317 research outputs found

    Scene understanding through semantic image segmentation in augmented reality

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    Abstract. Semantic image segmentation, the task of assigning a label to each pixel in an image, is a major challenge in the field of computer vision. Semantic image segmentation using fully convolutional neural networks (FCNNs) offers an online solution to the scene understanding while having a simple training procedure and fast inference speed if designed efficiently. The semantic information provided by the semantic segmentation is a detailed understanding of the current context and this scene understanding is vital for scene modification in augmented reality (AR), especially if one aims to perform destructive scene augmentation. Augmented reality systems, by nature, aim to have a real-time modification of the context through head-mounted see-through or video-see-through displays, thus require efficiency in each step. Although there are many solutions to the semantic image segmentation in the literature such as DeeplabV3+, Deeplab DPC, they fail to offer a low latency inference due to their complex architectures in aim to acquire the best accuracy. As a part of this thesis work, we provide an efficient architecture for semantic image segmentation using an FCNN model and achieve real-time performance on smartphones at 19.65 frames per second (fps) while maintaining a high mean intersection over union (mIOU) of 67.7% on Cityscapes validation set with our "Basic" variant and 15.41 fps and 70.3% mIOU on Cityscapes test set using our "DPC" variant. The implementation is open-sourced and compatible with Tensorflow Lite, thus able to run on embedded and mobile devices. Furthermore, the thesis work demonstrates an augmented reality implementation where semantic segmentation masks are tracked online in a 3D environment using Google ARCore. We show that the frequent calculation of semantic information is not necessary and by tracking the calculated semantic information in 3D space using inertial-visual odometry that is provided by the ARCore framework, we can achieve savings on battery and CPU usage while maintaining a high mIOU. We further demonstrate a possible use case of the system by inpainting the objects in 3D space that are found by the semantic image segmentation network. The implemented Android application performs real-time augmented reality at 30 fps while running the computationally efficient network that was proposed as a part of this thesis work in parallel

    Anlık Basınç Yükü Altındaki Basit Mesnetli Plakların Dinamik Davranışının Diferansiyel Kareleme Yöntemi İle İncelenmesi

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    Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2008Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2008Plak ve kabuk yapılar üstünde anlık basınç yükü etkisinin, söz konusu yapıların tasarımı sürecinde önemli bir yeri vardır. Anlık basınç yükünün yapılar üstündeki etkilerini gözlemlemek amacıyla yapılan deneyler zor ve maliyetlidir. Bu nedenle, bu tür yükler altındaki yapıların dinamik davranışını incelemek için sayısal çalışmalar yapılmaktadır. Bununla birlikte, problemin zamana bağlı olması çözüm zamanını artırmakta ve yeni sayısal yöntemlerin araştırılmasını gerektirmektedir. Diferansiyel kareleme yöntemi (Differential quadrature method) lineer ve lineer olmayan kısmi diferansiyel denklemlerin çözümü için önerilmiş sayısal bir çözüm tekniğidir. Yöntem bugüne kadar birçok mühendislik problemine başarıyla uygulanmış ve özellikle yapısal analiz konusunda geniş bir uygulama alanı bulmuştur. Yöntemin işlem yükünü azaltarak yüksek hassasiyette çözümler üretebilme yeteneği uygulanma alanlarını genişletmektedir. Bu makalede diferansiyel kareleme yöntemi ile anlık basınç yüküne maruz izotropik ve katmanlı kompozit dört kenarından basit mesnetli olarak tutturulmuş plakların dinamik davranışı incelenmiştir. Elde edilen sonuçlar yine bu çalışmada elde edilen teorik ve sonlu elemanlar sonuçları ile karşılaştırılmıştır.The effect of blast load on the plate and shell structures has an important role on design decision. Blast load experiments are usually difficult and expensive. Therefore, numerical studies have been done on the response of blast loaded structures. However, because of time dependency of the nature of the problem, numerical solutions take long time and need heavy computational effort. The differential quadrature method (DQM) is a numerical solution technique for the rapid solution of linear and non-linear partial differential equations. It has been successfully applied to many engineering problems. The method has especially found application widely in structural analysis such as static and free vibration analysis of beams and plates. The capability of the method to produce highly accurate solutions with minimal computational efforts makes it of current interest. In this paper, the dynamic behavior of simply supported isotropic and laminated composite plates under air blast load has been investigated using the differential quadrature method. The results are compared to the theoretical and finite element results obtained in this study

    Flow cytometric maturity score as a novel prognostic parameter in patients with acute myeloid leukemia

