Filtry
wszystkich: 1450
-
Katalog
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: SPECT
-
Confronting representative spectral structures of vocal tract pulse responses
PublikacjaArtykuł niniejszy jest kolejnym w cyklu prac publikowanych na łamach Materiałów OSA, które poświęcono problemowi klasyfikacji formalnej leksemów odmiennych języków.W pracy omówiono metody i rezultaty automatycznego kwalifikowania wybranych leksemów trzech systemów języka na podstawie konfrontowania ich cyfrowych reprezantacji.
-
Confronting representative spectral structures of vocal tract pulse responses
Publikacja -
Confronting representative spectral structures of vocal tract pulse responses
Publikacja -
The dynamic analysis of a cracked Timoshenko beam by the spectral element method
Publikacja -
Spectral density distribution moments as novel descriptors for QSAR/QSPR
Publikacja -
Frequency based criterion for distinguishing tonal and noisy spectral components
PublikacjaA frequency-based criterion for distinguishing tonal and noisy spectral components is proposed. For considered spectral local maximum two instantaneous frequency estimates are determined and the difference between them is used in order to verify whether component is noisy or tonal. Since one of the estimators was invented specially for this application its properties are deeply examined. The proposed criterion is applied to the...
-
Spectral Wave Energy Dissipation due to Under-Ice Turbulence
Publikacja -
Spectral properties of Cr3+ in SrLaGaO4 under high hydrostatic pressure.
Publikacja -
The comparative study of different methods of spectral analysis of electrochemical oscillations
PublikacjaOscylacje elektrochemiczne często połączone są z roztwarzaniem metali. One często wykazują niestacjonarny charakter. W związku z czym wydaje się konieczne wykonanie analizy w równoczesnej dziedzinie czasu i częstotliwości. Zaprezentowano porównanie trzech nowych metod: STFT, transformacji falkowej i rozkładu Wigner-Ville´a. Zalety tych metod zostały wypunktowane oraz wykazane zostały różnice pomiędzy analizą Fourierowską i technikami...
-
Influence of the Spectral Quality of Light on Daytime Alertness Levels in Humans
PublikacjaExposure to light is very important for human health. However, the characteristics of the light stimulus and the appropriate timing of such exposure are essential. Studies that have used monochromatic light exposure have shown no systematic patterns for the effects of blue light compared to longer wavelengths. Previous studies have shown that red light exposure increases objective and subjective measures of alertness at night without...
-
The equivariant spectral flow and bifurcation of periodic solutions of Hamiltonian systems
PublikacjaWe define a spectral flow for paths of selfadjoint Fredholm operators that are equivariant under the orthogonal action of a compact Lie group as an element of the representation ring of the latter. This G-equivariant spectral flow shares all common properties of the integer valued classical spectral flow, and it can be non-trivial even if the classical spectral flow vanishes. Our main theorem uses the G-equivariant spectral flow...
-
Towards spectral sensitivity curve for two-photon vision mechanism
PublikacjaAbstract Purpose: The perceived brightness of different visible light sources can be compared with photometric units based on the standardized luminosity curves (300-780nm range). As reported previously (PNAS 111(50), pp. E5445-E5454 (2014)), near-infrared (NIR) radiation can cause isomerization of visual pigments by one- or two-photon absorption. The perceived color of the stimulus is red in the case of one-photon vision (1PV)...
-
Correlated Particle Motion and THz Spectral Response of Supercritical Water
PublikacjaMolecular dynamics simulations of supercritical water reveal distinctly different distance-dependent modulations of dipolar response and correlations in particle motion compared to ambient conditions. The strongly perturbed H-bond network of water at supercritical conditions allows for considerable translationaland rotational freedom of individual molecules. These changes give rise to substantially different infrared spectra and...
-
Fiber optic displacement sensor with signal analysis in spectral domain
PublikacjaIn this paper, a study of a low-coherence fiber optic displacement sensor is presented. The sensor consisted of a broadband source whose central wavelength was either at 1310 nm or 1550 nm, a sensing Fabry-Pérot interferometer operating in reflective mode and an optical spectrum analyzer acting as the detection setup. All these components were connected by a single-mode fiber coupler. Metrological parameters of the sensor were...
-
Spectral Finite Element Method in Condition Monitoring and Damage Detection
PublikacjaIt is well known that the dynamic behaviour of engineering structures may carry very important and crucial information that can be further used for the assessment of their condition as well as detection of any damage induced. The current interest in monitoring techniques based on the propagation of guided elastic waves requires that numerical techniques used for modelling the phenomena associated must shift into the realm of high...
