Magnus Johnsson

Review: Application of artificial neural networks in the diagnosis of urological dysfunctions

In this article, we evaluate the work out of some artificial neural network models as tools for support in the medical diagnosis of urological dysfunctions. We develop two types of unsupervised and one supervised neural network. This scheme is meant to help the urologists in obtaining a diagnosis for complex multi-variable diseases and to reduce painful and costly medical treatments since neurological dysfunctions are difficult to diagnose. The clinical study has been carried out using medical registers of patients with urological dysfunctions. The proposal is able to distinguish and classify between ill and healthy patients.

Predicting seminal quality with artificial intelligence methods

Fertility rates have dramatically decreased in the last two decades, especially in men. It has been described that environmental factors, as well as life habits, may affect semen quality. Artificial intelligence techniques are now an emerging methodology as decision support systems in medicine. In this paper we compare three artificial intelligence techniques, decision trees, Multilayer Perceptron and Support Vector Machines, in order to evaluate their performance in the prediction of the seminal quality from the data of the environmental factors and lifestyle. To do that we collect data by a normalized questionnaire from young healthy volunteers and then, we use the results of a semen analysis to asses the accuracy in the prediction of the three classification methods mentioned above. The results show that Multilayer Perceptron and Support Vector Machines show the highest accuracy, with prediction accuracy values of 86% for some of the seminal parameters. In contrast decision trees provide a visual and illustrative approach that can compensate the slightly lower accuracy obtained. In conclusion artificial intelligence methods are a useful tool in order to predict the seminal profile of an individual from the environmental factors and life habits. From the studied methods, Multilayer Perceptron and Support Vector Machines are the most accurate in the prediction. Therefore these tools, together with the visual help that decision trees offer, are the suggested methods to be included in the evaluation of the infertile patient.

Ikaros: Building cognitive models for robots

The Ikaros project started in 2001 with the aim of developing an open infrastructure for system-level brain modeling. The system has developed into a general tool for cognitive modeling as well as robot control. Here we describe the main parts of the Ikaros system and how it has been used to implement various cognitive systems and to control a number of different robots ranging from robot arms and hands to active vision systems and mobile robots.

Neural network models of haptic shape perception

Three different models of tactile shape perception inspired by the human haptic system were tested using an 8 d.o.f. robot hand with 45 tactile sensors. One model is based on the tensor product of different proprioceptive and tactile signals and a self-organizing map (SOM). The two other models replace the tensor product operation with a novel self-organizing neural network, the Tensor-Multiple Peak Self-Organizing Map (T-MPSOM). The two T-MPSOM models differ in the procedure employed to calculate the neural activation. The computational models were trained and tested with a set of objects consisting of hard spheres, blocks and cylinders. All the models learned to map different shapes to different areas of the SOM, and the tensor product model as well as one of the T-MPSOM models also learned to discriminate individual test objects.

Sense of Touch in Robots With Self-Organizing Maps

We review a number of self-organizing-robot systems that are able to extract features from haptic sensory information. They are all based on self-organizing maps (SOMs). First, we describe a number of systems based on the three-fingered-robot hand, i.e., the Lund University Cognitive Science (LUCS) Haptic-Hand II, that successfully extracts the shapes of objects. These systems explore each object with a sequence of grasps while superimposing the information from individual grasps after cross-coding proprioceptive information for different parts of the hand and the registrations of tactile sensors. The cross-coding is done by employing either the tensor-product operation or a novel self-organizing neural network called the tensor multiple peak SOM (T-MPSOM). Second, we present a system based on proprioception that uses an anthropomorphic robot hand, i.e., the LUCS haptic-hand III. This system is able to distinguish objects both according to shape and size. Third, we present systems that are able to extract and combine the texture and hardness properties from explored materials.

