TOJSAT - Volume 9 - Issue 2 - April 2019

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AN ARCHITECTURAL EVALUATION OF KONYA CITY

Fatih SEMERCİ, Hakan Taha ÇETİN

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Konya is an important city that has been home to different civilizations throughout history, has been used as a capital by the Seljuk State for a long time and extending to the neolithic turn of the past. The foundation of the historical city center of Konya started around the mound settlement known today as Alâeddin Hill. This area has been used centrally by different civilizations for many years and the most magnificent time of this area was the Seljuk period. The development of the historical city center was realized between Alâeddin Hill and Mevlana Tomb. The rich architectural content of different civilizations is clearly seen on this powerful axis. It contains many different artifacts belonging to the Seljuk, Ottoman and Republican era, where the architectural values that can be accepted as our cultural heritage of different periods are together and serve as a whole. This axis, which contributes to the rich architectural content of the city today, still maintains its vitality. With this study, the daily contribution of the historical city center was examined through the buildings. Alaeddin Hill - Mevlana Museum, which are contain many qualified building, has been accepted as an area study. The three qualified samples which are identified on the axis were analyzed in terms of historical, urban and structural, and the influence of these structures on the area was determined. The effects of urban and cultural heritage of architectural values are revealed in the analyzes made. As a result of these analyzes; It has been reached that the buildings give an identity to the center of the city and its surroundings, that it is an important factor in the perception of the places it is in, its reading and that it creates a focus  reflecting character of the its period.

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CASE STUDY OF THE IMPACT OF USING TECHNOLOGY IN SAUDI ARABIA PRIMARY SCHOOL IN SUPPORT OF TEACHING AND LEARNING WITH REGARD TO THE ENGLISH CURRICULUM

Mayada Abdulaziz Al Alharbi

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This paper reports on an experimental case study that aimed to explore the impact of the use of technologies in the teaching of English in a primary school in Saudi Arabia. In this study, the researcher applied various technologies such as an iPad, a computer, and a projector when teaching English language to the groups of Primary children.  These groups comprised of three different classes, while the traditional method of teaching, lecture style input was applied to control groups also made up of three age matched classes in the same school. The aim of using an experimental research approach was to determine the effectiveness of the technology when the teacher applied them in their English classes in a Saudi setting, and the effectiveness of using such technology in terms of the students’ achievements particularly when technology is not traditionally used to support teaching in this context. The analysis included both qualitative and quantitative. The results drawn from this study demonstrates evidence that the different technological devices do support English language learning in some students.

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DEFINING CLOUD COMPUTING

Mustafa OF, Burak Çakır

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With the development of computing technologies that have been at many points in our lives, cloud computing technology has begun to be used in a wide range of environments from a portable computer to a server computer. Accessibility is easy, cloud computing is at the top of the reasons for preference. Big companies in information technology (Microsoft, Google etc.) are leading the cloud computing services. It is thought that the installation of the cloud computing system is a big financial budget. However, a cloud computing system can be installed even in our home or office computers.  
Accessibility is easy, cloud computing is at the top of the reasons for preference.  Cloud computing facilitate access to data greatly. However, it should be known that the data are collected on the servers of the cloud computing service provider. In terms of importance, more or less important data are stored in cloud computing servers. It is important not to forget that in the event of a corruption of trust relations it will have serious results.
The aim of this work is to explain the installation steps of our own cloud computing server and client system on a virtual or real server system. It is to explain that a cloud computing system is easily installable. A cloud computing system can be set up in short steps and at low cost. In this way, contributed to the growth of national software works. The data is stored in cloud computing servers, one or more national and reliable institutions.

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DETERMINATION OF PHYSICAL AND MECHANICAL PROPERTIES OF POLYPROPYLENE FIBRE CONCRETE

Hakan SARIKAYA, Gülşah SUSURLUK

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In this study, it is aimed to investigate the physical and mechanical properties of concretes obtained by using polypropylene fibers at different ratios by keeping amount of cement constant in the concrete mixtures. According to experimental results, it was seen that the increasing fiber dosage in the concrete mixtures, flexural strength and ultrasonic velocity was increased by addition of fibers to concrete, compressive strength and slump was decreased.

