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91.
The point-in-polygon problem is often encountered in geographical information systems. The algorithms usually work on polygons defined by straight edges. In some situations, however, polygons containing circular arcs are applied. In geographical information systems these polygons are usually considered as geometric buffers, geodesic offsets, or geodesic parallels. This paper presents three algorithms suitable for providing information about the containment of a point in geometric buffers: the Ray-crossing method, the Cell-Based Algorithm and the Approximate approach. An extensive experimental section allows the reader to select the most efficient algorithm for practical problems. 相似文献
92.
Processing-induced residual stresses play an important role in the production and performance of thermally sprayed coatings.
Their precise determination is a key to influence the coating properties by modification of process variables and to understand
the processing-structure-property relationship. Among various methods for residual stress measurement, x-ray diffraction holds
a specific position as being non-destructive, phase distinctive, localized, and applicable for real parts. The sin2 ω methods is commonly applied for bulk materials as well as coatings. However, the results are often reported without sufficient
experimental details and the method is used in its simplified form without justification of certain assumptions.
In this investigation, the sin2 ω x-ray diffraction method was used to measure residual macrostress in plasma sprayed metallic (nickel, NiCrAlY, and molybdenum)
and ceramic (ZrO2 + 8% Y2O3) coatings. Reproducibility of the method was tested and the assumptions allowing its use are discussed and experimentally
verified. For nickel coatings, a comparison with hole drilling and neutron diffraction measurements is presented. The influence
of processing factors such as deposition temperature and coating thickness is studied and the results are discussed. 相似文献
93.
Arthur Merkel Ladislav opk Daniil Golubenko Luk Dvok Matej Vavro Andrey Yaroslavtsev Libor eda 《International journal of molecular sciences》2022,23(11)
In the present study, the possibility of using a spiral-wound diffusion dialysis module was studied for the separation of hydrochloric acid and Zn2+, Ni2+, Cr3+, and Fe2+ salts. Diffusion dialysis recovered 68% of free HCl from the spent pickling solution contaminated with heavy-metal-ion salts. A higher volumetric flowrate of the stripping medium recovered a more significant portion of free acid, namely, 77%. Transition metals (Fe, Ni, Cr) apart from Zn were rejected by >85%. Low retention of Zn (35%) relates to the diffusion of negatively charged chloro complexes through the anion-exchange membrane. The mechanical and transport properties of dialysis FAD-PET membrane under accelerated degradation conditions was investigated. Long-term tests coupled with the economic study have verified that diffusion dialysis is a suitable method for the treatment of spent acids, the salts of which are well soluble in water. Calculations predict significant annual OPEX savings, approximately up to 58%, favouring diffusion dialysis for implementation into wastewater management. 相似文献
94.
Matej Kranjc Janja Dermol-erne Tjaa Poto
nik Vitalij Novickij Damijan Miklav
i
《International journal of molecular sciences》2022,23(17)
A high-intensity pulsed electromagnetic field (HI-PEMF) is a non-invasive and non-contact delivery method and may, as such, have an advantage over gene electrotransfer mediated by conventional electroporation using contact electrodes. Due to the limited number of in vitro studies in the field of gene electrotransfection by HI-PEMF, we designed experiments to investigate and demonstrate the feasibility of such a technique for the non-viral delivery of genetic material into cells in vitro. We first showed that HI-PEMF causes DNA adsorption to the membrane, a generally accepted prerequisite step for successful gene electrotransfection. We also showed that HI-PEMF can induce gene electrotransfection as the application of HI-PEMF increased the percentage of GFP-positive cells for two different combinations of pDNA size and concentration. Furthermore, by measuring the uptake of larger molecules, i.e., fluorescently labelled dextrans of three different sizes, we showed endocytosis to be a possible mechanism for introducing large molecules into cells by HI-PEMF. 相似文献
95.
Daube-Witherspoon ME Matej S Werner ME Surti S Karp JS 《IEEE transactions on medical imaging》2012,31(7):1461-1471
Early clinical results with time-of-flight (TOF) positron emission tomography (PET) systems have demonstrated the advantages of TOF information in PET reconstruction. Reconstruction approaches in TOF-PET systems include list-mode and binned iterative algorithms as well as confidence-weighted analytic methods. List-mode iterative TOF reconstruction retains the resolutions of the data in the spatial and temporal domains without any binning approximations but is computationally intensive. We have developed an approach [DIRECT (direct image reconstruction for TOF)] to speed up TOF-PET reconstruction that takes advantage of the reduced angular sampling requirement of TOF data by grouping list-mode data into a small number of azimuthal views and co-polar tilts and depositing the grouped events into histo-images, arrays with the sampling and geometry of the final image. All physical effects are included in the system model and deposited in the same histo-image structure. Using histo-images allows efficient computation during reconstruction without ray-tracing or interpolation operations. The DIRECT approach was compared with 3-D list-mode TOF ordered subsets expectation maximization (OSEM) reconstruction for phantom and patient data taken on the University of Pennsylvania research LaBr (3) TOF-PET scanner. The total processing and reconstruction time for these studies with DIRECT without attention to code optimization is approximately 25%-30% that of list-mode TOF-OSEM to achieve comparable image quality. Furthermore, the reconstruction time for DIRECT is independent of the number of events and/or sizes of the spatial and TOF kernels, while the time for list-mode TOF-OSEM increases with more events or larger kernels. The DIRECT approach is able to reproduce the image quality of list-mode iterative TOF reconstruction both qualitatively and quantitatively in measured data with a reduced time. 相似文献
96.
