scholarly journals KAJIAN KOMPUTASI POLA GELOMBANG RESONANSI MAGNET INTI (NMR) DENGAN TRANSFORMASI FOURIER

2018 ◽  
Vol 15 (1) ◽  
pp. 17
Author(s):  
Faprilia Khusnul ◽  
Salomo Salomo ◽  
Muhammad Hamdi
Keyword(s):  
Reference Data ◽  
Wave Pattern ◽  
Computational Approach ◽  
Physical Parameters ◽  
Mathematical Software ◽  
Transformation Equation ◽  
Nuclear Spins ◽  
J Coupling ◽  
Research Standards ◽  
J 24

Research on nuclear magnetic resonance (NMR) modeling has been done with computational approach. This study aims to determine the shape of signals and spectra of some of the combined nuclear spins. The physical parameters were determined using Fourier transformation equation modeled with the wolfram mathematical software 9.0. The relaxation time of the 1/2 nuclear spin was varied according to the nuclear state of cancer tissue.This produces a cosine wave pattern for the signal at T2 = 0.11 ms. Variations of this in chemical shift (Δ) and J-coupling (J) for modeling were performed in 9 times. The spectrum of one spin is generated at the value of Δ = 0.001 Hz and J = 0 Hz, the spectrum of two spins at Δ = 849,001 Hz and J = 24 Hz. These results can be applied to research interests for the medical world and as reference data for research standards.

scholarly journals ULS LiDAR SUPPORTED ANALYSES OF LASER BEAM PENETRATION FROM DIFFERENT ALS SYSTEMS INTO VEGETATION

2016 ◽  
Vol III-3 ◽  
pp. 233-239 ◽  
Author(s):  
M. Wieser ◽  
M. Hollaus ◽  
G. Mandlburger ◽  
P. Glira ◽  
N. Pfeifer
Keyword(s):  
Laser Scanning ◽  
Reference Data ◽  
Structural Characteristics ◽  
Laser System ◽  
Laser Scanner ◽  
Physical Parameters ◽  
Deciduous Trees ◽  
Airborne Laser Scanner ◽  
Vegetation Height ◽  
Airborne Laser

This study analyses the underestimation of tree and shrub heights for different airborne laser scanner systems and point cloud distribution within the vegetation column. Reference data was produced by a novel UAV-borne laser scanning (ULS) with a high point density in the complete vegetation column. With its physical parameters (e.g. footprint) and its relative accuracy within the block as stated in Section 2.2 the reference data is supposed to be highly suitable to detect the highest point of the vegetation. An airborne topographic (ALS) and topo-bathymetric (ALB) system were investigated. All data was collected in a period of one month in leaf-off condition, while the dominant tree species in the study area are deciduous trees. By robustly estimating the highest 3d vegetation point of each laser system the underestimation of the vegetation height was examined in respect to the ULS reference data. This resulted in a higher under-estimation of the airborne topographic system with 0.60 m (trees) and 0.55 m (shrubs) than for the topo-bathymetric system 0.30 m (trees) and 0.40 m (shrubs). The degree of the underestimation depends on structural characteristics of the vegetation itself and physical specification of the laser system.

scholarly journals ULS LiDAR SUPPORTED ANALYSES OF LASER BEAM PENETRATION FROM DIFFERENT ALS SYSTEMS INTO VEGETATION

2016 ◽  
Vol III-3 ◽  
pp. 233-239
Author(s):  
M. Wieser ◽  
M. Hollaus ◽  
G. Mandlburger ◽  
P. Glira ◽  
N. Pfeifer
Keyword(s):  
Laser Scanning ◽  
Reference Data ◽  
Structural Characteristics ◽  
Laser System ◽  
Laser Scanner ◽  
Physical Parameters ◽  
Deciduous Trees ◽  
Airborne Laser Scanner ◽  
Vegetation Height ◽  
Airborne Laser

This study analyses the underestimation of tree and shrub heights for different airborne laser scanner systems and point cloud distribution within the vegetation column. Reference data was produced by a novel UAV-borne laser scanning (ULS) with a high point density in the complete vegetation column. With its physical parameters (e.g. footprint) and its relative accuracy within the block as stated in Section 2.2 the reference data is supposed to be highly suitable to detect the highest point of the vegetation. An airborne topographic (ALS) and topo-bathymetric (ALB) system were investigated. All data was collected in a period of one month in leaf-off condition, while the dominant tree species in the study area are deciduous trees. By robustly estimating the highest 3d vegetation point of each laser system the underestimation of the vegetation height was examined in respect to the ULS reference data. This resulted in a higher under-estimation of the airborne topographic system with 0.60 m (trees) and 0.55 m (shrubs) than for the topo-bathymetric system 0.30 m (trees) and 0.40 m (shrubs). The degree of the underestimation depends on structural characteristics of the vegetation itself and physical specification of the laser system.

