Graduate School of Informatics /Cognitive Science

In partial fulfillment of the requirements for the degree of Master of Science Çağdaş Bostancı will defend his thesis.

Title: TEMPORAL AND STRUCTURAL PERCEPTION OF RHYTHMIC IRREGULARITIES

Date: 29th May 2018

Time: 09:30 AM

Place: B-116

Thesis Abstract :Time perception studies often seek for a timing mechanism that can explain temporal judgments in a general way. In search of such a model, environmental, contextual and subjective factors affecting temporal judgments should be taken into account as well. The present study provides a critical evolution of existing timing models by comparing the interval processing and production strategies of musicians and non-musicians. The study contains 3 experiments: Experiment 1 is a perceptual comparison task, Experiment 2 is a duration reproduction task and Experiment 3 is a rhythm reproduction task. The contrasts between the two groups are believed to be captured by participants’ initial reactions to rhythmic structures. For that purpose, short scale (4 beat) rhythmic samples are used in the experiments. Standard samples are regular 4 beat rhythms. Test samples include regular and irregular rhythms. The irregular conditions are prepared by changing the temporal position of the second beat of the regular rhythms. Early and late second beats in these irregular samples have the same temporal distance from the expected beat. Hence, the expectancy violation reflects any differences between early and late oddball stimuli. The experimental analyses suggest an asymmetry between early and late oddballs in participants’ initial reactions to such expectancy violations, in terms of their perceptual comparison of rhythms, as well as their duration and rhythm (re)production. Moreover, it provides evidence for different strategies used by participant groups in order to cope with rhythmic irregularities.

Title: Player Acceptance and Motivation for Games with Emerging Technologies: A Multi Theory Approach in Virtual Reality Gaming and Pervasive Gaming Contexts

PhD Candidate: Mehmet Kösa

Program: Information Systems Department 

Date: 04 June Monday 14:00

Place: Conference Hall-01

Abstract: The research project presented here consists of the studies I undertook throughout my PhD studies. In this research project, I propose a gaming technology acceptance-motivation model (GTAM). The model amalgamates Technology Acceptance Model, Self-Determination Theory and Flow Theory. The aim of the model is to expand knowledge on the acceptance of and motivation for video gaming technologies. Initially, a systematic literature review was conducted to see the state of the art research on hedonic information systems in the information system (IS) literature. The literature review produced salient research question and the results were presented in the light of those research questions. Building on the literature, the model was created. The proposed model was tested using quantitative methods. Data collection was two-fold: First, a cross-sectional survey was carried out in the virtual reality (VR) gaming context and then, a longitudinal diary study was conducted in the pervasive gaming (PG) context to complement the survey. For the survey, structural equation modeling was employed and for the diary study, multilevel analyses were conducted. Therefore, the proposed model was tested with two empirical studies. Results showed that perceived ease of use was the antecedent of autonomy and competence. Also, in addition to flow (immersion and concentration), autonomy and competence predict enjoyment which then predicts attitude and intention play. Studies presented offer theoretical contributions to IS and games research as well as implications for managers and practitioners in the interactive hedonic information system business. The results were discussed and the implications were presented.

Graduate School of Informatics /Information Systems

In partial fulfillment of the requirements for the degree of Master of Science Mehmet Erdem Örs will defend his thesis.

Title: ACCEPTANCE OF MOBILE PAYMENT TECHNOLOGIES: THE STATE-OF-THE-ART AND PROPOSED MODEL

Date: 05th May 2018

Time: 15:00 AM

Place: A-108

Thesis Abstract : This thesis aims to develop a technology adoption model by inspecting acceptance of mobile payment (MP) systems literature from different perspectives. This study can be divided into two main parts. In the first part of the thesis, acceptance of mobile payment systems is examined in detail. In the second part, a technology acceptance model is developed by using the findings of literature. Related literature is reviewed from 2005 to end of March 2018. Literature review provides information about studies’ location, sample size, theoretical background, research method, statistical analyses, constructs and significant relationships. As a result of literature review, 11 factors are derived. The factors are validated by an expert panel. Afterwards, a technology acceptance model is proposed based on analysis of the literature. To test the hypotheses of model, a measuring instrument (questionnaire) is formed. Data is collected from 378 participants, however 302 of them are used in the analyses. The model is tested by employing Partial Least Squares – Structural Equation Modelling (PLS-SEM). After obtaining results, inter-factor relations are added to the model from literature for testing. In the end, final version of the model is created. Results are fortified with interviews made with participants of the questionnaire. Final findings show that, use of mobile payment systems is affected most by usefulness and compatibility

