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#### Brain hematoma computational segmentation

(IOP Publishing, 2018)

In computed tomography imaging, brain hematoma (BH) segmentation is a very
challenging process due to a high variability of BH morphology, low contrast and noisy
images. Because of this, BH segmentation is an open problem. In order to approach this
problem, we propose an automatic technique, named nonlinear technique (NLT), based on a
thresholding method, noise suppression filters, intelligent operators, a clustering strategy and a
binary morphological operator. NLT performance is assessed by Jaccard's similarity index
(JSI) used to compare ...

#### Renal lithiasis detection in uro-computed tomography using a non-parametric technique

(IOP Publishing, 2019)

Renal lithiasis is the pathology that causes nephritic colic, which is one of the most frequent reasons for consultation in emergency medical services. According to the size, location, hardness and number of stones present in the urinary system, usually in the human kidney, it is established to which form of treatment is suitable for the patient. These kidney stones can be analyzed by means of biopsy or imaging modalities such as computed tomography images. This type of images has challenging problems called noise, artifacts and low contrast. In ...

#### Space-occupying lesions identification in mammary glands using a mixed computational strategy

(IOP Publishing, 2019)

Abstract. The mammary pathology can manifest itself in multiple ways and originates spaceoccupying
lesions. The breast cancer is a space-occupying lesion, which is highly prevalent,
especially in women, and worldwide it is one of the leading causes of morbidity and mortality
in this population. The main image modality for breast cancer detection is the magnetic
resonance but this kind of image modality introduces several imperfections that affect the
image quality. Some of these imperfections or problems are: inhomogeneity in the ...

#### Security strategy for vulnerabilities prevention in the development of web applications

(IOP Publishing, 2019)

In recent years, Higher Education Institutions through their Systems departments have
strengthened security for the development of applications on web environment, because of their
vulnerability to possible computer attacks. This research proposes a security strategy to reduce
the risk presented by the web applications developed in the systems department of the Simón
Bolívar University, in San José de Cúcuta, Colombia, based on a diagnosis of the current state
of its security policy compared to other institutions of the department of Norte ...

#### Large cells cancer volumetry in chest computed tomography pulmonary images

(IOP Publishing, 2019)

Lung cancer is the leading oncological cause of death in the world. As for
carcinomas, they represent between 90% and 95% of lung cancers; among them, non-small cell
lung cancer is the most common type and the large cell carcinoma, the pathology on which this
research focuses, is usually detected with the computed tomography images of the thorax.
These images have three big problems: noise, artifacts and low contrast. The volume of the
large cell carcinoma is obtained from the segmentations of the cancerous tumor generated, in a
semi-automatic ...

#### Interest rates calculation in certain ordinary annuities

(IOP Publishing, 2019)

Certain annuities are annuities whose payments occur on fixed dates; while a certain ordinary annuity is one in which payments are made at the end of each established period. The calculation of the interest rate, which governs the certain ordinary annuity, involves the use of a non-analytical equation that requires the application of numerical techniques to obtain the value of the aforementioned rate. The literature indicates that any of these techniques requires one or several numerical values for initialization, which generally are estimated ...

#### Newton-Raphson method initialization for non-analytical equations solution linked to anticipated annuities

(IOP Publishing, 2019)

The series of payments made in equal intervals of time is known, in the world of
financial mathematics, as an annuity. An anticipated annuity is one whose periodic payment
expires at the beginning of the established payment interval. The non-analytical equation that
allows us to calculate the interest rate, linked to the anticipated annuity, can be solved using
several numerical methods, in particular, the numerical method called Newton-Rhapson. The
main problem with this method is its initialization, which requires of one starting point ...

#### Semi-automatic detection of hepatic tumor in computed tomography images

(IOP Publishing, 2019)

In this work, the main purpose is develop a computational segmentation strategy for
liver tumor semiautomatic detection. This strategy considers three-dimensional computed
tomography images and it consists of techniques application that, on the one hand, diminish the
noise and detect the edges of the objects present in those images and, on the other hand, generate
the liver tumor morphology. For this, the sequence of techniques composed of gaussian
smoothing, gradient magnitude, median filter, region growing and binary morphological dilation
are ...

#### Problem solving strategy in the teaching and learning processes of quantitative reasoning

(IOP Publishing, 2019)

The study presents an analysis of Polya's problem-solving strategy used in the training
processes of quantitative reasoning competence in students of the Universidad Simón Bolívar,
San José de Cúcuta, Colombia. The research was based on a descriptive design and had an
intentional sample of 58 students who were studying the sciences and general competencies
elective. For the collection of information, a diagnostic test (pre-test) and a final test (post-test)
were applied, in order to check the incidence of the applied strategy. The results ...

#### Use of computational realistic models for the cardiac ejection fraction calculation

(IOP Publishing, 2019)

Ejection fraction is one of the most useful clinical descriptors to determine the cardiac
function of a subject. For this reason, obtaining the value of this descriptor is of vital importance
and requires high precision. However, in the clinical routine, to generate the mentioned
descriptor value, a geometric hypothesis is assumed, obtaining an approximate value for this
fraction, usually by excess, and which is a dependent-operator. The aim of the present work is
to propose the accurate calculation of the ejection fraction from realistic ...