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Article Citation - WoS: 1Citation - Scopus: 1Spline Based Sparseness and Smoothness for Partially Nonlinear Model Via C-Fused Lasso(American Institute of Mathematical Sciences, 2025) Taylan, P.; Yerlikaya-¨Ozkurt, F.; Tez, M.; Yerlikaya-Ozkurt, FatmaOne of the most beneficial and widely used models for data analysis are partially nonlinear models (PNLRM), which consists of parametric and nonparametric components. Since the model includes the coefficients of both the parametric and nonparametric parts, the complexity of the model will be high and its interpretation will be very difficult. In this study, we propose a procedure that not only achieves sparseness, but also smoothness for PNLRM to obtain a simpler model that better explains the relationship between the response and covariates. Thus, the fused Lasso problem is taken into account where nonparametric components are expressed as a spline basis function, and then the Fused Lasso estimation problem is built and expressed in terms of conic quadratic programming. Applications are conducted to evaluate the performance of the proposed method by considering commonly utilized measures. Promising results are obtained, especially in the data with nonlinearly correlated variables. © (2025), (American Institute of Mathematical Sciences). All rights reserved.Article Eski Köye Yeni Adet: Hukuk ve Edebiyat Çalışmaları(Hukuk Kuramı, 2017) Şimşek, A. AslıÖncelikle başlıkta geçen “eski köye yeni adet”in ne olduğundan bahsetmek uygun olacaktır. Hukuk; hem bir kurallar sistemi olarak kadim zamanlardan, hem de ülkemiz özelinde toplumsal düzeni biçimlendirici bir mekanizma olarak Türk modernleşmesinin başından beri kullanılan bir argüman olmuştur. Hukukun eski köy olması bir parça buradan gelmektedir. Konumuz itibariyle, hukuk eğitimine ilişkin tartışmaya açılmış birçok unsurun ise eski köyün sakinleri olduğu görülmektedir. Bunların başında hukuku hukukla açıklama, pozitif hukuk metinleri üzerinden dersleri yürütme ve fakat o hukuk kuralının hangi toplumsallığa işaret ettiğine değinmeme gibi teknik ve pozitivist bir yöntemin benimsenmiş olması gelmektedir. Bunlara derslerin kalabalık amfilerde konferans şeklinde işlenmesi, ders programlarının yenilenmemesi, derslerin üzerine kurulu olduğu pozitif hukuk metinleri ve onları açıklayan ders kitapları yerine öğrencinin sadece satın aldığı fotokopilerden çalışarak dersi geçme notu almaya yönelmesi eklemlenmektedir. Böylece diğer disiplinlere ve sosyal bilimlere kendini büyük ölçüde kapatan hukuk eğitimi muhafazakarlaşmakta ve adeta böyle gelmiş böyle giden bir eski köy düzeni sürmektedir.Article Citation - WoS: 44Citation - Scopus: 51On the lifetime behavior of a discrete time shock model(Elsevier, 2013) Eryilmaz, SerkanIn this article, we study a shock model in which the shocks occur according to a binomial process, i.e. the interarrival times between successive shocks follow a geometric distribution with mean 1/p. According to the model, the system fails when the time between two consecutive shocks is less than a prespecified level. This is the discrete time version of the so-called delta-shock model which has been previously studied for the continuous case. We obtain the probability mass function and probability generating function of the system's lifetime. We also present an extension of the results to the case where the shock occurrences are dependent in a Markovian fashion. (C) 2012 Elsevier B.V. All rights reserved.Article Citation - WoS: 11Citation - Scopus: 14A Neural Network Model for the Assessment of Partners' Performance in Virtual Enterprises(Springer London Ltd, 2007) Sari, Burak; Amaitik, Saleh; Kilic, S. EnginIn response to increasing international competition, enterprises have been investigating new ways of cooperating with each other to cope with today's unpredictable market behaviour. Advanced developments in information & communication technology (ICT) enabled reliable and fast cooperation to support real-time alliances. In this context, the virtual enterprise (VE) represents an appropriate cooperation alternative and competitive advantage for the enterprises. VE is a temporary network of independent companies or enterprises that can quickly bring together a set of core competencies to take advantage of market opportunity. In this emerging business model of VE, the key to enhancing the quality of decision making in the partner companies' performance evaluation function is to take advantage of the powerful