-
Spectral measurement of birefringence using particle swarm optimization analysis
PublikacjaThe measurement of birefringence is useful for the examination of both technical and biological objects. One of the main problems is that the polarization state of light in birefringent media changes periodically. Without the knowledge of the period number, the birefringence of a given medium cannot be determined reliably. We propose to analyse the spectrum of light in order to determine the birefringence. We use a Particle Swarm...
-
Spectral plate element for crach detection with use of propagation wares.
PublikacjaW pracy przedstawiono model płyty oparty na metodzie elementów spectralnych. Przedstawiono wyniki analizy interakcji pęknięcia zmęczeniowego i propagującej się fali.
-
The dynamic analysisi of cracked Thimoshenko beam by the spectral element method.
PublikacjaW pracy przedstawiono model belli Timoshenko z pęknięciem poprzecznym oparty o metodę elementów spektralnych. Przedstawiono wyniki propagacji fali sprężystej i jej interakcję z pęknięciem.
-
MASS SPECTROMETRY REVIEWS
Czasopisma -
Low-temperature spectroscopic and scintillation characterisation of Ti-doped Al2O3
Publikacja -
Spectroscopic investigation of hydrothermally synthesized zeolites from expanded perlite
Publikacja -
Cobalt(II) silanethiolato complexes with dimethylpyridines:crystal structures and spectroscopic studies
PublikacjaTri-tert-butoksysilanotiolany kobaltu(II) z 2,5-dimetylopirydną, 3,4-dimetylopirydną i 3,5-dimetylopirydną jako dodatkowymi ligandami zostały zsyntetyzowane w reakcji z bimetalicznym [Co{SSi(OtBu)3}(NH3)]2 z odpowiednią pochodną pirydyny. Kompleksy zostały zcharakteryzowane za pomocą rentgenografii strukturalnej, analizy elementarnej, spektroskopii FT-IR oraz UV-vis. Prezentowane kompleksy są cztero- i pięciokoordynacyjne o rdzeniu...
-
Spectroscopic and photophysical properties of ZNTPP in a room temperature ionic liquid
PublikacjaThe steady-state absorption and emission spectra and the time-resolved Soret- and Q-band excited fluorescence profiles of the model metalloporphyrin, ZnTPP, have been measured in a highly purified sample of the common room temperature ionic liquid, [bmim][PF(6)]. S(2)-S(0) emission resulting from Soret-band excitation behaves in a manner completely consistent with that of molecular solvents of the same polarizability. The ionic...
-
Spectroscopic properties and energy level location of Eu2+ in Sr2Si5N8 phosphor
Publikacja -
Spectroscopic and quantum chemical study of phthalocyanines with 1,4,7-trioxanonyl moieties
Publikacja -
Spectroscopic investigations into degradation of polymer membranes for fuel cells applications
Publikacja -
Doping-Induced Immobile Charge Carriers in Polyazomethine: A Spectroscopic Study
Publikacja -
Spectroscopic and Physicochemical Investigations of Azomethines with Triphenylamine Core towards Optoelectronics
Publikacja -
Raman spectroscopic study of Ni2+-DNA interactions in aqueous systems
PublikacjaMetodą ramanowskich widm różnicowych określono sposób oddziaływania jonu Ni2+ z DNA(CT) w układach wodnych. Kation Ni(II) koordynuje w pozycjach N7 guaniny (G) i adeniny (A) w powtarzających się sekwencjach GG, AA i GA cząsteczki DNA. Jednocześnie Ni2+ oddziałuje zewnątrz sferowo poprzez cząsteczki wody z grupami fosforanowymi DNA.
-
Spectroscopic Optical Coherence Tomography for Thin Layer and Foil Measurements
PublikacjaThe main goal of this research was to assess if it is possible to evaluate the thickness of thin layers (both thin films on the surface and thin layers below the surface of the tested object) and foils using optical coherence tomography (OCT) for thickness assessment under the resolution of the standard commercially available OCT measurement system. In the proposed solution, light backscattered from the evaluated thin layer has...
-
Parallel multithread computing for spectroscopic analysis in optical coherence tomography
PublikacjaSpectroscopic Optical Coherence Tomography (SOCT) is an extension of Optical Coherence Tomography (OCT). It allows gathering spectroscopic information from individual scattering points inside the sample. It is based on time-frequency analysis of interferometric signals. Such analysis requires calculating hundreds of Fourier transforms while performing a single A-scan. Additionally, further processing of acquired spectroscopic information...
-
Microcrystalline diamond film evaluation by spectroscopic optical coherence tomography
PublikacjaThis study has focused on the microcrystalline diamond film (MCD) thickness evaluation. For this purpose, optical coherence tomography (OCT) enhanced by spectroscopic analysis has been used as a method of choice. The average thickness of the tested layer was about 1.5 µm, which is below the standard 2-point OCT resolution. In this case, the usefulness of the spectroscopic analysis was confirmed for the evaluation of the thickness...
