120 results on '"Martin Masek"'
Search Results
52. A Genetic Programming Framework for Novel Behaviour Discovery in Air Combat Scenarios
- Author
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Luke Kelly, Martin Masek, Chiou Peng Lam, Michael Papasimeon, and Lyndon Benke
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Fitness function ,Ideal (set theory) ,Computer science ,business.industry ,Genetic programming ,Machine learning ,computer.software_genre ,Domain (software engineering) ,Set (abstract data type) ,Range (mathematics) ,Tree structure ,Artificial intelligence ,Electronic warfare ,business ,computer - Abstract
Behaviour trees offer a means to systematically decompose a behaviour into a set of steps within a tree structure. Genetic programming, which has at its core the evolution of tree-like structures, thus presents an ideal tool to identify novel behaviour patterns that emerge when the algorithm is guided by a set fitness function. In this paper, we present our framework for novel behaviour discovery using evolved behaviour trees, with some examples from the beyond-visual range air combat domain where distinct strategies emerge in response to modelling the effects of electronic warfare.
- Published
- 2021
53. Model Synthesis and Stochastic Automated Verification of Systems-of-Systems Dynamic Architectures
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Martin Masek, Ahmad Mohsin, Valdemar Vicente Graciano Neto, and Naeem Khalid Janjua
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Model checking ,System of systems ,Software ,business.industry ,Computer science ,Distributed computing ,Probabilistic CTL ,Control reconfiguration ,Model synthesis ,Markov decision process ,Software architecture ,business - Abstract
Software intensive Systems-of-Systems (SoS) are complex alliances of autonomous Constituent Systems (CSs) formed at a large scale to achieve a common objective. As such the CSs are operationally and managerially independent and geographically dispersed which generate emergent behaviors to achieve SoS missions through collective dynamics. Therefore, architectural modeling and analysis of a resulting SoS is pivotal to avoid stochastic architectural arrangements that can lead to undesired behaviors, systems outages, losses and non-conformance of core Quality Attributes (QAs) such as performance and reliability. In this research, we propose a formally founded approach for stochastic synthesis and automated verification of SoS architectural models to predict the impact of dynamic architectural changes on QAs at runtime. At first, we provide Hybrid Stochastic Formalism (HSF) based on Process Algebras (PAs) to model the stochastic SoS software architecture. At the architectural level, non-determinism is dealt with by treating HSF as Markov Decision Process (MDP). The SoS modeled with MDP is then verified against certain system properties using model checking through Probabilistic Computation Tree Logic (PCTL) operators. The effectiveness of our approach is evaluated through a fire monitoring and emergency response SoS to predict the impact of dynamic reconfiguration on QAs. The experimental results show that our method helps to assess different architectural configurations that support design choices to achieve missions without compromising quality.
- Published
- 2020
54. Optimal sizing and energy scheduling of grid-supplemented solar PV systems with battery storage: Sensitivity of reliability and financial constraints
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Aakash Hassan, Yasir M. Al-Abdeli, Octavian Bass, and Martin Masek
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Finance ,Power management ,business.industry ,Computer science ,Mechanical Engineering ,Reliability (computer networking) ,Photovoltaic system ,Building and Construction ,Grid ,Pollution ,Industrial and Manufacturing Engineering ,Sizing ,General Energy ,Sensitivity (control systems) ,Electrical and Electronic Engineering ,business ,Baseline (configuration management) ,Energy (signal processing) ,Civil and Structural Engineering - Abstract
Establishing reliable, clean, and inexpensive solar PV systems is a complex interplay between the level of reliability (LPSP), financial constraints, and CO2 emissions. This paper investigates the impact of these factors on stand-alone (SA) and grid-supplemented (GS) solar PV systems over multiple seasons. The research uses established hardware models, detailed power management strategies as well as realistic Australian grid tariffs and Genetic Algorithms to find the minimum Cost of Energy (COE) subject to LPSP and financial constraints. The developed power management strategies are also tested experimentally on a real solar PV system. The results indicate that the grid-supplemented system yields 30% lower COE compared to the stand-alone at baseline (LPSP
- Published
- 2022
55. Sleep monitor: A tool for monitoring and categorical scoring of lying position using 3D camera data
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Bas Jansen, Cameron Tranthim-Fryer, Kevin Baptist, Martin Masek, and Chiou Peng Lam
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lcsh:Computer software ,business.industry ,Computer science ,Interface (computing) ,Body position ,030218 nuclear medicine & medical imaging ,Computer Science Applications ,03 medical and health sciences ,0302 clinical medicine ,Software ,lcsh:QA76.75-76.765 ,3d camera ,Computer vision ,Artificial intelligence ,Sleep (system call) ,Session (computer science) ,business ,Lying ,Categorical variable ,030217 neurology & neurosurgery - Abstract
We present a software package for analysing body positions of a subject when they are lying or sleeping in their bed. The software is designed to interface to inexpensive sensors, such as the Microsoft Kinect, and is thus suitable for monitoring at the subjects own home, rather than a dedicated sleep lab. The system is invariant to bed clothing and levels of ambient lighting. Analysis time for a single night session is under five minutes, a significant improvement over the 30–60 min analysis time reported in the literature. Keywords: Lying position, Body position, Automated analysis
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- 2018
56. Performance Evaluation in Image Processing.
- Author
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Michael A. Wirth, Matteo Fraschini, Martin Masek, and Michel Bruynooghe
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- 2006
- Full Text
- View/download PDF
57. Improving mastery of fractions by blending video games into the Math classroom
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Stephen Corcoran, Julie Boston, Martin Masek, and Chiou Peng Lam
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Multimedia ,Computer science ,Teaching method ,05 social sciences ,Virtual game ,ComputingMilieux_PERSONALCOMPUTING ,050301 education ,Diagnostic test ,050801 communication & media studies ,Teaching program ,Mastery learning ,Mathematics curriculum ,computer.software_genre ,Computer Science Applications ,Education ,Blended learning ,0508 media and communications ,0503 education ,Competence (human resources) ,computer - Abstract
Concepts from the Australian mathematics curriculum on fractions were used as core elements to design three computer games. In each game, the concepts were presented in the form of tangible puzzles, customized to a difficulty level based on student capability. The games were integrated into a single virtual game world, and a fantasy story was used to help build a compelling experience. Five Year 6 classes were used to evaluate the game over four weeks. Three of the classes were provided with the games, and two served as a control. Both the intervention and control groups also covered fractions in class as part of the regular teaching program, consisting of instructor led content combined with access to online resources and activities. Participants completed a diagnostic test before the trial, and again at the end, designed to assess competence in the fractions concepts targeted by the game. Results show that on average students who had access to the game in addition to the regular teaching scored higher than control group students. In particular, looking at just students who started with a lower level of fractions skills, greater improvement was seen in those that had access to the game.
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- 2017
58. Utility of cardiac CT for evaluating delayed contrast enhancement in dilated cardiomyopathy
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David Ambroz, Jan Daneš, Lukas Lambert, Josef Marek, Petr Kuchynka, Martin Masek, Tomas Palecek, Aleš Linhart, and Vladimir Cerny
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Adult ,Cardiomyopathy, Dilated ,Male ,medicine.medical_specialty ,Endomyocardial fibrosis ,Contrast Media ,030204 cardiovascular system & hematology ,Sensitivity and Specificity ,030218 nuclear medicine & medical imaging ,Cohort Studies ,Ventricular Dysfunction, Left ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Myocardial scarring ,Humans ,Medicine ,Prospective Studies ,cardiovascular diseases ,Prospective cohort study ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Dilated cardiomyopathy ,Gold standard (test) ,Middle Aged ,Endomyocardial Fibrosis ,Image Enhancement ,musculoskeletal system ,medicine.disease ,Magnetic Resonance Imaging ,Heart failure ,cardiovascular system ,Cardiology ,Female ,Myocardial fibrosis ,Radiology ,medicine.symptom ,Tomography, X-Ray Computed ,Cardiology and Cardiovascular Medicine ,business - Abstract
The presence of myocardial fibrosis is associated with adverse outcome in dilated cardiomyopathy (DCM). Delayed contrast-enhanced cardiac magnetic resonance (DE-CMR) currently represents the gold standard in noninvasive evaluation of myocardial scarring. However, a significant number of patients are unable to undergo DE-CMR study for various reasons. We sought to determine the diagnostic accuracy of cardiac CT (CCT) compared with CMR in the investigation of the presence of delayed contrast enhancement (DCE) in subjects with DCM. We prospectively enrolled 17 consecutive patients with DCM, who were initially referred to our institution because of recently manifested heart failure due to unexplained left ventricular systolic dysfunction. In all subjects, CCT and DE-CMR were performed within 1 week. CCT and DE-CMR showed satisfactory agreement in detecting DCE (agreement in 82% cases, κ = 0.56) with 50% sensitivity, 100% specificity, and a positive predictive value of 100%. CCT may be a valuable method for detecting DCE in patients with DCM. CCT thus might be considered as an alternative method to DE-CMR in the assessment of the presence and extent of myocardial fibrosis in subjects who are not suitable for DE-CMR examination.
