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Review Citation - WoS: 53Citation - Scopus: 60Synthesis and Characterization of Hyperbranched and Air Drying Fatty Acid Based Resins(Elsevier Science Sa, 2006) Bat, E; Gündüz, G; Kisakürek, D; Akhmedov, IMIn this research four hyperbranched resins having fatty acid residues were synthesized. Dipentaerythritol, which was used as the core molecule of the resins, was twice esterified with dimethylol propionic acid. This resin was then esterified with the castor oil fatty acids. The hydroxyl group present in the ricinoleic acid which constitutes almost 87% of the castor oil fatty acids was then reacted with linseed oil fatty acids and benzoic acid. The linseed fatty acids were incorporated into the structure to esterify 0, 15, and 70% of the ricinoleic acid on mole basis. These resins were named as HBR-1, 2, and 3. A fourth resin (e.g. HBR-4) was synthesized by the incorporation of 15% linseed fatty acids + 55% benzoic acid'. The chemical characterization of the resins was achieved by FTIR spectroscopy and the thermal properties were determined by DSC. The physical and the mechanical properties of the resins were determined. The hardness value of the resins was measured as 24, 277 25, and 68 Persoz for HBR-1, 2, 3, and 4, respectively. The viscosity of the resins was measured as 17.3, 9.7, 5.8, and 17.5 Pa(.)s at a shear rate of 200 s(-1). The increase in the amount of the linseed fatty acids increased the hardness, and decreased the viscosity of the resins. All resins showed excellent adhesion, gloss, and flexibility. (c) 2006 Elsevier B.V. All rights reserved.Review Citation - Scopus: 7Yielding of long concentric tubes under radial pressure based on von Mises criterion;(2005) Akiş,T.; Eraslan,A.N.The classical problem of a plain strain tube with free ends, subject to either internal or external pressure is extended to tightly fitted long concentric tubes with axially constrained ends. Making use of von Mises yield criterion, critical values of pressure leading to plastic flow are determined in terms of material properties and tube dimensions.Review Boşluklu Perde Duvar Sistemlerin Serbest Titreşim Periyotlarının Farklı Yöntemlerle Hesaplanması(2003) Akış, Tolga; Coşkun, Safa BozkurtÇok katlı betonarme yapılarda kullanılan boşluklu perde duvarlar, özellikle deprem dayanımları açısından sıkça tercih edilen yapı sistemleridir. Dayanım ve rijitlik bakımından olumlu özelliklere sahip boşluklu perde duvarların, boşluksuz perde duvarlara göre daha sünek davrandığı bilinmektedir. Herhangi bir yapısal sistemin deprem davranışını belirleyen en önemli parametreler sistemin doğal modları ve bu modlara ait periyotlardır. Bu çalışmada, daha önce sınır eleman yöntemi kullanılarak modellenmiş ve serbest titreşim periyottan elde edilmiş bir boşluklu perde duvar sistemin, gerilme elemanlarının kullanıldığı sonlu elemanlar yöntemi ve çubuk elemanların kullanıldığı geniş kolon benzeşimi yöntemi kullanılarak serbest titreşim periyotları bulunmuştur. Analizlerden çıkan sonuçlar karşılaştırılmıştır.Review Religion and Politics - Cultural Perspectives(Brill Academic Publishers, 2006) Stone, Leonard[No Abstract Available]Review Citation - Scopus: 8Anatomy of a failed IMF program: The 1999 program in Turkey(M.E. Sharpe Inc., 2004) Çapoǧlu,G.This paper analyzes the failed IMF program in Turkey that was initiated in December 1999. The 1999 Turkish exchange rate-based stabilization program was presented as an improved version of earlier programs implemented in Latin American countries. The inclusion of an exit strategy was considered as an innovative element of the Turkish program. However, the program crashed fourteen months after its initiation. This paper argues that the Turkish program underestimated the possible negative impact of unfavorable initial conditions, especially conditions of an institutional nature, which turned out to be a fatal mistake. Among the conditions that were