Medical Image Denoising Using Mixed Transforms

يقترح في هذا البحث طريقة تعتمد على خليط من التحويلات Wavelet Transform(WT) و Multiwavelet Transform (MWT) من اجل تقليل التشوه في الصور الطبية . تعتمد الطريقة المقترحة على استخدام WT  و MWT بالتعاقب لتعزيز اداء ازالة التشوه من الصور الطبية. عمليا , يتم في البداية اضافة تشويه لصور الرنين المغناطيسي (MRI) والتصوير المقطعي المحوسب (CT)  من اجل الاختبار. ثم تعالج الصورة المشوهة بواسطة WT  لتنتج اربع تقسيمات للصورة موزعة على اساس التردد ويعالج كل تقسيم بواسطة MWT  قبل مرحلة ازالة التشوه المكثفة او البسيطة. اوضحت النتائج العملية ان نسبة الاشارة الى الضوضاء (PSNR) تحسنت بشكل ملحوظ وتم المحافظة على المعلومات الاساسية للصورة. بالاضافة الى ذلك, فان متوسط نسبة الخطا انخفض تبعا لذلك بالمقارنة مع الطرق الاخرى. In this paper,  a mixed transform method is proposed based on a combination of wavelet transform (WT) and multiwavelet transform (MWT) in order to denoise medical images. The proposed method consists of WT and MWT in cascade form to enhance the denoising performance of image processing. Practically, the first step is to add a noise to Magnetic Resonance Image (MRI) or Computed Tomography (CT) images for the sake of testing. The noisy image is processed by WT to achieve four sub-bands and each sub-band is treated individually using MWT before the soft/hard denoising stage. Simulation results show that a high peak signal to noise ratio (PSNR) is improved significantly and the characteristic features are well preserved by employing mixed transform of WT and MWT due to their capability of separating noise signals from image signals. Moreover, the corresponding mean square error (MSE) is decreased accordingly compared to other available methods

A unifying theory of tests of rank

The general principles underlying tests of matrix rank are investigated. It is demonstrated that statistics for such tests can be seen as implicit functions of null space estimators. In turn, the asymptotic behaviour of the null space estimators is shown to determine the asymptotic behaviour of the statistics through a plug-in principle. The theory simplifies the asymptotics under a variety of alternatives of empirical relevance as well as misspecification, clarifies the relationships between the various existing tests, makes use of important results in the numerical analysis literature, and motivates numerous new tests. A brief Monte Carlo study illustrates the results

Metal Assisted Nanowire Growth for Silicon Nanowire/Amorphous Silicon Composite Solar Cell

Solar cells are photovoltaic devices that convert the energy of light to electricity by the photovoltaic effect. Crystalline silicon-based solar cells are the most dominant solar cells in the market today due to the high efficiency and relatively low cost. However, the cost of such solar cell is still high due to the large amount of material that is consumed in fabricating such a device. Polycrystalline/amorphous thin films and nanomaterial technologies have emerged to reduce the high cost of c-Si based solar cells and increase the efficiency. In this research, we combined these two technologies to propose and fabricate silicon nanowires (SiNWs)/amorphous Silicon (a-Si) composite solar cell structure at low temperatures using heavily doped polycrystalline silicon/glass as a substrate. Silicon Nanowire (SiNW) is one of the promising 1D semiconductor nanomaterial which has recently attracted significant attention due to its potential applications in many fields, including photovoltaic (PV) solar cells. SiNW is a term that is used widely to describe a rod with a diameter of between 1 to 100 nm and length of several microns. The vertical array geometry of such a device has great advantages in increasing the efficiency of solar cells due to its high light absorption and efficient light scattering. Replacing the silicon with polycrystalline silicon that was fabricated on glass substrate by means of aluminum induced crystallization method of amorphous silicon is considered a significant step in reducing the cost since glass is a cheaper material. In this research, heavily doped polycrystalline (p+ polySi/ITO/glass) silicon film was fabricated successfully by the means of aluminum induced crystallization of a-Si on ITO/glass substrate. Raman spectroscope, optical microscope, Hall Effect measurement, and SEM were used for the characterizing the (p+ polySi/ITO/glass). P-type SiNW were grown successfully in the PECVD system on silicon, a-Si/ITO/glass, and p+ polySi/ITO/glass substrates using Au nanoparticles as a catalyst at temperatures between (310 ˚C and 346 ˚C). It is to be noted that this temperature range is still lower than the eutectic temperature of Au-Si (363 ˚C). SEM and TEM systems were used to characterize the SiNW on c-Si and p+ polySi/ITO/glass substrates

