A Note on Doubly Warped Product Contact CR-Submanifolds in trans-Sasakian Manifolds

Warped product CR-submanifolds in Kaehlerian manifolds were intensively studied only since 2001 after the impulse given by B.Y. Chen. Immediately after, another line of research, similar to that concerning Sasakian geometry as the odd dimensional version of Kaehlerian geometry, was developed, namely warped product contact CR-submanifolds in Sasakian manifolds. In this note we proved that there exists no proper doubly warped product contact CR-submanifolds in trans-Sasakian manifolds.Comment: 5 Latex page

Üniversite Mezunlarının İstihdam Sorunları

İnsan gereksinimleri hıza çeşitlenmekte ve buna bağlı olarak bir yandan çok çeşitli üretim kolları oluşmakta, diğer yandan da üretim kapasitesi hızla genişlemektedir. Oysa yeryüzünde istihdam sorununu çözen ülkeye de rastlanmamaktadır. Elbette bunu engelleyen süreçlerden de söz etmek olasıdır. Ancak, toplumdaki eğitilmiş bireylerin en üst dilimlerinden birini oluşturan üniversite mezunlarının istihdam sorunları bile önemli boyutlarda olmayı sürdürmektedir

CYCLIC SEDIMENTATION ACROSS THE PERMIAN – TRIASSIC BOUNDARY (CENTRAL TAURIDES, TURKEY)

The best preserved Permian-Triassic boundary beds in Turkey are found in the Hadim region of the central Taurides. The succession is exposed in one of the allochthonous units of the Tauride Belt, the Aladag Unit, whose stratigraphy includes beds ranging from the Devonian to the Cretaceous systems. In the Aladag Unit, the Permian-Triassic boundary beds are entirely composed of carbonates. The Permian portion of these beds belongs to the Paradagmarita Zone, whereas the lowermost Triassic contains the Lower Griesbachian marker Rectocornuspira kalhori. The uppermost Permian carbonates, composed of meter-scale upward shallowing subtidal cycles, are characterized by oolitic limestones of regressive character at the top and are overlain sharply by Lower Triassic stromatolites. Cyclic Upper Permian carbonates are interpreted as highstand sytems tract deposits of the last third-order sequence of the Permian System. The Permian-Triassic boundary is an unconformity corresponding to both erosional and non-depositional hiatuses. The gap at the Permian-Triassic boundary partially corresponds to the shelf-margin systems tract and partly to the transgressive systems tract of the overlying third-order sequence. Stromatolites are interpreted as transgressive systems tract deposits. Special issueInternational Conference on Paleozoic Foraminifera, Paleoforams 2001Edited by Demir Altiner (Guest Editor

The relationship between the upper level planning system and disaster management

Bu çalışmada, planlama sistemi ve afet yönetimi ilişkileri sistemci bir yaklaşımla incelenmiştir. Planlama sisteminin alt sistemlerinden birisi olan üst düzey planlama sisteminde, afet yönetimi kapsamında yaşanan sorunlar ve sistemin sağlıklı çalışmadığı noktalar neden-sonuç ilişkisi içinde değerlendirilmiştir. Afet yönetiminin afet öncesi çalışmaları kapsamındaki ana kaynağı, üst düzey planlar ile başlayan ve yerel ölçekteki planlarla uygulama bulan “Planlama Sistemi”nin doğru çalıştırılması ve yerleşmelerin yer seçiminin sağlıklı bir biçimde yapılmasıdır. Afet etkilerine duyarlı olarak hazırlanacak; kalkınma planları ile başlayan bölge planları ve çevre düzeni planları ile devam eden hiyerarşik yapının, yerel planlama sistemi ile bütünleştirilmesiyle, kentlerimiz, çok daha sağlıklı ve güvenilir mekanlardan oluşabilecektir. Bu aynı zamanda etkin ve verimli bir afet yönetiminin de en önemli adımı olacaktır.In this study, the relationship between the planning system and disaster management has been examined in a systemic approach. The upper level planning system, one of the sub-systems of the planning system, the problems faced in the scope of disaster management within it and its points of handicap have been evaluated in the frame of reason-result. A general approach is that; the longest and effectively the most strategic part of disaster management, which is defined as a process covering the activities that need to be carried out before, during and after a disaster, is the activities carried out before a disaster. The main source of these activities is the proper functioning of the "Planning System", which begins with upper level plans and is put to practice with local level plans and the healthy selection of location for areas of settlement, hence preventing any negative effects of the disaster at the source. It is very important that the planning system work efficiently in a hierarchical structure to reduce the effects of disasters. Our cities will be much healthier and safer places when plans that is sensitive to the effects of disasters are prepared; a hierarchical structure that begins with national development plans and continues with regional and superior physical plans and is made complete with the local planning system. This at the same time will be the most important step towards an affective and efficient disaster management

