Search results for: Murat Guven
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 137

Search results for: Murat Guven

107 Effects of Local Decongestive Agents at Trachea and Lungs

Authors: Sertac Arslan, Guven Guney, Ayse Ipek Akyuz Unsal, Emre Demir, Buket Demirci

Abstract:

Purpose: There is little histologic data concerning effects of nasal decongestants on the respiratory tract. We aimed to put forth the effects of nasal decongestants on the trachea and lower airways of rats. Materials and Methods: Four to six months old 60 male rats were randomly categorized into 6 groups. Experimental drugs were applied to the same nostril of rats twice daily for 8 weeks (Xylometazolin, Benzalkolyum, EDTA, Sorbitol and combined drug solutions). We applied normal saline solution (NaCl %0.9) for the control group. In the end, trachea and both lungs were dissected and kept in formaldehyde for histopathologic evaluation. Results: Inflammation and bronchial edema were most common findings. While all rats in sorbitol group had increased numbers of type 2 pneumocytes; 80% of BAC group had increased numbers of type 2 pneumocytes. Spillover of tracheal epithelium was seen mostly in sorbitol, EDTA and combined drug groups (60%, 87.5%, 50% respectively). Bronchial smooth muscle hypertrophy was seen mostly in BAC and EDTA group (70%, 62.5% respectively). The number of goblet cells showed the significant difference between control-combined drug (p=0.025) and control-BAC (p=0.001) groups. Conclusions: Nasal decongestants can cause permanent changes at lower respiratory tract in addition to changes in upper respiratory tract.

Keywords: decongestive agents, xylometazoline, lung, trachea

Procedia PDF Downloads 149
106 Kinetic Evaluation of Biodegradability of Paint Shop Wastewater of a Bus Production Factory

Authors: Didem Güven, Oytun Hanhan, Elif Ceren Aksoy, Emine Ubay Çokgör

Abstract:

This paper presents a biological treatability study ofpaintshopwastewaterof a bus factory by an anoxic/aerobic sequencing batch reactor.A lab scale 14L SBR system was implementedto investigate carbon and nitrogen removal performance frompaint shop waste streams combined with domestic and process wastewater of a bus production factory in Istanbul (Turkey).The wastewater collected from decanters of the paint boots and pre-treatmentplant was usedforthefeeding of SBR. The reactor was operated with a total hydraulic retention time of 24 hrs, and a total sludge age of 18.7 days. Initially the efficiency and stability of the reactor were studied when fed with main wastewater stream to simulate the current wastewater treatment plant. Removal efficiency of 57% nitrogen and 90% COD were obtained. Once the paint shop wastewater was introduced to mainstream feeding with a ratio of 1:5, nitrification completely, carbon removal were partially inhibited. SBR system was successful to handle even at very high COD concentrations of paint shop wastewater after feeding of 2 months, with an average effluent COD of 100 mg/L. For the determination of kinetic parameters, respirometric analysis was also conducted with/without paint shop wastewater addition. Model simulation indicated lower maximum specific growth and hydrolysis rates when paint shop wastewater was mixed with the mainstream wastewater of the factory.

Keywords: biological treatability, nitrogen removal, paint shop wastewater, sequencing batch reactor

Procedia PDF Downloads 266
105 An Improvement Study for Mattress Manufacturing Line with a Simulation Model

Authors: Murat Sarı, Emin Gundogar, Mumtaz Ipek

Abstract:

Nowadays, in a furniture sector, competition of market share (portion) and production variety and changeability enforce the firm to reengineer operations on manufacturing line to increase the productivity. In this study, spring mattress manufacturing line of the furniture manufacturing firm is analyzed analytically. It’s intended to search and find the bottlenecks of production to balance the semi-finished material flow. There are four base points required to investigate in bottleneck elimination process. These are bottlenecks of Method, Material, Machine and Man (work force) resources, respectively. Mentioned bottlenecks are investigated and varied scenarios are created for recruitment of manufacturing system. Probable near optimal alternatives are determined by system models built in Arena simulation software.

