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Article Citation - Scopus: 6Predictive Models for Treated Clayey Soils Using Waste Powdered Glass and Expanded Polystyrene Beads Using Regression Analysis and Artificial Neural Network(Springer Science and Business Media Deutschland GmbH, 2024) Akis,E.; Akış, Ebru; Cigdem,O.Y.; Akış, Ebru; Civil Engineering; Civil EngineeringWaste materials contribute to a wide range of environmental and economic problems. To minimize their effects, a safe strategy for reducing such negative impact is required. Recycling and reusing waste materials have proved to be effective measures in this respect. In this study, an eco-friendly treatment is investigated based on using waste powdered glass (WGP) and EPS beads (EPSb) as mechanical and chemical admixers in soils. For this purpose, Atterberg limit, standard proctor, free swell, and unconfined compression tests are performed on soil samples with different ratios of waste materials at their optimum moisture contents. The obtained test results indicate that adding WGP to cohesive soils increases the unconfined compressive strength (UCS) and reduces free swell (FS). In contrast, using EPSb reduces both FS and UCS of the treated soil samples. An optimum combination of both waste materials is determined for the improvement of the properties of high plasticity clay used in this study. Furthermore, multiple linear regression (MLR) and artificial neural network (ANN) methods are used to predict the FS and UCS of the clayey soils based on the data obtained here and the experimental test results reported in the literature. Once the FS and UCS values of untreated soil and additive percentages are defined as independent variables, both methods are shown to predict the FS and UCS values of the treated soil samples on a satisfactory level with the coefficient of correlation (R2) values greater than 0.926. Additionally, when only the index properties (liquid limit, plastic limit, and plasticity index) of the soil samples with waste materials are used as dependent variables, the R2 values obtained by the ANN method are 0.968 and 0.974 for FS and UCS, respectively. The results of the untreated soil samples' FS and UCS tests are known, and the linear regression and ANN techniques yield similar results. Lastly, the ANN method is used to predict the FS and UCS of the treated samples in accordance to the limited predictors (e.g., only the Atterberg limits of the soil sample). © The Author(s) 2024.Article Citation - WoS: 2Citation - Scopus: 4Optimum Cost Prediction of Reinforced Concrete Cantilever Retaining Walls(Mdpi, 2023) Akis, EbruReinforced concrete cantilever retaining walls (RCCRWs) are widely used in civil engineering projects as a common type of retaining structure. The design of these structures focuses on ensuring safety against various failure scenarios and compliance with standard building code requirements. This research aims to enhance the design process of RCCRWs by developing a specific code and optimizing it through a metaheuristic-based algorithm. In this study, the cost prediction of RCCRWs is also investigated through a parametric study involving key variables such as wall height, seismic zone, backfill material properties, and backfill inclination angle. To achieve this, non-linear regression analysis is employed to establish an empirical correlation, enabling cost estimation for optimized RCCRWs. The resulting prediction equation is simple to use, requiring only limited inputs. Therefore, it can be applied during the initial stages of a project, making a valuable contribution in determining approximate costs for RCCRW projects.Article Citation - WoS: 5Citation - Scopus: 5Improvement of Electrical Characteristics of Snse/Si Heterostructure by Integration of Si Nanowires(Elsevier, 2021) Coskun, E.; Gullu, H. H.; Emir, C.; Parlak, M.In this study, the effects of the nanowire geometry on Si wafer substrate were investigated for the SnSe/Si-nanowire heterojunction device and the obtained results were compared with the one fabricated on planar Si surface. Nanowires on Si surface were produced by metal-assisted etching method and the SnSe film layer was deposited by thermal evaporation technique. On both Si and glass surfaces, deposited film shows polycrystalline and single SnSe phase. From optical transmission measurements, optical band gap of this film was determined as 1.36 eV in a good agreement with the literature. All SnSe/Si heterostructures were found in a p-n diode behavior and the ideality factor and series resistance values were calculated as 2.40, 547 Omega, and 