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Articles 1 - 30 of 319
Full-Text Articles in Physical Sciences and Mathematics
Neotectonic Characteristics Of The İnönü-Eskişehir Fault System In The Kaymaz (Eskişehir) Region: Influence On The Development Of The Mahmudiye-Çifteler-Emirdağ Basin, Azad Selçuk, Yaşar Ergün Gökten
Neotectonic Characteristics Of The İnönü-Eskişehir Fault System In The Kaymaz (Eskişehir) Region: Influence On The Development Of The Mahmudiye-Çifteler-Emirdağ Basin, Azad Selçuk, Yaşar Ergün Gökten
Turkish Journal of Earth Sciences
The İnönü-Eskişehir Fault System (İEFS) is a NW- to WNW-trending zone of active deformation about 15-25 km wide, 400 km long and characterized predominatly by strike-slip faulting. In this study, the Yörükkaracaören (SE of Eskişehir)-Sivrihisar section of the İEFS was investigated. The system consists of three fault zones, namely the Alpu Fault Zone (AFZ), the Eskişehir Fault Zone (EFZ) and the Orhaniye Fault Zone (OFZ) in the study area. The EFZ is made up mostly of N30°W-trending right-lateral strike-slip fault segments with normal components. However, the AFZ and OFZ are composed of E-W-trending normal and NE- to NW-trending strike-slip fault …
Approximate Groups Iii: The Unitary Case, Emmanuel Breuillard, Ben Green
Approximate Groups Iii: The Unitary Case, Emmanuel Breuillard, Ben Green
Turkish Journal of Mathematics
By adapting the classical proof of Jordan's theorem on finite subgroups of linear groups, we show that every approximate subgroup of the unitary group U_n(C) is almost abelian.
Groupoids, Imaginaries And Internal Covers, Ehud Hrushovski
Groupoids, Imaginaries And Internal Covers, Ehud Hrushovski
Turkish Journal of Mathematics
Let T be a first-order theory. A correspondence is established between internal covers of models of T and definable groupoids within T. We also consider amalgamations of independent diagrams of algebraically closed substructures, and find strong relation between covers, uniqueness for 3-amalgamation, existence of 4-amalgamation, imaginaries of T^\si, and definable groupoids. As a corollary, we describe the imaginary elements of families of finite-dimensional vector spaces over pseudo-finite fields.
On \Alpha-Skew Mccoy Modules, Jian Cui, Jianlong Chen
On \Alpha-Skew Mccoy Modules, Jian Cui, Jianlong Chen
Turkish Journal of Mathematics
Let \alpha be a ring endomorphism. Extending the notions of McCoy modules and \alpha-skew McCoy rings, we introduce the notion of \alpha-skew McCoy modules, which can also be regarded as a generalization of \alpha-skew Armendariz modules. A number of illustrative examples are given. Various properties of these modules are developed, and equivalent conditions for \alpha-skew McCoy modules are established. Furthermore, we study the relationship between a module and its polynomial module.
On Some New Inequalities For Convex Functions, Mevlüt Tunç
On Some New Inequalities For Convex Functions, Mevlüt Tunç
Turkish Journal of Mathematics
In the present paper we establish some new integral inequalities analogous to the well known Hadamard's inequality by using a fairly elementary analysis.
Note On Hilbert-Type Inequalities, Predrag Vukovic
Note On Hilbert-Type Inequalities, Predrag Vukovic
Turkish Journal of Mathematics
The main objective of this paper is to prove Hilbert-type and Hardy-Hilbert-type inequalities with a general homogeneous kernel, thus generalizing a result obtained in [Namita Das and Srinibas Sahoo, A generalization of multiple Hardy-Hilbert's integral inequality, Journal of Mathematical Inequalities, 3(1), (2009), 139--154].
