scholarly journals Decomposition and Classification of Spectral Lines in Astronomical Radio Data Cubes

2009 ◽  
pp. 189-198 ◽  
Author(s):  
Vincent Mazet ◽  
Christophe Collet ◽  
Bernd Vollmer
Keyword(s):  
Spectral Lines ◽  
Data Cubes ◽  
Radio Data

scholarly journals 9. The influence of exposure duration and trail orientation on photographic meteor spectra

1968 ◽  
Vol 33 ◽  
pp. 91-103
Author(s):  
I. Halliday
Keyword(s):  
Relative Intensity ◽  
Decay Time ◽  
Exposure Duration ◽  
Path Length ◽  
Spectral Lines ◽  
Metastable Level ◽  
Careful Attention ◽  
Long Duration ◽  
Effective Path

The effects on photographic meteor spectra produced by an occulting shutter and by the geometric orientation of the trail with respect to the camera are considered. A Perseid meteor photographed with both an occulted and unocculted spectrograph shows that large changes in the relative intensity of spectral lines can be caused by a shutter. The strong wake spectrum of this meteor is studied and a classification of multiplets according to duration and wake intensity is presented. It is emphazised that a strong wake is produced by a coasting gas rather than by particles or droplets. The gas may coast an appreciable distance during the radiating lifetime of some multiplets.The spectrum of a bright Quadrantid meteor is used to show that long-duration multiplets are strongly enhanced when the orientation of the trail lengthens the effective path length of the wake column, i.e., the meteor is observed near its radiant. The abundance of calcium appears to be above average in this meteor.Multiple photographs of the λ5577 line of neutral oxygen have been secured showing a decay time in excess of 1·5 sec. The decay is more rapid at lower heights and it appears that the mechanism of excitation to the metastable level operates for an interval of about 0·1 sec.As more accurate photometry of meteor spectra is achieved it will be essential to give careful attention to all of these effects.

Weighted-averaging-based classification of laser-induced breakdown spectroscopy measurements using most informative spectral lines

2019 ◽  
Vol 22 (1) ◽  
pp. 015501 ◽  
Author(s):  
Ekta SRIVASTAVA ◽  
Hyemin JANG ◽  
Sungho SHIN ◽  
Janghee CHOI ◽  
Sungho JEONG ◽  
...  
Keyword(s):  
Spectral Lines ◽  
Weighted Averaging ◽  
Laser Induced Breakdown Spectroscopy ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

Classification of some blended spectral lines of praseodymium

2015 ◽  
Vol 48 (13) ◽  
pp. 135001 ◽  
Author(s):  
Zaheer Uddin ◽  
Imran Siddiqui ◽  
Jaweria Tanweer ◽  
Saif Uddin Jilani ◽  
Laurentius Windholz
Keyword(s):  
Spectral Lines

Extensions to the spark spectra of zinc. I. Zinc II and zinc IV

1968 ◽  
Vol 46 (10) ◽  
pp. 1241-1251 ◽  
Author(s):  
A. M. Crooker ◽  
K. A. Dick
Keyword(s):  
Energy Level ◽  
Ground State ◽  
Level Scheme ◽  
Energy Levels ◽  
Spectral Lines ◽  
Energy Level Scheme ◽  
New Energy ◽  
Ground State Doublet

The spectrum of Zn II has been extended to complete the configuration 3d94s(3D)4p′ and 3d94s(1D)4p″. The configurations 3d109f, 3d1010f, and 3d94s(3D)5s′ have been added and a number of levels of the configurations 3d94s(3D)4d′, 3d94s(1D)4d″, and 3d94s(3D)6s′ have been tentatively established. Our list of Zn II lines contains 363 classified lines.Improved wavelength measurements have necessitated a revision of our earlier report on the spectrum of Zn IV. All the energy levels have been shifted slightly with respect to the ground state doublet 3d92D. In addition, 3 of 17 even levels and 10 of 43 odd levels have been changed. The new energy-level scheme results in the classification of 329 spectral lines as compared with 200 lines in the previous report.

scholarly journals A Clustering Method Applied to the Analysis of Planetary Nebulae

1993 ◽  
Vol 155 ◽  
pp. 44-44
Author(s):  
O.S. Yatsyk
Keyword(s):  
Planetary Nebula ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Planetary Nebulae ◽  
Spectral Lines ◽  
Radio Flux ◽  
Clustering Method ◽  
Centroid Method ◽  
Three Dimensional Space

Intensities of the observed spectral lines, radio fluxes and Hβ fluxes are used for the classification of planetary nebulae by centroid method of taxonomical analysis. Two variants of classification are proposed. The first one– in the three–dimensional space of relation of intensity of spectral lines He II λ 4686/HeI λ 4471, [OIII] λ 4959+5007/[OII] λ 3726+29, [OIII] λ 4959+5007/[OIII] 4363. The second variants is the classification in the three-dimensional space with cooordinates being radio flux, Hβ flux and [OIII] λ 4959+5007 intensity. The membership of classes (taxons) are presented. In the diagram joining the planetary nebula descriptors pairwise there are regions of complete (or predominant) of nebulae belonging to the same taxon, but there are also some regions of overlap. The corresponding taxons are not isolated but merge continuously into one another.

scholarly journals Application of Computational Intelligence Methods for the Automated Identification of Paper-Ink Samples Based on LIBS

