Search results for: Murat Bakir
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 41

Search results for: Murat Bakir

41 Carvacrol Attenuates Lung Injury in Rats with Severe Acute Pancreatitis

Authors: Salim Cerig, Fatime Geyikoglu, Pınar Akpulat, Suat Colak, Hasan Turkez, Murat Bakir, Mirkhalil Hosseinigouzdagani, Kubra Koc

Abstract:

This study was designed to evaluate whether carvacrol (CAR) could provide protection against lung injury by acute pancreatitis development. The rats were randomized into groups to receive (I) no therapy; (II) 50 μg/kg cerulein at 1h intervals by four intraperitoneal injections (i.p.); (III) 50, 100 and 200 mg/kg CAR by one i.p.; and (IV) cerulein+CAR after 2h of cerulein injection. 12h later, serum samples were obtained to assess pancreatic function the lipase and amylase values. The animals were euthanized and lung samples were excised. The specimens were stained with hematoxylin-eosin (H&E), periodic acid–Schif (PAS), Mallory's trichrome and amyloid. Additionally, oxidative DNA damage was determined by measuring as increases in 8-hydroxy-deoxyguanosine (8-OH-dG) adducts. The results showed that the serum activity of lipase and amylase in AP rats were significantly reduced after the therapy (p<0.05). We also found that the 100 mg/kg dose of CAR significantly decreased 8-OH-dG levels. Moreover, the severe pathological findings in the lung such as necrosis, inflammation, congestion, fibrosis, and thickened alveolar septum were attenuated in the AP+CAR groups when compared with AP group. Finally, the magnitude of the protective effect on lung is certain, and CAR is an effective therapy for lung injury caused by AP.

Keywords: Antioxidant activity, carvacrol, experimental acute pancreatitis, lung injury, oxidative DNA damage.

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40 Hepatoprotective Effect of Oleuropein against Cisplatin-Induced Liver Damage in Rat

Authors: Salim Cerig, Fatime Geyikoglu, Murat Bakir, Suat Colak, Merve Sonmez, Kubra Koc

Abstract:

Cisplatin (CIS) is one of the most effective an anticancer drug and also toxic to cells by activating oxidative stress. Oleuropein (OLE) has key role against oxidative stress in mammalian cells, but the role of this antioxidant in the toxicity of CIS remains unknown. The aim of the present study was to investigate the efficacy of OLE on CIS-induced liver damages in male rats. With this aim, male Sprague Dawley rats were randomly assigned to one of eight groups: Control group; the group treated with 7 mg/kg/day CIS; the groups treated with 50, 100 and 200 mg/kg/day OLE (i.p.); and the groups treated with OLE for three days starting at 24 h following CIS injection. After 4 days of injections, serum was provided to assess the blood AST, ALT and LDH values. The liver tissues were removed for histological, biochemical (TAC, TOS and MDA) and genotoxic evaluations. In the CIS treated group, the whole liver tissue showed significant histological changes. Also, CIS significantly increased both the incidence of oxidative stress and the induction of 8-hydroxy-deoxyguanosine (8-OH-dG). Moreover, the rats taking CIS have abnormal results on liver function tests. However, these parameters reached to the normal range after administration of OLE for 3 days. Finally, OLE demonstrated an acceptable high potential and was effective in attenuating CIS-induced liver injury. In this trial, the 200 mg/kg dose of OLE firstly appeared to induce the most optimal protective response.

Keywords: Antioxidant response, cisplatin, histology, liver, oleuropein, 8-OhdG.

