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The usage of screw piles is one of the increasingly widespread ground improvement methods. In this study, the behaviour of linear, triangular, and square pattern screw piles in groups under tensile and compressive forces is investigated. The model experiments in the literature on screw piles were modelled by finite element method and a reasonably accurate agreement with the experimental results was obtained. Then, the number of helixes and helix diameters of the screw piles used in the experimental study were changed and the effect of the change in the number of helixes and diameter on the bearing capacity was investigated. Also, the behaviour and failure surfaces of screw piles under load were investigated. In conclusion, increasing the number of helixes significantly increased the bearing capacity. In fact, it was observed that the increase in the number of helixes was sufficient to reduce the number of piles as a result of the increase in the bearing capacity up to 100%. In addition, the increasing the diameter of the helixes by 1.8 times resulted an increase in the bearing capacity values between 80% and 100%. However, it was determined that the bearing capacity increases were different in each pattern. [ABSTRACT FROM AUTHOR]

In this study, the free vibration analysis of syntactic foam curved beams with two simply supported ends was numerically investigated by the Differential Quadrature Method (DQM). The displacement field was expressed according to classical beam theory, and motion equations were derived by Newton's laws of motion. For this purpose, a DQM code was developed using MATLAB, and the natural frequencies of structures were obtained to examine the effects of material parameters such as microballoon (MB) volume fractions, MB densities, as well as geometric parameters like curvature angle and curvature radius on the free vibration analysis of epoxy/glass microballoon-based syntactic foam curved beams. The results obtained from the research indicate that MB volume fractions, densities, and the geometric characteristics of curved beams significantly influence the vibration behavior of syntactic foam curved beams. [ABSTRACT FROM AUTHOR]

This article assesses specific components of the agricultural sector as it impacts the growth of a developing nation’s economy. A mathematical model is developed with the aid of logistic growth model for the variables and the resulting model is solved numerically using a higher derivative block method to forecast the data for the agricultural components for years 2020- 2025, thus utilizing data ranging from 1981-2025. Econometric analysis was carried out using ARDL bound test method and the findings indicate the existence of short and long run relationship between food production, livestock, and economic growth. In addition, the Pairwise Granger causality showed the causality movement and ascertain the positive link among the variables. Therefore, this research suggests the need to encourage food production and livestock as components of agriculture through precise economic policies and funding for progress in the country’s economic outlook.

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Firat University Journal of Experimental & Computational Engineering (FUJECE) is the property of Firat University Journal of Experimental & Computational Engineering (FUJECE) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bu çalışmada, Amerikan Karayolları Müdürlüğü FHWA (Federal Highway Administration) tarafından geliştirilmiş bir yazılım olan DRIP (Drenage Requirement in Pavements) aracılığıyla, demir çelik endüstrisi atık malzemesi olarak ortaya çıkan çelik cüruflarının hidrolik iletkenliğinin drenaj süresi ve karayolu temel tabakasının kalınlığı üzerindeki etkisi incelenmiştir. Analizlerde üçü elektrik ark fırını (EAF), bir tanesi pota fırını (PF) cürufu olmak üzere dört farklı tesisten elde edilmiş çelik cürufu (SS), ayrıca drenaj performansının karşılaştırması ve kontrol amacıyla bir adet tabii zemin malzemesi kullanılmıştır. Drenaj yüzdesi (U), temel tabakası kalınlığı (H) ve hidrolik iletkenlik (k)’in drenaj süresi üzerindeki etkisi incelenmiş olup analizler sonucunda ince dane içeriğinin ve hidrolik iletkenliğin, özellikle drenaj süresini, drenajın %40’ı tamamlandıktan sonra önemli ölçüde etkilediği görülmüştür. Ayrıca, temel kalınlığının arttırılması, drenaj süresinde ciddi bir azalmaya neden olmaktadır. Kontrol malzemesi ile farklı tesislerden elde edilmiş çelik cürufu malzemesinin performansları karşılaştırıldığında, özellikle elektrik ark fırını çelik cürufu malzemelerinin drenaj özelliklerinin yol dolgusu malzemesi olarak kullanımında tatmin edici sonuçlar verdiği gözlemlenmiştir.

