Automatic Nonlinear Filtering and Segmentation for Breast Ultrasound Images

Breast cancer is one of the leading causes of cancer death among women worldwide. The proposed approach comprises three steps as follows. Firstly, the image is preprocessed to remove speckle noise while preserving important features of the image. Three methods are investigated, i.e., Frost Filter, Detail Preserving Anisotropic Diffusion, and Probabilistic Patch-Based Filter. Secondly, Normalized Cut or Quick Shift is used to provide an initial segmentation map for breast lesions. Thirdly, a postprocessing step is proposed to select the correct region from a set of candidate regions. This approach is implemented on a dataset containing 20 B-mode ultrasound images, acquired from UDIAT Diagnostic Center of Sabadell, Spain. The overall system performance is determined against the ground truth images. The best system performance is achieved through the following combinations: Frost Filter with Quick Shift, Detail Preserving Anisotropic Diffusion with Normalized Cut and Probabilistic Patch-Based with Normalized Cut

Framework for progressive segmentation of chest radiograph for efficient diagnosis of inert regions

Segmentation is one of the most essential steps required to identify the inert object in the chest x-ray. A review with the existing segmentation techniques towards chest x-ray as well as other vital organs was performed. The main objective was to find whether existing system offers accuracy at the cost of recursive and complex operations. The proposed system contributes to introduce a framework that can offer a good balance between computational performance and segmentation performance. Given an input of chest x-ray, the system offers progressive search for similar image on the basis of similarity score with queried image. Region-based shape descriptor is applied for extracting the feature exclusively for identifying the lung region from the thoracic region followed by contour adjustment. The final segmentation outcome shows accurate identification followed by segmentation of apical and costophrenic region of lung. Comparative analysis proved that proposed system offers better segmentation performance in contrast to existing system

A Brief Review of Machine Learning Algorithms in Forest Fires Science

Due to the harm forest fires cause to the environment and the economy as they occur more frequently around the world, early fire prediction and detection are necessary. To anticipate and discover forest fires, several technologies and techniques were put forth. To forecast the likelihood of forest fires and evaluate the risk of forest fire-induced damage, artificial intelligence techniques are a crucial enabling technology. In current times, there has been a lot of interest in machine learning techniques. The machine learning methods that are used to identify and forecast forest fires are reviewed in this article. Selecting the best forecasting model is a constant gamble because each ML algorithm has advantages and disadvantages. Our main goal is to discover the research gaps and recent studies that use machine learning techniques to study forest fires. By choosing the best ML techniques based on particular forest characteristics, the current research results boost prediction power

Patch-based Denoising Algorithms for Single and Multi-view Images

In general, all single and multi-view digital images are captured using sensors, where they are often contaminated with noise, which is an undesired random signal. Such noise can also be produced during transmission or by lossy image compression. Reducing the noise and enhancing those images is among the fundamental digital image processing tasks. Improving the performance of image denoising methods, would greatly contribute to single or multi-view image processing techniques, e.g. segmentation, computing disparity maps, etc. Patch-based denoising methods have recently emerged as the state-of-the-art denoising approaches for various additive noise levels. This thesis proposes two patch-based denoising methods for single and multi-view images, respectively. A modification to the block matching 3D algorithm is proposed for single image denoising. An adaptive collaborative thresholding filter is proposed which consists of a classification map and a set of various thresholding levels and operators. These are exploited when the collaborative hard-thresholding step is applied. Moreover, the collaborative Wiener filtering is improved by assigning greater weight when dealing with similar patches. For the denoising of multi-view images, this thesis proposes algorithms that takes a pair of noisy images captured from two different directions at the same time (stereoscopic images). The structural, maximum difference or the singular value decomposition-based similarity metrics is utilized for identifying locations of similar search windows in the input images. The non-local means algorithm is adapted for filtering these noisy multi-view images. The performance of both methods have been evaluated both quantitatively and qualitatively through a number of experiments using the peak signal-to-noise ratio and the mean structural similarity measure. Experimental results show that the proposed algorithm for single image denoising outperforms the original block matching 3D algorithm at various noise levels. Moreover, the proposed algorithm for multi-view image denoising can effectively reduce noise and assist to estimate more accurate disparity maps at various noise levels

Deep Learning for Automated Detection of Cyst and Tumors of the Jaw in Panoramic Radiographs