An Oscillation Theorem For Second-Order Nonlinear Differential Equations Of Euler Type, Asadollah Aghajani, Vahid Roomi
An Oscillation Theorem For Second-Order Nonlinear Differential Equations Of Euler Type, Asadollah Aghajani, Vahid Roomi
Turkish Journal of Mathematics
We consider the nonlinear equation t^2x'' + g(x) = 0, where g(x) satisfies xg(x) > 0 for x \ne 0, but is not assumed to be sublinear or superlinear. We study the problem whether all nontrivial solutions of the equation are oscillatory in some critical cases.
A Generalization Of Banach's Contraction Principle For Some Non-Obviously Contractive Operators In A Cone Metric Space, Yingxin Guo
Turkish Journal of Mathematics
This paper investigates the fixed points for self-maps of a closed set in a space of abstract continuous functions. Our main results essentially extend and generalize some fixed point theorems in cone metric spaces. An application to differential equations is given.
Marcinkiewicz-Fejer Means Of Double Conjugate Walsh-Kaczmarz-Fourier Series And Hardy Spaces, Ushangi Goginava, Karoly Nagy
Marcinkiewicz-Fejer Means Of Double Conjugate Walsh-Kaczmarz-Fourier Series And Hardy Spaces, Ushangi Goginava, Karoly Nagy
Turkish Journal of Mathematics
In the present paper we prove that for any 0 < p \leq 2/3 there exists a martingale f in H_p such that the Marcinkiewicz-Fejér means of double conjugate Walsh-Kaczmarz-Fourier series of the martingale f is not uniformly bounded in the space L_p.
Extended Cross Product In A 3-Dimensional Almost Contact Metric Manifold With Applications To Curve Theory, Çeti̇n Camci
Extended Cross Product In A 3-Dimensional Almost Contact Metric Manifold With Applications To Curve Theory, Çeti̇n Camci
Turkish Journal of Mathematics
In this work, we define a new cross product in 3-dimensional almost contact metric manifold and we study the theory of curves using this new cross product in this manifold. Besides, in the works of Baikousis, Blair [1] and Cho et al. [4], we observe that some theorems are incomplete and excessively generalized are thus their alternative proofs presented.
Warped Product Submanifolds Of A Kenmotsu Manifold, Siraj Uddin, Viqar Azam Khan, Khalid Ali Khan
Warped Product Submanifolds Of A Kenmotsu Manifold, Siraj Uddin, Viqar Azam Khan, Khalid Ali Khan
Turkish Journal of Mathematics
In the present paper, we study warped product semi-slant submanifolds of a Kenmotsu manifold. We obtain some results on the existence of such type warped product submanifolds of a Kenmotsu manifold with an example.
Geodesicity And Isoclinity Properties For The Tangent Bundle Of The Heisenberg Manifold With Sasaki Metric, Simona Luiza Druta, Paola Piu
Geodesicity And Isoclinity Properties For The Tangent Bundle Of The Heisenberg Manifold With Sasaki Metric, Simona Luiza Druta, Paola Piu
Turkish Journal of Mathematics
We prove that the horizontal and vertical distributions of the tangent bundle with the Sasaki metric are isocline, the distributions given by the kernels of the horizontal and vertical lifts of the contact form \omega on the Heisenberg manifold (H_3,g) to (TH_3,g^S) are not totally geodesic, and the distributions F^H=L(E_1^H,E_2^H) and F^V=L(E_1^V,E_2^V) are totally geodesic, but they are not isocline. We obtain that the horizontal and natural lifts of the curves from the Heisenberg manifold (H_3,g), are geodesics on the tangent bundle endowed with the Sasaki metric (TH_3,g^s), if and only if the curves considered on the base manifold are …
Ion Probe U-Pb Dating Of The Central Sakarya Basement: A Peri-Gondwana Terrane Intruded By Late Lower Carboniferous Subduction/Collision-Related Granitic Rocks, Petek Ayda Ustaömer, Ti̇mur Ustaömer, Alastair Robertson
Ion Probe U-Pb Dating Of The Central Sakarya Basement: A Peri-Gondwana Terrane Intruded By Late Lower Carboniferous Subduction/Collision-Related Granitic Rocks, Petek Ayda Ustaömer, Ti̇mur Ustaömer, Alastair Robertson
