Computer Technology and Information Systems

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  • ItemMetadata only
    Software quality and model-based process improvement
    (CRC Press, 2022-05-30) Bariş, Özkan; Albayrak, Özlem; Demirörs, Onur; Albayrak, Özlem
    In this chapter, we introduced software quality and model based process improvement. Quality is more and more often seen as a critical software attribute and a determinant of business success. The absence of quality in software products and services results in dissatisfied users, financial loss, and may even endanger to our lives. SPI is a process oriented approach to address quality problems. We presented underlying principles by focusing on quality, process and quality, and the Co Q. We explained quality using different defining approaches, such as transcendental, product, user, manufacturing, and value based approaches. We then defined process and qualitystartingwiththeconceptofprocessaswidelyappreciatedastheproper ground for improving product quality and productivity. We highlighted the importance of SPC, plan do check act, and TQM. We also explained Co Q. Co Q analysis and technique shave been in use for more than 50 years and there are multiple models for Co Q. These models are the effective tools in feasibility analysis of SPI programs and the measurement and evaluation of the program performance. Both theory and experience advise investing on prevention and appraisal costs to get the highest returns from the decreased costs of appraisal and failure. In terms of best practices, we focused on software process maturity, models for SPI, and results from implementations. The use of maturity models has been popularized in software engineering through the SEI software CMM, which was published in 1991. In 1993,inEurope, ISO started the SPICE initiative. Both these models define capability levels for software processes and corresponding key process areas. Not every organization that has attempted model based process improvement has succeeded. A group of problems were observed to be general and related to the management of change and to underestimated costs and timeframes. Survey results also included evidence that SPI efforts were overcome by crisis due political struggles within the organizations. Software processes are characterized by a vast number off actors, that is, business goals, organizational culture, accumulated knowledge and experience, company size, the market, domain and environmental and regulatory constraints, etc. SPI is thus challenged by this process diversity, and there is no generic reference model that suits all software development projects and organizations. Furthermore, our analysis showed that the main are as of future research should focus on SPI for small organizations and agile development, measurement, and using SPC and automation/tools.
  • ItemOpen Access
    Innovation in the breeding of common bean through a combined approach of in vitro regeneration and machine learning algorithms
    (Frontiers Media S.A., 2022-08-24) Aasim, Muhammad; Katirci, Ramazan; Baloch, Faheem Shehzad; Mustafa, Zemran; Bakhsh, Allahv; Nadeem, Muhammad Azhar; Ali, Seyid Amjad; Hatipoğlu, Rüştü; Çiftçi, Vahdettin; Habyarimana, Ephrem; Karaköy, Tolga; Chung, Yong Suk; Ali, Seyid Amjad
    Common bean is considered a recalcitrant crop for in vitro regeneration and needs a repeatable and efficient in vitro regeneration protocol for its improvement through biotechnological approaches. In this study, the establishment of efficient and reproducible in vitro regeneration followed by predicting and optimizing through machine learning (ML) models, such as artificial neural network algorithms, was performed. Mature embryos of common bean were pretreated with 5, 10, and 20 mg/L benzylaminopurine (BAP) for 20 days followed by isolation of plumular apice for in vitro regeneration and cultured on a post-treatment medium containing 0.25, 0.50, 1.0, and 1.50 mg/L BAP for 8 weeks. Plumular apice explants pretreated with 20 mg/L BAP exerted a negative impact and resulted in minimum shoot regeneration frequency and shoot count, but produced longer shoots. All output variables (shoot regeneration frequency, shoot counts, and shoot length) increased significantly with the enhancement of BAP concentration in the post-treatment medium. Interaction of the pretreatment × post-treatment medium revealed the need for a specific combination for inducing a high shoot regeneration frequency. Higher shoot count and shoot length were achieved from the interaction of 5 mg/L BAP × 1.00 mg/L BAP followed by 10 mg/L BAP × 1.50 mg/L BAP and 20 mg/L BAP × 1.50 mg/L BAP. The evaluation of data through ML models revealed that R2 values ranged from 0.32 to 0.58 (regeneration), 0.01 to 0.22 (shoot counts), and 0.18 to 0.48 (shoot length). On the other hand, the mean squared error values ranged from 0.0596 to 0.0965 for shoot regeneration, 0.0327 to 0.0412 for shoot count, and 0.0258 to 0.0404 for shoot length from all ML models. Among the utilized models, the multilayer perceptron model provided a better prediction and optimization for all output variables, compared to other models. The achieved results can be employed for the prediction and optimization of plant tissue culture protocols used for biotechnological approaches in a breeding program of common beans. Copyright © 2022 Aasim, Katirci, Baloch, Mustafa, Bakhsh, Nadeem, Ali, Hatipoğlu, Çiftçi, Habyarimana, Karaköy and Chung.