Patients with odontogenic cysts and tumors may have to undergo serious surgery unless the lesion is properly detected at the early stage. The purpose of this study is to evaluate the diagnostic performance of the real-time object detecting deep convolutional neural network You Only Look Once (YOLO) v2-a deep learning algorithm that can both detect and classify an object at the same time-on panoramic radiographs. In this study, 1602 lesions on panoramic radiographs taken from 2010 to 2019 at Yonsei University Dental Hospital were selected as a database. Images were classified and labeled into four categories: dentigerous cysts, odontogenic keratocyst, ameloblastoma, and no cyst. Comparative analysis among three groups (YOLO, oral and maxillofacial surgeons, and general practitioners) was done in terms of precision, recall, accuracy, and F1 score. While YOLO ranked highest among the three groups (precision = 0.707, recall = 0.680), the performance differences between the machine and clinicians were statistically insignificant. The results of this study indicate the usefulness of auto-detecting convolutional networks in certain pathology detection and thus morbidity prevention in the field of oral and maxillofacial surgery.ope

Joaquim Rodrigo:a contínua reinvenção da pintura

Tese de doutoramento, História (História da Arte), Universidade de Lisboa, Faculdade de Letras, 2014A pintura de Joaquim Rodrigo surge, na sequência de dois anos de aprendizagem autodidata, em 1952, integrada na abstração geométrica, que então tinha escassos desenvolvimentos no contexto nacional. Trata-se de uma pintura informada pelas abstrações do Salon des Réalités Nouvelles com cores planas e saturadas, recortadas em formas geométricas não racionais e imbricadas umas nas outras. Participa, em 1954, no Iº Salão de Arte Abstrata e a partir dessa época denota um processo de racionalização das formas e do cromatismo que, num primeiro momento reduz aquelas aos elementos geométricos base e procura uma teoria da cor próxima de Herbin, para num segundo momento proceder a uma síntese que passa pela modularização do espaço da superfície pictórica e o recurso às cores primárias. Uma apropriação de Mondrian ocorre, para estabelecer um confronto racionalista com este no que respeita a divisão do espaço. A construção de uma teoria da cor própria, em 1959, permite atingir uma unidade autoexplicativa entre a matriz, a forma e a cor, característica da arte concreta. Em 1961, a sua pintura sofre uma alteração radical e as formas dão lugar a signos e estes organizam-se no plano de modo narrativo. A coexistência de estruturas abstratas, como a grelha, confere-lhes novas funções. Uma aproximação à pintura de outras culturas não ocidentais tem lugar de forma inédita, já que esta reporta a relação política entre colonizador e colonizado. As suas pinturas confrontam assim o interdito modernista da narrativa e afirmam-se como testemunhos dos conflitos políticos da vida portuguesa. A inscrição dos signos e destas narrativas no plano opaco da pintura rejeita a sua analogia com o campo visual natural para a definir como espaço votado à própria articulação dos signos. A partir de 1969, uma formalização estrutural da sua linguagem pictórica manifesta-se. A redução da paleta a quatro cores (vermelho, amarelo, branco e preto) permite que, misturadas com homogeneidade, definam o plano pictórico e individualmente combinadas tracem os signos isolados na superfície da pintura. Estes reportam-se a viagens. São formados a partir de perceções e do diferimento destas pela memória e da memória para a sua inscrição, destituindo qualquer simultaneidade entre perceção e conhecimento. As relações que traçam entre si não são explícitas porque cada signo constitui um acontecer fora de uma ordem de causas e efeitos. Uma proliferação de códigos e diferentes regimes semióticos atravessa estes signos. A relação com outras culturas ocorre agora como uma tradução cultural, que permite destituir as dominâncias dos processos de significação, no quadro da própria cultura ocidental. Na medida em que narrativa e viagem se equivalem estes signos constituem também uma prática do espaço. Como processo mnemónico produzido pela pintura consignam a esta um arquivo. Em 1972, Joaquim Rodrigo realiza uma retrospetiva da sua pintura na SNBA que foi bem recebida pela crítica e permitiu compreender a relevância maior do seu projeto. A teorização que Joaquim Rodrigo desenvolveu preocupou-se sobretudo com a necessidade de reinventar o medium da pintura sem refutar de modo reativo convenções modernistas, mas redefinindo-as e construindo uma nova estrutura recursiva para a pintura. As várias redefinições do seu sistema levaram-no à construção de uma linguagem pictórica com um rigor semelhante ao de uma língua, suscetível de ser utilizada por todos e atualizada em cada realização. As pinturas finais, que desenvolve a partir de 1984, as únicas dentro do último sistema que construiu designou-as de pinturas certas. Uma nova espacialidade se manifesta numa colagem e metamorfose de espaços-tempos organizada pela distribuição da cor por áreas quantitativas. A relação com a pintura grega arcaica e com o pensamento présocrático ocuparam esta fase final, como vestígios de um imemorial sempre procurado e desaparecido a cada realização. A última pintura é realizada em 1990 e um projeto para um painel de azulejos em 1995.After two years of self-taught, Joaquim