IYTE GCRIS Database (Izmir Institute of Technology)
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3d Modelling as a Tool for Heritage Presentation: Digital Reconstruction of 19th Century Gülbahçe, Urla, İzmir
No full textBu tez, 19. yüzyılda varlıklı bir nahiye merkezi olan ve bu zenginliğin yapılı çevreyi de şekillendirdiği; ancak günümüzde bu özelliklerini büyük oranda kaybetmiş olan Gülbahçe'nin kaybolan mirasını yorumlamak ve sunmak amacıyla dijital ortamda yeniden inşa edilmesini amaçlamıştır. Bu doğrultuda, 19. Yüzyılın Gülbahçe'si geometri tabanlı modelleme yöntemi ile modellenmiştir. Modelin güvenilirliğinin sağlanabilmesi için Türkiye ve Yunanistan'da bütün literatür ve arşiv kaynakları taranarak Gülbahçe'ye dair bilgiler derlenmiştir. Bunun sonucunda üç boyutlu dijital model, yerleşim bütünü ve etkileşim içinde olduğu çevresini de kapsayarak ve günümüzde artık var olmayan öğeleri de içerecek şekilde gerçekleştirmiştir. Bunlara ek olarak bu çalışma dijital rekonstrüksiyonu gerçekleştirilen her bir yapının güvenirlilik derecesine göre geliştirilen sunum yöntemi ile Londra Tüzüğü'nde önerildiği gibi, yalnızca dijital kopyaların oluşturulmasının ötesine geçerek görselleştirme süreçlerinin ve sonuçlarının kullanıcılar tarafından doğru şekilde anlaşılabilmesini ve değerlendirilebilmesini sağlamaktadır.The aim of this thesis is to digitally reconstruct Gülbahçe, a wealthy town centre in the 19th century, where the town's wealth shaped its built environment. Currently, most of these unique characteristics have disappeared. The purpose of this project is to interpret and present the lost heritage of Gülbahçe in a digital environment. The 19th century Gülbahçe was modelled using a geometry-based modelling method with the specific aim of achieving this final result. In order to ensure the reliability of the model, all the literature and archival sources in Turkey and Greece were examined, and information about Gülbahçe was compiled. As a result, the three-dimensional digital model effectively presented the inaccessible lost heritage, providing a comprehensive view of the built environment and cultural landscape at the settlement scale. Furthermore, the presentation method developed according to the degree of reliability of each digitally reconstructed building goes beyond the creation of digital copies, as recommended in the London Charter, and ensures that the visualisation processes and results can be properly understood and evaluated by participants
Unifying Behavioral and Feature Modeling for Testing of Software Product Lines
No full textExisting software product line (SPL) engineering testing approaches generally provide positive testing that validates the SPL's functionality. Negative testing is commonly neglected. This research aims to unify behavioral and feature models of an SPL, enable testing before and after variability binding for domain-centric and product-centric testing, and combine positive and negative testing for a holistic testing view. This study suggests behavioral modeling with event sequence graphs (ESGs). This heterogeneous modeling strategy supports bottom-up domain testing and top-down product testing with the feature model. This new feature-oriented ESG test creation method generates shorter test sequences than the original ESG optimum test sequences. Statechart and original ESG test-generating methods are compared. Positive testing findings are similar. The Statechart technique generated 12 test cases with 59 events, whereas the ESG technique created six test cases with 60 events. The ESG technique generated 205 negative test cases with 858 events with the Test Suite Designer tool. However, the Conformiq Designer tool for the Statechart technique does not have a negative test case generation capability. It is shown that the proposed ESG-based holistic approach confirms not only the desirable (positive) properties but also the undesirable (negative) ones. As an additional research, the traditional ESG test-generating approach is compared to the new feature-oriented method on six SPLs of different sizes and features. Our case study results show that the traditional ESG test generation approach demonstrated higher positive test generation scores compare to the proposed feature-oriented test generation approach. However, our proposed feature-oriented test generation approach is capable of generating shorter test sequences, which could be beneficial for reducing the execution time of test cases compared to traditional ESG approach. Finally, our case study has also shown that regardless of the test generation approach, there has been found no significant difference between the Bottom-up and Top-down test strategies with respect to their positive test generation scores
High Entropy (hftizrvnb)b2 Ceramic Particulate Reinforced Al Matrix Composites: Synthesis, Mechanical, Microstructural and Thermal Characterization