Title: A PRACTICAL MEASUREMENT CAPABILITY MODEL FOR SOFTWARE ORGANIZATIONS UTILIZING AGILE APPROACHES

PhD Candidate: Murat Salmanoğlu

Program: Information Systems Department 

Date: 16 April Monday 09:00

Place: Conference Hall-01

Abstract: Measurement is the foundation for successful software management. However, it is not easy for software organizations to evaluate their measurement practices and to determine what they should do to improve them. There are models to evaluate capability and maturity of measurement processes. However, they frequently focus on the measurement process with a guidance from a well-defined capability model, like CMMI or SPICE. Many of the software organizations following agile methodologies do not prefer to apply these process-centric maturity models. This study presents a model to assess measurement capability of software organizations by inspecting individual measures, independent from the software development approach and the process architecture organizations use. The model exemplifies measures for aspects and defines generic practices for three capability levels. Organizations can use the model to determine and improve their measurement capability. This research includes action research and exploratory case studies conducted during the development of the model, an explanatory case study conducted to implement the model, and its results. Case studies demonstrate that the model provides additional benefits to organizations utilizing agile approaches while providing similar results with the process-centric models. The findings of the explanatory case study indicate that the results of the model are accepted and found beneficial by the employees from small-, medium- and large-scale organizations that participate in the study.

Title: SYNTACTIC PRIMING OF RELATIVE CLAUSE ATTACHMENT IN MONOLINGUAL TURKISH SPEAKERS AND TURKISH LEARNERS OF ENGLISH

PhD Candidate: Zeynep Başer

Program: Cognitive Science Department 

Date: 24 April Tuesday 10:00

Place: Conference Hall-01

Abstract: The purpose of this study is to investigate the syntactic priming of relative clause attachment in monolingual Turkish speakers and Turkish learners of English with different levels of proficiency in English. Syntactic priming is the facilitation of processing which occurs when a sentence has the same syntactic form as a preceding one. Within the last three decades, a manifold of studies have investigated the phenomenon, especially with native speakers of various languages, yet there is a quite low number of research with monolingual Turkish speakers and Turkish learners of English.Turkish and English belong to typologically different groups of languages. Within the scope of this study, we investigate syntactic priming of relative clause attachments, which enables us to examine and compare the strategies employed for ambiguity resolution both in Turkish and English. The data was collected through offline (pen-and-paper), online (self-paced reading), and eye-tracking studies. The analysis of the data revealed important findings about the parsing strategies employed by both monolingual Turkish speakers and Turkish learners of English. The role of several confounding factors on RC attachment preferences was identified, such as the role of (i) animacy / inanimacy information embedded in the host NPs, (ii) semantic relations between the host NPs, (iii) the semantic associations of the host NPs with the proximal and the distal predicate, and (iv) active / passive RC condition. Furthermore, the relation between working memory capacity and RC attachment preferences was analysed. Besides, effects of methodological issues, such as the presentation mode (i.e. full sentence or phrase-by-phrase), techniques (i.e. offline, online, or eye-tracking), task requirements (i.e. implicit processing or directed assessment of the syntactic structure in the prime) and modality(comprehension or production) were compared.

Graduate School of Informatics /Health Informatics

In partial fulfillment of the requirements for the degree of Master of Science Ahmet Levent Kandemir will defend his thesis.

Title: RESTING STATE BRAIN CONNECTIVITY VIA BICOHERENCE AND COHERENCE

Date: 21th March 2018

Time: 14:00 AM

Place: B-116

Thesis Abstract : Bicoherence is normalized version of bispectrum. Bispectrum is known as decomposition of the third moment (skewness) of a signal over frequency, and falls in the category of higher-order spectra. It provides supplementary information to the power spectrum and is proven to be useful in various fields of science such as sonars, biomedical engineering, radars etc. Despite this, the extensive computations required for processing of multidimensional data make bispectrum less practical than other methods in signal processing. In this study, information content of bicoherence will be evaluated. The aim is to find a time saving alternative to multidimensional bicoherence estimation. Alternatives will be compared to well known connectivity metric know as coherence. During study, methods will be applied on Resting State MEG data from Human Brain Connectome Project which can be found online.

Graduate School of Informatics /Cognitive Science

In partial fulfillment of the requirements for the degree of Master of Science uğur Acar will defend his thesis.

