Asaf Varol

Matepe University · Computer Engineering

Cloud computing technology has acquired a vast vogue in the business technology area over the years. It has offered huge services and features; however, many challenges affect enterprises to adopt cloud computing. The primary concerns are cost advantages and security risks. By conducting two types of surveys (interview, questionnaire), this rese...

The tourism industry is one of the important revenue sectors in today’s world. Millions of visits are made monthly to different countries across the planet. Some countries host more tourists than others, depending on the availability of factors that would fascinate visitors. Tourism demand can be affected by different factors, which may include gov...

Consumer reviews in the Airbnb marketplace are one of the key attributes to measure the quality of services and the main determinant of consumer rentals decisions. Such feedback can impact both a new and repeated consumer's choice decision. The way to manage poor reviews can help to save or damage the host's reputation. Sentiment analysis enables a...

Modeling and forecasting of tourism data have received attention in the past decades. Turkey is one of the countries that benefit significantly from the tourism industry. Several time series models have been recommended to best describe tourist arrivals to Turkey. However, in the 21st century, the world experiences great uncertainty in most possibl...

As automation is changing everything in today’s world, there is an urgent need for artificial intelligence, the basic component of today’s automation and innovation to have standards for software engineering for analysis and design before it is synthesized to avoid disaster. Artificial intelligence software can make development costs and time easie...

Bitcoin, the most well-known of all the cryptocurrencies , have attracted a lot of attention thus far, and their prices have been quite volatile. While some research employ traditional statistical and econometric methods to discover the factors that drive Bitcoin prices, experimenting on the development of prediction models to be utilized as decisi...

Internet of Things (IoT) plays a vital role in the existing and future generation of information, communication and applications. The 7th EAI International Conference on IoT as a Service (IoTaaS) aims to bring researchers, academicians, students, practitioners and professionals from academia and industry interested in creating IoT-based services. T...

The conference’s objective is to provide an international forum where researchers can present existing, evolving, or novel ideas, share their views, foster discussions and future collaborations among different stakeholders. The IoTaaS is seeking original research and industrial papers discussing IoT to address problems from various areas such as tr...

This study reviews crime scene investigation, collection of evidence and protecting evidence phases of digital forensic process based on the research in the literature. Using appropriate methods for collecting and protecting electronic evidence would contribute to digital forensics and information technology law. In order to have effective evidence...

Sentiments are the emotions or opinions of an individual encapsulated within texts or images. These emotions play a vital role in the decision-making process for a business. A cloud service provider and consumer are bound together in a Service Level Agreement (SLA) in a cloud environment. SLA defines all the rules and regulations for both parties t...

The Internet of Things (IoT) has revolutionized the human world by transforming ordinary everyday objects into smart devices. These autonomous devices have reshaped our lives. The emerging technology is expanding day-by-day with the increasing need for smart devices as so the issues are also increasing w.r.t security, data reliability, maintenance...

Tourism is counted as one of the most sensitive sectors to crises such as the COVID-19 pandemic. By the first quarter of 2020, it brought the foreign visitors' travels to a sudden and unexpected halt. This has negatively affected the tourism sector. Due to the perishable nature of the tourism industry products, many researchers are calling for urge...

Taking security measures against cyber-attacks has become a necessity for the whole world. Determining the most appropriate measures and their effective implementation form the basis of cyber security for all key institutions.This study, aims to demonstrate the appropriate analysis of cyber-attacks and analysis output models that facilitate fast an...

The perishable nature of tourism products and services makes forecasting an important tool for tourism planning, especially in the current COVID-19 pandemic time. The forecast assists tourism organizations in decision-making regarding resource allocations to avoid shortcomings. This study is motivated by the need to model periodic time series with...

Cloud Computing is one of the most emerging technologies that has transformed the macro world. The advent of cloud computing is not less than an evolution and miracle to the technology. It has made the on-demand availability of various scalable software resources possible over the internet. Although its extraordinary services and advantages like re...

Data mining and regression techniques are important methods that we can use to predict students’ performance to inform decision making. This study uses five regression techniques to analyse students’ first-year cumulative grade point average (CGPA) and predict their final graduation CGPA. The data set used in this study is that of programming and s...