  • ItemOpen Access
    Classroom management in higher education: a systematic literature review
    (Routledge, 2022-02-17) Ateşkan, Armağan; Albayrak, Duygu; Ateşkan, Armağan; Albayrak, Duygu
    This paper presents the findings of a systematic literature review (performed from 2010 to 2020) about classroom management (CM) in higher education. The purpose of this article is to present the state of CM in higher education. Search terms identified 129 papers, from which 42 relevant articles met the inclusion criteria of the current review. Data extraction was initially conducted based on title, keywords, and abstract; it continued with a full-text analysis for the final set of 42 included studies. Based on the reviewed articles factors affecting CM are classified according to students, instructors, and the system. The results show that novice instructors need training about CM and instructors should integrate active learning strategies for better CM. The results also point to a need for researches in online CM. Finally, the findings provide suggestions for future research on CM in higher education.
  • ItemOpen Access
    A phenomenological analysis of primary school teachers’ lived distance education experience during the COVID-19 pandemic in Turkey
    (Routledge, 2022-09-19) Ugur-Erdogmus, F.; Albayrak, Duygu; Albayrak, Duygu
    The purpose of this phenomenological study was to investigate lived distance education (DE) experiences of primary school teachers and their perceptions about DE during the COVID-19 pandemic in Turkey. Twenty primary school teachers who actively taught online participated in online interviews. Phenomenological analysis of the interviews sought to reveal (1) the primary school teachers’ lived DE experience, and (2) their perceptions about DE during the pandemic. The current status of DE, effects of DE, and teachers’ perceptions of DE were the themes revealed. Results showed that teaching practice, interactivity, difficulties, needs, and inequality were the main issues revealed from the primary school teachers’ lived experience. The results also identified the perceived effects of DE on both teachers and students. According to their online experiences, the teachers’ perceptions about DE and their future plans with respect to online teaching were reported.
  • ItemOpen Access
    Light-emitting diodes induced in vitro regeneration of Alternanthera reineckii mini and validation via machine learning algorithms
    (Springer, 2022-10-22) Aasim, M.; Ali, Seyid Amjad; Ali, Seyid Amjad
    Optimization of in vitro regeneration protocol using multiple input variables is highly significant, and can be achieved by validating the data using machine learning algorithms. Shoot tip and nodal segment explants of Alternanthera reineckii mini were inoculated on Murashige and Skoog (MS) medium enriched with different concentrations of benzylaminopurine (BAP), and cultured under five different monochromic light-emitting diodes (LEDs). The attained results were validated through the application of four different supervised machine learning models (RF, XGBoost, KNN, and GP). The prediction of the data were validated by using regression coefficient (R2), mean squared error (MSE), and mean absolute percentage error (MAPE) performance metrics. Results revealed R2 values of 0.61 and 0.59 for shoot counts and shoot length, respectively. The results of MSE were registered between 3.48–5.42 for shoot count and 0.40–0.74 for shoot length, whereas, 28.9–35.1% and 13.2–18.4% MAPE values were recorded for both shoot count and shoot length. Among the utilized models, the RF model validated and predicted the results more accurately, followed by the XGBoost model for both output variables. The results confirm that ML models can be used for data validation, and opens a new era of employing ML modeling in plant tissue culture of other economically important plants. Graphical abstract: Schematic structure presenting input features and outputs together with ML models, used validation and performance metrics [Figure not available: see fulltext.]. © 2022, The Society for In Vitro Biology.
