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Trabzon, Turkey

Karadeniz Technical University , is a public research university in Trabzon, in the Black Sea region of Turkey. Established in 1955, it is the fourth oldest university in Turkey. Wikipedia.

The Hercynian Köse composite pluton (KCP) is located in the Eastern Pontides, Turkey, and consists of two units of high-K calc-alkaline, primarily peraluminous granites: (i) the internal body, and (ii) the external body. The internal body, which was emplaced at 322-318Ma (40Ar/39Ar ages on biotite and hornblende, respectively), displays a wide compositional range (49-71wt.% SiO2) and contains several lithologies: hybrid equigranular rocks, microgranular magmatic enclaves, mafic dikes, porphyry dikes and mylonites. The external body, which was emplaced at 306.7Ma (40Ar/39Ar age on K-feldspar), consists exclusively of monzogranite (>71wt.% SiO2). Field relationships, mineralogy, major- and trace element geochemistry, and initial Sr-Nd isotope values (ISr=0.70821 to 0.71002, eNd(t)=-6.6 to -8.0) show that the internal body was differentiated and evolved by crystal fractionation and magma mixing processes. The end-members of the mixing process were a mafic rock and a felsic rock. Mafic magma was derived from a relatively deep-seated (25-30km) crustal storage reservoir, not directly from the mantle, and underwent significant differentiation by fractional crystallization and crustal contamination before mixing. In addition, these magma storages probably supplied the additional heat necessary to initiate crustal melting. Some of the additional heat may have also been released by the radiogenic decay of heat producing elements. Eventually, the existing felsic magma from the melting of K-bearing meta-greywackes was raised to its emplacement level at a depth of ~10-16km. After partial crystallization, it was sporadically intruded by modified mafic magma from the deeper crustal reservoir to generate hybrid rocks. The hybrid rocks were then elevated to a shallower depth by normal faults during the collapse of the orogen and erosion. Mylonites that were later overprinted by pseudotachylites are typically constrained to the internal body and are regarded as markers of this event. The external body is characterized by a significantly less radiogenic and limited range of Sr-Nd isotope values (ISr=0.70639 to 0. 70792, eNd(t)=-4.4 to -6.5) than those of the internal body and a lack of rocks documenting the open system differentiation processes. Fractional crystallization is the exclusive process responsible for the elemental range within the body. The rocks also contain less biotite relative to those of the internal body. All these involve less K-bearing mid-crustal rocks (orthogneisses) in their source, which was probably located at depths near the lower crust. The absence of purely lower crustal-derived melts can be explained by the removal of this type of material during the formation of the parental melt. This melt later ascended to its emplacement level at a depth of around ~5-10km and cut the hybrid rocks of the internal body and regional metamorphic rocks that had been raised previously due to ongoing erosion. The melt that injected into the cracks of the internal body crystallized into porphyries because there was not enough time for the entire crystallization of magma. The data presented here indicate that late Early Carboniferous and Late Carboniferous magmatism occurred in a collisional setting. Slab detachment and subsequent delamination seem to be the most plausible mechanisms for the generation of the Hercynian high-K calc-alkaline magmatism in the Eastern Pontides, Turkey. © 2010 International Association for Gondwana Research. Source

Kaygusuz K.,Karadeniz Technical University
Renewable and Sustainable Energy Reviews | Year: 2012

Today, there are 1.4 billion people around the world that lack access to electricity, some 85% of them in rural areas. Without additional dedicated policies, by 2030 the number of people drops, but only to 1.2 billion. Some 15% of the world's population still lack access, the majority of them living in Sub-Saharan Africa. The number of people relying on the traditional use of biomass is projected to rise from 2.7 billion today to 2.8 billion in 2030. Addressing these inequities depends upon international recognition that the projected situation is intolerable, a commitment to effect the necessary change, and setting targets and indicators to monitor progress. A new financial, institutional and technological framework is required, as is capacity building in order to dramatically scale up access to modern energy services at the local and regional levels. In this paper, we discussed the energy situation of the developing countries for sustainable development. © 2011 Elsevier Ltd. All rights reserved. Source

