Mühendislik Fakültesi / Faculty of Engineering
Permanent URI for this collectionhttps://hdl.handle.net/11727/1401
Browse
385 results
Search Results
Item Goodness-of-fit and Randomness Tests for the Sun's Emissions True Random Number Generator(2014) Tanyer, Suleyman Gokhun; Atalay, Kumru Didem; Inam, Sitki Cagdas; 0000-0003-0820-9186; I-5023-2013; JHU-3888-2023Random number generators ( RNGs) are one of the key tools necessary for statistical analysis and optimization methods such as Monte Carlo, particle swarm optimization ( PSO) and the genetic algorithm. Various pseudo and true RNGs are available today, and they provide sufficient randomness. Unfortunately, they generate data that do not always represent the required distribution accurately, especially when the data length is small. This could possibly threaten the 'repeatability' of an academic study. A novel true RNG ( TRNG) using the method of uniform sampling ( MUS) is recently proposed. In this work, the Sun's RF emissions MUS-TRNG is comparatively tested with well known pseudo and true RNGs. It is observed that both randomness and very high goodness-of-fit qualities are possible.Item True Random Number Generation of Very High Goodness-of-fit and Randomness Qualities(2014) Tanyer, Suleyman Gokhun; I-5023-2013The statistical nature of numerous problems in mathematics, physics and engineering have led to the development of methods for generating random data for a given distribution. Ancient methods include; dice, coin flipping and shuffling of cards. Today, various pseudo, quasi and true random generators ( RNGs) are being proposed for their improved properties. In this work, test metrics for goodness-of-fit and randomness are reviewed. The method of uniform sampling ( MUS) is modified for improving the randomness without harming the goodness-of-fit qualities. The test results illustrate that very high goodness-of-fit can be obtained even when the number of observed samples is as small as 10.Item Efficient Recognition of Human Emotional States from Audio Signals(2014) Erdem, Ernur Sonat; Sert, Mustafa; https://orcid.org/0000-0002-7056-4245; AAB-8673-2019Automatic recognition of human emotional states is an important task for efficient human-machine communication. Most of existing works focus on the recognition of emotional states using audio signals alone, visual signals alone, or both. Here we propose empirical methods for feature extraction and classifier optimization that consider the temporal aspects of audio signals and introduce our framework to efficiently recognize human emotional states from audio signals. The framework is based on the prediction of input audio clips that are described using representative low-level features. In the experiments, seven (7) discrete emotional states (anger, fear, boredom, disgust, happiness, sadness, and neutral) from EmoDB dataset, are recognized and tested based on nineteen (19) audio features (15 standalone, 4 joint) by using the Support Vector Machine (SVM) classifier. Extensive experiments have been conducted to demonstrate the effect of feature extraction and classifier optimization methods to the recognition accuracy of the emotional states. Our experiments show that, feature extraction and classifier optimization procedures lead to significant improvement of over 11% in emotion recognition. As a result, the overall recognition accuracy achieved for seven emotions in the EmoDB dataset is 83.33% compared to the baseline accuracy of 72.22%.Item Development of Computer Based Ballistocardiography System(2014) Ozturk, Nurhan; Yildiz, Metin; https://orcid.org/0000-0002-2554-6953; JJF-5070-2023Ballistocardiography is a measurement method which monitors physiologic parameters such as heart rate and respiration through measuring the vibrations caused by heart beat. In this study, a computer based system which enables monitoring the changes in the heart rate and respiration without any electrical connection with the patient is introduced. It is examined whether this system can be used in monitoring the heart beat velocity and respiration through making comparisons with a commercial data acquisition system. During the study, it is observed that heart beat velocity is determined with a maximum 5% error and respiration frequency with a maximum 5.8%. Furthermore, respiratory standstill can be detected with this system. According to these results, it could be concluded that the system can be used as pre-diagnosis with the aim of monitoring respiration disorders during sleep.Item Analysis of Heart Diseases from ECG Signal(2014) Kantar, Tugce; Koseoglu, Ovul; Erdamar, Aykut; https://orcid.org/0000-0001-8588-480X; AAA-6844-2019At the present time, the main method used in the diagnosis of heart disease is the electrocardiography (ECG). The purpose of this study is design a decision support algorithm which automatically detect the normal sinus rhythm or other pathologies. The improved algorithm will provide support to the doctor can be also used for educational