computer-related concepts, tools and technique that have become available in the last few years. This paper attempts to introduce a neural network model, which is able to contribute to the extrapolation of the probable outcomes based on available pattern of events in a virtual enterprise. Quality, delivery and progress were selected as determinant factors effecting the performance assessment. Considering the features of partner performance assessment and neural network models, a back-propagation neural network that includes a two hidden layers was used to evaluate the partner performance.Article Citation - WoS: 39Citation - Scopus: 37MoS2-nanosheet/graphene-oxide composite hole injection layer in organic light-emitting diodes(Korean inst Metals Materials, 2017) Park, Minjoon; Thang Phan Nguyen; Choi, Kyoung Soon; Park, Jongee; Ozturk, Abdullah; Kim, Soo Young; Nguyen, Thang PhanIn this work, composite layers comprising two-dimensional MoS2 and graphene oxide (GO) were employed as hole injection layers (HILs) in organic light-emitting diodes (OLEDs). MoS2 was fabricated by the butyllithium (BuLi) intercalation method, while GO was synthesized by a modified Hummers method. The X-ray diffraction patterns showed that the intensity of the MoS2 (002) peak at 14.15A degrees decreased with increase in GO content; the GO (001) peak was observed at 10.07A degrees. In the C 1s synchrotron radiation photoemission spectra, the contributions of the C-O, C=O, and O-C=O components increased with increase in GO content. These results indicated that GO was well mixed with MoS2. The lateral size of MoS2 spanned from a few hundreds of nanometers to 1 mu m, while the size of GO was between 400 nm and a few micrometers. Thus, the coverage of the MoS2-GO composite on the ITO surface improved as the GO content increased, owing to the large particle size of GO. Notably, GO with large size could fully cover the indium tin oxide film surface, thus, lowering the roughness. The highest maximum power efficiency (PEmax) was exhibited by the OLED with MoS2-GO 6:4 composite HIL, indicating that similar contents of MoS2 and GO in MoS2-GO composites provide the best results. The OLED with GO HIL showed very high PEmax (4.94 lm W-1) because of very high surface coverage and high work function of GO. These results indicate that the MoS2-GO composites can be used to fabricate HILs in OLEDs.Article Citation - WoS: 10Citation - Scopus: 10Temperature Effects on Optical Characteristics of Cdse Thin Films(Elsevier Sci Ltd, 2021) Gullu, H. H.; Isik, M.; Surucu, O.; Gasanly, N. M.; Parlak, M.CdSe is one of the significant members of II-VI type semiconducting family and it has a wide range of technological applications in which optoelectronic devices take a special position. The present paper reports the structural and optical characteristics of thermally evaporated CdSe thin films. XRD pattern exhibited preferential orientation along (111) plane while atomic composition analyses resulted in the ratio of Cd/Se as closer to 1.0. Temperature-dependent band gap characteristics of CdSe thin films were investigated for the first time by carrying out transmission experiments in the 10-300 K range. The analyses showed that direct band gap energy of the compound decreases from 1.750 (at 10 K) to 1.705 eV (at 300 K). Varshni model was successfully applied to the temperature-band gap energy dependency and various optical constants were determined. Raman spectrum of CdSe thin films was also presented to understand the vibrational characteristics of the compound. The present paper would provide worthwhile data to researchers especially studying on optoelectronic device applications of CdSe thin films.Article Görüntülerden Bilgi Elde Etmek İçin Görüntü Açıklama Çalışmalarının Sistematik Haritalandırma İncelemesi(2020) Sezen, Arda; Turhan, ÇiğdemÇeşitli görüntü türlerinden görüntü meta verilerini elde etmeyi, işlemeyi ve anlamlı sonuçlar çıkarmayı amaçlayan görüntü açıklaması kavramı, bilgi toplumunda görüntülerden bilgi edinme konusunda daha kritik hale gelmiştir. Bu konuda literatürde önerilen birçok yaklaşım vardır, ancak en uygun olanı seçmek kolay değildir. Bu çalışmada, görüntü açıklamalarındaki kilit yaklaşımlar, kapsamlı bir literatür taraması ve sistematik haritalama yoluyla incelenmiştir. Çalışmamızın yeniliği, literatürdeki görüntü açıklama çalışmalarını araştırmak, haritalamak ve analiz etmek ve seçilen çalışmaları sınıflandırmak, araştırma boşluklarını ortaya çıkarmak ve bu makalede sunulan araştırma