Copyright of Selcuk University Social Sciences Institute Journal is the property of Selcuk University Social Sciences Institute Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the effect of hydraulic conductivity of steel slag, a by-product of steel industry, on the drainage time and the thickness of the highway foundation layer was investigated via DRIP (Drainage Requirement in Pavements) software developed by Federal Highway Administration (FHWA). Three electric arc furnace (EAF) and one ladle slag (LS) from four different facilities along with a control soil were used in the analyses to compare their drainage performance as an embankment material. Analyzes were performed on steel slag and natural aggregate materials to investigate the effect of drainage percentage (U), base layer thickness (H) and hydraulic conductivity (k) on drainage time. The results show that the fines content and hydraulic conductivity significantly affect the drainage time, especially after 40% of the drainage. In addition, increasing the thickness of the foundation causes a serious reduction in the drainage time. When the performances of the control material and the steel slag obtained from different facilities were compared, it was seen that the drainage properties of especially the electric arc furnace steel slag materials yielded satisfactory results in case used as an embankment fill material [ABSTRACT FROM AUTHOR]

This study aimed to reveal predictions about how the total pressure difference occurring in front of and behind the radiator in the cabin generator set affects the operating temperature of the generator set in the absence of sufficient thermal information. After the cabin design, numerical analyses were made for three louvers with different depth dimensions, as that they significantly affect the total pressure difference. It was found the most suitable louver depth as a result of numerical analysis. Flow analyses were created by using ANSYS FLUENT 19.2 software as a numerical study of the generator cabin. Numerical analyses haven't been created based on temperature since thermal information was not adequately available. As a result of numerical studies, a total pressure difference of 139.25 Pa has occurred. This pressure difference value is 14.25 Pa higher than the pressure difference value allowed by the radiator of the 1104C-44TAG2 engine. Firstly, the generator set was manufactured. Then it was implemented experimental studies with the HIOKI test device to determine how the pressure difference value of 14.25 Pa affects the temperature of the generator set. The result shows that the pressure difference of 14.25 Pa reduces the maximum ambient temperature at which the generator can operate by 3.9°C as a result of the experimental studies [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the sensitivity levels and contribution rates of the performance parameters that have an effect on the Organic Rankine Cycle (ORC) were determined. Performance parameters were chosen as evaporator-condenser pinch point temperature difference (ΔTPP,e, ΔTPP,k), cooling water inlet temperature (Tc,i), superheating temperature (Tak), turbine-pump isentropic efficiencies (ηt ve ηp). The effects of these parameters on the ORC system were evaluated under different objective functions. Examined objective functions; thermal efficiency, net power, and exergy efficiency maximization; total irreversibility, volumetric flow rate (VFR) and environmental impact factor (EEF) minimization. Thus, thermodynamic performance with energy-exergy analysis; VFR, which has a significant impact on turbine economy; thermodynamic sustainability indices and environmental factor were examined. It has been determined that the effect of performance parameters varies greatly with the change of objective functions. While the effect of ΔTPP,e was 20.59% effective in obtaining maximum thermal efficiency, it was determined that it was 71.9% effective in obtaining maximum turbine power. Taguchi-ANOVA was used in the study. By using the L25 orthogonal array, the optimum orthogonal arrays and the sensitivity level order of the parameters have been determined to reach the objective functions. By defining a weight function that affects all objective functions equally, it was determined that 42.85% ΔTPP,e and 25.71% Tc,i had an effect on ORC performance. Finally; with regression analysis, equations are derived for each objective function depending on the performance parameters. The error rates between the results estimated by the empirical equation and the numerical analysis results were extracted. Considering these ratios, it has been determined that empirical equations can be used successfully in determining ORC performance. [ABSTRACT FROM AUTHOR]

Copyright of lnternational Journal of Geography & Geography Education is the property of Marmara University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the friction and damping values that arise during the deployment of the folded fin mechanism were obtained according to the experimental data. Although there are recommended values for friction in the literature, damping is a phenomenon that varies from system to system and must be obtained through test data. In this study, firstly, the mechanism was operated on the test device with a specific enclosed volume drive pressure and the actual drive pressure generated in the system was measured. The dynamic behavior of the mechanism was recorded by a High-Speed camera system as well. Adams MBD (multi body dynamics) was used to define the mechanism model and drive pressure data from the test was defined as input to the model. With the help of Adams DOE (design of experiments), certain intervals were defined for friction and damping values. Multiple analyses were carried out at the defined friction and damping intervals and total deployment time of the mechanism and the dynamic behaviors that mechanism exhibited during deployment were obtained. Friction and damping values were obtained from the numerical results which have the highest correlation with the Test-C. The same mechanism was tested for different drive pressures with the specified friction and damping values and the test results were compared with the numerical models. Finally it was decided that the friction and damping values determined with this working method could be used in future numerical analyses of gas powered mechanisms. [ABSTRACT FROM AUTHOR]

Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study presents the investigation of the cutting force and chip formation process in hot machining of Monel K-500 alloy via finite element analysis. ThirdWave AdvantEdge software has been utilized for finite element analysis. For numerical analysis, cutting speed of 300 m/min, feed rate of 0.1 mm/rev, and 1 mm depth of cut have been selected as cutting parameters. Cutting simulations have been performed at room temperature (24°C) and four different heating temperatures (150°C, 300°C, 450°C, and 600°C) to determine the effect of hot processing. According to the results of the numerical analysis, it was observed that the cutting forces decreased in hot machining conditions compared to room temperature conditions, and the chip formed in the form of segmented chips in room temperature conditions, while it was formed as continuous type chips in hot machining conditions. The lowest cutting force value was measured as 315 N in numerical analyzes performed at 300 m/min cutting speed, 0.1 mm/rev feed rate, 1 mm depth of cut, and 600°C hot machining conditions. Moreover, it was determined that the cutting force decreased by approximately 34.14% at this heating temperature compared to the dry cutting condition. [ABSTRACT FROM AUTHOR]

One of the most important factors that increase the destructive effects of earthquakes and structural damages is the soil deformations during strong ground motion. The liquefaction occurs especially in saturated sandy soils as a result of the sudden increase in pore water pressure during the earthquakes and leads to large deformations in the soil layer and serious damages to engineering structures. In this study, by using three different sand properties with relative densities of 35, 55 and 75%, two-dimensional soil profiles were created and dynamic analyzes were carried out using fourteen different acceleration-time histories records. In the numerical analysis was performed with a finite element software and PM4Sand constitutive equations were used to model the liquefaction behavior of sand layers. The numerical analysis results were compared with the well-known semi-empirical methods in the literature. In addition, the relationships between the parameters used to define strong ground motion and the liquefaction-induced settlements obtained from numerical and semi-empirical analyzes were investigated. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to investigate the effects of central ventilation system hood design on capture performance. Commercial computational fluid dynamic (CFD) software was used to optimize the hood design and predict capture performance. Thanks to the CFD software, the hood with real dimensions was modeled and numerical analyzes were carried out. In numerical analysis, the turbulent flow in the hood was prevented by the air guide attached to the hood. In this way, an increase was achieved in the hood capture velocity and airflow rate. With the information obtained as a result of CFD analysis, hood prototypes were created and real environment experiments were carried out. Numerical analysis performed at different flow rates were confirmed by experimental analyzes. As a result, CFD analysis showed that the air guide added to the hood prevents turbulence in the air flow and increases the hood performance. [ABSTRACT FROM AUTHOR]

This study focuses on the fractional version of the FitzHugh-Nagumo (FHN) neuron model. Firstly, the stability analysis of the fractionalorder FHN neuron model has been performed and the minimum fractional degree, at which the system could exhibit dynamic behavior, has been determined. Then, the responses of the fractional-order FHN neuron model have been obtained using the Grünwald-Letnikov (G-L) fractional derivative method. This method is one of the methods used in the numerical analysis of the systems that are represented by fractional order. Thanks to the hardware solutions of neuron models; the responses of mathematically defined systems can be obtained in the form of real-time signals, the cell membrane properties of the neurons can be described electromechanically, and the parameters that affect the dynamic behavior of neurons can be associated with the characteristics of the electronic components used in hardware solutions. In this study, the circuit implementation of the fractionalorder FHN neuron model is emphasized in order to see the usability of fractional-order calculations in systems that are inspired by biology. In this context, the R-C mimetic circuits have been used instead of classical capacitor elements to compensate for the fractional order in the integrator circuits that are designed by using op-amp, resistor and capacitor elements for the hardware solutions of the differential equations. In the first stage of the design of these R-C imitation circuits, a third-order transfer function has been obtained by the Matsuda approximation method. This obtained transfer function has been transformed into FOSTER-I R-C network and it has been used instead of the classical capacitor element in the integrator blocks of the circuit that is designed by us for the circuit implementation solution of the integer-order FHN neuron model. Thus, an alternative approach for circuit solution of the fractional-order FHN neuron model has been introduced and the verification of this structure has been made by the SPICE circuit simulation. [ABSTRACT FROM AUTHOR]

