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Prediction of landslide tsunami run-up on a plane beach through feature selected MLP-based model
No full textWe proposed new prediction models based on multilayer perceptron (MLP) which successfully predict the maximum run-up of landslide -generated tsunami waves and assess the role of parameters affecting it. The input is approximately 55,0 0 0 rows of data generated through an analytical solution employing slide's cross section, initial submergence, vertical thickness, horizontal length, beach slope angle and the maximum run-up itself, along with its occurrence time. The parameters are first ranked through a feature selection algorithm and six models are constructed for a 9,0 0 0 -row randomly sampled dataset. These MLP-based models led predictions with a minimum Mean Absolute Percentage Error of 1.1% and revealed that vertical slide thickness has the largest impact on the maximum tsunami run-up, whereas beach slope angle has minimal effect. Com parison with existing literature showed the reliability and applicability of the offered models. The methodology introduced here can be suggested as fast and flexible method for prediction of landslide -induced tsunami run-up. (c) 2022 Shanghai Jiaotong University. Published by Elsevier B.V. This is an open access article under the CC BY -NC -ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/
Anatolian Tigers: A Miracle or a Myth? A Regional Political Economic Analysis
No full textIn this study, I examine the potential of the Anatolian Tigers, which are an important engine for the Turkish economy, in a very novel framework. I also compare the role of Anatolian Tigers with Istanbul-based firms within the capitalist classes. The study explores that the Anatolian Tigers have significant potential for exports, foreign direct investment and long-term sales, but are lagging behind in foreign direct investment. The findings of the study may be the first study to shed light on the development potential of the Anatolian Tigers by addressing issues that have not yet been addressed in the literature on the Anatolian Tigers
UAV Trajectory Optimization for Maximum Soaring in Windy Environment
No full textOptimal trajectory planning in a windy environment is a complex problem when airplane performance characteristics are considered. This paper introduces a novel form of Legendre pseudospectral optimization to solve boundary value problems in UAV trajectory planning. The proposed architecture applies Legendre-Gauss-Lobatto and Hamilton-Jacobi-Bellman equations to generate candidate pieces of trajectories with respect to the UAV dynamic constraints. Analytical performance-based solutions are also developed for sample cases to achieve an optimal criterion in trajectory planning. Moreover, the notion of wind soaring is exploited to use the beneficial effects of tailwind velocities in trajectory planning. Integral cost functions are handled by Gauss-type quadrature rules. Simulations demonstrate the efficiency of the pseudospectral method compared with other solvers, in eliminating the difficulties of boundary value problems by employing the boundary points in the interpolation equation. The effectiveness of the proposed approach is demonstrated through dynamic simulations
DEPREM DİRENÇLİ KENTLER İÇİN BELEDİYELERDE YENİDEN YAPILANMA
No full textDoğal afet olarak tanımladığımız deprem, sel, heyelan ve yangınların dünya kentleri üzerindeki tahrip edici etkisi her geçen yıl artmaktadır. Esasında kentler, sosyal, ekonomik, fiziksel ve çevresel boyutlarıyla karmaşık yapılar olduklarından, onlar için tehdit oluşturan afetler, terör saldırıları, finansal krizler, gıda güvenliği, enerji krizleri ve siyasal istikrarsızlıklar gibi riskler kentleri tehdit etmektedir. Kentlerin, gelecek herhangi bir zamanda, sosyal, ekonomik ve teknik sistemleriyle altyapısını etkileyebilecek nitelikte yaşanabileceği şok ve sorunlara karşı yapı, işlev, sistem ve kimliğini koruyabilmesi ancak olası risklere karşı direnç kapasitesini artırmasıyla mümkündür. Bu araştırmada depremlerin kentlerdeki yıkıcılığının azaltılması için genelde