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Kablosuz algılayıcı ağlarda (KAA) kısıtlı enerjiyi tedbirli kullanmak için rastgele konumlandırılan algılayıcı düğümler baz alınmaktadır. Yakın mesafedeki algılayıcıları bulup, kümeleme mantığını kullanarak düğümler arası işlevin aşamalı olarak gerçekleştirmesi sağlanmaktadır. Bu tez çalışmasında, geliştirilen yöntemde düşük enerji uyumlu hiyerarşik kümeleme protokolü -Low-Energy Adaptive Clustering Hierarchy- (LEACH) ve K-Mean mimarisini birleştiren küme yapısı gerçekleştirilmiştir. Buna ek olarak eşik değere bağlı ve birbirine yakın mesafedeki düğümleri hedef alarak ikinci düzey bir kümeleme gerçekleştirilmiş ve Enerji Verimli Yakın Düğümleri Kümeleme (EVYDK) - Energy Efficient Close Nodes Clustering – (EECNC) yöntemi geliştirilmiştir. Hedef rastgele dağılımda gerçekleşen ve aynı algı mesafesi kapsamındaki alanda birden fazla algılayıcıdan ziyade tek bir algılayıcının çalışması ve algılama şeklindedir. Böylece algılama esnasında, aynı verilerin tekrarlanarak toplanmasının engellemesinden dolayı, paket hacminin azalması ve algılama için harcanan enerjinin azaltılması yoluyla enerji tasarrufu sağlanmıştır. Randomly oriented sensor nodes are used in wireless sensor networks in order to use limited energy efficiently. To utilize nodes that are close to each other with clustering method, inter-node operations were carried out progressively. In this thesis, Low-Energy Adaptive Clustering Hierarchy (LEACH) and K-mean clustering methods were combined into a new one. In addition, by targeting nodes that are subject to threshold value and close to each other, second level clustering was done and Energy Efficient Close Nodes Clustering (EECNC) method was developed. The use of only one sensor among sensors that have same range which occur in random distribution was aimed. By applying this method, while detecting, having the same data repeatedly, sent packet size was reduced and the energy was saved during detection. 104

The interplay between geophysics and geology is today one of the ma in challenges in reservoir characterization. In this paper we expose the ideia that by careful mathematical formulation and computer graphics tools it is possible to reconstruct 3D geological forms starting with seismic parameters. We reconstruct all the topological components of isosurfaces in subvoxel resolution starting with seismic parameters. Each isosurface component represents the boundary of a geobody. This type of reconstruction helps the modeler to understanding better the seismic information, the geobody spatial characteristics and make quantitative estimations such as reservoir volume.

Bu çalışmada, mobil elektronik imza (me-imza) altyapıları, standartları veme-imzadaki riskler detaylı olarak incelenmiş, güvenli imza oluşturmacihazlarının sağladığı güvenlik ile oluşabilecek muhtemel güvenlik açıklarıaraştırılmıştır. Dünya ülkelerinde uygulanan me-imza altyapıları ileönerilen me-imza modelleri karşılaştırılmıştır. Ülkelerin me-imza altyapılarıözellikle bu konuda atılan adımlar, söz konusu ülkelerin gelecek için meimzakonusunda hedeflerine de bu çalışmada ayrıca yer verilmiştir. Mobilelektronik ortamlara yapılan saldırılar ile bu ortamlarda oluşabilecekaçıklar, oluşan tehditler ayrıca bu tez kapsamında detaylı olarak incelenmişve alınabilecek önlemler sunulmuştur. Sonuç olarak, me-imza vealtyapısının ülkelerin gelişmesine ve işlemleri daha kolay ve güvenliyapılabilmelerine büyük katkılar sağlayacağı, yüksek seviyede bir mobilortam güvenliği için uluslararası standartlara ve ilgili kanunlarınuygulanmasına, bu tez kapsamında sunulan ülke modellerinindeğerlendirilmesi ve EAL4+ seviyesinde güvenlik sağlayan bir SIM kartıkullanılmasına gerek vardır.Anahtar Kelimeler : Açık Anahtar Altyapısı, Mobil Elektronik İmza, Güvenliİmza Oluşturma Cihazları, Modeller, Mobil Ortamlar,Güvenlik Açıkları In this study, the infrastructures, standards and risks on mobile electronicsignature (me-sign) have been examined in detail. Security provided by thesecure signature creation devices and possible security vulnerabilities havebeen researched. The me-sign infrastructures, and recommended me-signmodels, have been compared. The me-sign infrastructures of countries,especially the steps that are taken on this issue, the targets of the countriesfor me-sign have also been considered. The attacks to me-sign and mobileelectronic medias and the vulnerabilities and the risks encountered havebeen presented. As a result, me-sign and its infrastructure would bebeneficial for the countries protecting information and electronic media.This will contribute to make the procedures easier and safer, allow forimplementation of the laws related to the international standards for thehigh-level security of the mobile media, and will be beneficial to use a SIMcard at EAL4+ level within the country models, presents under this thesis.Key Words : PKI, me-sign, SSCD, Models, Mobile Platform, SecurityVulnerability 135

