18 resultados para Evaluation methods for image segmentation
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Image segmentation is one of the image processing problems that deserves special attention from the scientific community. This work studies unsupervised methods to clustering and pattern recognition applicable to medical image segmentation. Natural Computing based methods have shown very attractive in such tasks and are studied here as a way to verify it's applicability in medical image segmentation. This work treats to implement the following methods: GKA (Genetic K-means Algorithm), GFCMA (Genetic FCM Algorithm), PSOKA (PSO and K-means based Clustering Algorithm) and PSOFCM (PSO and FCM based Clustering Algorithm). Besides, as a way to evaluate the results given by the algorithms, clustering validity indexes are used as quantitative measure. Visual and qualitative evaluations are realized also, mainly using data given by the BrainWeb brain simulator as ground truth
Resumo:
On the aggravation of social problems and the shortage of resources, the improvement of evaluation methods and control of its application, requiring more efficiency, efficacy, effectiveness and participation in its management, has been growing. As a result, emerges the importance of studying and developing such methodologies. The overall goal of this dissertation is to know what are the difficults to incorporate the point of view of executers and beneficiaries in evaluation process. To do so, has been done a research characterized as qualitative, with a field strategy using the case study of two social projects called Petrobras Child Program, situated in the metropolitan region of Natal, and Content Analysis technique for analyze the data. The conclusions of this work can assist in improving the process of projects evaluation financed by Petrobras, contributing with its social role, besides the possibility of encouraging a greater participation of other society actors, such as beneficiaries, in the evaluation process
Resumo:
Nowadays, evaluation methods to measure thermal performance of buildings have been developed in order to improve thermal comfort in buildings and reduce the use of energy with active cooling and heating systems. However, in developed countries, the criteria used in rating systems to asses the thermal and energy performance of buildings have demonstrated some limitations when applied to naturally ventilated building in tropical climates. The present research has as its main objective to propose a method to evaluate the thermal performance of low-rise residential buildings in warm humid climates, through computational simulation. The method was developed in order to conceive a suitable rating system for the athermal performance assessment of such buildings using as criteria the indoor air temperature and a thermal comfort adaptive model. The research made use of the software VisualDOE 4.1 in two simulations runs of a base case modeled for two basic types of occupancies: living room and bedroom. In the first simulation run, sensitive analyses were made to identify the variables with the higher impact over the cases´ thermal performance. Besides that, the results also allowed the formulation of design recommendations to warm humid climates toward an improvement on the thermal performance of residential building in similar situations. The results of the second simulation run was used to identify the named Thermal Performance Spectrum (TPS) of both occupancies types, which reflect the variations on the thermal performance considering the local climate, building typology, chosen construction material and studied occupancies. This analysis generates an index named IDTR Thermal Performance Resultant Index, which was configured as a thermal performance rating system. It correlates the thermal performance with the number of hours that the indoor air temperature was on each of the six thermal comfort bands pre-defined that received weights to measure the discomfort intensity. The use of this rating system showed to be appropriated when used in one of the simulated cases, presenting advantages in relation to other evaluation methods and becoming a tool for the understanding of building thermal behavior
Resumo:
The approach that undertakes this work revolves around the emergence of iconic structures on reflecting about the meaning of different methods of image representation through which the contemporaneity reveals itself. At baseline, three aspects are considered looking for an analytical ontology of the act of representation and imagery: the transition of representation in the oral culture of societies for writing, from these to typography, and finally the creation of a representation device. Resorted to, therefore, the argument by some genealogy reference points that technological instances such as writing, printing and photography, the evolution of this process, correspond, in itself, a consequent shift technique, for each representation precedent. In the area of the image, the most salient aspect of this change in foward process is the emergence of hyper-reality: the instances of hyper-realistic representation. In the Western context, the 'simulation of the world' - essential idea of mimesis is the work of an autonomous an conventional system. It should be noted, then the fact that under unreflective of the post-industrial societies, the mass-media image is coating with natural or fake code including - according to Baudrillard - tends to replace the real world in the "perpetuation of a large chain of simulacra." Hence in modern times, in the postindustrial society, during the crisis of the representation regimen and perception, centered in the referent. In this limit, new settings are established by aesthetic representations of imagery in contemporary culture: establishing spaces of simulation [Jean Baudrillard] the spectacle [Guy Debord] and hypermodernity [Gilles Lipovetsky] in which they operate. In these assemblages, saps the emergence of Hyper-reality Representation Instances - as seen in this study aesthetic events to configure itineraries of a new sensibility. It is the nature of this practice sign-iconic, ingrained in the creation of current artistic expression, which this research engaged in peering: the hyper-realistic setting, taking empirical support central to contemporary imagery production, diverse formats of analog representation.