Turkish Journal of Earth Sciences
Ion probe dating is used to determine the relative ages of amphibolite-facies meta-clastic sedimentary rocks and crosscutting granitoid rocks within an important 'basement' outcrop in northwestern Turkey. U-Pb ages of 89 detrital zircon grains separated from sillimanite-garnet micaschist from the Central Sakarya basement terrane range from 551 Ma (Ediacaran) to 2738 Ma (Neoarchean). Eighty five percent of the ages are 90-110% concordant. Zircon populations cluster at ~550-750 Ma (28 grains), ~950-1050 Ma (27 grains) and ~2000 Ma (5 grains), with smaller groupings at ~800 Ma and ~1850 Ma. The first, prominent, population (late Neoproterozoic) reflects derivation from a source area …
Petrogenesis Of Late Cretaceous Adakitic Magmatism In The İstanbul Zone (Çavuşbaşı Granodiorite, Nw Turkey), Sabah Yilmaz Şahi̇n, Namik Aysal, Yildirim Güngör
Petrogenesis Of Late Cretaceous Adakitic Magmatism In The İstanbul Zone (Çavuşbaşı Granodiorite, Nw Turkey), Sabah Yilmaz Şahi̇n, Namik Aysal, Yildirim Güngör
Turkish Journal of Earth Sciences
The Çavuşbaşı granodiorite intrudes Ordovician sedimentary rocks in the western part of the İstanbul Zone (NW Turkey). The intrusion is made up mainly of granodiorite, and subordinate tonalite and quartz diorite, and has a granular texture and some special mixing textures such as antirapakivi, blade-shaped biotite, acicular apatite, spongy cellular dissolution/melting plagioclase textures. The main mafic minerals are hornblende and biotite. U-Pb in-situ dating of zircons from two samples via SHRIMP yielded weighted age values of ~68 Ma, suggesting emplacement during the Late Cretaceous. Geochemically the Çavuşbaşı granodiorite resembles adakites with high Sr/Y and La/Yb ratios, low Y and HREE …
Testing Alternative Tectono-Stratigraphic Interpretations Of The Late Palaeozoic−Early Mesozoic Karakaya Complex In Nw Turkey: Support For An Accretionary Origin Related To Northward Subduction Of Palaeotethys, Alastair Robertson, Ti̇mur Ustaömer
Testing Alternative Tectono-Stratigraphic Interpretations Of The Late Palaeozoic−Early Mesozoic Karakaya Complex In Nw Turkey: Support For An Accretionary Origin Related To Northward Subduction Of Palaeotethys, Alastair Robertson, Ti̇mur Ustaömer
Turkish Journal of Earth Sciences
Lower Carboniferous-Upper Triassic rocks of the Karakaya Complex exposed E-W across Turkey are critical to reconstructions of Palaeotethys in the Eastern Mediterranean region. Despite decades of research, the origin and emplacement of the Karakaya Complex remains controversial because it is mapped either as an overall stratigraphic succession of sedimentary olistostromes or as a stack of thrust sheets and mélange. Tectonic models include a continental rift, a back-arc rift, a marginal oceanic basin, and an accretionary prism formed by subduction of a wide ocean. Subduction is seen as either northwards or southwards. To test the alternatives, the various litho-tectonic units and …
The Palu-Uluova Strike-Slip Basin In The East Anatolian Fault System, Turkey: Its Transition From The Palaeotectonic To Neotectonic Stage, Serap Çolak, Ercan Aksoy, Ali̇ Koçyi̇ği̇t, Murat İnceöz
The Palu-Uluova Strike-Slip Basin In The East Anatolian Fault System, Turkey: Its Transition From The Palaeotectonic To Neotectonic Stage, Serap Çolak, Ercan Aksoy, Ali̇ Koçyi̇ği̇t, Murat İnceöz
Turkish Journal of Earth Sciences
The East Anatolian fault system (EAFS) is the 80-km-wide, 700-km-long, NE-trending sinistral strike-slip fault system forming a seismically very active intracontinental transfom fault boundary. It is located between Karlıova County in the northeast and Karataş-Samandağ counties in the southwest, and forms the southeastern boundary of the Anatolian platelet. The Palu-Uluova basin is one of several strike-slip basins located along the EAFS. It is surrounded by several push-ups such as the Karaömerdağı, Mastardağı and Askerdağı push-ups caused by the complexities peculiar to strike-slip faulting. The Palu-Uluova basin consists of three sub-sections: two are NE-trending strike-slip sub-basins, the Uluova and the Palu-Kumyazı …
