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Article Citation - WoS: 3Citation - Scopus: 3On the Fixed Points of Iterative Contractive Mappings Defined Via Implicit Relation(Taylor & Francis Ltd, 2021) Aksoy, Umit; Erhan, Inci M.; Fulga, Andreea; Karapinar, ErdalIn this paper, we consider an implicit relation to generalize iterative fixed point results in the literature in the context of metric spaces. We conclude that several existing results are immediate consequences of our main results.Article Citation - WoS: 8Citation - Scopus: 15Identification of Linear Handling Models for Road Vehicles(Taylor & Francis Ltd, 2008) Arikan, K. B.; Unlusoy, Y. S.; Korkmaz, I.; Celebi, A. O.This study reports the identification of linear handling models for road vehicles starting from structural identifiability analysis, continuing with the experiments to acquire data on a vehicle equipped with a sensor set and data acquisition system, and ending with the estimation of parameters using the collected data. The model structure originates from the well-known linear bicycle model that is frequently used in handling analysis of road vehicles. Physical parameters of the bicycle model structure are selected as the unknown parameter set that is to be identified. Global identifiability of the model structure is analysed, in detail, and concluded according to various available sensor sets. Physical parameters of the bicycle model structure are estimated using prediction error estimation method. Genetic algorithms are used in the optimisation phase of the identification algorithm to overcome the difficulty in the selection of initial values for parameter estimates. Validation analysis of the identified model is also presented. The identified model is shown to track the system response successfully.Article On the Injectivity With Respect To q of the Lupas q-transform(Taylor & Francis Ltd, 2024) Yilmaz, Ovgue Gurel; Ostrovska, Sofiya; Turan, MehmetThe Lupas q-transform has first appeared in the study of the Lupas q-analogue of the Bernstein operator. Given 0 < q < 1 and f is an element of C[0, 1], the Lupas q-transform is defined by Lambda(q)(f; x) Pi(infinity)(k=0) 1/1 + q(k)x Sigma(k=0)f(1 - q(k))q(k(k-1)/2)x(k)/(1 - q)(1 - q(2)) center dot center dot center dot (1 - q(k)), x >= 0. During the last decades, this transform has been investigated from a variety of angles, including its analytical, geometric features, and properties of its block functions along with their sums. As opposed to the available studies dealing with a fixed value of q, the present work is focused on the injectivity of Lambda(q) with respect to parameter q. More precisely, the conditions on f such that equality Lambda(q)(f; x) = Lambda(r)(f; x); x >= 0 implies q = r have been established.Article Citation - WoS: 8Citation - Scopus: 10Biomechanical Effects of Two Different Collar Implant Structures on Stress Distribution Under Cantilever Fixed Partial Dentures(Taylor & Francis Ltd, 2011) Meric, Gokce; Erkmen, Erkan; Kurt, Ahmet; Eser, Atilim; Ozden, Ahmet UtkuObjective. The purpose of the study was to compare the effects of two distinct collar geometries of implants on stress distribution in the bone around the implants supporting cantilever fixed partial dentures (CFPDs) as well as in the implant-abutment complex and superstructures. Materials and methods. The three-dimensional finite element method was selected to evaluate the stress distribution. CFPDs which was supported by microthread collar structured (MCS) and non-microthread collar structured (NMCS) implants was modeled; 300 N vertical, 150 N oblique and 60 N horizontal forces were applied to the models separately. The stress values in the bone, implant-abutment complex and superstructures were calculated. Results. In the MCS model, higher stresses were located in the cortical bone and implant-abutment complex in the case of vertical load while decreased stresses in cortical bone and implant-abutment complex were noted within horizontal and oblique loading. In the case of vertical load, decreased stresses have been noted in cancellous bone and framework. Upon horizontal and oblique loading, a MCS model had higher stress in cancellous bone and framework than the NMCS model. Higher von Mises stresses have been noted in veneering material for NMCS models. Conclusion. It has been concluded that stress distribution in implant-supported CFPDs correlated with the macro design of the implant collar and the direction of applied force.Article Enhancing Machining Efficiency and Sustainability of Ti-6Al-4V Through Minimum Quantity Lubrication With Ester-Based Oils(Taylor & Francis Ltd, 2025) Namlu, Ramazan Hakki; Kavut, Kuebra; Tom, Hanife GulenTi-6Al-4 V is known as difficult-to-cut due to its low thermal conductivity and high chemical reactivity. While cutting fluids aid lubrication and reduce friction, Conventional Cutting Fluids (CCF) have high consumption, limited efficiency gains and negative environmental and health effects. Therefore, there is an ongoing search for more sustainable alternatives to CCF that do not adversely affect machining performance. Minimum Quantity Lubrication (MQL), which delivers compressed air - oil aerosol, has emerged as a promising solution by drastically reducing fluid use and associated risks. Selecting the right MQL fluid is key to optimising machining performance. This study evaluates MQL fluids based on polyol and polymeric esters for Ti-6Al-4 V machining and compares their performance with CCF. Cutting forces, surface roughness and topography are examined. Results show that MQL reduces cutting forces up to 21.7% and surface roughness up to 57.6% compared to CCF, with more uniform surface topography. Among MQL oils, polymeric esters perform better than polyol esters, with a reduction in cutting force up to 14.6% and surface roughness up to 47.7%. High viscosity indexed polymeric esters showed the best overall performance due to their thermal stability. Moreover, according to the sustainability assessment analysis polymeric esters were identified as the most sustainable option.Review A Study of Existing Use Case Extensions and Experience: a Systematic Review(Taylor & Francis Ltd, 2020) Arogundade, Oluwasefunmi'Tale; Olotu, Samuel Ibukun; Abayomi-Alli, Olusola; Misra, Sanjay; Ikotun, Abiodun MotunrayoUse case has embedded potentials that enable the diversity in its adoption to addressing other issues in software engineering. This objective of this paper