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39 Autonomous Flight Performance Improvement of Load-Carrying Unmanned Aerial Vehicles by Active Morphing

Authors: Tugrul Oktay, Mehmet Konar, Mohamed Abdallah Mohamed, Murat Aydin, Firat Sal, Murat Onay, Mustafa Soylak

Abstract:

In this paper, it is aimed to improve autonomous flight performance of a load-carrying (payload: 3 kg and total: 6kg) unmanned aerial vehicle (UAV) through active wing and horizontal tail active morphing and also integrated autopilot system parameters (i.e. P, I, D gains) and UAV parameters (i.e. extension ratios of wing and horizontal tail during flight) design. For this purpose, a loadcarrying UAV (i.e. ZANKA-II) is manufactured in Erciyes University, College of Aviation, Model Aircraft Laboratory is benefited. Optimum values of UAV parameters and autopilot parameters are obtained using a stochastic optimization method. Using this approach autonomous flight performance of UAV is substantially improved and also in some adverse weather conditions an opportunity for safe flight is satisfied. Active morphing and integrated design approach gives confidence, high performance and easy-utility request of UAV users.

Keywords: Unmanned aerial vehicles, morphing, autopilots, autonomous performance.

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38 A Semi-Classical Signal Analysis Method for the Analysis of Turbomachinery Flow Unsteadiness

Authors: Fadi Eleiwi, Taous Meriem Laleg-Kirati, Sofiane Khelladi, Farid Bakir

Abstract:

This paper presents the use of a semi-classical signal analysis method that has been developed recently for the analysis of turbomachinery flow unsteadiness. We will focus on the correlation between theSemi-Classical Signal Analysis parameters and some physical parameters in relation with turbomachinery features. To demonstrate the potential of the proposed approach, a static pressure signal issued from a rotor/stator interaction of a centrifugal pump is studied. Several configurations of the pump are compared.

Keywords: Semi-classical signal analysis, turbomachines, newindices, physical parameters

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37 On Suborbital Graphs of the Congruence Subgroup r 0(N)

Authors: Bahadir O. Guler, Serkan Kader, Murat Besenk

Abstract:

In this paper we examine some properties of suborbital graphs for the congruence subgroup r 0 (N) . Then we give necessary and sufficient conditions for graphs to have triangels.

Keywords: Congruence subgroup, Imprimitive action, Modulargroup, Suborbital graphs.

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36 The Slant Helices According to Bishop Frame

Authors: Bahaddin Bukcu, Murat Kemal Karacan

Abstract:

In this study, we have defined slant helix according to Bishop frame in Euclidean 3-Space. Furthermore, we have given some necassary and sufficient conditons for the slant helix.

Keywords: Slant helix, Bishop frame, Parallel transport frame

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35 Neural Network Controller for Mobile Robot Motion Control

Authors: Jasmin Velagic, Nedim Osmic, Bakir Lacevic

Abstract:

In this paper the neural network-based controller is designed for motion control of a mobile robot. This paper treats the problems of trajectory following and posture stabilization of the mobile robot with nonholonomic constraints. For this purpose the recurrent neural network with one hidden layer is used. It learns relationship between linear velocities and error positions of the mobile robot. This neural network is trained on-line using the backpropagation optimization algorithm with an adaptive learning rate. The optimization algorithm is performed at each sample time to compute the optimal control inputs. The performance of the proposed system is investigated using a kinematic model of the mobile robot.

Keywords: Mobile robot, kinematic model, neural network, motion control, adaptive learning rate.

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34 Evaluation of Water Quality for the Kurtbogazi Dam Outlet and the Streams Feeding the Dam in Ankara, Turkey

Authors: G. Tozsin, F. Bakir, C. Acar, E. Koç

Abstract:

Kurtbogazi Dam has gained special meaning for Ankara, Turkey for the last decade due to the rapid depletion of nearby resources of drinking water. In this study, the results of the analyses of Kurtbogazi Dam outlet water and the rivers flowing into the Kurtbogazi Dam were discussed for the period of last five years between 2008 and 2012. Some physical and chemical properties (pH, temperature, biochemical oxygen demand (BOD5), nitrate, phosphate and chlorine) of these water resources were evaluated. They were classified according to the Council Directive (75/440/EEC). Moreover, the properties of these surface waters were assessed to determine the quality of water for drinking and irrigation purposes using Piper, US Salinity Laboratory and Wilcox diagrams. The results showed that all the water resources are acceptable level as surface water except for Pazar Stream in terms of ortho-phosphate and BOD5 concentration for 2008.