The spillways, which are the most important hydraulic elements of the dams, are designed in many different types according to the dam type and flow rates. One of the most important issues to be considered when designing spillways is the design of the aerators. In this study, the cavitational damage on the concrete surface of spillways and the effects of aerators on the cavitation wer investigated. For this purpose, a three-dimensional numerical model of a selected spillway model was prepared and Computational Fluid Dynamics (CFD) analyzes were performed in different Froude numbers. Later, a different type of aerator called as the bottom-inlet aerator was placed in the model and CFD analyzes were performed similar to the original aerators. The results obtained from the CFD analysis were compared with each other and it was concluded that both aerators were sufficiently protected from cavitation damage. The results obtained were also compared with the aerator results obtained with different types and methods in the literature. [ABSTRACT FROM AUTHOR]

The amount of energy obtained from wind turbines is increasing day by day. One of the factors affecting the power output of wind turbines is blade profiles. In this study, simulations of different blade profiles (NACA 0009, NACA 2415, NACA 4415, NACA 4424, NACA 6412, NACA 6415, NACA 24112, FX 63-137, GOE 795, NREL’s S824, SD 5060, SG6040) using Qblade software created, numerically analyzed and their aerodynamic performances were examined. Numerical analyzes were performed at angle of attack between 0°and 20° and Reynolds numbers of 5x104, 2x105, 1x106 . Blade profiles with the highest aerodynamic efficiency were determined as NACA 6412, NACA 6415 and NACA 4415, and the power outputs and performance values obtained by creating a three-bladed wind turbine from these blade profiles were found. Maximum efficiency was obtained for these blade profiles in the tip-speed ratio range of 6.5 to 7.8. As a result, the efficiency to be obtained from the turbine will be at the optimum level by using NACA 6412, NACA 6415 and NACA 4415 blade profiles in wind turbines. In this study, AG37, AH 80-140, NACA 8824 and RG-12 blade profiles, which are not available in the literature, were analyzed in order to contribute to the literature. [ABSTRACT FROM AUTHOR]

Copyright of GRID - Architecture, Planning & Design Journal is the property of GRID - Architecture, Planning & Design Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Today, one of the risks that is faced by the businesses is the frauds made by employees or other people. The tricks made by these people cause a large amount of material and moral damages in the businesses, although they have negatively affect the value, the future and the profitability of the businesses, but may sometimes lead the businesses to bankruptcy as well. Fraudulent transactions made by malicious people cannot be revealed due to inadequate fraud prevention procedures or insufficient internal control. Many audit methods are currently used to reveal these tricks that occur in businesses. One of these controlling methods utilised is the Benford Law. The purpose of the study is to reveal fraudulent transactions occurring in accounting data with Benford Law, which is one of the analytical methods of analysis, and to show how they can be applied to accounting data. In line with this purpose, in order to reveal the errors and frauds that may occur in the records of the purchase invoices of an enterprise operating in the marble sector and to determine the predicted level of fraud, the first, second, first two steps and duplicate amounts tests are applied to the data of the enterprise. In order to compare the differences between the rates observed as a result of the numerical analysis tests and the rates of the Benford Law, chi-square compatibility test is performed. As a result of the numerical analysis and chi-square suitability tests, it is concluded that there has been no errors or frauds in the data of the enterprise and the amounts that cause deviation are caused by the natural structure of the company itself. [ABSTRACT FROM AUTHOR]

In this study, multi-scroll attractor generation by incorporating nonlinear trigonometric functions into the Sprott G system, which represents hyperchaotic behavior with fractional-order structure, is presented. First, the computer simulation of the original dynamic structure of the Sprott G system and the Lyapunov exponents are calculated. Then the dynamic system is reconstructed with fractional analysis methods to produce hyperchaotic attractors. A simulation study and numerical analysis of the hyperchaotic structure were made. Finally, nonlinear trigonometric function series are added to the fractional hyperchaotic system to create multi-scroll attractor structures. The computer simulation phase space representation of the dynamic behavior of the proposed system and the analysis of Lyapunov [ABSTRACT FROM AUTHOR]

