A multiscale constitutive model for intergranular stress corrosion cracking in type 304 austenitic stainless steel

Peer reviewedPublisher PD

Synthesis Of Derivatives Of 3-(4-cyanophenyl)thieno[3,2-b]thiophene And Their Electronic And Optoelectronic Applications

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2016Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2016İlk elektrolüminesans (EL) olayı 1936 yılında Destriau ve arkadaşlarınin elektrik akımıni inorganik maddeye uygulamasiyla olusan thermal olmayan ışık olarak gözlenmiştir. Izolatöre dağılmış iki elektrot arasında paketlenmiş olan ZnS fosfor tozundan yüksek alan elektrolüminesans elde ettiler. General Electric şirketi inorganik yarı iletken GaAsP’e dayalı ışık yayan cihazı ticaretleştiren ilk firmadır. İlk LED’ler yarı iletken malzemelerin enerji band aralıklarına göre sadece kırmızı ışık yayabilmektedirler. Yeni malzemelerin gelişimi turuncu, sarı ve yeşil gibi diğer renkleri, hemde kızılötesi erişilebilir maddeleri saglamistir. Yüksek çözünürlük ve ekran kare hizini sağlayan daha karmaşık ve daha yüksek performanslı devre için gelecek talep, hala gelişmiş yük taşıyıcı mobilitesine sahip organik yarı iletkenler gerektirmektedir. OLED’lerin performansını optimize etmek için, aktif bileşenler olarak incelenen birçok konjuge organik maddeler bulunmaktadır. Küçük organik yarı iletken moleküller, moleküller arası etkili yük transferini kolaylaştıran düzlemsel konformasyonda π-konjuge aromatik halkalar ile birlikte istifleme göstermektedir. Onların eşsiz özelliklere sahip olmalari nedeniyle, alan-etkili transistör, güneş hücreleri, ışık yayan diyotlar, elektrokromik, fotokromık cihazları, sensörler, lazer gibi uygulamalarda aktif maddeler olarak kullanılmaktadırlar. Ayrıca, düşük molekül ağırlıkları nedeniyle vakum biriktirme yoluyla ince filmler olarak elektrolüminesans cihazların yapımı için çok uygun maddelerdir. Buna rağmen, katı halde çok ciddi bir porblem olan “aggregation-caused quenching” (istiflenme ile sonümlenme, ACQ) olarak adlandırılan bir olay yaşanmaktadır. Bu nedenle, OLED performansını en uygun hale getirmek için bu etkiyi en aza indirmek gerekmektedir. Bu çalışmanın amacı, optoelektronik uygulamaları araştırmak için düzenli π-elektron alıcı ve verici gruplardan oluşan düşük band aralığına sahip konjuge organik molekülleri sentezlemektir. Birlesik tiyofen halkası, mesela, tiyenotiyofen, elektron açısından zengin olmasindan dolayı elektron verici grup olarak davranmaktadır. Buna ek olarak, elektronca zengin yapılarından dolayı elektron donör gruplar olarak trifenilamin (TPA) ve tetrafeniletilenin (TPE) yanı sıra, tiyenotiyofen yapısınin C-3 konumunda substitue olan elektron çekici nitril grubunu iceren para-CN-C6H5 bulunmaktadır. Ayrıca, tetrafeniletilen “aggregation-caused quenching” (ACQ)’in aksine “aggregation induced emission (istiflenmeyle ışıma, AIE)” olayını için incelenmekte ve OLED malzemeler geliştirmek için kullanılmaktadir. Başka bir deyişle, tiyenotiyefon iceren π-elektron alıcı ve TPA veya TPE elektron verici donor-akseptor organik moleküller olarak davrandıklarından elektronik ve optoelektronik uygulamaları için uygun malzemelerin sentezinde öncülük edeceklerdir. Bu bağlamda, TT’nin C-3 konumunda para CNPh tasiyan, CNPhTT, maddenin sentezi grubumuz tarafından geliştirilen PPA monoketon halka kapama yoluyla yapılmıştır. Daha sonra, TPA ve TPE boronat kompleksleri sırasıyla sentezlendi. Daha sonra, sonuç organik maddeler metal katalizatorlü Suzuki çapraz keletlenme reaksiyonu ile sentezlenmiştir. Bu bağlamda, tieno [3,2-b] tiofen, nitril grubu (CNPhTT) çekirdek birimi ile ikame olan fenil kısmı C-3 ‘(PhTT), grubumuz tarafından geliştirilen PPA monoketan halka kapama yoluyla sentezlendi. Daha sonra, TPA ve DYP karşılık gelen boronat kompleksi sırasıyla sentezlendi. Daha sonra, nihai organik maddeler, metal katalizli Suzuki çapraz birleştirme reaksiyonları ile sentezlenmiştir.In 1936, the phenomenon of electroluminescence (EL), that is a non-thermal generation