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Konut finansmanı ve Türkiye'ye uygun bir model önerisi
Full text linkOne of the main problems of developing countries is having difficulties in finding sources for housing finance. In order to solve housing finance problems of a country, institutional systems that have been structured according to its own economic and social conditions should be applied by the government. Through a well-designed and market-oriented system, it is easy to increase housing supply, as well as to construct advanced residences by transferring funds from the overbalanced sections to the deficient sections. Nevertheless, there must be a well-balanced relationship between government, financial foundations, house producers, insurance companies and households. The main purpose of this study is to propose an appropriate housing finance model designed based on Turkey?s current conditions. After discussions on housing finance systems, applied throughout the world, and learning some lessons from all, an appropriate housing finance model for Turkey has been proposed. Then, a feasibility project of this model has been tested by using valid data and making reasonable assumptions for the next ten years. At the end of this study, it is understood that housing finance model based on mortgage backed securities can be applied in the near future in Turkey. However, there are some requirements and regulatory needs must be fulfilled in many fields, such as in law of bankruptcy, tax regulations, law of banking and leasing, capital markets, and real-estate appraisal applications. Keywords: Housing finance, housing finance model, mortgage backed securities.Bir ülkenin konut finansmanı problemini çözmek için o ülkeye uygun kurumsal sistemler sunmak gerekmektedir. Ülkenin mevcut koşullara ve pazardaki gelişmelere odaklı geliştirilecek konut finansmanı sistemi sayesinde bir yandan nitelikli konut arzı artırılırken, diğer yandan da fon fazlası olan kesimden fon ihtiyacı olan kesime kaynak aktarımı sağlanarak konut sorununa çözüm bulmak mümkündür. Bu nedenle, konut finansmanı açısından devlet, finansal kuruluşlar, konut üreticileri ve hanehalkı arasında dengeli bir ilişkinin kurulması gerekmektedir. Bu çalışmada dünyada uygulanan konut finansmanı sistemleri incelenmiş, daha sonra Türkiye’ye uygun bir finansman modeli geliştirilmeye çalışılmıştır. Son olarak, sözkonusu modelin bir fizibilite projesi ile gerçek hayata uygulanabilirliği test edilmiştir. Anahtar Kelimeler: Konut finansmanı, konut finansmanı modeli, ipoteğe dayalı menkul kıymet
Doğu ve Güneydoğu Anadolu Bölgeleri'nin kentleşme sürecinin öncü kent döneminin ubaid ve uruk evreleri (M.Ö.5000-3100)
Full text linkIn this study it was tried to elucidate the Ubaid (5000-3900 B.C.) and Uruk (3900-3100 B.C.) periods of the Proto-Urban Period which is the first phase of the urbanisation process of the East and Southeast Anatolia Regions. Ubaid Culture of Southern Mesopotamian origin and which dates back to V thousand B.C. constituted the first cultural period of Proto-Urban Period, the first phase of initial stages in the urbanization process of East and Southeast Anatolia, which is defined in two stages: Proto-Urban and First Urban Periods. Uruk Culture, which is another South Mesopotamia culture and which dates back to second half of IV thousand B.C. These periods have been examined with historical background, social-political, economical and technological organization which are the factors affecting the urbanization, and then according to the institutionalised central authority, the high level of specialization, the prominent social stratification and the organised long-distance trade, which are the most important urbanistic characteristics peculiar to the urban settlements and the fundamental changes in the urban society. In this manner, it is tried to elucidate the Proto-Urban Period of the East and Southeast Anatolia Regions which are the initial/early stages of the urbanisation process of East and Southeast Anatolia Regions. And it is seen in the early stages of the proto-urban period, which is the first phase of the urbanisation process of the regions, the urbanisation process of these two regions is under the impacts of Ubaid and Uruk cultures which are the Southern Mesopotamian origin. But at the end of this period local Anatolian city model bearing same peculiaties begins to form in each regions. Key words: Urbanisation, proto-urban period, ubaid period, uruk period. Bu makalede, Doğu ve Güneydoğu Anadolu Bölgeleri’nin başlangıç evresi kentleşme sürecinin ilk aşaması olan Öncü Kent Dönemi’nin Ubaid (M.Ö.5000-3900) ve Uruk (M.Ö.3900-3100) dönemleri aydınlatılmaya çalışılmıştır. Bu dönemler kentleşmeyi etkileyen faktörler olan sosyo-politik, ekonomik ve teknolojik yapıları ve bir yerleşmeyi köy yerleşmesinden ayıran ve kent toplumlarının sosyal organizasyonundaki temel nitelikteki kentsel özellikler olan kurumsallaşmış merkezi otorite, yüksek seviyeli uzmanlaşma, belirgin sosyal tabakalaşma ve organize olmuş dış ticaret açısından incelenmiş ve bu dönem yerleşmelerinin niteliği ve bu bölgelerin kentleşme sürecinin başlangıç evresi olan Öncü Kent Dönemi’nin Ubaid ve Uruk Dönemleri’ndeki durumu irdelenmiştir. Anahtar Kelimeler: Kentleşme, öncü kent dönemi, ubaid dönemi, uruk dönemi
İstanbul'da Birinci Ulusal Mimarlık Dönemi Yapıları'nın kent bütünü içindeki yerinin değerlendirilmesi