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DEVELOPMENT OF MESH-STRUCTURE APPLIED GUM METAL ARTIFICIAL MEDICAL PRODUCTS

Jianmei HE

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It is interested in this study to develope mesh-structure applied Gum Metal (one kind of titanium alloy, also called Gum Titanium) plates with high biocompatibility, elastic deformability and comparatively lower elastic modulus for implant applications. Meshed gum metal plates with excellent 3-demensional flexibility and light-weight performance compared to usual metal plate implants are designed parametrically using 3D CAD tools for different bone graft applications. Mechanical properties like tensile/compression and bending stiffness and volume densities of sample meshed gum metal plates are experimentally and analytically evaluated with respect to different design parameters like basic mesh shapes, mesh line width etc.

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DIFFERENTIATION OF BUILDING WITH THE COMMUNITY CONCEPT FROM EXISTING MODELS, AND ITS IMPLEMENTATION IN PROJECTS IN AFRICA

Hakan Taha Çetin, Fatih Semerci

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Building with the community, which is starting to construction with training of labors to construct their vernacular in larger scale, became a trend in 80s and 90s in Africa in order to not only to construct building but also to develop society and it drew apart a different path from existing models. This research examines the rationale of this architectural trend by focusing on mostly projects which won Aga Khan Architectural Award (AKAA) like Halawa House by Abdel Wahed El-Wakil, Yaama Mosque by El Hadji Falke Barmou and Gando Primary School Francis Diebedo Kere and socio-economic and cultural backgrounds of their locations. The preliminary results of the research show that this technic gave chance to society both to survive in such a bad condition by gaining necessary skills and to implement these skills in other buildings forms like schools and hospitals which have a great importance for the development of the society with low-cost solutions. The conclusion can also be drawn that how the way of implementing architecture helps communities in the form of sociological, psychological and economical aspects.

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DYNAMIC MIXING OF ADIPRENE® L-100

Matt Jackson, Emily Hunt, Benton Allen

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This project used a dynamic mixing system purchased from BDTronics to investigate automatic mixing and dispensing of polyurethane formulations to replace archaic hand mixing techniques at Pantex Plant that resulted in poor quality parts and inability to have good repeatability between results on lots of material. Over the course of approximately 18 months several curing agents and secondary extenders were evaluated but Ethacure® 300 and 1,4 butandiol were found to be the most similar to the previous curatives. Room temperature and heat cured formulations were identified to meet the needs of Pantex Plant Plastics Shop. By varying the formulation using the plasticizer benzylbutylphthalate (BBP), Ethacure® 300, and 1,4 butanediol, and adjusting the curing time and temperature, to the final physical properties were adjusted to include compression, tear, hardness, and tensile strength. A modeling study evaluated molds using a software package called Moldflow®. Moldflow® software helped determine the best points to place injection holes, vent holes and identified if damming issues or void formations would occur. This study determined that the new formulations as well as new colorants identified would be a good replacement for the production tools used at Pantex Plant.

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EFFECT OF PRANDLT NUMBER ON TURBULENT HEAT TRANSFER OF CORRUGATED TRAPEZOIDAL PLATE HEAT EXCHANGERS USING NANOFLUIDS

Elif Büyük Öğüt, Seda Dilki

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In this study, fully developed turbulent flow and heat transfer behavior of water, ethylene glycol, mercury and propane based nanofluids in a corrugated trapezoidal plate heat exchanger have been numerically investigated. A constant heat flux was applied to the heat exchanger and the constant heat flux was chosen to be 6 kW / m2, volume fractions ϕ=0%-4%, diameter d = 20 nm and Al2O3 was selected as nanoparticle.The Reynolds number varies from 6000 to 20000. Geometric parameters of the corrugated trapezoidal channel, trapezoidal height e=5mm, trapezoidal pitch Pe=12mm, width of the top trapezoidal channel w=3mm. Executive equations have been solved with Ansys Fluent  programme. The velocity distribution,temperature contours,pressure drop, average Nu number and thermal-hydraulic performance have been analyzed and presented. The effects of nanofluids have been examined on heat and flow fields and it has been observed that the heat transfer increases together with the nanoparticle volume concentration. When the nanofluid is used in a forced convection, the amount of heat transfer increases as the Prandtl number increases. The highest value of the average Nusselt number was obtained in the ethylene glycol-based nanofluid, and the lowest value was obtained in the mercury-based nano-fluid.Results show that the use of nanofluid in the corrugated trapezoidal channel increases the thermal performance of systems and thus contributes to the design of more compact heat exchanger.