of light coming up from application of electric current on a inorganic substrate, was first observed by Destriau et al. They observed high field electroluminescence from a ZnS phosphor powder dispersed in an isolator and sandwiched between two electrodes. General Electric was the first company that commerciallized light-emitting device which it was based on the inorganic semiconductor GaAsP. Early LED’s were able to emit only red light as energy gap of those semiconducting materials were in that region of light. The evolution of further materials allowed access to other colours such as orange, yellow and green, as well as infrared accessible compounds. Future demand for more complex and higher performing circuitry, enabling high-resolution, video-rate displays still requires organic semiconductors with enhanced charge carrier mobility. There are many organic conjugated materials that are investigated as an active components in order to optimize the performance of OLED’s. Among them small organic semiconducting molecules are exhibited to pack closely together with their π-conjugated aromatic rings linked in a planar conformation, allowing efficient intermolecular charge transfer. Owing to the fact that they have unique properties, they are used as active materials in applications, like field-effect transistors, solar cells, light emitting diodes, electrochromic windows, photochromic devices, sensors, lasers. Moreover, they are very convenient in terms of building up electroluminescent devices due to their low molecular weight, allowing them to be vaccum deposited as thin films. However, they are suffering from a phenomenon that is called “aggregation-caused quenching” (ACQ), that becomes a very serious problem in solid state. Hence, it is required to minimize this effect in order to optimize OLED’s performance. A large number of oligomers and polymers are synthesized by using different metal-catalyzed cross-coupling reactions like Suzuki, Stille, Sonogashira, and Kumada-type reactions. These methods have been used to synthesize organic semiconductor materials possesing critical properties such as having appropriate electronic band gap, high charge carrier mobility, low cost starting materials and convenient manufacture of thin films. High fluorescence emitting efficieny in solid state is fundamental aspect for organic light emitting diodes but in the field-effect transistors, low electronic band gap and high charge mobility are crucial. The purpose of this work is synthesizing low band gap conjugated organic molecules which consist of regular π-electron acceptor and donor groups in order to investigate their optoelectronic applications. Owing to the fact that fused thiophene ring like thienothiophene is electron rich group, therefore it can be served as an electron donor group. In addition, it has phenyl moiety (PhTT) at C-3, substitued by withdrawing group, nitrile, on the contrary triphenylamine (TPA) and tetraphenylethylene (TPE) act as an electron donor groups because of their electron rich structures. Additionally, tetraphenylethylene has been investigated for aggregation induced emission (AIE) phenomenon that is oppsite of aggregation-caused quenching (ACQ) effect and used to develop OLED materials. In another words, thienothiopehene based π-electron acceptor and π-electron donor TPA or TPE, act as donor-acceptor organic molecules leads to synthesis of suitable materials for electronic and optoelectronic applications. In this respect, thieno[3,2-b]thiophene, having—phenyl moiety (PhTT) at C-3, substitued with nitrile group (CNPhTT) core unit was synthesized by monoketone ring closure route with PPA that was developed by our group. Afterwards, corresponding boronate complex of TPA and TPE were synthesized respectively. Then, final organic materials were synthesized by metal-catalyzed Suzuki cross-coupling reactions.Yüksek LisansM.Sc

Estudar o efeito mental da cor na arquitetura interior dos espaços hospitalares e afetar a tranquilidade do paciente