Full text linkThe buildings of the First National Architecture Period in the Turkish architecture history dated between 1908 and 1930, begins from the beginning of the 20th century in İstanbul, which, starting from Westernization and continuing in Administrative Reforms (Tanzimat), have undergone a modernization program. These architects, applying classical western discipline to their plan diagrams fastidiously, have attached more importance to flashing and decoration programs instead of seeking new plans. Post offices, office blocks, piers administrative buildings, warehouses, apartment houses, schools and monuments take place in the building inventory of the period. Their structures, which generally create small Nationalist urban centers, are like small city planning attempts in a period when urban-architecture organization has been established. The fact that these attempts are not yet serious organizations can be explained by their evaluation as single products in the architecture of the era and by them being magnificent and costly buildings. Yet an effort developing in time can be worth mentioning. Being technically as successful as their western counterparts, these buildings also included elevators, electiricity, air conditioning, central heating systems, laundries, which were newly added to urban life. The development line of these buildings in Istanbul were broken with the change in the economic conjuncture and with the centre moving to Ankara, and construction of the buildings of First National Architecture Period, which could have found an area of expansion in within a conscious city planning organization have stopped. Keyword: National Architecture, Westernization, Administrative Reforms.Türk mimarlık tarihi yazımında 1908-1930 yılları arasına tarihlendirilen Birinci Ulusal Mimarlık Dönemi yapıları, Batılılaşma döneminden başlayarak Tanzimat’ın ilanı ile devam eden modernleşme programı çerçevesinde biçimlenişini sürdüren İstanbul’da 20. yüzyılın başında görülmeye başlar. Plan şemalarında batının klasik disiplinini özenle uygulayan bu mimarlar yeni bir plan aramak yerine cephe düzenlemesine ve bezeme programına daha çok önem vermişlerdir. Postahane, iş hanları, iskeleler, yönetim yapıları, depolar, apartmanlar, okullar, anıtlar bu dönemin yapı envanterinde yer alırlar. Genellikle küçük Ulusal’cı kent odakları yaratan bu yapılar kent-mimarlık organizasyonunun henüz yerleşmediği bir dönemde küçük şehircilik denemeleri gibidir. Bu denemelerin henüz ciddi organizasyonlar olmadığı yapıların bu dönem mimarlığında hâlâ tek ürün olarak değerlendirilmesi, gösterişli ve masraflı yapılar olmasıyla açıklanabilir. Yine de zaman içinde gelişen bir çabadan söz edilebilir. Anahtar Kelimeler: Ulusal Mimarlık, Batılılaşma, Tanzimat
Historical development of museum education
Full text linkMüzeler kurulduğu yıllardan itibaren eğitim amacını taşımışlardır. Ancak müzelerde eğitim toplum yaşamına, eğitim ve müzecilik teorilerine göre farklı dönemlerde farklı anlam ve roller üstlenmiştir. Bu çalışmanın amacı, müzelerde eğitimin gelişimini ana hatlarıyla tarihsel perspektif içinde değerlendirmektir. Müze bir kurum olarak Avrupa’da mevcut koleksiyonların ziyarete açılmasıyla ortaya çıkmıştır. Müzelerin halka yönelik eğitim misyonuyla kurulmaları, halka açılmalarıyla başlamıştır. 19. yüzyılda müze ve eğitim ilişkisi Endüstri Devrimi’nin etkileriyle gelişmiştir. Bu dönemde doğrudan eğitim amacıyla pek çok müze kurulmuştur. Müze eğitimi 19. ve 20. yüzyılın ilk yarısı boyunca izleyiciye bilgi aktarımı ve öğrenenin olabildiğince çok bilgiyi alması olarak görülmüştür. Fakat 20. yüzyılın ikinci yarısından başlayarak müzelerde eğitimin anlamı tamamen değişmiştir. Bu dönemde müze eğitiminde bilimsel yaklaşım önem kazanmıştır. Bunun en büyük etkenlerinden biri UNESCO ve ICOM gibi uluslararası organizasyonların kurulmasıdır. 20. yüzyılda müze eğitimine yaşanan diğer önemli bir gelişme, 1950’lere kadar daha çok okul gruplarına yönelik çalışmalara ağırlık verilirken, 1950 sonrasında yetişkin izleyiciye yönelik çalışmalara da önem verilmeye başlamasıdır. Günümüzde eğitim müzelerin temel işlevleri arasında kabul edilmekte; müze eğitimi insanların var olan bilgi, yetenek ve kişisel ilgilerine göre müze koleksiyonlarından deneyim kazanmalarını, kendi anlamlarını çıkarmalarını sağlama ve yaşam boyu eğitimlerine katkıda bulunma süreci anlamını taşımaktadır. Pek çok müzede eğitim bölümü diğer bölümlerden ayrı bir birim olarak yer almakta, farklı izleyici türlerinin ilgi ve ihtiyaçlarına göre formal ve informal eğitime katkıda bulun çeşitli eğitim etkinlikleri sunulmakta, değerlendirilmekte ve geliştirilmektedir. Anahtar Kelimeler: Müze eğitimi, müze eğitiminin tarihçesi, müzecilik.Museums are institutions which have educational aims since the first museums had been estab-lished. The meaning and role of the education in museums change according to life of the society which is formed by the artistic, scientific, technologic and social developments and theories of education and museology in different periods of time. The aim of this study is to explain the development of the museum education on the main lines with a historical perspective. Before modern museums developed, different societies preserved objects and collections they held important. Museums in the modern sense developed in Europe in the 17th century with the opening of private collections of courtiers and gentlemen to visit. Museums have been accepted among the most important institutions as the source of knowledge during the Age of Enlight-enment. These first museums were educational environments for the members of the bourgeois to learn their country and the world and to increase their level of knowledge. Education as a crucial museum function has been recognized as long as there have been public museums. The first public museum, the Louvre Museum, opened in 1793. It formed an integral part of the newly democratic state. After the opening of the Louvre museum a lot of public museums established in Europe. In these museums education carried a political meaning such as transferring the information and values determined by the government to educate the people as citizens. In the 19th Century the relation between museums and education was developed with the influences of the Industrial Revolution. In the latter half of the 19th century, as industrialization progressed, population moved to the cities, and science and industry reshaped life. Moreover, government increasingly took responsibility for social services and education. Museums were viewed as one type of institution among several ones that could provide education for masses. Many museums were established for direct and explicit educational purposes. Since the begin-ning of the 19th century the museums have been serving schools. Educational programs for children and school groups gained importance in the museum education, until the 1950's. The relation between the school and the museums especially developed after the 1950's. During the 19th century and much of the twentieth, education in museums was mainly understood as