Early Oligocene Continental Climate Of The Palaeogene Basin (Hungary And Slovenia) And The Surrounding Area, Boglarka Erdei, Torsten Utescher, Lilla Hably, Julia Tamás, Anita Roth-Nebelsick, Michaela Grein
Early Oligocene Continental Climate Of The Palaeogene Basin (Hungary And Slovenia) And The Surrounding Area, Boglarka Erdei, Torsten Utescher, Lilla Hably, Julia Tamás, Anita Roth-Nebelsick, Michaela Grein
Turkish Journal of Earth Sciences
This paper concentrates on the Early Oligocene palaeoclimate of the southern part of Eastern and Central Europe and gives a detailed climatological analysis, combined with leaf-morphological studies and modelling of the palaeoatmospheric CO_2 level using stomatal and \delta^1^3C data. Climate data are calculated using the Coexistence Approach for Kiscellian floras of the Palaeogene Basin (Hungary and Slovenia) and coeval assemblages from Central and Southeastern Europe. Potential microclimatic or habitat variations are considered using morphometric analysis of fossil leaves from Hungarian, Slovenian and Italian floras. Reconstruction of CO_2 is performed by applying a recently introduced mechanistic model. Results of climate analysis …
Palaeoclimate Estimates For Selected Leaf Floras From The Late Pliocene (Reuverian) Of Central Europe Based On Different Palaeobotanical Techniques, Christine Thiel, Stefan Klotz, Dieter Uhl
Palaeoclimate Estimates For Selected Leaf Floras From The Late Pliocene (Reuverian) Of Central Europe Based On Different Palaeobotanical Techniques, Christine Thiel, Stefan Klotz, Dieter Uhl
Turkish Journal of Earth Sciences
To provide quantitative palaeoclimate estimates based on different palaeobotanical techniques for three contemporaneous Pliocene leaf floras, we applied the Coexistence Approach (CoA), leaf margin analysis (LMA), the Climate Leaf Analysis Multivariate Program (CLAMP) and the European Leaf Physiognomic Approach (ELPA). Furthermore, we compared recently published estimates from an additional locality with our data. The leaf physiognomic techniques yield lower mean annual temperatures than the CoA, which is most likely caused by taphonomic biases. Due to these potential biases we are in favour of the CoA as the most reliable method, and its palaeotemperature estimates show similar temperatures for all localities. …
Carbon Isotope And Stomatal Data Of Late Pliocene Betulaceae Leaves From Sw China: Implications For Palaeoatmospheric Co2-Levels, Bainian Sun, Suting Ding, Jingyu Wu, Chong Dong, Sanping Xie, Zhicheng Lin
Carbon Isotope And Stomatal Data Of Late Pliocene Betulaceae Leaves From Sw China: Implications For Palaeoatmospheric Co2-Levels, Bainian Sun, Suting Ding, Jingyu Wu, Chong Dong, Sanping Xie, Zhicheng Lin
Turkish Journal of Earth Sciences
The cuticular \delta^1^3C values and stomatal parameters (stomatal density and stomatal index: SD and SI) of two Betulaceae species, Betula mioluminifera Hu et Chaney and Carpinus miofangiana Nathorst, from a suite of superposed horizons in West Yunnan, southwestern China, were measured in order to recover Late Pliocene CO2 levels. Correlations are given for \delta^1^3C, SD, epidermal cell density (ECD), and SI. \delta^1^3C reveals a positive trend with the SD and SI in the two species, and such a positive correlation can also be observed between the \delta^1^3C and ECD in C. miofangiana. However, \delta^1^3C has a slightly negative correlation with …