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    The European LeukemiaNet (ELN) classification is widely accepted for risk stratification of patients with acute myeloid leukemia (AML). In order to establish immunophenotypic features that predict prognosis, the expression of single AML blast cell antigens has been evaluated with partly conflicting results; however, the influence of immunophenotypic blast maturity is largely unknown. In our study, 300 AML patients diagnosed at our institution between January 2003 and April 2012 were analyzed. A flow cytometric maturity score was developed in order to distinguish "mature" AML (AML-ma) from "immature" AML (AML-im) by quantitative expression levels of early progenitor cell antigens (CD34, CD117, and TdT). AML-ma showed significantly longer relapse-free survival (RFS) and overall survival (OS) than AML-im (p < 0.001). Interestingly, statistically significant differences in RFS and OS were maintained within the "intermediate-risk" group according to ELN (RFS, 7.0 years (AML-ma) vs. 3.3 years (AML-im); p = 0.002; OS, 5.1 years (AML-ma) vs. 3.0 years (AML-im); p = 0.022). Our novel flow cytometric score easily determines AML blast maturity and can predict clinical outcome. It remains to be clarified whether these results simply reflect an accumulation of favorable molecular phenotypes in the AML-ma subgroup or whether they rely on biological differences such as a higher proportion of leukemia stem cells and/or a higher degree of genetic instability within the AML-im subgroup

    500 KW Rüzgar Türbini İçin Ana Şaft Tasarımı Ve Analizi

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    Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2013Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2013Bu çalışmada, 500 kW güç üreten bir rüzgar türbinin ana şaftının tasarımı ve yapısal analizleri yapılmıştır. Ana şaftın boyutlandırılmasında yorulma kriterlerinin esas alınması gerekmektedir. Ana şaftın yorulmaya ait yük durumu ise literatürde bulunan ampirik formüller kullanılarak hesaplanmıştır. Yorulma analizlerinde şaftı çevrimsel yüklerle zorlayan rotor ağırlığının yanında rüzgar kesmesi ve kule blokaj etkisi vb. sebeplerle ortaya çıkan değişken eğilme momenti ve tork değerleri de hesaba katılmıştır. Ana şaftın kritik kesitlerindeki çap hesabı, ASME Eliptik yorulma kriteri kullanılarak sonsuz ömre göre yapılmıştır. Ana şaftın tasarımındaki kritik bölgeler şaftın yataklandığı bölge ve şaftın dişli kutusuna bağlandığı bölgedir. Ayrıca, kontrol amaçlı olarak Uluslararası Elektroteknik Komisyonu’nun (International Electrotechnical Commision) yayınlamış olduğu IEC 64100-1 standardında belirtilen yükleme şartları için ana şaftın statik analizleri ANSYS 14.5 sonlu elemanlar yazılımı kullanılarak gerçekleştirilmiştir. Şaftın sonlu eleman modeli SOLID185 elemanlar kullanılarak oluşturulmuştur. Ayrıca, ana şaft - göbek bağlantı elemanlarının analizi de bu çalışma kapsamında yapılmıştır. Sayısal ve analitik yöntemler kullanılarak elde edilen deformasyon ve gerilme sonuçları karşılaştırılmış ve iyi bir uyum olduğu görülmüştür.In this paper, the main shaft which is one of the important structural parts for a 500 kW wind turbine has been designed. The fatigue criteria has been based on sizing the main shaft. The main shafts critic desing loads have been calculated by empirical formulas which are on the literatures. Oscillation moments of the torque and the flexural moments which is created by wind share, and effect of tower, etc. have been envisaged for analytical and numerical studies. In this study, the main shaft has been designed for infinite life using with ASME Elliptic criteria. There are two critic areas which are supported and connected to the gear box. In addition Iternational Electrotechnical Commision (IEC) 64100-1 standards have been based on the critic design load cases. The main shaft and the fasteners are modeled using the finite element method. The finite element model of the shaft is designed using with SOLID185 elements. Its static analysis have been achieved with using ANSYS 14.5 software. Also a comparison of two different approximations have been mentioned in this paper. The values of analitic and numerical of deplacement and stress are compared each

    Otobüslerde Kullanılan Plastik Yakıt Tanklarının Statik Ve Dinamik Analizler Yardımıyla Dayanımının İncelenmesi

