WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Conference Object Citation - WoS: 24Effect of pH and Hydration on the Normal and Lateral Interaction Forces Between Alumina Surfaces(2006) Polat, Mehmet; Sato, Kimiyasu; Nagaoka, Takaaki; Watari, KojiNormal and lateral interaction forces between alumina surfaces were measured using Atomic Force Microscopy-Colloid Probe Method at different pH. The normal force curves exhibit a well-defined repulsive barrier and an attractive minimum at acidic pH and the DLVO theory shows excellent agreement with the data. The normal forces are always repulsive at basic pH and the theory fails to represent the measurements. Lateral forces are almost an order of magnitude smaller in the basic solutions. These differences, which have important implications in the study of stability and rheology, are attributed to the hydration of the alumina surface at basic pH. © 2013 Elsevier B.V., All rights reserved.Conference Object Problem of Cracked Infinite Hollow Cylinder With Two Rigid Inclusions(Civil Comp Press, 2000) Artem, HSA; Gecit, MRThis paper is concerned with the fracture of an axisymmetric hollow cylindrical bar containing rigid inclusions. The cylinder is under the action of uniformly distributed axial tension applied at infinity. The hollow cylinder contains a ring-shaped crack at the symmetry plane whose surfaces are free of tractions and two ring-shaped rigid inclusions with negligible thickness symmetrically located on both sides of the crack. Geometry and the loading is symmetric about z-axis. Along the rigid inclusions displacements are constant and continuous whereas stresses have jumps. The inner and the outer surfaces of the cylinder are free of tractions It is assumed that the material of the cylinder is linearly elastic and isotropic. The mixed boundary conditions of the problem lead the analysis to a system of three singular integral equations for crack surface displacement derivative and normal and shear stress jumps on rigid inclusions. These integral equations are solved numerically and the stress intensity factors at the edges of the crack and at the edges of the inclusions are calculated. Results are presented in graphical form.Conference Object Nanoscale Surface Modification of Ultrahigh Molecular Weight Polyethylene (UHMWPE) Samples With the W Plus C Ion Implantation(Materials Research Soc, 2007) Urkac, E. Sokullu; Oztarhan, A.; Tihminlioglu, F.; Kaya, N.; Budak, S.; Chhay, B.; Ila, D.In this work, Ultra High Molecular Weight Poly Ethylene (UHMWPE) samples Were implanted by W + C ions using Metal-Vapour Vacuum Arc (MEVVA) ion implantation system with a fluence of 10(17) ion/cm(2) and extraction voltage of 30 kV. Samples were characterized with Raman Spectra, ATR-FTIR, UV-VIS-NlR Spectrum and RBS. Surface morphology of implanted and unimplanted samples were examined in nanoscale with AFM.Article Citation - WoS: 32Citation - Scopus: 37Teleoperation With Kinematically Redundant Robot Manipulators With Sub-Task Objectives(Cambridge Univ Press, 2009) Nath, Nitendra; Tatlicioglu, Enver; Dawson, Darren M.In this paper, control of nonlinear teleoperator systems where both the master and slave systems are kinematically redundant robot manipulators is addressed. The controller is developed under the assumption that the user and environmental input forces arc unmeasurable. Lyapunov-based stability analysis is used to prove that the proposed controller yields asymptotic tracking results and ensures the coordination of the master and slave systems while satisfying a sub-task objective. Numerical simulation results are presented to illustrate the effectiveness of the proposed controller.Article Citation - WoS: 7Review of Literature for the Concept of Post-Disaster Housing in Turkey(Gazi University, 2008) Baradan, BernaThere have been implementations of post-disaster housing even in historical ages and mentioned in studies concerning a specific period in time in which the disaster occurred in Turkey. With a brief overview of such history of post-disaster housing, the studies were reviewed based on the relationship between approaches and time periods concerning the architectural literature of post-disaster housing in Turkey between 1977 and 2005. There are mainly two types of architectural studies about this concept; observations and analyses about the general policy in Turkey, and