Keywords: bottleneck search, buffer stock, furniture sector, simulation

Procedia PDF Downloads 329
104 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, optimization, oil-type transformers, dry-type transformers

Procedia PDF Downloads 315
103 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 medium enterprises (SMEs), six sigma, Pakistan

Procedia PDF Downloads 312
102 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. The 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, modification, dynamic mechanical analysis

Procedia PDF Downloads 63
101 Comparison of Isokinetic Powers (Flexion and Knee Extension) of Basketball and Football Players (Age 17–20)

Authors: Ugur Senturk, Ibrahım Erdemır, Faruk Guven, Cuma Ece

Abstract:

The objective of this study is to compare flexion and extension movements in knee-joint group by measuring isokinetic knee power of amateur basketball and football players. For this purpose, total 21 players were included, which consist of football players (n=12) and basketball players (n=9), within the age range of 17–20. After receiving the age, length, body weight, vertical jump, and BMI measurements of all subjects, the measurement of lower extremity knee-joint movement (Flexion-Extension) was made with isokinetic dynamometer (isomed 2000) at 60 o/sec. and 240 o/sec. angular velocity. After arrangement and grouping of collected information forms and knee flexion and extension parameters, all data were analyzed with SPSS for Windows. Descriptive analyses of the parameters were made. Non-parametric t test and Mann-Whitney U test were used to compare the parameters of football players and basketball players and to find the inter-group differences. The comparisons and relations in the range p<0.05 and p<0.01 between the groups were surveyed. As a conclusion, no statistical differences were found between isokinetic knee flexion and extension parameters of football and basketball players. However, it was found that the football players were older than the basketball players. In addition to this, the average values of the basketball players in the highest torque and the highest torque average curve were found higher than football players in comparisons of left knee extension. However, it was found that fat levels of the basketball players were found to be higher than the football players.

Keywords: isokinetic contraction, isokinetic dynamometer, peak torque, flexion, extension, football, basketball

Procedia PDF Downloads 498
100 Buckling Analysis of Composite Shells under Compression and Torsional Loads: Numerical and Analytical Study

Authors: Güneş Aydın, Razi Kalantari Osgouei, Murat Emre Öztürk, Ahmad Partovi Meran, Ekrem Tüfekçi

Abstract:

Advanced lightweight laminated composite shells are increasingly being used in all types of modern structures, for enhancing their structural efficiency and performance. Such thin-walled structures are susceptible to buckling when subjected to various loading. This paper focuses on the buckling of cylindrical shells under axial compression and torsional loads. Effects of fiber orientation on the maximum buckling load of carbon fiber reinforced polymer (CFRP) shells are optimized. Optimum fiber angles have been calculated analytically by using MATLAB program. Numerical models have been carried out by using Finite Element Method program ABAQUS. Results from analytical and numerical analyses are also compared.

Keywords: buckling, composite, cylindrical shell, finite element, compression, torsion, MATLAB, optimization

Procedia PDF Downloads 560
99 Manufacturing Commercial Bricks with Construction and Demolition Wastes

Authors: Mustafa Kara, Yasemin Kilic, Bahattin Murat Demir, Ümit Ustaoglu, Cavit Unal

Abstract:

This paper reports utilization of different kind of construction and demolition wastes (C&D) in the production of bricks at industrial scale. Plastered brick waste and tile wastes were collected from ISTAÇ Co. Compost and Recovery Plant, Istanbul, Turkey. Plastered brick waste and tile waste are mixed with brick clay in the proportion of 0-30% and fired at 900ºC. The physical and mechanical properties of the produced bricks were determined and evaluated according to IKIZLER Brick Company Production values, Brick Industry Association (BIA) and Turkish Standards (TS). The resulted showed that plastered brick waste and tile waste can be used to produce good quality brick for various engineering applications in construction and building. The replacement of brick clay by plastered brick waste and tile waste at the levels of 30% has good effects on the compressive strength of the bricks.