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- 2016
59. Comparison of routine contrast‑enhanced computed tomography with late gadolinium enhancement cardiac magnetic resonance imaging in the detection of myocardial pathology
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David Ambroz, Martin Masek, Tomáš Paleček, Lukas Lambert, Jan Habasko, Josef Marek, Vladimir Cerny, Andrea Burgetova, Petr Kuchynka, and Barbara A. Danek
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Adult ,Male ,Pathology ,medicine.medical_specialty ,Heart Diseases ,media_common.quotation_subject ,Contrast Media ,Computed tomography ,Gadolinium ,Sensitivity and Specificity ,Cardiac magnetic resonance imaging ,Medicine ,Late gadolinium enhancement ,Contrast (vision) ,Humans ,media_common ,Aged ,medicine.diagnostic_test ,Hypoattenuation ,Myocardial tissue ,business.industry ,Myocardium ,Magnetic resonance imaging ,Heart ,Gold standard (test) ,Middle Aged ,Magnetic Resonance Imaging ,Female ,Cardiology and Cardiovascular Medicine ,business ,Tomography, X-Ray Computed - Abstract
Bacground: Cardiac magnetic resonance imaging (MRI) represents the gold standard in noninvasive evaluation of myocardial tissue. However, some patients are unable to undergo cardiac MRI due to a variety of reasons. Aims: We sought to determine the diagnostic accuracy of routinely performed contrast‑enhanced computed tomography (CECT) compared with cardiac MRI in the evaluation of myocardial tissue. Methods: We retrospectively evaluated 96 consecutive patients (mean [SD] age, 51 [15] years; 41 women) who underwent both CECT and cardiac MRI within 30 days. All CECT scans that visualized the entire heart were analyzed, regardless of the indication for and protocol of the procedure. The presence of late gadolinium enhancement on cardiac MRI was compared with the finding of myocardial hypoattenuation on computed tomography scans. Results: With cardiac MRI as the gold standard, CECT revealed a per‑patient sensitivity of 66%, specificity of 89%, positive predictive value of 75%, negative predictive value of 84%, and accuracy of 81%. Per‑segment sensitivity was 54%; specificity, 98%; positive predictive value, 76%; negative predictive value, 94%; and accuracy, 92%. Conclusions: Our study suggests that routinely performed CECT has high specificity, but only moderate sensitivity, compared with cardiac MRI in the evaluation of myocardial tissue. This result supports the recommendation that all CECT scans that visualize the entire heart should be analyzed for myocardial tissue pathology.
- Published
- 2019
60. A simheuristic approach for evolving agent behaviour in the exploration for novel combat tactics
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Martin Masek, Lyndon Benke, Chiou Peng Lam, Michael Papasimeon, and Luke Kelly
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Statistics and Probability ,Control and Optimization ,Computer science ,Simheuristics ,Strategy and Management ,0211 other engineering and technologies ,02 engineering and technology ,Stochastic combinatorial optimization ,Management Science and Operations Research ,Finite state machines ,computer.software_genre ,Machine learning ,Task (project management) ,03 medical and health sciences ,Intelligent agent ,0302 clinical medicine ,Military tactics ,ddc:330 ,Global optimization ,Sequence ,021103 operations research ,Finite-state machine ,business.industry ,lcsh:Mathematics ,Military simulation ,Multiagent simulations ,Genetic algorithms ,lcsh:QA1-939 ,Identification (information) ,030221 ophthalmology & optometry ,Artificial intelligence ,business ,computer - Abstract
The automatic generation of behavioural models for intelligent agents in military simulation and experimentation remains a challenge. Genetic Algorithms are a global optimization approach which is suitable for addressing complex problems where locating the global optimum is a difficult task. Unlike traditional optimisation techniques such as hill-climbing or derivatives-based methods, Genetic Algorithms are robust for addressing highly multi-modal and discontinuous search landscapes. In this paper, we outline a simheuristic GA-based approach for automatic generation of finite state machine based behavioural models of intelligent agents, where the aim is the identification of novel combat tactics. Rather than evolving states, the proposed approach evolves a sequence of transitions. We also discuss workable starting points for the use of Genetic Algorithms for such scenarios, shedding some light on the associated design and implementation difficulties. Keywords: Simheuristics, Genetic algorithms, Multiagent simulations, Stochastic combinatorial optimization, Finite state machines
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- 2019
61. A rare case of regressively changed lipomatous hypertrophy of the interatrial septum presenting with anemia and recurrent fever
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David Zogala, Aleš Linhart, Tomas Palecek, Vladimir Cerny, Martin Masek, Eduard Nemecek, Ivana Vitkova, Zuzana Rucklova, Daniel Rob, and Petr Kuchynka
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Pathology ,medicine.medical_specialty ,Fever ,Heart Diseases ,Anemia ,030204 cardiovascular system & hematology ,Pathology and Forensic Medicine ,Lesion ,03 medical and health sciences ,0302 clinical medicine ,medicine.artery ,Ascending aorta ,Biopsy ,medicine ,Humans ,Lipomatosis ,Pathological ,Aged ,Atrial Septum ,medicine.diagnostic_test ,business.industry ,Hypertrophy ,General Medicine ,medicine.disease ,Lipomatous hypertrophy ,medicine.anatomical_structure ,Recurrent fever ,030220 oncology & carcinogenesis ,Female ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Interatrial septum - Abstract
Lipomatous hypertrophy of the interatrial septum (LHIS) is characterized by excessive accumulation of adipose tissue within some segments of the interatrial septum. Only one published case so far describes fever as a presenting feature of LHIS. On the other hand, systemic symptoms including anemia and fever are well-known clinical presentations of cardiac myxomas. We report an unusual case of a 79-year-old woman who was thoroughly but unsuccessfully investigated for recurrent fever and anemia in several specialized departments over the course of 4 years. Computed tomography scan showed a pathological mass localized in the interatrial septum and spreading to ascending aorta. Histological analysis of the biopsy samples from surgery revealed the unexpected diagnosis of regressively changed LHIS. We discuss the clinical and pathologic features of this lesion suggesting that its regressive changes may be associated with inflammation and can cause systemic symptoms such as fever and anemia.
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- 2016
62. Dystrophic calcification of the interventricular septum mimicking cardiac tumour and role of multimodality imaging
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Petr Kuchynka, Iveta Sotolova, Martin Masek, Lukas Lambert, and Tomas Palecek
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Pathology ,medicine.medical_specialty ,business.industry ,Calcinosis ,Ventricular Septum ,General Medicine ,medicine.disease ,Multimodal Imaging ,Heart Neoplasms ,Heart neoplasms ,medicine.anatomical_structure ,Text mining ,Dystrophic calcification ,medicine ,Medical imaging ,Humans ,Radiology, Nuclear Medicine and imaging ,Interventricular septum ,Cardiology and Cardiovascular Medicine ,business - Published
- 2020
63. Discovering Emergent Agent Behaviour with Evolutionary Finite State Machines
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Lyndon Benke, Michael Papasimeon, Chiou Peng Lam, Luke Kelly, and Martin Masek
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Finite-state machine ,Theoretical computer science ,Computer science ,Evolutionary algorithm ,02 engineering and technology ,computer.software_genre ,Constructive ,Domain (software engineering) ,03 medical and health sciences ,Intelligent agent ,0302 clinical medicine ,Simple (abstract algebra) ,030221 ophthalmology & optometry ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,computer ,Finite set ,Implementation - Abstract
In this paper we introduce a novel approach to discovering emergent behaviour in multiagent simulations, using evolutionary finite state machines to model intelligent agents in an adversarial two-player game. Agent behaviour is modelled as a finite set of predetermined states. The logic that leads to transitions between states is evolved to maximise fitness, which is determined through execution in a constructive simulation environment. The resultant evolved finite state machine (E-FSM) is evaluated for two finite state machine implementations, one with states specifically designed to perform a known behaviour and the other with states consisting of generic actions. Our experiments demonstrate that this approach can discover complex emergent behaviours from simple, generic actions, and use these behaviours to achieve a position of tactical superiority in the domain of air combat simulation.