Testing subspace Granger causality

The methodology of multivariate Granger non-causality testing at various horizons is extended to allow for inference on its directionality. Empirical manifestations of these subspaces are presented and useful interpretations for them are provided. Simple vector autoregressive models are used to estimate these subspaces and to find their dimensions. The methodology is illustrated by an application to empirical monetary policy, where a conditional form of Okun’s law is demonstrated as well as a statistical monetary policy reaction function to oil price changes

Geometric and long run aspects of Granger causality

This paper extends multivariate Granger causality to take into account the subspaces along which Granger causality occurs as well as long run Granger causality. The properties of these new notions of Granger causality, along with the requisite restrictions, are derived and extensively studied for a wide variety of time series processes including linear invertible processes and VARMA. Using the proposed extensions, the paper demonstrates that: (i) mean reversion in is an instance of long run Granger non-causality, (ii) cointegration is a special case of long run Granger non-causality along a subspace, (iii) controllability is a special case of Granger causality, and finally (iv) linear rational expectations entail (possibly testable) Granger causality restriction along subspaces

Habilidades de redação desenvolvidas por meio do conteúdo integrado à linguagem

The aim of the study is to find out writing skills for business purposes that can be developed through Language Integrated Content. This was a exprimenal study and data was collected by questionnaires. To conduct this research, 20 teachers were selected as statistical sample. the results showed that there is significant difference in the performance of the students in the experimental group in which the CLIL was used. Students in the control group were taught features of business writing in the traditional way. Some sample business letters were also shown to them. Language teachers had a definitely positive attitude towards CLIL. They were prepared to create content with deliberate integration of desired language items or ready to identify content from various subjects that are packed with language items.El objetivo del estudio es descubrir las habilidades de escritura para fines comerciales que se pueden desarrollar a través del contenido integrado de Language. Este fue un estudio exprimenal y los datos fueron recolectados por cuestionarios. Para llevar a cabo esta investigación, 20 profesores fueron seleccionados como muestra estadística. los resultados mostraron que existe una diferencia significativa en el rendimiento de los estudiantes en el grupo experimental en el que se utilizó el CLIL. A los estudiantes del grupo de control se les enseñaron las características de la escritura empresarial de la manera tradicional. También se les mostraron algunas muestras de cartas comerciales. Los profesores de idiomas tenían una actitud definitivamente positiva hacia CLIL. Estaban preparados para crear contenido con la integración deliberada de los elementos del idioma deseado o listos para identificar el contenido de varias materias que están llenas de elementos del idioma.O objetivo do estudo é descobrir habilidades de escrita para fins comerciais que possam ser desenvolvidas através do Conteúdo Integrado da Linguagem. Este foi um estudo experimental e os dados foram coletados por questionários. Para conduzir esta pesquisa, 20 professores foram selecionados como amostra estatística. os resultados mostraram que há diferença significativa no desempenho dos alunos do grupo experimental em que o CLIL foi utilizado. Os alunos do grupo de controle foram ensinados recursos de escrita de negócios da maneira tradicional. Alguns exemplos de cartas comerciais também foram mostrados a eles. Os professores de línguas tinham uma atitude positiva em relação ao CLIL. Eles estavam preparados para criar conteúdo com integração deliberada de itens de linguagem desejados ou prontos para identificar conteúdo de vários assuntos que estão repletos de itens de linguagem

The Spectral Approach to Linear Rational Expectations Models

This paper considers linear rational expectations models in the frequency domain under general conditions. The paper develops necessary and sufficient conditions for existence and uniqueness of particular and generic systems and characterizes the space of all solutions as an affine space in the frequency domain. It is demonstrated that solutions are not generally continuous with respect to the parameters of the models, invalidating mainstream frequentist and Bayesian methods. The ill-posedness of the problem motivates regularized solutions with theoretically guaranteed uniqueness, continuity, and even differentiability properties. Regularization is illustrated in an analysis of the limiting Gaussian likelihood functions of two analytically tractable models.Comment: JEL Classification: C10, C32, C62, E3