delivery of information to learners whose task was ab-sorbing as much as possible. But it has been completely changed since the twentieth century. At the second half of the 20th century scientific approach gained importance in the museum education. One of the most important reasons of this is the establishment of organizations like UNESCO and ICOM. The activities and publications of these institutions lead to establish international standards and to create the environment of discussion and sharing information in museum education. In the definition of museum declared at 11th General Conference of ICOM held on Copenhagen at 1974 education accepted one of the main functions of museums: A museum is a non-profit making, permanent institution in the service of society and of its development, and open to the public, which acquires, conserves, researches, communicates and exhibits, for purposes of study, education and enjoyment, material evi-dence of man and their environment. Another im-portant development in the museum education in the 20th century is the increasing importance of educational programs for adults. One of the main factors of this is the appearance of the concept of "lifelong learning". Since the mid-20th century the museum education discipline has been appeared in museum studies. Today, education in museums has been under-stood as the process which enables people to make their own meanings from museum collec-tions according to their existing knowledge, skills, background and personal motivation, and this provides them to develop their lifelong education. In many museums, education department takes place as an independent department, and many museums organize and present various educational activities according to the needs of different visitor groups such as children, adults, teenagers, etc. In Turkey the museum education has been developing for the last twenty years. Museum exhibitions are generally designed as object based without any educational purpose and there are very few numbers of educational programs in Turkish Museums. It is needed to develop the educational function, which will contribute to the education and culture of the public in Turkish museums.Keywords: Museum education, history of museum education, museum studies
Duality in noncommutative gauge theories
Full text linkKomütatif olmayan (noncommutative) uzaylar farklı çerçevelerde karşımıza çıksa da bu tip kuramların gittikçe artan bir şekilde çalışılması, bunların sicim kuramı ile olan yakın ilişkilerinin kurulması ile olmuştur. Komütatif olmayan uzaylar üzerinde tanımlanan alan kuramları sicim kuramının ayrışma (decoupling) limitinde ortaya çıkmaktadırlar ve bu tip kuramlar komütatif benzerlerinden farklı özellikler göstermeleri nedeniyle ilgi çekmektedirler. Bu şekilde komütatif olmayan ayar kuramlarından elde edilecek sonuçların sicim kurumlarının çeşitli özelliklerinin anlaşılmasında önemli olması beklenmektedir. Dual kuramlar bir fiziksel modelin iki farklı, fakat eşdeğer formülasyonunu tanımlarlar. S dualite olarak adlandırılan kuvvetli ve zayıf etkileşimli modeller arasındaki ilişki, birinden diğerine gidilerek bir fiziksel modelin farklı etkileşme bölgelerindeki özelliklerinin çalışılmasına imkân verir. Bu çalışmada biz komütatif olmayan U(1) ayar kuramında S dualiteyi inceleyeceğiz. Öncelikle komütatif olmayan U(1) kuramının duali için hamilton fonksiyonunun nasıl kurulabileceğini inceleyeceğiz. Dual kuramda uzay ve zaman koordinatları arasıda komütatiflik özelliğinin bulunmaması nedeniyle bilinen kuantizasyon yöntemleri ile bunun nasıl yapılacağı açık değildir. Ana (parent) eylem bu iş için uygun bir araç olmaktadır. Ana eylemde uygun değişkenlere göre hareket denklemleri çözülür ve bu çözümler ana eylemde yerine konulursa orijinal kuram veya onun duali elde edilebilmektedir. Ana eylemin bu tanımlaması dual Lagrange fonksiyonu kullanılmaksızın hamilton fonksiyonunun elde edilebilmesine imkân verir. Yöntem öncelikle normal (komütatif) durum için geliştirilecek daha sonra elde edilen sonuçlar komütatif olmayan duruma genelleştirilecektir. İkinci olarak komütatif olmayan U(1) ayar kuramı ve onun duali için hem Lagrange hem de Hamilton yoğunluklarında elektrik-manyetik dualite dönüşümlerinin nasıl tanımlanacağını göstereceğiz. Anahtar Kelimeler: Komütatif olmayan geometri, dualite, sicim kuramı.It is largely believed that spacetime structure differs from the usual definiton by going to the high energies or equivalently at small distances. This belief has been justified by using different approaches in different fields of the physics. However, noncommutativity of space coordinates arise in a natural way in string theory and appear as a consequence of the nonlocal property of the string. Noncommutative spaces emerge as a consequence of the quantization of worldsheet theory of the string, which is ending on a D-brane, in presence of a background magnetic field. This configuration leads to the noncommutativity of the open string coordinates at the end where they are attached to the brane and hence the worldvolume of the D-brane also becomes noncommutative. The effective physics on the D-branes in presence of a background field can be described either by a commutative gauge theory or by a noncommutative one. Seiberg-Witten proved that these two different descriptions arise from the same field theory with different regularizations. Since the physics does not depend on the regularization, theories obtained with different regularizations can be related to each other. Hence they have enabled to construct a map between these two descriptions by a field redefinition. This is a perturbative expansion of the noncommutative fields in terms of the ordinary fields with respect to the noncommutativity parameter. By using the Seiberg-Witten map one can pass from a gauge theory defined in terms of the noncommutative fields to a gauge theory in terms of the ordinary fields. Duality appears in several different contexts of physics. Dual theories provide two different but equivalent descriptions of the same model in the diverse interaction regimes by using in general, different fields. The relation between the fields is in general not known explicitly and in the most of the cases it contains nonlinear terms. Thus, knowing