Keywords: Kurtbogazi dam, water quality assessment, Ankara water, water supply.

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33 The New Effective Biostimulator for Agroecological Engineering

Authors: Saniyam A. Ibragimova, Zhandos M. Basygarayev, Almagul R. Kerimkulova, E. A. Bukenova, Murat K. Gilmanov

Abstract:

New biostimulator from wheat seeds which by its chemical composition relates to fusicoccin is presented in this article. New biostimulator could be used as powerful hormonal substance that has ability to increase productivity and salt tolerance of agricultural plants. Also on the basis of biostimulator we have developed vegetative method for fast reproduction of perennial plants as desert plant - Tamarix gracilis.

Keywords: Biostimulator, crop productivity, ecology, fussicoccin, salt tolerance.

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32 A Mixture Model of Two Different Distributions Approach to the Analysis of Heterogeneous Survival Data

Authors: Ülkü Erişoğlu, Murat Erişoğlu, Hamza Erol

Abstract:

In this paper we propose a mixture of two different distributions such as Exponential-Gamma, Exponential-Weibull and Gamma-Weibull to model heterogeneous survival data. Various properties of the proposed mixture of two different distributions are discussed. Maximum likelihood estimations of the parameters are obtained by using the EM algorithm. Illustrative example based on real data are also given.

Keywords: Exponential-Gamma, Exponential-Weibull, Gamma-Weibull, EM Algorithm, Survival Analysis.

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31 Financial Problems Met in the Tourism Sector in Turkey: A Survey on the Tourism Businesses

Authors: Raif Parlakkaya, Huseyin Cetin, Halil Akmese, Mesut Murat Adabali

Abstract:

As the economies of other countries in the Mediterranean Basin, the tourism sector in our country has a high denominator in economics. Tourism businesses, which are building blocks of tourism, sector faces with a variety of problems during their activities. These problems faced make business efficiency and competition conditions of the businesses difficult. Most of the problems faced by the tourism businesses and the information of consumers about consumers’ rights were used in this study, which is conducted to determine the problems of tourism businesses in the Central Anatolia Region. It is aimed to contribute the awareness of staff and executives working at tourism sector and to attract attention of businesses active concurrently with tourism sector and legislators.

Keywords: Financial Problems, The problems of Tourism businesses, Tourism Businesses, Tourism Sector in Turkey.

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30 Assessment of Collapse Potential of Degrading SDOF Systems

Authors: Muzaffer Borekci, Murat S. Kirçil

Abstract:

Predicting the collapse potential of a structure during earthquakes is an important issue in earthquake engineering. Many researchers proposed different methods to assess the collapse potential of structures under the effect of strong ground motions. However most of them did not consider degradation and softening effect in hysteretic behavior. In this study, collapse potential of SDOF systems caused by dynamic instability with stiffness and strength degradation has been investigated. An equation was proposed for the estimation of collapse period of SDOF system which is a limit value of period for dynamic instability. If period of the considered SDOF system is shorter than the collapse period then the relevant system exhibits dynamic instability and collapse occurs.

Keywords: Collapse, degradation, dynamic instability, seismic response.

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29 Causes of Construction Delays in Qatar Construction Projects

Authors: Murat Gunduz, Mohanad H. A. AbuHassan

Abstract:

Construction industry mainly focuses on the superstructure, infrastructure, and oil and gas industry. The development of infrastructure projects in developing countries attracted a lot of foreign construction contractors, consultants, suppliers and diversified workforce to interfere and to be evolved in such huge investment. Reducing worksite delays in such projects require knowledge and attention. Therefore, it is important to identify the influencing delay attributes affecting construction projects. The significant project factors affecting construction delays were investigated. Data collection was carried out through an online web survey system to capture significant factors. Significant factors were determined with importance index and relevant recommendations are made. The output of the data analysis would lead the industry experts better assess the impact of construction delays on construction projects.

Keywords: Construction industry, delays, importance index.