case specific studies. These two types of studies can also classified within their writing style as well; descriptive style and analytical style of writing is used for a basis for the comparison of approaches used in the studies. The term ‘architectural literature’ used in this article were used for the works published by the architects and/or studies published in architectural magazines. From this analysis, it could be concluded that the architectural society in Turkey changed its point of view to more humanistic solutions in post-disaster housing after the 1999 Marmara Earthquake.Article Citation - WoS: 37Mechanisms of Cellular Resistance To Imatinib in Human Chronic Myeloid Leukemia Cells(Taylor and Francis Ltd., 2007) Baran, Yusuf; Ural, Ali Uğur; Gündüz, UfukA major advancement in the treatment of chronic myeloid leukemia (CML) has been the development of imatinib, which has shown striking activity in the chronic phase and the accelerated phase, but less so in the blast phase of the disease. Despite high rates of hematologic and cytogenetic responses to therapy, the emergence of resistance to imatinib has been recognized as a major problem in the treatment of patients with CML. Various cellular mechanisms may be involved in the nature of cellular resistance. Increased amount of target, alteration in structure of target proteins, decreased drug uptake and increased detoxification are well-known mechanisms of resistance. On the other hand, in some cases, even if anticancer drugs reach their sites of action, bypassing drug efflux system of the cells, some cells still may survive via the dysregulation of apoptotic signalling. In this study, mechanisms of resistance to imatinib-induced apoptosis in human Meg-01 CML cells were examined. Continuous exposure of cells to step-wise increasing concentrations of imatinib resulted in the selection of 200- and 1000 nM imatinib-resistant sub-lines referred to as Meg-01/IMA-0,2 and Meg-01/1MA-1, respectively. MTT cell proliferation, cell cycle analyses and trypan blue dye exclusion analyses showed that Meg-0l/IMA-1 cells were resistant to imatinib-induced apoptosis as compared to parental sensitive cells. There was an increased expression of BCR/ABL, Bcl-2 and an increase in mitochondrial membrane potential (MMP) detected in resistant cells comparing to parental sensitive cells. There was no mutation detected in imatinib binding site of ABL kinase region. Various diverse mechanisms have been reported for their involvement in the multidrug resistance. In this study, it has been shown that the degree of BCR/ABL expression appears to be directly proportional to the levels of imatinib resistance. In addition, there have been BCR/ABL-independent mechanisms reported for deriving resistance against imatinib. Our results revealed that besides BCR/ABL overexpression, imatinib resistance also depends on the inhibition of apoptosis as a result of up-regulation of anti-apoptotic stimuli and down-regulation of pro-apoptotic stimuli through MMP but does not depend on any mutation on imatinib binding site of ABL kinase.Article Citation - WoS: 5Piranesi Between Classical and Sublime(Orta Doğu Teknik Üniversitesi, 2007) Ek, Fatma İpek; Şengel, DenizOn sekizinci yüzyılda, estetik biliminin olduğu kadar mimarlık tarihinin de doğuşu bağlamında ivme kazanan tartışmalar, mimarlık disiplinini doğal olarak etkilemişti. Estetik tartışmaların temeli mimarilerin tarihsel köken tartışmalarına bağlanıyor ve ‘güzel’ ile ‘yüce’ olmak üzere iki etki üzerine odaklanıyordu: ‘Güzel’i temsil ettiği düşünülen Yunan tarzı, ‘yüce’yle özdeşleştirilen Roma ve Mısır tarzlarının karşısına yerleştirilmekteydi. Giovanni Battista Piranesi (1720-1778) gibi mimar ve düşünürlerin görsel ve yazınsal çalışmalarında söz konusu estetik ve tarihsel savlar takip edilebiliyordu. Piranesi, Roma mimarlık ve uygarlığının kökenini ‘güzel’ Yunan’a dayandıran Winckelmann gibi çağdaşlarının aksine, Roma mimarî estetiğinin ‘yüce’ unsurlar barındırdığını, dolayısıyla Mısır medeniyetinden türediğini savunuyordu. Tüm çizimlerinde antik Roma’nın ‘yüce’ mimarisini resmeden Piranesi, böylece estetik tartışmaların ‘yüce’ cephesinde yerini alıyordu.On sekizinci yüzyılın iki önemli filozofu Immanuel Kant (1724-1804) ile Edmund Burke (1729-1797) estetiğin bileşenleri ‘güzel’ ve ‘yüce’ üzerine çalışmalarıyla tartışmaları hızlandırmıştı. Bu iki kavram on sekizinci