Graduate School of Natural and Applied Sciences
Permanent URI for this community
Browse
Browsing Graduate School of Natural and Applied Sciences by Title
Now showing 1 - 20 of 542
Results Per Page
Sort Options
Item A BIOINSPIRED CONCEPTUAL DESIGN METHODOLOGY FOR BIOROBOTS(2013-05-21) KONEZ EROĞLU, Aylin; ERDEN, Abdülkadir; ERDEN, ZühalThe main aim of this thesis is to develop a Bioinspired Conceptual Design (BICD) methodology for design of biorobots. Within the context of the dissertation, a novel BICD procedure has been developed based on existing BID approaches and systematic engineering design steps. This procedure is applied on several case studies, namely a dog biorobot (BioDog) for walking and trotting, a cockroach biorobot (BioCoc) for climbing, a jumping (grasshopper) biorobot for jumping and a hybrid (dog and lobster) biorobot for walking. A BICD process has been developed using the implementation results. Classic DEVS (Discrete Event System Specification) coupled model is used to formally represent the BICD process in order to develop a BICD methodology. The proposed BICD methodology transforms customer needs into a concept design of biorobot with clear and well-defined six design steps. In order to overcome the drawbacks of existing BIDs, the biological system analysis and the bioinspired transformation design steps have been considered in detail. In this thesis, although four case studies have been implemented to demonstrate the BICD methodology, fourteen biological systems and twenty four locomotion types are investigated by using content analysis and/or observation methods. The literature survey has been used for the content analysis method, while an experimental set-up is used to analyze the biological systems for the observation method. Required knowledge on morphology, function and behavior of biological systems are obtained using a high speed camera. During the bioinspired transformation step, the knowledge about the biological system has been transformed systematically into knowledge about the biorobots and this knowledge is used to develop the concept design of biorobots.Item A CASE STUDY FOR DESIGNING AN ADAPTIVE LEARNING ENVIRONMENT BY APPLYING VARK MODEL(2017-05-02) Jaballa, Rabieaa Abdusalam Massaud; Eryılmaz, MeltemThe styles of learning are personal traits that affect how students relate with their learning environment, peers, and instructor. Four of the most popular are reading / writing, visual, auditory and kinetic, which used by students to gain information. Number of students is visual learners, while others are kinesthetic or audio or read /write learners. While some other students use a combination all of them to gain information, they seem to have preferences in how to learn better. Teachers must teach as more of these preferences as possible, in order to assist students learn. Teachers can put together these learning styles into core curriculum activities so that students can succeed in their classes. This study shows some parts of development framework to identify students learning styles and combination it automatically. This system is based on VARK learning style model and VARK questionnaire to measure students’ learning styles, it is hosting by internet to help students to use it. This study has used a sample of participants that consisted of 50 of engineering students from Atilim University. In addition, this study contain, an experimental design with a pre-post test Control group was utilized. Accordingly analysis of the data, the results show that distribution for t-test for two groups (Control group and Experimental group) was normality distribution and it was determined that the difference in mean scores between the Experimental group and the Control group was significantly in help of the Experimental group and the achievement level in the Experimental group, which applied the VARK teaching model, was higher compared to the Control group. In addition, student satisfaction questionnaire instrument, 10-items that measure students’ satisfaction by using the system, as the results found that students’ satisfaction with the system was significant very high.Item A COMBINED APPROACH OF CLUSTERING AND ASSOCİATİON RULE MİNİNG FOR CUSTOMER PROFILING IN VIDEO ON DEMAND SERVICES(2022-01-24) Güney, Sinem; TURHAN, Çiğdem; PEKER, SerhatToday, IPTV (Internet Protocol Television) service providers offer VoD (Video on Demand) services as part of their business initiative toward generating more revenue. To do this, they need to know about customer behaviors and expectations. Such information related to users is stored in CRM (Customer Relationship Management) systems. Against this backdrop, the present work aims to analyze customers in VoD services with applying clustering and Association Rule Mining techniques. The LRFMP (Length, Recency, Frequency, Monetary, and Periodicity) model is applied to find out the customer behaviors, whereas