3.71, 1.57 x 10(3) Omega, for SnSe/Si-nanowire and SnSe/Si heterojunctions, respectively. As a result, an improvement in device characteristics concerning the planar Si structure was found by utilizing Si nanowire structure.Article Citation - WoS: 12Citation - Scopus: 19An Ontology-Based Multi-Agent Virtual Enterprise System (omave): Part 1: Domain Modelling and Rule Management(Taylor & Francis Ltd, 2017) Sadigh, Bahram Lotfi; Unver, Hakki Ozgur; Nikghadam, Shahrzad; Dogdu, Erdogan; Ozbayoglu, A. Murat; Kilic, S. EnginNew advancements in computers and information technologies have yielded novel ideas to create more effective virtual collaboration platforms for multiple enterprises. Virtual enterprise (VE) is a collaboration model between multiple independent business partners in a value chain and is particularly suited to small and medium-sized enterprises (SMEs). The most challenging problem in implementing VE systems is ineffcient and inFLexible data storage and management techniques for VE systems. In this research, an ontology-based multi-agent virtual enterprise (OMAVE) system is proposed to help SMEs shift from the classical trend of manufacturing part pieces to producing high-value-added, high-tech, innovative products. OMAVE targets improvement in the FLexibility of VE business processes in order to enhance integration with available enterprise resource planning (ERP) systems. The architecture of OMAVE supports the requisite FLexibility and enhances the reusability of the data and knowledge created in a VE system. In this article, a detailed description of system features along with the rule-based reasoning and decision support capabilities of OMAVE system are presented. To test and verify the functionality and operation of this system, a sample product was manufactured using OMAVE applications and tools with the contribution of three SMEs.Article Citation - WoS: 10Citation - Scopus: 15Increasing Innovative Working Behaviour of Information Technology Employees in Vietnam by Knowledge Management Approach(Mdpi, 2020) Quoc Trung Pham; Anh-Vu Pham-Nguyen; Misra, Sanjay; Damasevicius, Robertas; Pham-nguyen, Anh-vu; Pham, Quoc TrungToday, Knowledge Management (KM) is becoming a popular approach for improving organizational innovation, but whether encouraging knowledge sharing will lead to a better innovative working behaviour of employees is still a question. This study aims to identify the factors of KM affecting the innovative working behaviour of Information Technology (IT) employees in Vietnam. The research model involves three elements: attitude, subjective norm and perceived behavioural control affecting knowledge sharing, and then, on innovative working behaviour. The research method is the quantitative method. The survey was conducted with 202 samples via the five-scale questionnaire. The analysis results show that knowledge sharing has a positive impact on the innovative working behaviour of IT employees in Vietnam. Besides, attitude and perceived behavioural control are confirmed to have a strong positive effect on knowledge sharing, but the subjective norm has no significant impact on knowledge sharing. Based on this result, recommendations to promote knowledge sharing and the innovative work behaviour of IT employees in Vietnam are made.Article Citation - WoS: 7Citation - Scopus: 7Temperature dependent bandgap in NaBi(WO4)2 single crystals(Elsevier Gmbh, 2022) Isik, M.; Gasanly, N. M.; Darvishov, N. H.; Bagiev, V. E.The double tungstates have been an attractive research interest due to their optoelectronic applications. In the present work, NaBi(WO4)(2), one of the members of double tungstates family, was grown by Czochralski method as single crystal form and optically investigated. X-ray diffraction pattern presented three peaks associated with tetragonal scheelite crystalline structure. Optical properties of the crystal were studied by performing temperature-dependent transmission measurements between 10 and 300 K. The shift of the absorption edge to higher energies was observed with decrease of temperature. The analyses indicated that direct band gap energy increases from 3.50 to 3.60 eV when the temperature was decreased from room temperature to 10 K. The temperature dependency of bandgap was studied considering the Varshni model and fitting of the experimental data under the light of model presented the optical parameters of band gap energy at 0 K, rate of band gap change with temperature and Debye temperature as E-g(0) = 3.61 eV, gamma = 8.83 x 10(-4) eV/K and beta = 456 K, respectively. Urbach energies were also determined from the analyses as 122 and 113 meV for 10 and 300 K experimental data, respectively.Review The Hesitant Hand: Taming Self-Interest in the History of Economic Ideas.