-
Sensing the onset of epoxy coating degradation with combined Raman spectroscopy/atomic force microscopy/electrochemical impedance spectroscopy
PublikacjaThe paper presents the results of investigation on epoxy resin durability upon 12-week exposure to UV radiation. The aim was early determination of the onset of epoxy degradation and for this purpose an epoxy film on steel substrate systems were periodically inspected using Raman spectroscopy, atomic force microscopy and electrochemical impedance spectroscopy. The behaviour of examined polymer could be divided into three periods: immunity,...
-
FTIR (Fourier-transform infrared spectroscopy) spectra of titanium dioxide coated nickel foams.
Dane BadawczeThis dataset contains FTIR spectra recorded on a JASCO 4200 spectrometer of nickel foams coated with titanium dioxide after heating at 400, 500 and 600 C and after photocatalytic process with NOx.
-
CdWO/sub 4/ crystal in gamma-ray spectrometry
Publikacja -
Application of deep eutectic solvents in atomic absorption spectrometry
PublikacjaAtomic absorption spectrometry (AAS) is a widely applied technique for metal quantification due to its practicality, easy use and low cost. However, to improve the metrological characteristics of AAS, in particular the sensitivity and the detection limit, sample pretreatment is commonly used before the detection step itself. In consideration of the principles of Green Analytical Chemistry, new solvents are being introduced into...
-
Proton Transfer Reaction Mass Spectrometry for Plant Metabolomics
PublikacjaVolatile organic compounds (VOCs) emitted by plants are a valuable source of information on their growth, theirresponse to stress, and the condition of their habitat. The recent trend in the analysis of low-mass molecules ofplant origin is metabolomics, which in the context of volatiles is often referred to as volatolomics. It requires theuse of modern analytical instrumentation...
-
Mixture Model Based Efficient Method for Magnetic Resonance Spectra Quantification
Publikacja -
Analyze of Maldi-TOF Proteomic Spectra with Usage of Mixture of Gaussian Distributions
Publikacja -
Threshold photoelectron spectra of tetrahydrofuran over the energy range 9-29eV
PublikacjaWykonano pomiary fotoelektronowe widm progowych tetrahydrofuranu C4H8O w zakresie energii fotonów 9-29 eV przy użyciu promieniowania synchrotronowego. Zaobserwowano nowe pasma jonizacyjne w zakresie energii 16-26eV
-
Luminescence Spectra of β-SiAlON/Pr3+ Under High Hydrostatic Pressure
Publikacja -
High pressure and time resolved luminescence spectra of Gd3Ga5O12:Pr3+ crystal
Publikacja -
High pressure luminescence spectra of CaMoO4:Ln3+(Ln = Pr, Tb)
Publikacja -
TL, OSL and RL emission spectra of RE-doped LiMgPO4 crystals
Publikacja -
Analysis of experimental and simulated vibrational spectra for the antiferroelectric liquid crystal 12OBBB1M6
Publikacja -
Theoretical interpretations of photoelectron spectra of platinum atom, its cation and anion
Publikacja -
Relativistic calculations of X-ray photoelectron spectra and the accuracy of the IOTC method*
Publikacja -
Vapor correction of FTIR spectra – A simple automatic least squares approach
PublikacjaFTIR spectroscopy is one of the best techniques to study intermolecular interactions. However, such an application requires high quality spectra with as little noise as possible, which are often difficult to obtain. One of the main sources of unwanted interference is water vapor. Here a robust method is proposed for automatic, fast and reliable vapor correction of FTIR spectra. The presented least squares approach of vapor subtraction...
-
Consideration of dynamic loads in the determination of axle load spectra for pavement design
PublikacjaAxle load spectra constitute a crucial part of the data for pavement design and pavement distress analysis. Typically, axle load spectra represent static load from vehicles and do not include dynamic loads generated by vehicles in motion. While dynamic loads can significantly contribute to faster pavement distress, this fact is mostly omitted in pavement design methods. The paper presents a methodology for consideration of dynamic...
-
STUDY OF CuO AND V2O5 EFFECT ON IR SPECTRA OF POLYCRYSTALLINE BISMUTH NIOBATE
PublikacjaBismuth niobate (BiNbO4) ceramics were fabricated by mixed oxide method and sintered by presureless sintering method. BiNbO4 ceramics doped with V2O5 additive in amount 0.125 wt%, 0.250 wt% and 1 wt% of was sintered at T = 910°C whereas BiNbO4 ceramics doped with 2 wt% of CuO additive was sintered at T = 890°C and T = 910°C. It was found that V2O5 additive improved morphology of the ceramic samples. However, the chemical composition...