Palaeoclimate Evolution In Siberia And The Russian Far East From The Oligocene To Pliocene – Evidence From Fruit And Seed Floras, Svetlana Popova, Torsten Utescher, Dmitry Gromyko, Angela Bruch, Volker Mosbrugger
Palaeoclimate Evolution In Siberia And The Russian Far East From The Oligocene To Pliocene – Evidence From Fruit And Seed Floras, Svetlana Popova, Torsten Utescher, Dmitry Gromyko, Angela Bruch, Volker Mosbrugger
Turkish Journal of Earth Sciences
The Cenozoic continental deposits of Western Siberia, Eastern Siberia and the Russian Far East are best described on the basis of carpological records. The palaeoclimate evolution has been reconstructed quantitatively (Coexistence Approach) providing inferred data on temperature, precipitation and the mean annual range of these parameters. Climate curves document the transition from very warm and humid conditions in the Late Oligocene via the Middle Miocene Climatic Optimum to a cool temperate climate during the Pliocene. Compared with other time intervals the Miocene climate is the most comprehensively reconstructed. For the Middle Miocene the Siberian and Far Eastern data are combined …
A Neural-Based Electromagnetic Inverse Scattering Approach To The Detection Of A Conducting Cylinder Coated With A Dielectric Material, Senem Makal, Ahmet Kizilay
A Neural-Based Electromagnetic Inverse Scattering Approach To The Detection Of A Conducting Cylinder Coated With A Dielectric Material, Senem Makal, Ahmet Kizilay
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, a radial basis function neural network approach is applied for the estimation of the localization and the radius of a conducting cylinder with a circular cross-section coated with a dielectric material. A set of features, the radar cross-section (RCS) values, are derived from scattered fields, which are calculated using the surface equivalence principle and the method of moment. RCS values are obtained using 10 different scattering angles that are fed into the network. The outputs of the network are the location (x_0, y_0) and the radius (r_p) of the conducting cylinder. This is an application of the …
Palaeoflora And Climate Of Lignite-Bearing Lower−Middle Miocene Sediments In The Seyitömer And Tunçbilek Sub-Basins, Kütahya Province, Northwest Turkey, Mehmet Serkan Akki̇raz, Funda Akgün, Torsten Utescher, Volker Wilde, Angela Anneliese Bruch, Volker Mosbrugger, Sari̇ye Duygu Üçbaş
Palaeoflora And Climate Of Lignite-Bearing Lower−Middle Miocene Sediments In The Seyitömer And Tunçbilek Sub-Basins, Kütahya Province, Northwest Turkey, Mehmet Serkan Akki̇raz, Funda Akgün, Torsten Utescher, Volker Wilde, Angela Anneliese Bruch, Volker Mosbrugger, Sari̇ye Duygu Üçbaş
Turkish Journal of Earth Sciences
Lower-Middle Miocene successions from Kütahya province (Seyitömer and Tunçbilek sub-basins) were analyzed to reconstruct the palaeoclimate and vegetation of the period. A rich coniferous forest formed the dominant components among sporomorphs and consisted mainly of undeterminable Pinaceae, Pinus haploxylon type, Pinus diploxylon type, Picea, Cedrus, Cathaya, Keteleeria and Podocarpus. Pollen data also indicate the presence of some fern taxa (Osmunda, Polypodiaceae, Schizeaceae) Selaginella and Lycopodium. Cupressaceae frequently occur in all samples from both sub-basins, and form part of the mixed forest assemblage. Two woody plants Castanea-Castanopsis and evergreen Quercus predominate in the assemblages as well. The reconstruction of palaeoclimate is …
Palaeoclimatic Estimates For The Late Pliocene Based On Leaf Physiognomy From Western Yunnan, China, Sanping Xie, Sun Bainian, Jinyu Wu, Zhicheng Lin, Defei Yan, Liang Xiao
Palaeoclimatic Estimates For The Late Pliocene Based On Leaf Physiognomy From Western Yunnan, China, Sanping Xie, Sun Bainian, Jinyu Wu, Zhicheng Lin, Defei Yan, Liang Xiao
Turkish Journal of Earth Sciences
