Search Results

Now showing 1 - 10 of 309
  • Article
    Citation - WoS: 12
    Citation - Scopus: 12
    Mutual Correlation of Nist Statistical Randomness Tests and Comparison of Their Sensitivities on Transformed Sequences
    (Tubitak Scientific & Technological Research Council Turkey, 2017) Doganaksoy, Ali; Sulak, Fatih; Uguz, Muhiddin; Seker, Okan; Akcengiz, Ziya
    Random sequences are widely used in many cryptographic applications and hence their generation is one of the main research areas in cryptography. Statistical randomness tests are introduced to detect the weaknesses or nonrandom characteristics that a sequence under consideration may have. In the literature, there exist various statistical randomness tests and test suites, defined as a collection of tests. An efficient test suite should consist of a number of uncorrelated statistical tests each of which measures randomness from another point of view. `Being uncorrelated' is not a well-defined or well-understood concept in the literature. In this work, we apply Pearson's correlation test to measure the correlation between the tests. In addition, we define five new methods for transforming a sequence. Our motivation is to detect those tests whose results are invariant under a certain transformation. To observe the correlation, we use two methods. One is the direct correlation between the tests and the other is the correlation between the results of a test on the sequence and its transformed form. In light of the observations, we conclude that some of the tests are correlated with each other. Furthermore, we conclude that in designing a reliable and efficient suite we can avoid overpopulating the list of test functions by employing transformations together with a reasonable number of statistical test functions.
  • Article
    Health Beliefs and Attitudes: a Comparison Between Turkey and Palestine
    (Routledge Journals, Taylor & Francis Ltd, 2018) Menawi, Wafaa Allam; Tengilimoglu, Dilaver; Dziegielewski, Sophia F.
    The purpose of this study is to identify the beliefs and attitudes that influence health-related behavior while comparing two countries that can have different political and economic structures. This study also gathers both Turkish and Palestinian citizens' beliefs and attitudes towards health determinants. To assess and compare citizens' attitudes toward health care and health determinants a total of 4,100 questionnaires were distributed, whereas 2,600 were distributed in Turkey, and another 1,500 questionnaires in the Palestine. According to the research, the individuals surveyed in Turkey noted that smoking, stress, and getting access to a medical institution were noted as the most influential determinants which affect their health; whereas, the people of Palestine thought that income status, and educational levels were the most influential factors in health. In addition, it was found that there were some statistically significant differences between participants' responses in Turkey and Palestine; however, what both samples shared was that economic factors were an important factor affecting health beliefs and attitudes, regardless of where a participant lived. Finally, comparisons and future recommendations are made to improve health-related beliefs, attitudes and behaviors in both countries.
  • Article
    Patient Safety in Healthcare: A Proposal for Ensuring the Use of Regulation-Compliant Safety Devices
    (Springer Heidelberg, 2025) Bayrak, Tuncay
    Medical devices used in health care should fulfill the requirements of the technical regulations to protect patient health. Difficulties in enforcing stricter rules in the new medical device regulations may negatively affect the continuity of care. This study examines the status of manufacturers' compliance with medical device regulations, based on predefined criteria, and proposes a collaborative action plan and an approach to verify regulatory compliance. We conducted a nationwide survey comprising questions grouped by criteria to understand the status of the manufacturers in terms of compliance with the Medical Device Regulation. Four hundred sixty-seven manufacturers participated in the survey. We achieved a Cronbach's alpha of 0.77, which indicates that the survey is statistically reliable. We applied the independent samples t-test to the responses to determine significant features per question and employed factor analysis to investigate the relationships of the questions. The results of independent samples t-tests showed statistically significant differences across groups in replies to several survey items (p < 0.05), indicating that participants' opinions varied based on their demographic characteristics. We applied Exploratory Factor Analysis to introduce the relationships between the questions. The analysis revealed that manufacturers continue to face substantial challenges in acquiring sufficient knowledge and operational capability to meet MDR requirements. In light of these findings, we focused on the person responsible for regulatory compliance, who plays a central role in maintaining regulatory compliance within manufacturing organizations. We proposed an action plan at the macro level to introduce more effective action plans in cooperation with other stakeholders, including healthcare providers, and a verification approach for regulatory compliance to enhance the Person Responsible for Regulatory Compliance's competence. Manufacturers should implement effective postmarketing clinical follow-up plans involving device-oriented parameters for monitoring in the healthcare system, especially in collaboration with health professionals.