  • ItemOpen Access
    Divide-and-conquer: A systematic approach for subcontractor selection in defense industry projects
    (International Journal of Industrial Engineering, 2022) Şehitoğlu, Anıl; Chouseinoglou, Oumout; Chouseinoglou, Oumout
    Defense industry projects generally are of large size and may be broken down into subparts of different granularity levels, where each subpart may be assigned to a different subcontractor. On the other hand, the problem of subcontractor selection to each subpart is a complex decision-making problem that requires evaluating a number of criteria and the characteristics of each subpart. This study aims to model the problem of subcontractor selection in a defense industry project decomposed to multiple subprojects by combining the Analytic Hierarchy Process (AHP) and Integer Linear Programming (ILP). A project carried out at a defense industry company in Turkey has been used as a case study. An extensive set of criteria specific to the defense industry have been identified, and AHP has been applied to the relevant criteria and alternative subcontractors for each subpart. Finally, ILP has been used to include a set of constraints regarding the project specifications.
  • ItemOpen Access
    Machine learning and artificial neural networks-based approach to model and optimize ethyl methanesulfonate and sodium azide induced in vitro regeneration and morphogenic traits of water hyssops (Bacopa monnieri L.)
    (2022-09-10) Mirza, K.; Aasim, M.; Katırcı, R.; Karataş, M.; Ali, Seyid Amjad; Ali, Seyid Amjad
    Application of chemical mutagens is used for artificially induced in vitro mutation to develop new cultivars with elite characteristics. However, the optimization of selecting proper mutagen, its concentration, and exposure time is of utmost importance, especially for plants containing noteworthy secondary metabolites. In this study, the effect of sodium azide (NaN3) and ethyl methanesulfonate (EMS) in different concentrations (0.025, 0.05, 0.1, and 0.2 mg l−1), and treatment time (30, 60, and 120 min) was investigated on Bacopa monnieri; an important medicinal plant. The maximum shoot counts (57.0) were achieved from the combination of 0.10 mg l−1 EMS × 60 min. Whereas, maximum shoot length (4.07 cm), node numbers (4.97) and leaf numbers (12,23) were achieved from the combination of 0.20 mg l−1 EMS × 120 min, respectively. Combination of 0.025 mg l−1 NaN3 × 120 mg/l yielded maximum shoot counts (52.30), shoot length (3.23 cm), node numbers (6.07) and leaf numbers (12.13). The trained model to predict the outputs were designed and calibrated with machine learning (ML) algorithms. Support Vector Classifier (SVC), Gaussian Process (GP), Extreme Gradient Boosting (XGBoost), Random Forest (RF) models, and Multilayer Perceptron (MLP) neural network algorithms were used to discover the best models and their hyperparameters. The RF model gave exceptional results in the prediction of the outputs. F1 scores of the RF were acquired in the range of 0.98–1.00 for different outputs. The other models’ F1 scores varied in the range of 0.65 and 0.85. The present work opens the new era of applying ML and artificial neural network (ANN) models in plant tissue culture with the possibility of application for other economic crops.
  • ItemOpen Access
    Achieving aging well through senior entrepreneurship: a three-country empirical study
    (Springer New York LLC, 2021-11-12) Zhu, Y.; Collins, Ayşe; Sardana, D.; Çavuşgil, S. T.; Collins, Ayşe
    Seniors strive to achieve aging well by engaging in entrepreneurial activities subsequent to ceasing their organizational employment. While this is a common practice in many societies, scant research exists on what motivates seniors to engage in entrepreneurial activities once they end their formal employment. We adopt the self-determination theory (SDT) to investigate the effects of goal contents and motives on the well-being among seniors who launch their entrepreneurship journeys. Based on in-depth interviews with senior entrepreneurs in China, India, and Turkey, we contribute to extant knowledge by linking separate paradigms. These are as follows: goal contents and intrinsic motivation-driven entrepreneurship, management of inner and outer challenges, and achievement of the eventual outcome of aging well. We also investigate the culture-specific drivers of senior entrepreneurship in a comparative framework.