yerel yönetimler özelde ise belediye yönetimlerinde yeniden yapılanma gerekliliği tartışmaya açılmıştır. Türkiye’de yaşanan çok sayıda deprem kentleri tahrip etmiş fakat ne yazık ki, yapıların deprem koşulları göz önüne alınarak tasarlanması ve inşa edilmesi gerekliliği uzun yıllar boyunca anlaşılamamıştır. Ayrıca, belediyelerin kentsel alanlardaki arazi planlaması, doğal afetlerden kaynaklanan riskleri azaltmak için önemli bir araç olmasına rağmen gerektiği şekilde kullanılamamıştır. Araştırmanın amacı, kentlerde yetkili ve görevli seçilmişlerin şahsi menfaatlerini “mahalli müşterek ihtiyaçların” üstünde görmelerini engelleyecek bir sistemin oluşması için tartışma başlatmaktır. Araştırmada dirençli kentlerin inşa edilebilmesi için belediye organlarının yeniden yapılanması önerilerek başta belediye başkanının seçilme tarzı tartışmaya açılmış, güçlü tek adamlık modeli yerine, profesyonel yöneticili meclis sistemi ve kent komisyonu modeli önerilmiştir. Belediye meclisi ve ihtisas komisyonları için de meslek kriteri belirlenmesi önerilmiştir. Araştırmada nitel veri toplama teknikleri kullanılmıştır
Antioxidant Capacity, Sugar Content, and Tandem HPLC-DAD-ESI/MS Profiling of Phenolic Compounds from Aronia melanocarpa Fruits and Leaves (Nero and Viking Cultivars)
No full textThis study examined the phenolic profile, sugar composition, and antioxidant capacities of chokeberry fruits and leaves obtained from four different Turkiye provinces. A total of 21 phenolics including phenolic acid and its derivatives, flavanols, anthocyanins, and flavonols were determined in the fruits, while the leaves had 19 phenolics, including phenolic acid and its derivatives, flavanols, and flavonols. The total amount of phenolic compounds was the highest in both fruits and leaves in the samples from the Bursa province. Cis 5-O-p-coumaroylquinic acid and secoxyloganin were quantified for the first time in both fruits and leaves. In summary, it was found that different geographical locations significantly affected the phenolics, sugar contents, and antioxidant activities of the fruits and leaves.The authors are grateful to the support from the Ministry of Higher Education and Scientific Research Tunisia (Program contract LR14ES08) [LR14ES08]; Ministry of Higher Education and Scientific Research TunisiaThe authors are grateful to the support from the Ministry of Higher Education and Scientific Research Tunisia (Program contract LR14ES08). We wish to thank Dr. Muharrem Keskin from Mustafa Kemal University, Hatay, Turkey, for his outstanding editing and proof reading the article
Teknik göstergelerle derin öğrenme modelleri kullanarak hisse senedi fiyatı tahmini
No full textLisansüstü Eğitim Enstitüsü, Endüstri Mühendisliği Ana Bilim Dalı, Endüstri Bilim DalıHisse senedi fiyatlarının doğru tahmini, yatırımcıların ne zaman ve nereye yatırım yapacaklarına dair kararlarını destekler. Ancak, hisse senedi piyasasının dinamik, doğrusal olmayan, karmaşık ve kaotik doğası, fiyat tahminini zorlaştırır. Piyasa hareketleri, siyasi olaylar, firma politikaları, ekonomik koşullar, emtia fiyatları ve banka kurları gibi birçok makroekonomik faktörden etkilenir. Ayrıca gelişen teknoloji ve iletişim sistemleri, bu olayların hızla işlenmesine olanak tanıyarak hisse senedi fiyatlarının hızlı dalgalanmasına neden olur. Dolayısıyla bankalar, finans kurumları ve büyük yatırımcılar, hızlı alım satım yapmak zorunda kalır ve piyasanın karmaşıklığı kesin tahmin yapmayı daha da zorlaştırır. Hisse senedi fiyatlarının doğru tahmini için yeni ve etkili yöntemlerin geliştirilmesi gerekmektedir. Bu çalışmada, Yahoo Finance gibi internet sitelerinden elde edilen veriler teknik göstergeler kullanılarak hisse senedi fiyatlarının tahmin edilmesi amaçlanmıştır. Ham verilerdeki gürültüyü azaltmak, anlamlı sonuçlar elde etmek ve tahmin doğruluğunu artırmak amacıyla teknik indikatörler için korelasyon katsayısı yöntemi kullanılmıştır. Yapay Sinir Ağları (YSA) modelleri, finansal zaman serisi verilerinin analizinde büyük bir etkinlik sağlamaktadır. YSA ile yapılacak tahminler için en uygun parametreler seçilmiştir. Veri ön işleme sürecinden sonra, Tek