11 research outputs found

    Classification of epileptic EEG signals based on simple random sampling and sequential feature selection

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    Electroencephalogram (EEG) signals are used broadly in the medical fields. The main applications of EEG signals are the diagnosis and treatment of diseases such as epilepsy, Alzheimer, sleep problems and so on. This paper presents a new method which extracts and selects features from multi-channel EEG signals. This research focuses on three main points. Firstly, simple random sampling (SRS) technique is used to extract features from the time domain of EEG signals. Secondly, the sequential feature selection (SFS) algorithm is applied to select the key features and to reduce the dimensionality of the data. Finally, the selected features are forwarded to a least square support vector machine (LS_SVM) classifier to classify the EEG signals. The LS_SVM classifier classified the features which are extracted and selected from the SRS and the SFS. The experimental results show that the method achieves 99.90, 99.80 and 100 % for classification accuracy, sensitivity and specificity, respectively

    Minimum node degree of k-connected vehicular ad hoc networks in highway scenarios

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    A vehicular ad hoc network (VANET) is a specific type of mobile ad hoc networks (MANETs); it can provide direct or multi-hop vehicle-to-vehicle (V2V), vehicle-to-roadside (V2R), vehicle-to-pedestrian (V2P), and vehicle-to-internet (V2I)communications based on the pre-existing road layouts. The emerging and promising VANET technologies have drawn tremendous attention from the government, academics, and industry over the past few years and have been increasingly available for a large number of cutting edge applications that can be classified into road safety, traffic efficiency, and infotainment categories. Due to the unique characteristics of VANETs, such as high mobility with an organized but constrained pattern, and diverse radio propagation conditions, the conventional researches dedicated for general MANETs cannot be directly applied to VANETs. This paper presents an analytical framework to investigate the minimum node degree of k-connected VANETs, with a homogeneous range assignment in highway scenarios. We simulate the mobility patterns with realistic vehicular traces, model the network topology as a two-path fading geometric random graph, and conduct extensive experiments on the derived analytical results. Through a combination of mathematical modeling and simulations, we derive a probabilistic bound for the minimum node degree of a homogeneous vehicular ad hoc network in highway scenarios. The analytical framework is useful in the study of connectivity and estimation of performance in one-dimensional vehicular ad hoc networks

    Utformning av sidoområden med hänsyn till vägens livscykelkostnad

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    Single vehicle accidents are one of the most common types of accidents that occur on the Swedish road network. Depending on the design of the road, the presence of a crash barrier and embankment on the roadside, the outcome of a roadside collision can lead to serious injuries and even deaths.The aim of this project is to investigate the possibility of improving road safety by designing the optimal roadside area based on the results of a life cycle cost analysis (LCC).The questions that have been answered during the duration of this project are: 1) Describe the current technical solutions for roadside area design and the various barrier types used in Sweden.2) Complete an existing mathematical model that has been developed by Hawzheen Karim, for calculating life-cycle costs for various roadside areas.3) Calculate and compare the life cycle costs for the side area with a barrier and without a barrier. By performing an analysis of the documentation on the current guidelines and rules for shaping the roadside, was it possible to describe the current technical solutions for the formation the roadside as well as the current roadside barriers in use today. A mathematical model for calculating the life cycle costs of different barrier types had already been developed by Hawzheen Karim. This model was supplemented so that it could calculate life-cycle costs of the roadside region with and without a barrier. After the model was completed, an analysis was performed to obtain life-cycle costs of a roadside with and without a barrier.The result showed that there is a clear relationship between the slope inclination, fill height, and the rate at which the costs rise. This breakpoint is highly dependent on several factors such as the price of land, the presence of bedrock in the construction process and if the ballast material needs to be treated. A flatter slope causes an increase in both the volume of material and the area of land that needs to be obtained, while a steep slope with a barrier may result in higher costs to society due to fatal collisions with the barrier and higher operating and maintenance costs.Singelolyckor är en av de vanligaste olyckstyperna som förekommer på det svenska vägnätet. Beroende på utformningen av vägen, förekomsten av vägräcke och slänten på sidoområdet kan förloppet av en avkörningsolycka leda till svåra skador och även dödsfall. Syftet med detta projektet är att undersöka möjligheten att öka trafiksäkerheten genom att utforma det optimala sidoområdet baserat på en livscykelkostnadsanalys (LCC-analys).De frågeställningar som har besvarats under projektets utförande är: 1) Beskriv de nuvarande tekniska lösningar för sidoområdets utformning och de olika typer av räcken som används i Sverige.2) Komplettera en befintlig matematisk modell som har tagits fram av Hawzheen Karim, för beräkningar av livscykelkostnader för olika sidoområden.3) Beräkna och jämför livscykelkostnader för sidoområdet med räcken och utan räcken. Genom att utföra en dokumentanalys på de nuvarande riktlinjer och bestämmelser kunde alla nuvarande tekniska lösningar för sidområdets utformning och olika räckestyper beskrivas. De nuvarande tekniska lösningar som finns för att utforma sidoområden är både enkla och mycket effektiva, och riktlinjerna som finns för utformning av sidoområden är också omfattande och lätta att förstå.En matematisk modell för beräkning av livscykelkostnader av olika räckestyper hade redan tagits fram av Hawzheen Karim. Denna model kompletterades för att kunna användas både på sidoområdet med och utan räcken. För att få fram de samhällsekonomiska kostnaderna var det nödvändigt att använda STRADA (Swedish Traffic Accident Data Acquisition) för att räkna ut hur ofta avkörnings- och påkörningsolyckor i räcken leder till skador och dödsfall vilket blir stora kostnader för samhället. Efter att modellen kompletterats kunde en analys utföras för att få fram livscykelkostnader för ett sidoområde med och utan räcken. Resultatet redovisades grafiskt och skärningspunkterna visade den fyllnadhöjd då det blev mer lönsamt att installera vägräcken med en brant slänt istället för att bygga en flackare slänt. Resultatet visade att det finns ett tydligt samband mellan släntens lutning, fyllnadshöjden och graden till vilken kostnaderna stiger. Denna brytpunkt är mycket beroende på en rad faktorer så som markpriset, förekomsten av berggrund i området och om friktionsmaterial behöver behandlas. En flackare slänt medför en ökning av både volymerna av material samt area mark som behöver inlösas, medans en brant slänt med räcken kan medföra högre samhällsekonomiska kostnader på grund av påkörningsolyckor med räcken samt högre drift-och underhållskostnader