  • ItemOpen Access
    Exploiting linearity of modular multiplication
    (Springer, 2020) Yıldırım, Hamdi Murat; Yıldırım, Hamdi Murat
    The XOR Open image in new window and the addition ⊞⊞ operations have been widely used as building blocks for many cryptographic primitives. These operations and the multiplication ⊙⊙ operation are successively used in the design of IDEA and the MESH block ciphers. This work presents several interesting algebraic properties of the multiplication operation. By fixing one operand, we obtain vector valued function ggZggZ on Zn2Z2n, associated with ⊙⊙. In this paper we show that the nonlinearity of ggZggZ remains the same under some transformations of Z and moreover we give an upper bound for the nonlinearity of ggZggZ when Z is a power of 2. Under weak-key assumptions, we furthermore present a list of new linear relations for 1-round IDEA cipher, some of directly derived and others algorithmically generated using these relations and known ones. We extend the largest linear weak key class for IDEA cipher with size 223223 to derive such a class with sizes 224224. Under the independent key subblocks (subkeys) and weak-key assumptions we derive many linear relations for IDEA cipher using linear relations for 1-round IDEA cipher.
  • ItemOpen Access
    Preservice teachers' Facebook usage and their perspectives about Facebook as a professional development tool
    (Ahi Evran Üniversitesi Kırşehir Eğitim Fakültesi, 2011) Köşkeroğlu-Büyükimdat, M.; Albayrak, Duygu; Uğur-Erdoğmuş, F.; Yıldırım, S.; Eryol, G.; Ataman, Y. E.; Albayrak, Duygu
    In this study, an explanatory mixed method design was employed to evaluate preservice information technology teachers’ Facebook usage and their perspectives about Facebook as a professional development tool. In quantitative phase, data were collected through a Facebook usage survey on a total number of 338 undergraduate Computer Education and Instructional Technology (CEIT) students from three representative state universities in Turkey. Survey results indicated that preservice teachers favored and utilized Facebook. To find out more in-depth data, the results of quantitative data analysis were used to develop a structured interview to be done with four preservice teachers who were selected purposefully. The data collected from the interviews were subjected to content analysis where coding was conducted to create meaningful organization of the data. According the results of this explanatory study especially communication, sharing and socializing capacity of Facebook were found important in terms of using Facebook as a professional development tool.
  • ItemOpen Access
    3. yılında Türkiye'nin internetle savaşı: Donkişot, Devekuşu,Harakiri
    (Türk Kütüphaneciler Derneği, 2010) Akgül, Mustafa; Akgül, Mustafa
    Türkiye'de İnternet yasaklarını düzenleyen 5651 numaralı kanun çıkalı 3 yılı aştı. Bu kanunun çıkış sürecinde ve bugüne kadar uygulamasında, ülkemiz bir yandan dünyaya önderlik etmeye çalıştı, bir yandan Youtube/ Google gibi devlere meydan okudu; onlara büyük vergi cezaları kesti. Ülkemiz, kendi internet algılaması ve değerlendirmesini dünyaya empoze etmeye çalışıyor. Böylece, bu konuda, uluslararası hukuku tesis etmeye çalışıyor. Bunu, uluslararası forumlarda, Birleşmiş Milletlerde önererek, savunarak, müzakere ederek yapmıyor. İnterneti, basın gibi algılayarak, basına uygulanan yasaklama alışkanlıkları ile yasaklıyor. Başbakan dahil internet yasaklarını önemli bir çoğunluk deliyor. Bu yasaklara Cumhurbaşkanı, Avrupa Birliği’nden sorumlu Devlet Bakanı, hatta Ulaştırma Bakanı ve BTK (Bilgi Teknolojileri ve İletişim Kurumu) Başkanı da karşı beyanlar veriyor. Bu arada Hukuk'un temel ilkeleri, kuvvetler ayrılığı, adil yargılama, özgürlüklerin özüne dokunulmaz ilkesi gözardı ediliyor. Bir başka deyişle, ülkenin hukukçuları ve düşünen insanların gözü önünde bir Hukuk Faciası yaşanıyor. Ve ülkemiz, matbaada olduğu gibi, interneti anlamayarak, harakiri yapıyor.Bu yazıda, Türkiye'nin internetle savaşının 3 yıllık macerasının boyutları değerlendirecektir.