  • Review
    Citation - WoS: 16
    Citation - Scopus: 20
    Assessing the Coverage of E-Health Services in Sub-Saharan Africa a Systematic Review and Analysis
    (Georg Thieme verlag Kg, 2017) Adeloye, Davies; Adigun, Taiwo; Misra, Sanjay; Omoregbe, Nicholas
    Background: E-Health has attracted growing interests globally. The relative lack of facilities, skills, funds and information on existing e-Health initiatives has affected progress on e-Health in Africa. Objectives: To review publicly available literature on e-Health in sub-Saharan Africa (sSA) towards providing information on existing and ongoing e-Health initiatives in the region. Methods: Searches of relevant literature were conducted on Medline, EMBASE and Global Health, with search dates set from 1990 to 2016. We included studies on e-Health initiatives (prototypes, designs, or completed projects) targeting population groups in sSA. Results: Our search returned 2322 hits, with 26 studies retained. Included studies were conducted in 14 countries across the four sub-regions in sSA (Central, East, South and West) and spreading over a 12-year period, 2002-2014. Six types of e-Health interventions were reported, with 17 studies (65%) based on telemedicine, followed by mHealth with 5 studies (19%). Other e-Health types include expert system, electronic medical records, e-mails, and online health module. Specific medical specialties covered include dermatology (19%), pathology (12%) and radiology (8%). Successes were 'widely reported' (representing 50% overall acceptance or positive feedbacks in a study) in 10 studies (38%). The prominent challenges reported were technical problems, poor inter net and connectivity, participants' selection biases, contextual issues, and lack of funds. Conclusion: E-Health is evolving in sSA, but with poorly published evidence. While we call for more quality research in the region, it is also important that population-wide policies and on-going e-Health initiatives are contextually feasible, acceptable, and sustainable.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 20
    Reinforcement Learning Using Fully Connected, Attention, and Transformer Models in Knapsack Problem Solving
    (Wiley, 2022) Yildiz, Beytullah; Yıldız, Beytullah; Yıldız, Beytullah
    Knapsack is a combinatorial optimization problem that involves a variety of resource allocation challenges. It is defined as non-deterministic polynomial time (NP) hard and has a wide range of applications. Knapsack problem (KP) has been studied in applied mathematics and computer science for decades. Many algorithms that can be classified as exact or approximate solutions have been proposed. Under the category of exact solutions, algorithms such as branch-and-bound and dynamic programming and the approaches obtained by combining these algorithms can be classified. Due to the fact that exact solutions require a long processing time, many approximate methods have been introduced for knapsack solution. In this research, deep Q-learning using models containing fully connected layers, attention, and transformer as function estimators were used to provide the solution for KP. We observed that deep Q-networks, which continued their training by observing the reward signals provided by the knapsack environment we developed, optimized the total reward gained over time. The results showed that our approaches give near-optimum solutions and work about 40 times faster than an exact algorithm using dynamic programming.
  • Article
    Citation - WoS: 22
    Citation - Scopus: 23
    On Residual Lifetime of Coherent Systems After the rth Failure
    (Springer, 2013) Eryilmaz, Serkan
    In this article we study the residual lifetime of a coherent system after the rth failure, i.e. the time elapsed from the rth failure until the system failure given that the system operates at the time of the rth failure. We provide a mixture representation for the corresponding residual lifetime distribution in terms of signature. We also obtain some stochastic ordering results for the residual lifetimes.
  • Article
    Citation - WoS: 29
    Citation - Scopus: 36
    Massive Mimo Systems for 5g: a Systematic Mapping Study on Antenna Design Challenges and Channel Estimation Open Issues
    (inst Engineering Technology-iet, 2021) Benzaghta, Mohamed; Rabie, Khaled M.