Keywords: commercial brick, construction and demolition waste, manufacturing, recycling

Procedia PDF Downloads 321
98 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

Procedia PDF Downloads 558
97 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 intelligence-based (ANN based) 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 intelligence, earthquake, performance, reinforced concrete

Procedia PDF Downloads 439
96 Investigation of Heat Transfer of Nanofluids in Circular Microchannels

Authors: Bayram Sahin, Hourieh Bayramian, Emre Mandev, Murat Ceylan

Abstract:

In industrial applications, the demand for the enhancement of heat transfer is a common engineering problem. The use of additives to heat transfer fluid is a technique applied to enhance the heat transfer performance of base fluids. In this study, the thermal performance of nanofluids consisting of SiO2 particles and deionized water in circular microchannels was investigated experimentally. SiO2 nanoparticles with diameter of 15 nm were added to water to prepare nanofluids with 0.2% and 0.4% volume fractions. Heat transfer characteristics were calculated by using temperature, flow and pressure measurements. The thermal conductivity and viscosity values required for the calculations are measured separately. It is observed that the Nusselt number increases at the all volume fraction of particles, by increasing the Reynolds number and the volumetric ratios of the particles. The highest heat transfer enhancement is obtained at Re = 2160 and 0.4 % vol. by 14% under the condition of a constant pumping power.

Keywords: nanofluid, microchannel, heat transfer, SiO2-water nanofluid

Procedia PDF Downloads 357
95 Evaluating the Extent to Which Higher Education in Creativity Match with Demands of the Industry in Istanbul

Authors: Büşra Güven, Ebru Kerimoğlu

Abstract:

Relevant departments of universities in creative fields are increasingly facing the challenge of developing curriculum for more employable creative workforce. In Turkey, as a developing country, the creative industries have not yet argued in the political axis and higher education also has not been addressed in this context. Istanbul has the highest creative and cultural industries share also provides both rooted and developing higher education institutes for these sectors in Turkey. With this in mind, the main purpose of the paper attempts to clarify that how does higher education in creative fields deal with the demands of creative industries in Istanbul? First, the paper elaborated creative class theory, second creative industries, employability and curriculum triangle is examined. The research methodology consisted of a qualitative model based on interview analysis. Data are collected by interviews with the head of the relevant departments and professional associations authorities in selected sectors. Four higher education institutes in Istanbul are selected according to the some clarified factors related to the literature. This also offered a comparing between public and private universities in terms of the adaptability of this changing concept of work. Industry expectations and content of educations were compared and found the blind spots in the education-industry relationships. As a consequence, produced inclusive policies for universities and industries to overcome these spots with collaboration, flexibility, adaptability, openness and feedback management and also for future policies in particular outcomes of university-industry collaborations.

Keywords: creative industries, curriculum, employability, high education, Istanbul

Procedia PDF Downloads 205
94 The Effect of Ethylene Propylene Diene Monomer on the Rheological Properties of Bitumen

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

Abstract:

This study aimed to investigate the mechanical and high-temperature rheological properties of Ethylene Propylene Diene Monomer (EPDM) modified bitumen. To achieve this, the neat binder was modified with EPDM additive in different percentages: 2% to 5%. The neat and modified binder were subjected to conventional and rheological tests, including penetration and softening point tests, as well as evaluations of their rutting performance and high-temperature viscosity characteristics. Additionally, the mixing and compaction temperatures for hot mix asphalt production were identified using a rotational viscometer. The findings indicated that EPDM is a highly effective bitumen modifier, with the high temperature performance class of the neat binder improving by 3 grades according to the Superpave asphalt grading system.

