nonintersecting [n-d,m,t+1] linear block codes in deriving t-resilient S-boxes of nonlinearity 2^(n-1)-2^(n-d-1),where
d is a parameter to be maximized for high nonlinearity. For some cases, we have found better results than the results of Johansson and Pasalic, using their construction.
As a distinguished reference for nxn S-box construction methods, we study the paper " / Differentially Uniform Mappings for Cryptography" / presented by K.Nyberg in Eurocrypt 1993. One of the two constructions of this paper, i.e., the
inversion mapping described by Nyberg but first noticed in 1957 by L. Carlitz and S. Uchiyama, is used in the S-box of Rijndael, which is chosen as the Advanced Encryption Standard. We complete the details of some theorem and
proposition proofs given by Nyberg.
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Παλαιογεωγραφική εξέλιξη της ευρύτερης περιοχής Μοδίου – Πόρου / Palaeogeographic reconstruction in the wider region Modi rocky islet and Poros islandΠρεβένιος, Μιχαήλ 14 February 2012 (has links)
Οι μεταβολές της στάθμης της θάλασσας τα τελευταία 20.000 χρόνια και η εμφάνιση καταστροφικών φαινομένων (σεισμοί, παλιρροιακά κύματα) έχουν οδηγήσει στην καταβύθιση αρχαίων πόλεων, οικισμών και λιμενικών εγκαταστάσεων. Οι περισσότερες των αρχαιολογικών παράκτιων θέσεων σήμερα, βρίσκονται βυθισμένες στη θάλασσα και η μελέτη τους απαιτεί τη χρήση σύγχρονων συστημάτων θαλάσσιας γεωφυσικής διασκόπησης. Τις τελευταίες δύο δεκαετίες οι θαλάσσιες γεωφυσικές μέθοδοι έχουν αναδειχθεί σε εξαιρετικά αποτελεσματικό μέσο στη μελέτη τέτοιων περιοχών καθώς είναι εφικτό: (α) να εντοπίζουν και να χαρτογραφούν με ακρίβεια και σε σύντομο χρονικό διάστημα μεγάλης έκτασης περιοχών αρχαιολογικής σημασίας, (β) να εντοπίζουν και να χαρτογραφούν γεωμορφές σχετιζόμενες με το περιβάλλον ανάπτυξης των αρχαιολογικών θέσεων έτσι ώστε να αναπαριστούν την εξέλιξη της παράκτιας παλαιογεωγραφίας. Επιπλέον, οι γεωφυσικές μέθοδοι χρησιμοποιούνται πλέον συστηματικά για τον εντοπισμό και τη μελέτη κινητών μαρτυριών (ναυάγια) της ανθρώπινης δραστηριότητας στον πυθμένα.
Στην παρούσα εργασία παρουσιάζονται τα προκαταρκτικά αποτελέσματα από την εφαρμογή των μεθόδων θαλάσσιας γεωφυσικής διασκόπησης στην ευρύτερη περιοχής Μοδίου – Πόρου. Στη βορειοδυτική πλευρά της νησίδας Μόδι, το Ινστιτούτο Ενάλιων Αρχαιολογικών Ερευνών (ΙΕΝΑΕ) εντόπισε φορτίο ναυαγίου που χρονολογείται τον 12ο αιώνα π.Χ. Επιπλέον, η περιοχή μελέτης αποτελεί μεγάλο αρχαιολογικό ενδιαφέρον για τον Ελληνικό θαλάσσιο χώρο διότι στην αρχαιότητα αποτελούσε σημαντικό εφαλτήριο και βρίσκονταν σε ενδιάμεσους πολυσύχναστους θαλάσσιους πλόες του Αργοσαρωνικού κόλπου.
Τα όργανα γεωφυσικής διασκόπησης που χρησιμοποιήθηκαν στην συγκεκριμένη έρευνα ήταν o τομογράφος υποδομής πυθμένα υψηλής διακριτικής ικανότητας και ο ηχοβολιστής πλευρικής σάρωσης.
Η επεξεργασία και η ανάλυση των δεδομένων επέτρεψε την αποτύπωση της θέσης του ναυαγίου με σύγχρονες μεθόδους διασκόπησης, την κατασκευή λεπτομερών χαρτών βυθομετρίας και γεωμορφολογίας του πυθμένα, τον εντοπισμό ιχνών (scarps) καταβυθισμένων παλαιοακτών και τον προσδιορισμό της στρωματογραφικής υποδομής του πυθμένα στην περιοχή μελέτης. Με βάση τα παραπάνω δεδομένα έγινε προσπάθεια ανάπλασης της παλαιογεωγραφικής εξέλιξης στην ευρύτερη περιοχή μελέτης για τα τελευταία 18.000 χρόνια. Επιπλέον εντοπίστηκε στην ευρύτερη περιοχή έρευνας, ένας σημαντικός αριθμός στόχων πιθανής αρχαιολογικής σημασίας. / The changes in sea level over the last 20,000 years and the emergence of catastrophic events (earthquakes, tidal waves) have led to the submergence of ancient cities, settlements and port facilities. Most of the archaeological coastal positions today are immersed in the sea and their study requires the use of modern systems of marine geophysical surveys. Over the past two decades, marine geophysical methods have become an extremely effective tool in studying such areas as practicable: (a) to identify and map out accurately and in a short period of large areas of archaeological importance, (b) to identify and mapping landforms associated with the development environment of the sites to represent the evolution of the coastal Paleogeography.