Resumo:
According to great concern between the developed industrial activities and resultant impacts over the environment, an association of several factors have occurred, procedures to the efficient management of the rotation between economical development and the environment have been improved. A research in field have been realized inside building sites of companies in order to provide knowledge about the implemented and accomplish actions according to the resolution from CONAMA nº307. Trough the interview among the representations of the companies and photographic survey in loco, such as, what makes the companies implement this management, reutilization and recycling, transport and disposition. The present study had as objective: analyze the insertion of the used tools to residuals management, proposing improvements, in a way that it can be easily identified during the procedures execution in the building sites of the building companies of the city of Natal/RN. To reach the goal, in the first place a revision of the pertinent literature was performed; there for, it can be seen the relation between residues management and environment sustainability, once it happens in a continued way it may prevent the waste and reduces the risk that the activities way bring to the employees, community and environment; once found the great difficult faced with regard to labors, material, equipment, project, planning, costumer s interference, furnisher. And still, it could be verified wich materials generate greater indexes of residues in the works and the main occurrences of waste and loss. However a greater transparency is needed coming from the high administration in the commitment with the continued actions, to make it so, there must be a cultural change inside the company. There for there will be a greater productivity and quality of the under taking such as costumer s satisfaction
Resumo:
The natural resources degradation and its consequences to the society life have provided several discussions about the evaluation methods and environmental management, and the available means to minimize the effects of man s actions over the environment. Amongst these actions is the encouragement to the community participation in the process of carrying out the environmental programs, considering government and enterprises representatives or residents of certain places as social actors. Within these context, this paper had as a goal the investigation of the public participation in the environmental programs in areas that are susceptible to desertification, specificly in Parelhas/RN. The choice for this town was due to its insertion in an area considered as a desetification nucleous, which is, a region that suffers land degradation as a consequence of climate variations or human activities. Therefore, the research in question, of a descriptive and exploratory type, had as an instrument a structured questionnaire, applied to a sample of 223 people out of an 11,068 over 20 years of age residents population. The data have been tabled from Statistics for Windows Program and later interpreted based on the theoretical reference over the subject. As a result, corroborating to the literature of the area, it was found that the community participation in any type of action or debate about environmental questions is associated to the perception and knowledge about the problems. Although the people who were interviewed believe in the responsibility of the ceramic industry in causing environmental problems, they also believe that the benefits brought by the sector overcome such problems
Resumo:
In this work, we propose a multi agent system for digital image steganalysis, based on the poliginic bees model. Such approach aims to solve the problem of automatic steganalysis for digital media, with a case study on digital images. The system architecture was designed not only to detect if a file is suspicious of covering a hidden message, as well to extract the hidden message or information regarding it. Several experiments were performed whose results confirm a substantial enhancement (from 67% to 82% success rate) by using the multi-agent approach, fact not observed in traditional systems. An ongoing application using the technique is the detection of anomalies in digital data produced by sensors that capture brain emissions in little animals. The detection of such anomalies can be used to prove theories and evidences of imagery completion during sleep provided by the brain in visual cortex areas
Resumo:
A 3D binary image is considered well-composed if, and only if, the union of the faces shared by the foreground and background voxels of the image is a surface in R3. Wellcomposed images have some desirable topological properties, which allow us to simplify and optimize algorithms that are widely used in computer graphics, computer vision and image processing. These advantages have fostered the development of algorithms to repair bi-dimensional (2D) and three-dimensional (3D) images that are not well-composed. These algorithms are known as repairing algorithms. In this dissertation, we propose two repairing algorithms, one randomized and one deterministic. Both algorithms are capable of making topological repairs in 3D binary images, producing well-composed images similar to the original images. The key idea behind both algorithms is to iteratively change the assigned color of some points in the input image from 0 (background)to 1 (foreground) until the image becomes well-composed. The points whose colors are changed by the algorithms are chosen according to their values in the fuzzy connectivity map resulting from the image segmentation process. The use of the fuzzy connectivity map ensures that a subset of points chosen by the algorithm at any given iteration is the one with the least affinity with the background among all possible choices
Resumo:
