Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering最新文献

{"title":"CONTRIBITION OF MICRO-SILICA AND NANO-MONTMORILLONITE REINFORCEMENTS ON THE MECHANICAL PROPERTIES OF UV-CURABLE THERMOSET RESIN","authors":"A. Kandemir, Arda Baytaroğlu","doi":"10.18038/estubtda.899963","DOIUrl":"https://doi.org/10.18038/estubtda.899963","url":null,"abstract":"UV-curable thermoset resins had been utilized in organic coating industry because of their benefits over conventional adhesives like fast curing, less energy consumption and equipment. In this article, the effects of micro and nano-scaled reinforcements on the mechanical properties of a UV-curable thermoset resin were investigated. The reinforcements are chosen to be nano-scaled Montmorillonite (MMT) and micro-scaled Silica (SiO2). The reason for this choice is that the aforementioned particles are non-toxic, low-cost and in the case of MMT; abundant in nature. According to our knowledge, there is no study on the synergistic effects of those two additives in thermoset resins. \u0000The instrumented microindentation test results reveal that maximum improvement on hardness (288%) was achieved by single addition of MMT thanks to the well-distributed silicate layers. Conversely, SiO2 addition diminished both strength (-51%) and modulus (-68%) drastically which is attributed to the possible poor dispersion and weak surface attraction. On the other hand, when those additives were utilized together, the property improvements namely; hardness and modulus are observed to be in between of single addition of either additive. It is suggested that SiO2 contribution does not disturb intercalated/exfoliated-MMT structure and similarly by simultaneous MMT reinforcement, quality of SiO2 dispersion is not affected. It is concluded that one benefit of these SiO2-MMT combinations over single MMT reinforcement could be related to plasticity since they result in less plasticity reduction of -22%-27% compared to MMT (-43%) with the further benefit of higher hardness improvement (+66%) than bare SiO2 addition (-51%).","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114631584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COMPUTATIONAL ANALYSIS FOR DESIGN DEVELOPMENT EVALUATION IN SPATIAL PLANNING","authors":"Hemza Boumaraf, M. Inceoğlu","doi":"10.18038/estubtda.1170171","DOIUrl":"https://doi.org/10.18038/estubtda.1170171","url":null,"abstract":"The influence of new technological software on architectural design is increasing with every passing day. This led to new horizons discovery in spatial analysis and design interpretation and extended by engaging different techniques based on computational design and human-computer interaction. Throughout the architectural design process, decision-making on spatial performance parameters such as visibility, density, and building typology is frequently taken by examining a limited number of materials. They are conventionally optimized by employing repetitive experimentations without systematically evaluating the complete range of potential designs and their efficient outcomes. A computational design analysis approach of spatial morphological structure based on several indicators is presented in response to this challenge. This research compares contextual spatial analysis with computational methods and determines the consistency of Eskisehir technical university master plan expansion mechanisms through the relationship between layout and spatial arrangement, connectivity and accessibility, and built area and open space of the university map in two different periods (2005/2020). For density measurements, Ground Space Index (GSI), Floor Area Ratio (FAR), and Open Space Ratio (OSR) calculations in urban spatial planning are analyzed. Furthermore, the Isovist analysis (Attractiveness, Extent of observation, line of orientation, and arrangement) and their visual quality was examined using the logical interpretation approach. The collected visual and numerical data show that the visual quality of the observer's full view, as seen from the center of the university campus master plan, is directly related to the open space and built environment. The visibility and density characteristics of the university campus master plan showed that these analytical techniques are very responsive to the design limitation and context requirements. The presented application has evaluated the visual aspects of each of the university campus maps to deliver a technique to the designers so that they may implement their requested visual characteristics in future design expansion.