Semen Parameters Can Be Predicted from Environmental Factors and Lifestyle Using Artificial Intelligence Methods

ABSTRACT Fertility rates have dramatically decreased in the last two decades, especially in men. It has been described that environmental factors as well as life habits may affect semen quality. In this paper we use artificial intelligence techniques in order to predict semen characteristics resulting from environmental factors, life habits, and health status, with these techniques constituting a possible decision support system that can help in the study of male fertility potential. A total of 123 young, healthy volunteers provided a semen sample that was analyzed according to the World Health Organization 2010 criteria. They also were asked to complete a validated questionnaire about life habits and health status. Sperm concentration and percentage of motile sperm were related to sociodemographic data, environmental factors, health status, and life habits in order to determine the predictive accuracy of a multilayer perceptron network, a type of artificial neural network. In conclusion, we have developed an artificial neural network that can predict the results of the semen analysis based on the data collected by the questionnaire. The semen parameter that is best predicted using this methodology is the sperm concentration. Although the accuracy for motility is slightly lower than that for concentration, it is possible to predict it with a significant degree of accuracy. This methodology can be a useful tool in early diagnosis of patients with seminal disorders or in the selection of candidates to become semen donors.

2012 Special Issue: Using GNG to improve 3D feature extraction-Application to 6DoF egomotion

Several recent works deal with 3D data in mobile robotic problems, e.g. mapping or egomotion. Data comes from any kind of sensor such as stereo vision systems, time of flight cameras or 3D lasers, providing a huge amount of unorganized 3D data. In this paper, we describe an efficient method to build complete 3D models from a Growing Neural Gas (GNG). The GNG is applied to the 3D raw data and it reduces both the subjacent error and the number of points, keeping the topology of the 3D data. The GNG output is then used in a 3D feature extraction method. We have performed a deep study in which we quantitatively show that the use of GNG improves the 3D feature extraction method. We also show that our method can be applied to any kind of 3D data. The 3D features obtained are used as input in an Iterative Closest Point (ICP)-like method to compute the 6DoF movement performed by a mobile robot. A comparison with standard ICP is performed, showing that the use of GNG improves the results. Final results of 3D mapping from the egomotion calculated are also shown.

Review: Using support vector machines in diagnoses of urological dysfunctions

Urinary incontinence is one of the largest diseases affecting between 10% and 30% of the adult population and an increase is expected in the next decade with rising treatment costs as a consequence. There are many types of urological dysfunctions causing urinary incontinence, which makes cheap and accurate diagnosing an important issue. This paper proposes a support vector machine (SVM) based method for diagnosing urological dysfunctions. 381 registers collected from patients suffering from a variety of urological dysfunctions have been used to ensure the (generalization) performance of the decision support system. Moreover, the robustness of the proposed system is examined by fivefold cross-validation and the results show that the SVM-based method can achieve an average classification accuracy at 84.25%.

A haptic system for the lucs haptic hand I

This paper describes a system for haptic object categorization. It consists of a robotic hand, the LUCS Haptic Hand I, together with software modules that to some extent simulate the functioning of the primary and the secondary somatosensory cortices. The haptic system is the first one in a project at LUCS aiming at studying haptic perception. In the project, several robotic hands together with cognitive computational models of the corresponding human neurophysiological systems will be built. The haptic system was trained and tested with a set of objects consisting of balls and cubes, and the activation in the modules corresponding to secondary somatosensory cortex was studied. The results suggest that the haptic system is capable of categorization of objects according to size, if the shapes of the objects are restricted to spheres and cubes.

Review Article: Modelling of urological dysfunctions with neurological etiology by means of their centres involved

Urinary incontinence is a considerable problem which is clearly reflected in the number of patients affected by it. Moreover, it is extremely difficult to obtain an accurate diagnosis as the urinary incontinence very often is related to the neurological system. In this article a model with capabilities for urological diagnosing is proposed. This model is specialized towards the diagnosis of urological dysfunctions with neurological etiology. For this reason the model explores all the neural centres involved in both the urological phases, voiding and micturition. Once these centres have been studied it becomes possible to establish a direct relation between neural centres which present an anomalous functioning and neurological dysfunctions.