purposes. Within the scope of this study, with the design of the rule based algorithm which automatically detect a normal sinus rhythm and non normal sinus rhythm, in total it can detect eight pathologies. In maincode there are thirteen functions that are used for diagnose eight different ECG pathology automatically. Higher success is being anticipated in future for the prediction power of the developed method with continuing research on the matter.Item A Feasibility Study of Communication with Cold Stimulations(2014) Budak, Erdem Inanc; Yildiz, Metin; https://orcid.org/0000-0002-2554-6953; JJF-5070-2023Some part of available sytems which requires surgery (kohlear implant) for communication of completely deaf people, other parts just heal for one side hearing impaired people (soundbite technologies). Thus, there are lot of research of tactiles that are methods for communication through skin. However, existing communication systems's speed are too low, also devices couldn't move because, they working with electricity and have big massive. In this paper we have developed alternative communication method that the system uses cold stimulus for transfer characters through skin and also first tests have been done. We used peltiers for exist to cold stimuli and developed a computer based control system to transfer to peltiers via coding. We saw that subjects perceived two stimulus per second at one point of their forearms. But when we used more than one stimulus for coding characters, perception percent get low. Overall of results, we prove that communication with thermal way is alternative method that gives promise.Item Classification of Patients with Heart Failure(2014) Bayrak, Tuncay; Ogul, Hasan; https://orcid.org/0000-0001-6826-4350; U-4603-2019Echocardiography is imaging of anatomy and physiology of heart with high frequency sound waves by using ultrasonic transducers. The signals obtained by using this method are defined as echocardiogram. In this way, the function of heart can be investigated and any abnormal case is determined according to many parameters. In this study, the classification was realized, according to 7 of features obtained from echocardiogram signals belong to 74 of patient in Machine Learning Repository (UCI) database. Naive Bayes was determined as the best classification method for this dataset and 63% sensitivity, 84% specificity, and an accuracy value of 77% has been reached. In conclusion, this study presents an investigation of determination of which features are significant in death based on heart failure.Item A New Approach to Fuzzy Initial Value Problem(2014) Gasilov, N. A.; Fatullayev, A. G.; Amrahov, S. E.; Khastan, A.; https://orcid.org/0000-0002-9955-8439; AEN-1756-2022In this paper, we consider a high-order linear differential equation with fuzzy initial values. We present solution as a fuzzy set of real functions such that each real function satisfies the initial value problem by some membership degree. Also we propose a method based on properties of linear transformations to find the fuzzy solution. We find out the solution determined by our method coincides with one of the solutions obtained by the extension principle method. Some examples are presented to illustrate applicability of the proposed method.Item Computational Prediction of MicroRNA Function and Activity(2014) Ogul, Hasan; 24272442Inferring microRNA (miRNA) functions and activities has been extremely important to understand their system-level roles and the mechanisms behind the cellular behaviors of their target genes. This chapter first details methodologies necessary for prediction of function and activity. It then introduces the computational methods available for investigation of sequence and experimental data and for analysis of the information flow mediated through miRNAs.Item Functional Copolymer/Organo-MMT Nanoarchitectures. XXII. Fabrication and Characterization of Antifungal and Antibacterial Poly (Vinyl Alcohol-co-Vinyl Acetate/ODA-MMT/AgNPs Nanofibers and Nanocoatings by e-Spinning and c-Spinning Methods(2015) Rzayev, Zakir M. O.; Erdonmez, Demet; Erkan, Kubra; Simsek, Murat; Bunyatova, Ulviye; 0000-0002-2904-3587Nanofibrous films and coatings were fabricated by electrospinning and centrifugal spinning of aqueous solutions of poly(vinyl alcohol-co-vinyl acetate)/octadecyl amine-montmorillonite layered silicate nanocomposites with/without in situ generated silver nanoparticles (AgNPs). Characterization of nanofibers were realized by FTIR, XRD, SEM, and thermal analysis methods. It was found that AgNPs significantly accelerated phase separation process providing fine distribution of nanofibers. Antifungal and antimicrobial activities of nanocomposites investigated by using Candida Spp fungals, G-positive and G-negative microorganisms strongly depended on chemical/physical structural factors, and loading silver species. Observed effective properties of nanomaterials can be employed for many applications (e.g., air filtration, food packaging, biomedical).