In addition, geophysical methods are now used routinely to detect and study mobile testimonies (wrecks) of human activity on the sea floor.
This paper presents preliminary results from the application of marine geophysical methods in the wider region Modi Rocky Islet and Poros Isl. On the northwestern side of the rocky islet of Modi, the Hellenic Institute of Marine Archaeology (H.I.M.A) identified a cargo of a shipwreck dating to the 12th century BC Furthermore, the study area forms great archaeological interest in the Greek sea area because in ancient times was an important springboard and was located in intermediar and frequented sea voyages of the Saronic Gulf.
The geophysical instruments used in this study was the subbottom profiler and side-scan sonar.
The processing and data analysis enabled mapping the location of the wreck using modern marine geophysical methods, build detailed bathymetry maps and maps with the geomorphology of the seabed, detect traces (scarps) of submerged palaeocoast and determine the stratigraphic infrastructure of sea floor in the study area. Based on these data attempted reconstruction of the palaeogeographic evolution of the study area for the past 18,000 years. In addition, in the study area, was identified a significant number of potential targets with archaeological importance.
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Lycia and Pamphylia under the Roman Empire from Augustus to DiocletianJameson, Shelagh January 1965 (has links)
No description available.
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Tombs and territories : the epigraphic culture of Lycia, c.450-197 BCRix, Emma May January 2015 (has links)
In this thesis, I look at the use of inscriptions on stone in the Lycian peninsula during the fourth and third centuries BC, considering the effect of internal and external events on the production of inscriptions in the area, and looking at aspects of continuity and change across the two centuries. In Chapter 1, I discuss the development of the Lycian alphabet, arguing that origins of the alphabet are far more complex than has usually been believed, and involved elements of both organic development and conscious devising of letters forms. Building on the work of earlier scholars, I consider the alteration of certain letters-forms over time, and use these - and other available indications of date - to allocated number of inscriptions from different sites to 'early' or 'later' periods; the results of this work are presented in the 'harts' at the back of my thesis. In the subsequent chapters, I build on my conclusions from the first chapter to discuss certain aspects of the epigraphy of Lycia in a broadly chronological fashion, first setting out the what we know about the historical background of each period under discussion, and then considering inscriptions of particular interest. In Chapter 2, dealing with the late-fifth and early-fourth century, I look at the earliest of the Lycian epitaphs, as well as the uniquely long inscriptions of the rulers of Xanthos. I consider the development and structure of the 'building formula' which is so common in Lycian inscriptions, and how this relates to other Anatolian epigraphy. Chapter 3 looks at the effect of the internal strife in early-third century Lycia, and particularly the figure of Perikle, on the epigraphic culture of Lycia, with particular discussion of the ẽnẽ ... Xñtawata 'ruler formula', while Chapter 4 discusses the changes brought about by Hekatomnid rule over Lycia, and the beginnings of the use of Greek in private epigraphy. Finally, Chapter 5 looks at the beginning of the Ptolemaic period, arguing that Lycian continued to be used in both official and private inscriptions, and discussing the ways in which official epigraphy became more similar to that of other Greek poleis - while retaining specifically Lycian features.
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The diaspora of Cypriot antiquities and the British Museum, 1860-1900Nikolaou, Polina January 2013 (has links)
This thesis examines the invention of Cyprus’ ancient history through the diaspora of Cypriot antiquities in the latter half of nineteenth century and the role of the modern museum in it (1860-1900). It maps the movement of the objects from their excavation sites, to their circulation in metropolitan museums and, finally to their display in museum galleries. In doing so this thesis explores the emergence of archaeology as a field-based discipline in the broader colonial, imperial and geopolitical context. The research of this project was conducted mainly at the Cyprus State Archives, the Greek and Roman Departmental Archives (British Museum), Dartmouth College Archives (NH). The first part of the thesis provides the theoretical framework in which this research is situated. Chapter 1 introduces the project, its research questions, its research questions and outcomes. Chapter 2 discusses the literature providing the main concepts that formed the arguments of this thesis. Chapter 3 contextualizes the diaspora of Cypriot antiquities within the broader history of archaeology and Chapter 4 overviews the methodology followed and the archival sources that were used for this project. The second part consists of my empirical work and maps the diaspora of the antiquities. It is thematically divided in three chapters. Chapter 5, Law, looks at the colonial and legal context of the excavation and exportation of the objects. Chapter 6, Excavation, discusses the every-day conduct of Cypriot archaeology in the field. Chapter 7, Circulation, examines the practices of collecting Cypriot antiquities, their exportation and circulation in metropolitan museums, and their display in museums (particularly in the British Museum). Chapter 8 brings the thesis into a conclusion and highlights the main findings and arguments of this project. The thesis explores the production, circulation and display of scientific knowledge regarding the ancient past of Cyprus by following the antiquities in their various forms (texts, impressions, photographs, objects). By following the objects’ social lives it addresses the issues of the circulation of scientific knowledge, of the criteria for asserting its authenticity and credibility and of the local/global nature of archaeological science. It will demonstrate that the methodological tenor of writing the objects’ biographies links the different scales of science’s making and illuminates its hidden stories, such as the practicalities of collecting in the field.