No full textThis study aims to introduce a novel type of particulate reinforced Al matrix composite. High entropy (HfTiZrVNb)B2 ceramic particulate reinforced Al matrix composites were produced via a combined process of different powder metallurgy methods. Firstly, boride compounds (HfB2, TiB2, ZrB2, VB2, NbB2) were synthesized in the laboratory scale using the related metal oxide, boron oxide, and magnesium by mechanochemical synthesis (MCS) and leaching processes under optimum conditions. Secondly, the synthesized and purified boride powders were mixed in equimolar ratios using a planetary ball mill for 72 h, and they were sintered at 2000 °C under 30 MPa via spark plasma sintering (SPS). Thirdly, equimolar high entropy (HfTiZrVNb)B2 bulks were crushed, converted into powder forms, and added into Al powders at different amounts as 1, 2, 5, 10, and 15 wt %. Lastly, these powder blends were mechanically alloyed in a vibratory ball mill for 6 h, cold pressed and pressureless sintered at 630 °C for 2 h. For characterization techniques, X-ray diffractometry (XRD), thermal analysis, scanning electron microscopy/energy dispersive spectrometry (SEM/EDS), density measurements using pycnometer and Archimedes' methods, microhardness and dry sliding wear tests were conducted on the sintered composites. The highest hardness (∼1.5 GPa) and the lowest wear rate (∼0.0012 mm3/Nm) were obtained in the Al-15 wt % (HfTiZrVNb)B2 sample. © 2024 Elsevier Ltd and Techna Group S.r.l
Genetic Factors Associated With Age-Related Macular Degeneration Modulating Plasma Inflammatory Biomarker Levels in Patients With Aids
No full textIntroductionPatients with the acquired immunodeficiency syndrome (AIDS) have an increased prevalence and incidence of intermediate-stage age-related macular degeneration (AMD). Several elevated plasma inflammatory biomarkers are associated with increased incidence of intermediate-stage AMD in this population. We evaluated the association between AMD risk alleles and plasma inflammatory biomarker levels in persons with AIDS.Materials and MethodsCryopreserved plasma specimens of 229 non-Hispanic White and 252 non-Hispanic blacks from the Longitudinal Study of the Ocular Complications of AIDS cohort were assayed for plasma levels of soluble tumor necrosis factor receptor (sTNFR) 2, interleukin (IL)-18, C x 3motif chemokine ligand 1 (CX3CL1), C-reactive protein (CRP), and soluble CD14 (sCD14). Genotyping included AMD-associated variants rs10801553 and rs800292 for complement factor H (CFH) rs9332739 and rs547154 for complement factor 2 (C2), rs2230199 for C3, rs2285714 for CFI, and rs3732379 and rs3732378 for C x 3motif chemokine receptor 1 (CX3CR1).ResultsIn Whites, AMD low-risk CX3CR1 variants (V249I and T280M) were associated with reduced plasma levels of IL-18. In Blacks, AMD low-risk C3 R102G and low-risk CX3CR1 T280M variants were associated with reduced CRP levels.ConclusionsGenetic variants in AMD-associated immune genes may influence AMD-associated systemic plasma inflammatory biomarker levels in patients with AIDS
Tailored Bodipy-Based Fluorogenic Probes for Phosgene Detection: a Comparative Evaluation of Recognition Sites
No full textWe constructed two novel boron-dipyrromethene (BODIPY)-based fluorescent probes, BOPD and BOBA, each equipped with the phosgene specific recognition units o-phenylenediamine (OPD) and o-aminobenzylamine (OBA) at the 2-position of the BODIPY core. BOPD and BOBA represent rare examples of BODIPY-based probes that operate by modulating an intramolecular charge transfer process (ICT), as validated by computational studies. We systematically compared the analytic performance of those recognition units while focusing on selectivity, fluorescence turn-on ratios and response times. Probe BOBA, equipped with OBA as the recognition unit, demonstrated a remarkably low detection limit (i.e., 1.40 nM) and a rapid response time (10 s) for triphosgene. By comparison, BOPD, featuring an OPD unit, showed superior selectivity towards triphosgene, with a detection limit of 93 nM and a response time of up to 30 s. A portable sensing platform was developed by loading BOPD onto test strips made of TLC plates, nonwoven materials and small-headed cotton swabs, which were assessed for their effectiveness in detecting phosgene. We additionally performed the first successful application of a fluorescent probe, namely BOPD, for monitoring the accumulation of phosgene in plants
Dynamic Frequent Subgraph Mining Algorithms Over Evolving Graphs: a Survey