Based on leaf physiognomy of the Late Pliocene Tuantian megaflora from the Mangbang Formation of Tengchong County in western Yunnan, a quantitative reconstruction of palaeoclimate was performed with Leaf Margin Analysis (LMA) methodology and the Climate-Leaf Analysis Multivariate Program (CLAMP). The latter produced the following parameters: mean annual temperature (MAT) from 17.2 to 17.7°C; warmest month mean temperature (WMMT) from 25 to 25.5°C; coldest month mean temperature (CMMT) from 9.5 to 10.8°C; length of growing season (GRS) from 9.5 to 9.7 months; growing season precipitation (GSP) from 1834.3 to 1901.2 mm; mean monthly growing season precipitation (MMGSP) from 222.4 to …
Silurian Graptolite, Conodont And Cryptospore Biostratigraphy Of The Gülüç Section In Ereğli, Zonguldak Terrane, Nw Anatolia, Turkey, Valeri Sachanski, Mehmet Cemal Göncüoğlu, Iskra Lakova, Ilina Boncheva, Gülnur Saydam-Demi̇ray
Silurian Graptolite, Conodont And Cryptospore Biostratigraphy Of The Gülüç Section In Ereğli, Zonguldak Terrane, Nw Anatolia, Turkey, Valeri Sachanski, Mehmet Cemal Göncüoğlu, Iskra Lakova, Ilina Boncheva, Gülnur Saydam-Demi̇ray
Turkish Journal of Earth Sciences
The studied Gülüç section of the Silurian Fındıklı Formation is situated on the western bank of Gülüç Creek in Ereğli, NW Anatolia, Turkey, in the eastern part of the Zonguldak Terrane. The Gülüç section consists of 3 sedimentary packages: greenish grey limy siltstones, 5-7 m thick (1), overlain by an irregular alternation of black shales and clayey limestones, about 15 m thick (2), and a 6-7 m thick succession of mainly siltstones and sandy limestones (3). A combined biostratigraphy based upon graptolites, cryptospores and conodonts indicates that Package 1 is of Llandovery (Rhuddanian, Aeronian and/or early Telychian) age, Package 2 …
The Unaz Formation: A Key Unit In The Western Black Sea Region, N Turkey, Okan Tüysüz, İsmai̇l Ömer Yilmaz, Lilian Svabenicka, Sabri̇ Ki̇ri̇ci̇
The Unaz Formation: A Key Unit In The Western Black Sea Region, N Turkey, Okan Tüysüz, İsmai̇l Ömer Yilmaz, Lilian Svabenicka, Sabri̇ Ki̇ri̇ci̇
Turkish Journal of Earth Sciences
The Pontide magmatic belt in the Western Pontides, which developed in response to the northward subduction of the northern branches of the Tethys Ocean, consists of two different volcanic successions separated by an Upper Santonian pelagic limestone unit, the Unaz Formation. The first period of volcanism and associated sedimentation started during the Middle Turonian and lasted until the Early Santonian under the control of an extensional tectonic regime, which created horst-graben topography along the southern Black Sea region. The lower volcanic succession, the Dereköy Formation, was deposited mainly within these grabens. This extensional period probably represents the rifting of magmatic …
New Change Impact Factor Estimation In Software Development, Murat Kahraman Güngör, Ersi̇n Elbaşi, James Walter Fawcett
New Change Impact Factor Estimation In Software Development, Murat Kahraman Güngör, Ersi̇n Elbaşi, James Walter Fawcett
Turkish Journal of Electrical Engineering and Computer Sciences
Change in software is always an essential part of software development and maintenance. Estimating a proposed change's effect on the later phases of the development helps project managers and developers with decision-making and predicting future progress. During development, on some occasions, speedy solutions are necessary to meet project schedules. Such quick changes may lead to major quality flaws in the long term, even though they solve local problems in the short term. Controlled management of change is achieved by being able to estimate the impact of changes. In this paper, we propose a new change impact factor estimation and present …
Optimization Of Pilot Tones Using Differential Evolution Algorithm In Mimo-Ofdm Systems, Muhammet Nuri̇ Seyman, Necmi̇ Taşpinar