Copyright of Turkish Journal of Religious Education Studies / Türkiye Din Eğitimi Araştırmaları Dergisi is the property of Turkish Journal of Religious Education Studies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Centrifugal pumps are widely used products in engineering field. It contains many different parameters according to the usage areas. At the design stage, many design parameters must be created for different flow rates and pump heads. According to the development of technology, the use of computer aided programs in the design process has become widespread. In this way, time is saved and cost is reduced. Computational Fluid Dynamics (HAD) or CFD analysis, as we are used to in a foreign language, is quite widely used in pump design. After product design and solid model generation, numerical analysis in the pump can be performed using analysis programs. The most important advantage over experimental methods is that the parameters can be changed in an unlimited number. The process can be continued until the desired values are obtained. In the light of the information obtained with the help of a computer, production and use processes can be switched. In this study, a sample centrifugal pump is considered and the numerical analysis steps are explained respectively. The methods and admissions used in the program are considered according to general literature knowledge. The methods to be applied are unlimited and solution networks can be expanded by different ways if wanted. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Defense Sciences / Savunma Bilmleri Dergisi is the property of Turkish Military Academy Defense Sciences Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Slopes can be defined in two different ways as natural slopes or constructed slopes. Just because the slopes are natural or constructed does not always mean that they can be stable. As a result of exceeding the shear strength of the ground, instability of a slope occurs. The force causing this instability is determined and compared in terms of the shear stresses occurring along the movement surface and the shear strength parameters of the soil. Today, in parallel with technological developments, software has been developed that carry out slope stability analysis using numerical analysis and limit equilibrium methods. In this study, slope stability analyzes have been performed using the Slide v.06 software based on limit equilibrium method. The reason of a mass movement in Van province was determined with the aid of back analysis. Additional analyzes were carried out and the stability of the slope was examined for both dynamic and static conditions. In the light of the results obtained from the stability analyses, a reinforced concrete retaining wall has been suggested for slope stability durability. Reinforced concrete retaining wall geometry was modelled in the software and analyzes were made by using its technical specifications as input parameters. As a result of these constituted models, the slope is stable under dynamic conditions with the aid of the proposed retaining wall. [ABSTRACT FROM AUTHOR]

Bu çalışmada, tam ve düz yarı dairesel olmak üzere iki farklı nemli nesne geometrisinin hava jeti ile kurutulmasının ısı transferi artışı ve nem miktarındaki azalışı üzerindeki etkisi sayısal olarak incelenmiştir. Jet kurutması, nemli nesneden sabit bir jet uzaklığında konumlandırılmış, laminer ve iki boyutludur. Tüm durumlarda, nemli nesnenin çapı, nemli nesneden olan jet uzaklığı ve jet giriş yüksekliği sabit alınmıştır. Farklı jet hızları için nesnelerin etrafındaki akım çizgileri ve eş sıcaklık eğrileri görselleştirilmiştir. Korunum denklemlerini çözmek için sonlu hacim yöntemi olan ANSYS Fluent 17.0 bilgisayar programı kullanılmıştır. Hesaplamalar, Re=100, 200 ve 300 olarak farklı Reynolds sayıları için gerçekleştirilmiştir. Çalışmanın, literatürde var olan sayısal ve deneysel çalışmayla iyi bir uyum içinde olduğu bulunmuştur. Sonuçlar, tam dairesel nemli nesnenin düz yarı dairesel nemli nesneden daha iyi ısı ve nem transferi performansına sahip olduğunu göstermiştir. Ayrıca, Reynolds sayısının artışının ısı ve nem transferi üzerinde olumlu bir etkiye sahip olduğu görülmüştür. Yerel olarak, jet kurutmanın nesnelerin ön taraflarındaki durma noktasına yakın daha etkili oldukları bulunmuştur.