(Routledge Journals, Taylor & Francis Ltd, 2014) Temel, Bulent[No Abstract Available]Article Citation - WoS: 33Citation - Scopus: 56Smart irrigation system for environmental sustainability in Africa: An Internet of Everything (IoE) approach(Amer inst Mathematical Sciences-aims, 2019) Adenugba, Favour; Misra, Sanjay; Maskeliunas, Rytis; Damasevicius, Robertas; Kazanavicius, EgidijusWater and food are two of the most important commodities in the world, which makes agriculture crucial to mankind as it utilizes water (irrigation) to provide us with food. Climate change and a rapid increase in population have put a lot of pressure on agriculture which has a snowball effect on the earth's water resource, which has been proven to be crucial for sustainable development. The need to do away with fossil fuel in powering irrigation systems cannot be over emphasized due to climate change. Smart Irrigation systems powered by renewable energy sources (RES) have been proven to substantially improve crop yield and the profitability of agriculture. Here we show how the control and monitoring of a solar powered smart irrigation system can be achieved using sensors and environmental data from an Internet of Everything (IoE). The collected data is used to predict environment conditions using the Radial Basis Function Network (RBFN). The predicted values of water level, weather forecast, humidity, temperature and irrigation data are used to control the irrigation system. A web platform was developed for monitoring and controlling the system remotely.Article Citation - WoS: 6Citation - Scopus: 6Multiple Sclerosis Experiences of Couples: Examination of Patient and Partner Perspectives(Sage Publications Ltd, 2022) Demirtepe-Saygili, DilekThe study aims to investigate Multiple Sclerosis (MS) experiences of couples. Using a dyadic qualitative method, separate simultaneous interviews were conducted with 20 couples, including one partner with MS. The themes resulting from content analysis were examined in two categories: Convergent (anxiety about future, acceptance of MS and MS as an accelerator of the relationship) and divergent (sexual problems, the experience of MS symptoms, the priority of the problems and untold issues). The findings revealed shared and unique perspectives of partners in the illness process, having the potential to guide the psychosocial interventions for couples living with a chronic illness.Article Citation - WoS: 1Citation - Scopus: 1Ongoing Discussion: Is Prophylactic Central Neck Dissection Necessary in Ct1a-B,2n0 Papillary Thyroid Cancer(Sage Publications Ltd, 2025) Bayir, Omer; Akan, Latif; Kizilgul, Muhammed; Ucan, Bekir; Karahan, Sevilay; Toptas, Gokhan; Korkmaz, Mehmet HakanObjective: To analyze the central lymph node metastasis (CLNM) rates of patients who underwent prophylactic central lymph node dissection (pCLND) with total thyroidectomy for cT1-2N0 papillary thyroid cancer in our clinic, to evaluate the conditions associated with lymph node metastasis, and to examine the necessity of pCLND in these patient groups.Methods: This study includes a retrospective review of the medical data of patients who underwent bilateral/unilateral central lymph node dissection (CLND) (b/uCLND) with total thyroidectomy in our center between 2013 and 2021, whose fine needle aspiration biopsy result was reported as malignant, who were detected as cT1a-1b-2N0 on thyroid and neck ultrasonography.Results: Of the 251 patients included in the study, 63 (25%) had CLNM (49 (19.5%) ipsilateral and 14 (5.5%) had contralateral CLNM). Twenty-two (20.1%) of 109 patients with cT1a, 30 (28.3%) of 106 patients with cT1b, and 11 (30.5%) of 36 patients with cT2 had CLNM, and metastasis rates increased with increasing cT category. CLNM rates increased with increasing pT category (p=0.005). CLNM was present in 21 (38.8%) of 54 patients (21.5%) with collision tumors, and metastasis rates increased significantly compared to the presence of a single histopathologic tumor (p=0.006). CLNM rates were higher in patients with multicentric tumor localization than in those with unicentric localization (p=0.006).Conclusion: Multicentricity, bilaterality, capsule invasion, collision tumors and tumors larger than 1 cm increase the risk of CLNM. uCLND for tumors larger than 1 cm, bCLND for tumors larger than 2 cm can be considered. We believe that patients with unilateral CLNM also have an increased risk of contralateral metastasis.