the k means clustering algorithms allow for determining the number of clusters and customer profiles. As a result, four different customer groups are identified, namely as “consuming and most valuable”, “less consuming and less valuable”, “less consuming but loyal”, and “neither loyal nor valuable”. A major source of information for this study is the content type or genre as regards the content category and rental preferences of subscribers. To this end, the association rule algorithm (Apriori) is employed to predict the customers’ potential rentals. A combined approach as such would be useful for IPTV service providers to further shed light on precise customer behaviors and preferences, thus allowing to create more targeted marketing strategies for each category of subscribers in order to improve customer satisfaction and increase revenues in the long run.Item A COMBINED EXPERIMENTAL-NUMERICAL INVESTIGATION ON ALUMINIUM EXTRUSION(2011-04-27) KALKAN, Hakan; ÖZDEMİR, İzzet; BARANOĞLU, BesimThis study focuses on an industrial size aluminum extrusion process and consists of both experimental and computational parts. On the basis of process parameters and die geometry supplied by ASAŞ Aluminum Company, full scale computational models of the process have been constructed by using different commercial Finite Element and Finite Volume software packages. The necessary material characterization has been done by compression tests for which a new uni-axial compression test set-up suitable for high temperatures has been designed and manufactured. The measured load-displacement diagrams and exit temperatures are compared with the computational results. In addition to that, Finite Element and Finite Volume results are also compared. These results indicate that reasonable good agreement between the measured data and computational results can be achieved provided that the Finite Element Method is used and proper material characterization is conducted.Item A COMBINED NUMERICAL-EXPERIMENTAL INVESTIGATION ON MICRO-EXTRUSION(2013-06-14) MURAT, Levent; ÖZDEMİR, İzzet; ŞENGÖNÜL, MerihIn this work, to develop an understanding on micro forming processes, a combined experimental-numerical investigation on micro forming is presented. On the experi mental side, in order to demonstrate the statistical size effect, an experimental set-up for micro-extrusion has been designed and micro-extrusion test with copper billets of different average grain size, has been conducted successfully. On the modelling side, due to large displacement and large strains developing during the forming process, a geometrically non-linear continuum mechanics description is preferred. Since a grain level description is necessary for micro forming operations, crystal plasticity is used to model the mechanical response of each grain. To this end, the crystal plasticity framework has been coded as a user defined material model and integrated into the commercial FE software Abaqus as a UMAT subroutine. With this tool, a numerical investigation on the influence of grain orientations on frictional response at small scales is carried out.Item A COMPARATIVE STUDY OF COMMON CYBER SECURITY POLICIES FOR DIFFERENT ENTERPRISES(2022-02-28) SAMEER, MAHA; MISHRA, ALOKCCyber security represents the essential issue and takes the top priority not only for enterprises of all sizes but also national security. Nowadays, many enterprises invest heavily in cyber security to protect their cyber environments and information and communication technology. Therefore, several enterprises embrace security policies as one of security defense solutions to safeguard from any attacks before the damage is done and negative effect occurs on the business of the enterprise. In this study, significant and common cyber security policies of different enterprises are compared and discussed. These enterprises include health sector, financial sector, educational sector, aviation sector, and e-commerce. The purpose of this study is to build robust and inclusive cyber security in each company and enterprise. The result of this study indicates that there are ten important common security policies should be applied in each enterprise and organization. These policies include privacy policy, data protection policy, data retention policy, information security policy, E-mail security policy, physical security policy, website security policy, cloud security policy, network security policy, and access control policy. Additionally, results of this study show some cyber security policies to be more critical and important from enterprise to enterprise. That difference in priority of these security policıes depend on the nature of information under control enterprises and security needs of enterprises to these security policies.Item A COMPARATIVE STUDY OF CYBER SECURITY POLICIES(2017-06-02) Bderi,Haithem ABD Esharf; Mishra, AlokThe cyberspace is expanding faster than ever