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28 Increasing Performance of Autopilot Guided Small Unmanned Helicopter

Authors: Tugrul Oktay, Mehmet Konar, Mustafa Soylak, Firat Sal, Murat Onay, Orhan Kizilkaya

Abstract:

In this paper, autonomous performance of a small manufactured unmanned helicopter is tried to be increased. For this purpose, a small unmanned helicopter is manufactured in Erciyes University, Faculty of Aeronautics and Astronautics. It is called as ZANKA-Heli-I. For performance maximization, autopilot parameters are determined via minimizing a cost function consisting of flight performance parameters such as settling time, rise time, overshoot during trajectory tracking. For this purpose, a stochastic optimization method named as simultaneous perturbation stochastic approximation is benefited. Using this approach, considerable autonomous performance increase (around %23) is obtained.

Keywords: Small helicopters, hierarchical control, stochastic optimization, autonomous performance maximization, autopilots.

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27 Study of the Effect of the Contra-Rotating Component on the Performance of the Centrifugal Compressor

Authors: Van Thang Nguyen, Amelie Danlos, Richard Paridaens, Farid Bakir

Abstract:

This article presents a study of the effect of a contra-rotating component on the efficiency of centrifugal compressors. A contra-rotating centrifugal compressor (CRCC) is constructed using two independent rotors, rotating in the opposite direction and replacing the single rotor of a conventional centrifugal compressor (REF). To respect the geometrical parameters of the REF one, two rotors of the CRCC are designed, based on a single rotor geometry, using the hub and shroud length ratio parameter of the meridional contour. Firstly, the first rotor is designed by choosing a value of length ratio. Then, the second rotor is calculated to be adapted to the fluid flow of the first rotor according aerodynamics principles. In this study, four values of length ratios 0.3, 0.4, 0.5, and 0.6 are used to create four configurations CF1, CF2, CF3, and CF4 respectively. For comparison purpose, the circumferential velocity at the outlet of the REF and the CRCC are preserved, which means that the single rotor of the REF and the second rotor of the CRCC rotate with the same speed of 16000rpm. The speed of the first rotor in this case is chosen to be equal to the speed of the second rotor. The CFD simulation is conducted to compare the performance of the CRCC and the REF with the same boundary conditions. The results show that the configuration with a higher length ratio gives higher pressure rise. However, its efficiency is lower. An investigation over the entire operating range shows that the CF1 is the best configuration in this case. In addition, the CRCC can improve the pressure rise as well as the efficiency by changing the speed of each rotor independently. The results of changing the first rotor speed show with a 130% speed increase, the pressure ratio rises of 8.7% while the efficiency remains stable at the flow rate of the design operating point.

Keywords: Centrifugal compressor, contra-rotating, interaction rotor, vacuum.

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26 Weight Comparison of Oil and Dry Type Distribution Transformers

Authors: Murat Toren, Mehmet Çelebi

Abstract:

Reducing the weight of transformers while providing good performance, cost reduction and increased efficiency is important. Weight is one of the most significant factors in all electrical machines, and as such, many transformer design parameters are related to weight calculations. This study presents a comparison of the weight of oil type transformers and dry type transformer weight. Oil type transformers are mainly used in industry; however, dry type transformers are becoming more widespread in recent years. MATLAB is typically used for designing transformers and design parameters (rated voltages, core loss, etc.) along with design in ANSYS Maxwell. Similar to other studies, this study presented that the dry type transformer option is limited. Moreover, the commonly-used 50 kVA distribution transformers in the industry are oil type and dry type transformers are designed and considered in terms of weight. Currently, the preference for low-cost oil-type transformers would change if costs for dry-type transformer were more competitive. The aim of this study was to compare the weight of transformers, which is a substantial cost factor, and to provide an evaluation about increasing the use of dry type transformers.

Keywords: Weight, oil-type transformers, dry-type transformers.