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3670 ◽  
Author(s):  
Krzysztof Rzecki ◽  
Tomasz Sośnicki ◽  
Mateusz Baran ◽  
Michał Niedźwiecki ◽  
Małgorzata Król ◽  
...  
Keyword(s):  
Neural Network ◽  
Random Forest ◽  
Computational Intelligence ◽  
Probabilistic Neural Network ◽  
Spectral Lines ◽  
Support Vector ◽  
Generalized Regression Neural Network ◽  
K Nearest Neighbor ◽  
Computational Intelligence Methods

Laser-induced breakdown spectroscopy (LIBS) is an important analysis technique with applications in many industrial branches and fields of scientific research. Nowadays, the advantages of LIBS are impaired by the main drawback in the interpretation of obtained spectra and identification of observed spectral lines. This procedure is highly time-consuming since it is essentially based on the comparison of lines present in the spectrum with the literature database. This paper proposes the use of various computational intelligence methods to develop a reliable and fast classification of quasi-destructively acquired LIBS spectra into a set of predefined classes. We focus on a specific problem of classification of paper-ink samples into 30 separate, predefined classes. For each of 30 classes (10 pens of each of 5 ink types combined with 10 sheets of 5 paper types plus empty pages), 100 LIBS spectra are collected. Four variants of preprocessing, seven classifiers (decision trees, random forest, k-nearest neighbor, support vector machine, probabilistic neural network, multi-layer perceptron, and generalized regression neural network), 5-fold stratified cross-validation, and a test on an independent set (for methods evaluation) scenarios are employed. Our developed system yielded an accuracy of 99.08%, obtained using the random forest classifier. Our results clearly demonstrates that machine learning methods can be used to identify the paper-ink samples based on LIBS reliably at a faster rate.

On the chemical classification of the stars

1900 ◽  
Vol 65 (413-422) ◽  
pp. 186-191 ◽  
Keyword(s):  
Unknown Origin ◽  
Spectral Lines ◽  
Chemical Classification ◽  
Calcium Iron

In the attempts made to classify the stars by means of their spectra, from Rutherford’s time to quite recently, the various criteria selected were necessarily for the most part of unknown origin; with the excep­tion of hydrogen, calcium, iron, and carbon, in the main chemical origins could not be assigned with certainty to the spectral lines. Hence the various groups defined by the behaviour of unknown lines were referred to by numbers, and as the views of those employed in the work of classifying differed widely as to the sequence of the phenomena observed, the numerical sequences vary very considerably so that any co-ordination becomes difficult and confusing.

scholarly journals Расчет эффективности классификации целей интеллектуальной системой ВМФ, использующей комплекс вычислительных операций нейронных сетей

2020 ◽  
Author(s):  
V.A. Pyatakovich ◽  
V.F. Rychkova ◽  
A.V. Filippova ◽  
N.V. Pyatakovich
Keyword(s):  
Neural Network ◽  
Expert System ◽  
Monitoring System ◽  
Vlsi Circuits ◽  
Spectral Lines ◽  
Standard Normal Distribution ◽  
Practical Implementation ◽  
Surface Ship ◽  
Standard Normal

В данной статье рассмотрены показатели эффективности и предложена методология оценки радиогидроакустических средств при использовании их в общей структуре системы мониторинга, распознавания и классификации полей, генерируемых источниками в морской среде. Особенностью системы является привлечение аппарата нечеткой логики для решения задач классификации объектов нейросетевой экспертной системой совместно со спектральными линиями анализа приемного тракта разрабатываемой радиогидроакустической системы мониторинга морских акваторий с последующим комплексным анализом результатов в едином информационно-аналитическом центре. Результаты научных разработок авторов по данной тематике защищены патентами, изданы в виде монографий и отражены в научных статьях. Приведен расчет показателей эффективности обнаружения морской цели (надводного корабля, подводной лодки, специального морского аппарата) при различных условиях. Рассмотрены выражения показателя эффективности гидроакустических средств для различных видов функций полезности и аппроксимации характеристик обнаружения стандартным нормальным распределением. Реализация разрабатываемого комплекса вычислительных операций нейронных сетей на многопроцессорных нейроподобных сверхбольших интегральных схемах в виде нейросетевой экспертной системы для распознавания и классификации измеряемых информационных полей морских объектов системой мониторинга морских акваторий, обеспечит возможность решения многофункциональных задач морской науки и оборонного комплекса государства.In this article, the efficiency indicators are considered and a methodology for estimating radio-hydroacoustic means is proposed when using them in the overall structure of the monitoring system, recognition and classification of fields generated by sources in the marine environment.The peculiarity of the developed system is of fuzzy logic to solve problems of object classification by the neural network expert system in conjunction with spectral lines of analysis of the receive path of the developed radio-hydroacoustical system for the monitoring of sea waters, with subsequent comprehensive analysis of results at an integrated Information and Analytical center. The results of scientific research of the authors on this topic are protected by patents and published in the form of monographs and scientific articles. The article discusses the study of factors that affect the functionality of the marine monitoring system with elements of artificial intelligence and influence detection and recognition that make up the process of identifying a marine target. The effectiveness of detecting a marine target (a surface ship, a submarine, a special marine apparatus) under various conditions has been calculated. Expressions to calculate the effectiveness of hydroacoustic means for various utility functions and approximation of detection characteristics using standard normal distribution are presented. The practical implementation of the system that is developed for executing the computing operations by way of neural networks on the multiprocessor neural VLSI circuits in the form of a neural network expert system for the identification and classification of measured information fields of sea objects as part of the sea waters monitoring system will provide the ability to solve multi-functional problems of marine science and of the defense industry of the State.

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