and with it cyber threats are also increasing making it imperative to have a strong cyber-security policy. Cyber-attacks don‘t only affect individual users and organization but can also cause national security issues. The different policies of different countries make it possible for hackers and intruders to carry cyber-attack while making it impossible for authorities to trace back offenders. It is important to develop a comprehensive Cyber-security policy to address all kinds of cyber threats so that every offender can be traced back and penalized accordingly. This research work examines and compares different attributes of cyber-security policies of selected countries. This research work identifies some important attributes which can help to develop an all-inclusive cyber security policy.Item A COMPARATIVE STUDY OF E-GOVERNMENT EVOLUTION IN AFRICA(2022-03-01) El-Asheibi, Nagat; Mishra, AlokStates are constantly striving to improve their services to their citizens, trying to reach them through the Internet in order to be able to explain their policies and be effective. The delivery of public information and services to citizens through the Internet channel is considered e-government. The e-government uses information technology to serve citizens, businesses and institutions. There are various factors that affect e-government. In general, researchers have examined e-government studies that have been put into practice by various African countries. The purpose of this study is to explore the possibilities offered by e-Government in Africa by documenting few initiatives on the continent that have developed innovative models that contribute to governments through the implementation. To achieve the aim of the thesis, we present former works and e-government evolution in Africa with discussion on the evolution of e-government in different African countries (Libya, Egypt, Botswana, Sudan, South Africa, Nigeria, Gambia, Ghana, Uganda, Kenya, and Mauritius).Item A COMPARATIVE STUDY OF NEURAL NETWORK APPROACHES IN NETWORK ANOMALY DETECTION(2022-02-15) Öney, Mehmet Uğur; PEKER, SerhatNetwork intrusion detection is an important research field, and artificial neural net works have become increasingly popular in this subject. Despite this, the research concerning comparison of artificial neural network architectures in the network in trusion detection is a relatively insufficient. To make up for this, this study aims to examine the neural network architectures in network intrusion detection to determine which architecture produces high accuracy and low false positive rate, and what are the effects of the architectural components such as optimization functions, activation functions, the momentum of the learning rate. For this purpose, we have generated 6480 neural networks and, we evaluated them KDD99 dataset and, near-real-time simulation environment. This thesis provides a roadmap to guide future research on network intrusion detection using artificial neural networks.Item A COMPARATIVE STUDY OF PRIVACY-PRESERVING TECHNIQUES FOR THE CLOUD STORAGE(2022-01-20) Al-Qaisi, Thr; Mishra, AlokInformation and data privacy have become critical concepts in the cloud computing industry, especially as internet users seek to use the cloud environment to store their personal and sensitive data. Many cloud service providers currently offer premium and quality-based services for their users as the first initiative for building a vast cloud community. However, security and privacy violations began to emerge and evolve in the cyber world and threaten most of its infrastructure. Fortunately, much research has been achieved to develop the proper techniques to overcome data privacy's perilous challenges and find better methodologies for protecting cloud storage contents. In this work, our study focuses on comparing several forms of privacy-preserving techniques for cloud storage. The study includes a comprehensive analysis of privacy-preserving techniques and their common attributes for the aim of designing flexible, secure, and efficient solutions for the dilemma that faces data privacy. We also present an attainable solution for privacy-preserving of the cloud storage by proposing a multi layer encryption framework with the use of one-time password authentication technology and a multi-cloud storage structure.Item A COMPARATIVE STUDY ON RESOURCE LEVELING CAPABILITIES OF COMMERCIAL PROJECT MANAGEMENT SOFTWARE PACKAGES FOR PROJECTS WITH RESOURCE CONSTRAINTS(2022-01-14) Hussein Farooq Albayati, Noor; Aminbakhsh, SamanIn construction project management the critical path method (CPM) is the most commonly used technique for project scheduling. Although this technique provides many advantages for project managers, it cannot efficiently deal with the allocation of the resources. Therefore, other techniques have been introduced to address resource allocation requirements of the projects. Of these