    The next generation of mobile networks (5G) is expected to achieve high data rates, reduce latency, as well as improve the spectral and energy efficiency of wireless communication systems. Several technologies are being explored to be used in 5G systems. One of the main promising technologies that is seen to be the enabler of 5G is massive multiple-input multiple-output (mMIMO) systems. Numerous studies have indicated the utility of mMIMO in upcoming wireless networks. However, there are several challenges that needs to be unravelled. In this paper, the latest progress of research on challenges in mMIMO systems is tracked, in the context of mutual coupling, antenna selection, pilot contamination and feedback overhead. The results of a systematic mapping study performed on 63 selected primary studies, published between the year 2017 till the second quarter of 2020, are presented. The main objective of this secondary study is to identify the challenges regarding antenna design and channel estimation, give an overview on the state-of-the-art solutions proposed in the literature, and finally, discuss emerging open research issues that need to be considered before the implementation of mMIMO systems in 5G networks.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Synthesis and Characterization of New Dithienosilole Based Copolymers
    (Electrochemical Soc inc, 2016) Karabay, Lutfiye Canan; Al-Jumaili, Mohammed; Cihaner, Atilla
    2-Ethylhexyl substituted dithienosilole based soluble polymers including thiophene (1) and bithiophene (2) units were synthesized via Stille coupling reaction. The presence of 2-ethylhexyl substituents on the silole ring gave solubility property to the polymers in common solvents. According to gel permeation chromatography measurements, the weight average molecular weights of the polymers 1 and 2 were found to be as 70,977 with a polydispersity index of 2.30 and 110,439 with a PDI of 1.42, respectively. Fluorescent polymers in toluene solution have maximum emisssion bands at 634 nm for the polymer 1 and 613 nm for the polymer 2. Chemical and electrochemical doping of the polymers in the solution and in the film forms were monitored by using ultraviolet-visible spectroscopic technique. The polymers exhibited chromic (chemochromic and electrochromic) properties. While the colors of the neutral polymer films are purple for the polymer 1 and reddish brown for the polymer 2, both polymers are transparent sky blue at their oxidized states. The bandgaps of polymers in film forms were calculated as 1.81 eV for the polymer 1 and 1.92 eV for the polymer 2. Also, electrochromic device applications of the polymers were done. Electrochemical and optical behaviors of the polymers demonstrated that they can be good candidates for optoelectronic applications. (C) 2016 The Electrochemical Society. All rights reserved.
  • Article
    Citation - WoS: 8
    Citation - Scopus: 18
    Featuring Cio: Roles, Skills and Soft Skills
    (Igi Global, 2013) Cano, Carmen; Fernandez-Sanz, Luis; Misra, Sanjay
    This paper describes how the CIO (Chief Information Officer) position appears as a key role in the organizations and the requirements for candidates. The authors compare the requirements presented in different studies to know what are the most important skills for a successful performance as a CIO. They stress the importance of non technical skills as key factors for professional performance. The authors have compared soft skills for CIO or equivalent positions and other professional profiles like programmers or analysts using data taken from thousands of job ads. An overview of the most valuable skills (especially soft skills) for CIOS is presented.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Machine Vs. Deep Learning Comparision for Developing an International Sign Language Translator
    (Taylor & Francis Ltd, 2022) Eryilmaz, Meltem; Balkaya, Ecem; Ucan, Eylul; Turan, Gizem; Oral, Seden Gulay
    This study aims to enable deaf and hard-of-hearing people to communicate with other individuals who know and do not know sign language. The mobile application was developed for video classification by using MediaPipe Library in the study. While doing this, considering the problems that deaf and hearing loss individuals face in Turkey and abroad modelling and training stages were carried out with the English language option. With the real-time translation feature added to the study individuals were provided with instant communication. In this way, communication problems experienced by hearing-impaired individuals will be greatly reduced. Machine learning and Deep learning concepts were investigated in the study. Model creation and training stages were carried out using VGG16, OpenCV, Pandas, Keras, and Os libraries. Due to the low success rate in the model created using VGG16, the MediaPipe library was used in the formation and training stages of the model. The reason for this is that, thanks to the solutions available in the MediaPipe library, it can normalise the coordinates in 3D by marking the regions to be detected in the human body. Being able to extract the coordinates independently of the background and body type in the videos in the dataset increases the success rate of the model in the formation and training stages. As a result of an experiment, the accuracy rate of the deep learning model is 85% and the application can be easily integrated with different languages. It is concluded that deep learning model is more accure than machine learning one and the communication problem faced by hearing-impaired individuals in many countries can be reduced easily.