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25 Self Organizing Mixture Network in Mixture Discriminant Analysis: An Experimental Study

Authors: Nazif Çalış, Murat Erişoğlu, Hamza Erol, Tayfun Servi

Abstract:

In the recent works related with mixture discriminant analysis (MDA), expectation and maximization (EM) algorithm is used to estimate parameters of Gaussian mixtures. But, initial values of EM algorithm affect the final parameters- estimates. Also, when EM algorithm is applied two times, for the same data set, it can be give different results for the estimate of parameters and this affect the classification accuracy of MDA. Forthcoming this problem, we use Self Organizing Mixture Network (SOMN) algorithm to estimate parameters of Gaussians mixtures in MDA that SOMN is more robust when random the initial values of the parameters are used [5]. We show effectiveness of this method on popular simulated waveform datasets and real glass data set.

Keywords: Self Organizing Mixture Network, MixtureDiscriminant Analysis, Waveform Datasets, Glass Identification, Mixture of Multivariate Normal Distributions

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24 Impact of Fly Ash-Based Geopolymer Modification on the High-Temperature Properties of Bitumen

Authors: Burak Yigit Katanalp, Murat Tastan, Perviz Ahmedzade, Çigdem Canbay Turkyilmaz, Emrah Turkyilmaz

Abstract:

This study evaluated the mechanical and rheological performance of fly ash-based geopolymer at high temperatures. A series of laboratory tests were conducted on neat bitumen and three modified bitumen samples, which incorporated fly ash-based geopolymer at various percentages. Low-calcium fly ash was used as the alumina-silica source. The dynamic shear rheometer and rotational viscometer were employed to determine high-temperature properties, while conventional tests such as penetration and softening point were used to evaluate the physical properties of bitumen. Short-term aging resistance of the samples was assessed using the rolling thin film oven. The results show that geopolymer has a compromising effect on bitumen properties, with improved stiffness, enhanced mechanical strength, and increased thermal susceptibility of the asphalt binder.

Keywords: Bitumen, geopolymer, rutting, dynamic mechanical analysis.

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23 Analysis of Critical Success Factors of Six Sigma in Pakistani Small and Medium-Sized Enterprises

Authors: Zanjbeel Tabassum, Cahit Ali Bayraktar, Asfa Muhammad Din, Murat Durucu

Abstract:

Six Sigma is a widely adapted quality improvement methodology applied throughout the world. Through this paper, an attempt has been made to identify Critical Success Factors (CSF) for successful implementation of Six Sigma in Pakistani Small and Medium-sized Enterprises (SMEs). A survey methodology was used to collect the data from SMEs in Pakistan. The results of this exploratory empirical research reflect the importance of different CSFs of Six Sigma implementation in SMEs in Pakistan. On the basis of extracted factors, a framework has been proposed for successful Six Sigma implementation in Pakistani SMEs. This study will provide a base for Pakistani SMEs and future researchers working in Six Sigma implementation and help them to prepare a road map to eradicate the hurdles in Six Sigma implementation.

Keywords: Critical success factors, small and medium-sized enterprises, Six Sigma, Pakistan.

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22 Examining of Tool Wear in Cryogenic Machining of Cobalt-Based Haynes 25 Superalloy

Authors: Murat Sarıkaya, Abdulkadir Güllü

Abstract:

Haynes 25 alloy (also known as L-605 alloy) is cobalt based super alloy which has widely applications such as aerospace industry, turbine and furnace parts, power generators and heat exchangers and petroleum refining components due to its excellent characteristics. However, the workability of this alloy is more difficult compared to normal steels or even stainless. In present work, an experimental investigation was performed under cryogenic cooling to determine cutting tool wear patterns and obtain optimal cutting parameters in turning of cobalt based superalloy Haynes 25. In experiments, uncoated carbide tool was used and cutting speed (V) and feed rate (f) were considered as test parameters. Tool wear (VBmax) were measured for process performance indicators. Analysis of variance (ANOVA) was performed to determine the importance of machining parameters.

Keywords: Cryogenic machining, difficult-to-cut alloy, tool wear, turning.