yüzyıl felsefe ve tasarım kuramlarını aynı ölçüde etkilemekle birlikte, makale temel olarak Kant ile Burke’ün ‘yüce’ tanımları üzerinden Piranesi’nin görsel ve metinsel çalışmalarının karşılaştırmalı okumasını yapmaktadır. Kant ve Burke’ün ‘yüce’ açıklamalarında küçük ayrılıklar görülmekle birlikte ikisi de temelde aynı şeyi söylemişlerdir. Özellikle Kant’ın Güzellik ve Yücelik Duygusu Üzerine Gözlemler (1764) ve Burke’ün Yücelik ve Güzellik Fikirlerimizin Kaynağı Hakkında Felsefî bir Araştırma (1757) başlıklı çalışmalarındaki ifadeler Piranesi’nin çizimlerinde takip edilebilmektedir. Piranesi, Kant’ın ve Burke’ün anlattığı ‘yüce’yi mimarî çizim diliyle aktarmıştı. Piranesi, on sekizinci yüzyıla egemen olan ‘yüce’ etkiyi Venedikli bir mimarın gözüyle yeniden yorumluyordu.Article Citation - Scopus: 2Mısır, Etrüsk, Roma: Piranesi ve Bir On Sekizinci Yüzyıl Tartışması(Orta Doğu Teknik Üniversitesi, 2008) Ek, Fatma İpek; Şengel, DenizOne crucial debate that resonated in eighteenth-century Europe concerned the origins of European architecture whose effects continue to inform present-day notions of the same. Numerous important eighteenth-century works were produced in the context of emergence of the discipline of architectural history. In this architectural, historical, and archaeological framework, Venetian architect and scholar Giovanni Battista Piranesi (1720- 1778) played an important role by his visual and literary works as well as original approach to history. Piranesi developed a history of architecture that was not based on the East/West division and the separation of continents. In opposition to writers like Winckelmann who rooted the origin of Roman architecture in the Greek, he claimed that Roman architecture derived from the Etruscan which found its roots in Egypt. Discussion of roots depended on the eighteenth century on aesthetical theory interpreting Grecian architecture as ‘beautiful’ and Roman -thus Egyptian- as ‘sublime’. It was in this lively intellectual environment that Piranesi searched the origins of Roman -and thus the whole Europeanarchitecture. His works were, however, misinterpreted as being Orientalist by contemporary scholars following Said.Article Citation - Scopus: 2Kırılan Temsiliyet : Libeskind'de Bellek,tarih ve Mimarlık(Orta Doğu Teknik Üniversitesi, 2009) Maden, Feray; Şengel, DenizMimarisini ‘yokluk,’ ‘yitirilmişlik’ ve ‘bellek’ kavramları üzerinden çizgiler, çarpıtılmış açılar, kesişen geometriler ve boşluklar etrafında kurgulayan Daniel Libeskind, çok disiplinli mimarisi ve radikal yaklaşımları ile kuşkusuz mimarlık kuram ve pratiğini etkileyen ustaların başında gelmektedir (1). Bellek ve tarihin ‘izleri’ üzerinde şekillenen projeleri ve çoğunlukla da müze yapıları ile karşımıza çıkan Libeskind, Rönesanstan bu yana süregelen mimarlıkta temsiliyet sorunsalı, mimarî temsil ve temsilin mimarlığı gibi tartışmalara, sergilediği aykırı mimari ile yeni bir yön kazandırmaktadır. Makalenin hedefi, Libeskind’in proje ve çizimleri üzerinden, mimarın tarihi yorumlaması çerçevesinde temsiliyet sorununu irdelemektir. Bu irdeleme, mimarlık ile tarih arasında kurulan ilişki bakımından birbirinden farklılaşan modern ve postmodern dönemler arasında kendisine yeni bir konum bulan Libeskind’in tarih anlayışını bir kez daha gözden geçirerek yorumlamayı amaçlamaktadır. Yazı ayrıca Libeskind mimarisinin, mimarlığın geleneksel temsillerinden farklılaşarak disiplinler arası bir yaklaşımla diğer alanlarla kurduğu ilişkiyi sorgulamayı da hedeflemektedir.Article Citation - WoS: 13Citation - Scopus: 15Design, Performance, and Calibration of the Cms Hadron-Outer Calorimeter(Springer Verlag, 2008) Karapınar, GülerThe Outer Hadron Calorimeter (HCAL HO) of the CMS detector is designed to measure the energy that is not contained by the barrel (HCAL HB) and electromagnetic (ECAL EB) calorimeters. Due to space limitation the barrel calorimeters do not contain completely the hadronic shower and an outer calorimeter (HO) was designed, constructed and inserted in the muon system of CMS to measure the energy leakage. Testing and calibration of the HO was carried out in a 300 GeV/c test beam that improved the linearity and resolution. HO will provide a net improvement in missing E T measurements at LHC energies. Information from HO will also be used for the muon trigger in CMS. © 2008 Springer-Verlag / Società Italiana di Fisica.