Title: COGNITIVE ASPECTS OF BRAIN-COMPUTER COMMUNICATION: AN IMPLEMENTATION AND EXTENSION OF THE P300 SPELLER PARADIGM

Date: 15th March 2018

Time: 09:00 AM

Place: A-108

Thesis Abstract :Recently, advances in Brain Computer Interface (BCI) Devices have enabled access by a wider population of end users. Such devices are usually based on neuroimaging techniques such as Electroencephalography (EEG), which pick up characteristic brainwave signatures such as P300 event-related potentials (ERP). In this model, three types of stimuli will be presented. The first type are alphabet letters, the second type are symbols for basic needs, and the last type are words for creation of sentences. Simple sentences may be created including subject, object, and verb. Technically the present model has two parts, a training phase and a testing (prediction) phase. In the training phase, the user concentrates on one of the stimuli among the entire set of alternative stimuli and the application detects a P300 ERP for that target stimulus which captures the selection of the subject. The training phase is used for understanding the neural patterns of each user and thus, it generates a user-specific training model. After the completion of the training phase, the subject will be able to use the application for communication purposes. In the subsequent test phase, the subject will carry out two sets of tasks. First, subjects will use the three sets of items (letters, icons, and words), and create pre-specified target items, e.g., words (from letters), icon sequences, and sentences (from words). In case of incongruence of the intended and the produced item (by the application), a N400 ERP is expected, which will be statistically analyzed. Second, subjects will be given a number of action assignments for whose realization they are free to choose any of the three sets of units (letters, icons, and words). Cognitive strategies underlying the choice of units for efficient communication will be analyzed. In sum, the proposed thesis aims at combining technical and cognitive aspects of the usage of BCI devices for communication.

Graduate School of Informatics /Information Systems

In partial fulfillment of the requirements for the degree of Master of Science Bengül Bayraktaroğlu will defend his thesis.

Title: "USER MOBILITY BASED AUTHENTICATION AND CLOUD MOCKING" 

Date: 25th January 2018

Time: 10:30 AM

Place: A-108

Thesis Abstract :

Small and Medium-sized Enterprises (SMEs) from different business sectors, that are certified by some standardization organizations, are increasingly prioritizing the process improvement to raise their product’s quality. The process improvement in SMEs has focused principally on the refinement of existing processes to improve what is currently done through the application of previously developed tools and techniques. This thesis study describes the application of Soft Systems Methodology (SSM) for engineering design process improvement in a SME that has the certification of Capability Maturity Model Integration (CMMI). The SSM uses systems thinking in a cycle of action research and learning to help understand the various perceptions that exist in the minds of different people involved in the problematic situations. In the concept of thesis study, it will lead to identify problematic situations about design process and its sub-processes by involving the human, social and cultural factors besides the technical factors. This thesis study includes four case studies of SSM’s use to analyze the sub-processes of design process named as Requirements Management, Technical Solution, Integration, Verification and Validation sub-processes. There are seven stages of SSM and they are applied to design process and its sub-processes except the stage seven, implementation stage. The rich pictures of sub- processes are drawn based on gathered data from semi-structured interviews and then the root definitions are defined by using CATWOE rule. The conceptual models are built for sub- processes and they are compared with real world activities to address the proposed changes. The outcomes of the study will show how the rich pictures, root definition and conceptual models approaches of SSM can help to identify the problematic situations and address the proposed changes.

Graduate School of Informatics /Information Systems

In partial fulfillment of the requirements for the degree of Master of Science Fatih Ünver will defend his thesis.

Title: "USER MOBILITY BASED AUTHENTICATION AND CLOUD MOCKING" 

Date: 19th January 2018

Time: 14:30 AM

Place: A-108

Thesis Abstract :

Nowadays, mobile phones are widely used and carried by people almost all the time of a day. Also, people spend lots of time using these devices and applications inside. It means that these devices keep our personal data like application usage or environmental measurements that are produced and stored by build-in sensors on mobile devices even we do not use the device. This data can describe mobility of a human being easily. In this thesis, a cross-platform application that collects application usage statistics and sensory data and sends to the cloud periodically is developed. Then a virtual profile is created according to the data on cloud. Whenever user is trying to open an application, cloud looks previous mobility records of the user and decides whether this operation and environment is typical or not. This structure is applicable for multi-level authorization. Since the application needs to many cloud communication, we have also developed a cloud mocking framework. This framework can automatically create unit tests for all possible exceptions and success scenarios and these cases can be run and test without a real cloud connection. This framework is created to save time and effort in development and unit testing.

Graduate School of Informatics /Information Systems

In partial fulfillment of the requirements for the degree of Master of Science Fatih Kurt will defend his thesis.

Title: "ONTOLOGY GUIDED NEURAL NETWORK PROCESSING FOR AUTOMATIC IMAGE CAPTION GENERATION" 

Date: 24th January 2018

Time: 10:00 AM

Place: A-212

Thesis Abstract :

A fundamental problem in artificial intelligence is automatically describing the content of an image since it will help to identify objects with computer vision and create meaningful rich descriptions using natural language processing. At the same time, searching for an image with a description is another key element in proving theory work vice versa. In this work, ontology guided neural network processing will be used to further improve previous work regarding to image caption generation. By using ontology, more reliable results could be deducted from neural network processing by associating objects and their activities with vector results. Final trained system is expected to better process visual input and create better descriptions for images by also using RNNs(recurrent neural networks); thus, the work is aimed at further improving BLEU score of earlier works.