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21 Analysis of a Population of Diabetic Patients Databases with Classifiers

Authors: Murat Koklu, Yavuz Unal

Abstract:

Data mining can be called as a technique to extract information from data. It is the process of obtaining hidden information and then turning it into qualified knowledge by statistical and artificial intelligence technique. One of its application areas is medical area to form decision support systems for diagnosis just by inventing meaningful information from given medical data. In this study a decision support system for diagnosis of illness that make use of data mining and three different artificial intelligence classifier algorithms namely Multilayer Perceptron, Naive Bayes Classifier and J.48. Pima Indian dataset of UCI Machine Learning Repository was used. This dataset includes urinary and blood test results of 768 patients. These test results consist of 8 different feature vectors. Obtained classifying results were compared with the previous studies. The suggestions for future studies were presented.

Keywords: Artificial Intelligence, Classifiers, Data Mining, Diabetic Patients.

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20 Determining Earthquake Performances of Existing Reinforced Concrete Buildings by Using ANN

Authors: Musa H. Arslan, Murat Ceylan, Tayfun Koyuncu

Abstract:

In this study, an Artificial Neural Network (ANN) analytical method has been developed for analyzing earthquake performances of the Reinforced Concrete (RC) buildings. 66 RC buildings with four to ten storeys were subjected to performance analysis according to the parameters which are the existing material, loading and geometrical characteristics of the buildings. The selected parameters have been thought to be effective on the performance of RC buildings. In the performance analyses stage of the study, level of performance possible to be shown by these buildings in case of an earthquake was determined on the basis of the 4-grade performance levels specified in Turkish Earthquake Code-2007 (TEC-2007). After obtaining the 4-grade performance level, selected 23 parameters of each building have been matched with the performance level. In this stage, ANN-based fast evaluation algorithm mentioned above made an economic and rapid evaluation of four to ten storey RC buildings. According to the study, the prediction accuracy of ANN has been found about 74%.

Keywords: Artificial neural network, earthquake, performance, reinforced concrete.

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19 Researches on Attractive Flowered Natural Woody Plants of Bursa Flora in Terms of Landscape Design

Authors: Elvan Ender, Murat Zencirkıran

Abstract:

One of the most important criteria that increase the success of design in landscape architecture is the visual effect. The characteristics that affect visual appearance in plant design vary depending on the phenological periods of the plants. In plants, although different effects are observed in different periods of the year, this effect is felt most prominently in flowering periods. For this reason, knowing the flowering time, duration and flower characteristics should be considered as a factor increasing the success of plant design. In this study, flower characteristics of natural woody plants with attractive flowers have been examined. Because of the variability of these characteristics of plants in the region, consideration of these criteria in the planting design processes in the region may increase the success of the design. At the same time, when species selection is made considering the obtained data, visuality and sustainability of natural species can be possible in Bursa city with planting design.

Keywords: Bursa, flower characteristics, natural plants, planting design.

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18 Thermal Performance Analysis of Nanofluids in a Concetric Heat Exchanger Equipped with Turbulators

Authors: Feyza Eda Akyurek, Bayram Sahin, Kadir Gelis, Eyuphan Manay, Murat Ceylan

Abstract:

Turbulent forced convection heat transfer and pressure drop characteristics of Al2O3–water nanofluid flowing through a concentric tube heat exchanger with and without coiled wire turbulators were studied experimentally. The experiments were conducted in the Reynolds number ranging from 4000 to 20000, particle volume concentrations of 0.8 vol.% and 1.6 vol.%. Two turbulators with the pitches of 25 mm and 39 mm were used. The results of nanofluids indicated that average Nusselt number increased much more with increasing Reynolds number compared to that of pure water. Thermal conductivity enhancement by the nanofluids resulted in heat transfer enhancement. Once the pressure drop of the alumina/water nanofluid was analyzed, it was nearly equal to that of pure water at the same Reynolds number range. It was concluded that nanofluids with the volume fractions of 0.8 and 1.6 did not have a significant effect on pressure drop change. However, the use of wire coils in heat exchanger enhanced heat transfer as well as the pressure drop.