the explicit relation between the fields allows perturbative calculations in the variables of the original theory both in the strong and weak coupling regimes. In this work we deal with noncommutative U(1) gauge theory and its S duality. When the initial theory has a noncommutativity between the space coordinates, dual of that results in a time/space noncommutative gauge theory. These types of time/space noncommutative theories correspond to the certain configurations of the string theory. When there is a noncommutativity between time and space it is not obvious how to apply canonical quantization methods. In the ordinary case time variable is the evolution parameter of system however it is not clear what one means by the noncommutativity of time. Hence, Hamiltonian formulation of dual theory should be clarified. Parent action method is an appropriate tool to study dual theories. Parent action is constructed from the initial theory by a Legendre transformation with respect to the initial field and contains the dual field as a Lagrange multiplier. Starting from the parent action one obtains the dual theory by taking the variation of the parent action with respect to the initial field. On the other hand if one performs the variation with respect to the dual field obtains the initial theory. Hence it becomes possible to study the dual Hamiltonian bypassing the space/time noncommutative dual Lagrangian.This Hamilton formulation playes important roles in the D3-brane worldvolume theories. Secondly we investigate the electric-magnetic duality relations in the noncommutative U(1) gauge theory. Electric-magnetic duality exchanges the electric degrees of freedom of theory with the magnetic degrees of freedom. It also exchanges the electric charge quanta with the managnetic charge quanta.Electric charge quanta at the same time related to coupling constant of theory. Such a transformation, if it can be constructed, will map the strongly coupled electric degrees of freedom of theory to weakly coupled magnetic degrees of freedom of it. Hence different phases of the gauge theories can be investigated. We provide the electric-magnetic duality transformations for both the Lagrange and Hamilton densities. A well known property of the ordinary gauge theories is verified for the noncommutative U(1) gauge theory: Duality maps the Lagrangian to itself up to an overall minus sign and keeps intact the Hamiltonian of U(1) gauge theory. However, electric-magnetic duality transformation in configuration space is shown to be defined by a reversed one with respect to that of in phase space. Keywords: Noncommutative geometry, duality, string theory
The propagation of nonlinear Rayleigh waves in a layered elastic half-space
Full text linkBu çalışmada farklı bir homojen, izotrop nonlineer hiperelastik malzemeden oluşan sonlu ve düzgün kalınlıklı bir tabaka ile kaplı elastik bir yarım uzayda küçük ama sonlu genlikli genelleştirilmiş Rayleigh tipi yüzey dalgalarının yayılması incelenmiştir. Harmonik rezonansın olmadığı kabulu ile bir pertürbasyon metodu kullanılarak dalgaların self modülasyonunun asimptotik olarak bir Nonlineer Schrödinger (NLS) denklemi ile karakterize edilebileceği gösterilmiştir. NLS denkleminin bilinen özellikleri göz önüne alınarak denklemin soliton tipi çözümlerinin varlığı ve ortamı oluşturan malzemelerin nonlineer özelliklerinin dalga modulasyonu üzerindeki etkisi nonlineer tabaka-nonlineer yarım uzay, nonlineer tabaka-lineer yarım uzay ve lineer tabaka-nonlineer yarım uzay modelleri için gözlemlenmiştir. Analizde ayrıca sabit bir dalga sayısı k için tabaka kalınlığının çok ince olması durumunda, h→0 limiti altında, yani ince tabaka yaklaşımı altında NLS denkleminin katsayılarının davranışları analiz edilmiştir. Sayısal incelemelerde hipotetik malzeme modelleri yanında gerçek malzeme modelleri de kullanılmıştır. Anahtar Kelimeler: Rayleigh dalgaları, self modülasyon, Nonlineer Schrödinger denklemi (NLS).In this work, the propagation of small but finite amplitude generalized Rayleigh waves in an elastic half-space covered by a different elastic layer of uniform and finite thickness is considered. The constituent materials are assumed to be homogeneous, isotropic, compressible hyperelastic. Excluding the harmonic resonance phenomena, it is shown that the nonlinear self modulation of generalized Rayleigh waves is governed asymptotically by a nonlinear Schrödinger (NLS) equation. The stability of the solutions and the exictence of solitary wave-type solutions of a NLS are strongly depend on the sign of the product of the coefficients of the nonlinear and dispersion terms of the equation. Therefore the analysis continues with the examination of dependence of these coefficients on the nonlinear material parameters. Three different models have been considered which are nonlinear layer-nonlinear half space, linear layer- nonlinear half space and nonlinear layer -linear half space. The behavior of the coefficients of the NLS equation was also analyzed under the limit as h (thickness of the layer) goes to zero and k (the wave number) is constant. Then conclusions are drawn about the effect of nonlinear material parameters on the wave modulation. In the numerical investigations both hypothetical and real material models are used. Keywords: Nonlinear Rayleigh waves, self modulation, nonlinear Schrödinger equation (NLS)
Road generalization for car navigation map design