scholarly journals Supervised and Semi-Supervised Self-Organizing Maps for Regression and Classification Focusing on Hyperspectral Data

2019 ◽  
Vol 12 (1) ◽  
pp. 7 ◽  
Author(s):  
Felix M. Riese ◽  
Sina Keller ◽  
Stefan Hinz
Keyword(s):  
Land Cover ◽  
Reference Data ◽  
Ground Truth ◽  
Hyperspectral Data ◽  
Physical Parameters ◽  
Learning Approaches ◽  
Self Organizing Maps ◽  
Python Package ◽  
Self Organizing

Machine learning approaches are valuable methods in hyperspectral remote sensing, especially for the classification of land cover or for the regression of physical parameters. While the recording of hyperspectral data has become affordable with innovative technologies, the acquisition of reference data (ground truth) has remained expensive and time-consuming. There is a need for methodological approaches that can handle datasets with significantly more hyperspectral input data than reference data. We introduce the Supervised Self-organizing Maps (SuSi) framework, which can perform unsupervised, supervised and semi-supervised classification as well as regression on high-dimensional data. The methodology of the SuSi framework is presented and compared to other frameworks. Its different parts are evaluated on two hyperspectral datasets. The results of the evaluations can be summarized in four major findings: (1) The supervised and semi-Supervised Self-organizing Maps (SOM) outperform random forest in the regression of soil moisture. (2) In the classification of land cover, the supervised and semi-supervised SOM reveal great potential. (3) The unsupervised SOM is a valuable tool to understand the data. (4) The SuSi framework is versatile, flexible, and easy to use. The SuSi framework is provided as an open-source Python package on GitHub.

scholarly journals Analysis of a COVID-19 compartmental model: a mathematical and computational approach

2021 ◽  
Vol 18 (6) ◽  
pp. 7979-7998
Author(s):  
Zita Abreu ◽  
◽  
Guillaume Cantin ◽  
Cristiana J. Silva ◽  
Keyword(s):  
Mathematical Model ◽  
Compartmental Model ◽  
Equilibrium Points ◽  
Real Data ◽  
Computational Approach ◽  
Epidemic Models ◽  
Mathematical Software ◽  
System Of Differential Equations ◽  
Wide Range ◽  
The Stability

<abstract><p>In this note, we consider a compartmental epidemic mathematical model given by a system of differential equations. We provide a complete toolkit for performing both a symbolic and numerical analysis of the spreading of COVID-19. By using the free and open-source programming language Python and the mathematical software SageMath, we contribute for the reproducibility of the mathematical analysis of the stability of the equilibrium points of epidemic models and their fitting to real data. The mathematical tools and codes can be adapted to a wide range of mathematical epidemic models.</p></abstract>

scholarly journals ANALISA PENGARUH GAYA ELEKTROSTATIK PADA SPEKTRUM PENCITRAAN RESONANSI MAGNETIK (MRI) DALAM JARINGAN BIOLOGI

2019 ◽  
Vol 16 (1) ◽  
pp. 8
Author(s):  
Salomo Salomo ◽  
Nova Lestari ◽  
Muhammad Hamdi
Keyword(s):  
Electric Field ◽  
Magnetic Force ◽  
Magnetic Core ◽  
Computational Approach ◽  
Physical Parameters ◽  
Cancer Tissue ◽  
Resonance Imaging ◽  
Maximum Resolution ◽  
Spectrum Change ◽  
Magnetic Spectrum

A study of magnetic core resonance imaging modeling of biological tissue has been carried out in analyzing the effect of electrostatic forces with computational approach. This analysis aims to look at the effect of electric and magnetic force on the spectrum of breast cancer tissue. Physical parameters were determined using the modeled wave equation with the application of mathematical wolfram software 9. Computational or modeling results obtained 6 variations of the MRI spectrum showing the peak magnitude of the electric and magnetic spectrum changes by varying the resolution and distance. This is evidenced from the maximum resolution range ie the peak of the electric field spectrum at amplitude 25 a.u is at a concentration of 5 ppm. Resolution of spectrum peak medium is at concentration of 3-4 ppm whereas minimum resolution has 4 peak spectrum that is at concentration 1-2 ppm, 2-3ppm, 3-4ppm and 4ppm. the result of MRI spektrum for distance variation resulted in spectrum change, further reduced the distance then the mri spectrum in magnetic and electric field approaching spin 1.