Quality of Service (QoS) is a key factor for a viable Service Level Agreement (SLA) which ensures the formation of a reliable provider-consumer relationship in cloud computing. SLA ties up a service provider with a service consumer on agreed upon terms and conditions so that the provider’s promised services and the consumer’s requirements are fulfi...

Interpreting a speech signal is quite challenging because it consists of different frequencies and features that vary according to emotions. Although different algorithms are being developed in the speech emotion recognition (SER) domain, the success rates vary according to the spoken languages, emotions, and databases. In this study, a new lightwe...

When buying and selling cars, it can be a challenge to assign the correct price. Artificial neural networks, a branch of artificial intelligence, are frequently used for such calculations. In this study we designed two different artificial neural networks for car price forecasting and tested them using data from a car sales website. For data, a sof...

This survey investigates the characteristic flow, heat transfer and chemical reaction of Weissenberg and Williamson over a stretching sheet with thermal radiation and viscous dissipation. The nonlinear differential equation of the thermal boundary layer, which covers the physical problem, is derived and used to transform its equations into a system...

Ülkelerin birçoğu, doğa tarafından üretilen afetlerle karşı karşıya kalabilmektedir. Deprem, sel, heyelan, kasırga, kuraklık, yangın vb. olaylar en fazla karşılaşılan doğal afetler arasında yer almaktadır. Diğer taraftan insanların sebebiyet verdiği afetler de söz konusu olabilmektedir. Örneğin Amerika’da 9/11 diye adlandırılan ve 2001 yılında gerç...

E-mail is a very effective method for exchanging digital messages using computer-based devices. Since the beginning of 2015, statistics estimate that, on average, there have been around 205 billion e-mails sent per day. Unfortunately, e-mail has been used as a carrier for malicious and spam contents as well as a medium of various criminal activitie...

A good understanding of the computer basic block system is effective in students' understanding of computer usage and programming. This information is also necessary for choosing the right computer when purchasing a computer. Otherwise, the user may spend unnecessary money on a technology that he will not use. In this study, the basic components an...

Most of the home automation wireless technologies on the internet of things are based on ZigBee, Z-Wave, Wi-Fi, and Bluetooth wireless technologies. While these solutions are good enough, users of smart homes are facing challenges of selecting the best technology. This paper compares the performance of ZigBee, Z-Wave Wi-Fi and Bluetooth technologie...

This paper presents a complete overview of the storage landscape and cloud computing. It explains the major advantages and disadvantages of storing data online using cloud storage, how this works, and the basic concepts involved in cloud computing, while also demonstrating the layers of its architecture with reference to the Infrastructure as a Ser...

Ülkelerin birçoğu, doğa tarafından üretilen afetlerle karşı karşıya kalabilmektedir. Deprem, sel, heyelan, kasırga, kuraklık, yangın vb. olaylar en fazla karşılaşılan doğal afetler arasında yer almaktadır. Diğer taraftan insanların sebebiyet verdiği afetler de söz konusu olabilmektedir. Örneğin Amerika’da 9/11 diye adlandırılan ve 2001 yılında gerç...

Protecting the privacy of the information on mobile devices is highly important, both at present and also in the future, due to the significant role that mobile devices play in keeping and storing our sensitive data and information. This paper sheds light on the different and various usage of mobile phones in our daily life, as well as teaching the...

p class="0abstract">Thanks to rapid development of information technology there are many new tools that can be used for teaching and learning environment. In the long past, we had met classical classrooms where teachers had to use chalk to write done everything on the blackboard. Later, we have met new tools such as projection, desktop computers, s...

Market monopolies are one of the major threats for educational sector. To abide from market monopolies and employ internet resources, open source learning management systems are determining the technical factors in providing ideal solution for educational sector. Higher Education institution face defies to make suitable selection which fit to their...

Abstract— In the first part of this study, the basic concepts of forensic phonetics such as voice, speech, and voice track are explained. In the second part; visual and auditory montage detection methods used in forensic phonetics, one of the lower branches of digital forensics, were examined. The most frequently used visual and auditory analysis m...

Voice over Internet Protocol (VoIP) is one of the highly used applications for voice and data communication purposes. The convenience of using VoIP applications, its acceptable quality, and the relatively low cost of usage have made it a potential replacement for landline and cellular communication. Along with these advantages, the vulnerability of...