techniques, Resource Leveling aims to minimize the fluctuation in resource usage histograms obtained by CPM without violating the resource constraints, while securing the shortest CPM duration. Resource leveling is vital for effective utilization of project resources (e.g., manpower, machinery, and equipment) as it helps precluding intermittent usage of the resources. Keeping the resource usage at a relatively constant level would result in a decrease in the overall project cost as the additional costs required to demobilize and remobilize the resources will be minimized. The main objective of this study is to analyze effectiveness and efficiency of the most widely used commercial project management software packages in solving resource leveling problems with constrained resources. To this end, the most recent versions – as per the date of this study – of three software packages, namely, Microsoft Project Professional 2019, Primavera P6 Professional 2019, and Asta Powerproject version 15.0.01.489 are examined. The performance of the practiced software are evaluated based on thirteen different priority rules over a set of problem instances available in the literature. The practiced problems include 640 instances providing a diverse combination of network complexity, activity number, and resource type number. Results obtained by the software are also compared with the solutions provided by the Serial Scheduling Scheme – a heuristic method. The findings of the leveling process reveal while all the three software packages manage to provide comparable results, Asta PowerProject transpire to be the all-round best performing method while Primavera sports the fastest leveling module. This study also sheds light on the challenges and practical hurdles to utilization of the aforementioned software for resource leveling purposes.Item A COMPARATIVE STUDY ON THE WAVE CLIMATE OF SOUTHERN AEGEAN COASTLINE OF TURKEY(2022-02-15) Al-Sammarraie, Khalooq Ahmed Alauldeen; Numanoglu Genç, Aslı; Balas, LaleIn this thesis, the wind and wave climate of southern Aegean Sea coastline of Turkey are studied. Six coastal areas to the South of İzmir Bay are selected for the analysis, namely as Kuşadası, Yalıkavak, Turgutreis, Marmaris, Fethiye and Datça coastal areas. In the wind climate analysis, the over land measurements of General Directoriate of Meteorology (GDM) are compared with the over sea wind estimates of European Centre for Medium-Range Weather Forecasts (ECMWF) operational archive. Additionally, the monthly maximum values of wind speeds are compared with the short-term over sea measurements of GDM. It is concluded that ECMWF over sea wind estimates present the wind conditions better than the over land and over sea wind measurements of GDM. In the wave climate analysis two methods are utilized. First, CEM empirical method is used to estimate the wave heights for the wave climate analysis. ECMWF wind predictions are selected in the CEM method. Secondly, the wave results of WAM numerical model are used for the wave climate analysis directly. In the wave climate the long term and extreme value statistics are studied. The significant wave height results of two methods from the long-term wave statistics are compared by studying nearshore and offshore locations for each coastal area. It is concluded that, for the nearshore part, WAM model gives lower wave heights than the CEM method. For the offshore part, WAM Model gives higher wave heights than the CEM Method, if the fetch lengths are relatively short. For the enclosed basins, it is seen that WAM model under estimates the wave heights, and therefore it is concluded that CEM Method gives more reliable results.Item A COMPARISON BETWEEN SOFT COMPUTING METHODS AND CONVENTIONAL (PID) CONTROLLER APPLIED TO A DC MOTOR SYSTEM(2014-06-09) DARBI, Fathi Mohamed A.; ALIEW, FuadThis research will compare the Soft computing techniques its advantages with the optimal proportional-integral derivative (PID) controller parameters, for control of a different parameters of a DC motor. The research approach is to establish superior features, including easy implementation, stable convergence characteristic and good computational efficiency. The methods for designing of PID Controllers will been compared and analyzed with the intelligent tuning techniques like Fuzzy Sets, Neural Networks and Genetic algorithms, Soft computing method was more efficient in improving the step response characteristics such as, reducing the steady-states error; rise time, settling time and maximum overshoot in position control of a DC motor.Item A COMPARISON OF IMAGE DETECTION ALGORITHMS YOLO AND FASTER R-CNN IN DIFFERENT CONDITIONS(2022-06-13) ABDULGHANI, ABDULGHANI MAWLOOD A.GHANI; Dalveren, Gonca Gökçe MenekşeIn this thesis, we compare YOLOv4 with YOLOv3 and Faster R-CNN in terms of better object detection in both challenging weather conditions and darkness. Moving objects such