Semantic reasoning in cognitive networks for heterogeneous wireless mesh systems

The next generation of wireless networks is expected to provide not only higher bandwidths anywhere and at any time but also ubiquitous communication using different network types. However, several important issues including routing, self-configuration, device management, and context awareness have to be considered before this vision becomes reality. This paper proposes a novel cognitive network framework for heterogeneous wireless mesh systems to abstract the network control system from the infrastructure by introducing a layer that separates the management of different radio access networks from the data transmission. This approach simplifies the process of managing and optimizing the networks by using extendable smart middleware that automatically manages, configures, and optimizes the network performance. The proposed cognitive network framework, called FuzzOnto, is based on a novel approach that employs ontologies and fuzzy reasoning to facilitate the dynamic addition of new network types to the heterogeneous network. The novelty is in using semantic reasoning with cross-layer parameters from heterogeneous network architectures to manage and optimize the performance of the networks. The concept is demonstrated through the use of three network architectures: 1) wireless mesh network; 2) long-term evolution (LTE) cellular network; and 3) vehicular ad hoc network (VANET). These networks utilize nonoverlapped frequency bands and can operate simultaneously with no interference. The proposed heterogeneous network was evaluated using ns-3 network simulation software. The simulation results were compared with those produced by other networks that utilize multiple transmission devices. The results showed that the heterogeneous network outperformed the benchmark networks in both urban and VANET scenarios by up to 70% of the network throughput, even when the LTE network utilized a high bandwidth

Bimodal automated carotid ultrasound segmentation using geometrically constrained deep neural networks

For asymptomatic patients suffering from carotid stenosis, the assessment of plaque morphology is an important clinical task which allows monitoring of the risk of plaque rupture and future incidents of stroke. Ultrasound Imaging provides a safe and non-invasive modality for this, and the segmentation of media-adventitia boundaries and lumen-intima boundaries of the Carotid artery form an essential part in this monitoring process. In this paper, we propose a novel Deep Neural Network as a fully automated segmentation tool, and its application in delineating both the media-adventitia boundary and the lumen-intima boundary. We develop a new geometrically constrained objective function as part of the Network's Stochastic Gradient Descent optimisation, thus tuning it to the problem at hand. Furthermore, we also apply a bimodal fusion of amplitude and phase congruency data proposed by us in previous work, as an input to the network, as the latter provides an intensity-invariant data source to the network. We finally report the segmentation performance of the network on transverse sections of the carotid. Tests are carried out on an augmented dataset of 81,000 images, and the results are compared to other studies by reporting the DICE coefficient of similarity, modified Hausdorff Distance, sensitivity and specificity. Our proposed modification is shown to yield improved results on the standard network over this larger dataset, with the advantage of it being fully automated. We conclude that Deep Neural Networks provide a reliable trained manner in which carotid ultrasound images may be automatically segmented, using amplitude data and intensity invariant phase congruency maps as a data source

Clock drawing test digit recognition using static and dynamic features

The clock drawing test (CDT) is a standard neurological test for detection of cognitive impairment. A computerised version of the test promises to improve the accessibility of the test in addition to obtaining more detailed data about the subject's performance. Automatic handwriting recognition is one of the first stages in the analysis of the computerised test, which produces a set of recognized digits and symbols together with their positions on the clock face. Subsequently, these are used in the test scoring. This is a challenging problem because the average CDT taker has a high likelihood of cognitive impairment, and writing is one of the first functional activities to be affected. Current handwritten digit recognition system perform less well on this kind of data due to its unintelligibility. In this paper, a new system for numeral handwriting recognition in the CDT is proposed. The system is based on two complementary sources of data, namely static and dynamic features extracted from handwritten data. The main novelty of this paper is the new handwriting digit recognition system, which combines two classifiers—fuzzy k-nearest neighbour for dynamic stroke-based features and convolutional neural network for static image- based features, which can take advantage of both static and dynamic data. The proposed digit recognition system is tested on two sets of data: first, Pendigits online handwriting digits; and second, digits from the actual CDTs. The latter data set came from 65 drawings made by healthy people and 100 drawings reproduced from the drawings by dementia patients. The test on both data sets shows that the proposed combination system can outperform each classifier individually in terms of recognition accuracy, especially when assessing the handwriting of people with dementi