Interior architecture plays a major role in the building environment quality. Setting quality and space partitioning, color and material of the surface coverage, lighting, furniture, and etc. are the factors affecting the beauty of the interior spaces. Effect of environment psychology such as color and light on the human senses and its feedback in the environment influences the environment quality. Colors around us, not only possess the ability to transfer the message and emotion, but also possess the energy therapy property. Color psychology means the effect of environment on the mind and mental states of people through the stunning available in the environment. This fact is of great importance in the therapeutic Spaces because a patient that goes to the hospital , is in the unfavorable conditions and therefore it should be tried to reduce the patient anxiety and increase the hope of life and restore the patient’s tranquility. Thus, people strictly need the variety of color and form and combined artworks in the around environment. Generally, using the diverse colors and suitable lighting eliminates the uniformity in the environment and impatience in the patients and avoids weakening of the senses and the nervous system. Therefore , by knowing the topic of environment psychology and use the color and light in the therapeutic space and by the descriptive method, in this study we try to investigate the effect of colors on the different diseases and classify them quantitatively in order to create a sense of relaxation and more satisfaction in patients. Recent studies have reported that accurate use of the special colors can create useful effect in the mind balance and health, physical and mental relaxation, and in result rapid restore of health in the recovery time.La arquitectura interior juega un papel importante en la calidad del entorno de la construcción. Establecer la calidad y el espacio de particionamiento, el color y el material de la cobertura de la superficie, la iluminación, los muebles, etc. son los factores que afectan la belleza de los espacios interiores. El efecto de la psicología ambiental, como el color y la luz en los sentidos humanos y su retroalimentación en el ambiente, influye en la calidad del ambiente. Los colores que nos rodean no solo poseen la capacidad de transferir el mensaje y la emoción, sino que también poseen la propiedad de terapia energética. La psicología del color significa el efecto del medio ambiente en la mente y los estados mentales de las personas a través del aturdimiento disponible en el entorno. Este hecho es de gran importancia en los Espacios terapéuticos porque un paciente que acude al hospital, se encuentra en las condiciones desfavorables y por lo tanto se debe tratar de reducir la ansiedad del paciente e incrementar la esperanza de vida y restablecer la tranquilidad del paciente. Por lo tanto, las personas necesitan estrictamente la variedad de colores y formas y obras de arte combinadas en el entorno circundante. En general, el uso de colores diversos y una iluminación adecuada elimina la uniformidad en el entorno y la impaciencia en los pacientes y evita el debilitamiento de los sentidos y el sistema nervioso. Por lo tanto, al conocer el tema de la psicología ambiental y utilizar el color y la luz en el espacio terapéutico y el método descriptivo, en este estudio tratamos de investigar el efecto de los colores sobre las diferentes enfermedades y clasificarlos cuantitativamente para crear un sentido de relajación y más satisfacción en los pacientes. Estudios recientes han informado que el uso preciso de los colores especiales puede crear un efecto útil en el equilibrio mental y la salud, la relajación física y mental y, en consecuencia, la restauración rápida de la salud en el tiempo de recuperación.A arquitetura de interiores desempenha um papel importante na qualidade do ambiente de construção. Estabeleça a qualidade e o espaço de partição, a cor e o material da cobertura da superfície, a iluminação, o mobiliário, etc. são os fatores que afetam a beleza dos espaços interiores. O efeito da psicologia ambiental, como cor e luz nos sentidos humanos e seu feedback no ambiente, influencia a qualidade do ambiente. As cores que nos cercam não só têm a capacidade de transferir a mensagem e a emoção, mas também possuem a propriedade da terapia energética. A psicologia da cor significa o efeito do ambiente na mente e nos estados mentais das pessoas através do deslumbramento disponível no ambiente. Esse fato é de grande importância nos Espaços Terapêuticos, pois um paciente que chega ao hospital, está em condições desfavoráveis e, portanto, deve tentar diminuir a ansiedade do paciente e aumentar a expectativa de vida e restaurar a tranquilidade do paciente. Portanto, as pessoas precisam estritamente da variedade de cores e formas e obras de arte combinadas no ambiente circundante. Em geral, o uso de diversas cores e iluminação adequada elimina a uniformidade do ambiente e a impaciência nos pacientes e previne o enfraquecimento dos sentidos e do sistema nervoso. Portanto, conhecer o tema da psicologia ambiental e cor uso e luz no espaço terapêutico e o método descritivo, neste estudo nós investigamos o efeito de cores em diferentes doenças e classificar quantitativamente para criar uma sensação de relaxamento e mais satisfação nos pacientes. Estudos recentes relatam que o uso preciso de cores especiais pode criar um efeito útil no equilíbrio mental e na saúde, relaxamento físico e mental e, conseqüentemente, a rápida restauração da saúde no tempo de recuperação