Keywords: polymer, bitumen, rheology, EPDM, dynamic mechanical analysis

Procedia PDF Downloads 87
93 The Effect of Exercise, Reflexology and Chrome on Metabolic Syndrome

Authors: F. Arslan, S.D. Guven, A. Özcan, H. Vatansev, Ö. Taşgin

Abstract:

Weight, hypertension and dyslipidemia control and increased physical activity are required for the treatment of metabolic syndrome (METS). The purpose of this study was to investigate the effect of core exercise, reflexology and intake chrome picolinate on METS. This study comprised a twelve-week randomized controlled trial. A total of 25 university workers with metabolic risk factors participated in this study voluntarily. They were randomly divided into three groups: Those undertaking a core exercise program (n=7), reflexology intervention group (n=8) and intake chrome group (n=10). The subjects took part in a core exercise program for one hour per day, three days a week and a reflexology interfered for thirty minutes per day, one days a week and chrome group took chrome picolinate every day in week for twelve weeks. The components of metabolic syndrome were analyzed before and after the completion of all the intervention. There were significant differences at pre-prandial blood glucose in the core exercise group and at systolic blood pressure in chrome group after the twelve week interventions (p < 0.005). While High Density Lipoprotein (HDL) excluding the components of METS decreased after the interventions on the all groups; levels of HDL and the other components of METS decreased in reflexology group. There was a clear response to the twelve-week interventions in terms of METS control. Besides, the reflexology intervention should not be applied to individuals with low HDL levels and core exercise and intake chrome picolinate suggested to improve the components of METS.

Keywords: blood pressure, body mass index, exercise, METS, pre-prandial blood glucose

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92 Determination of the Inhibitory Effects of N-Methylpyrrole Derivatives on Glutathione Reductase Enzyme

Authors: Esma Kocaoglu, Oktay Talaz, Huseyin Cavdar, Murat Senturk, Deniz Eki̇nci̇

Abstract:

Glutathione reductase (GR) is a crucial antioxidant enzyme which is responsible for the maintenance of the antioxidant GSH (glutathione) molecule. Antimalarial effects of some chemical molecules are attributed to their inhibition of GR; thus inhibitors of this enzyme are expected to be promising candidates for the treatment of malaria. In this work, GR inhibitory properties of N-Methylpyrrole derivatives are reported. Firstly, GR was purified by means of affinity chromatography using 2’,5’-ADP-Sepharose 4B as ligand. Enzymatic activity was measured by Beutler’s method. Synthesis of the compounds was approved by thin layer chromatography and column chromatography. Different inhibitor concentrations were used and all compounds were tested in triplicate at each concentration used. It was found that all compounds have better inhibitory activity than the strong GR inhibitor N,N-bis(2-chloroethyl)-N-nitrosourea, especially three molecules, 8m, 8n, and 8q, are the best among them with low micromolar I₅₀ values. Findings of our study indicate that these Schiff base derivatives are strong GR inhibitors which can be used as leads for designation of novel antimalaria candidates.

Keywords: glutathione reductase, antimalaria, inhibitor, enzyme

Procedia PDF Downloads 243
91 Effects of the Different Recovery Durations on Some Physiological Parameters during 3 X 3 Small-Sided Games in Soccer

Authors: Samet Aktaş, Nurtekin Erkmen, Faruk Guven, Halil Taskin

Abstract:

This study aimed to determine the effects of 3 versus 3 small-sided games (SSG) with different recovery times on soma physiological parameters in soccer players. Twelve soccer players from Regional Amateur League volunteered for this study (mean±SD age, 20.50±2.43 years; height, 177.73±4.13 cm; weight, 70.83±8.38 kg). Subjects were performing soccer training for five days per week. The protocol of the study was approved by the local ethic committee in School of Physical Education and Sport, Selcuk University. The subjects were divided into teams with 3 players according to Yo-Yo Intermittent Recovery Test. The field dimension was 26 m wide and 34 m in length. Subjects performed two times in a random order a series of 3 bouts of 3-a-side SSGs with 3 min and 5 min recovery durations. In SSGs, each set were performed with 6 min duration. The percent of maximal heart rate (% HRmax), blood lactate concentration (LA) and Rated Perceived Exertion (RPE) scale points were collected before the SSGs and at the end of each set. Data were analyzed by analysis of variance (ANOVA) with repeated measures. Significant differences were found between %HRmax in before SSG and 1st set, 2nd set, and 3rd set in both SSG with 3 min recovery duration and SSG with 5 min recovery duration (p<0.05). Means of %HRmax in SSG with 3 min recovery duration at both 1st and 2nd sets were significantly higher than SSG with 5 min recovery duration (p<0.05). No significant difference was found between sets of either SSGs in terms of LA (p>0.05). LA in SSG with 3 min recovery duration was higher than SSG with 5 min recovery duration at 2nd sets (p<0.05). RPE in soccer players was not different between SSGs (p>0.05).In conclusion, this study demonstrates that exercise intensity in SSG with 3 min recovery durations is higher than SSG with 5 min recovery durations.