No full textFrequent subgraph mining (FSM) is an essential and challenging graph mining task used in several applications of the modern data science. Some of the FSM algorithms have the objective of finding all frequent subgraphs whereas some of the algorithms focus on discovering frequent subgraphs approximately. On the other hand, modern applications employ evolving graphs where the increments are small graphs or stream of nodes and edges. In such cases, FSM task becomes more challenging due to growing data size and complexity of the base algorithms. Recently we see frequent subgraph mining algorithms designed for dynamic graph data. However, there is no comparative review of the dynamic subgraph mining algorithms focusing on the discovery of frequent subgraphs over evolving graph data. This article focuses on the characteristics of dynamic frequent subgraph mining algorithms over evolving graphs. We first introduce and compare dynamic frequent subgraph mining algorithms; trying to highlight their attributes as increment type, graph type, graph representation, internal data structure, algorithmic approach, programming approach, base algorithm and output type. Secondly, we introduce and compare the approximate frequent subgraph mining algorithms for dynamic graphs with additional attributes as their sampling strategy, data in the sample, statistical guarantees on the sample and their main objective. Finally, we highlight research opportunities in this specific domain from our perspective. Overall, we aim to introduce the research area of frequent subgraph mining over evolving graphs with the hope that this can serve as a reference and inspiration for the researchers of the field. © (2024), (PeerJ Inc.). All rights reserved
Liquid Metal-Controlled Dual-Band Doppler Radar for Enhanced Velocity Measurement
No full textDoppler radars, which are critical instruments for velocity measurement, may need to be reconfigured to adapt to different environmental conditions or for ease of use. However, conventional electrical, optical, and physical reconfiguration methods often come with several disadvantages such as deteriorated radiation pattern, reduced radiation efficiency, and high cost. Therefore, the aim of this article is to integrate microwave components that can be controlled using liquid metal (LM) displacement into a Doppler radar to adjust its main lobe direction and operating frequency to the desired values and enhance the measurement capacity of the respective radar. Through this study, multiple parameters of an operational Doppler radar have been simultaneously adjusted using LM displacement exploitation for the first time, thus avoiding the shortcomings associated with conventional reconfiguration methods. To achieve this objective, initially, a back-to-back Vivaldi antenna operating at 2.45 GHz is designed, and beam switching ability is imparted to the structure using the LM displacement method. Subsequently, various techniques are used to convert the structure into a dual-band antenna capable of simultaneous operation at 2.45 and 5.8 GHz, ensuring the desired beam switching feature at both the frequencies. In addition, a power divider capable of switching between the two operating frequencies through LM assistance is proposed, and its integration into the radar system enables the control of both main lobe direction and frequency using the proposed method
Comparison of Magnetic Seed and Rfid Methods in the Localization of Non-Palpable Breast Lesions
No full textBackground: Many methods have been developed for localizing non-palpable breast lesions. This study investigated the success rate and surgical results of the magnetic seed (Magseed) and radiofrequency identification (RFID) method, which are relatively new compared to standard wire-guided localizations. Materials and Methods: 20 simulation (10 Magseed, 10 RFID) models were created using turkey breasts and raisins. Raisins containing magnetic seed and RFID tags were placed on the turkey breast. Sentimag (R) probe was used for the Magseed group, and Faxitron LOCalizer (TM) System device was used in the RFID group. Both methods were evaluated in terms of accuracy in detecting breast lesion localization, operation times, excised tissue weights, total resection volume, surgical margin negativity, and re-excision rates. Results: Lesion localization success in both techniques was 100%. While procedure times were statistically significantly shorter in the Magseed group, incision lengths were shorter in the RFID group (P = 0.013, P = 0.007, respectively). No statistically significant difference was found between the groups for the weight of the removed parts, total resection volume, and surgical margin distance (P > 0.05). Conclusion: In this feasibility study, it was concluded that neither the RFID nor Magseed methods had a significant advantage over each other, in terms of localization detection and surgical margin negativity, and both methods could be used successfully for localization
Evaluation of Land Surface Temperature Within the Framework of Urban Sprawl: a Case Study in İzmi̇r, Seferihisar