The segmentation of an image aims to subdivide it into constituent regions or objects that have some relevant semantic content. This subdivision can also be applied to videos. However, in these cases, the objects appear in various frames that compose the videos. The task of segmenting an image becomes more complex when they are composed of objects that are defined by textural features, where the color information alone is not a good descriptor of the image. Fuzzy Segmentation is a region-growing segmentation algorithm that uses affinity functions in order to assign to each element in an image a grade of membership for each object (between 0 and 1). This work presents a modification of the Fuzzy Segmentation algorithm, for the purpose of improving the temporal and spatial complexity. The algorithm was adapted to segmenting color videos, treating them as 3D volume. In order to perform segmentation in videos, conventional color model or a hybrid model obtained by a method for choosing the best channels were used. The Fuzzy Segmentation algorithm was also applied to texture segmentation by using adaptive affinity functions defined for each object texture. Two types of affinity functions were used, one defined using the normal (or Gaussian) probability distribution and the other using the Skew Divergence. This latter, a Kullback-Leibler Divergence variation, is a measure of the difference between two probability distributions. Finally, the algorithm was tested in somes videos and also in texture mosaic images composed by images of the Brodatz album
Resumo:
Image segmentation is the process of subdiving an image into constituent regions or objects that have similar features. In video segmentation, more than subdividing the frames in object that have similar features, there is a consistency requirement among segmentations of successive frames of the video. Fuzzy segmentation is a region growing technique that assigns to each element in an image (which may have been corrupted by noise and/or shading) a grade of membership between 0 and 1 to an object. In this work we present an application that uses a fuzzy segmentation algorithm to identify and select particles in micrographs and an extension of the algorithm to perform video segmentation. Here, we treat a video shot is treated as a three-dimensional volume with different z slices being occupied by different frames of the video shot. The volume is interactively segmented based on selected seed elements, that will determine the affinity functions based on their motion and color properties. The color information can be extracted from a specific color space or from three channels of a set of color models that are selected based on the correlation of the information from all channels. The motion information is provided into the form of dense optical flows maps. Finally, segmentation of real and synthetic videos and their application in a non-photorealistic rendering (NPR) toll are presented
Resumo:
Image segmentation is the process of labeling pixels on di erent objects, an important step in many image processing systems. This work proposes a clustering method for the segmentation of color digital images with textural features. This is done by reducing the dimensionality of histograms of color images and using the Skew Divergence to calculate the fuzzy a nity functions. This approach is appropriate for segmenting images that have colorful textural features such as geological, dermoscopic and other natural images, as images containing mountains, grass or forests. Furthermore, experimental results of colored texture clustering using images of aquifers' sedimentary porous rocks are presented and analyzed in terms of precision to verify its e ectiveness.
Resumo:
Digital image segmentation is the process of assigning distinct labels to different objects in a digital image, and the fuzzy segmentation algorithm has been used successfully in the segmentation of images from several modalities. However, the traditional fuzzy segmentation algorithm fails to segment objects that are characterized by textures whose patterns cannot be successfully described by simple statistics computed over a very restricted area. In this paper we present an extension of the fuzzy segmentation algorithm that achieves the segmentation of textures by employing adaptive affinity functions as long as we extend the algorithm to tridimensional images. The adaptive affinity functions change the size of the area where they compute the texture descriptors, according to the characteristics of the texture being processed, while three dimensional images can be described as a finite set of two-dimensional images. The algorithm then segments the volume image with an appropriate calculation area for each texture, making it possible to produce good estimates of actual volumes of the target structures of the segmentation process. We will perform experiments with synthetic and real data in applications such as segmentation of medical imaging obtained from magnetic rosonance
Resumo:
This Thesis main objective is to implement a supporting architecture to Autonomic Hardware systems, capable of manage the hardware running in reconfigurable devices. The proposed architecture implements manipulation, generation and communication functionalities, using the Context Oriented Active Repository approach. The solution consists in a Hardware-Software based architecture called "Autonomic Hardware Manager (AHM)" that contains an Active Repository of Hardware Components. Using the repository the architecture will be able to manage the connected systems at run time allowing the implementation of autonomic features such as self-management, self-optimization, self-description and self-configuration. The proposed architecture also contains a meta-model that allows the representation of the Operating Context for hardware systems. This meta-model will be used as basis to the context sensing modules, that are needed in the Active Repository architecture. In order to demonstrate the proposed architecture functionalities, experiments were proposed and implemented in order to proof the Thesis hypothesis and achieved objectives. Three experiments were planned and implemented: the Hardware Reconfigurable Filter, that consists of an application that implements Digital Filters using reconfigurable hardware; the Autonomic Image Segmentation Filter, that shows the project and implementation of an image processing autonomic application; finally, the Autonomic Autopilot application that consist of an auto pilot to unmanned aerial vehicles. In this work, the applications architectures were organized in modules, according their functionalities. Some modules were implemented using HDL and synthesized in hardware. Other modules were implemented kept in software. After that, applications were integrated to the AHM to allow their adaptation to different Operating Context, making them autonomic.