Automatic classification of facial morphology for medical applications

Facial morphology measurement and classification play important role in the face anthropometry of many medical applications. This usually involves the investigation of medical abnormalities where specific facial features are studied by taking a number of measurements of the facial area under investigation. The measurements are often obtained from the three-dimensional (3D) scans of the faces; however, the measurements are often made manually, which is tedious and time consuming process. Moreover, in gene related studies thousands of measurements may be necessary in order to find statistically significant relationships between facial features and genes. Normative studies, from which typical populous models can be built, also require many measurements. Thus an automatic method to extract morphological measurements and interpret them is desirable. In this article, an automatic method for classification of facial morphology on the basis of a number of geometric measurements obtained automatically from 3D facial scans is presented. Among different facial features the philtrum, which is the vertical groove extending from the nose to the upper lip and the lip area, plays an important role in defining the interaction between the genes and craniofacial anomalies such as, for example, cleft lip and palate. In this paper, geometric features are analysed for their suitability to classify philtrum into three classes previously proposed by medical experts. Moreover, further analysis is conducted to assess the best number of classes to model the underlying data distribution from the point of view of classification accuracy. The obtained classification results are compared with the ground truth manual labelling of 3D face meshes provided by a medical expert. The dataset used for this research is taken from ALSPAC dataset and consists of 1000 3D face meshes. The proposed method achieves classification accuracy of 97% for this data set using the Mean, Minimum and Maximum curvature features in combination

Segmentation of clock drawings based on spatial and temporal features

The Clock Drawing Test (CDT) is an inexpensive and effective measure for early detection of cognitive impairment in the elderly, which is important for timely diagnosis and initiation of appropriate treatment. Currently, medical experts assess the drawings based on their judgement and a number of available scoring systems. An automatic system for assessment of CDT drawings would simultaneously decrease the waiting time for a specialist appointment and improve accessibility of the test to the patients. Published research has only started to address the problem of automatic assessment of CDT drawings and existing systems require user intervention during the segmentation of the CDT drawing into its composing parts, such as numbers and clock hands. In this paper, a new set of temporal and spatial features automatically extracted from the CDT data acquired using a graphics tablet is proposed. Consequently, a Support Vector Machine (SVM) classifier is employed to segment the CDT drawings into their elements, such as numbers and clock hands, on the basis of the extracted features. The proposed algorithm is tested on two data sets, the first set consisting of 65 drawings made by healthy people, and the second consisting of 100 drawings reproduced from actual drawings of dementia patients. The test on both data sets shows that the proposed method outperforms the current state-of-the-art method for CDT drawing segmentation

Context change and triggers for human intention recognition

In human-robot interaction, understanding human intention is important to smooth interaction between humans and robots. Proactive human-robot interactions are the trend. They rely on recognising human intentions to complete tasks. The reasoning is accomplished based on the current human state, environment and context, and human intention recognition and prediction. Many factors may affect human intention, including clues which are difficult to recognise directly from the action but may be perceived from the change in the environment or context. The changes that affect human intention are the triggers and serve as strong evidence for identifying human intention. Therefore, detecting such changes and identifying such triggers are the promising approach to assist in human intention recognition. This paper discusses the current state of art in human intention recognition in human-computer interaction and illustrates the importance of context change and triggers for human intention recognition in a variety of examples

A geometrically constrained multimodal approach for convolutive blind source separation

A novel constrained multimodal approach for convolutive blind source separation is presented which incorporates video information related to geometrical position of both the speakers and the microphones, and the directionality of the speakers into the separation algorithm. The separation is performed in the frequency domain and the constraints are incorporated through a penalty function-based formulation. The separation results show a considerable improvement over traditional frequency domain convolutive BSS systems such as that developed by Parra and Spence. Importantly, the inherent permutation problem in the frequency domain BSS is potentially solve

Feature extraction method for clock drawing test

Recently, the number of elderly persons with dementia has been increasing. In the past, we proposed a dementia evaluation system using daily conversations and developed the system with a conversational robot. However, the current system is not ready for practical use because it can only evaluate time/geographical orientation and short-term memory, and some methods to evaluate other orientations and functions is required as well. In this paper, we discuss a new dementia evaluation system using not only daily conversations but also drawing tests. The authors employed a Clock Drawing Test (CDT) as a new dementia evaluation test and implemented it in a tablet device. This paper discusses a feature extraction and recognition method to distinguish normal cases from dementia cases. After evaluation experiments, the proposed method could recognize 87.6% of the clock drawing images