- Published
- 2018
64. Submilisievert ultralow-dose CT colonography using iterative reconstruction technique: a feasibility study
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Martin Masek, Jiri Jahoda, Jiri Lisy, Lukas Lambert, Petr Ourednicek, and Jan Daneš
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Male ,medicine.medical_specialty ,Supine position ,Image quality ,Ultralow dose ,Contrast Media ,Pilot Projects ,Iterative reconstruction ,Radiation Dosage ,Triiodobenzoic Acids ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Aged ,Radiological and Ultrasound Technology ,Radon transform ,business.industry ,Distortion (optics) ,General Medicine ,Radiographic Image Enhancement ,Intestinal Diseases ,Prone position ,Feasibility Studies ,Radiographic Image Interpretation, Computer-Assisted ,Female ,Tomography ,Radiology ,business ,Colonography, Computed Tomographic - Abstract
Background Computed tomography (CT) colonography is a well established modality for the examination of symptomatic patients as well as in screening. Recent technical advances in improving image quality by iterative reconstruction contribute to the reduction of the radiation dose which is a major concern in CT imaging. Purpose To evaluate image quality of ultralow-dose submilisievert CT colonography using hybrid iterative reconstruction technique. Material and Methods Sixteen patients underwent contrast-enhanced CT colonography with standard protocol in supine position and ultralow-dose protocol in prone position. Ultralow-dose datasets were reconstructed with filtered back projection and an advanced hybrid iterative reconstruction technique. Two radiologists independently evaluated 96 colonic segments for image quality in the endoluminal view and axial thin sections. Colonic distension, smoothness of colonic wall and distortion of folds in the endoluminal view, sharpness of colonic wall delineation, perceived image noise, and presence of photon starvation artifact were rated on a five-point scale. Intraluminal noise expressed as standard deviation of Hounsfield density was measured in all segments. Results The mean radiation dose was 0.42 mSv and 5.48 mSv in prone and supine scans, respectively. All distended segments were rated evaluable in standard dose and ultralow-dose series reconstructed with the iterative reconstruction technique, whereas in 61% segments image quality was rated poor or unacceptable in ultralow-dose series where filtered back projection was used with worst ratings in the rectum and the sigmoid colon. Conclusion This pilot study shows that iterative reconstruction technique is a feasible method to decrease the radiation dose from CT colonography for both positions below 1mSv. Further investigations of larger scale need to be done to clarify, whether such a low radiation dose would influence the detection of polyps.
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- 2015
65. Thalamic Iron Differentiates Primary-Progressive and Relapsing-Remitting Multiple Sclerosis
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Martin Masek, Jan Krasensky, Petr Dusek, Dana Horakova, Manuela Vaneckova, Lukas Sobisek, C. Langkammer, P. Matras, Z. Seidl, and Andrea Burgetova
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Adult ,Male ,Pathology ,medicine.medical_specialty ,Iron ,Caudate nucleus ,Corpus callosum ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Atrophy ,Multiple Sclerosis, Relapsing-Remitting ,Thalamus ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Expanded Disability Status Scale ,business.industry ,Multiple sclerosis ,Putamen ,Adult Brain ,Quantitative susceptibility mapping ,Middle Aged ,Multiple Sclerosis, Chronic Progressive ,medicine.disease ,Magnetic Resonance Imaging ,Hyperintensity ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
BACKGROUND AND PURPOSE: Potential differences between primary progressive and relapsing remitting multiple sclerosis are the subject of ongoing controversial discussions. The aim of this work was to determine whether and how primary-progressive and relapsing-remitting multiple sclerosis subtypes differ regarding conventional MR imaging parameters, cerebral iron deposits, and their association with clinical status. MATERIALS AND METHODS: We analyzed 24 patients with primary-progressive MS, 80 with relapsing-remitting MS, and 20 healthy controls with 1.5T MR imaging for assessment of the conventional quantitative parameters: T2 lesion load, T1 lesion load, brain parenchymal fraction, and corpus callosum volume. Quantitative susceptibility mapping was performed to estimate iron concentration in the deep gray matter. RESULTS: Decreased susceptibility within the thalamus in relapsing-remitting MS compared with primary-progressive MS was the only significant MR imaging difference between these MS subtypes. In the relapsing-remitting MS subgroup, the Expanded Disability Status Scale score was positively associated with conventional parameters reflecting white matter lesions and brain atrophy and with iron in the putamen and caudate nucleus. A positive association with putaminal iron and the Expanded Disability Status Scale score was found in primary-progressive MS. CONCLUSIONS: Susceptibility in the thalamus might provide additional support for the differentiation between primary-progressive and relapsing-remitting MS. That the Expanded Disability Status Scale score was associated with conventional MR imaging parameters and iron concentrations in several deep gray matter regions in relapsing-remitting MS, while only a weak association with putaminal iron was observed in primary-progressive MS suggests different driving forces of disability in these MS subtypes.
- Published
- 2017
66. An Automatic Approach for Generation of Fuzzy Membership Functions
- Author
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Hossein Pazhoumand-Dar, Martin Masek, and Chiou Peng Lam
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Fuzzy classification ,Computer science ,Fuzzy set ,02 engineering and technology ,Type-2 fuzzy sets and systems ,computer.software_genre ,01 natural sciences ,Defuzzification ,010104 statistics & probability ,Fuzzy mathematics ,0202 electrical engineering, electronic engineering, information engineering ,Fuzzy set operations ,Fuzzy number ,020201 artificial intelligence & image processing ,Data mining ,0101 mathematics ,computer ,Membership function - Abstract
Eliciting representative membership functions is one of the fundamental steps in applications of fuzzy theory. This paper investigates an unsupervised approach that incorporates variable bandwidth mean-shift and robust statistics for generating fuzzy membership functions. The approach automatically learns the number of representative functions from the underlying data distribution. Given a specific membership function, the approach then works out the associated parameters of the specific membership function. Our evaluation of the proposed approach consists of comparisons with two other techniques in terms of (i) parameterising MFs for attributes with different distributions, and (ii) classification performance of a fuzzy rule set that was developed using the parameterised output of these techniques. This evaluation involved its application using the trapezoidal and the triangular membership functions. Results demonstrate that the generated membership functions can better separate the underlying distributions and classifiers constructed using the proposed method of generating membership function outperformed three other classifiers that used different approaches for parameterisation of the attributes.
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- 2017
67. A congenital diverticulum of the left ventricular apex manifested by stroke and recurrent ventricular tachycardia
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Martin Masek, Jaroslav Lindner, Štěpán Havránek, Aleš Linhart, Debora Karetová, Zuzana Hlubocká, Petr Kuchynka, Tomas Palecek, D. Wichterle, Jaroslava Dušková, and Gabriela Dostálová
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Heart Defects, Congenital ,medicine.medical_specialty ,Heart Ventricles ,030204 cardiovascular system & hematology ,Ventricular tachycardia ,Pathology and Forensic Medicine ,03 medical and health sciences ,0302 clinical medicine ,Congenital diverticulum ,Cardiac magnetic resonance imaging ,Predictive Value of Tests ,Recurrence ,Internal medicine ,Medicine ,Humans ,cardiovascular diseases ,030212 general & internal medicine ,Stroke ,Echocardiography, Doppler, Pulsed ,medicine.diagnostic_test ,business.industry ,Recurrent ventricular tachycardia ,General Medicine ,medicine.disease ,Fibrosis ,Magnetic Resonance Imaging ,Diverticulum ,medicine.anatomical_structure ,Treatment Outcome ,Ventricle ,cardiovascular system ,Cardiology ,Tachycardia, Ventricular ,Radiology ,Differential diagnosis ,Cardiology and Cardiovascular Medicine ,business ,Electrophysiologic Techniques, Cardiac - Abstract
Ventricular outpouchings include acquired abnormalities (aneurysms and pseudoaneurysms) and congenital ventricular diverticula (CVD). CVD represent rare cardiac pathologies. Although CVD is often associated with other cardiac and extracardiac congenital anomalies, it can also be incidentally observed in otherwise healthy subjects. CVD may lead to significant morbidity and even have lethal consequences. We describe a case of arrhythmogenic left ventricle (LV) apical CVD revealed by cardiac magnetic resonance imaging (CMRI) after being initially overlooked by echocardiography. The paper includes the review of the literature also. This clinical case highlights the possible association of this pathology with recurrent ventricular tachycardia and stroke, and illustrates the importance of multimodal imaging approach in differential diagnosis.