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EVALUATION OF OCCUPATIONAL SAFETY AND HEALTH IN THE GLOBAL FISHING SECTOR

Veysel TATAR

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Commercial fishing is one of the most hazardous occupations causing over 24,000 fatalities each year, the large majority of which occur aboard small fishing vessels. The International Maritime Organization (IMO), which is the United Nations body that has the primary responsibility for maritime safety and the protection of the marine environment, has taken on the responsibility of redressing the situation. Occupational Health and Safety (OHS) can simply be defined as providing secure working conditions for the employees. Employee safety issues are becoming more and more important every day, not only in working environments but also in every activity within the societies. Safety can be considered at both individual and institutional levels. The fishing industry (or fishing sector) is extraordinarily diverse. At one extreme are large, multinational joint ventures, utilizing large factory trawlers and numerous other vessels, employing thousands of workers on several oceans. At the other are small, wooden canoes and other boats used by individual fishermen' to catch sufficient food for their families and perhaps more to sell in their local communities. Most fishing operations fall somewhere between these extremes. The technology used can be simple and traditional, or it may be highly sophisticated, incorporating the most advanced electronic and other equipment. This paper analyses the role of OHS, occupational accidents, occupational diseases, risks and legislation are mentioned in the fishing industry.

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EXPERIMENTAL INVESTIGATION OF MACHINABILITY PROPERTIES OF 5035 STEEL

Ayhan AYTAÇ, Muhammed İLİVAN

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One of the main purposes in machining is to bring surface roughness to the top level. The stage where the most decisive work can be done in improving the product quality is the parameter design phase for both product and process design. In order to determine the most effective parameters and to evaluate the results more efficiently, the Taguchi experiment design technique is preferred to realize the experiments in a shorter time. This performed study was done by the aim of investigating the effect of change in terms of hardness, feed rate, and cutting tool of “Dual Phase” steel, which is a class of HSLA (High Strength Low Alloy) steels that increases usage and importance day by day, on surface quality in turning process in the pieces subjected to high forces in machine, device, car manufacturing. Experimental design In the Minitab statistical analysis program, Taguchi experiment design technique and 9 trials according to L9 orthogonal design. Experiments were performed in dry cutting conditions in CNC Turning Table that has 1.5 kW power and rotates with maximum 2000 rpm. Variance analysis and signal / noise ratio were used in the evaluation of the test results. . It was possible to achieve the intended results with only one third of the number of experiments required in full factorial design (9 experiments instead of 27). In the experiments, the cutting tool type (CBN, Ceramic and Carbide cutter), the feed rate (0,02, 0,04 and 0,06 mm/cycle) and the material hardness (Material with two different hardness values obtained by annealing at 745 and 760 degrees without heat treatment and obtained after heat treatment) were used as the independent variable (factor). The mean surface roughness value (Ra) as a dependent variable was determined from measurements taken at 6 different points in three trials. As a result, the most effective parameters on the surface quality are the feed rate, the material hardness (microstructure) and the cutting tool. The results obtained are interpreted together with the evaluations which have been entered into the literature before.

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IMPROVEMENT OF SELF-LOOSENING PREVENTION EFFECTS OF THREADED FASTENERS THROUGH FINITE ELEMENT ANALYSIS

Atsushi NOMA, Jianmei HE

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Threaded fasteners using screws/bolts are used not only in industrial field but also in various fields such as precision instruments and medical field. Many accidents caused by the loosening of the screw/bolt threaded fasteners are actually reported. As one countermeasure, nut with spring washer is used, but there remains the problem that effective loosening prevention effects cannot be obtained in the case of increasing in the parts number or no-using of such nuts etc. Then further improvement on loosening prevention effects of screw/bolt threaded fasteners are desired. In this research, new screw/bolt structures having self-loosening prevention effects are designed by applying the spring characteristic swelling effects in loosening direction of springs. 3D CAD modeling and finite element analyses are carried out to evaluate the spring characteristic effects and self-loosening prevention effects of new designed screw/bolt structures. Analytical results indicated that self-loosening prevention effects can be affected by the shape/size design variables of applied helical cuttings introduced for new screw/bolt structures.

