Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Access type: Open accessPublisher: search.filters.publisher.Cambridge University Press

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  • Conference Object
    Citation - Scopus: 1
    From Human-Centred To Humanity-Ecosystem Centred Design. How Can We Dialogue With Ai?
    (Cambridge University Press, 2024) Oğrak,Z.; Altıparmakoğulları,Y.
    With the swift entry of artificial intelligence (AI) into everyday life, human-product interactions are becoming increasingly complex. We suggest an ecosystem-minded, humanity-centered design approach to better understand this complexity. Simultaneously with the development of interaction types, discussions and developments on theories of mental models are crucial to understanding and improving the nature of these interactions. In this paper, we address the gap in mental model theories and extend Norman's conceptual model at three dialogue levels: dialogue in language, mind, and use. © 2024 Proceedings of the Design Society. All rights reserved.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 4
    Design of a Novel Hybrid Cable-Constrained Parallel Leg Mechanism for Biped Walking Machines
    (Cambridge University Press, 2023) Demirel, M.; Kiper, G.; Carbone, G.; Ceccarelli, M.
    In this paper, a novel cable-constrained parallel mechanism is presented as a lightweight, low-cost leg mechanism design for walking machines to be used on flat surfaces. The proposed leg mechanism has three translational degrees of freedom. It is based on two specific hybrid kinematic topologies being herewith proposed. The paper reports the kinematic analysis formulation and a position performance evaluation to confirm the main characteristics of the proposed solutions. A 3D CAD model and simulations are carried out to demonstrate the feasibility of the proposed design for performing a human-like gait trajectory. A prototype has been built, and preliminarily tests have been conducted to confirm the motion capabilities of the proposed mechanism design. Then a second, enhanced prototype has been designed and built. An experimental validation is carried out for tracking a planar walking trajectory with the built prototypes by using a real-time PCI controller. Results are presented to validate the operation characteristics of the proposed mechanism and to prove its feasibility for legged walking machines. © The Author(s), 2023.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 6
    Nonlinear Model Identification and Statistical Verification Using Experimental Data With a Case Study of the Ur5 Manipulator Joint Parameters
    (Cambridge University Press, 2022) Abedinifar, Masoud; Ertuğrul, Şeniz; Argüz, Serdar Hakan
    The identification of nonlinear terms existing in the dynamic model of real-world mechanical systems such as robotic manipulators is a challenging modeling problem. The main aim of this research is not only to identify the unknown parameters of the nonlinear terms but also to verify their existence in the model. Generally, if the structure of the model is provided, the parameters of the nonlinear terms can be identified using different numerical approaches or evolutionary algorithms. However, finding a non-zero coefficient does not guarantee the existence of the nonlinear term or vice versa. Therefore, in this study, a meticulous investigation and statistical verification are carried out to ensure the reliability of the identification process. First, the simulation data are generated using the white-box model of a direct current motor that includes some of the nonlinear terms. Second, the particle swarm optimization (PSO) algorithm is applied to identify the unknown parameters of the model among many possible configurations. Then, to evaluate the results of the algorithm, statistical hypothesis and confidence interval tests are implemented. Finally, the reliability of the PSO algorithm is investigated using experimental data acquired from the UR5 manipulator. To compare the results of the PSO algorithm, the nonlinear least squares errors (NLSE) estimation algorithm is applied to identify the unknown parameters of the nonlinear models. The result shows that the PSO algorithm has higher identification accuracy than the NLSE estimation algorithm, and the model with identified parameters using the PSO algorithm accurately calculates the output torques of the joints of the manipulator.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Gravity Compensation of a 2r1t Mechanism With Remote Center of Motion for Minimally Invasive Transnasal Surgery Applications [article]
    (Cambridge University Press, 2023) Aldanmaz, Ataol Behram; Ayit, Orhan; Kiper, Gökhan; Dede, Mehmet İsmet Can
    This work addresses the gravity balancing of a 2R1T (2 rotations – 1 translation) mechanism with remote center of motion. A previously developed balancing solution is modified and applied to a prototype and test results are presented. The mechanism is an endoscope holder for minimally invasive transnasal pituitary gland surgery. In this surgery, the endoscope is inserted through a nostril of the patient through a natural path to the pituitary gland. During the surgery, it is vital for the manipulator to be statically balanced so that in case of a motor failure, the patient is protected against any harmful motion of the endoscope. Additionally, static balancing takes the gravitational load from the actuators and hence facilitates the control of the mechanism. The mechanism is a 2URRR-URR type parallel manipulator with three legs. The payload mass is distributed to the legs on the sides. By using counter-masses for two links of each leg, the center of mass of each leg is lumped on the proximal link which simplifies the problem to balancing of a two degree-of-freedom inverted pendulum. The two proximal links with the lumped mass are statically balanced via springs. Dynamic simulations indicate that when the mechanism is statically balanced, generated actuator torques are reduced by 93.5%. Finally, the balancing solution is implemented on the prototype of the manipulator. The tests indicate that the manipulator is statically balanced within its task space when the actuators are disconnected. When the actuators are connected, the torque requirements decrease by about 37.8% with balancing.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 4
    Comparative Proteomic Analysis of Leishmania Parasites Isolated From Visceral and Cutaneous Leishmaniasis Patients
    (Cambridge University Press, 2021) Dinç, Melike; Yalçın, Talat; Çavuş, İbrahim; Özbilgin, Ahmet