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- 2016
68. Mosaic tissue distribution of the tandem duplication of LAMP2 exons 4 and 5 demonstrates the limits of Danon disease cellular and molecular diagnostics
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Hana Vlaskova, Jakub Sikora, Filip Majer, Tomas Honzik, Martin Masek, Milan Elleder, Ondrej Pelak, Petr Kuchynka, Jiri Zeman, Tomáš Paleček, Tomas Kalina, and Lenka Dvorakova
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Adult ,Male ,Adolescent ,DNA Copy Number Variations ,Biology ,medicine.disease_cause ,Young Adult ,Exon ,Gene Duplication ,Lysosomal-Associated Membrane Protein 2 ,Gene duplication ,Leukocytes ,Genetics ,medicine ,Humans ,Tissue Distribution ,Danon disease ,Copy-number variation ,Gene ,Genetics (clinical) ,Mutation ,LAMP2 ,Mosaicism ,Myocardium ,Siblings ,Exons ,Flow Cytometry ,medicine.disease ,Magnetic Resonance Imaging ,Molecular biology ,Glycogen Storage Disease Type IIb ,Pedigree ,Phenotype ,Female ,Tandem exon duplication ,Granulocytes - Abstract
Alu-mediated tandem duplication of exons 4 and 5 (g.15815_22218dup6404) is a novel mutation that has been detected in the LAMP2 gene (Xq24). This exon copy number variation was found in two brothers with the typical phenotype of Danon disease, including characteristic myocardial changes on magnetic resonance imaging. The 6.4 kb duplication was identified in both boys by a combination of exon dosage qPCR analyses and duplication breakpoint/junction mapping. The rearrangement results in a plethora of abnormal LAMP2 splicing variants and also in use of likely cryptic splice sites in the 3′ terminus of LAMP2 gene. Although we found minute amounts of normal LAMP2B and LAMP2A mRNAs, no protein was detectable in peripheral blood leukocytes by flow cytometry in both brothers. Uniquely, the fraction of LAMP2-deficient granulocytes (0.06 %) assessed by flow cytometry in the patients’ asymptomatic mother substantially differed from the random distribution of X-chromosome inactivation in her leukocytes. This discrepancy was later explained by molecular genetic methods as a consequence of mosaic distribution of the mutation in her somatic tissues. Altogether, we report a novel and mosaically distributed exon copy number rearrangement in the LAMP2 gene and comment on obstacles this genetic setup presents to the overall cellular and molecular diagnostic algorithm of Danon disease. Our observations of the mosaicism in the asymptomatic mother suggest that similarly affected females could be a potentially under-diagnosed Danon disease carrier group and that LAMP2 flow cytometry, because of its supreme sensitivity, can be an efficient method for pedigree screening.
- Published
- 2013
69. E-learning with docugames:AE2 Commander
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Martin Masek and Mark P Brogan
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Engineering ,Operations research ,business.industry ,Communication ,E-learning (theory) ,Library science ,Library and Information Sciences ,First world war ,Design brief ,Enterprise information management ,Transformational leadership ,National archives ,Narrative ,business ,Associate professor - Abstract
Mark Brogan and Martin Masek teach and research in the School of Computer and Security Science at Edith Cowan University. Dr Brogan teaches and researches enterprise information management and digital recordkeeping. With Associate Professor Karen Murcia, Dr Masek coordinates research activity in ECU’s Research Centre for Transformational Games. 1 This paper describes outcomes from user acceptance testing of AE2 Commander 2 – a docugame released as alpha software in April 2011 by ECU’s Research Centre for Transformational Games. Docugames form a genre of serious games that employ digitised copy of historical sources as part of the game narrative. The design and development of AE2 Commander began in 2009, when the authors received an Ian MacLean Award 3 from the National Archives of Australia (NAA) to build an authentic role-play game based on the exploits of the World War I Australian submarine AE2. The design brief required the designers to develop a strategy for incorporating digitised copy of archival r...
- Published
- 2013
70. Early-time Observations of SN 2023wrk: A Luminous Type Ia Supernova with Significant Unburned Carbon in the Outer Ejecta
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Jialian Liu, Xiaofeng Wang, Cristina Andrade, Pierre-Alexandre Duverne, Jujia Zhang, Liping Li, Zhenyu Wang, Felipe Navarete, Andrea Reguitti, Stefan Schuldt, Yongzhi Cai, Alexei V. Filippenko, Yi Yang, Thomas G. Brink, WeiKang Zheng, Ali Esamdin, Abdusamatjan Iskandar, Chunhai Bai, Jinzhong Liu, Xin Li, Maokai Hu, Gaici Li, Wenxiong Li, Xiaoran Ma, Shengyu Yan, Jun Mo, Christophe Adami, Dalya Akl, Sarah Antier, Eric Broens, Jean-Grégoire Ducoin, Eslam Elhosseiny, Thomas M. Esposito, Michael Freeberg, Priyadarshini Gokuldass, Patrice Hello, Sergey Karpov, Isabel Márquez, Martin Mašek, Oleksandra Pyshna, Yodgor Rajabov, Denis Saint-Gelais, Marc Serrau, Oleksii Sokoliuk, Ali Takey, Manasanun Tanasan, and Damien Turpin
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Type Ia supernovae ,Astrophysics ,QB460-466 - Abstract
We present extensive photometric and spectroscopic observations of the nearby Type Ia supernova (SN) 2023wrk at a distance of about 40 Mpc. The earliest detection of this SN can be traced back to a few hours after the explosion. Within the first few days, the light curve shows a bump feature, while the B − V color is blue and remains nearly constant. The overall spectral evolution is similar to that of an SN 1991T/SN 1999aa-like SN Ia, while the C ii λ 6580 absorption line appears to be unusually strong in the first spectrum taken at t ≈ −15.4 days after the maximum light. This carbon feature disappears quickly in subsequent evolution but it reappears at around the time of peak brightness. The complex evolution of the carbon line and the possible detection of Ni iii absorption around 4700 Å and 5300 Å in the earliest spectra indicate macroscopic mixing of fuel and ash. The strong carbon lines are likely related to the collision of SN ejecta with unbound carbon, consistent with the predictions of pulsational delayed-detonation or carbon-rich circumstellar-matter interaction models. Among those carbon-rich SNe Ia with strong C ii λ 6580 absorption at very early times, the line-strength ratio of C ii to Si ii and the B − V color evolution are found to exhibit large diversity, which may be attributed to different properties of unbound carbon and outward-mixing ^56 Ni.
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- 2024
- Full Text
- View/download PDF
71. Erratum: 'Bangs and Meteors from the Quiet Comet 15P/Finlay' (2015, ApJ, 814, 79)
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Quanzhi Ye, Peter G. Brown, Charles Bell, Xing Gao, Martin Mašek, and Man-To Hui
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Astrophysics ,QB460-466 - Published
- 2024
- Full Text
- View/download PDF
72. Modeling perceived difficulty in game levels
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Chiou Peng Lam, Philip Hingston, Martin Masek, and Daniel Wheat
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Data collection ,020205 medical informatics ,business.industry ,Computer science ,Decision tree ,02 engineering and technology ,Perceptron ,Machine learning ,computer.software_genre ,Random forest ,Player experience ,C4.5 algorithm ,020204 information systems ,Multilayer perceptron ,Content generation ,0202 electrical engineering, electronic engineering, information engineering ,Artificial intelligence ,business ,computer - Abstract
The recent interest in procedural content generation for video games has created the need to establish techniques for assessment of generated content. We present an investigation into the factors determining perceived difficulty in procedurally generated game levels. In doing so, an approach to identify relevant factors pertaining to player experience is established, which is subsequently used in the development of predictive difficulty models. In this paper, we apply our methodology to the genre of 2D platformers, presenting an investigation into factors related to difficulty, the development of a test-bed that can be used to collect the data, data collection and subsequent analysis. We investigate the contribution of the identified game and player metrics towards predicting difficulty using Multi-Layer Perceptron, J48 and Random Forest classifiers from WEKA. This work is presented as a preliminary investigation into modeling difficulty from procedural content. Significantly, this investigation provides a preliminary insight into metrics that can be used for developing a classification model for perceived difficulty.