Full text linkCoğrafi Bilgi Sistemleri (CBS) uygulamalarında, fiziksel yeryüzünün farklı amaç ve ölçeklerdeki haritaların oluşturulması aşamasında veri yoğunluğundan kaynaklanan problemler çıkmaktadır. Bunların en önemlileri sonuç haritaların tasarımı sırasında görülen sunulacak olan verinin içerik optimizasyonu ve amaca uygun olarak görselleştirilmesidir. Fiziksel yeryüzünün farklı amaç ve ölçeklerde modellenmesi konusu CBS uygulamalarında ölçek seviyelerinin tanımlanması yöntemiyle çözülmektedir. Bu kapsamda her bir ölçek seviyesi için farklı içerikte haritalar oluşturulmaktadır. Çoklu gösterimler olarak da adlandırılan bu haritalar günümüzde tek bir olgunun ya da varlığın tek bir sistem içerisinde farklı boyutlarda (çözünürlük, ölçek, doğruluk, zaman vb.) bir çok defa modellenmesi, gösterilmesi ve kullanılmasını amaçlayan Çoklu Gösterim Veritabanları (ÇGVT) yaklaşımı ile modellenmektedir. ÇGVT yaklaşımının geliştirilmesiyle birlikte harita üretimi ve güncellenmesi sürecinin otomasyonu açısından da önemli sonuçlar elde edilmiştir. Araç navigasyonu uygulaması da farklı ölçek ve çözünürlükteki haritaları bilgi iletişim aracı olarak kullandıkları için ÇGVT uygulaması olarak kabul edilir. Günümüzde ticari olarak kullanılan sistemlerde farklı ölçeklerdeki navigasyon haritası tasarımı için gerekli olan genelleştirme işlemi, CBS uygulamalarına benzer bir şekilde, ölçek seviyelerinin ve her bir seviyenin içeriğinin önceden belirlenerek sisteme tanıtılması yöntemi ile gerçekleştirilmektedir. Bu yolla elde edilen haritalar bir çok ihtiyacı karşılamakla birlikte içerik, sunum ve üretim yöntemleri açısından geliştirilmelidir. Bu çalışmada araç navigasyon sistemleri için harita tasarımı konusunda ÇGVT yaklaşımını da göz önünde bulundurularak bir tasarım yapılmıştır. Bu kapsamda sistemin en detaylı bilgiyi içeren kullanım seviyesi için genelleştirme yöntemleri önerilerek bu yöntemlerin uygulaması yapılmıştır. Anahtar Kelimeler: Çoklu gösterim veritabanları, navigasyon, genelleştirme.Geographical Information System (GIS) is a multi disciplinary work so various users with various requirements use these systems. This situation complicates the organization of the data and increasing density of the data appears as a problem that is needed to be solved. Optimization of the map data and its visualization depending on the aim of the application are the other important issues related with data organization. Modeling the physical reality as multiple representations is provided by the use of zoom levels in GIS applications. Maps with different levels of detail are created for each zoom level. These maps are entitled as multiple representations and currently modeled based on Multiple Representational Databases (MRDB) approach, which is used to store the same real world phenomena at different levels of accuracy and resolution. The use of MRDB also provides the automation of the generalization and updating processes of the maps. Navigation, which aims at wayfinding especially in the foreign environment, is a fundamental human activity and an integral part of everyday life. Advanced navigation systems integrate positioning and communication techniques, digital mapping, computer and handheld device technologies to cover the aim of navigation application. In addition to the accuracy of the data used in these systems, efficient communication of the system based information with the user is also important for the success of the system. Maps are used for the communication of the information together with the use of multi media technologies supported by the system. Since navigation maps are the basic visual tools for information communication in car navigation systems, they should be designed depending on the aim of the application for increasing the efficiency of the implemented system. Map design for navigation purposes should be considered in terms of small display cartography, since navigation systems use small display devices as hardware. Small display map design requires additional constraints in comparison with traditional map design. The common aim of these maps is to communicate the optimal data on a small display media. This task requires a special map design process including the intensive use of the generalization methods. Additionally databases used to design navigation maps need systematic updates in the case of changes in road geometries or attributes. All requirements of navigation map design process coincide with the context of the MRDB. Generalization is certainly one of the most important issues of the cartography which is the science and art of visualization of world reality on paper, screen or similar media. Particularly researches on automated generalization, data base design for multiple representations with very huge amount of data currently became a research base of Cartography. Similar to GIS applications, current car navigation systems use predefined zoom level and selection strategy to generalize the map content for the use of different levels of representations. Although this method covers several needs of car navigation, its static structure on data derivation and visualization issues should be improved for the use of 3 dimensional and real-time navigation applications. These applications are the new trends of current navigation technology. In this study, current commercial car navigation products were examined depending on the methods that they used for map design. Design problems, which are related with generalization issues, of navigation maps were determined for large and small scale representations. Optimization of the road network was one of the main design problems for any kind of navigation maps currently in use. In this study, this problem was examined for large scaled maps of MRDB designed for navigation purposes. A route dependant generalization approach that will be used for optimizing road network data was proposed. This approach based on the idea of classifying the road segments of a road network in three classes depending on their geometrical relations with calculated navigation route. Therefore this approach is applied whenever a navigation route calculated and it gives different results for each application. After classifying the road segments, they are selected for representation depending on their determined classes. This approach, which enables the cartographer to generalize the road network depending on their geometries in addition to their attributes, is also implemented and a sample result were presented in this study. Keywords: Multiple Representational Database, navigation, generalization, GIS
Quantitative analysis of fluvial response to block rotation; Almacık Block case