The main purpose of this study is to compare the use of logistic regression, multi-criteria decision analysis, and a likelihood ratio model to map landslide susceptibility in and around the city of İzmir in western Turkey. Parameters, such as lithology, slope gradient, slope aspect, faults, drainage lines, and roads, were considered. Landslide susceptibility maps were produced using each of the three methods and then compared and validated. Before the modeling and validation, the observed landslides were separated into two groups. The first group was for training, and the other group was for validation steps. The accuracy of models was measured by fitting them to a validation set of observed landslides. For validation process, the area under curvature (AUC) approach was applied. According to the AUC values of 0.810, 0.764, and 0.710 for logistic regression, likelihood ratio, and multi-criteria decision analysis, respectively, logistic regression was determined to be the most accurate method among the other used landslide susceptibility mapping methods. Based on these results, logistic regression and likelihood ratio models can be used to mitigate hazards related to landslides and to aid in land-use planning. © 2011 Springer-Verlag. Source

Sahin Y.,Karadeniz Technical University
Energy Education Science and Technology Part A: Energy Science and Research | Year: 2011

Today world is facing three critical problems: (1) high fuel prices, (2) climatic changes, (3) air pollution. There are several reasons for biofuels to be considered as relevant technologies by both developing and industrialized countries. They include energy security reasons, environmental concerns, foreign exchange savings, and socioeconomic issues related to the rural sectors of all countries in the world. The main advantages of using biomass and biomass derivatives in energy production are low sulfur, nitrogen and metal content and neutral CO 2. Most traditional biofuels, such as ethanol from corn, wheat, or sugar beets, and biodiesel from oil seeds, are produced from classic agricultural food crops that require high-quality agricultural land for growth. Land use impacts were related to the area of land used, physical land use. Biofuels are oxygenated compounds. The oxygenated compounds such as ethanol, methanol and biodiesel provide more efficient combustion, and cleaner emissions. Most traditional biofuels, such as ethanol from corn, wheat, or sugar beets, and biodiesel from oil seeds, are produced from classic agricultural food crops that require high-quality agricultural land for growth. Aspect of impact category land use is an important parameter for biomass energy. This impact category describes the environmental impact resulting from land use for human activities. Results indicate that the transformations of biofuels are greater than those of fossil fuels, thus showing that a larger amount of resources is required to get the environmental friendly product. Ethanol made from biomass provides unique environmental, economic strategic benefits and can be considered as a safe and cleanest liquid fuel alternative to fossil fuels Neat biodiesel and biodiesel blends reduce particulate matter (PM), hydrocarbons (HC) and carbon monoxide (CO) emissions and increase nitrogen oxides (NO x) emissions compared with diesel fuel used in an unmodified diesel engine. © Sila Science. Source

Togan V.,Karadeniz Technical University
Engineering Structures | Year: 2012

This paper presents a design procedure employing a Teaching-Learning Based Optimization (TLBO) technique for discrete optimization of planar steel frames. TLBO is a nature-inspired search method that has been developed recently. It simulates the social interaction between the teacher and the learners in a class, which is summarized as teaching-learning process. The design algorithm aims to obtain minimum weight frames subjected to strength and displacement requirements imposed by the American Institute for Steel Construction (AISC) Load and Resistance Factor Design (LRFD). Designs are obtained selecting appropriate W-shaped sections from a standard set of steel sections specified by the AISC. Several frame examples from the literature are examined to verify the suitability of the design procedure and to demonstrate the effectiveness and robustness of the TLBO creating of an optimal design for frame structures. The results of the TLBO are compared to those of the genetic algorithm (GA), the ant colony optimization (ACO), the harmony search (HS) and the improved ant colony optimization (IACO) and they shows that TLBO is a powerful search and applicable optimization method for the problem of engineering design applications. © 2011 Elsevier Ltd. Source

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