Mitigation of H.264 and H.265 Video Compression for Reliable PRNU Estimation

The photo-response non-uniformity (PRNU) is a distinctive image sensor characteristic, and an imaging device inadvertently introduces its sensor's PRNU into all media it captures. Therefore, the PRNU can be regarded as a camera fingerprint and used for source attribution. The imaging pipeline in a camera, however, involves various processing steps that are detrimental to PRNU estimation. In the context of photographic images, these challenges are successfully addressed and the method for estimating a sensor's PRNU pattern is well established. However, various additional challenges related to generation of videos remain largely untackled. With this perspective, this work introduces methods to mitigate disruptive effects of widely deployed H.264 and H.265 video compression standards on PRNU estimation. Our approach involves an intervention in the decoding process to eliminate a filtering procedure applied at the decoder to reduce blockiness. It also utilizes decoding parameters to develop a weighting scheme and adjust the contribution of video frames at the macroblock level to PRNU estimation process. Results obtained on videos captured by 28 cameras show that our approach increases the PRNU matching metric up to more than five times over the conventional estimation method tailored for photos

Flexible ceramic polymer composite substrates with spatially variable dielectrics for miniaturized RF applications

The goal of this research is to develop a process suitable for producing monolithic conformal substrates with a spatial arrangement of material cells according to a particular design creating novel material systems, useful for many multi- functional electronic and Radio Frequency devices. In this study, MCT ceramics (Mg-Ca-Ti-O systems) and organic binders (polymer solution) are mixed and fabricated as films through a process called tape casting to compromise between high dielectric constant and flexibility. Prior to optimizing the process, several characterization studies are carried out: Commercial spray dried MCT powders (Transtech Inc.) with dielectric constant k=70 and k=20 were analyzed as pressed and produced into tape cast films. Dielectric properties are then measured by an Agilent 16451B material analysis kit and their microscopic behavior is examined by scanning electron microscopy. Results show that flexible composite films show a maximum dielectric constant of e~22 unlike their powder pressed form with e ~16 but their loss behavior deteriorates when compared with their sintered form and a loss tangent factor of 0.001. The difference is attributed to the air content vs. polymer presence of the material in powder pressed form. Also, these substrates naturally are no longer flexible; hence studies are focused on their tape cast form. The potential of these dielectric shades to serve as candidate constituents for producing monolithic textured polymer-ceramic-composites with controllable loss is studied further. Four properties are of prime importance: tunability of dielectric constants to achieve miniaturization, flexibility via low temperature processing of polymers and loss controllability

Electromagnetic Imaging Of Dielectric Rough Interfaces

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2008Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2008Bu çalışmada, engebeli dielektrik arayüzlerin elektromanyetik görüntülenmesi üzerinde çalışılmıştır. Konu iki bölümde ele alınmıştır: İlk olarak mükemmel iletken düzlem üzerindeki dielektrik yüzeyin elde edilmesi problemi incelenmiştir, ikinci olarak ise üzerinde dielektrik katmanlar bulunan dielektrik yüzeyin elde edilmesi problemi aynı metot ile incelenmiştir. Tek boyutta değişimlerin olduğu yüzeylerin sabit frekanslı düzlemsel dalgalar tarafından aydınlatıldığı durum göz önüne alınmıştır. Hesaplanacak yüzeyin üzerinde kalan bölgede ve yüzeye paralel bir çizgi üzerindeki saçılan alan ölçümleri problemin çözümünde kullanılacaktır. Saçılan alan Fourier Dönüşümü ve Taylor Açılımı ile ifade edilir; problemin çözümü sınır koşulları kullanılarak elde edilen lineer olmayan denklem sisteminin çözümüne indirgenir. Denklem sisteminin çözümünde ise Newton Metodu yinelemeli bir şekilde uygulanırken regularizasyon uygulanmasını gerektirir. Bu çalışmada Tikhonov Regularizasyonu uygulanmıştır. Ayrıca, daha doğru sonuçlar elde edilmesi için kimi durumlarda En Küçük Kareler Yöntemi kullanılmıştır. Benzetim sonuçları, problemde kullanılan parametrelerin etkisine bağlı olarak incelenmiştir. Sonuç olarak iki problem için de dalgaboyu/200 genlikli hasarların bile tespit edilebildiği gösterilmiştir ve kullanılan metodun; ters saçılım problemlerinde önemli bir konu olan ve çok geniş kapsamlı pratik uygulamalara sahip tahribatsız muayene için etkili olduğu gösterilmiştir.In this study, electromagnetic imaging of dielectric rough interfaces is presented with simulation results. The subject is presented in two cases: First, dielectric rough surface located over a perfectly conducting plane is reconstructed and second, dielectric surface beyond a layered media is reconstructed using the same method. Considering surfaces having variation only in one space dimension, plane electromagnetic wave with a fixed frequency is used for excitation. Scattered field measurements on a paralel line above the surface to be reconstructed are used and a special representation of the scattered field in terms of Fourier Transform and Taylor expansion is used in boundary conditions which leads to the solution of a system of nonlinear equations where Newton Method is applied iteratively with some kind of regularization. In this study, Tikhonov regularization is applied. In addition, in some cases, least square regularization is applied in order to get more accurate results. The simulation results are discussed with the effects of parameters used in the problems. Finally it can be shown that, satisfactory results are obtained in reconstructing the defects on the surfaces with the amplitude of wavelength/200 in both problems and the method can be effectively used in non-destructive testing of materials which is an important subject in the inverse scattering theory with its wide range of practical applications.Yüksek LisansM.Sc