is to gathered and classified use case researches carried out over the years and defines the state-of-art. We identified and analysed 62 relevant articles with deep insights into six different initiatives. The publications included 29 journal articles, 18 conference articles, 3 reports, 5 book chapters, 5 workshops and 2 symposiums. This study deduced that as many as 15 different extensions are proposed from use case ranging from formal descriptions to subjective methodology. Use case has evolved from initial functional requirement elicitation to a more formal and extensive structure. There are fewer publications in cloud computing and use case-based systems. This study contributed to the use case body of knowledge by assessing the extended initiatives and giving an overview of the challenges that are not yet resolved.Article Citation - WoS: 13Citation - Scopus: 15Behavioural Representation and Simulation of Design Concepts for Systematic Conceptual Design of Mechatronic Systems Using Petri Nets(Taylor & Francis Ltd, 2014) Araz, Macit; Erden, ZuhalThe systematic representation of design concepts is an important requirement for computational support during the conceptual design stage within the process of product development. Behavioural simulation of design concepts is used as a systematic representation framework, and behavioural representation is based on modelling and simulating the behaviour of a design artefact at the conceptual level to perform an overall function, leading to behaviour-based conceptual design. The behaviour-based conceptual design approach is critical for mechatronic systems since they require synergistic integration starting from the initial conceptual design phase. The present study is focused on behavioural representation and simulation of design concepts via discrete event system specification formalism and Petri Nets so as to contribute to systematic conceptual design in mechatronic systems. The paper introduces a representation framework for the behaviour-based conceptual design of mechatronic systems and its implementation on five selected case studies, among laboratory-level educational robots. In addition to Petri Net modelling and computer simulations, the implementation also includes physical simulations of the intended operational behaviours for educational robots on a distributed physical structure called the desktop design model'. In this paper, implementation on one of these case studies, namely the frog robot', is presented in detail.Article A Coupled Modelling and Simulation Approach to Electromagnetic Sheet Metal Forming(Taylor & Francis Ltd, 2025) Aslan, Ozgur; Kabakci, Gamze Cakir; Sait, Ferit; Camalan, Caner; Baranoglu, Besim; Bayraktar, EminThis study presents a coupled numerical and experimental investigation of electromagnetic forming (EMF) for aluminium sheets. A custom simulation framework is developed in ABAQUS/Standard using user-defined material (UMAT) and load (DLOAD) subroutines. The magnetic pressure exerted on the workpiece is computed through a finite difference-based solution of Maxwell's equations and applied to the mechanical solver. The mechanical response of the material is modelled using a strain-rate-sensitive plasticity law calibrated for aluminium 7075-O. Experimental forming trials are performed using a custom-built EMF setup, and the results are compared with numerical predictions to validate the model. The comparison shows strong agreement in deformation profiles, confirming the predictive capability of the proposed simulation strategy. This work offers a reliable computational tool for optimising EMF processes and provides insights into material behaviour under high strain rate electromagnetic loading.Article Distance-Based Estimation Under Progressive Type-I Interval Censoring(Taylor & Francis Ltd, 2026) Balakrishnan, N.; Castilla, E.Monte Carlo simulation is used to demonstrate improved estimation performance of proposed distance-type estimators for lifetime models under progressive Type-I interval censoring. We propose novel distance-based estimators for lifetime models under progressive Type-I interval censoring. These estimators minimize the discrepancy between observed and model-based conditional failure probabilities using either quadratic or Mahalanobis distances, providing natural alternatives to maximum likelihood estimators (MLEs). Through extensive Monte Carlo simulations, we demonstrate that the Mahalanobis estimator outperforms MLE, particularly under heavy censoring or sparse data. The quadratic estimator also yields competitive results, especially under model misspecification. Two real data examples illustrate the practical advantages of the proposed approach.Article Citation - WoS: 19Citation - Scopus: 21A Hybrid Approach for Selecting Material Handling Equipment in a Warehouse(Taylor & Francis Ltd, 2016) Saputro, Thomy Eko; Rouyendegh (Babek Erdebilli), Babak DaneshvarWarehouse operations are closely related to material handling activities. Loading, unloading, transporting and picking material constitute a huge part of the activities. In order to handle material properly as well as to contribute value to the material, the operator and the environment, utilizing Material Handling Equipment (MHE) is required. The selection of proper MHEs requires great focus since its consideration is linked to mutli-criteria and multi-objective decision making problems. Here, a hybrid method is proposed to address the MHE selection problem. An approach that integrates the entropy based hierarchical fuzzy Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) and Multi-Objective Mixed Integer Linear Programming (MOMILP) is used for seeking the best alternative. The evaluation of alternatives is performed based on both subjective and objective criteria. Subjective weights are derived from a fuzzy Analytic Hierarchy Process (AHP). To deal with objective criteria, the entropy method is adopted to determine the weights, and the integrated weights are also calculated. The alternatives are rated by using fuzzy TOPSIS. For final execution of the selection, an MOMILP model is developed incorporating two goals, namely to minimize the disadvantage of material handling operation and to minimize the total cost of material handling. The AUGMented E-CONtraint method (AUGMECON) is used to solve the model. A case study is given to illustrate the method. The results show the effectiveness of the hybrid method in complex decision making.