Keywords: small-sided games, soccer, heart rate, lactate

Procedia PDF Downloads 432
90 The Determination of Stress Experienced by Nursing Undergraduate Students during Their Education

Authors: Gülden Küçükakça, Şefika Dilek Güven, Rahşan Kolutek, Seçil Taylan

Abstract:

Objective: Nursing students face with stress factors affecting academic performance and quality of life as from first moments of their educational life. Stress causes health problems in students such as physical, psycho-social, and behavioral disorders and might damage formation of professional identity by decreasing efficiency of education. In addition to determination of stress experienced by nursing students during their education, it was aimed to help review theoretical and clinical education settings for bringing stress of nursing students into positive level and to raise awareness of educators concerning their own professional behaviors. Methods: The study was conducted with 315 students studying at nursing department of Semra and Vefa Küçük Health High School, Nevşehir Hacı Bektaş Veli University in the academic year of 2015-2016 and agreed to participate in the study. “Personal Information Form” prepared by the researchers upon the literature review and “Nursing Education Stress Scale (NESS)” were used in this study. Data were assessed with analysis of variance and correlation analysis. Results: Mean NESS Scale score of the nursing students was estimated to be 66.46±16.08 points. Conclusions: As a result of this study, stress level experienced by nursing undergraduate students during their education was determined to be high. In accordance with this result, it can be recommended to determine sources of stress experienced by nursing undergraduate students during their education and to develop approaches to eliminate these stress sources.

Keywords: stress, nursing education, nursing student, nursing education stress

Procedia PDF Downloads 440
89 Effects of Heat Treatment on the Elastic Constants of Cedar Wood

Authors: Tugba Yilmaz Aydin, Ergun Guntekin, Murat Aydin

Abstract:

Effects of heat treatment on the elastic constants of cedar wood (Cedrus libani) were investigated. Specimens were exposed to heat under atmospheric pressure at four different temperatures (120, 150, 180, 210 °C) and three different time levels (2, 5, 8 hours). Three Young’s modulus (EL, ER, ET) and six Poisson ratios (μLR, μLT, μRL, μRT, μTL, μTR) were determined from compression test using bi-axial extensometer at constant moisture content (12 %). Three shear modulus were determined using ultrasound. Six shear wave velocities propagating along the principal axes of anisotropy were measured using EPOCH 650 ultrasonic flaw detector with 1 MHz transverse transducers. The properties of the samples tested were significantly affected by heat treatment by different degree. As a result, softer treatments yielded some amount of increase in Young modulus and shear modulus values, but increase of time and temperature resulted in significant decrease for both values. Poisson ratios seemed insensitive to heat treatment.