- Published
- 2016
73. Using Isovists to Evolve Terrains with Gameplay Elements
- Author
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Philip Hingston, Andrew Pech, Chiou Peng Lam, and Martin Masek
- Subjects
Computer science ,Isovist ,05 social sciences ,ComputingMilieux_PERSONALCOMPUTING ,050801 communication & media studies ,020207 software engineering ,Terrain ,02 engineering and technology ,Field (computer science) ,Computer game ,Set (abstract data type) ,0508 media and communications ,Human–computer interaction ,Computer graphics (images) ,Genetic algorithm ,0202 electrical engineering, electronic engineering, information engineering ,Representation (mathematics) ,Video game - Abstract
The virtual terrain for a video game generally needs to exhibit a collection of gameplay elements, such as some areas suitable for hiding and others for large scale battles. A key problem in automating terrain design is the lack of a quantitative definition of terrain gameplay elements. In this paper, we address the problem by proposing a representation for gameplay elements based on a combination of space-based isovist measures from the field of architecture and graph-connectivity metrics. We then propose a genetic algorithm-based approach that evolves a set of modifications to an existing terrain so as to exhibit the gameplay element characteristics. The potential for this approach in the design of computer game environments is examined by generating terrain containing instances of the “hidden area” game element type. Results from four preliminary tests are described to show the potential of this research.
- Published
- 2016
74. WAMbot: Team MAGICian's entry to the Multi Autonomous Ground-robotic International Challenge 2010
- Author
-
Sam Lopes, Thomas Bräunl, Kevin Vinsen, Adam Gandossi, Robert G. Reid, Chang Su Lee, Sushil Pangeni, Adrian Boeing, Mark Boulton, Brian Frisch, Anthony Attwood, Frank Ophelders, Michael Fazio, Aidan Morgan, Martin Masek, and Nicolas Garel
- Subjects
Operations research ,Unmanned ground vehicle ,Control and Systems Engineering ,Human–computer interaction ,Computer science ,Systems architecture ,Multi Autonomous Ground-robotic International Challenge ,User interface ,Computer Science Applications - Abstract
This article describes “WAMbot,'' an autonomous unmanned ground vehicle and the Team MAGICian solution to the 2010 Multi Autonomous Ground-robotic International Challenge (MAGIC). The system architecture, hardware, sensing, planning, navigation, mapping systems, and user interface were specifically designed to address the demands of the large-scale distributed reconnaissance and surveillance task presented in the challenge. The resulting system was selected as a finalist and ultimately placed 4th in MAGIC 2010. © 2012 Wiley Periodicals, Inc. © 2012 Wiley Periodicals, Inc.
- Published
- 2012
75. A Novel Fuzzy Based Home Occupant Monitoring System Using Kinect Cameras
- Author
-
Chiou Peng Lam, Hossein Pazhoumand-Dar, and Martin Masek
- Subjects
Training set ,Association rule learning ,Orientation (computer vision) ,business.industry ,Computer science ,Feature extraction ,Fuzzy set ,Monitoring system ,Fuzzy logic ,Computer vision ,Artificial intelligence ,Duration (project management) ,Set (psychology) ,business - Abstract
In this paper, an approach is presented for the detection of abnormal behaviours in the activities of people living alone in their homes. The proposed approach takes input from Kinect cameras and extracts a number of visual attributes that represent the occupant's location and orientation. A set of fuzzy logic parameters is first learnt from the training data. Next the proposed approach learns epochs of activities in each location and then generates models of normal behaviour patterns. Unusual behaviour is then detected in subsequent data by looking for patterns which differ from the learnt normal behaviours based on their time of occurrence, visual attributes, or duration. Experiments conducted showed the effectiveness of the proposed system.
- Published
- 2015
76. Large metastatic involvement of pericardium, myocardium and andocardium of both heart ventricles in pulmonary adenocarcinoma
- Author
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Dalibor Kašík, Anna Korcová, Dana Matoušková, Martin Masek, Tomáš Paleček, and Pavel Franc
- Subjects
Pathology ,medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,Pulmonary adenocarcinoma ,Medicine ,Pericardium ,Cardiology and Cardiovascular Medicine ,business - Abstract
Kasuistika dokumentuje klinický průběh, výsledky zobrazovacich vysetřeni a pitevni nalez nemocneho s metastatickým postiženim vsech srdecnich struktur jako prvni manifestaci plicniho adenokarcinomu.
- Published
- 2011
77. Cardiac involvement in lymphoma mimicking hypertrophic cardiomyopathy
- Author
-
Martin Masek, Lukas Lambert, Valerie Knotkova, Tomas Palecek, and Petr Kuchynka
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,business.industry ,Lymphoma, Non-Hodgkin ,Myocardium ,05 social sciences ,Cardiomyopathy ,Hypertrophic cardiomyopathy ,Cardiomyopathy, Hypertrophic ,030204 cardiovascular system & hematology ,medicine.disease ,Lymphoma ,Diagnosis, Differential ,03 medical and health sciences ,0302 clinical medicine ,Leukemic Infiltration ,0502 economics and business ,medicine ,Humans ,050211 marketing ,Cardiac Surgical Procedures ,Cardiology and Cardiovascular Medicine ,business - Published
- 2018
78. Multimodality imaging in endomyocardial fibrosis associated with Hodgkin lymphoma
- Author
-
Lukas Lambert, Václav Ptáčník, Tomas Palecek, Petr Kuchynka, and Martin Masek
- Subjects
Male ,medicine.medical_specialty ,Endomyocardial fibrosis ,Treatment outcome ,MEDLINE ,Multimodal Imaging ,Risk Assessment ,Medical imaging ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Heart Failure ,business.industry ,Follow up studies ,General Medicine ,Middle Aged ,Endomyocardial Fibrosis ,Hodgkin Disease ,Treatment Outcome ,Echocardiography ,Positron-Emission Tomography ,Hodgkin lymphoma ,Lymph Nodes ,Radiology ,Cardiology and Cardiovascular Medicine ,Risk assessment ,business ,Follow-Up Studies - Published
- 2018
79. Computed Tomographic Angiography in Proximal Femoral Focal Deficiency
- Author
-
Pavel Dungl, Monika Frydrychová, Martin Masek, Jiří Chomiak, and Martin Horák
- Subjects
Male ,medicine.medical_specialty ,Adolescent ,Femoral artery ,Young Adult ,medicine.artery ,Inferior gluteal artery ,Deep Femoral Artery ,medicine ,Humans ,Orthopedics and Sports Medicine ,Femur ,Child ,medicine.diagnostic_test ,business.industry ,Angiography ,Infant ,External iliac artery ,General Medicine ,Anatomy ,medicine.disease ,Internal iliac artery ,Popliteal artery ,Musculoskeletal Abnormalities ,Femoral Artery ,Lower Extremity ,Child, Preschool ,Proximal femoral focal deficiency ,Female ,Surgery ,Radiology ,Tomography, X-Ray Computed ,business - Abstract
Background Because there is limited information concerning the vascular pattern and the role of vessels in patients with proximal femoral focal deficiency, the vascular supply of the lower extremities was studied systematically with use of computed tomographic angiography in order to identify vascular changes, relate any vascular changes to the classification of the deficiency, and establish that there are no major changes in the topographical anatomy of the vessels. Methods Standardized computed tomographic techniques were used in twenty-one patients (thirteen boys and eight girls who ranged from one to nineteen years old) with proximal femoral focal deficiency types I through IV and VII, VIII, and IX, according to the Pappas classification. Results A common anatomical vascular pattern, in which the hypoplastic extremity was supplied through the femoral artery, was detected in nineteen patients. In patients with Pappas type-I through IV disease, the external iliac, femoral, and deep femoral arteries were substantially reduced in length and diameter and the deep femoral artery arose more proximally in comparison with that in the contralateral extremity; however, in the patients with Pappas type-VII, VIII, or IX disease, the diameters of the arteries and the origin of the deep femoral artery were similar to those of the contralateral extremity. In two patients with Pappas type-III disease, atypical anatomy of the vessels was found. The anterior part of the thigh and the pseudarthrosis were supplied through the femoral artery (the external iliac artery) as a terminal branch, while the remainder of the extremity was supplied from the internal iliac artery, which entered the thigh posterior to the hip as the inferior gluteal artery and continued as the artery to the sciatic nerve to the popliteal artery. No substantial anastomoses were found between the femoral and the posterior arteries in these vascular patterns. Conclusions Computed tomographic-angiographic reconstruction can be used to depict the spatial configuration of the pseudarthrosis and the vascular pattern of the extremity in patients with proximal femoral focal deficiency. We found distinct vascular changes in the majority of the involved thighs, but there were no typical changes related to the Pappas classification. Because we found atypical vascular patterns in two patients, evaluation of the vessels with use of various diagnostic methods is recommended in patients with severe types of proximal femoral focal deficiency.