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IMPROVEMENT ON TENSILE STRENGTH AND FATIGUE PERFORMANCES OF MESHED GUM METAL PLATES FOR BONE GRAFT APPLICATIONS

Koki SEKIGUCHI, Jianmei HE

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Degenerative intervertebral discs have a sign of epidemic as one of diseases caused by aging and lifestyle habits. Currently practiced treatments called spinal fusion surgery using pure titanium or titanium alloy implant products have the problems like overloading on healthy nature bones caused by the extra stiffness and heavy weight of such metal implants. Therefore, creation of implant products that meets mechanism like density, elasticity/rigidity of nature bones are required to reduce the burden on patient's health bones. Meshed titanium plates for bone graft applications have improved with excellent three-dimensional (3D) flexibility, lower elastic modulus and higher strength in previous studies. In this study, mesh structures as applied on Gum Metal plates with high biocompatibility are interested and their tensile strength/fatigue performance are investigated through analytical and experimental approaches for implant application on intervertebral disc defections. Based on different basic mesh shapes designed in this study, sample meshed Gum Metal plates were fabricated by laser cutting process and tensile fatigue experiments were executed. It concluded that high strength and fatigue performance of meshed Gum Metal plates can be obtained by using with some kind of designed basic mesh shapes.

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INVESTIGATION ON DEVELOPMENT OF HIGH PERFORMANCE MEDICAL STENTS AS APPLIED WITH MESH STRUCTURES

Shoji ASANO, Kazuki HIRAYAMA, Jianmei HE

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There are concerns about the occurrence of fatigue fractures caused by stress concentrations due to different shape structures and manufacturing methods in conventional stents, and then new stents having high strength and high flexibility are required. Applicable mesh structures for medical stent applications based on the design concepts of high strength and flexibility are designed to solve various problems of conventional stents in this research. The influence of introduced design variables of basic mesh shapes on compression characteristics of meshed stent models are evaluated through finite element analysis using ANSYS Workbench. From analytical results, compressive stiffness of meshed stent models are found to be changed periodically with compressive directions due to the designed basic mesh shapes. Secondly, compressive flexibility of meshed stent models mostly depends on arm’s number and shapes of basic mesh shapes. It concluded that the compressive performance of designed meshed stent models in this study can be easily controlled by increase some design variables like angle proportional to the arm length of designed basic mesh shapes and get closed to conventional medical stents with higher strength performances.

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IS TURKEY REALLY A GLOBAL COMPETITOR IN YACHT BUILDING INDUSTRY?

Murat AYDIN, Tuğba Yılmaz AYDIN

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As it is well known, Turkey took place near the top of 24m or longer yacht building countries. In the world there are a few leading countries which dominate both production and other processes. In recent years, Turkey is one of the yacht building centers in the world and attracts not only key players’ interest but also tourists’ with long and beautiful coastal lines and long sunny season. From this point of view, Turkish yacht building industry investigated in terms of design and engineering, yards locations, yacht types, project length, installed engine, transmission or propulsion systems, navigation and telecommunication systems, generator, hull and superstructure materials and classification in this study. According to the results, it can be said that Turkey has lots of advantages to compete with the leading players of this industry but must be focused on added value activities to increase its share from the market.

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LINEAR MULTISECRET-SHARING SCHEMES

Selda Çalkavur

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Cyclic codes form an important class of linear codes. These codes have a rich algebraic structure. Secret sharing is a major topic of cryptography. In this paper, we present a multisecret-sharing scheme based on cyclic codes. This scheme is linear in the sense of that form of each secret. Its security improves on that of multisecret-sharing schemes.

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