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127550661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DIGITAL POSSIBILITIES OF THE ATMOSPHERE: METAVERSE AND HALLUCINATORY IMAGE","authors":"S. Hatıpoğlu, Cansu Tatli","doi":"10.18038/estubtda.1170931","DOIUrl":"https://doi.org/10.18038/estubtda.1170931","url":null,"abstract":"Considering the propositions of the virtual universe with its short history, there are digital twins and various economic investments. While the Metaverse points out a novel universe, it is able to promise much more than producing a copy of the self and imitation of conventional economic interactions. To reveal these potentials, it is necessary to determine the areas that must be meticulously focused on. Although Metaverse has permeated daily life dialogues, studies in the academic field are limited. Likewise, research about its architecture and space needs to be developed in this area. No matter how far the new universe propositions go, they still stick with the quantitative values of the physical world. This issue obstructs the creation of its own reality. However, the universe's own digitalized digitalised structure does not require that the imagination of the spaces stuck with a quantitative basis. To avoid quantitative and reductive attitudes, focusing on the atmosphere of this universe may be a solution. The study aims to collide the possibilities of the Metaverse and the architectural atmosphere discussions to make an alternative reading of the Metaverse. Developing theories about the atmosphere of spaces and conducting atmospheric studies about Metaverse allow us to develop meta-experiences of the Metaverse. Focusing on the architectural atmosphere, immediate appreciation, ecstatic being and hallucinatory image will deepen the definition of Metaverse and provide a multi-layered experience. The image of the atmosphere and ecstatic being is associated with a ‘hallucinatory image'. The hallucinatory image has a structure that does not narrow down its references to the physical world. With this aspect, it may provide forms of alternative perceptions specific to the Metaverse. The hallucinatory image, parallel with the sensation of an ecstatic being, stimulates us to sense the atmosphere produced by the Metaverse.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131636067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"APPLICATION OF HOOKE’S LAW TO ANGLE PLY LAMINA","authors":"Ç. Yılmaz, H. Q. Ali, M. Yildiz","doi":"10.18038/estubtda.1054195","DOIUrl":"https://doi.org/10.18038/estubtda.1054195","url":null,"abstract":"Aerospace-grade carbon fiber reinforced polymer composite plates with four different fiber orientations 0º, 30º, 45ºand 60º is produced with the autoclave curing method and subjected to tensile testing. The stress-strain curves of the composite specimens are compared with Hooke’s law. It is observed that Hooke’s law coincides precisely with the experimental results for samples containing fibers parallel to the loading direction. However, it does not coincide with samples where the fibers make a certain angle with the applied load direction.. Moreover, it is reported that Hooke’s law converges the experimental results for small strain values but diverges significantly from the experimental results at higher strain values.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128364981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CHARACTERIZATION OF ARTIFICIALLY GENERATED 2D MATERIALS USING CONVOLUTIONAL NEURAL NETWORKS","authors":"Cahit Perkgöz, Mehmet Zahit Angi̇","doi":"10.18038/estubtda.1149416","DOIUrl":"https://doi.org/10.18038/estubtda.1149416","url":null,"abstract":"İki boyutlu (2B) malzemeler, bu malzemelerin ürettiği cihazların yüksek performans göstermesi nedeniyle birçok araştırmacının ilgisini çekmiştir. 2B malzeme elde etmek için solüsyon tabanlı kimyasal sentez, kimyasal buhar biriktirme (KBB), moleküler ışın epitaksisi, atomik katman biriktirme, darbeli lazer biriktirme (DLB) gibi işlemler sırasında saatler gerektiren farklı üretim yöntemleri bulunmaktadır. 