- Published
- 2009
80. Imaging findings after methanol intoxication (cohort of 46 patients)
- Author
-
Manuela, Vaneckova, Sergey, Zakharov, Jiri, Klempir, Evzen, Ruzicka, Ondrej, Bezdicek, Hana, Brozova, Pavel, Diblik, Michal, Miovsky, Jaroslav Alois, Hubacek, Pavel, Urban, Petr, Ridzon, Daniela, Pelclova, Andrea, Burgetova, Martin, Masek, Katerina, Kotikova, Kamila, Peterova, Irena, Liskova, Lidmila, Hamplova, and Zdenek, Seidl
- Subjects
Adult ,Male ,Putaminal Hemorrhage ,Methanol ,Poisoning ,Putamen ,Brain ,Middle Aged ,Globus Pallidus ,Magnetic Resonance Imaging ,White Matter ,Cohort Studies ,Solvents ,Humans ,Female ,Tomography, X-Ray Computed ,Aged ,Brain Stem - Abstract
Our goal is to demonstrate the variability of imaging findings, primarily in the MRI, in 46 patients who survived acute methanol poisoning. This cohort of patients is the largest such sample group examined by MRI.Patients were examined by means of imaging methods (42 patients by MRI and 4 by CT). All had an identical protocol of MR examination (T2WI, FLAIR, T1WI with or without application of contrast medium and T2WI/FFE, DWI in the transversal plane of the scan, and with focus on the optic nerves in the coronal plane of the scan in T2WI-SPIR).Imaging methods revealed a positive finding associated with methanol intoxication in 21 patients (46%). These consisted of symmetrical lesions in the putamen--13 patients (28%), haemorrhage--13 cases (28%), deposits in white matter with localization primarily subcortically--4 cases (9%), lesions in the region of the globus pallidus--7 cases (15%) (in 6 cases without combination with the lesions in the putamen), lesions in the brainstem afflicted 6 patients (13%), and lesion in the cerebellum was found in one case. A pathological finding was found only in the patients examined by MRI.Almost half of the patients who survived acute methanol poisoning had pathological findings by MRI. The most common finding concerned an affliction of the putamen, which is a predilection area. An interesting finding was the relatively frequent occurrence of selective lesion of the globus pallidus, which is more usually associated with other types of intoxication.
- Published
- 2015
81. Dynamic Difficulty Adjustment in 2D Platformers through Agent-Based Procedural Level Generation
- Author
-
Martin Masek, Chiou Peng Lam, Daniel Wheat, and Philip Hingston
- Subjects
Game mechanics ,Multimedia ,Computer science ,ComputingMilieux_PERSONALCOMPUTING ,Entertainment industry ,Context (language use) ,Interactive evolutionary computation ,computer.software_genre ,computer ,Evolutionary computation ,Diversity (business) - Abstract
The rapid growth of the entertainment industry has driven the requirement for more efficient development of computerized games. Importantly, the diversity of audiences that participate in playing games has called for the development of new technologies that allow games to address users with differing levels of skills and preferences. This study explored the application of dynamic difficulty adjustment in computerized 2D plat former games through procedural level generation and interactive evolutionary computation. Computerized agents were introduced into the evolutionary cycle to play game levels in the player's stead. Additionally, agent behavior was based on the player's game-play characteristics, which has provided a more practical means for evaluating and evolving game levels tailored to a particular player's skills.
- Published
- 2015
82. Evolving Cellular Automata for Maze Generation
- Author
-
Philip Hingston, Chiou Peng Lam, Andrew Pech, and Martin Masek
- Subjects
Set (abstract data type) ,business.industry ,Computer science ,ComputingMilieux_PERSONALCOMPUTING ,Hardware_INTEGRATEDCIRCUITS ,Evolutionary algorithm ,Procedural generation ,Artificial intelligence ,business ,Cellular automaton ,Mobile automaton - Abstract
This paper introduces a new approach to the procedural generation of maze-like game level layouts by evolving CA. The approach uses a GA to evolve CA rules which, when applied to a maze configuration, produce level layouts with desired maze-like properties. The advantages of this technique is that once a CA rule set has been evolved, it can quickly generate varying instances of maze-like level layouts with similar properties in real time.
- Published
- 2015
83. The Role of Magnetic Resonance Imaging and Cardiac Computed Tomography in the Assessment of Left Atrial Anatomy, Size, and Function
- Author
-
Martin Masek, Barbara A. Danek, Lukas Lambert, Jana Podzimkova, Petr Kuchynka, Tomas Palecek, and Vladimir Cerny
- Subjects
medicine.medical_specialty ,Cardiac computed tomography ,medicine.medical_treatment ,lcsh:Medicine ,Catheter ablation ,Review Article ,General Biochemistry, Genetics and Molecular Biology ,Left atrial ,Internal medicine ,Atrial Fibrillation ,medicine ,Humans ,cardiovascular diseases ,Heart Atria ,General Immunology and Microbiology ,medicine.diagnostic_test ,business.industry ,lcsh:R ,Magnetic resonance imaging ,Atrial fibrillation ,General Medicine ,medicine.disease ,Ablation ,Magnetic Resonance Imaging ,Review article ,Cardiology ,cardiovascular system ,Catheter Ablation ,Atrial Function, Left ,Tomography ,Radiology ,business ,Tomography, X-Ray Computed - Abstract
In the last decade, there has been increasing evidence that comprehensive evaluation of the left atrium is of utmost importance. Numerous studies have clearly demonstrated the prognostic value of left atrial volume for long-term outcome. Furthermore, advances in catheter ablation procedures used for the treatment of drug-refractory atrial fibrillation require the need for detailed knowledge of left atrial and pulmonary venous morphology as well of atrial wall characteristics. This review article discusses the role of cardiac magnetic resonance and computed tomography in assessment of left atrial size, its normal and abnormal morphology, and function. Special interest is paid to the utility of these rapidly involving noninvasive imaging methods before and after atrial fibrillation ablation.
- Published
- 2014
84. The diagnostic performance of cardiac magnetic resonance in detection of myocardial involvement in AL amyloidosis
- Author
-
Romana Rysava, Michal Fikrle, Ivan Spicka, Petr Kuchynka, Jan Straub, Tomáš Paleček, Martin Masek, and Aleš Linhart
- Subjects
Male ,medicine.medical_specialty ,Physiology ,Population ,Cardiomyopathy ,Magnetic Resonance Imaging, Cine ,030204 cardiovascular system & hematology ,Sensitivity and Specificity ,03 medical and health sciences ,Ventricular Dysfunction, Left ,0302 clinical medicine ,Physiology (medical) ,Internal medicine ,AL amyloidosis ,medicine ,Late gadolinium enhancement ,Humans ,cardiovascular diseases ,030212 general & internal medicine ,education ,Aged ,education.field_of_study ,Ejection fraction ,business.industry ,Reproducibility of Results ,General Medicine ,Amyloidosis ,medicine.disease ,Amyloid heart disease ,Echocardiography ,cardiovascular system ,Cardiology ,Female ,Amyloid cardiomyopathy ,Cardiac magnetic resonance ,business ,Cardiomyopathies - Abstract
Summary Background The non-invasive assessment of amyloid heart disease may be challenging. Cardiac magnetic resonance (CMR) represents a method of choice for assessment of left ventricular (LV) morphology and function, and it also provides a unique possibility to evaluate the presence of amyloid deposition by the late gadolinium enhancement (LGE) technique. However, so far, published studies have not been consistent in terms of described LGE patterns associated with amyloid cardiomyopathy. Aims To compare echocardiographic and CMR assessment of LV morphology and function and to evaluate the presence and pattern of LGE in a population of patients with AL amyloid cardiomyopathy. Methods Twenty-two consecutive patients with newly diagnosed AL amyloid cardiomyopathy and without contraindications to CMR were comprehensively examined by echocardiography and CMR. Results Echocardiography and CMR did not differ in the evaluation of interventricular septal thickness, LV end-diastolic diameter and ejection fraction. Significant differences were found between echocardiographic and CMR estimates of LV end-diastolic volume (P
- Published
- 2014
85. Connectivity check for modular self reconfigurable robots
- Author
-
Rajesh Subramanian, Martin Masek, and Chang Su Lee
- Subjects
Set (abstract data type) ,Distributed algorithm ,business.industry ,Search algorithm ,Computer science ,Distributed computing ,Control (management) ,Robot ,Modular design ,business ,Key issues - Abstract
A problem in configuring modular self-reconfigurable robots with distributed control is determining whether a module can be moved without breaking the system apart. In finding a set of modules that can be safely moved, the key issues are to maximize the number of mobile modules identified and minimize the time consumed in finding these modules. In this study, a distributed search algorithm is proposed and compared to an existing approach.