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    Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2015Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2015Günümüzde, otobüslerde kullanılmakta olan konvansiyonel metal yakıt tankları yerini plastik yakıt tanklarına bırakmaktadır. Bu makalede, plastik yakıt tanklarının, statik ve dinamik analizlere dayalı, bilgisayar destekli, geliştime-tasarım projesinn bir kısmı sunulmuştur. Öncelikle, plastik malzemenin mekanik özelliklerini bulmaya yönelik kupon testleri gerçekleştirilmiştir. Statik analizlerde yakıt tankına eşdeğer yükler uygulanmıştır. Dinamik analizler ise zamanla değişen yük, yakıt ve tankın atalaet momentleri göz önüne alınmış ve modal transient analiz yöntemi kullanılmıştır. Statik analizlerde, eşdeğer statik yükleme yaklaşımı kullanılmaktadır. Yapılan dinamk analizlerde, akışkan akustik elemanlar kullanılarak modellenmiştir. Yakıt tankı farklı doluluk oranları için incelenerek karşılaştırılmış ve sonuçları bu bildiride paylaşılmıştır.Nowadays, the conventional metal fuel tanks used in buses are being replaced with plastic fuel tanks. In this paper, a part of the project which aims to develop a computer aided methodology for developing/designing of the plastic fuel tanks based on static and dynamic analysis is presented. Coupon tests are first conducted to acquire the mechanical properties of the plastic material. In the static analysis, equivalent static loads are applied to the fuel tanks. In the dynamic analysis, the time varying loading and the inertia of the fluid and fuel tanks are taken into account using modal transient analysis. Fluid which is in the tank is modeled with acoustic approach in dynamic analysis. In this paper, different fullness ratios of the fuel tank are investigated and both results are compared each other

    Influencia de un injerto en el perfil de ácidos grasos y algunas propiedades fisicoquímicas de la semilla y el aceite de semillas de sandía

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    This study aimed to investigate the effects of grafting on the fatty acid profile and some physicochemical properties of watermelon seed and seed oil. The ‘Crimson Tide’ cultivar was used as the scion while two wild watermelon (Citrullus lanatus&nbsp;var.&nbsp;citroides&nbsp;(A1 and A2)), one&nbsp;Lagenaria siceraria&nbsp;(A3) and one&nbsp;Cucurbita maxima&nbsp;Duchesne x&nbsp;Cucurbita moschata&nbsp;Duchesne (A4) were used as rootstocks. The use of rootstock significantly influenced the fatty acid profile and the physical parameters of seeds and seed oils. The highest linoleic acid ratio was found in the seed oil from A1 and A2, the oil from A3 had the highest oleic acid ratio. The results showed that the content and acid value in seed oils were improved, and that total phenolic compounds and antioxidant activity of both seed and oil were decreased by grafting. Wild rootstocks can be used in watermelon cultivation to obtain a watermelon seed which is rich in linoleic acid.El objetivo de este estudio fue investigar los efectos del injerto en el perfil de ácidos grasos y algunas propiedades fisicoquímicas de la semilla y el aceite de semillas de sandía. El cultivar ‘Crimson Tide’ se utilizó como vástago, mientras que dos sandías silvestres (Citrullus lanatus&nbsp;var.&nbsp;Citroides&nbsp;(A1 y A2)), una&nbsp;Lagenaria siceraria&nbsp;(A3) y una&nbsp;Cucurbita maxima&nbsp;Duchesne x&nbsp;Cucurbita moschata&nbsp;Duchesne (A4) se utilizaron como portainjertos. El uso de portainjertos influyó significativamente en el perfil de ácidos grasos y los parámetros físicos de semillas y aceites de semillas. La proporción de ácido linoleico más alta se encontró en el aceite de semillas de A1 y A2, el aceite de A3 tuvo la proporción de ácido oleico más alta. Los resultados mostraron que el contenido de aceite y el índice de acidez mejoró y los compuestos fenólicos totales y la actividad antioxidante tanto de la semilla como del aceite se redujeron mediante el injerto. Para obtener un aceite de semillas de sandía rico en ácido linoleico, se pueden utilizar portainjertos silvestres en el cultivo de sandía

    Optical and XPS evidence for the electrochemical generation of an N-heterocyclic carbene and its CS2 adduct from the ionic liquid [bmim][PF6]

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    Room temperature ionic liquids continue to be at the forefront of chemistry, covering a broad spectrum of research areas from electrochemistry and energy to catalysis and green chemistry. Therefore, it is of great value to fully understand the chemical and electrochemical reactivity and stability of ionic liquids utilized in these applications. In this context, we have investigated the electrochemical generation of an N-heterocyclic carbene and its CS2 adduct from the ionic liquid [bmim][PF6], and X-ray photoelectron spectroscopy (XPS) proved to be a highly effective spectroscopic tool to study such systems. Initially, the dithiocarboxylate adduct was chemically synthesized as a reference compound starting from both [bmim][PF6] and [bmim][OAc], and characterized by HRMS, and 1H- and 13C-NMR, FTIR, visible and X-ray photoelectron spectroscopy. While a simple mixture of [bmim][PF6] and CS2 revealed no evidence of adduct formation, the application of an electrochemical stimulus led to the formation of the dithiocarboxylate adduct as evidenced optically and through the newly formed S2p peak in the XP spectrum. Further evidence for the electrochemical reduction of [bmim][PF6] to the corresponding N-heterocyclic carbene came from the XPS analysis via the appearance of a new N1s peak in the XP spectrum. © 2017 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique
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