2B yapılar elde edildikten sonra, kusurları da dahil olmak üzere özellikleri farklı karakterizasyon araçları ile ortaya çıkarılmalıdır. Karakterizasyon süreci de üretim süreci gibi zaman ve uzmanlık gerektirir. Bu açıdan, üretilen örneklerin pratik ve hızlı sınıflandırılması için Evrişimli Sinir Ağları (ESA) gibi derin öğrenme yöntemleri bir çözüm olabilir. Ancak, yukarıda bahsedilen uzun deneysel süreçler nedeniyle araştırma laboratuvarlarının çoğunda yeterli sayıda örnek bulunmamaktadır. Bu çalışmada, farklı elektronik uygulamalarda yüksek potansiyele sahip, yaygın olarak çalışılan bir 2B yarı iletken olan MoS2'nin yapay olarak oluşturulmuş görüntülerini kullanan bir CNN algoritmasının performansı sunulmaktadır. Normal ve kusurlu MoS2 pullarını içeren sentetik optik mikroskobik görüntüler, Fresnel Denklemleri kullanılarak farklı malzemeler üzerine gelen ışığın yoğunlukları ile oluşturulur. Normal ve kusurlu örnekleri tespit etmek için derin bir CNN algoritması oluşturulmuştur. Doğruluk ölçümlerinin sonuçları, CNN'nin gelecekte yeterli sayıda gerçek görüntü ile iki boyutlu malzemelerin karakterizasyonu için kullanılabileceğini göstermiştir.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121420283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"HİDROTERMAL KARBON İÇERİĞİNİN POLİETİLEN MATRİSLİ KOMPOZİTLERİN AŞINMA ÖZELLİKLERİNE ETKİSİ","authors":"Yasin Akgül","doi":"10.18038/estubtda.1038059","DOIUrl":"https://doi.org/10.18038/estubtda.1038059","url":null,"abstract":"Compared to commonly use carbonaceous materials such as carbon nanotubes or graphene nanoplatelets, hydrothermal carbons (HTCs) are obtained with environmentally friendly approaches at a lower cost. Although HTCs have a wide application area such as batteries, magnetic materials, supercapacitors, adsorbent materials, etc., there are few studies on the usage of HTC as reinforcement material for composites. In this study, polyethylene matrix composites containing different amounts (0.5 wt.%, 1 wt.%, 2 wt.%) of HTCs were fabricated via the injection molding process. The effect of HTCs content on the wear properties of polyethylene matrix composites was investigated. Reciprocating wear tests were performed applying different loads at dry sliding conditions. To correlate with wear results, the mechanical properties of samples were determined by tensile and impact tests. Also, FTIR and DTA analyzes were conducted to understand the effect of HTCs on the structural and thermal properties of composites. Results show that the addition of HTCs led to the enhancement of mechanical and tribological properties of polyethylene at lower amount reinforcement ratios. Thus, it can be said that HTCs could be alternative carbonaceous reinforcement material for polymer matrix composites.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126609303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ANALYSIS OF THE COLLISION EFFECT FOR ADJACENT STRUCTURES IN THE TIME-FREQUENCY DOMAIN","authors":"Ömer Fatih Sak, K. Beyen","doi":"10.18038/estubtda.975913","DOIUrl":"https://doi.org/10.18038/estubtda.975913","url":null,"abstract":"Many reinforced concrete structures are built side by side in our cities. There are very few applications of earthquake joints in adjacent apartment buildings, most of them were constructed completely adjacent. Adjoining buildings or any property should be protected from damage or collapse during construction, restoration and demolition work. In case of the static condition, protection must be supplied for foundations, walls and roofs. We have already observed many building collapses in Turkey with a great number of life lost. For the constructed buildings, there is a need to understand the structural system of an existing building to manage risk. In case of earthquakes like dynamic loading, earthquake joints are essential. The Turkish Building Earthquake Code (TBEC) 2018 requires calculations of vertical joints for some types of structures. Earthquake joints should be left in the gap calculated for structures of some height. It is thought that this gap will prevent the structures from colliding. However, it has been the subject of research how the performance of the building will change when it is produced adjacent or when floor offsets cause collisions at earthquake joints. In this study, structures of different heights were analyzed in the time domain for specific earthquake motions. Collision situations of more than two buildings are discussed by making a street model. Structural performances of discrete and adjacent structures obtained from nonlinear analysis were compared. The motion parameters obtained from the structures were analyzed in the time-frequency domain by wavelet and Hilbert transforms. To determine the effects of earthquake joints, condition assessment and damage detection studies were carried out and the sufficiency of seismic joints was discussed.