Full text linkDoğrultu-atımlı fay sistemlerinde diri faylarla sınırlandırılmış kabuksal bloklar düşey eksenli rotasyona maruz kalırlar. Bu çalışmada fluviyal sistemlerin düşey eksenli rotasyona olan tepkileri ve bu tepkileri kullanarak rotasyonun yönü ve miktarı tanımlanmaya çalışılmıştır. Araştırma Marmara Bölgesi doğusunda yer alan Almacık Bloku üzerinde yapılmıştır. Almacık Bloku Kuzey Anadolu Fay Sistemi içinde sistemin kuzey ve güney kolları arasında yer alan tamamen doğrultu-atımlı faylarla sınırlanmış mercek şekilli tektonik bir bloktur. Çalışmada ilk olarak Almacık Bloku’nu sınırlayan diri faylar haritalanmış, bunların kinematik özellikleri, segmentasyonları ile aktivite sınıflamaları yapılarak blokun neotektonik özellikleri ortaya konmuştur. Bunu takiben blok üzerinde yer alan akarsu şebekesi ve havzaları üzerinde sayısal yükseklik modelleri ve coğrafi bilgi sistemleri kullanılarak Asimetri Faktörü ve Vadi Yönelimi analizleri yapılmıştır. Ayrıca blokları sınırlayan fayların uzun dönem kayma miktarlarına bağlı olarak blokların rotasyon miktarının belirlenmesine yönelik yeni bir yaklaşım (tanjant yaklaşımı) geliştirilerek Almacık ve Armutlu Blokları üzerinde uygulanmıştır. Asimetri Faktörü analizleri akarsu havzalarının asimetrilerini nicel bir şekilde ifade etmeye imkan verir. Vadi Yönelimi analizi ise havzaların kaynak ve ağız kısımları arasındaki genel yönlenmeyi gösterir. Ana akış yönlerini karakterize eden vadi yönelim çizgileri Almacık Bloku üzerinde yer alan tüm havzalar için çizilmiş ve bunların gül diyagramları yapılarak yönlenme yoğunlukları gösterilmiştir. Yapılan Asimetri Faktörü analizleri sonucunda blokun saat yönündeki rotasyonuna akarsuların tepki gösterdikleri ve bunun akarsuların havzalarında sağ yönlü asimetriye neden olduğu görülmüştür. Vadi yönelimi analizleri ise akarsu havzalarının da blokla beraber saat yönünde rotasyona maruz kaldığını ve Almacık Bloku’nun Kuzey Anadolu Fayı’na bağlı olarak En Geç Pliyosen-Günümüz zaman aralığında 20°-25º saat yönünde döndüğünü göstermektedir. Anahtar Kelimeler: Kuzey Anadolu Fayı, blok rotasyonu, fluviyal tepki.Block rotations are common in the strike-slip fault systems. Blocks delimited by right lateral strike-slip faults display clockwise rotations and blocks delimited by left lateral strike-slip faults display anti-clockwise rotations. This deformation has been determined by using structural and paleo-magnetic properties of the rocks. In this study, for the first time response of fluvial systems was considered to identify direction and amount of rotation. Since the fluvial systems are very sensitive against internal and external neo-tectonic deformations, they might be utilized in order to identify block rotations along with structural and paleo-magnetic data. This fluvial response approach is applied to the Almacık Block located east of the Marmara region. Almacık Block is delimited by active faults of the northern and southern strands of the North Anatolian Fault System and consists of rocks from Paleozoic to Eocene metamorphic, volcanic and sedimentary rocks. The block is displaced, uplifted and rotated in the neo-tectonic period. It is a east to west trending spindle shaped tectonic block with 80 km length and 18 km width. The main drainage divide of the block is close to southern flank and roughly parallel to the long axis. Top surface of the block is remnants of a paleo-surface. It preserves initial direction of the parent rivers of current drainage network. We proposed that if a drainage basin in an homogenous and isotrope media, its response to block rotation would give rise to asymmetry on the cross-section of the main valley of drainage basin. Of course this response depends on erosional capability of the basins and rate of rotation. Three models were proposed as 1-Erosion<Rotation; 2-Erosion=Rotation; 3-Erosion>Rotation. In order to test the models, two geomorphic indices were applied on the basins. They are Asymmetry Factor and Basin Azimuth Analysis. Asymmetry Factor is the first index that we applied in order to test existence of fluvial response to block rotation. It is usually used to identify tilting of footwall of normal dip-slip faults. In this study, it was used to quantify asymmetry of the basins instead of tilting. Surface measurements of the main basins and right half were used to calculate asymmetry factor. We applied this index to 55 different basins of northern catchment and found %77 right asymmetry and %23 left asymmetry whereas on 24 different basins of southern catchment display %83 right asymmetry and %17 left asymmetry. Those values are consistently proved that drainage basins response to block rotation as they response to other tectonic deformations. Basin Azimuth analysis were applied to identify amount of rotations. It is based on angular relationships between former and present fluvial systems to North Anatolian Fault System. It is generally known that former drainage system that is observed on the paleo-surfaces from south to north, roughly orthogonal to the North Anatolian Fault System. Following the initiation of the North Anatolian Fault in the area those former drainage systems were perturbated and younger drainage systems, like Mudurnu Valley, started to develope. In this analyze whole of the drainage system was primarily evaluated. The rose diagram of it indicates orientation between 10-20º. Since some margins of the block has different surface orientation this orientation values has to be checked out on margins especially orthogonal to North Anatolian Fault. The Mudurnu valley is the best place to test it and we evaluated to southern and northern slope of the valley. The northern slope of the valley coincides the Almacık Block southern slope of the valley coincides Kapıorman Mountain. Hence, we can compare behaviour of the drainage basins on two block of the fault. Rose diagram of the northern slope (Almacık Block) clearly indicates 20º-25°clockwise rotation of the block with respect to southern slope (Kapıorman Mountain) of the valley. Both results reveal that fluvial systems are sensitive to block rotation and Almacık Block is rotated clockwise about 20-25º since the North Anatolian Fault initiated between the latest Pliocene to Present. Keywords: North Anatolian Fault, block rotation, fluvial response
Earthquake loss assessment study for Zeytinburnu district