pedestrians, cars, buses and motorcycles can be difficult to detect in rainy, foggy and snowy weather conditions or even at night. This study is aimed at evaluating the three modules to determine which perform best in such circumstances, bearing in mind that none of them was initially intended to perform in bad weather conditions or at night. This Study is done by utilizing Tesla P4 GPU, with 12GB RAM. We trained these algorithms with an Open-Image dataset, where YOLOv4 has scored the best results at 40,000 iterations, 72 mAP, and 0.63 Recall. On the other hand, YOLOv3 has scored maximum at 36000 iterations, 65.53 mAP, and 0.54 Recall. Finally, Faster R-CNN scored 36,000 iterations, 51 mAP, and 0.49 Recall. In terms of detection performance evaluation, YOLOv4 performed at 42 FPS, while YOLOv3 was at 37 FPS and Faster R-CNN at 10 FPS in video with 30 FPS. Based on the results, YOLOv4 has performed the best in comparison to YOLOv3 and Faster R-CNN.Item A COMPARISON OF SQL AND NoSQL DATABASES(2022-02-25) RASHD, SOUAD RASHD ALİ; YAZICI, AliThis study comprises a research about both SQL and NoSQL databases and a comparison in terms of the advantages and disadvantages of each. The comparison is implemented depending on scalability, (ACID and CAP) theory, flexibility, performance, schema, query language, cost, speed and the stored data. We described briefly several examples of SQL databases including My SQL , MS-SQL Server Express Edition , Oracle 11g Express Edition Database. Also, the study included a description for many types of NoSQL database including Key-Value Store Database, Column-Oriented Database, Document Store Database and Graph Databases. The result of the study detected that SQL database is a table based database, supports flexibility, is vertical scalable, and utilizes Structured Language Query. On the other hand, the study discovered that SQL database is not a suitable choice for hierarchical data storage, etc. Whereas in terms of NoSQL, the study discovered that NoSQL databases are less flexible, however, horizontally scalable, have a non-structured querying language and is a good choice for hierarchical databases.Item A COMPONENT BASED MODEL DRIVEN SOFTWARE DEVELOPMENT FRAMEWORK FOR WEB-BASED APPLICATIONS(2017-01-07) Alrubaee, Afrah; Çetinkaya, DenizDeveloping a high quality, cost effective, reliable and on time software systems is a challenging task due to the large size and complexity of these systems. Traditional developing approaches that are concerned with constructing software systems from scratch cannot be suitable for dealing with this challenge. For that reason several approaches have been introduced to increase the productivity of the development. Two of these approaches are component based software engineering and model driven software development. Component based software engineering (CBSE) has been introduced as a solution for software reusability problem by using reusable software components to build new software system. Model driven development (MDD) is another approach in software development that was introduced to increase productivity and decrease the cost and effort. MDD aims to face the challenges of software development process through representing the essential aspects of the required system as models and generating the final source code from these models. The aim of this work is proposing a software development framework that combines MDD and CBSE approaches for merging the advantages and features of these approaches to facilitate software development. The framework is used successfully to develop an e-learning system as a case study. The framework was evaluated by making a comparison between existing component based software development process models and our framework.Item A DATA COLLECTION SYSTEM DESIGN FOR HAND GESTURES(2022-02-14) Akan, Erhan; Uslu, İbrahim Baran; Akagündüz, ErdemIn this study, we aim at designing a smart glove, which consists of different inertial sensors and an EMG sensor and developing a human-machine interaction application by pre-processing and fusing these different sensory data. We also aim at providing solutions in cases where image processing-based approaches are inefficient. In the proposed smart glove, the quartenion-based orientation data to be produced by the magnetometer and gyroscope together, the acceleration data to be generated by the accelerometer, and the analog data generated by the EMG sensor are collected and then prepared for use by different applications.Item A DATABASE DESIGN METHODOLOGY FOR COMPLEX SYSTEMS(2013-07-14) TOPALLI, Damla; ÇAĞILTAY, NergizThe quality of the software is directly related to addressing the users' needs and their level of satisfaction. To reflect user requirements to the software processes, correct design of the database model provides a critical stage during software development. Database design is a fundamental tool for modeling all the requirements related