    Multiscale entropy algorithms and their applications in cardiac disease discrimination

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    In recent years, the number of cardiac disease patients has been increasing. Modern medical research has shown that the complexity of electrocardiogram (ECG) signals is related to cardiovascular diseases. This paper investigates the difference in complexity of ECG data from the people with different cardiovascular diseases, such as atrial fibrillation (AF), ventricular arrhythmia (VA) and congestive heart failure (CHF). The empirical mode decomposition (EMD) and multiscale entropy method are used to analyze the ECG data, and a mathematical model established by a support vector machine is used to identify different diseases. The accuracy recognition rate of the AF recognition is 96.25%, and that of the CHF and VA reach 90.26% and 92.20%, respectively. The experimental results show that the recognition method proposed in this paper is successful

    A T-wave alternans assessment method based on least squares curve fitting technique

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    T-wave alternans (TWA) is hypothesized to be related with patients at an increased risk for ventricular arrhythmias. A novel TWA assessment method based on least squares curve fitting techniques (LSCF) is presented in this paper. Real clinical ECG recordings and simulated ECG signals containing additive TWAs and noise are used to test the efficiency of the LSCF. The results are also compared with those by the Modified Moving Average(MMA) algorithm. The experimental results demonstrate that the LSCF is efficiency and promising in detecting and measuring TWAs

    Experimental Investigation of High Speed Cross-Domain Vehicles with Hydrofoil

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    Unmanned equipment, such as unmanned underwater vehicles (UUVs) and unmanned surface vehicles (USVs), are widely used in marine science for underwater observation, rescue, military purposes, etc. However, current vehicles are not applicable in complex cross-domain scenarios, because they can only perform well in either surface navigation or underwater diving. This paper deals with the design and fabrication of a cross-domain vehicle (CDV) with four hydrofoils that can both navigate at high speed on the surface, like a USV and dive silently underwater, like a UUV. The CDV’s propulsion is provided by a water jet propeller and its dive is achieved by a vertical propeller. The effect of hydrofoils and the performance of the CDV were tested and characterized in experiments, which showed that the hydrofoils improved the stability and surface sailing speed of the CDV. The maximum speed of the CDV was up to 14 kn, which is the highest of its kind according to current knowledge. This work confirmed the feasibility of high-performance CDVs and provided useful information for further improvements to the design

    Experimental Investigation of High Speed Cross-Domain Vehicles with Hydrofoil

    No full text
    Unmanned equipment, such as unmanned underwater vehicles (UUVs) and unmanned surface vehicles (USVs), are widely used in marine science for underwater observation, rescue, military purposes, etc. However, current vehicles are not applicable in complex cross-domain scenarios, because they can only perform well in either surface navigation or underwater diving. This paper deals with the design and fabrication of a cross-domain vehicle (CDV) with four hydrofoils that can both navigate at high speed on the surface, like a USV and dive silently underwater, like a UUV. The CDV's propulsion is provided by a water jet propeller and its dive is achieved by a vertical propeller. The effect of hydrofoils and the performance of the CDV were tested and characterized in experiments, which showed that the hydrofoils improved the stability and surface sailing speed of the CDV. The maximum speed of the CDV was up to 14 kn, which is the highest of its kind according to current knowledge. This work confirmed the feasibility of high-performance CDVs and provided useful information for further improvements to the design

    Experimental Investigation of High Speed Cross-Domain Vehicles with Hydrofoil

    No full text
    Unmanned equipment, such as unmanned underwater vehicles (UUVs) and unmanned surface vehicles (USVs), are widely used in marine science for underwater observation, rescue, military purposes, etc. However, current vehicles are not applicable in complex cross-domain scenarios, because they can only perform well in either surface navigation or underwater diving. This paper deals with the design and fabrication of a cross-domain vehicle (CDV) with four hydrofoils that can both navigate at high speed on the surface, like a USV and dive silently underwater, like a UUV. The CDV's propulsion is provided by a water jet propeller and its dive is achieved by a vertical propeller. The effect of hydrofoils and the performance of the CDV were tested and characterized in experiments, which showed that the hydrofoils improved the stability and surface sailing speed of the CDV. The maximum speed of the CDV was up to 14 kn, which is the highest of its kind according to current knowledge. This work confirmed the feasibility of high-performance CDVs and provided useful information for further improvements to the design
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