    Leishmaniasis is an infectious disease in which different clinical manifestations are classified into three main forms as visceral, cutaneous, and mucocutaneous. These disease forms are associated with parasite species of protozoan genus, Leishmania. For instance, Leishmania infantum and Leishmania tropica are typically linked with visceral (VL) and cutaneous (CL) leishmaniasis respectively, however these two species can also cause other form to a lesser extent. What is more alarming is this characteristic, which threatens classic diagnoses and therapies, is started to be acquired by other species. To address this issue, gel-based and gel-free proteomic analyses were carried out on the species, Leishmania infantum to determine the proteins differentiating between the parasites caused visceral and cutaneous leishmaniasis. In addition, Leishmania tropica parasites representing the typical cases for cutaneous leishmaniasis were included. Electrophoresis gels of parasites caused to visceral leishmaniasis were distinguishable from the others in terms of repetitive down-regulation on some specific locations. In addition, a distinct spot of an antioxidant enzyme, superoxide dismutase was shown up only on the gels of cutaneous leishmaniasis samples regardless of the species. In the gel-free approach, 37 proteins which were verified with a second database search using a different search engine, were distinguished from the comparison between VL and CL samples. Among them, 31 proteins for the CL group and 6 proteins for the VL group were determined differentially abundant. Two proteins from the gel-based analysis namely pyruvate kinase and succinly-coA:3-ketoacid-coenzyme A transferase analysis were encountered in the protein list of the CL group.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Investigation of Longitudinal Friction Characteristics of an Omnidirectional Wheel Via Lugre Model
    (Cambridge University Press, 2021) Şahin, Osman Nuri; Dede, Mehmet İsmet Can
    In recent years, omnidirectional wheels have found more applications in the design of automated guided vehicles (AGV). In this work, LuGre friction model is used for an omnidirectional wheel. A test setup that includes a single omnidirectional wheel is designed and constructed to identify the model parameters. With the help of the constructed test setup, the longitudinal friction characteristic of the omnidirectional wheel is obtained, and the model is verified via validation tests. In addition, for the first time, the effect of lateral frictional force on longitudinal motion is examined for an omnidirectional wheel through experiments.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Enumeration and Instantaneous Mobility Analysis of a Class of 3-Upu Parallel Manipulators With Equilateral Triangular Platforms
    (Cambridge University Press, 2022) Boztaş, Sercan; Kiper, Gökhan
    In this study, several joint axis orientations on equilateral platforms and the limbs of 3-UPU parallel manipulators (PMs) are examined. The generated joint layouts for the platforms were matched with each other to generate and enumerate manipulator architectures based on certain assumptions. The structures of thus obtained manipulators are examined and limb types were determined. These limb types were analyzed using screw theory. The instantaneous mobility of the manipulators and the motion characteristics of the moving platforms are tabulated. The finite mobility analysis of one of the manipulators is performed using a software package as an example. Among several different 3-UPU PM architectures, 118 novel 3-UPU PMs with non-parasitic 3-degrees-of-freedom are significantly important. The classified 3-UPU PMs with determined motion characteristics can be used by researchers as a design alternative for their specific design task. © The Author(s) 2021. Published by Cambridge University Press.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 6
    Use of Analogies, Metaphors, and Similes by Students and Reviewers at an Undergraduate Architectural Design Review
    (Cambridge University Press, 2019) Doğan, Fehmi; Taneri, Batuhan; Erbil, Livanur
    This study investigates the use of similarities in the form of analogy, metaphor, and simile by students and reviewers in an undergraduate architectural design review. In contrast to studies conducted in vitro settings, this study emphasizes the importance of studying analogies, metaphors, and similes in a natural setting. All similarity relationships were coded according to their type, the level of expertise, range, frequency, goal, value judgment, and depth. The results indicate that analogies, metaphors, and similes were used spontaneously and without any difficulty by both reviewers and students. Reviewers, however, were almost twice as likely to evoke similarities. Metaphor was the most frequently used similarity relationship among the three. It was found that there was a significant relationship between the level of expertise and type of similarity, with students more likely to use analogies and less likely to use similes. It was also found that goal is the most important factor, with a significant relation to all other variables, and that embodiment is often invoked in both students' and reviewers' metaphors. We conclude that design education should take full advantage of students' natural ability to benefit from similarity relationships.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 5
    Functionalization of Single-Layer Tas2 and Formation of Ultrathin Janus Structures
    (Cambridge University Press, 2020) Kahraman, Zeynep; Yağmurcukardeş, Mehmet; Şahin, Hasan
    Ab initio calculations are performed to investigate the structural, vibrational, electronic, and piezoelectric properties of functionalized single layers of TaS2. We find that single-layer TaS2 is a suitable host material for functionalization via fluorination and hydrogenation. The one-side fluorinated (FTaS2) and hydrogenated (HTaS2) single layers display indirect gap semiconducting behavior in contrast to bare metallic TaS2. On the other hand, it is shown that as both surfaces of TaS2 are saturated anti-symmetrically, the formed Janus structure is a dynamically stable metallic single layer. In addition, it is revealed that out-of-plane piezoelectricity is created in all anti-symmetric structures. Furthermore, the Janus-type single-layer has the highest specific heat capacity to which longitudinal and transverse acoustical phonon modes have contribution at low temperatures. Our findings indicate that single-layer TaS2 is suitable for functionalization via H and F atoms that the formed, anti-symmetric structures display distinctive electronic, vibrational, and piezoelectric properties.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 12
    Injective modules over down-up algebras
    (Cambridge University Press, 2010) Carvalho, Paula A.A.B.; Lomp, Christian; Pusat, Dilek
    The purpose of this paper is to study finiteness conditions on injective hulls of simple modules over Noetherian down-up algebras. We will show that the Noetherian down-up algebras A(α, β, γ) which are fully bounded are precisely those which are module-finite over a central subalgebra. We show that injective hulls of simple A(α, β, γ)-modules are locally Artinian provided the roots of X2 − αX − β are distinct roots of unity or both equal to 1.