Keywords: cedar wood, elastic constants, heat treatment, ultrasound

Procedia PDF Downloads 352
88 The Effect of Substrate Surface Roughness for Hot Dip Aluminizing of IN718 Alloy

Authors: Aptullah Karakas, Murat Baydogan

Abstract:

The hot dip aluminizing (HDA) process involves immersing a metallic substrate into a molten aluminum bath for several minutes, and removed from the bath and cooled down to room temperature. After the HDA process, various aluminide layers are formed as a result of interdiffusion between the substrate and the molten aluminum and between the aluminide layers. In order to form a uniform aluminide layer, the specimen must be covered and wet well by the molten aluminum. Surface roughness plays an important role in wettability, and thus, surface preparation is an important stage in determining the final surface roughness. In this study, different roughness values were achieved by grinding the surface with emery papers as 180, 320 and 600 grids. After the surface preparation, the HDA process was performed in a molten Al-Si bath at 700 ᴼC for 10 minutes. After the HDA process, a microstructural examination of the coating was carried out to evaluate the uniformity of the coating and adhesion between the substrate and the coating. According to the results, the best adhesion at the interface was observed on the specimen, which was prepared by 320 grid emery paper having a mean surface roughness (Ra) of 0.097 µm.

Keywords: hot-dip aluminizing, microstructure, surface roughness, coating

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87 Aeroacoustics Investigations of Unsteady 3D Airfoil for Different Angle Using Computational Fluid Dynamics Software

Authors: Haydar Kepekçi, Baha Zafer, Hasan Rıza Güven

Abstract:

Noise disturbance is one of the major factors considered in the fast development of aircraft technology. This paper reviews the flow field, which is examined on the 2D NACA0015 and 3D NACA0012 blade profile using SST k-ω turbulence model to compute the unsteady flow field. We inserted the time-dependent flow area variables in Ffowcs-Williams and Hawkings (FW-H) equations as an input and Sound Pressure Level (SPL) values will be computed for different angles of attack (AoA) from the microphone which is positioned in the computational domain to investigate effect of augmentation of unsteady 2D and 3D airfoil region noise level. The computed results will be compared with experimental data which are available in the open literature. As results; one of the calculated Cp is slightly lower than the experimental value. This difference could be due to the higher Reynolds number of the experimental data. The ANSYS Fluent software was used in this study. Fluent includes well-validated physical modeling capabilities to deliver fast, accurate results across the widest range of CFD and multiphysics applications. This paper includes a study which is on external flow over an airfoil. The case of 2D NACA0015 has approximately 7 million elements and solves compressible fluid flow with heat transfer using the SST turbulence model. The other case of 3D NACA0012 has approximately 3 million elements.

Keywords: 3D blade profile, noise disturbance, aeroacoustics, Ffowcs-Williams and Hawkings (FW-H) equations, k-ω-SST turbulence model

Procedia PDF Downloads 180
86 Modeling of Cold Tube Drawing with a Fixed Plug by Finite Element Method and Determination of Optimum Drawing Parameters

Authors: E. Yarar, E. A. Guven, S. Karabay

Abstract:

In this study, a comprehensive simulation was made for the cold tube drawing with fixed plug. The cold tube drawing process is preferred due to its high surface quality and the high mechanical properties. In drawing processes applied to materials with low plastic deformability, cracks can occur on the surfaces and the process efficiency decreases. The aim of the work is to investigate the effects of different drawing parameters on drawing forces and stresses. In the simulations, optimum conditions were investigated for four different materials, Ti64Al4V, AA5052, AISI4140, and C365. One of the most important parameters for the cold drawing process is the die angle. Three dies were designed for the analysis with semi die angles of 5°, 10°, and 15°. Three different parameters were used for the friction coefficient between die and the material. In the simulations, reduction of area and the drawing speed is kept constant. Drawing is done in one pass. According to the simulation results, the highest drawing forces were obtained in Ti64Al4V. As the semi die angle increases, the drawing forces decrease. The change in semi die angle was most effective on Ti64Al4V. Increasing the coefficient of friction is another effect that increases the drawing forces. The increase in the friction coefficient has also increased in drawing stresses. The increase in die angle also increased the drawing stress distribution for the other three materials outside C365. According to the results of the analysis, it is found that the designed drawing die is suitable for drawing. The lowest drawing stress distribution and drawing forces were obtained for AA5052. Drawing die parameters have a direct effect on the results. In addition, lubricants used for drawing have a significant effect on drawing forces.