Bu çalışmada, tam ve düz yarı dairesel olmak üzere iki farklı nemli nesne geometrisinin hava jeti ile kurutulmasının ısı transferi artışı ve nem miktarındaki azalışı üzerindeki etkisi sayısal olarak incelenmiştir. Jet kurutması, nemli nesneden sabit bir jet uzaklığında konumlandırılmış, laminer ve iki boyutludur. Tüm durumlarda, nemli nesnenin çapı, nemli nesneden olan jet uzaklığı ve jet giriş yüksekliği sabit alınmıştır. Farklı jet hızları için nesnelerin etrafındaki akım çizgileri ve eş sıcaklık eğrileri görselleştirilmiştir. Korunum denklemlerini çözmek için sonlu hacim yöntemi olan ANSYS Fluent 17.0 bilgisayar programı kullanılmıştır. Hesaplamalar, Re=100, 200 ve 300 olarak farklı Reynolds sayıları için gerçekleştirilmiştir. Çalışmanın, literatürde var olan sayısal ve deneysel çalışmayla iyi bir uyum içinde olduğu bulunmuştur. Sonuçlar, tam dairesel nemli nesnenin düz yarı dairesel nemli nesneden daha iyi ısı ve nem transferi performansına sahip olduğunu göstermiştir. Ayrıca, Reynolds sayısının artışının ısı ve nem transferi üzerinde olumlu bir etkiye sahip olduğu görülmüştür. Yerel olarak, jet kurutmanın nesnelerin ön taraflarındaki durma noktasına yakın daha etkili oldukları bulunmuştur.

Kurutma, gıdadan suyun uzaklaştırılarak uzun süreli depolama için en çok kullanılan yöntemlerden biridir. Kurutma ile gıdadaki su miktarı ve mikrobiyal aktivitenin önemli ölçüde azalması nedeniyle depolama boyunca meydana gelen fiziksel ve kimyasal değişimler en az seviyede olmaktadır. Bu çalışmada, iki farklı yeni nemli nesne geometrisi olan tam ve ters yarı dairesel nesnenin hava jeti ile kurutulmasının ısı ve kütle transferi artışı üzerindeki etkisi sayısal olarak incelenmiştir. Jet kurutması, nemli nesneden sabit bir jet uzaklığında (H) konumlandırılmış olup laminer ve iki boyutludur. İncelenen tüm durumlar için nemli nesnenin çapı, nemli nesneden olan jet uzaklığı ve jet giriş yüksekliği sabit olarak alınmıştır. Nesnelerin etrafındaki akım çizgileri ve eş sıcaklık eğrileri farklı jet Reynolds sayıları için elde edilmiştir. Korunum denklemlerini çözmek için sonlu hacim yöntemi olan ANSYS Fluent 17,0 bilgisayar programı kullanılmıştır. Hesaplamalar, Re = 100, 200, 300 olarak farklı Reynolds sayıları için yapılmıştır. Çalışmanın, literatürde var olan deneysel ve sayısal çalışmayla iyi bir uyum içerisinde olduğu bulunmuştur. Sonuçlar, tam dairesel nemli nesne geometrisinin ters yarı dairesel nemli nesne geometrisinden daha iyi ısı ve kütle transfer performansına sahip olduğunu göstermiştir. Ayrıca, Reynolds sayısının artışının ısı ve kütle transferi üzerinde olumlu bir etkiye sahip olduğu görülmüştür. Yerel olarak, jet kurutmanın nesnelerin ön taraflarındaki durma noktasına yakın daha etkili oldukları bulunmuştur.

Benford's Law is one of the mathematical methods that provide time, resource and cost advantage to the auditor while sampling in fraud auditing. This Law stipulates the frequency of occurrence of figures in different digits of the numbers in the data set. The auditor can have an idea about possible errors or frauds by looking at the distribution of the numbers in the data sets analyzed with Benford's Law. The aim of the study is to reveal the utility of Benford's Law in sample selection to reveal possible errors or frauds in auditing. The study was carried out on the 2019 accounting accounts of a state university. The analysis covers the figures in the sub-ledger records of 800 Budget Revenues and 830 Budget Expenses accounts. Within the framework of Benford's Law, "First Digit", "Second Digit" and "First Two Digits" tests were conducted using the numbers in the data set. In all tests, except for the "first two digits" test of the 800 Budget Revenues account, "acceptable fit" or "marginally acceptable fit" was determined between the frequencies of the numbers in the data set and Benford's Law. Looking at the results, it can be stated that the numerical analysis tests within the scope of Benford Law can be used by public auditors as a sample selection method. On the other hand, the fact that there is a mismatch between the data set and Benford's Law is not an absolute indicator of error or fraud should not be overlooked. [ABSTRACT FROM AUTHOR]

