Arama Sonuçları

Listeleniyor 1 - 10 / 127
  • Yayın
    On the sensitivity of desirability functions for multiresponse optimization
    (American Institute of Mathematical Sciences, 2008-11) Aksezer, Sezgin Çağlar
    Desirability functions have been one of the most important multiresponse optimization technique since the early eighties. Main reasons for this popularity might be counted as the convenience of the implementation of the method and it's availability in many experimental design software packages. Technique itself involves somehow subjective parameters such as the importance coefficients between response characteristics that are used to calculate overall desirability, weights used in determining the shape of each individual response and the size of the specification band of the response. However, the impact of these sensitive parameters on the solution set is mostly uninvestigated. This paper proposes a procedure to analyze the sensitivity of the important characteristic parameters of desirability functions and their impact on pareto-optimal solution set. The proposed procedure uses the experimental design tools on the solution space and estimates a prediction equation on the overall desirability to identify the sensitive parameters. For illustration, a classical desirability example is selected from the literature and results are given along with the discussion.
  • Yayın
    A survey of algorithms and architectures for H.264 sub-pixel motion estimation
    (World Scientific, 2012-05) Fatemi, Mohammad Reza Hosseiny; Ateş, Hasan Fehmi; Salleh, Rosli Bin
    This paper reviews recent state-of-the-art H. 264 sub-pixel motion estimation (SME) algorithms and architectures. First, H.264 SME is analyzed and the impact of its functionalities on coding performance is investigated. Then, design space of SME algorithms is explored representing design problems, approaches, and recent advanced algorithms. Besides, design challenges and strategies of SME hardware architectures are discussed and promising architectures are surveyed. Further perspectives and future prospects are also presented to highlight emerging trends and outlook of SME designs.
  • Yayın
    The effect of the interaction between autistic traits and psychotic proneness on empathy: a cross-sectional study with a non-clinical sample
    (Emerald Publishing, 2023-11-08) Yıldırım, Elif
    Purpose: Recent evidence indicates an improving effect of the co-occurrence of autistic traits and psychotic symptoms on social cognition, but there is no agreement on the effect of the interaction between autistic traits and psychotic proneness on empathy. The aim of this study is to examine the effect of the interaction between autistic traits and positive psychotic experiences on cognitive and affective empathy. Design/methodology/approach: The sample consisted of 420 adults aged between 18 and 60. Assessments were administered anonymously online. Empathic abilities were evaluated by the Interpersonal Reactivity Index (IRI). While Autism Spectrum Quotient (AQ) was applied to measure autistic traits, The Community Assessment of Psychic Experience (CAPE) was used as a measurement of positive psychotic experiences. Findings: A series of regression analyses showed that although AQ and CAPE scores were not correlated with cognitive-IRI, the interaction between these scores predicted cognitive-IRI scores. It was found that the personal distress subscale of IRI was significantly associated with AQ, but this relationship was moderated by CAPE scores. Originality/value: These findings provide a different perspective on understanding social cognitive impairments in autism, which may have potential clinical implications. Findings also contribute to explaining the individual differences in empathic abilities.
  • Yayın
    Design of a global extremum seeking algorithm for an omni-directional robot model
    (Romanian Soc Control Tech Informatics, 2017-06) Dinçmen, Erkin
    A global extremum seeking algorithm is developed for a mobile robot model where the aim is to find the location of the most powerful signal source among the others. In other words, the control problem is to seek the global extremum point of a performance function when there are local extremas. The locations of the signal sources and signal distribution characteristics are unknown, i.e. the gradient of the performance function is unknown. The control algorithm also doesn't use any position measurement of the mobile robot itself. Henceforth, the controller is suitable for the missions where the robot moves in an unknown terrain with no GPS signal and no inertial measurements. Only the signal magnitude should be measured via a sensor mounted on the robot during the motion. A gradient estimator is designed to determine the motion direction towards the extremum point. When a local extremum is found, the robot will continue its search for another extremum points. Once each extremums have been visited, the robot will compare the signal levels on each source and identify the global extremum i.e. the most powerful signal source. In the absence of any position measurements, the robot can move towards the global extremum by repeating its motion history backwards. In the literature, this is the first global extremum seeking algorithm that has been developed for an omni-directional mobile robot model. Via the simulation studies it has been shown that the control algorithm can seek and find both stationary and non stationary signal sources and it can find the global extremum point when there are local extremas.