Study on the Controllability of Complex Flexible Hydraulic Vehicle Robot System and its Dynamic Simulation

2011 ◽  
Vol 308-310 ◽  
pp. 1836-1842
Author(s):  
Zhen Shu Ma ◽  
Jian Bin Hao ◽  
Hua Gang Sun
Keyword(s):  
State Space ◽  
Dynamic Simulation ◽  
Reference Data ◽  
Physical Parameters ◽  
Flexible Robot ◽  
Hydraulic Actuator ◽  
Input Matrix ◽  
Robot System ◽  
Precise Control ◽  
Space Equation

Based on elastic dynamic model, an elastic dynamic controllable model of the vehicle flexible robot system was established. Regarding the low-order modes as the control modes, setting the boundary coordinates in the locations of the hydraulic actuator, the controllable state-space equations of the system was formed. A precondition for realizing system’s precise control is that the system is controllable. According to system’s controllability discriminant qualification, the influence of physical parameters on the controllability of system got broad discussed, and some reference data was obtained, which would be helpful for the next step to control the vibration. Aiming at the interference of the state-space equations, disturb distributing matrix was merged with input matrix, disturb vectors was merged with input vectors, a new state-space equation was established. By dynamic simulation, vibration response of the vehicle flexible robot system was achieved, and the experimental results showed that the treatment about disturb distributing matrix is feasible.

Some Results of the Spectroscopic Study of Four Close Binary Systems of Early Spectral Types

1965 ◽  
Vol 5 ◽  
pp. 120-130
Author(s):  
T. S. Galkina
Keyword(s):  
Spectroscopic Study ◽  
Spectral Type ◽  
Spectroscopic Investigation ◽  
Binary Systems ◽  
Quantitative Information ◽  
Close Binary ◽  
Physical Parameters ◽  
Absorption And Emission ◽  
Close Binary Systems ◽  
Quantitative Estimates

It is necessary to have quantitative estimates of the intensity of lines (both absorption and emission) to obtain the physical parameters of the atmosphere of components.Some years ago at the Crimean observatory we began the spectroscopic investigation of close binary systems of the early spectral type with components WR, Of, O, B to try and obtain more quantitative information from the study of the spectra of the components.

Application of Modified Bloch Waves to Image Analysis of Extended Linear Defects

1974 ◽  
Vol 32 ◽  
pp. 402-403
Author(s):  
S. Nakahara ◽  
D. M. Maher
Keyword(s):  
Image Analysis ◽  
Computational Approach ◽  
Dislocation Loops ◽  
Plane Wave Expansion ◽  
Dynamical Equations ◽  
Bloch Waves ◽  
Linear Defects ◽  
Imperfect Crystal ◽  
Localized Defects ◽  
Defective Crystals

Since Head first demonstrated the advantages of computer displayed theoretical intensities from defective crystals, computer display techniques have become important in image analysis. However the computational methods employed resort largely to numerical integration of the dynamical equations of electron diffraction. As a consequence, the interpretation of the results in terms of the defect displacement field and diffracting variables is difficult to follow in detail. In contrast to this type of computational approach which is based on a plane-wave expansion of the excited waves within the crystal (i.e. Darwin representation ), Wilkens assumed scattering of modified Bloch waves by an imperfect crystal. For localized defects, the wave amplitudes can be described analytically and this formulation has been used successfully to predict the black-white symmetry of images arising from small dislocation loops.

A theory of contamination in electron microscopes by surface diffusion

1978 ◽  
Vol 36 (1) ◽  
pp. 116-117
Author(s):  
J.T. Fourie
Keyword(s):  
Electron Beam ◽  
Surface Diffusion ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Physical Parameters ◽  
Carbon Compounds ◽  
Hydrocarbon Molecules ◽  
Electron Microscopes ◽  
Primary Electrons ◽  
Long Chain

Contamination in electron microscopes can be a serious problem in STEM or in situations where a number of high resolution micrographs are required of the same area in TEM. In modern instruments the environment around the specimen can be made free of the hydrocarbon molecules, which are responsible for contamination, by means of either ultra-high vacuum or cryo-pumping techniques. However, these techniques are not effective against hydrocarbon molecules adsorbed on the specimen surface before or during its introduction into the microscope. The present paper is concerned with a theory of how certain physical parameters can influence the surface diffusion of these adsorbed molecules into the electron beam where they are deposited in the form of long chain carbon compounds by interaction with the primary electrons.

Electron Microscopy in the Study of Natural Phytoplankton Assemblages

1985 ◽  
Vol 43 ◽  
pp. 620-623
Author(s):  
Linda Sicko-Goad
Keyword(s):  
Electron Microscopy ◽  
Aquatic Environment ◽  
Size Range ◽  
Physical Parameters ◽  
Specific Information ◽  
Phytoplankton Assemblages ◽  
Phytoplankton Productivity ◽  
Ecosystem Effects ◽  
Time Of Year ◽  
Species Specific

Although the use of electron microscopy and its varied methodologies is not usually associated with ecological studies, the types of species specific information that can be generated by these techniques are often quite useful in predicting long-term ecosystem effects. The utility of these techniques is especially apparent when one considers both the size range of particles found in the aquatic environment and the complexity of the phytoplankton assemblages.The size range and character of organisms found in the aquatic environment are dependent upon a variety of physical parameters that include sampling depth, location, and time of year. In the winter months, all the Laurentian Great Lakes are uniformly mixed and homothermous in the range of 1.1 to 1.7°C. During this time phytoplankton productivity is quite low.

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