Copyright of Academic Platform - Journal of Engineering & Science is the property of Akademik Platform and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the important reasons for the popularity of circular hollow sections is an aesthetic appearance in terms of architectural point of view and engineering advantages. Therefore, they have been widely used, such as offshore structures, airports, exhibition halls, bridges, stadiums, etc. In such structures, space trusses consist of multiplanar Kjoints. However, there is no available design method of multiplanar K-joints made of circular hollow sections in the new steel structure design guide. The purpose of this study is to examine whether the current method of planar K-joint in the design guide is suitable for multiplanar K-joints. This study was carried out by using a nonlinear finite element method. Before the parametric study, the finite element model was validated against the test results. Mesh size, element type, boundary conditions and loading method determined based on the validation study were used in a series of parametric analyses. In parametric studies, the effects of the strength criterion, the geometric parameters of the chord and brace members, and the angle between the chord and brace members were examined. According to the results of numerical analysis, the planar K-joint methods in the current design guide can also be used to calculate the strengths of multiplanar K-joints. Lu’s deformation limit can be used to determine the resistance of multiplanar K-joints. The additional axial loads in the chord member may affect the resistance of joints. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The mining activities, one of the most important uses of natural resources, which causes environmental degradation and different effects depending on the mining operation type and size. At the beginning of these effects is acid mine drainage (AMD), which creates serious ecological risks on the environment both during operation and years after the mine is closed. AMD describes the formation of acid when sulphide-bearing (especially pyrite, pyrrhotite and chalcopyrite) mine wastes are exposed to oxidising conditions, typically in the presence of air (oxygen) and water, due to groundwater, rain and run-off. In this study, processes have been carried out to determine the occurrence of AMD in the ore stock and waste storage areas of the Gümüştaş Mining. The potential of AMD development and measures to be taken have been determined in case of possible occurrence of AMD. The mine operation area was located on the Eocene aged Alibaba Formation, which consists of andesite, basalt, and pyroclastics. The pH values in all samples indicate that they are class I. continental water resources quality and also the paste pH and sulphide (S-2) values suggest that there is no AMD potential in the mine operation area. This is supported by low mobility of major and trace element contents. In all samples, Net Neutralization Potential (NNP) and (Neutralization Potential Ratio) NPR values higher than 20 kgCaCO3/tone and 2 respectively, this indicate that the acid mining drainage don't formation in the area. Besides, AMD is not likely to occur in a short-term period according to very low S-2 values. In addition, compacted clay (50 cm thick) was laid in order to make impermeable in the stock area, and the resulting vertical profile was modeled in the finite element network system and water discharges determined. Consequently, all studies in the mining operation area show that the acid mining drainage formation was not expected in a short time period. However, in the area, environmental pollution caused by possible AMD for a long time will be prevented by measures to be taken.

Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Management & Economics Research is the property of Journal of Management & Economics Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the thermal behaviors of organic light emitting diodes (OLED) televisions are investigated experimentally and numerically. Organic light emitting diodes are very sensitive to temperature. For this reason, the heat emitted from the diodes must be removed quickly from the environment. The study consists of two parts. In the first part, the use of an effective heat spreader between the screen and the metal casing is proposed as a mechanism for improving the temperature distributions for heat transfer. Pyrolytic graphite plate and tempered pyrolytic graphite plate were used as heat spreader. The graphical heat transfer coefficients of the graphite plates are considerably higher than in the normal direction. The effectiveness of these proposed mechanisms is demonstrated by simulation. As an example model, OLED TV was selected in 15"dimensions and both experimental and numerical thermal analyzes were performed. The temperature distributions of the OLED were obtained with the help of the ANSYS ICEPAK program, a commercial code that uses the finite volume method. Simulation and test results are obtained very close to each other. The thermal management contributions of OLED TVs using different thicknesses of pyrolytic and tempered pyrolytic graphite plates are presented experimentally and numerically. In the second part, a dual action piezo fan design is proposed. The design parameters of the piezo fan were determined and the numerical analyzes for these parameters were made with the Comsol Multiphysics program. Experimental measurements were made for design dimensions determined by numerical analysis. The result is that the use of a dual-acting piezo provides more efficient cooling than the existing synthetic jets. [ABSTRACT FROM AUTHOR]