Katmanlı Uzun Kısa Süreli Hafıza (LSTM), 3 Katmanlı LSTM, 3 Katmanlı Çift Yönlü Uzun Kısa Süreli Hafıza (BiLSTM) ve hibrit Evrişimli Sinir Ağı- Uzun Kısa Süreli Hafıza (CNN-LSTM); yöntemleri uygulanmıştır. Bu model ile, gerçeğe yakın fiyat tahminlerinin bulunmasının yanısıra, teknik indikatörler aracılığıyla hisse senedi fiyatı tahminini etkileyen özellikleri azaltmak amaçlanmıştır. Sonuçlar, derin öğrenme (DL) teknikleri arasında Tek Katmanlı LSTM yönteminin diğer yöntemlere göre daha gerçekçi tahminler sunduğunu ortaya koymuştur.Accurate stock price prediction is crucial for supporting investors' decisions regarding the timing and allocation of investments. However, the dynamic, non-linear, complex, and chaotic nature of the stock market makes price prediction a challenging task. Market movements are influenced by various macroeconomic factors, such as political events, corporate policies, economic conditions, commodity prices, and bank rates. Furthermore, advancements in technology and communication systems enable these events to be processed rapidly, leading to swift fluctuations in stock prices. Consequently, banks, financial institutions, and large investors are compelled to make quick buy and sell decisions, further complicating precise predictions. Therefore, there is a pressing need for the development of new and effective methods for accurate stock price predictions. This study aims to predict stock prices using technical indicators obtained from sources like Yahoo Finance. To reduce the noise in raw data, obtain meaningful results and increase the estimation accuracy, correlation coefficient method was used for technical indicators. Artificial Neural Networks (ANN) models provide great efficiency in the analysis of financial time series data. The most appropriate parameters were selected for the estimations to be made with ANN. After the data preprocessing process, Single Layer Long Short Term Memory (LSTM), 3 Layer LSTM, 3 Layer Bidirectional Long Short Term Memory (BiLSTM) and Hybrid Convolutional Neural Network-Long Short Term Memory (CNN-LSTM); methods were applied. With this model, in addition to finding realistic price estimations, it was aimed to reduce the features affecting stock price estimation through technical indicators. The results showed that the Single Layer LSTM method provides more realistic estimations compared to other methods among deep learning (DL) techniques
Obtaining xylitol by catalytic hydrogenation of xylose in thepresence of raney nickel catalyst
No full textLisansüstü Eğitim Enstitüsü, Gıda Mühendisliği Ana Bilim DalıKsilitol, düşük kalorili ve beş karbonlu bir tatlandırıcıdır. Düşük glisemik indeksi (GI), diş çürümesine neden olmaması ve ağızda oluşturduğu ferahlık etkisiyle sakız ve şekerleme başta olmak üzere birçok gıda uygulamasında kullanılan bir polioldür. Ksilitol üretiminde en yaygın yöntemlerden biri ksilozun katalitik hidrojenasyonudur. Bir pentoz şekeri (5 C'lu şeker) olan ksiloz ise biyokütle kaynaklarında bulunan hemiselüloz içeriğinden üretilir. Tez çalışmasında ksiloz hammaddesi kullanılarak basınçlı reaktörde ksilitol üretim verimi 1 litrelik laboratuvar tipindeki basınçlı reaktör ve gaz kontrol sistemiyle takip edilmiştir. Basınç, sıcaklık, katalist miktarı ve hammadde konsantrasyonuna göre reaksiyon verimi incelenmiştir. Değerlendirmeler sonucunda elde edilen verilere göre katalizör olarak kullanılan raney nikel miktarı ksilitol dönüşümüne en fazla etki eden parametredir. Belirlenen parametre aralıklarına göre incelendiğinde optimum ksilitol üretim koşullarının; 40 bar hidrojen basıncı, %25 ksiloz konsantrasyonu, 40 g Raney nikel katalist ve 140°C sıcaklıkta elde edildiği, buna göre ksilitol üretiminin %86.6±0.2 ve ksiloz dönüşümünün %98.35±0.2 olduğu saptanmıştır. Bu tez çalışmasında ksilitol verimine etki eden bir diğer parametrenin ise karıştırma hızı olduğu tespit edilmiştir. Karıştırma hızının 400 rpm'den 800 rpm'e yükseltilmesi ile reaksiyonun daha hızlı gerçekleştiği ve reaksiyon süresinin kısaldığı, ksilitol veriminin de %98'e ulaştığı HPLC analizi ile belirlenmiştir.Xylitol is a low-calorie, five-carbon