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Now showing 1 - 10 of 18
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    Low Carbon Architectural Design
    (Gazi Univ, 2018) Balku, Saziye; Bal Kocyigit, Filiz; Architecture; Energy Systems Engineering
    Tendency towards sustainable energy resources is increasing and leading engineers and architects make joint efforts. Renewable energy potential present in nature can be used more efficiently so that while energy consumption is reducing, rate of energy gain, on the other hand, increases by architectural design methods. A sailing club in Golbasi, Ankara is designed as a low carbon building for optimum usage of solar and wind energy. It can be concluded using an energy efficient architectural design for a building before its construction makes it possible to meet the electrical and heat energy requirements at minimum cost and environmental friendly.
  • Article
    Citation - WoS: 16
    A Gap in the Paper "a Note on Cone Metric Fixed Point Theory and Its Equivalence" [nonlinear Anal. 72(5), (2010), 2259-2261]
    (Gazi Univ, 2011) Abdeljawad, Thabet; Karapinar, Erdal
    There is a gap in Theorem 2.2 of the paper of Du [1]. In this paper, we shall state the gap and repair it.
  • Article
    Citation - WoS: 2
    Measuring Dependence Between Electricity Consumption and Economic Indicators Via Copulas: Turkish Case
    (Gazi Univ, 2018) Evkaya, O. Ozan; Yozgatligil, Ceylan; Selcuk-Kestel, A. Sevtap; Mathematics
    This paper implements copulas to identify the dependence structure between electricity consumption and its cofounding indicators. To achieve this, Turkish electricity demand, its economic and sectoral indicators are taken into account. As a first step, bivariate copulas are used to identify the best fitting copula and the degree of the dependence. Thereafter, multivariate model is established using vine copulas using highly correlated variables. The empirical results confirm the added value of the proposed approach in determining numerous tail properties. We indicate that the copulas are useful to underline, especially, the tail properties of indicators in the market for decision makers.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 10
    Comparison of Three Different Learning Methods of Multilayer Perceptron Neural Network for Wind Speed Forecasting
    (Gazi Univ, 2021) Bulut, Mehmet; Tora, Hakan; Buaisha, Dr.magdi
    In the world, electric power is the highest need for high prosperity and comfortable living standards. The security of energy supply is an essential concept in national energy management. Therefore, ensuring the security of electricity supply requires accurate estimates of electricity demand. The share of electricity generation from renewables is significantly growing in the world. This kind of energy types are dependent on weather conditions as the wind and solar energies. There are two vital requirements to locate and measure specific systems to utilize wind power: modelling and forecasting of the wind velocity. To this end, using only 4 years of measured meteorological data, the present research attempts to estimate the related speed of wind within the Libyan Mediterranean coast with the help of ANN (artificial neural networking) with three different learning algorithms, which are Levenberg-Marquardt, Bayesian Regularization and Scaled Conjugate Gradient. Conclusions reached in this study show that wind speed can be estimated within acceptable limits using a limited set of meteorological data. In the results obtained, it was seen that the SCG algorithm gave better results in tests in this study with less data.
  • Article
    Common Fixed Point Theorem for Three Mappings in Banach Valued Norm Spaces
    (Gazi Univ, 2013) Karapinar, Erdal; Moradlou, Fridoun; Salimi, Peyman; Mathematics
    In this paper, we give a generalized theorem on point of coincidence and common fixed point for three weakly compatible mappings in Banach valued norm spaces. We give a new method for construction of the sequence, which is convergence to the common fixed point of these three mappings.
  • Article
    A Modeling Approach for Designing New Acoustic Materials
    (Gazi Univ, 2024) Koçyiğit, Filiz Bal; Köse, Ercan; Buluklu, Hatice Mehtap
    In this study, mathematical modeling design based on Sound Transmission Loss measurement results of new acoustic material samples with natural content was carried out. Using the test samples in question, transfer function of acoustic materials based on electronic filter circuit design and a transition design method for the production of new acoustic materials by utilizing the transfer function is presented. Based on the experimental results of the test samples, it is the most suitable low-pass filter structure for the proposed design. In this study, active Sallen-Key low-pass filter structure is preferred and used. Sound Transmission Losses in dB (decibels) of acoustic samples were obtained experimentally for 500, 1000, 2000 and 4000 Hz. fundamental frequencies in the literature. Based on these data, transfer function simulation suppression gain results were obtained in TINA-TI program, active filter circuit designed, and MATLAB program. When the other results were compared in the experimental results, it was seen that very close values were obtained. It has been demonstrated that the proposed method can be used effectively in the design and examination of new acoustic materials.