The Ethics of Decoration in Architecture

اقترن التزيين ومنذ القدم بمختلف الانجازات الانسانية وعدته بعض الطروحات كماليا لا الزاميا قابل للازالة والطرح يمكن الاستغناء عنه، واسيء فهمه كونه مجرد اضافة ووسيلة للتجميل لخصائصه الفنية لاسيما صيغة الحلي الديكورية ، وعلى عكس مفهوم الاخلاق الالزامي المقترن بالاغراض النفعية والقيمية على السواء، ليبرز ذلك التعارض بين المفهومين ضرورة مناقشتهما معا للكشف والتقصي عن الجوانب الاخلاقية للتزيين في النتاج المعماري تحديدا لتقويض تلك الافكار التي عدت التزيين فائضا لا غير،فتوضحت مشكلة البحث بـ "عدم وجود تصور واضح حول المؤشرات الاخلاقية للتزيين في نتاج العمارة "، وبالتالي تحدد هدف البحث بـ "طرح المؤشرات الاخلاقية للتزيين في النتاج المعماري في مستوى المخططات والواجهات"، ووضع البحث فرضيته البحثية متمثلة بـ "تبرز اخلاقيات التزيين في العمارة ضمن المستويين الباطن والظاهر على السواء، في كل من المخططات والواجهات وصولا لتحقيق هيأة الناتج المعماري ككل" ، ولاختبار صحتها اعتمد البحث منهجا استقرائيا ركز على كشف مؤشرات الوظيفة الاخلاقية للتزيين في النتاج المعماري وصولا الى طرح اطار نظري خاص لمؤشرات التزيين الاخلاقية في النتاج المعماري على مستوى المخططات والواجهات معا ،اذ تم التأكد من وقوع التزيين في مستوى المخطط والواجهة على السواء وبما أكد التزامه بالجوانب النفعية الوظيفية البيئية الانشائية الاقتصادية وبما يحقق السلامة والامان ، فضلا عن التزامه بالجوانب الجمالية التعبيرية والرمزية الاتصالية لاسيما التكتونية اذ حددت هيأة النتاج المعماري ككل ووصلت ذروتها اليوم بعد تطورها الى التكتونية الرقمية لانتاج السطوح الرقمية والتي وصفت كجلود لتداخل بنية (الهيكل- القشرة) ومادتهما معا نسجتها عملية التزيين بفضل الامكانات الرقمية لتمثيل السطح الرقمي فضاءا او نسيجا ميتافيزيقيا ومجالا حيا انتقاليا لمختلف القيم الوظيفية والجمالية في العصر الحالي بما اغنى وظيفية المخططات وتعبيرية الواجهات على السواء.The decoration has been associated with various human achievements since ancient times and has been considered by some of theses  as an additional, non-mandatory , can be probability  remove , subtract and dispensable. It is misunderstood as a mere addition and an instrument  for beauty as its artistic characteristics, especially the decorative  jewelry. In contrast to the concept of mandatory  ethics concept  which associated with both for purposes and values aspects, that contrast highlighted the need to discuss them together to investigate the ethical aspects of decorating in architectural output to undermine those ideas, which considered decorating as a surplus only. The research problem was explained by "absence  a clear conception of the ethical indicators of decorating the product of architecture", Thus the goal of the research is that "put the ethical indicators of decoration the architectural output at the level of plans and facades" , so the research put hypothesis as "highlighting the ethics of decoration within both the subcontractor and the apparent levels In each of plans and facades, to achieve architectural output as a whole", it focused on uncovering the ethical indicators of decoration the architectural output, in order to present a special theoretical framework for the indicators of moral decoration at the level of plans and the facades together, It has been confirmed that the decoration at the level of the plans and the facade both, that confirmed its commitment to the functional aspects economic , safety environmental construction, as well as to the aesthetic aspects of expressive and symbolic especially Tectonics, as determined the apperance of architectural output as a whole Today, after its development into digital tectonics for the production of digital surfaces, which were described as skins to overlap the structure (the structure - the skin) and their material together weaving decoration process thanks to the digital potentials to represent the digital surface space or metaphysical fabric and a living space for various functional and aesthetic values in the current era, including richer functional plans and expression facades