- Published
- 2013
86. Activities of daily living classification using depth features
- Author
-
Laurence Da Luz, Martin Masek, and Chiou Peng Lam
- Subjects
Activities of daily living ,Multimedia ,Remote patient monitoring ,Computer science ,health care facilities, manpower, and services ,health services administration ,Observational study ,social sciences ,computer.software_genre ,computer ,humanities ,Assisted living - Abstract
The increasing elderly population presents a challenge on the resources of carers and assisted living communities. In this paper, we present an algorithm based around the Microsoft Kinect for monitoring activities of daily living. The system analyses the behaviour of occupants to provide carers with valuable observational data, and has the capacity to detect abnormal events in the home.
- Published
- 2013
87. WAMbot: Simulation and modelling of a team of autonomous mobile robots
- Author
-
Thomas Bräunl, Adrian Boeing, Sushil Pangeni, Frank Ophelders, and Martin Masek
- Subjects
Engineering ,business.industry ,Game engine ,Magic (programming) ,Mobile robot ,Robotics ,Construct (python library) ,Task (project management) ,Domain (software engineering) ,Embedded system ,Autonomous ground vehicle ,Artificial intelligence ,business ,Software engineering - Abstract
Simulation is an essential early evaluation tool for mobile robot research and development, and different stages of development have individual simulator needs. In this paper, we document details of two simulation tools that were developed for an entry into the MAGIC 2010 challenge, an autonomous ground vehicle competition. In developing the entry, simulators were used in two domains: problem analysis and solution testing. The problem analysis simulator was built using a commercial 3D game engine, whilst the simulator aimed at testing of the solution was built using a standard robotics library. By leveraging existing technologies appropriate for each domain, the task of simulator construction was simplified. The split allowed problem exploration independent of selected hardware, allowing for early simulation. These simulators allowed a team composed mostly of part-time volunteers to construct a complex distributed, multi-robot system and proved essential to our team's success in the MAGIC 2010 challenge.
- Published
- 2013
88. Exploration games played on a DDR pad can constitute beneficial physical exercise
- Author
-
Martin Masek, Kim Thy Nguyen, Yuwanuch Gulatee, and Bohan Li
- Subjects
education.field_of_study ,Game mechanics ,Game design ,Multimedia ,Computer science ,Population ,ComputingMilieux_PERSONALCOMPUTING ,Physical exercise ,Set (psychology) ,education ,computer.software_genre ,Metaverse ,computer - Abstract
The addition of an exercise component to computer games is a method that attempts to increase exercise compliance among the population. Various attempts at such games have been made, both commercially and as research projects, but the set of studied game mechanics that are both entertaining and provide beneficial exercise are relatively small. In our work, a game mechanic was designed for a floor-based input controller (DDR Pad). Rather than the standard mechanic usually employed for this device, our approach allows the player to explore a virtual world, requiring exertive movements on the input device in order to progress. The exercise is motivated implicitly through the game goals and a mechanism exists to control the pace of the game by monitoring the player's heart rate. In our trials, we have found that the game is engaging for the participants. The game also provides a beneficial level of exercise, with the player's heart rate, on average, rising to a level that constitutes moderate exercise after three minutes and forty seconds, and increasing from thereon.
- Published
- 2012
89. Evaluating coevolution on a multimodal problem
- Author
-
Philip Hingston, Tirtha R. Ranjeet, Martin Masek, and Chiou Peng Lam
- Subjects
Computer science ,business.industry ,Evolutionary algorithm ,TheoryofComputation_GENERAL ,Artificial intelligence ,Machine learning ,computer.software_genre ,business ,computer ,Coevolution - Abstract
Coevolutionary algorithms are a special kind of evolutionary algorithm with advantages in solving certain specific kinds of problems. In particular, competitive coevolutionary algorithms can be used to study problems in which two sides compete against each other and must choose a suitable strategy. Often these problems are multimodal --- there is more than one strong strategy for each side. In this paper, we introduce a scalable multimodal test problem for competitive coevolution, and use it to investigate the effectiveness of some common coevolutionary algorithm enhancement techniques in improving a coevolutionary algorithm's ability to explore landscapes with multiple optima.
- Published
- 2012
90. Using Monte Carlo Tree Search for replanning in a multistage simultaneous game
- Author
-
Philip Hingston, Daniel Beard, and Martin Masek
- Subjects
symbols.namesake ,Tree traversal ,Mathematical optimization ,Nash equilibrium ,Computer science ,Monte Carlo method ,Monte Carlo tree search ,symbols ,Approximation algorithm ,Simultaneous game ,Game theory - Abstract
In this study, we introduce MC-TSAR, a Monte Carlo Tree Search algorithm for strategy selection in simultaneous multistage games. We evaluate the algorithm using a battle planning scenario in which replanning is possible. We show that the algorithm can be used to select a strategy that approximates a Nash equilibrium strategy, taking into account the possibility of switching strategies part way through the execution of the scenario in the light of new information on the progress of the battle.
- Published
- 2012
91. A Multimodal Problem for Competitive Coevolution
- Author
-
Martin Masek, Tirtha R. Ranjeet, Chiou Peng Lam, and Philip Hingston
- Subjects
business.industry ,Computer science ,Scalability ,Evolutionary algorithm ,TheoryofComputation_GENERAL ,Artificial intelligence ,Machine learning ,computer.software_genre ,business ,computer ,Competitive coevolution ,Coevolution - Abstract
Coevolutionary algorithms are a special kind of evolutionary algorithm with advantages in solving certain specific kinds of problems. In particular, competitive coevolutionary algorithms can be used to study problems in which two sides compete against each other and must choose a suitable strategy. Often these problems are multimodal -- there is more than one strong strategy for each side. In this paper, we introduce a scalable multimodal test problem for competitive coevolution, and use it to investigate the effectiveness of some common coevolutionary algorithm enhancement techniques.
- Published
- 2012
92. The Effects of Diversity Maintenance on Coevolution for an Intransitive Numbers Problem
- Author
-
Martin Masek, Chiou Peng Lam, Tirtha R. Ranjeet, and Philip Hingston
- Subjects
Mathematical optimization ,Diversity maintenance ,Relation (database) ,Computer science ,business.industry ,media_common.quotation_subject ,Measure (mathematics) ,Convergence (routing) ,Quality (business) ,Population diversity ,Artificial intelligence ,business ,Coevolution ,media_common ,Fitness sharing - Abstract
In this paper, we investigate the effectiveness of several techniques commonly recommended for overcoming convergence problems with coevolutionary algorithms. In particular, we investigate effects of the Hall of Fame, and of several diversity maintenance methods, on a problem designed to test the ability of coevolutionary algorithms to deal with an intransitive superiority relation between solutions. We measure and analyse the effects of these methods on population diversity and on solution quality.
- Published
- 2011
93. Critical Infrastructure Protection Risk Modelling with Games Technology
- Author
-
William J Bailey, Adrian Boeing, and Martin Masek
- Subjects
Engineering ,Security analysis ,Real-time simulation ,business.industry ,Game engine ,Critical infrastructure protection ,Lower cost ,Computer security ,computer.software_genre ,Risk assessment ,business ,computer ,Critical infrastructure - Abstract
Threats to critical infrastructure are not passive. Trying to identify what is in fact ’critical’ is proving to be very difficult as threats constantly evolve. A major benefit of simulating the infrastructure is that security tests and risk modelling can be applied before infrastructure is built or its environment modified, allowing for lower cost design alterations to minimise vulnerabilities. By using the 3D environment of an existing Game Engine we can explore several possibilities for security analysis that existing tools, due to their global view of the problem, do not allow. Providing participants with a first-person view of the situation allows for more realistic role-play, whilst the networked gaming technology allows remote experts to interact in an intuitive environment and explore, identify and assess the critical components of the infrastructure.