sweetener. It is a polyol used in various food applications, primarily in gum and confectionery, due to its low glycemic index (GI), non-cariogenic properties, and refreshing effect in the mouth. One of the most common methods for xylitol production is the catalytic hydrogenation of xylose. Xylose, a pentose sugar (5-carbon sugar), is derived from the hemicellulose content of biomass sources. In this thesis, xylitol production yield was monitored using a 1-liter laboratory-scale pressurized reactor and gas control system with xylose as the raw material. The reaction yield was examined concerning pressure, temperature, catalyst amount, and raw material concentration. Based on the evaluation results, it was found that the amount of Raney nickel used as the catalyst was the most influential parameter on xylitol conversion. Within the specified parameter ranges, the optimum conditions for xylitol production were determined to be 40 bar hydrogen pressure, 25%xylose concentration, 40 g catalyst, and a temperature of 140°C. Under these conditions, xylitol production was 86.6±0.2% and xylose conversion was found to be 98.35±0.2%. In the thesis study, it was determined that another parameter affecting the xylitol yield was the stirring speed. It was determined by HPLC analysis that increasing the reaction speed from 400 rpm to 800 rpm shortened the reaction time and the xylitol yield reached 98
Antioxidant, cytotoxic, anti-migratory, and pro-apoptotic effects of Bolanthus turcicus extracts on head and neck cancer cells
No full textPurpose Investigation of various plant extracts using in-vitro/in-vivo assays has emerged as a promising avenue for identifying potential pharmacophores that can be developed into therapeutic drugs. This study aims to assess the bioactive compounds and antioxidant capacity of the Bolanthus turcicus (B. turcicus) and to investigate the effects on head and neck cancer (HNC) cell lines. Methods Methanol (MeOH), ethyl acetate (EA) and aqueous (Aq) extracts were prepared from B. turcicus, and the amount of total phenolic content (TPC) and total flavonoid content (TFC) in the extracts were analyzed by the Folin-Ciocalteu and Aluminum chloride method, respectively. In addition, the total antioxidant capacity and iron reducing potential of B. turcicus extracts were determined by the Phosphomolybdenum and Ferric ion reducing antioxidant power (FRAP) method. The effect of B. turcicus on HEp-2, SCC-90, SCC-9, FaDu HNC cell viability, motility, and cell-nuclear morphology was evaluated by MTT, scratch-wound healing assay, and Pllalloidin-DAPI staining, respectively. The effect of B. turcicus on the expression of CASP-3, BAX, and BCL-2 genes at the mRNA, protein, and intracellular level was evaluated by quantitative PCR (qPCR), western blot, and immunofluorescence staining. Moreover, Annexin V-FITC/PI, was used in flow cytometry to investigate the effect of B. turcicus on apoptosis. Results The MeOH extract exhibited the highest phenolic content, flavonoid content and antioxidant activity (p < 0.05 for all). HNC cells treated with extracts indicated delayed wound healing and decreased motility (p < 0.05 for all). Analysis of annexin V-PI staining indicated that the B. turcicus extracts induced apoptosis but not viability and necrosis in the HNC cell (p < 0.05 for all). Moreover, qPCR data regarding the apoptotic mechanism showed that the extracts could induce apoptosis by upregulation of pro-apoptotic CASP-3 and BAX genes and downregulation of anti-apoptotic BCL-2 gene (p < 0.05 for all). The expression of protein and intracellular levels of CASP-3 and BAX were increased, while the BCL-2 was decreased in cells treated with the extracts (p < 0.05 for all). In addition, diffuse pycnosis and DNA condensation in HNC cell nuclei, confirming apoptotic cell death (p < 0.05 for all). Conclusion This study data indicated that B. turcicus extracts have antioxidant, cytotoxic, anti-migratory and pro-apoptotic activity. In conclusion, it has been shown that B. turcicus can be used as a potential therapeutic agent against HNC.Scientific and Technological Research Council of Turkey (TUBITAK) [120Z967]This work was supported by Scientific and Technological Research Council of Turkey (TUBITAK) (Grant Number: 120Z967 | Recipient: Sibel OZDAS, PhD