The influence of artificial saliva on NiTi orthodontic wires: a study on surface characterization

Ni and Ti based alloys are prospective materials for dental orthodontic wires because of their superior mechanical properties and corrosion resistance. The studies on the corrosion resistance of these materials according to their surface characterization in artificial saliva are limited. In this study, the changes on the surface of NiTi alloy based orthodontic wires in F– and PO³₄– added or not added artificial saliva after a period of time were investigated by SEM and EDS studies.Сплави на основі Ni та Ті – перспективні для виготовлення ортодонтичних дротів завдяки своїм високим механічним характеристикам та корозійній тривкості, яка у синтетичній слині методами поверхневого аналізу досліджена недостатньо. Вивчено зміни властивостей поверхні ортодонтичних дротів із нікельтитанового сплаву під час витримки в синтетичній слині з додаванням F– та PO³₄– та без них за допомогою сканівної електронної мікроскопії (SEM) та енергодисперсійного мікроаналізу (EDS).Сплавы на основе Ni и Ті – перспективные для изготовления ортодонтичных проводов благодаря своим высоким механическим характеристикам и коррозионной стойкости, которая в синтетической слюне методами поверхностного анализа исследована недостаточно. Изучены изменения свойств поверхности ортодонтичных проводов из никельтитанового сплава во время выдержки в синтетической слюне с добавлением F– и PO³₄– и без них с помощью сканирующей электронной микроскопии (SEM) и энергодисперсионного микроанализа (EDS)

Is virtual reality a valid tool for restorative environments research?

This study examines the validity of virtual reality for assessing the restorative quality of environments. In Study 1, participants (N = 23) visited a real natural and a real urban environment, after completing a task to induce mental fatigue (i.e., a Sudoku task). We found that perceived restorative characteristics, preference ratings, experienced pleasure and self-reported restoration were higher in a real natural environment compared to a real urban environment. Perceived restorative characteristics could predict pleasure and restoration for both the real natural and urban environments, as well as preference for the real natural environment. In Study 2, participants (N = 26) visited a virtual natural and a virtual urban environment, again following a mental fatigue induction. Findings showed that virtual simulations of a natural and urban environment elicit similar effects as real counterparts of these environments. Perceived restorative characteristics, preference, pleasure and restoration were higher in a virtual natural environment compared to a virtual urban environment. Additionally, perceived restorative characteristics could predict pleasure and restoration for both the virtual natural and urban environments, and preference for the virtual natural environment. We did not find significant differences in perceived restorative characteristics between the real and virtual butterfly garden. Moreover, similar restorative characteristics predicted preference, pleasure and restoration in the real butterfly garden and the virtual butterfly garden. These findings indicate that virtual reality can be a valid tool for restorative environments research

The Effect of the Pairing Interaction on the Energies of Isobar Analog Resonances in 112−124^{112-124}Sb and Isospin Admixture in 100−124^{100-124}Sn Isotopes