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Využití kovové aditivní technologie při výrobě oběžného axiálního kola turbínového motoru pomocné energetické jednotky / Application of Metal Additive Technology in Production of a Blisk for Turbine Engine of a Auxiliary Power UnitRobl, Jan January 2020 (has links)
The thesis deals with the possible use of additive technology in the production of strong thermally exposed components of turbine engines. The first part of the thesis is dedicated to the issue of processing heat-resistant materials by SLM method, introduction of conventional production of selected part and outline of currently used progressive methods in precision casting technology. These theoretical findings are further applied in the practical part of the thesis, which deals with the analysis of mechanical properties of cast and printed material IN 939. Experimental part also includes production of the blisk of the first stage turbine of the auxiliary power unit S5L by SLM additive technology. The thesis also includes analysis of fracture surfaces and metallographic analysis of samples using light and scanning electron microscopy. The thesis ends with the evaluation of the achieved results.
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Impacts Of Soil-structure Interaction On The Fundamental Period Of Shear Wall Dominant BuildingsDerinoz, Okan 01 July 2006 (has links) (PDF)
In many seismic design codes and provisions, such as Uniform Building Code and Turkish Seismic Code, prediction of fundamental period of shear-wall dominant buildings, constructed by tunnel form technique, to compute the anticipated seismic forces is achieved by empirical equations considering the height of the building and ratio of effective shear-wall area to first floor area as the primary predictor parameters. However, experimental and analytical studies have collectively indicated that these empirical formulas are incapable of predicting fundamental period of shear-wall dominant buildings, and consequently result in erroneous computation of design forces. To compensate for this deficiency, an effective yet simple formula has recently been developed by Balkaya and Kalkan (2004), and tested against the data from ambient surveys on existing shear-wall dominant buildings. In this study, previously developed predictive equation is modified to include the effects of soil-structure interaction on the fundamental period. For that purpose, 140 shear-wall dominant buildings having a variety of plans, heights and wall-configurations were re-analyzed for four different soil conditions classified according to NEHRP. The soil effects on the foundation were represented by the translational and rotational springs, and their rigidities were evaluated from foundation size and elastic uniform compressibility of soil. Based on the comprehensive study conducted, improved prediction of fundamental period is achieved. The error in predictions on average is about 15 percent, and lending further credibility to modified formula considering soil-structure interaction to be used in engineering practice.
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Pricing Power Derivatives: Electricity Swing OptionsAydin, Nadi Serhan 01 June 2010 (has links) (PDF)
The Swing options are the natural outcomes of the increasing uncertainty in the power markets, which came along with the deregulation process triggered by the UK government&rsquo / s action
in 1990 to privatize the national electricity supply industry. Since then, the ways of handling the risks in the price generation process have been explored extensively. Producer-consumers of the power market felt confident as they were naturally hedged against the price fluctuations surrounding the large consumers. Companies with high power consumption liabilities on their books demanded tailored financial products that would shelter them from the upside risks while not preventing them from benefiting the low prices.
Furthermore, more effective risk management practices are strongly dependent upon the successful parameterization of the underlying stochastic processes, which is also key to the effective pricing of derivatives traded in the market. In this thesis, we refer to the electricity spot price model developed jointly by Hambly, Howison and Kluge ([13]), which incorporates jumps and still maintains the analytical tractability. We also derive the forward curve dynamics implied by the spot price model and explore the effects on the forward curve dynamics of the spikes in spot price. As the main discussion of this thesis, the Grid Approach, which is a generalization of the Trinomial Forest Method, is applied to the electricity Swing options. We investigate the effects of spikes on the per right values of the Swing options with various number of exercise rights, as well as the sensitivities of the model-implied prices to several parameters.
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Discontinuous Galerkin Methods For Time-dependent Convection Dominated Optimal Control ProblemsAkman, Tugba 01 July 2011 (has links) (PDF)
Distributed optimal control problems with transient convection dominated diffusion convection reaction equations are considered. The problem is discretized in space by using three types of discontinuous Galerkin (DG) method: symmetric interior penalty Galerkin (SIPG), nonsymmetric interior penalty Galerkin (NIPG), incomplete interior penalty Galerkin (IIPG). For time discretization, Crank-Nicolson and backward Euler methods are used. The discretize-then-optimize approach is used to obtain the finite dimensional problem. For one-dimensional unconstrained problem, Newton-Conjugate Gradient method with Armijo line-search. For two-dimensional control constrained problem, active-set method is applied. A priori error estimates are derived for full discretized optimal control problem. Numerical results for one and two-dimensional distributed optimal control problems for diffusion convection equations with boundary layers confirm the predicted orders derived by a priori error estimates.
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