Keywords: cold tube drawing, drawing force, drawing stress, semi die angle

Procedia PDF Downloads 140
85 The Investigation of Counselors Attitudes toward Online Counseling upon Taking Clients Perspective

Authors: Omer Ozer, Murat Yikilmaz, Ahmet Altinok, Ferhat Bayolu

Abstract:

There is an increasing number of online counseling services, studies exploring clients’ and counselors’ attitudes toward online counseling services are needed to provide effective and efficient mental health counseling services. The purpose of this study is to investigate counselors’ attitudes toward online counseling in relation to counselors’ genders, their daily usage of computer, their total usage of computer, and their self-efficacy in computer usage. In this study, Personal Information Form, specific items from the Online Counseling Attitudes Scale, and the Face-to-Face Counseling Attitudes Scale were given to 193 counselors to measure attitudes toward online counseling. Data were analyzed by using independent samples t-test and one-way ANOVA. There were no statistically significant differences counselors’ attitudes toward online counseling and counselors’ gender, their daily usage of computer, their total usage of computer, and their self-efficacy in computer usage. The implications of these findings have been discussed in the literature review to provide some suggestions to researchers in the counseling profession.

Keywords: online counseling, counselor, attitude, counseling service

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84 Design and Synthesis of Some Oxadiazole Bearing Benzimidazole Derivatives as Potential Epidermal Growth Factor Receptor Inhibitors

Authors: Ismail Celik, Gulgun Ayhan Kilcigil, Berna Guven, Zumra Kara, Arzu Onay-Besikci

Abstract:

Epidermal Growth Factor Receptor is the cell-surface receptor of the ErbB (erythroblastic leukemia viral oncogene homologue receptors) family of tyrosine kinases. It plays a vital role in regulating the proliferation and differentiation of cells. However, a variety of mechanisms, such as EGFR expression, mutation, and ligand-dependent receptor dimerization, are associated with the development of various activated EGFR tumors. EGFR is highly expressed in most solid tumors, including breast, head and neck cancer, non-small cell lung cancer (NSCLC), renal, ovarian, and colon cancers. Thus, specific EGFR inhibition plays one of the key roles in cancer treatment. The compounds used in the treatment as tyrosine kinase inhibitors are known to contain the benzimidazole isosterium indole, pazopanib, and axitinibin indazole rings. In addition, benzimidazoles have been shown to exhibit protein kinase inhibitory activity in addition to their different biological activities.Based on these data, it was planned and synthesized of some oxadiazole bearing benzimidazole derivatives [N-cyclohexyl-5-((2-phenyl/substitutedphenyl-1H-benzo[d]imidazole-1-yl) methyl)-1,3,4-oxadiazole-2-amine]. EGFR kinase inhibitory efficiency of the synthesized compounds was determined by comparing them with a known kinase inhibitor erlotinib in vitro, and two of the compounds bearing phenyl (19a) and 3,4-dibenzyloxyphenyl (21a) ring exhibited significant activities.

Keywords: benzimidazole, EGFR kinase inhibitory, oxadiazole, synthesis

Procedia PDF Downloads 109
83 Estimating the Properties of Polymer Concrete Using the Response Surface Method

Authors: Oguz Ugurkan Akkaya, Alpaslan Sipahi, Ozgur Firat Pamukcu, Murat Yasar, Tolga Guler, Arif Ulu, Ferit Cakir

Abstract:

With the increase in human population, expansion, and renovation of cities, infrastructure systems today need to be manufactured to be more durable and long-lasting. The most cost-effective and durable manufacturing of components is a general problem of all engineering disciplines. Therefore, it is important to determine the most optimal components. This study mainly focuses on the most optimal component design of the polymer concrete. For this purpose, the lower and upper limits of the three main components of the polymer concrete are determined. The effects of these three principal components on the compressive strength, tensile strength, and unit price of polymer concrete are estimated using the response surface method. Box-Behnken Design is used in designing the experiments. Compressive strength, tensile strength, and unit prices are successfully estimated with variance ratios (R²) of 0.82, 0.92, and 0.90, respectively, and the optimum mixture quantity is determined.