In the present study, the effect of the pairing interaction and the isovector correlation between nucleons on the properties of the isobar analog resonances (IAR) in $^{112-124}$Sb isotopes and the isospin admixture in $^{100-124}$Sn isotopes is investigated within the framework of the quasiparticle random phase approximation (QRPA). The form of the interaction strength parameter is related to the shell model potential by restoring the isotopic invariance of the nuclear part of the total Hamiltonian. In this respect, the isospin admixtures in the $^{100-124}$Sn isotopes are calculated, and the dependence of the differential cross section and the volume integral $J_{F}$ for the Sn($^{3}$He,t)Sb reactions at E($^{3}$He)$=200$ MeV occurring by the excitation of IAR on mass number A is examined. Our results show that the calculated value for the isospin mixing in the $^{100}$Sn isotope is in good agreement with Colo et al.'s estimates $(4-5$, and the obtained values for the volume integral change within the error range of the value reported by Fujiwara et al. (53$\pm$5 MeV fm$^{3}$). Moreover, it is concluded that although the differential cross section of the isobar analog resonance for the ($^{3}$He,t) reactions is not sensitive to pairing correlations between nucleons, a considerable effect on the isospin admixtures in $N\approx Z$ isotopes can be seen with the presence of these correlations.Comment: 16 pages, 5 EPS figures and 2 tables, Late

YÜKSEK SICAKLIĞIN YAPI TAŞLARININ DAYANIMI ÜZERİNDEKİ ETKİSİNİN ULTRASONİK ÖLÇÜMLER İLE KESTİRİLMESİ

Natural stones have been used as a construction material since prehistoric age. Stone buildings and their protection and restoration are nowadays in the focus of interest. Natural disasters like fire can strongly damage or even may ruin these buildings. In this study, the resistance of building stones against high temperature was determined by ultrasonic measurements. The current study focuses on changes in the ultrasonic velocity of building stone subjected to simulated fire situations in the laboratory. 14 stones having different petrographical, physical and mechanical properties were used in the laboratory studies. The ultrasonic measurements and laboratory observation have shown that the texture and mineral composition of building stones are changed by heating. These changes influence the strength and durability of building stones. The evaluation of these results provides useful information when replacing damaged stone or one has to choose the suitable restoring method for the damaged part of buildings.Doğal taşlar tarih öncesi çağdan beri yapı malzemesi olarak kullanılmaktadır. Taş yapılar, bu yapıların korunması ve restorasyonu gibi konular günümüzde ilgi alanlarının odağında bulunmaktadır. Yangın gibi doğal felaketler bu yapılara çok fazla zarar verebilmekte ya da yıkılmasına neden olabilmektedir. Bu çalışmada, yapı taşlarının yüksek sıcaklığa karşı dirençleri ultrasonik ölçümler ile belirlenmeye çalışılmıştır. Mevcut çalışma, laboratuar ortamında yangına maruz kalan yapı taşlarının ultrasonik hızlarındaki değişime odaklanmıştır. Laboratuar çalışmalarında farklı petrografik, fiziksel ve mekanik özelliklere sahip 14 farklı yapı taşı kullanılmıştır. Ultrasonik ölçümler ve laboratuar gözlemleri yapı taşlarının doku ve mineral içeriğinin sıcaklık değişimine bağlı olarak değiştiğini göstermiştir. Bu değişimler yapı taşlarının dayanımını ve duraylılığını etkilemektedir. Bu sonuçların değerlendirilmesi, hasar gören taşların değiştirilmesi ve hasar gören binanın restorasyon yönteminin seçiminde, bize çok faydalı bilgiler verebilir

Two solar eclipses observations in Turkey

In thispap er, the changesin the ionosphere over Turkey due to two solar eclipses are reported. TEC on the eclipse day (26 April 1976) and the intensity of an HF radio wave during itspropagation over 567 km between Ankara and Elazıˇg on the eclipse day (11 August 1999) exhibited a very marked decrease