  • Yayın
    Tulczyjew's triplet with an Ehresmann connection I: Trivialization and reduction
    (World Scientific, 2023-03-30) Esen, Oğul; Kudeyt, Mahmut; Sütlü, Serkan
    We study the trivialization and the reduction of Tulczyjew's triplet, in the presence of a symmetry and an Ehresmann connection associated to it. We thus establish a geometric pathway for the Legendre transformations on singular dynamical systems.
  • Yayın
    A designing practice and two coding practices for extreme programming (XP)
    (Springer Verlag, 2003) Yıldız, Mustafa; Kuru, Selahattin
    This paper introduces three new XP practices and reports the experience of applying them to web based software development. These are issue- based programming, comment-first coding and just in time code ownership. The example project is development of an on-line student information and registration software for a university.
  • Yayın
    Driver recognition using gaussian mixture models and decision fusion techniques
    (Springer-Verlag Berlin, 2008) Benli, Kristin Surpuhi; Düzağaç, Remzi; Eskil, Mustafa Taner
    In this paper we present our research in driver recognition. The goal of this study is to investigate the performance of different classifier fusion techniques in a driver recognition scenario. We are using solely driving behavior signals such as break and accelerator pedal pressure, engine RPM, vehicle speed; steering wheel angle for identifying the driver identities. We modeled each driver using Gaussian Mixture Models, obtained posterior probabilities of identities and combined these scores using different fixed mid trainable (adaptive) fusion methods. We observed error rates is low as 0.35% in recognition of 100 drivers using trainable combiners. We conclude that the fusion of multi-modal classifier results is very successful in biometric recognition of a person in a car setting.
  • Yayın
    Failure of an exchange-rate-based stabilization plan in Turkey
    (M E Sharpe, 2003-02) Gökkent, Giyas; Moslares, Carlos; Amiel-Saenz, Rafael
    The Turkish exchange-rate-based stabilization plan adopted in 2000 has been a spectacular failure, lasting a mere fourteen months despite a relatively flexible peg regime and preannounced exit strategy. The final three months of the currency regime were marred by the eruption of a banking sector crisis that quickly developed into a currency crisis, quelled only by external loans and a blanket guarantee by the sovereign of all banking sector liabilities. This was ultimately to no avail as the lira was allowed to float following a full-fledged currency crisis in late February 2001. The usual indicators of crisis did not point to imminent turmoil in November 2000 despite widespread concern about eventual dire developments. To identify the source of the November crisis, one must weigh the factors that led economic agents, and banks in particular, to expect higher interest rates after the fall.
  • Yayın
    Extremum seeking dead-zone pre-compensator for an industrial control system
    (Walter De Gruyter GMBH, 2018-06-26) Dinçmen, Erkin
    PID type industrial controllers such as PI, PD, PID are mature control algorithms and they are intensively used in industry due to their simplicity and easily implementability. However, they start to fail when there is an unknown or unpredictable nonlinear behavior in the plant or actuator. In this paper, a novel compensation algorithm is proposed for PD type industrial control systems, which possess an unknown dead-zone nonlinearity. An extremum-seeking technique is utilized in the compensation algorithm. The aim is to propose a new, effective and robust compensator which can be added easily to an existing industrial controller without any need to change/retune the controller settings/parameters. It is shown that by adding the compensator to an existing PD control system, the sensitivity of the controller to the dead-zone nonlinearity is removed.
  • Yayın
    Small molecule sorption and desorption in and out of iota-carrageenan gels
    (Taylor & Francis Group, 2007-08) Ataman, Evren; Pekcan, Mehmet Önder
    Small molecule sorption and desorption in and out of Iota-Carrageenan was studied by using steady-state fluorescence (SSF) technique. Pyranine dissolved in water used as fluorescence probe. Fluorescence emission intensity, I-p from pyranine was monitored for studying sorption and desorption processes at various temperatures. The Fickian model was applied to produce sorption, D-s, early desorption, D-ed, and desorption, D-d, coefficients. Corresponding activation energies were obtained and found to be 20.5 kJ mol(-1), 7.0 kJ mol(-1) and 34.9 kJ mol(-1), respectively. The observed D-ed value is an order of magnitude smaller than the D-s and D-d coefficients. On the other hand, sorption processes were shown to be twice as fast as desorption processes.