Keywords: Box-Behnken Design, compressive strength, mechanical tests, polymer concrete, tensile strength

Procedia PDF Downloads 141
82 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

Procedia PDF Downloads 236
81 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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80 Effects of Li2O Doping on Mechanical and Electrical Properties of Bovine Hydroxyapatite Composites (BHA)

Authors: Sibel Daglilar, Isil Kerti, Murat Karagoz, Fatih Dumludag, Oguzhan Gunduz, Faik Nuzhet Oktar

Abstract:

Hydroxyapatite (HA) materials have common use in bone repairing due to its ability to accelerate the bone growth around the implant. In spite of being a biocompatible and bioactive material, HA has a limited usage as an implant material because of its weak mechanical properties. HA based composites are required to improve the strength and toughness properties of the implant materials without compromising of biocompatibility. The excellent mechanical properties and higher biocompatibilities are expected from each of biomedical composites. In this study, HA composites were synthesized by using bovine bone reinforced doped with different amount of (wt.%) Li2O. The pressed pellets were sintered at various sintering temperatures between 1000ºC and 1300°C, and mechanical, electrical properties of the obtained products were characterized. In addition to that, in vitro stimulated body fluid (SBF) tests for these samples were conducted. The most suitable composite composition for biomedical applications was discussed among the composites studied.

Keywords: biocomposites, sintering temperature, biocompatibility, electrical property, conductivity, mechanical property

Procedia PDF Downloads 373
79 Investigation of Maxi̇mali̇st Approaches on Furni̇ture Desi̇gn

Authors: Emi̇ne Yuksel, Murat Kiliç, Onur Ülker

Abstract:

Although minimalism has been coming into being in the field of interior design for a long time, it also brought a wide range of reaction. The more simple and feeling of emptiness usage of minimalism in space and furniture design has been found extremely boring so far, as a reaction to minimalism, a movement of maximalism was emerged. Thus more extravagant, splendid, magnificent and comfortable design approach was substituted by the greatest, largest and the extreme. Thus, the philosophy of “less is bore” of minimalism was replaced by “less is more” giving rise to a new interpretation in the field of interior design. While maximalism reminded us the Victorian, Rococo, Arts and Crafts and Neoclassic styles in interior design, it drew attention to the furniture designs that covered all areas of space all in one. In this study, we search the effect of maximalist approach which was born as a reaction to minimalism in furniture. Firstly, it is explained how did the maximalism emerge and its philosophy, a literature investigation was scanned and investigated. As a research method, it is concerned with the investigation of studies undertaken by the pioneers of interior space designers and architects. The findings of this study have been evaluated in the conclusion section.

Keywords: furniture design, maximalism, minimalism, texture

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

Authors: Murat Çolak, Elifnaz Tanyıldızı

Abstract:

Today, human mobility with globalization has increased the interaction between countries significantly; although this contact has advanced societies in terms of civilization, it has also increased the likelihood of pandemics. The coronavirus (COVID-19) pandemic, which caused the most loss of life among them, turned into a global epidemic by covering the whole world in a short time. While there was an explosion in demand in some businesses around the world, some businesses temporarily stopped or had to stop their activities. The businesses affected by the crisis had to adapt to the new legal regulations but had to make changes in matters such as their working styles, human resources practices, and policies. One of the measures taken into account is the reduction of the workforce. The current COVID-19 crisis has posed serious challenges for many organizations and has generated an unprecedented wave of termination notices. This study examined examples of companies affected by the pandemic process and changed their working policies after the pandemic. This study aims to reveal the impact of the global COVID-19 pandemic on human resources policies and employees and how these situations will affect businesses in the future.

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

Procedia PDF Downloads 67