  • ItemOpen Access
    Average distance estimation in randomly deployed wireless sensor networks (WSNs): an analytical study
    (Inderscience Enterprises, 2019) Sevgi, Cüneyt; Sevgi, Cüneyt
    A wireless sensor network (WSN) is an energy-scarce network in which the energy is primarily dissipated by the nodes during data transmission to the base station (BS). The location of the BS dramatically affects the energy dissipation, the throughput, and the lifetime. While in certain studies the optimal positioning of a BS is considered, the system parameters are optimized when the BS location is known in advance in many others. Herein, we provide a general-purpose mathematical framework to find the expected distance value between every point within any n-sided simple polygon shaped sensing field and an arbitrarily located BS. Knowing this value is imperative particularly in random deployment as it is used for energy-efficient clustering. Although similar derivations appear in the related literature, to the best of our knowledge, this study departs from them, since our derivations do not depend on the shape of the field and the orientation of BS relative to it.
  • ItemOpen Access
    Structural equation modeling in cloud computing studies: a systematic literature review
    (Emerald, 2019) Pişirir, E.; Uçar, Erkan; Chouseinoglou, O.; Sevgi, Cüneyt; Uçar, Erkan; Sevgi, Cüneyt
    Purpose – This study aims to examine the current state of literature on structural equation modeling (SEM) studies in “cloud computing” domain with respect to study domains of research studies, theories and frameworks they use and SEM models they design. Design/methodology/approach – Systematic literature review (SLR) protocol is followed. In total, 96 cloud computing studies from 2009 to June 2018 that used SEM obtained from four databases are selected, and relevant data are extracted to answer the research questions. Findings – A trend of increasing SEM usage over years in cloud studies is observed, where technology adoption studies are found to be more common than the use studies. Articles appear under four main domains, namely, business, personal use, education and health care. Technology acceptance model (TAM) is found to be the most commonly used theory. Adoption, intention to use and actual usage are the most common selections for dependent variables in SEM models, whereas security and privacy concerns, costs, ease of use, risks and usefulness are the most common selections for causal factors. Originality/value – Previous cloud computing SLR studies did not focus on statistical analysis method used in primary studies. This review will display the current state of SEM studies in cloud domain for all future academics and practical professionals.
  • ItemOpen Access
    Cloud-based test tools: A brief comparative view
    (Sciendo, 2018) Kilinç, N.; Sezer, L.; Mishra, A.
    The concept of virtualization has brought life to the new methods of software testing. With the help of cloud technology, testing has become much more popular because of the opportunities it provides. Cloud technologies provides everything as a service, hence the software testing is also provided as a service on cloud with the privileges of lower cost of testing, and relatively less effort. There are various cloud-based test tools focusing on different aspects of software testing such as load tests, regression tests, stress tests, performance tests, scalability tests, security tests, functional tests, browser performance tests, and latency tests. This paper investigates the cloud-based testing tools focusing on different aspects of software testing.
  • ItemOpen Access
    Fair task allocation in crowdsourced delivery
    (Institute of Electrical and Electronics Engineers, 2018) Basik, F.; Gedik, B.; Ferhatosmanoglu, H.; Wu, K.
    Faster and more cost-efficient, crowdsourced delivery is needed to meet the growing customer demands of many industries. In this work, we introduce a new crowdsourced delivery platform that takes fairness towards workers into consideration, while maximizing the task completion ratio. Since redundant assignments are not possible in delivery tasks, we first introduce a 2-phase assignment model that increases the reliability of a worker to complete a given task. To realize the effectiveness of our model in practice, we present both offline and online versions of our proposed algorithm called F-Aware. Given a task-to-worker bipartite graph, F-Aware assigns each task to a worker that maximizes fairness, while allocating tasks to use worker capacities as much as possible. We present an evaluation of our algorithms with respect to running time, task completion ratio, as well as fairness and assignment ratio. Experiments show that F-Aware runs around $10^7\times$ faster than the TAR-optimal solution and assigns 96.9% of the tasks that can be assigned by it. Moreover, it is shown that, F-Aware is able to provide a much fair distribution of tasks to workers than the best competitor algorithm. IEEE
  • ItemOpen Access
    Task allocation onto a hypercube by recursive mincut bipartitioning
    (Elsevier, 1990) Ercal, F.; Ramanujam, J.; Sadayappan, P.