to users' data. The possible faulty conditions in database design have adverse effects on all of the software development processes. The possible faulty conditions can also cause continuous changes in the software and the desired functionality of the targeted system which may result in user dissatisfaction. In this context, reflecting the user requirements accurately in the database model and understanding of the database model correctly by every stakeholder involved in the software development process is the factor that directly affects the success of the software systems. In this study, a two-stage conceptual data modeling approach is proposed to reduce the level of complexity, to improve the understandability of database models and to improve the quality of the software. This study first describes the proposed two-stage conceptual data modeling. Then the proposed method’s impact on software engineers’ comprehension is also investigated and the results are examined. Results of this study show that, the proposed two-stage conceptual modeling approach improves the understanding level of software engineers and eliminates possible defects in this stage.Item A DECISION SUPPORT SYSTEM FOR MULTI-PROJECT CASH FLOW AND SCHEDULE RISK ASSESSMENT: CONTRACTOR’S PERSPECTIVE(2022-02-24) Yussef, Mohammed; Özkil, Altan; Sönmez, Rifat; civil engineeringThis thesis presents a Decision Support System (DSS) for multi-project cash flow and schedule risk assessment for contractors. The main objective of the proposed DSS is to develop a methodology which quantifies the cost and time uncertainty of multi projects for cash flow analysis, during bid stage from a general contractor’s perspective. The proposed methodology possesses necessary steps. The previous studies that focus on probabilistic cash flow management are reviewed to investigate the existing cash flow forecasting methods. Then a new methodology based on Monte Carlo simulation technique for DSS is presented for cash flow forecasting of multi projects. The advantages of the proposed methodology are demonstrated by the analysis of three real construction projects. Finally, scenario analyses are performed to determine the optimal project parameters that gives the best Net Cash Flow (NCF) forecasting by using proposed methodology. The main contribution of this thesis is that it enables integrated cash flow risk analysis of multiple projects simultaneously. This helps decision maker to adequately identify and manage multi-project risks related cost, schedule and cash flow.Item A FRAMEWORK FOR DESIGNING AN INFORMATION SYSTEM FOR DOWN SYNDROME PATIENTS(2022-02-15) AL-TAMEEMI, Haitham; Erkan, Turan Erman; Turhan, ÇiğdemThe possibility of setting up a framework for designing a new system for individuals with Down syndrome was studied. The idea behind this framework is to develop a remote monitoring system called Down Syndrome Information System (DSIS) that will contribute to improve the health status of individuals with Down syndrome, by allocating more resources to information technology. This framework is intended to guide developers to implement the proposed system in the future. The main objective of this thesis is to answer the question of can the proposed framework will be able to support the developers to design a DSIS. In order to answer this question, it is required to find answers to these other questions. 1) Can the proposed system satisfy end user's needs?; 2) Can the proposed system invest in IT in the healthcare field?; 3) Is the proposed system implementable by the developer? 4) What are the advantages between the newly proposed and the current system? The related works were surveyed and it was found that there is a lack in IT investment in health care services for people with Down syndrome. This lack became one of the main motivations for this thesis. In addition, the first three steps of system development life cycle approach (SDLC) will play a big role in setting the methodology of this framework. Questions 1 and 2 were addressed by the investigations illustrated. As for questions 3 and 4, they were answered by visualizing the proposed system to ensure implementing it. Limitations of this thesis include; 1) The proposed system is only applied for Down syndrome cases. 2) Using correlations functions as a statistical method to analyze the results of questionnaire form. 3) Using the first three steps of SDLC approach to set this framework. 4) Lastly, there are limitations related to the collections of feedbacks from some of Arabic countries including Iraq, and the dependent on journals and conferences for previous studies. This thesis will expected to contribute to set this framework as an educational guide for developers to build monitoring system for Down syndrome, build a hybrid system by involving the responsible people of Down syndrome in this system, and enhance the health status of individuals with Down syndrome.