Author

Tahir Ahmad

Universiti Teknologi Malaysia, Malaysia

10 articles in our journals

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Research ArticleOpen accessSpatial Interaction Image of Electroencephalography Signal during Epileptic Seizure on Flat ElectroencephalographyGoh Chien Yong, Tahir Ahmad, Normah MaanElectroencephalogram (EEG) is widely used for recording the brain electrical activity. It plays an important role in the detection and classification of epilepsy seizures. In addition, it is believed to possess the ability to detect the location of epileptic focus to some degree. In this study, an EEG data during seizure obtained is analysed and transformed into an image form, … …Journal of Mathematics and Statistics, Vol. 13, Issue 1 · 13 Mar 2017 · 6,901 accessesView PDF Cite

Research ArticleOpen accessCoordinated Transformation for Fuzzy Autocatalytic Set of Fuzzy Graph Type-3Tahir Ahmad, Sumarni Abu Bakar, Sabariah Baharun, Faisal A.M. BinjadhnanFuzzy Autocatalytic Set (FACS) of fuzzy graph Type-3 was established in the effort to describe the underlying phenomena of a clinical waste incineration process. Further research could be explored to scrutinize this concept especially in looking at its mathematical structure. In this paper, we highlighted the mathematical structures of FACS particularly on the algebraic structures of its matrix and graph. … …Journal of Mathematics and Statistics, Vol. 11, Issue 4 · 31 Jan 2016 · 7,150 accessesView PDF Cite

Research ArticleOpen accessGraph Representation for Secondary System of Pressurized Water Reactor with Autocatalytic Set ApproachAzmirul Ashaari, Tahir Ahmad, Mustaffa Shamsuddin et al.The pace of nuclear reactor development in increasing and this is caused by the high authoritative ordinance of electricity from the end users. Furthermore, maintaining and controlling nuclear reactor operation are high priorities due to safety reasons. The aim of this paper is to describe the secondary system of Pressurized Water Reactor (PWR) system by using graph. Furthermore, fuzzy graph … …Journal of Mathematics and Statistics, Vol. 11, Issue 4 · 30 Dec 2015 · 7,066 accessesView PDF Cite

Research ArticleOpen accessSEGMENTATION OF ELECTROENCEPHALOGRAM SIGNALS DURING EPILEPTIC SEIZURES BY USING FUZZY C-MEANSMuhammad Abdy, Tahir AhmadElectroencephalogram (EEG) is a recording of electrical activity of the brain. It contains valuable information related to the different physiological states of the brain. A quantitative EEG analysis has been developed over the years that introduce objective measure, reflecting not only the characteristics of the brain activity itself but also giving clues concerning the underlying associated neural dynamics. In this … …American Journal of Applied Sciences, Vol. 11, Issue 10 · 11 Nov 2014 · 6,234 accessesView PDF Cite

Research ArticleOpen accessFUZZY TOPOLOGICAL DIGITAL SPACE OF FLAT ELECTROENCEPHALOGRAPHY DURING EPILEPTIC SEIZURESMuhammad Abdy, Tahir AhmadEpileptic seizures are manifestations of epilepsy caused a temporary electrical disturbance in a group of brain cells. Electroencephalography (EEG) is a recording of electrical activity of the brain and it contains valuable information related to the different physiological states of the brain. Flat EEG (fEEG) was developed to compress and analyze information in the brain during epileptic seizures obtained from … …Journal of Mathematics and Statistics, Vol. 9, Issue 3 · 5 Jul 2013 · 7,205 accessesView PDF Cite

Research ArticleOpen accessGRAPH OF FINITE SEQUENCE OF FUZZY TOPOGRAPHIC TOPOLOGICAL MAPPING OF ORDER TWOMohamed Sayed, Tahir AhmadFuzzy Topographic Topological Mapping (FTTM) was built to solve the neuromagnetic inverse problem to determine the location of epileptic foci in epilepsy disorder patient. The model which consists of topological and fuzzy structures is composed into three mathematical algorithms. FTTM consists of four topological spaces and connected by three homeomorphisms. FTTM version 1 is also homeomorphic to FTTM version 2. … …Journal of Mathematics and Statistics, Vol. 9, Issue 1 · 15 Mar 2013 · 7,461 accessesView PDF Cite

Research ArticleOpen accessFlows of Continuous-Time Dynamical Systems with No Periodic Orbit as an Equivalence Class under Topological Conjugacy RelationTahir Ahmad, Tan Lit KenProblem statement: Flows of continuous-time dynamical systems with the same number of equilibrium points and trajectories, and which has no periodic orbit form an equivalence class under the topological conjugacy relation. Approach: Arbitrarily, two trajectories resulting from two distinct flows of this type of dynamical systems were written as a set of points (orbit). A homeomorphism which maps between these … …Journal of Mathematics and Statistics, Vol. 7, Issue 3 · 18 Jul 2011 · 7,259 accessesView PDF Cite

Research ArticleOpen accessTopological Conjugacy Between Seizure and Flat ElectroencephalographyTahir Ahmad, Tan Lit KenProblem statement: Seizure and Flat EEG which are modeled as two distinct dynamical systems share the same dynamics in the topological viewpoint. Approach: Motions of seizure and Flat EEG of the dynamical systems were written as set points. A function that maps between these two sets is then built. By using topological conjugacy, they are shown to share the same … …American Journal of Applied Sciences, Vol. 7, Issue 11 · 8 Nov 2010 · 6,765 accessesView PDF Cite

Research ArticleOpen accessGeneralized Finite Sequence of Fuzzy Topographic Topological MappingTahir Ahmad, Siti Suhana Jamian, Jamalludin TalibProblem statement: Fuzzy Topographic Topological Mapping (FTTM) was developed to solve the neuromagnetic inverse problem. FTTM consisted of four topological spaces and connected by three homeomorphisms. FTTM 1 and FTTM 2 were developed to present 3-D view of an unbounded single current source and bounded multicurrent sources, respectively. FTTM 1 and FTTM 2 were homeomorphic and this homeomorphism will generate … …Journal of Mathematics and Statistics, Vol. 6, Issue 2 · 30 Jun 2010 · 7,924 accessesView PDF Cite

Research ArticleOpen accessEEG Signals During Epileptic Seizure as a Semigroup of Upper Triangular MatricesFaisal Abdurabu Mubarak Binjadhnan, Tahir AhmadProblem statement: EEG signals during epileptic seizure can be presented as an algebraic structure, namely semigroup of upper triangular matrices. Approach: EEG signals during seizure were recorded and composed into set of matrices. They were transformed into upper triangular matrices using QR-Schur decomposition and finally as a semigroup of upper triangular matrices. Results: EEG signals during epileptic seizure were transformed … …American Journal of Applied Sciences, Vol. 7, Issue 4 · 30 Apr 2010 · 7,023 accessesView PDF Cite