No full textKentleşme oranı geçmişten günümüze kadar artarak gelmesine karşın, kentsel alanlardaki gelişme sınırlı olması nedeniyle, artan nüfusun kentsel hizmet ve arazi ihtiyacının karşılanabilmesi için çeperlerde yeni yapılaşma alanlarının açılması yönünde baskı oluşmaya başlamış ve kentler yayılmaya başlamıştır. Bu yayılma sonucunda arazi örtüsünde meydana gelen değişiklikler çeşitli sorunlara neden olduğundan, kentsel yayılma küresel bir sorun haline gelmiştir. Doğal alanların, kentsel mekânlar oluşturmak üzere tahrip edilmesi iklim değişikliği etkilerinin de giderek artması anlamına gelmektedir. Kentsel alanlarda iklim değişikliği etkileri (yağmur suyu birikimi, kentsel ısı adası oluşumu vb.) daha fazla hissedilmektedir. Bu tez çalışmasında kentsel yayılma sonucunda meydana gelen arazi örtüsü değişimlerinin arazi yüzey sıcaklığı (AYS) üzerindeki etkilerine odaklanılmıştır. Kentsel yayılmayı gözlemlemek ve arazi örtüsündeki değişimlerin AYS üzerindeki etkileri belirlemek amacıyla yapılan bu çalışmada, uzaktan algılama verileri kullanılarak Seferihisar ilçesinin 2017 ve 2023 yılları arasındaki her bir yıl için analizler yapılmıştır. Analizlerin veri seti; Landsat 8 uydusundan ve NASA'dan elde edilen SRTM uzaktan algılama verilerinden oluşmaktadır. Bu veriler görüntü işleme, rastgele orman algoritması ve denetimli öğrenme yöntemleri ile spektral endeksler (NDVI, NDBI, MNDWI, NDBaI), arazi örtüsü sınıflandırması ve AYS haritaları oluşturulmuştur. Ardından 2017-2023 arazi örtüsü değişim haritası kullanılarak, Seferihisar ilçesinin 2030 yılı arazi örtüsü tahmini yapılmıştır. Analiz sonuçlarına göre çalışma alanında arazi örtüsünde gözle görünür biçimde değişiklik yaşanmıştır. Bu değişiklikler sonucunda yapılaşmış alanların ve çıplak arazilerin AYS üzerinde artırıcı bir etkisi olduğu, bitki örtüsü ile kaplı olan alanların ise azaltıcı etkisi olduğu anlaşılmıştır. Bitki örtüsünün yer yer iyileştiği ve arttığı alanlarda AYS değerlerinde azalma meydana gelmesi, yapılaşmış alanların ve çıplak arazilerin artış gösterdiği alanlarda ise AYS değerlerinin artış meydana gelmesi çalışmanın önemli bulgularındandır. Bu bulgular doğrultusunda çalışmada 2030 yılında karşılaşılabilecek riskler değerlendirilmiştir.The creation of spaces that meet the needs of an increasing population, developing economy, and rising levels of human well-being is leading to the intensification, expansion, and sprawl of urban areas. As a result of this sprawl, changes in land cover have caused various issues, making urban sprawl a global problem. The transformation of natural areas into urban spaces exacerbates the impacts of climate change. The effects of climate change, such as stormwater accumulation and Urban Heath Island (UHI) formation, are more pronounced in urban areas. This thesis focuses on the effects of land cover changes resulting from urban sprawl on Land Surface Temperature (LST). To observe urban sprawl and determine its impact on LST, this study utilizes remote sensing data to analyse Seferihisar district for each year between 2017 and 2023. The dataset includes remote sensing data from Landsat 8 and SRTM obtained from the NASA. These data were used to create spectral indices (NDVI, NDBI, MNDWI, NDBaI), land cover classification, and LST maps through image processing, random forest algorithm, and supervised learning methods. Subsequently, a land cover prediction for Seferihisar district for the year 2030 was made using the 2017-2023 land cover change map. The analysis findings indicate noticeable changes in land cover within the study area. These changes reveal that built-up areas and bare lands have an increasing effect on LST, while vegetated areas have a decreasing effect. A significant finding of the study is the reduction in LST values in areas where vegetation has improved and increased, and the rise in LST values in areas where built-up areas and bare lands have expanded. Based on these findings, potential risks for the year 2030 were evaluated
A Mixed-Integer Dynamic and Stochastic Algae Process Optimization
No full textWith increased energy demand as it gets scarcer, a great deal of research is being carried out into alternatives to non - renewable energy resources. One of the promising studies is the biofuel production from micro algae. Microalgae are photosynthetic organisms and capture carbon dioxide, reducing emissions and providing valuable products (fuel, fertilizer, etc.). Thus, efficiency in the design and optimization of process related units are important. In this study, the optimal experimental conditions for Nannochloropsis Oculata were calculated under the constraints of the model equations and other process related constraints through simultaneous optimization approach. The economic evaluation of the process is also handled by introducing the uncertainty in the economic measures sampled from normal distribution to maximize the average profit. Unlike traditional approaches, the MINLP formulation, which is solved stochastically, dynamically, and simultaneously, provides more robust and reliable results, flexibility, improved decision making, reduced risks to be taken and a better understanding of risk factors. Copyright (C) 2024 The Authors. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/