    An efficient recursive task allocation scheme, based on the Kernighan-Lin mincut bisection heuristic, is proposed for the effective mapping of tasks of a parallel program onto a hypercube parallel computer. It is evaluated by comparison with an adaptive, scaled simulated annealing method. The recursive allocation scheme is shown to be effective on a number of large test task graphs-its solution quality is nearly as good as that produced by simulated annealing, and its computation time is several orders of magnitude less
  • ItemOpen Access
    Using social networking sites for teaching and learning: students’ involvement in and acceptance of Facebook as a course management system
    (Sage, 2015) Albayrak, D.; Yildirim, Z.
    This study investigates students’ involvement in Facebook as a course management system (CMS), Facebook acceptance, and the relationships between the two. The study used Facebook as a CMS in two freshman courses and employed mixed method as part of an action-research approach. Forty-two students participated in the study, and 12 of those students were selected for face-to-face interviews through maximum variation sampling. Quantitative data were collected through questionnaires and course Facebook page logs. Qualitative data were collected through the interviews. The quantitative data analysis consisted of descriptive statistics and correlation analyses. The findings indicate that the relationships between course Facebook page involvement and Facebook acceptance differed according to the course. The findings support that Facebook as a CMS has the potential to increase student involvement in discussions and out-of-class communication among instructors and students.
  • ItemOpen Access
    Investigation of individual factors impacting the effectiveness of requirements inspections: a replicated experiment
    (Springer, 2014-02) Albayrak, Ö.; Carver, J. C.
    This paper presents a replication of an empirical study regarding the impact of individual factors on the effectiveness of requirements inspections. Experimental replications are important for verifying results and investigating the generality of empirical studies. We utilized the lab package and procedures from the original study, with some changes and additions, to conduct the replication with 69 professional developers in three different companies in Turkey. In general the results of the replication were consistent with those of the original study. The main result from the original study, which is supported in the replication, was that inspectors whose degree is in a field related to software engineering are less effective during a requirements inspection than inspectors whose degrees are in other fields. In addition, we found that Company, Experience, and English Proficiency impacted inspection effectiveness.
  • ItemOpen Access
    Harbours of crisis and consent: the technopolitics of coastal infrastructure in colonial Cyprus, 1895-1908
    (SAGE Publications, 2016-09) Karas, S.; Arapostathis, S.
    By the late 1800s British colonial rule in Cyprus was experiencing both a socioeconomic and a legitimacy crisis. Britain's development projects were intended to quell the crisis and consolidate colonial authority. Famagusta Harbour construction was an integral part of that programme, but it antagonised wealthy and influential Cypriots in Larnaca. They believed that such infrastructure would undermine the importance of Larnaca harbour and threaten their commercial and political interests. Their protests threatened the colonial administration with a new crisis that was averted by the integration of Larnaca's Harbour into British plans. The colonial regime had to negotiate and co-operate with local networks of power in order to realise its development programme: harbour development was no mere rational engineering exercise.
  • ItemOpen Access
    Workload clustering for increasing energy savings on embedded MPSOCS
    (John Wiley and Sons, 2012) Ozturk, O.; Kandemir, M.; Narayanan, S. H. K.
    Voltage/frequency scaling andprocessor low-power modes (i.e., processor shut-down) are two important mechanisms usedfor reducing energy consumption in embedded MPSoCs. While a unified scheme that combines these two mechanisms can achieve significant savings in some cases, such an approach is limited by the code parallelization strategy employed. In this paper, we propose a novel, integer linear programming (ILP) based workload clustering strategy across parallel processors, oriented towards maximizing the number of idle processors without impacting original execution times. These idle processors can then be switched to a low power mode to maximize energy savings, whereas the remaining ones can make use ofvoltage/frequency scaling. In order to check whether this approach brings any energy benefits over the pure voltage scaling based, pure processor shut-down based, or a simple unified scheme, we implemented four different approaches and tested them using a set of eight array/loop-intensive embedded applications. Our simulation-based analysis reveals that the proposed ILP based approach (1) is very effective in reducing the energy consumptions of the applications tested and (2) generates much better energy savings than all the alternate schemes tested (including a unified scheme that combines voltage/frequency scaling and processor shutdown).