Full text linkİstanbul'da gerçekleşmesi beklenen depreme, en iyi şekilde hazırlanmak için afetin hangi bölgeleri, hangi tipteki yapıları en çok etkileyeceği ve bu afetin nasıl bir ekonomik bilanço çıkaracağını afet olmadan önce tahmin etmek gerekmektedir. Bu mekanizma dünya üzerinde deprem için sıklıkla kullanılmakta ve tatmin edici sonuçlar vermektedir. Hasar tahmini için en önemli bileşen, ilgili bölgedeki tüm olası senaryoları uygulayabilecek ve bu senaryoların ilgili bölge yapıları üzerindeki etkilerinin görülmesini sağlayacak ve bu etkilerin azaltılması için gerekli güçlendirmeleri önerecek bir yazılımlar bütünüdür. Çalışmanın amacı, İstanbul için deprem nedeniyle olası mevcut ve güncellenen riskleri ortaya koymak ve karar vericilere riski ortadan kaldırmak ya da azaltmak için geliştirecekleri zarar azaltma stratejilerinde yardımcı olabilecek güncellenen veri ve yöntemlere göre kendini yenileyebilen bir yazılım geliştirmektir. HAZUS ve MAEviz Amerika’da ulusal düzeyde kullanılan programlardır ve doğal afetlerin insan yaşamına uzun dönem sosyal ve ekonomik etkilerini azaltmada etkin bir rol oynamaktadırlar. Çalışma kapsamında geliştirilen HAZTURK adlı yazılım da bu sistemler gibi depremin toplum üzerindeki fiziksel, sosyal ve ekonomik sonuçlarını tahmin ve analiz eder. Çalışma kapsamında yapılan uygulamada pilot bölge olarak Zeytinburnu ilçesi seçilmiş ve mevcut bina verileri kullanılarak deprem hasar analizi yapılmıştır. Oluşturulan envanterin hasar görebilirlikleri (kırılganlık) saha çalışmaları ile parametrik kırılganlık metodu kullanılarak belirlenmiş ve oluşturulan hasar tahmin yazılımı kullanılarak tüm bina verilerine ait olası deprem sonrası yapısal ve ekonomik kayıplar belirlenmiştir. Anahtar Kelimeler: Deprem hasar tahmini, coğrafi bilgi sistemleri, afet yönetimi, risk yönetimi. After the 1999 earthquakes hit Kocaeli and Düzce, several seismic loss assessment studies were performed for the city of Istanbul; many of them were carried out by the most important academicians in Turkey. However, due to the rapid changes in the exposed inventory of the city, those studies were losing accuracy. This paper presents a seismic loss assessment system that can easily reanalyze earthquake scenarios including updates in the exposed inventory. This software can be used by the government decision makers and disaster management agencies. In the analysis described in this paper, the inventory data for the Zeytinburnu District is updated and visualized by using the rapid visual screening of buildings. Results from a loss assessment for the Zeytinburnu District are presented and compared with the results from previous studies. The loss assessment analysis for this study provide estimates of building damage, retrofit cost and economic loss. The increasing interest in computer-based seismic risk and loss assessment systems imposes new research requirements on the earthquake engineering community. Such systems are being used for the important purposes of disaster response planning and formulating risk reduction policies. Their accuracy and reliability are therefore fundamental to the success of these mitigation measures. The ingredients of seismic loss assessment are hazard, vulnerability or fragility, inventory and integrated visualization (losses). Assessment of the effects of such an earthquake in Istanbul to the buildings, substructures and transportation networks will help excessively in the preparation stage before the disaster. It is obvious that the expected earthquake for the Istanbul will cause inescapable and irreversible consequences for human life and economy of the country. That is why, it should be estimated that which regions will be affected more, which structures will have more damage, and what will be the economic losses after the disaster, to be prepared as good as possible to the expected earthquake. This kind of estimation will help on preparedness for the earthquake, mitigation, early and rapid response stages after the disaster, and recovery phases of the disaster management progress. This estimation methodology is being used on all over the world and giving very convincing results on earthquake cases. The most important component for the loss estimation is a kind of software that can realize all possible earthquake scenarios for the region of interest and provide the results of the affects of those scenarios on the region and offer reinforcements to mitigate the consequences of the disaster. This study based on MAEViz, a multipurpose risk assessment tool recognized by FEMA and supported by NSF in the United States and HAZUS, FEMA's multi-hazard risk assessment tool. This new tool for Turkey comprehensively addresses all aspects of risk assessment and provides "out of the box" analysis. In this study, Zeytinburnu district was chosen as the pilot region and following the development of the system, applied for the Istanbul. The goal of this study is to introduce the current and updated risks because of the earthquake possibility in Istanbul and help the decision makers by developing a living system which, can be updated as the inventory of the region of interest and the methodology for the loss assessment updates itself. By this way it can help the decision makers on eliminating or reducing the risks. In the loss assessment process, the accuracy of the estimation is directly connected to the accuracy and the correctness of the inventory. That is why; the inventory for such an assessment study must be accurate and current. For this study, the damage and losses to be assessed can be listed for the buildings. The first step of the study was to establish an up-to-date and accurate dataset for a region like Istanbul having an outdated and limited data on buildings and perform loss estimation over the established inventory. That is why the Zeytinburnu district was chosen as the pilot study region. The fragilities of this inventory were determined by field surveying and the parametrized fragility method. Loss estimation on the building and utility network data were made using HAZTURK, the developed loss estimation software to determine the post-earthquake structural damage and economic losses. The most important aspect of the software is to enable all possible earthquake scenarios to be analyzed having tools and menus in Turkish. HAZTURK is specifically designed to meet the needs of practitioners and researchers in Turkey with a user-friendly system. Keywords: Earthquake loss assessment, geographic information systems, disaster management, risk management.