Resumo:
This study aimed to construct and carry out a distance course of pedagogical training for health professional performing preceptorship functions in public health institutions. The preceptorship in health is a pedagogical practice that occurs in workplace, led by assistance professionals with teaching position or not, where the vast majority of these acts intuitively, reproducing their own training, confusing transmitting information with education. These preceptors often do not dominate the pedagogical knowledge, necessary for the organization of training activities, such as the various teaching-learning processes and the different assessment types. Student supervision is essential in the training process of students in the health field, and on the occasion of supervised internships that the teaching-learning process is based on practical experience with participation in real life situations and professional work. It was realized an exploratory study, descriptive with qualitative approach, with the development of tutoring teaching course in health as final product. Applied semi structured research instrument from may to july 2014. It were evaluated 162 health professionals who perform the preceptorship, which made it possible define the preceptor's profile and identify the educational requirements related to the educational process, which justified the construction of the program content and the professionals’ perception analysis about preceptorship through identification of three categories: clinic knowledge valuation; valuation of professional orientation and valuation of professional future. The course was available on distance mode through Moodle platform with forty hours of work load from October to November 2014. With the aim of capacitate the health professionals to development of necessary abilities and skills to tutoring performance through thoughts about tutoring concepts, professional training within the curricular guidelines and SUS precepts, the role of health professionals as educators, application of active teaching methodologies, and evaluation methods. The applications were done online through the provided link; 300 vacancies offered, 243 professionals applied, chosen 134 that works on tutoring, where 49 represented professionals that works on the location of the study. The course lasted 45 days, and counted with tutors responsible to interact and evaluate the students. 28 professionals joined the course, 12 concluded. Opportunities were identified to stimulate the involvement, however the professionals’ satisfaction shows that, make an investment on tutors education, starting from the Permanent Education precepts, will provide a bigger appropriation of the knowledge to the education and therefore the awareness of their role as an educator on work ambit, proportioning essential tools to tutors act while enabler of integration between theory and practice and result better teaching-learning process.
Resumo:
Breast cancer is the second type of cancer that affects more women of reproductive age in Brazil. Surgical treatments include: conserving surgery or mastectomy. Aimed to evaluate body image of women undergoing breast cancer surgery, based on the scale Body Image After Breast Cancer Questionnaire. It is a descriptive, exploratory, transversal, with a quantitative approach. Data were collected in Norte-riograndense League Against Cancer, between the months from March to May 2015, after consideration of the Research Ethics Committee of that institution CAEE 35155714.1.0000.5293. The study population consisted of women undergoing breast onco-surgery. To calculate the sample considered the finite population, totaling 120 subjects, collected four guys the most. Data were analyzed by the software Statistical Package for Social Sciences version 20.0. The domain scores of the scale were evaluated using descriptive and inferential statistics. The surgical group mastectomy without reconstruction showed greater impairment of body image in the field "vulnerability", "Care for the body" and "transparency" in relation to other surgical types, and suggests susceptibility to cancer, body appearance and worry that disturb other. The Kruskal-Wallis test showed greater dissatisfaction with body image in the fields "body Stigma" and "transparency" to the radical neoplastic surgery over other surgical types. Dissatisfaction with body image and physical appearance was detected in this study in all six image fields present in scale, with emphasis on the "body Stigma" and "Transparency". This means that the body image disorder is formulated based on the perception of others about themselves and not by perception "self", which justifies the concern with appearance, with body and hide the consequences stemmed cancer. It is expected that the data obtained from the evaluation of body image presented in this study contribute to enable the assistance to oncocirurgiada woman breast integral, essential for the practice of Nursing.