Mobile attack approaches can be categorized as Application Based Attacks and Frequency Based Attacks. Application based attacks are reviewed extensively in the literature. However, frequency based attacks to mobile phones are not experimented in detail. In this work, we have experimentally succeeded to attack an Android smartphone using a simple so...

Digital evidence plays a vital role in determining legal case admissibility in electronic- and cyber-oriented crimes. Considering the complicated level of the Internet of Things (IoT) technology, performing the needed forensic investigation will be definitely faced by a number of challenges and obstacles, especially in digital evidence acquisition...

Biometrics is the science that analyzes biological data and also the technology that measures biological data. Biometric systems make identification or identity verification by using measurable, distinctive physical and behavioral properties of humans. The most widely used biometrics techniques rely on finger prints, palm, hand geometry, iris, reti...

Trabzon–Tabriz Transit Commerce Road has been active since ancient times. One of the most important point of view of this route is the Trabzon port. This port is in a strategic position among all other ports in Black Sea. Turkey has invested in developing the infrastructure of this route both during Ottoman and Republican times in order to gain adv...

With an internet connection, criminals can now steal millions, buy and sell drugs, prey upon children from practically any location: their home, the public library, a coffee shop, the bus, a doctor's office, etc. In effect, the industry standard GPS electronic monitoring device alone no longer provides the information needed to detect unusual or de...

Türkiye Bilimsel ve Teknik Araştırma Kurumu (TUBITAK), 2003 yılında Ulusal Elektronik ve Kriptoloji Araştırma Enstitüsü'nü, dışa bağımlılıktan kurtulmak için bir milli işletim sisteminin yapılabilirliğini araştırmak üzere görevlendirmiştir. Bu proje Ulusal Dağıtım diye adlandırılmış ve yapılan çalışmalar sonucu 2005 yılında bu enstitü Pardus 1.0 ad...

In 2003, the Scientific and Technological Research Council of Turkey (TUBITAK) commissioned the National Research Institute of Electronics and Cryptology (UEKAE) in order to research feasibility of a national operating system for dependence from foreign countries. This project is called as National Distribution (Ulusal Dağıtım). In 2005, the projec...

As the number of social media users increases for platforms such as Twitter, Facebook, and Instagram, so does the number of bot or spam accounts on these platforms. Typically, these bots or spam accounts are automated programmatically using the social media site's API and attempt to convey or spread a particular message. Some bots are designed for...

The recent development in Information Communication Technology (ICT) has made changes in every aspect in our life. These changes are clearly reflected in cyberspace-related areas. The positive influence of cyberspace on knowledge, trade and business, and communication is undoubtable. However, there is a dark side of cyberspace deteriorates its peac...

Biometrics is a term used to define an individual's DNA, hand geometry, face, etc. or behavioral characteristics, such as hand signature, voice tone, keystrokes and so on. For that reason, these biological characteristics are unique for every individual. In many situations, face recognition related technologies are becoming more popular among biome...

In this paper, a novel nature inspired algorithm for continuous optimization of numerical functions has been proposed. The algorithm is inspired from the circular wave created from a water drop when it falls to a still water. Algorithm itself has been developed with the purpose of distributed working thus kept as embarrassingly parallel as possible...

Many mobile device makers now incorporate biometric security features into their products. And, some device manufacturers now allow application developers to use these features via their software development kits (SDKs). In this study, we utilize fingerprint scanning and recognition technology, a popular biometric security feature, to develop a web...

To store data and information on digital media and be accessible via the internet, makes the life easy. Lots of user save or share personal information on digital platforms which are defined as local or public source. Banks, government agencies, commercial organizations also store and operate institutional customers' information on digital systems....

In this paper, we describe the process by which Sam Houston State University, United States, (SHSU) and Firat University (FU), Turkey developed collaborative undergraduate degree programs in Software Engineering and Digital Forensics Engineering. The paper explores the administrative, curricular, accreditation, and financial issues that needed to b...

Diabetes is a disease that requires continuous monitoring and control. Patients and their families must rebuild their life according to the diabetes. In this study patient follow-up, control and routine medical examination have been actualized by an expert mobile system. In this study, the data about diabetes and its control, treatment and follow u...