Keywords: Turbulators, heat exchanger, nanofluids, heat transfer enhancement.

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17 Role of Sodium Concentration, Waiting Time and Constituents’ Temperature on the Rheological Behavior of Alkali Activated Slag Concrete

Authors: Muhammet M. Erdem, Erdoğan Özbay, Ibrahim H. Durmuş, Mustafa Erdemir, Murat Bikçe, Müzeyyen Balçıkanlı

Abstract:

In this paper, rheological behavior of alkali activated slag concretes were investigated depending on the sodium concentration (SC), waiting time (WT) after production, and constituents’ temperature (CT) parameters. For this purpose, an experimental program was conducted with four different SCs of 1.85, 3.0, 4.15, and 5.30%, three different WT of 0 (just after production), 15, and 30 minutes and three different CT of 18, 30, and 40 °C. Solid precursors are activated by water glass and sodium hydroxide solutions with silicate modulus (Ms = SiO2/Na2O) of 1. Slag content and (water + activator solution)/slag ratio were kept constant in all mixtures. Yield stress and plastic viscosity values were defined for each mixture by using the ICAR rheometer. Test results were demonstrated that all of the three studied parameters have tremendous effect on the yield stress and plastic viscosity values of the alkali activated slag concretes. Increasing the SC, WT, and CT drastically augmented the rheological parameters. At the 15 and 30 minutes WT after production, most of the alkali activated slag concretes were set instantaneously, and rheological measurements were not performed.

Keywords: Alkali activation, slag, rheology, yield stress, plastic viscosity.

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16 The Impact of Bayh-Dole Act on Knowledge Transfer in the States and a Study on Applicability in Turkey

Authors: Murat Sengoz, Mustafa Kemal Topcu

Abstract:

This study aims to contribute to efforts of Turkey to increase research and development to overcome mid-income level trap by discussing regulations on patenting and licensing. Knowledge and technology transfer from universities to business world is attached great significance to increase innovation. Through literature survey, it is observed that the States accomplished to boost the economy and increase welfare by the Bayh-Dole Act enacted in 1980. Thus, this good practice is imitated by other nations to make technological developments. The Act allows universities to acquire patent right in research programs funded by government to increase technology transfer from universities whilst motivating real sector to use research pools in the universities. An act similar with Bayh-Dole could be beneficial to Turkey since efforts in Turkey are to promote research, development and innovation. Towards this end, the impact of Bayh-Dole Act on the patent system for universities in the Sates is deliberately examined, applicability in Turkey is discussed. However, it is conceded that success rate of applying Bayh-Dole Act in Turkey would be low once Turkey mainly differs from the States regarding social, economic and cultural traits.

Keywords: Bayh-Dole act, knowledge transfer, license, patent, spin-off.

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15 Impact of Enhanced Business Models on Technology Companies in the Pandemic: A Case Study about the Revolutionary Change in Management Styles

Authors: Murat Colak, Berkay Cakir Saridogan

Abstract:

Since the dawn of modern corporations, almost every single employee has been working in the same loop, which contains three basic steps: going to work, providing the needs for the work, and getting back home. Only a small amount of people was able to break that standard and live outside the box. As the 2019 pandemic hit the Earth and most companies shut down their physical offices, that loop had to change for everyone. This means that the old management styles had to be significantly re-arranged to the "work from home" type of business methods. The methods include online conferences and meetings, time and task tracking using algorithms, globalization of the work, and, most importantly, remote working. After the global epidemic started, even the tech giants were concerned. Now, it can be seen that those technology companies have an incredible step-up in their shares compared to the other companies because they know how to manage such situations even better than every other industry. This study aims to take the old traditional management styles in big companies and compare them with the post-Covid methods (2019-2022). As a result of this comparison made using the annual reports and shared statistics, this study aims to explain why the winners of this crisis are the technology companies.

Keywords: COVID-19, technology companies, business models, remote work.