Studying the Emotional Intelligence and Emotion Regulation Skills in Adults with Attention-Deficit/Hyperactivity Disorder (ADHD)

Introduction: Several Studies have shown that the clinical symptoms of Attention Deficit/Hyperactivity Disorder (ADHD) include an emotional dysregulation and deficits in emotional intelligence. Present study aimed to study emotional intelligence and emotion regulation skills in adults with ADHD. Methods: Participants were 40 newly diagnosed adults with ADHD (65% female, 35% male, mean age 27.5 years, ranged from 19 to 43 years old). Symptoms were assessed using Conner’s Adult ADHD Rating Scales. The control group included 40 subjects who were selected using convenient sampling method. Both groups completed the 36-item Difficulties in Emotion Regulation Scale (DERS) and the 90-item Persian version of Bar-On Emotional Quotient Inventory (EQ-i). Data were analyzed using MANOVA. Results: Findings showed that clinical group differed significantly from control subjects with respect to their overall emotion regulation skills and emotional intelligence scores (p<0.01). Conclusions: Adults with Attention-Deficit/Hyperactivity Disorder had more difficulties in emotion regulation and more deficits in emotional intelligence compared to normal subjects. Declaration of Interest: None

Learning with Limited Data and Supervision

Deep neural networks have been the main driving force of recent successes in machine learning leading to the deployment of these models in a wide range of industries such as healthcare, autonomous driving, and fintech. Despite the great success, these models are known as data-hungry models requiring many labelled training examples and costly computational resources to solve a pre-determined task. Several obstacles limit the applicability of deep learning models in real-world scenarios. First, annotating large-scale training data in tasks such as object localization or segmentation is cumbersome and demands huge time and labor. Second, in real-world scenarios and applications such as field robotics, the models may be required to learn new classes in an ever-changing environment. However, accessing abundant fully labelled training data for novel classes may be infeasible. Therefore, a model needs to adapt to learn novel classes given only a few examples with simple (weak) annotations. Finally, it is known that most modern deep convolutional networks do not have calibrated confidence scores, meaning that the confidence scores they assign to the outcomes do not match the true frequency of those events. These models are of utmost importance to output calibrated prediction scores that the downstream applications can rely upon, especially in safety-critical applications. This thesis focuses on tackling these limitations in deep learning models with applications in Computer Vision. We investigate the task of finding common objects in small image collections and propose an efficient graphical model inference algorithm that utilizes the structure of the problem to reduce the computational time compared to traditional inference algorithms significantly. We also propose a probabilistic approach to solve the few-shot common object localization problem based on a parametric distribution of each class on a unit sphere. We further extend our model to localize objects of novel classes in unseen images. In the next step, we study pairwise similarity knowledge transfer for weakly supervised object localization to reduce the cost of labor and time in annotating large-scale object detection datasets for novel classes. We learn the similarity functions and the assignment of proposals to different novel classes jointly using alternating optimization and show that the assignment problem becomes an integer linear program for a certain type of loss function. Furthermore, we propose an efficient inference algorithm to overcome the difficulty of computing all pairwise similarities. Finally, to overcome pre-trained models' accuracy degradation in learning expressive probability calibration functions using small calibration data, we introduce and formalize the notion of order-preserving functions. We also present two sub-families of order-preserving functions that benefit from parameter sharing across different classes in classification problems