The use of geography markup language for the purpose of land registry and cadastral data on the web
Full text linkAçık Kaynaklı CBS Topluluğu (Open GIS Consortium-OGC), Dünya Sanal Doku İşbirliği Topluluğu’nun (World Wide Consortium-W3C) ürettiği Genişletilebilir İşaretleme Dili (Extensible Markup Language-XML) teknolojisine dayalı olarak 29.01.2003 tarihinde Coğrafi İşaretleme Dili (Geography Markup Language-GML) “GML 3.0” sürümünü çıkarmıştır. 15 Temmuz 2005 tarihinde yürürlüğe giren Büyük Ölçekli Harita ve Harita Bilgileri Üretim Yönetmeliğinde Ulusal Veri Değişim Formatı (UVDF) tanımlanmış ve üretilen haritaların, bu formata göre oluşturulacak XML şemasına uygun arşivlenmesi düzenlenmiştir. Tapu ve kadastro verilerinin, OGC standartlarını benimseyen INSPIRE (Infrastructure for Spatial Information in Europe) çalışmalarında bir katman olarak oluşturulması planlanmıştır. Ayrıca, tescile esas güncel ve güncel olmayan tapu ve sayısal kadastro verilerine kolay ulaşabilmesi kullanımda gerekli olmaktadır. Bu nedenlerle tapu ve kadastro verilerinin GML şemalarına dayalı XML ile imlenme ihtiyacı oluşmuştur. Yapılan çalışmada öncelikle, tapu ve kadastro verilerinin imlemesine ait Bütünleşik Modelleme Dili (Unified Modelling Language-UML) sınıf diyagramı oluşturulmuş ve GML kök şemalarını kullanan GML uygulama şeması hazırlanmıştır. GML uygulama şemasına göre XML imlemelerinin yapılışı örnek üzerinde gösterildikten sonra kullanımda olan bir sayısal kadastro paftası ve ilgili tapu verisi imlenmiştir. Sonuçta, hem sayısal kadastro paftaları ile tapu bilgilerine ait güncel ve güncelliğini yitirmiş tescile esas verilerin GML şemalarına uygun imlenmesine hem de UVDF’ye uygun üretilen haritaların sayısal kadastro haritalarıyla ilişkilendirilebilmesi için bir yöntem önerilmiştir. Anahtar Kelimeler: Tapu ve kadastro, açık kaynak teknolojiler, coğrafi işaretleme dili, uygulama şeması, ortak kullanılabilirlik. Geography Markup Language-GML was developed by Open GIS Consortium-OGC. OGC presented GML Version 3.0 on January 29, 2003 based upon the technology of Extensible Markup Language-XML developed by World Wide Web Consortium-W3C. National Data Exchange Format (NDEF) was defined in the Regulation for Production of Large Scale Maps and Mapping Information that came into effect on July 15, 2005, and the maps produced were designed to be archived in line with XML schemas to be formed according to this format. It was planned to constitute a layer for land registry and cadastral data at studies of INSPIRE (Infrastructure for Spatial Information in Europe) that adopted OGC standards. It is of great importance to digitize all current and outdated land registry and cadastral data which are subject to registry, in order for the requesting organizations to make accurate and rapid timely analysis and to access to these data easily. Considering the conduction of time-analysis and digitization of data subject to registry, it became compulsory to mark the land registry and cadastral registry data with XML based on GML schemas. Having the title-deeds and registry data delivered to users through web with this marking, not only the maps produced according to NDEF can be related to digital cadastral maps but also "Land Registry and Cadastre Information Layer" will be formed which is included in action plans within the Project e-transformation Turkey carried out in parallel to Lisbon Strategies Studies updated as i2010 in 2005. There are problems of the use of maps in Turkey together with other maps produced from different producer because they are not digital and do not conform to a common standard. It is necessary for many applications that land registry and cadastral data exist on the maps. Land registry and cadastral data on hand do not conform to a common standard format on digital environment. To prevent economic disadvantage on map production, NDEF was developed and was put in order in the instructions (the Regulation for Production of Large Scale Maps and Mapping Information). Moreover, NDEF was converted to the open source and interoperability technology Extensible Markup Language (XML) in this instructions. In this study, for the time analysis to be made, digital land registry and cadastral sheets were marked according to an application schema prepared using GML schemas developed with XML technology that is among the information technology tools supporting the open source and interoperability. In the application section of the study, two exemplary neighbouring sheets and land registry information that can enlighten all possible applications were prepared in the beginning. According to the sample cadastral sheets (spatial data) and registry data (non-spatial data), Unified Modelling Language-UML class diagrams of the land registry and cadastral data were formed and GML application schema that utilized GML basic schemas was prepared. Sample sheets were marked according to the prepared GML application schemas and queries that could be made according to these markings were shown. Then marking of a digital cadastral sheet in use and related land registry information was conducted, and how the application prepared for the thesis would be used was shown. Additionally, utilizing XML, Extensible Stylesheet Language Transformations-XSLT, XML Schema Definition Language-XSD, Scaleable Vector Graphic-SVG and Hypertext Markup Language-HTML technologies of W3C, presentation of land registry and cadastral data was exemplified on a Web site which was prepared as to be improved according to the developments in these technologies. It is coded by using XSLT, for geometric data in SVG and for non-geometric data in HTML. All documents are linked on a WEB page. To determine the coordinate information of the cadastral parcels was prepared an XML document. This document uses GML schemas and links to European Petroleum Survey Group parameter (EPSG). To determine the coordinate information of SVG documents was prepared Resource Definition Framework (RDF) code. A program was developed for the users using Visual Basic.Net. This program enables preparation of new document, recording the prepared document in the data base and retrieving it and querying the data from the data base. The users can make by means of this program validating and well form control of the documents. Finally, a method was developed to store and transport present land registry and the digital cadastral maps on the Web being used open source and interoperability technologies. Keywords: Land registry and cadastral data, geographic markup language, application schema, open source technology, interoperability
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