46 research outputs found
Intensity Adjustment and Noise Removal for Medical Image Enhancement
Introduction: Image contrast enhancement is an image processing method in which the output image
has high quality display. Medical images have prominent role in modern diagnosis; therefore, this
study aimed to enhance the quality of medical images in order to help radiologists and surgeons in
finding abnormal areas.
Method: The methods used in this study to enhance medical images quality are categorized into two
groups; intensity adjustment and noise removal. Intensity adjustment methods including techniques for
mapping image intensity values to the new domain. The second group including methods to remove
noise from the images. Medical images used in this study including images of spine, brain, lung and
breast.
Results: The results were analyzed based on five criteria including the number of detected edges,
PCNR, Image Quality Index, AMBE and visual quality that the number of detected edges in images of
spine, brain, lungs and breast were 6465, 10305, 16266 and 13509, respectively.
Conclusion: The results show that the methods with intensity adjustment technique have better
performance in criteria such as the number of detected edges and image visual assessment. However,
the other method include in noise removal technique perform more effectively in PCNR, Image
Quality Index and AMBE measure
A Novel Memetic Feature Selection Algorithm
Feature selection is a problem of finding efficient
features among all features in which the final feature set can improve accuracy and reduce complexity. In feature selection algorithms search strategies are key aspects. Since feature selection is an NP-Hard problem; therefore heuristic algorithms have been studied to solve this problem.
In this paper, we have proposed a method based on memetic algorithm to find an efficient feature subset for a classification problem. It incorporates a filter method in the genetic algorithm to improve classification performance and accelerates the search in identifying core feature subsets. Particularly, the method adds or deletes a feature from a candidate feature subset based on the multivariate feature information. Empirical study on commonly data sets of the university of California, Irvine shows that the proposed method outperforms existing methods
Modified Histogram Segmentation Bi-Histogram Equalization
Image enhancement is the widespread application of the image
processing field. Conventional methods which are studied in contrast
enhancement such as Histogram Equalization (HE) have not satisfactory results
on many different low contrast images and they also cannot automatically handle
different images. These problems result of specifying parameters manually in
order to produce high contrast images. In this paper, Modified Histogram
Segmentation Bi-Histogram Equalization (MHSBHE) is proposed. In this study,
histogram is modified before segmentation to improve the input image contrast.
The proposed method accomplishes multi goals of preserving brightness,
retaining the shape features of the original histogram and controlling excessive
enhancement rate, suiting for applications of consumer electronics. By this
simulation results, it has been shown that in terms of visual assessment, Absolute
Mean Brightness Error (AMBE), Peak Signal-To-Noise (PSNR) and average
information content (entropy) the proposed method has better results compared
to literature methods. The proposed method enhances the natural appearance of
images especially in no static range images and the improved image is helpful in
generation of the consumer electronic
Hyper-Heuristic Image Enhancement (HHIE): A Reinforcement Learning Method for Image Contrast Enhancement
Conventional contrast enhancement methods such as Histogram
Equalization (HE) have not acceptable results on many different low contrast
images and they also cannot handle various images in automatically way. These
problems result of specifying parameters manually in sake of producing high
contrast images. We proposed an automatic image contrast enhancement on
Hyper-Heuristic. In this study, simple exploiters are proposed to improve the
contrast of current image. To select these exploiters appropriately, reinforcement
learning is proposed. This selection is based on functional history of these
exploiters. Having multi aim of preserving brightness, retaining the shape
features of the original histogram and controlling on the rate of over-enhancement
are the achievement of the proposed method. These objectives are suitable for the
application of consumer electronics. By this simulation results, it has been shown
that in terms of visual assessment, Peak Signal to Noise (PSNR) and Absolute
Mean Brightness Error (AMBE). This study is superior to literature methods
Comparison of the Decision Tree Models to Intelligent Diagnosis of Liver Disease
Background:
Liver is one of the vital organs of human body and its health is of utmost importance for our survival.
Automatic classification instruments, as a diagnostic tool, help to reduce the working load of doctors. But
the concern is that, liver diseases are not easily diagnosed and there are many causes and factors related to
them. The purpose of this research is to compare the decision tree models to intelligent diagnosis of liver
disease. Intelligent diagnosis models used in this research are QUEST, C5.0, CRT and CHAID.
Material and Methods:
Data were collected from the records of 583 patients in the North East of Andhra Pradesh, India. Four tree
models were compared by the specificity, sensitivity, accuracy, and area under ROC curve.
Results:
The accuracy of the classification tree models; QUEST, C5.0, CRT, and CHAID were 73%, 71%, 75%, and
86% respectively.
Conclusion:
CHAID model was considered as the best model with the highest precision. Therefore; CHAID model can
be proposed in the diagnosis of the liver disease. This paper is invaluable in terms of research activities in
the field of health and it is especially important in the allocation of health resources for risky people
A Rule Based Classification Model to Predict Colon Cancer Survival
Introduction: Colon cancer is the second most common cancer in the world and fourth most common
cancer in both sexes in Iran, whose % 8.12 of all cancers in the covers. Predict the outcome of cancer and
basic clinical data about it is very important. Data mining techniques can be used to predict cancer outcome.
In our country, data mining studies on colon cancer, not covered as lung or breast cancers. It seems can be
with identify factors influencing on survival and modify them, increased survival of colon cancer patients.
Then according to high rates of colon cancer and the benefits of data mining to predict survival, in this study
examined factors influencing on the survival of these patients.
Materials and Methods: We use a dataset with four attributes that include the records of 570 patients in
which 327 Patients (57.4%) and 243 (42.6%) patients were males and females respectively. Trees Random
Forest (TRF), AdaBoost (AD), RBF Network (RBFN), and Multilayer Perceptron (MLP) machine learning
techniques with 10-cross fold technique were used with the proposed model for the prediction of colon
cancer survival. The performance of machine learning techniques were evaluated with accuracy, precision,
sensitivity, specificity, and area under ROC curve.
Results: Out of 570 patients, 338 patients and 232 patients were alive and dead respectively. In this Study,
at first sight it seems that among this techniques, Trees Random Forest (TRF) technique showed better
results in comparison to other techniques (AD, RBFN and MLP). The accuracy, sensitivity, specificity and
the area under ROC curve of TRF are 0.76, 0.808, 0.70 and 0.83, respectively.
Conclusions: In this study seems that Trees Random Forest model (TRF) which is a rule based
classification model was the best model with the highest level of accuracy. Therefore, this model is
recommended as a useful tool for colon cancer survival prediction as well as medical decision making