Optimization Of Pilot Tones Using Differential Evolution Algorithm In Mimo-Ofdm Systems, Muhammet Nuri̇ Seyman, Necmi̇ Taşpinar
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we propose a differential evolution (DE) algorithm for optimizing the placement and power of the pilot tones that are utilized by a least square (LS) algorithm for channel estimation in multiple-input and multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. Computer simulations demonstrated that the performance of the LS algorithm was increased by optimizing the pilot tones with the DE algorithm instead of locating them orthogonally. We used the upper bound of the mean square error (MSE) as a fitness function of the DE algorithm for optimization tasks. With the use of an upper bound, it is not necessary …
An Improved Fastslam Framework Using Soft Computing, Ramazan Havangi, Mohammad Ali Nekoui, Mohammad Teshnehlab
An Improved Fastslam Framework Using Soft Computing, Ramazan Havangi, Mohammad Ali Nekoui, Mohammad Teshnehlab
Turkish Journal of Electrical Engineering and Computer Sciences
FastSLAM is a framework for simultaneous localization and mapping (SLAM) using a Rao-Blackwellized particle filter. However, FastSLAM degenerates over time. This degeneracy is due to the fact that a particle set estimating the pose of the robot loses its diversity. One of the main reasons for losing particle diversity in FastSLAM is sample impoverishment. In this case, most of the particle weights are insignificant. Another problem of FastSLAM relates to the design of an extended Kalman filter (EKF) for the landmark position's estimation. The performance of the EKF and the quality of the estimation depend heavily on correct a priori …
Action-Reaction Based Parameters Identification And States Estimation Of Flexible Systems, Islam Shoukry, Emrah Deni̇z Kunt, Asif Sabanovic
Action-Reaction Based Parameters Identification And States Estimation Of Flexible Systems, Islam Shoukry, Emrah Deni̇z Kunt, Asif Sabanovic
Turkish Journal of Electrical Engineering and Computer Sciences
This work attempts to identify and estimate flexible system's parameters and states by a simple utilization of the Action-Reaction law of dynamical systems. Attached actuator to a dynamical system or environmental interaction imposes an action that is instantaneously followed by a dynamical system reaction. The dynamical system's reaction carries full information about the dynamical system including system parameters, dynamics and externally applied forces that arise due to system interaction with the environment. This in turn implies that the dynamical system's reaction can be considered as a natural feedback as it carries full coupled information about the dynamical system. The idea …
Ttradeoff Tables For Compression Functions: How To Invert Hash Values Radeoff Tables For Compression Functions: How To Invert Hash Values, Orhun Kara, Adem Atalay
Ttradeoff Tables For Compression Functions: How To Invert Hash Values Radeoff Tables For Compression Functions: How To Invert Hash Values, Orhun Kara, Adem Atalay
Turkish Journal of Electrical Engineering and Computer Sciences
Hash functions are one of the ubiquitous cryptographic functions used widely for various applications such as digital signatures, data integrity, authentication protocols, MAC algorithms, RNGs, etc. Hash functions are supposed to be one-way, i.e., preimage resistant. One interesting property of hash functions is that they process arbitrary-length messages into fixed-length outputs. In general, this can be achieved mostly by applying compression functions onto the message blocks of fixed length, recursively. The length of the message is incorporated as padding in the last block prior to the hash, a procedure called the Merkle-Damgard strengthening. In this paper, we introduce a new …