  • Article
    Citation - WoS: 3
    On the Yielding of Two-Layer Composite Spherical Pressure Vessels
    (Gazi Univ, 2017) Akis, Tolga
    The yielding of two-layer composite spherical pressure vessels under either internal or external pressure is investigated analytically in the framework of small deformations and von Mises yield criterion. It is shown for both pressure cases that depending on the material properties and sphere dimensions, different modes of plasticization may take place. Unlike the deformation behavior of a single layer spherical pressure vessel, yielding may commence at the inner layer or at the outer layer or simultaneously at both layers of the assembly.
  • Article
    Citation - WoS: 1
    Zero Consumption Monotype Education Buildings
    (Gazi Univ, 2018) Bal Kocyigit, Filiz
    Turkey has mainly seven geographic zones but four climatic zones. Major influence on energy usage and educational buildings which perform well in energy terms will reap significant environmental and economic benefits for years to come. The lack of electric, heating-cooling and lighting comfort in the structure reduce the quality of education. Many village schools cannot provide training in enough conditions. Municipalities are preparing "Type School Project" for government schools, without thinking different zones conditions, directions and heights. At this stage, there arises importance of the Architectural Design Process for typical energy efficient design which can easily adapt to the location. The material must not only be transmits about 70-90% of solar radiation, but also its insulation quality. Additionally architectural form of building must be affected to take all solar energy, wind and water. In this study, architectural design method has been used for energy gain from transparent insulated trombe wall. And have been calculated in accordance with their manners in the middle, south, noth, east and west regions of Anatolia which are located in different degree-days regions on the basis of TS 825.
  • Article
    Citation - WoS: 3
    Flexural Behavior of Reinforced Concrete Beams With Various Layers of Conventional and Steel Fiber Reinforced Concrete
    (Gazi Univ, 2022) Mertol, Halit Cenan
    Flexural behavior of reinforced concrete (RC) beams having various layers of conventional concrete (CC) and steel fiber reinforced concrete (SFRC) were investigated in this study. Two groups of five beams (180x250x3500 mm) were tested under four-point loading to evaluate the flexural behavior. Both of these groups of beams were reinforced with 4 phi 16 reinforcing bars. The main variable in this research was the concrete type of the layers throughout the height of the specimen. The height of the cross-section of the beams was divided into 5 layers, each having 50 mm thicknesses. In group "F" specimens, SFRC layers were added to the layers of a CC beam, starting from the bottom, as replacements of CC layers, i.e. F15P10 represented that the bottom 150 mm was cast using SFRC whereas the top 100 mm was cast using CC. In group "P" specimens, CC layers were added to the layers of a SFRC beam, starting from the bottom, as replacements of SFRC layers, i.e. P10F15 represented that the bottom 100 mm was cast using CC whereas the top 150 mm was cast using SFRC. Experimental load-deflection curves were evaluated based on ultimate load, service/post-peak stiffnesses, and flexural toughness. It can be concluded that reasonable ductility may be achieved by adding SFRC at the tension side no matter how thick the layer is and where it is located.
  • Article
    The Estimation of the Residual Shear Strength of High Plastic Clays Based on Direct Shear Test Results
    (Gazi Univ, 2021) Akis, Ebru
    Landslides are the most common incidents with a rate of 45% considering the distribution of natural disaster numbers to disaster types. In order to make remedial measures for the landslides, the residual shear strength parameters formed in the shear plane during the landslide must be estimated as close to the reality as possible. These parameters can be determined by multi-reversal direct shear, ring shear tests, back calculations, correlations in the literature by means of physical properties of the soil. The difficulty of predicting the groundwater conditions during landslide is obvious and it directly affects the residual shear strength values when shear strength parameters are determined using the back analysis method. On the other hand, residual shear strength parameters obtained from the literature can give a wide range. Besides, ring shear tests are not commonly performed in laboratories and depending on the type of soil, multi reveral direct shear tests may need to be performed at very low speeds. Relatively long test time adversely affects the practical use of the multi reversal direct shear tests. In this study, the relationship between peak and residual shear strength in normally consolidated high plastic clays was studied within the framework of the above restrictions. Firstly, the empirical correlation between the residual shear strength and the index porperties and peak shear strength was predicted by evaluating the results of the studies in our country's literature. Then, the results obtained from the multi reversal direct shear tests with remoulded high plastic clay samples and the predicted values were compared.