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Yayın A point cloud filtering method based on anisotropic error model(John Wiley and Sons Inc, 2023-12) Özendi, Mustafa; Akça, Devrim; Topan, HüseyinMany modelling applications require 3D meshes that should be generated from filtered/cleaned point clouds. This paper proposes a methodology for filtering of terrestrial laser scanner (TLS)-derived point clouds, consisting of two main parts: an anisotropic point error model and the subsequent decimation steps for elimination of low-quality points. The point error model can compute the positional quality of any point in the form of error ellipsoids. It is formulated as a function of the angular/mechanical stability, sensor-to-object distance, laser beam's incidence angle and surface reflectivity, which are the most dominant error sources. In a block of several co-registered point clouds, some parts of the target object are sampled by multiple scans with different positional quality patterns. This situation results in redundant data. The proposed decimation steps removes this redundancy by selecting only the points with the highest positional quality. Finally, the Good, Bad, and the Better algorithm, based on the ray-tracing concept, was developed to remove the remaining redundancy due to the Moiré effects. The resulting point cloud consists of only the points with the highest positional quality while reducing the number of points by factor 10. This novel approach resulted in final surface meshes that are accurate, contain predefined level of random errors and require almost no manual intervention.Yayın An automatic calibration procedure of driving behaviour parameters in the presence of high bus volume(Faculty of Transport and Traffic Engineering, 2019-11) Dadashzadeh, Nima; Ergün, Murat; Kesten, Ali Sercan; Zura, MarijanMost of the microscopic traffic simulation programs used today incorporate car-following and lane-change models to simulate driving behaviour across a given area. The main goal of this study has been to develop an automatic calibration process for the parameters of driving behaviour models using metaheuristic algorithms. Genetic Algorithm (GA), Particle Swarm Optimization (PSO), and a combination of GA and PSO (i.e. hybrid GAPSO and hybrid PSOGA) were used during the optimization stage. In order to verify our proposed methodology, a suitable study area with high bus volume on-ramp from the 0-1 Highway in Istanbul has been modelled in VISSIM. Traffic data have been gathered through detectors. The calibration procedure has been coded using MATLAB and implemented via the VISSIM-MATLAB COM interface. Using the proposed methodology, the results of the calibrated model showed that hybrid GAPSO and hybrid PSOGA techniques outperformed the GA-only and PSO-only techniques during the calibration process. Thus, both are recommended for use in the calibration of microsimulation traffic models, rather than GA-only and PSO-only techniques.Yayın Elucidation of the complete set of H-2 electronic states' vibrational data(Pergamon-Elsevier Science Ltd, 2004-11) Yarman, Nuh TolgaWe have previously established that, the vibration period T of a diatomic molecule, can be expressed as T = [4pi(2)/(rootninjh)]rootgM(0)m(e)r(2), where M-0 is the reduced mass of the nuclei, M-e the mass of the electron, r the internuclear distance of the molecule at the given electronic state, It the Planck Constant, and g a dimensionless and relativistically invariant coefficient, which appears to be a characteristic of the electronic configuration of the molecule. Herein we validate this relationship, chiefly on the basis of vibrational data of H-2 molecule's electronic states, and achieve its calibration, vis-a-vis the quantum numbers that it is to involve. This, basically yields, the elucidation of the complete set of H-2 spectroscopic data. Thus, the composite quantum number n(1)n(2) along our finding is nothing but the ratio of the internuclear distance r at the given electronic state, to the internuclear distance r(0) at the ground state. This makes that for electronic states configured alike, for which g is expected to remain the same, T-2 versus r(3), should exhibit a linear behavior. Our approach can well be applied to other molecules.Yayın Potassium determinations using sem, faas and xrf: some experimental notes(University of Aegean, 2011) Liritzis, Ioannis; Mavrikis, D; Zacharias, Nikolaos; Sakalis, Anastasios; Tsirliganis, Nestor C.; Polymeris, George S.The calibration of Scanning Electron Microscopy coupled with Energy Dispersive X-Rays Spectrometry (SEM-EDS) for elemental quantitative analysis is an important task for characterization, provenance and absolute dating purposes. In particular the potassium determination is an important contributor to dose rate assessments in luminescence and Electron Spin Resonance (ESR) dating. Here a SEM-EDX is calibrated on different archaeological and geoarchaeological materials against standard laboratory samples as well as measured by micro X-Rays Fluorescence (mu XRF) and flame atomic absorption spectroscopy (FAAS) techniques. A common linear relationship is obtained for most elements and certain rock types used and two clear linear regressions for two types of rocks; one for granite, diorite, microgranite and sediments and another ceramic sherds, soils, marble schists, breccia. Such linear regressions become readily available for a future fast, efficient and accurate way of potassium determination.