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123147641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"HIGH BRIGHTNESS 1908nm TM-DOPED FIBER LASER WITH POWER SCALING TO >75W","authors":"S. K. Kalyoncu","doi":"10.18038/estubtda.1072801","DOIUrl":"https://doi.org/10.18038/estubtda.1072801","url":null,"abstract":"In this paper, we have studied monolithic diode-pumped Tm-doped fiber laser to be used as a pump source for Ho-YAG systems. The cavity is designed to achieve high optical-to-optical efficiency and robustness against amplified spontaneous emission (ASE) induced parasitic lasing via optimizing the doped fiber length and cavity parameters. Experimentally, we have demonstrated 1907.7 nm fiber laser with an output power of 79 W from 10/130 μm Tm-doped double clad fiber, enabling high brightness and radiance density as well. The laser cavity has a slope efficiency of ~55%, ASE suppression of > 40 dB and a near-diffraction-limited beam quality of M2~1.07.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125284150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SOLAR ENERGY ASSISTS SEDIMENT MICROBIAL FUEL CELL TO GENERATE GREEN ENERGY FROM LIQUID ORGANIC WASTE","authors":"Onur Can Türker","doi":"10.18038/estubtda.1031449","DOIUrl":"https://doi.org/10.18038/estubtda.1031449","url":null,"abstract":"Simultaneous liquid organic waste disposal and electricity generation were achieved by a solar-assist sediment microbial fuel cell (S-SMFC) in terms of an ecological and economical perspective. In this respect, 840 mL house environment liquid organic waste which contains 10% juice and 10% sugary tea were disposed by electrogenic bacteria and converted electricity with solar energy. A 100 F capacitor was easily charged 29 times with generated electricity. S-SMFC was disposed 10 mL more waste than control due to more electrical bacteria density on the graphite electrode. In this case, Proteobacteria and Firmucutes were categorized dominate bacteria groups, and they were found in the S-SMFC as 54% and 28%, respectively. Importantly, solar energy increased population density of these groups in the S-SMFC and the density on the graphite electrode increased more than 19% according to control. Some bacteria which were associated with electricity production in the S-SMFC were to Azospirillum fermentarium, Clostridium sp., Pseudomonas guangdongensis, Bacteroides sp., Azovibrio restrictus, Clostridium pascui, Levilinea saccharolytica, Seleniivibrio woodruffii, Geovibrio ferrireducens. Consequently, S-SMFC presents innovative, crucial and simple methodology in order to convert liquid organic waste into the green energy.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124741542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PREDICTING MYOCARDIAL INFARCTION COMPLICATIONS AND OUTCOMES WITH DEEP LEARNING","authors":"I. Yavru, Sevcan Yilmaz Gündüz","doi":"10.18038/estubtda.1056821","DOIUrl":"https://doi.org/10.18038/estubtda.1056821","url":null,"abstract":"Early diagnosis of cardiovascular diseases, which have high mortality rates all over the world, can save many lives. Various clinical findings and past histories of patients play an important role in diagnosing these diseases. These days, the prediction of cardiovascular diseases has gained great importance in the medical field. Pathological studies are prone to misinterpretation because too many findings are studied. For this reason, many automatic models that work with machine learning methods on patients' findings have been proposed. In this study, a model that predicts twelve myocardial infarction complications based on clinical findings is proposed. The proposed model is a deep learning model with three hidden layers with dropouts and a skip connection. A binary accuracy metric is used for measuring the performance of the proposed method. Rectified Linear Unit is set to the hidden layers and sigmoid function to the output layer as an activation function. Experiments were performed on a real dataset with 1700 patient records and carried out on two main scenarios; training on original data and training on augmented data with 100 epochs. As a result of the experiments, a total accuracy rate of 92% was achieved which is the best accuracy rate that has been proposed on this dataset.","PeriodicalId":436776,"journal":{"name":"Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering","volume":"54 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132569656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}