Electrochemistry and determination of cefdinir by voltammetric and computational approaches

AbstractThe oxidation and reduction behavior of cefdinir (CEF) was studied by experimental methods and computational calculations at B3LYP/6-31+G (d)//AM1. Voltammetric studies were carried out based on two irreversible reduction peaks at approximately −0.5 and −1.2 V on a hanging mercury drop electrode (HMDE) and on one irreversible oxidation peak at approximately 1.0 V on a glassy carbon electrode (GCE) versus Ag/AgCl, KCl (3.0M) in Britton–Robinson (BR) buffer at pH 4.2 and 5.0, respectively. Differential pulse adsorptive stripping voltammetric methods have been developed and validated for determination of CEF in different samples. The linear range was established as 0.25–40.0 μM for HMDE and 0.40–10.0 μM for GCE. Limit of quantification was calculated to be 0.20 and 0.26 μM for HMDE and GCE, respectively. These methods were successfully applied to assay the drug in tablets and human serum with good recoveries between 92.7% and 107.3% having relative standard deviation less than 10%

Iatrogenic Port Site Parasitic Myoma; Case Report and Literature Review

Introduction: We report a case of iatrogenic parasitic myoma of the anterior abdominal wall and discuss the differential diagnosis, treatment, and prevention of complication with relevant literature. Case Report: A 33-year-old woman presented with anterior abdominal wall mass 3 years after initial laparoscopic myomectomy surgery. A mass with a 38 3 26 mm diameter was observed in the anterior abdominal wall at the site of inferior left side port of previous surgery. It was excised from the anterior abdominal wall outside of the peritoneum, below the fascia. The pathologic examination of the excised mass revealed cellular myoma. This case is the 4th port site parasitic myoma in literature. Conclusion: The risk of implantation and subsequent growth of minute myoma fragments should be kept in mind during morcellation procedures and, in order to avoid such complications, all fragments should be tracked during morcellation. The inspection of trocar sites after the removal of trocars for retained fragments would prevent such recurrences

An Investigation into the Cultural Dimension in EFL Classes: Turkish Instructors’ Views and Practices

The current study aims to investigate how Turkish English as a foreign language (EFL) teachers understand the cultural component in language classes and the extent to which they feel to have opportunities to raise cultural awareness. The views on and approaches to cultural issues of ten English language instructors teaching at the tertiary level across state and private universities in Turkey have been examined in this regard. A qualitative-quantitative mixed-method design using a questionnaire and semi-structured individual interviews has been adopted. The findings revealed that the teachers' opportunities to raise their students' cultural awareness were not satisfactory, and there was a mismatch between their wishes and practices. They felt ill-prepared to include culture and tackle cultural controversies in class. Their conceptualization of culture in English language classes was predominantly modern from a received view of culture yet included elements from which interculturality may develop.La présente étude vise à étudier comment les enseignants turcs d'Anglais langue étrangère (ALE) comprennent la composante culturelle des cours de langue et dans quelle mesure ils se sentent capables de sensibiliser à la culture. Dans cette perspective, les points de vue et les approches des questions culturelles de dix professeurs d'anglais enseignant au niveau supérieur dans les universités publiques et privées de Turquie ont été examinés. Une conception de méthodologie mixte qualitative-quantitative à travers un questionnaire et un entretien individuel semi-structuré a été adoptée. Les résultats ont révélé que les possibilités offertes aux enseignants de sensibiliser leurs élèves à la culture n'étaient pas satisfaisantes et qu'il y avait un décalage entre leurs souhaits et leurs pratiques. Ils se sentaient mal préparés à inclure la culture et à s'attaquer aux controverses culturelles en classe. Leur conceptualisation de la culture dans les cours de langue anglaise était principalement moderne à partir d'une vision reçue de la culture, mais comprenait des éléments à partir desquels l'interculturalité pouvait se développer

Can vitamin D, B12, folic acid, inflammatory markers and H. pylori effective in the process of chronic spontaneous urticaria?