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14 Changing Human Resources Policies in Companies after the COVID-19 Pandemic

Authors: C. Murat, T. Elifnaz

Abstract:

Today, with globalization, human mobility has increased the interaction between countries significantly, and this contact has also increased the possibility of epidemics, although this contact has moved societies forward in terms of civilization. The coronavirus (COVID-19) epidemic, which caused the most loss of life from these epidemics, quickly swept the whole world with the effect of globalization. The coronavirus epidemic has affected the world economically as well as health problems. While some businesses around the world experienced an extraordinary increase in demand, some businesses temporarily stopped their activities or were forced to do so. Businesses affected by the crisis had to adapt to new legal regulations but had to make changes in matters such as working styles, human resources practices, and policies. One of the measures considered is the reduction of the workforce. The current COVID-19 crisis has created serious challenges for many organizations and has led to an unprecedented wave of termination notices. In this study, examples of companies that were affected by the pandemic process and changed their working policies after the pandemic were examined. This study aims to reveal the impact of the global COVID-19 epidemic on human resources policies and employees and how these situations will affect businesses in the future.

Keywords: COVID-19, human resource management, crisis management, business function.

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13 The Search of Anomalous Higgs Boson Couplings at the Large Hadron Electron Collider and Future Circular Electron Hadron Collider

Authors: Ilkay Turk Cakir, Murat Altinli, Zekeriya Uysal, Abdulkadir Senol, Olcay Bolukbasi Yalcinkaya, Ali Yilmaz

Abstract:

The Higgs boson was discovered by the ATLAS and CMS experimental groups in 2012 at the Large Hadron Collider (LHC). Production and decay properties of the Higgs boson, Standard Model (SM) couplings, and limits on effective scale of the Higgs boson’s couplings with other bosons are investigated at particle colliders. Deviations from SM estimates are parametrized by effective Lagrangian terms to investigate Higgs couplings. This is a model-independent method for describing the new physics. In this study, sensitivity to neutral gauge boson anomalous couplings with the Higgs boson is investigated using the parameters of the Large Hadron electron Collider (LHeC) and the Future Circular electron-hadron Collider (FCC-eh) with a model-independent approach. By using MadGraph5_aMC@NLO multi-purpose event generator with the parameters of LHeC and FCC-eh, the bounds on the anomalous Hγγ, HγZ and HZZ couplings in e− p → e− q H process are obtained. Detector simulations are also taken into account in the calculations.

Keywords: Anomalous Couplings, Effective Lagrangian, Electron-Proton Colliders, Higgs Boson.

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12 Differentiation of Cancerous Prostate tissue from Non-Cancerous Prostate tissue by using Elastic Light Single-Scattering Spectroscopy: A Feasibility Study

Authors: T. Denkçeken, M. Canpolat, Đ. Bassorgun, S. Yücel, M.A. Çiftçioğlu, M. Baykara Murat Canpolat , Tuba Denkçeken , Đbrahim Bassorgun , Selçuk Yücel , M. Akif Çiftçioğlu , Mehmet Baykara

Abstract:

Elastic light single-scattering spectroscopy system with a single optical fiber probe was employed to differentiate cancerous prostate tissue from non-cancerous prostate tissue ex-vivo just after radical prostatectomy. First, ELSSS spectra were acquired from cancerous prostate tissue to define its spectral features. Then, spectra were acquired from normal prostate tissue to define difference in spectral features between the cancerous and normal prostate tissues. Of the total 66 tissue samples were evaluated from nine patients by ELSSS system. Comparing of histopathology results and ELSSS measurements revealed that sign of the spectral slopes of cancerous prostate tissue is negative and non-cancerous tissue is positive in the wavelength range from 450 to 750 nm. Based on the correlation between histopathology results and sign of the spectral slopes, ELSSS system differentiates cancerous prostate tissue from non- cancerous with a sensitivity of 0.95 and a specificity of 0.94.

Keywords: Diagnosis, prostatic neoplasm, prostatectomy, spectrum analysis

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