Since students of online education do not meet face to face in a classroom environment, students get engaged to the classes via third party content or learning management tools. It is evident that young people spend most of their time on Social Networking websites when they are connected to internet. These sites provide free of speech environment w...

The Electronic commerce (e-commerce) which is the product of developments in the internet technology, It has been the place to commerce of the internet. In recent years, e-commerce with the significant development has shaped the economy of the 21st century. The development in e-commerce is brought together some questions, security issues and necess...

zetçe Parmak uzunluklarının kişisel davranışlara ve kişilerin yatkın olabileceği mesleki alanlar üzerindeki etkisi, gelişmekte olan bir araştırma çalışmasıdır. Bu deneysel çalışmada, 124 deneğin (70 kadın-54 erkek) sol ve sağ avuç içlerinin sayısal resimleri çekilmiştir. Analiz sonucunda p<0,05 dikkate alınarak, sağ el ile sayısal ve eşit ağırlık p...

Understanding and analyzing the difference between transformational and transactional leadership is crucial in getting the whole concept of leadership theories in organizations. Transformational leadership is the most popular theory which has evolved from the elements of leadership such as traits, situational and transactional leadership that focus...

ZET: Biyometrik sistemler, fiziksel özellikleri kullanılarak kiĢilerin elektronik ortamda tanınmasıdır. Biyometrik sistemler, bireylerden alınan örnekler ve uygulanacak algoritmalar ile birlikte bir depolama aygıtına saklanması sonrasında, verilerin eĢleĢtirme prensibi ile çalıĢmaktadır. GeliĢmiĢ ülkelerin birçoğu biyometrik sistemlerden yararlanar...

In this study virtual laboratory systems are investigated and effects of virtual laboratory systems on the robotics course that is worked at the Technology Faculties are discussed. For the application a SCORBOT-ER manipulation is used because this robot is expensive and it is very sensitive. The general purpose is become useful about effective lear...

In this study, first the system of promoting into associate professor degree is introduced, and some problems related to establishing of the juries of the candidates are discussed. Second, new database management software is created to automate the selection of jury process. The system holds keywords for linking the research fields of the juries an...

In this paper, it is proposed a new methodology based on invariant moments and multi-class support vector machine (MCSVM) for classification of human parasite eggs in microscopic images. The MCSVM is one of the most used classifiers but it has not used for classification of human parasite eggs to date. This method composes four stages. These are pr...

A numerical study has been performed to obtain combined convection field in an inclined porous lid-driven enclosures heated from one wall with a non-uniformly heater. The lid moves at constant speed and temperature. Darcy-Brinkman-Forchheimer model was adopted to write governing equations and they solved using finite volume method. A detailed param...

Steady state two-dimensional natural convection heat transfer was performed in triangular enclosures filled with porous media at different boundary conditions. Six different cases were tested based on all possibilities of temperature boundary conditions on vertical, bottom, and inclined walls of enclosure. Solutions of governing equations and linea...

A two-dimensional solution of natural convection in solid adiabatic thin fin attached to porous right triangular enclosures has been analyzed numerically. The vertical wall of the enclosure is insulated while the bottom and the inclined walls are isothermal. The temperature of the bottom wall is higher than the temperature of the inclined wall. Gov...

This paper presents a comparative study of implementation of feature extraction and classification algorithms based on discrete wavelet decompositions and Adaptive Network Based Fuzzy Inference System (ANFIS) for digital modulation recognition. Here, in first stage, 20 different feature extraction methods are generated by separately using Daubechie...

Free convection in a porous media filled triangular enclosure has been investigated to obtain the effects of different boundary conditions using a numerical technique. Two cases have been investigated: In the first case, bottom wall is heated while vertical wall is cooled. In the second case, the bottom wall is cooled and vertical wall is heated. I...

Millions of people in the world suffer from urinary incontinence and overactive bladder with the major causes for the symptoms being stress, urge, overflow and functional incontinence. For a more effective treatment of these ailments, a detailed understanding of the urinary flow dynamics is required. This challenging task is not easy to achieve due...

Steady-state free convection heat transfer in a right-angle triangular enclosure, whose vertical wall insulated and inclined and bottom walls are differentially heated, is performed in this study. The governing equations are obtained using Darcy model. In this study, the governing equations were solved by finite difference method and solution of al...