Background: Etiopathogenesis in Chronic Spontaneous Urticaria (CSU) is not completely clear. Some vitamins, inflammatory markers and even some microorganisms have been held responsible for this process. There are limited number of publications in this field in the literature. The aim of this study is to shed light on the etiology of chronic urticaria.Methods: This study included a total of 90 patients that 45 with CSU patients and 45 healthy subjects who admitted to Allergy and Clinical Immunology and Internal Medicine outpatient clinics of University of Health Sciences, Bursa Postgraduate Research and Training Hospital between October 2018 and June 2019. They were between the ages of 18-55. Both groups were examined for CRP, Procalcitonin (PCT), Erythrocyte Sedimentation Rate (ESR), Vitamin B12, vitamin D, folic acid and Helicobacter pylori (H. pylori) antibody.Results: ESR, CRP, PCT, Vitamin B12 and Vitamin D levels were not statistically different according to the groups (p>0.05). Folic acid levels were significantly different between groups (p=0.026; p<0.05); the low folic acid ratio in the healthy group is higher than in the urticaria group. There was no statistically significant difference between the groups according to H. pylori antibody positivity (p>0.05). In urticaria group, sufficient vitamin D ratio was higher in who were H. pylori antibody negative. In healthy group; insufficient and sufficient vitamin D ratio was higher in who were H. pylori antibody positive.Conclusions: There is no direct correlation between urticaria and Vitamin B12, Vitamin D, folic acid deficiencies and inflammatory biomarkers. CRP, ESR and PCT levels may be generally normal as in patients with urticaria. However, CRP may also increase slightly in patients with severe urticaria. It may be wrong to see H. pylori as a direct cause of urticaria

An EFL Instructor’s Study and Teach Abroad Experiences and Complementary Views from Learners

The present qualitative case study aimed to explore the influences of an EFL instructor’s study and teach abroad experiences on her classroom implementations. It additionally investigated her students’ responses to the reflections of her study and teach abroad in the classroom. The findings revealed that these experiences contributed to the instructor’s both personal development and professional learning and further had impacts on her teaching practices. An in-depth analysis of multiple data tools; a semi-structured, individual interview with the instructor, her journal entries, and an open-ended questionnaire from 43 language learners, informed that study and teach abroad experiences contributed to the instructor’s world knowledge and intellectual growth through her teaching and other academic endeavors at an abroad university. It was also found that the learners appreciated the instructor’s explicitly referring to her international contacts as a means of providing authentic input, enriching the lesson content, fostering engagement in the class, and raising learners’ intercultural awareness. This study suggests developing teacher interculturality via study and teach abroad programs should be encouraged to better address intercultural topics in the language class. The process of preparing intercultural language teachers could be aided by teacher study and/or teach abroad programs

Pre-Service Teachers' Attitudes towards STEM: Differences Based on Multiple Variables and the Relationship with Academic Achievement

STEM education has benefits for students, such as increasing achievement and improving attitudes, motivation, interest toward STEM disciplines, and higher-order thinking skills. Teachers' characteristics, perceptions, and attitudes related to STEM influence teachers' implementation of integrative STEM approaches and, as a result, shape the learning environment. This study examined 513 pre-service teachers' attitudes towards STEM in terms of multiple variables (department, class level, gender, having a traineeship, or information about STEM) and investigates the relationship between participants' attitudes and academic grade point averages. Participants were pre-service preschool, classroom, science, and mathematics teachers that can be considered the basis of the STEM pipeline. Data were collected via a survey and were analyzed using descriptive statistics, t-test, ANOVA, and Pearson product-moment correlation. Results show that pre-service science teachers, senior pre-service teachers, and participants who had information or a traineeship about STEM had more positive attitudes towards STEM. There was no relationship between attitudes and grade points. It was also seen that the attitudes towards engineering-technology explain the most variance in the attitudes towards STEM. Therefore, the teacher preparation programs should give more attention to integrate the courses of science, technology, engineering, and mathematics and help the pre-service teachers (regardless of their departments) to realize the connectedness of STEM subjects

Facioscapulohumeral Muscular Dystrophy Without Facial Symptoms

DergiPark: 378994tmsjIntroduction: Facioscapulohumeral muscular dystrophy (FSHD) is a progressive muscular dystrophy which starts with shoulder and face muscles involvement and rarely spreads to pelvic muscles. It has autosomal dominant inheritance pattern, serum CK levels are normal or mildly high, and EMG is myopathic. Case report:We present the 43 year old male patient with pain, numbness and weakness in cervical area and both arms for 1 year. His mother has similar symptoms as well. His cervical spinal nerve EMG results were found normal. Results:EMG results were found normal. Our patient had the defect of closing eyelids or pressing them based on faced muscles involvement just like regular FSHD cases. Because of the atrophy of lower face muscles, lips seemed to be fuller. On the other hand, there was a no whistling or blowing defects related to orbicularis oris muscle and face involvement. We presented this study as this muscle disease represents itself with weakness and numbness in muscle is seen rarely in literature and our patient did not have one of its components (facial)