soruları için görsel özet hazırlamak adına ilk denemeyi temsil etmesidir. Literatürde, ilgi alanını farklı açılardan araştırmak için sistematik haritalama yaklaşımı önerilmektedir. Bu amaçla, tespit edilen toplam 404 çalışma içerisinden 95 çalışma seçilmiştir. Alandaki literatürün incelenmesi, mevcut yöntemlerin / tekniklerin, araçların, metriklerin, süreçlerin veya diğer teknik yaklaşımların kendi başlarına eksiksiz bir çözüm üretmek için yeterli olmadığını göstermektedir. Önerilen teknikleri birleştirerek ve disiplinlerarası yaklaşımları dikkate alarak yeni çözümler üretmenin gerekliliği de önerilmiştir.Article Citation - WoS: 14Citation - Scopus: 17NEW EDOT CONTAINING POLYMERS: EFFECT OF RING SIZE ON THE BENZIMIDAZOLE ACCEPTOR(Pergamon-elsevier Science Ltd, 2016) Cansu-Ergun, E. G.; Onal, A. M.; Cihaner, A.In this study, three different benzimidazole (BIm) based acceptor groups bearing cyclohexane, cycloheptane and cyclooctane rings at 2-C position of benzimidazole were synthesized and coupled with ethylenedioxythiophene (EDOT) donor units via Stille cross-coupling reaction. The resulting donor acceptor-donor (DAD) type monomers were examined in terms of their electrochemical and optical behaviors. All three monomers exhibited dual absorption bands due to their donor-acceptor pattern and exhibited one irreversible oxidation peak at about 0.80 V. The monomers were electrochemically polymerized via both potentiostatic and potentiodynamic methods and electro-optical properties of obtained conjugated polymer films were investigated in monomer free electrolytic solution. It was found that the polymer films exhibited quasi-reversible redox behavior due to the doping/dedoping process of the polymers, which was accompanied by a reversible electrochromic behavior. Electrochromic investigations showed that all three polymer films showed similar multichromic behaviors: green in the neutral state, gray in the oxidized state, and brick-red in the reduced state. Their band gap (Eg) values were elucidated utilizing spectroelectrochemical data and it was found to be around 1.18 eV. Furthermore, one of the polymer film was utilized for the construction of transmissive type electrochromic device (ECD) with poly(3,4-ethylenedioxythiophene) (PEDOT). (C) 2015 Elsevier Ltd. All rights reserved.Article Cu-y ve La-y Zeolit Katalizörleri Üzerinde 2-metilnaftalinin Metilasyon Kinetiği(2015) Niftaliyeva, Aysel; Güleç, Fatih; Şimşek, Emir H.; Karaduman, Ali; Güllü, Mustafa2,6-Dimetilnaftalin (2,6-DMN), yeni bir polimer olan polietilen naftalatın (PEN) monomerlerindenbiri 2,6-naftalin dikarboksilik asitin (2,6-NDCA) üretiminde kullanılan önemli bir dimetilnaftalindir.Dimetil naftalinlerin dokuz adet izomeri vardır ve bunların içinde, 2,6-DMN en önemlisidir. Günümüzekadar 2,6-DMN sentezi için değişik özelliklere sahip zeolit katalizörler kullanılmıştır. Bu çalışmada, Cuve La metalleri ile modifiye edilmiş Y zeolit (CBV720, yüzey alanı=726m2 /g\\ SiO2 /Al2 O 3 =30)katalizörler üzerinde 2 metil naftalinin (2- MN) metilasyonuyla 2,6- DMN sentezinde, deneysel olarakmetilasyon reaksiyonu hız ifadesinin bulunması amaçlanmıştır. Metilasyon reaksiyonunda reaktöre moloranı 1:5:5 olan 2 - MN: 1,3,5- trimetilbenzen (mezitilen): metanol karışımı beslenmiştir. Kinetikdeneylerinde, 2- MN dönüşümünün, 2,6- DMN oluşumunun, 2,6- DMN/2,7- DMN oranının, farklısıcaklık, boşluk hızı ve katalizör ile değişimleri bulunmuştur. Metilasyon kinetiğinde, 2- MN ve metanolderişimine bağlı reaksiyon hız ifadesi bulunmuştur. Arrhenius denklemi yardımıyla frekans faktörü (k0 )ve aktivasyon enerjisi (EA ) de hesaplanmıştır.Article Citation - WoS: 9Citation - Scopus: 10Lyapunov Type Inequalities for Nth Order Forced Differential Equations With Mixed Nonlinearities(Amer inst Mathematical Sciences-aims, 2016) Agarwal, Ravi P.; Ozbekler, AbdullahIn the case of oscillatory potentials, we present Lyapunov type inequalities for nth order forced differential equations of the form x((n))(t) + Sigma(m)(j=1) qj (t)vertical bar x(t)vertical bar(alpha j-1)x(t)= f(t) satisfying the boundary conditions x(a(i)) = x(1)(a(i)) = x(11)(ai) = center dot center dot center dot = x((ki))(ai) = 0; i = 1, 2,..., r, where a(1) < a(2) < ... < a(r), 0 <= k(i) and Sigma(r)(j=1) k(j) + r = n: r >= 2. No sign restriction is imposed on the forcing term and the nonlinearities satisfy 0 < alpha(l) < ... < alpha a(j) < 1 < alpha a(j+1) < ... < alpha(m) < 2. The obtained inequalities generalize and compliment the existing results in the literature.