- Published
- 2010
94. Exergame development using the dual flow model
- Author
-
Jeff Sinclair, Martin Masek, and Philip Hingston
- Subjects
Game testing ,Multimedia ,Human–computer interaction ,Computer science ,Pilot trial ,ComputingMilieux_PERSONALCOMPUTING ,DUAL (cognitive architecture) ,computer.software_genre ,Data flow model ,Video game ,computer - Abstract
Exergaming, the merger of exercise and video games, tries to use the engaging experience of playing a video game to help people achieve their exercise requirements. To guide the design of such games the dual flow model, an extension of the theory of flow to both mental and physical experience, has been proposed. This paper presents the development of an exergame system designed to demonstrate the validity of the dual flow model, along with initial results from a pilot trial. The results show that such a game system can be used to deliver the required exercise across a range of participants.
- Published
- 2009
95. Remote home-based ante and post natal care
- Author
-
Chang Su Lee, Angela Fyneman, Martin Masek, Keng T. Tan, and Chiou Peng Lam
- Subjects
education.field_of_study ,business.industry ,Population ,Mobile computing ,Computer security ,computer.software_genre ,Intervention (law) ,Mobile phone ,Server ,Health care ,Medicine ,Mobile technology ,business ,Location ,education ,computer - Abstract
Australia is geographically large and sparsely populated. Thus, its population is subject to inequalities in healthcare based on geographic location. This is particularly true for the management of pregnancies at risk, which require regular monitoring. We discuss a solution in the form of a framework based on inexpensive monitoring devices coupled with a mobile phone and PC systems to enable enhanced monitoring capabilities and remote connectivity. The system has the potential to reduce unnecessary travel for regular checkups. Importantly, this system allows monitoring and diagnosis, as well as support for the mother, to be available remotely at any time allowing problems to be detected earlier so that appropriate intervention can be given if needed.
- Published
- 2009
96. Towards higher accuracy and better noise-tolerance for fetal heart rate monitoring using Doppler ultrasound
- Author
-
Chang Su Lee, Martin Masek, Keng T. Tan, and Chiou Peng Lam
- Subjects
medicine.diagnostic_test ,Computer science ,Fetal heart rate monitoring ,Fetal heart ,Ultrasonic imaging ,Fetal ecg ,symbols.namesake ,Noise ,Ultrasound probe ,Noise tolerance ,Heart rate ,Heart beat ,symbols ,Electronic engineering ,medicine ,Doppler ultrasound ,Doppler effect ,Electrocardiography ,Biomedical engineering - Abstract
Doppler ultrasound monitors are commonly used to measure the Fetal Heart Rate (FHR) in routine screenings. They are less intrusive than Fetal Electrocardiography (FECG), but are more prone to noise and thus seen as less accurate devices. Recent developments resulted in beat-to-beat heart rate algorithms for Doppler shift monitors that claimed to approach the accuracy of that obtained from direct FECG. We evaluate one such algorithm, along with a noise tolerant improvement using a mixture of synthetic and real fetal heart data in order to quantify their accuracy and robustness in the presence of the typical noise in signals from an ultrasound probe. The findings showed that our proposed approach achieved higher accuracy and better robustness compared to the beat-to-beat fetal heart detection approach.
- Published
- 2009
97. Advances in fetal heart rate monitoring using smart phones
- Author
-
Keng T. Tan, Chiou Peng Lam, Chang Su Lee, and Martin Masek
- Subjects
education.field_of_study ,Telemedicine ,business.industry ,Remote patient monitoring ,Computer science ,Fetal heart rate monitoring ,Population ,GSM ,Embedded system ,Mobile telephony ,General Packet Radio Service ,business ,education ,Computer network - Abstract
It has been shown that the rate of preterm birth in remote and rural populations in Australia is more than twice of those in the metropolitan population, and that increased access to quality antenatal care in such communities leads to a significant improvement. This paper describes a system that supports remote fetal heart rate monitoring, thus providing a technique that addresses this need for better remote antenatal care. The application involves a smart phone, a portable Doppler ultrasound device, a remote back-end server and network connectivity provided by the Global System for Mobile communications (GSM) and General Packet Radio Service (GPRS) networks. Algorithms for fetal heart rate detection were adapted to cater for the lower processing powers on the smart phone. The accuracy of this detection algorithm in the mobile application was evaluated and found to be highly comparable to that of a MATLAB implementation on a PC.
- Published
- 2009
98. Raising Heart Rate with Dance Pad Based Computer Games
- Author
-
Liam Collins, Martin Masek, Philip Hingston, Kazunori Nosaka, and Matthew Carrigy
- Subjects
Game design ,Multimedia ,Dance ,Heart rate ,computer.software_genre ,Psychology ,computer ,Raising (linguistics) - Published
- 2009
99. Secondary-progressive form of multiple sclerosis: MRI changes versus clinical status
- Author
-
Martin, Masek, Manuela, Vaneckova, Jan, Krasensky, Jan, Danes, Eva, Havrdova, Tereza, Hrebikova, and Zdenek, Seidl
- Subjects
Adult ,Male ,Disability Evaluation ,Multiple Sclerosis, Relapsing-Remitting ,Statistics as Topic ,Disease Progression ,Brain ,Humans ,Female ,Atrophy ,Middle Aged ,Multiple Sclerosis, Chronic Progressive ,Magnetic Resonance Imaging - Abstract
To monitor the interaction between the clinical manifestation of the secondary progressive form of multiple sclerosis (SPMS) expressed in the Expanded Disability Status Scale (EDSS) and abnormal findings in magnetic resonance imaging (MRI) of the brain. To compare a time line of brain atrophy in patients with SPMS, patients with relapsing-remitting multiple sclerosis (RRMS) and the healthy population.Brain atrophy, volume of increased signal lesions on Fluid Attenuated Inversion Recovery Sequence (FLAIR) sequence (s.c.lesion load) and decreased signal lesions on T1 weighted sequence (s.c. black holes) were measured semi-automatically and correlated with EDSS in 12 patients. Further, we compared a time line of brain parenchyma fraction (BPF) loss in patients with SPMS, patients with RRMS and the healthy population.In patients with SPMS, no statistical correlation was found between lesion load in FLAIR and EDSS and there was also no significant statistical correlation (p=0.1134) between the volume of "black holes" and EDSS. However, we did confirm a significant correlation between increase in brain atrophy and clinical status (p=0.0093). Comparison of patients with SPMS or RRMS and the healthy population revealed that brain atrophy progressed most rapidly in patients with SPMS.The presence of a statistically significant difference in BPF loss between patients with SPMS or RRMS and the healthy population merits further study despite the small size of our sample. We postulate that the measurement of brain atrophy could be helpful in determining the transition of RRMS to SPMS and thereby predict the progression of the disease in the future.
- Published
- 2008
100. Patients' stratification and correlation of brain magnetic resonance imaging parameters with disability progression in multiple sclerosis
- Author
-
Ondrej Dolezal, Andrea Burgetova, Martin Masek, Eva Havrdova, Jan Krasensky, Dana Horakova, Manuela Vaneckova, and Zdenek Seidl
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Adolescent ,Severity of Illness Index ,Lesion load ,Correlation ,Young Adult ,Atrophy ,Multiple Sclerosis, Relapsing-Remitting ,medicine ,Humans ,Disability progression ,Brain magnetic resonance imaging ,In patient ,skin and connective tissue diseases ,medicine.diagnostic_test ,business.industry ,Multiple sclerosis ,Brain ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Neurology ,Disease Progression ,Female ,sense organs ,Neurology (clinical) ,Radiology ,business ,Follow-Up Studies - Abstract
Aims: The objective was to correlate the change in the lesion load (LL) and brain atrophy in patients with multiple sclerosis (MS) with progression of clinical disability, represented by the Expanded Disability Status Scale (EDSS), and to test if stratification of patients according to magnetic resonance imaging (MRI) criteria can increase the predictive ability of MRI for MS clinical development. Methods: 181 patients with clinically definite relapsing-remitting MS underwent MRI for a period of up to 5 years. Grouping of patients according to the LL value at the study entry revealed a substantial increase in the Spearman rank correlation coefficient R. Results: For the low LL cohort of patients, we found a statistically significant correlation (R up to –0.71 with p < 0.01) of a later increase in the EDSS score (years 4 and 5) with increased brain atrophy in the first 2 years. For the high LL group, we found a statistically significant correlation (R up to 0.72 with p < 0.01) of a later increase in the EDSS score (years 4 and 5) with an increase in the LL value in the first year. Conclusions: We conclude that stratification of patients according to the MRI criterion (LL) can increase the predictive ability of MRI.
- Published
- 2008
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