ignored by the 1999 program were the absence of an independent and effective regulatory agency in the banking sector and the circumstances under which the Treasury carried out its borrowing.Review Global It Outsourcing: Benefits, Risks and Current Trends(2003) Mishra,A.The growing trends towards information technology (IT) outsourcing is increasing among organizations all over the world. This article reviews the factors, which affects the success in outsourcing, areas of outsourcing, contract-crafting deal, and risk factors involved. It also presents current scenario of global IT outsourcing briefly.Review Ulusal Çıkar Aracı Olarak Uluslararası Politikada Terörizm(2002) Ersoy, HamitUluslararası ilişkilerde terörizmin gündeme oturmasıyla birlikte, terörün uluslararası politikadaki yeri daha da tartışılır hale gelmiştir, işte bu çalışma terörizmin genel kabul gören tanımını ve tasnifini verdikten sonra, bir ülkenin iç ve dış politikasını etkilemek için ülkelerin terörü nasıl kullandıklarını göstermeyi amaçlamaktadır. Bir çıkar aracı olarak uluslararası politikada hem devletlerin hem de çıkar çevrelerinin terörizmi kullanmaktan çekinmediği dikkate alındığında, küresel politikaların yönlendirilmesinde bir araç olarak terörizmin güçlü ülkeler tarafından daha zayıf olan ülkelere karşı niçin ve ne oranda kullandıkları detaylı bir biçimde ele alınmaktadır. Gelişmekte olan ülkelerin iç ve dış politikalarını etkilemede ciddi olarak terörizmin kullanıldığını detaylı bir biçimde gösteren bu araştırma, dış müdahaleciliğin mantığını sorguladıktan sonra, terörizme karşı Türkiye'nin politikasının ne olması gerektiği konusunda öneriler sunmaktadır.Review Central Asia's Second Chance(Brill Academic Publishers, 2006) Stone, Leonard[No Abstract Available]Review Citation - WoS: 5Citation - Scopus: 4A Recovery of Brouncker's Proof for the Quadrature Continued Fraction(Univ Autonoma Barcelona, 2006) Khrushchev, S350 years ago in Spring of 1655 Sir William Brouncker on a request by John Wallis obtained a beautiful continued fraction for 4/pi. Brouncker never published his proof. Many sources on the history of Mathematics claim that this proof was lost forever. In this paper we recover the original proof from Wallis' remarks presented in his "Arithmetica Infinitorum". We show that Brouncker's and Wallis' formulas can be extended to MacLaurin's sinusoidal spirals via related Euler's products. We derive Ramanujan's formula from Euler's formula and, by using it, then show that numerators of convergents of Brouncker's continued fractions coincide tip to a rotation with Wilson's orthogonal polynomials corresponding to the parameters a = 0, b = 1/2, c = d = 1/4.Review Citation - WoS: 55Citation - Scopus: 60The Development of Ring Rolling Technology - Part 2: Investigation of Process Behaviour and Production Equipment(Wiley-blackwell, 2005) Allwood, JM; Tekkaya, AE; Stanistreet, TFThis is the continuation of a thorough survey of work on ring rolling published in the English and German languages up to 2004 [see No. 2/3, p. 111-120]: The methods used to investigate the process are reviewed, separated into experimental and theoretical categories; the insights gained from these investigations are organised according to the challenges identified at the outset; developments in the control and operation of the process are described. Having given a set of ideal targets for the process, the state of current knowledge about ring rolling is assessed in order to predict likely developments: process modelling capability is nearly able to predict rolling behaviour for a complete cycle with sufficient accuracy to allow effective use of models for design of rolling schedules and preforms; analysis of material behaviour is relatively mature for steel rings, but has scope for significant extension for titanium and aluminium alloys and composites; design choices that seek to extend the flexibility of the process have had some exploration, but could be extended.