Low‐cycle fatigue life of thin‐plate auxetic cellular structures made from aluminium alloy 7075‐T651
Dejan Tomain
i
Branko Ne
emer Matej Vesenjak Jernej Klemenc 《Fatigue & Fracture of Engineering Materials & Structures》2019,42(5):1022-1036
In the article, the low‐cycle fatigue life durability of thin‐plate auxetic cellular structures is compared with the thin‐plate specimens of standard shape. Both the re‐entrant auxetic cellular structures and the standard specimens were cut from a 2‐mm‐thick strip of aluminium alloy 7075‐T651. First, a fatigue life curve and a cyclic curve were determined for the standard specimens. A special antibuckling device was applied to prevent the bending of the specimens. The same experimental arrangement was then applied to determine the low‐cycle fatigue life of auxetic structures. In the continuation, the most appropriate method was selected to calculate the fatigue life on the basis of the measured fatigue life curves. Abaqus and SIMULIA fe‐safe software were applied for this purpose. The best predictions for the standard specimens were obtained with the Brown‐Miller method. Finally, the selected method was applied to predict the low‐cycle fatigue life of re‐entrant auxetic cellular specimens. 相似文献
97.
Pucihar G Krmelj J Reberšek M Napotnik TB Miklavčič D 《IEEE transactions on bio-medical engineering》2011,58(11):3279-3288
Electroporation-based applications require the use of specific pulse parameters for a successful outcome. When recommended values of pulse parameters cannot be set, similar outcomes can be obtained by using equivalent pulse parameters. We determined the relations between the amplitude and duration/number of pulses resulting in the same fraction of electroporated cells. Pulse duration was varied from 150 ns to 100 ms, and the number of pulses from 1 to 128. Fura 2-AM was used to determine electroporation of cells to Ca(2+). With longer pulses or higher number of pulses, lower amplitudes are needed for the same fraction of electroporated cells. The expression derived from the model of electroporation could describe the measured data on the whole interval of pulse durations. In a narrower range (0.1-100 ms), less complex, logarithmic or power functions could be used instead. The relation between amplitude and number of pulses could best be described with a power function or an exponential function. We show that relatively simple two-parameter power or logarithmic functions are useful when equivalent pulse parameters for electroporation are sought. Such mathematical relations between pulse parameters can be important in planning of electroporation-based treatments, such as electrochemotherapy and nonthermal irreversible electroporation. 相似文献
98.
Repair welding of cold-work tool steels in cold is very risky and almost impossible by conventional processes. The application of pulse shaping in laser cladding with wire to avoid the solidification problems in relevant steel is demonstrated. The results show that sound remelting and/or cladding can be achieved by the right selection of laser parameters and pulse shape, i.e. long pulse duration, moderate pulse peak powers and ramped-down pulse shape. Despite the defects and softening in the cladding due to the formation of retained austenite, the cladding shows better wear resistance at lower loads compared to the heat-treated base material. 相似文献
99.
Sandra Castillo Peddinti GopalacharyuluLaxman Yetukuri Matej Oreši? 《Chemometrics and Intelligent Laboratory Systems》2011,108(1):23-32
Metabolomics encompasses the study of small molecules in a biological sample. Liquid Chromatography coupled with Mass Spectrometry (LC-MS) profiling is an important approach for the identification and quantification of metabolites from complex biological samples. The amount and complexity of data produced in an LC-MS profiling experiment demand automatic tools for the preprocessing, analysis, and extraction of useful biological information. Data preprocessing—a topic that covers noise filtering, peak detection, deisotoping, alignment, identification, and normalization—is thus an active area of metabolomics research. Recent years have witnessed development of many software for data preprocessing, and still there is a need for further improvement of the data preprocessing pipeline. This review presents an overview of selected software tools for preprocessing LC-MS based metabolomics data and tries to provide future directions. 相似文献
100.
Mirjana Babi Leko Matej Mihel
i Jasna Jurasovi Matea Nikolac Perkovi Ena pani Ankica Sekovani Tatjana Orct Klara Zub
i Lea Langer Horvat Nikolina Plei Spomenka Kiemet-Piska
eljka Vogrinc Nela Pivac Andrea Diana Fran Borove
ki Patrick R. Hof Goran imi 《International journal of molecular sciences》2023,24(1)