An experimental investigation on the flow control of the partially stepped NACA0012 airfoil at low Reynolds numbers
No full textAn experimental study of flow control around a NACA0012 airfoil modified with fully and partially step geometry was conducted at Reynolds numbers of 6 x 104 and 1.2 x 105. Partially step geometries, the location of the step on the airfoil, and Reynolds number are varied to show their effect on aerodynamic performance and flow structures on the airfoil. Experimental results show that fully and partially step geometries are effective for flow control around the airfoil and aerodynamic performance enhancement. The maximum increase in lift coefficient is approximately 46%, and the stall angle is shifted about 1 degrees by the SM4 model at Re of 6x104 while the step geometry is on the pressure side. For a Reynolds number of 1.2 x 105, the highest increase in the lift-to-drag ratio of the airfoil is observed about 17.1 at an angle of attack of 6 degrees by the SM2 model when step geometry is placed on the pressure side of the airfoil. In the event of partially or fully stepped at the pressure side of the model, step flow structures, including the reattachment line, recirculation zone, and corner eddy, are obtained. However, even though the step geometry is at the suction surface of the model, the formation of a laminar to turbulent transition is observed. The overall results suggest that the partially stepped geometry length, Reynolds number, and step location side on the airfoil have an important role in flow control to improve aerodynamic performance for various angles of attack
Why the Perfectly Symmetric Cobalt-Pentapyridyl Loses the H2 Production Challenge: Theoretical Insight into Reaction Mechanism and Reduction Free Energies
No full textResearchers have extensively investigated photo-catalytic water reduction utilizing Cobalt-based catalysts with polypyridyl ligands. While catalysts exhibiting distorted polypyridyl ligand demonstrate higher H-2 production yields, those with ideal octahedral coordination display poor performance. This outcome suggests the crucial role of ligand framework in catalytic activity, yet reasons behind the disparity in H-2 production rates for catalysts with octahedral geometries remain unclear. We theoretically examined the water reduction mechanism of Co-based poly-pyridyl catalyst, CoPy5, having perfect octahedral coordination. We clarified the effect of octahedral coordination by utilizing each intermediate step of ECEC mechanism. We determined spin states, solvent response, electronic structures, and reduction free energies. CoPy5 with perfect octahedral coordination, alongside its distorted counterparts, exhibit similar spin states as the reaction progresses through each intermediate step. However, the first reduction free energy obtained for the CoPy5 is slightly higher than that of its distorted counterparts. Following the second protonation, resulting H-2 molecule experiences limited diffusion from the Co center due to the compact structure of the CoPy5, which blocks the Co center for the next H-2 production cycle. Catalysts having distorted octahedral geometries facilitate fast removal of H-2 into the solvent. Thus, the reaction center becomes immediately available for subsequent H-2 production.Y. G. acknowledges the Scientific and Technological Research Council of Turkiye (TUBITAK). This study has received funding from the TUBITAK under the 3501 Career Development Program (grant agreement No: 120Z240). The calculations reported in this p; Scientific and Technological Research Council of Turkiye (TUBITAK) [120Z240]; TUBITAKY. G. acknowledges the Scientific and Technological Research Council of Turkiye (TUBITAK). This study has received funding from the TUBITAK under the 3501 Career Development Program (grant agreement No: 120Z240). The calculations reported in this paper were performed at the TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRUBA), based in Turkiye