Kernel based methods and support vector machines are recog nized today as important methods in areas such as artificial intelligence and bioinformatics, among others. Increasingly in the last years applications to geophysics is becoming widespread, emphasis made to the oil industry. In this paper we propose a new method to distinguish between reservoir and non reservoir characteristics in a seismic sample. Volumetric multiatribute seismic and well data are used in the training process. Introducao

The understanding of large data clustering is a relevant prob lem in several areas of science and engineering. Seismic signal are in general represented by large data sets. For petroleum geophysicists the choice of areas of interest is a demanding task. In this paper we introduce data mining visualizationtechniques, stellar coordinates and transfer functions, which easy the task of dealing visually with data clustering in an interactive and intuitive way allowing the user to make meaningful choices of 3D regions of interest to work with. Introducao A exploracao e analise de dad os multiatributos e um importante assunto em diferentes areas como simulacao de fluidos, imagens medicas e geofisicas. Pesquisadores da area de visualizacao da informacao desenvolveram inumeras tecnicas para explorar e analisar interativamente dados multivariados. Milhoes de amostras conduzem a uma dificuldade de selecao de poucas amostras que conduza a um interesse economico ou geocientifico, num determinado bancos de dados, que geralmente sao muito grandes e complexos. Uma solucao efetiva e alcancada ao se colocar o conhecimento humano e a interacao nesse processo de exploracao.

Summary The integration of seismic data into the reservoir characterization process is very important in cases where the amount of well information is sparse. This is the case for most of the Campos Basin oil fields as well as for the field object of this study. Due to the large well spacing in this field, the use of seismic derived attributes to constrain the reservoir modeling is of paramount importance. For this case, the seismic amplitude, the most common seismic attribute used for reservoir characterization in Campos Basin, shows very weak correlation with the reservoir properties mainly due to strong impedance variations of the overlain beds. The alternative attribute chosen was the acoustic impedance derived from a post-stack seismic inversion. Such attribute showed better correlation with the reservoir properties of interest and it was then incorporated to the reservoir characterization process via geostatistical procedures. Stochastic simulation algorithms were used to generate facies and porosity models: the acoustic impedance was used as a soft constraint for the facies modeling and the facies distribution conditioned the porosity realizations. Based on the geological knowledge of the reservoir, some porosity models were selected to be the basis of the flow simulation model.

One of the greatest difficulties found in reservoir geophysics is the lack of new seismic acquisition and pre-stack migration in 3D’s acquired in the past. A way to improve the data image is to migrate the 3D data in one step in the PROMAX processing package. The response of it was excellent to get a good image from faults, making its traces better focused in the seismic sections, and so helping the mapping. This fact is very important in the location of development wells. The response was very satisfactory in positioning pinch-outs features of channels and/or lobes. It will be shown how this migration helped to solve some troubles in a Campos Basin oil field, where we have got a good amplitude response but only 10 meters of reservoir, or we could not define sand bodies limits.

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