Rodrigo’s painting come up to the forefront in 1952, engaged in the geometric abstraction trend that had just a few developments in the Portuguese context. He based his painting on the abstraction movements from the Salon des Réalités Nouvelles. The flat colours, cropped in nonrational geometrical forms overlapping each other characterize his first works. In 1954, he participates in the Ist Abstract Art Exhibition, and from that period on a process of rationalization of form and chromaticism took place. In a first moment, the forms were reduced to basic geometric elements he searched a colour theory nearby Herbin, then in a second moment he proceeded to a synthesis based on a modularization of pictorial surface with recourse to primary colours. The appropriation he does of Mondrian aims to provide a rationalist confrontation with this painter, regarding questions related to the division of space. In 1959, Joaquim Rodrigo constructs his own theory of colour that allows him to build a selfexplanatory unity formed by surface, form and colour, characteristic of concrete art. However his painting suffers a radical twist, in 1961. Forms give way to signs and these organize in a narrative over the pictorial plane. The coexistence of these new elements with abstract structures, as the grid, confers on them new functions. Also an approach to the painting of non-Western cultures manifests in a new way, once that it reports the political relation between colonizer and colonized. These new paintings also confront the modernist interdict of narrative and claim themselves as testimonies of the political conflicts of the Portuguese life. The inscription of signs and its narratives in the surface’s opacity of painting rejects any analogy with the naturalist visual field in order to define painting’s surface as a space intended for the articulation of signs. From 1969 on a structural formalization of his own pictorial language reveals itself as his main task. The reduction of the palette to four colours (red, yellow, white and black) enables their mixture to define the pictorial surface and each one individually combined permit to trace the signs. These ones isolated in the surface are related to journeys. They are constituted from perceptions and their deferral by memory and from memory to its inscription in a process that dismisses any possible simultaneity between perception and knowledge. The relations established among signs are not explicit as each one is an event out of any order of causes and effects. A proliferation of codes and different semiotic regimes goes through them. The relationship with other cultures these signs manifest know is also a cultural translation that deprives any kind of dominance in the signification process as it happens in the framework of the Western culture. In that narrative and journey are equivalent, these signs constitute a practice of space. As a mnemonic process produced by painting, they consign it in an archive. In 1972, Joaquim Rodrigo organizes a retrospective exhibition of his own work at SNBA, which was well received by the critique and provided the understanding of the major relevance of his project. Joaquim Rodrigo developed a theoretical thought mainly concerned with the need to reinvent the medium of painting without rebutting modernist conventions on a reactive basis, but resetting them and building a new recursive structure for painting. The several redefinitions of his system brought him to build a pictorial language with a similar rigor of an idiom (langue), susceptible of everybody’s use and actualized in each performance. The final paintings, he develops from 1984 on, the only few integrated in the last theoretical system he had built, were designated as the right paintings. A new spatiality is declared as a collage and a metamorphosis of several space-times organized by the distribution of colour through quantitative areas. The relationship with archaic Greek painting and with pre-Socratic thought occupied him in that final stage, as traces of an immemorial always searched and vanished at each achievement. His last painting was executed in 1990 and a project for a wall in 1995

A review of feature-based retinal image analysis

Retinal imaging is a fundamental tool in ophthalmic diagnostics. The potential use of retinal imaging within screening programs, with consequent need to analyze large numbers of images with high throughput, is pushing the digital image analysis field to find new solutions for the extraction of specific information from the retinal image. The aim of this review is to explore the latest progress in image processing techniques able to recognize specific retinal image features. and potential features of disease. In particular, this review aims to describe publically available retinal image databases, highlight different performance evaluators commonly used within the field, outline current approaches in feature-based retinal image analysis, and to map related trends. This review found two key areas to be addressed for the future development of automatic retinal image analysis: fundus image quality and the affect image processing may impose on relevant clinical information within the images. Performance evaluators of the algorithms reviewed are very promising, however absolute values are difficult to interpret when validating system suitability for use within clinical practice