Refrigerated semi-trailers have the significant role on the transportation of fresh vegetables, foods, frozen products and animal origin foods. A typical refrigerated semi-trailer consists of a cooler unit, isolated upper structure and typical underframe. The subject of the present work is a heavy isolated semi-trailer which is generally used for the transportation of the frozen foods. Main aim of this work is improving the quality of transported foods and reduce the fuel consumption of trailer by means of better cooling performance. Therefore, air circulation of the inside of the common semi-trailer have been numerically modelled and inside of the semi-trailer have been re-designed to overcome to deficiencies which are seen in the first analysis. Numerical analyses have been compared with the test results. Finally, the new design also has been improved with the different air channel methodology. All results have been compared with each other and improvements have been showed. Final results have showed that the air channels let the homogeneous air distribution inside the refrigerated semi-trailer. [ABSTRACT FROM AUTHOR]

Beyaz eşya sektöründe ürünler genellikle genleştirilmiş polistren malzeme kullanarak ambalajlanmaktadır. Ürün ambalajlanıp tüketiciye ulaşıncaya kadar her an düşme ve darbe etkisinde kalma riskine sahiptir. Olası bir düşme nedeniyle hasar görerek kullanılamaz hale gelecek ürün, satışa hazır bir mamulün satılamaz hale gelmesi anlamına geleceği için kaynak kaybına yol açacaktır. Yüksek sayıda üretim yapan işletmelerde küçük oranda bile bu hasarın görülmesi toplamda ciddi maliyetlere yol açmaktadır. Bu nedenle, ürün fabrikadan çıkmadan önce düşme testine tabi tutulmaktadır. Bu testte fabrikadan çıkmaya hazır bir ürünün kullanılması ve testtin sık sık gerçekleştirilmesi nedeniyle testin masrafı oldukça fazladır. Testin doğal bir kısıtı ise çarpma sırasında ürünün dinamiklerinin ve ürünü oluşturan parçaların hareketlerinin ambalaj malzemesi nedeniyle tam olarak gözlemlenememesidir. Sunulan çalışmada bir fırın sayısal olarak modellenmiş ve farklı düşme senaryoları için davranışı incelenmiştir. Sayısal model gerçekleştirilen deneysel düşme testi sonuçları ile doğrulanmıştır. Böylece tasarım aşamasında düşme sırasında hasara uğrayacak parçaların belirlenmesi ve buna uygun iyileştirmelerin yapılması mümkün olmuştur.

Bird strike is a significant threat to aviation safety. Of all foreign object damages to aircraft, 90 % can be attributed to the bird strikes. Most bird strikes are occurred when an aircraft is at a low altitude during take-off and landing phases of a flight. To ensure flight safety, aviation regulations require a certain level of bird strike resistance for critical components (windward components such as nose, windshield, motor engine inlet, wing or tail leading edges). To meet these regulations, both bird strike tests are conducted experimentally and also analyses based on numerical simulation are made in computer environment due to expensiveness of these tests. Choosing the proper parameters in the tests and the analyses is very important in order to be able to pre-determine the damage following a real bird strike event and to design related components in accordance with these parameters. This paper reviews theoretical background, the finite element analyses (based on substitute bird materials, bird modelling methods, bird geometry) and related tests about bird strike problem. [ABSTRACT FROM AUTHOR]

In this work, the effect of drying with jet of air of two dissimilar moist thing geometries with whole and straight semi-circular on the enhancement of heat transfer and decrement of moisture amount was numerically examined. The drying jet had a laminar flow characteristic and two-dimensional jet situated at a fixed jet space from the moist thing. The moist thing diameter, jet space from the moist thing and height of jet initial were taken as stable in whole situations. Streamlines and isotherms were visualized around the things for dissimilar velocities of jet. A method of finite volume was used to figure out the conservation equations by employing software program of ANSYS Fluent 17.0. Computations were conducted for dissimilar Re, so, Re = 100, 200 and 300. It was obtained well accord with scalar and empirical output found in the reference. The results illustrated that the whole circular moist thing had greater good heat and moisture transfer performance than that of the straight semi-circular moist thing. Furthermore, it was seen that an increase of Re number had an affirmative effect on heat and moisture transfer. As locality, drying of jet was appeared to be most powerful close to the stillness point on the front face of the things [ABSTRACT FROM AUTHOR]

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)