Magnetic reconnection as an element of turbulence

Abstract. In this work, recent advances on the study of reconnection in turbulence are reviewed. Using direct numerical simulations of decaying incompressible two-dimensional magnetohydrodynamics (MHD), it was found that in fully developed turbulence complex processes of reconnection locally occur (Servidio et al., 2009, 2010a). In this complex scenario, reconnection is spontaneous but locally driven by the fields, with the boundary conditions provided by the turbulence. Matching classical turbulence analysis with a generalized Sweet-Parker theory, the statistical features of these multiple-reconnection events have been identified. A discussion on the accuracy of our algorithms is provided, highlighting the necessity of adequate spatial resolution. Applications to the study of solar wind discontinuities are reviewed, comparing simulations to spacecraft observations. New results are shown, studying the time evolution of these local reconnection events. A preliminary study on the comparison between MHD and Hall MHD is reported. Our new approach to the study of reconnection as an element of turbulence has broad applications to space plasmas, shedding a new light on the study of magnetic reconnection in nature.

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Generation of Alfvén wave energy during magnetic reconnection in Hall MHD

Plasma Science and Technology ◽

10.1088/2058-6272/aa7c17 ◽

2017 ◽

Vol 19 (10) ◽

pp. 105001 ◽

Cited By ~ 1

Author(s):

Lingjie LI ◽

Zhiwei MA ◽

Licheng WANG

Keyword(s):

Magnetic Reconnection ◽

Wave Energy ◽

Alfven Wave ◽

Hall Mhd

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Itinerarium Egeriae: A Retrospective Look and Preliminary Study of a New Approach to the Issue of Authorship-provenance

Linguistics and Literature Studies ◽

10.13189/lls.2019.070102 ◽

2019 ◽

Vol 7 (1) ◽

pp. 13-21

Author(s):

Víctor Parra-Guinaldo

Keyword(s):

New Approach ◽

Preliminary Study

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FastPacket: Towards Pre-trained Packets Embedding based on FastText for next-generation NIDS

10.21203/rs.3.rs-555961/v1 ◽

2021 ◽

Author(s):

Khloud Al Jallad

Keyword(s):

Big Data ◽

Deep Learning ◽

Language Processing ◽

Intrusion Detection Systems ◽

Dynamic Feature ◽

Statistical Features ◽

Text Data ◽

New Approach ◽

New Era ◽

Detection Systems

Abstract New Attacks are increasingly used by attackers every day but many of them are not detected by Intrusion Detection Systems as most IDS ignore raw packet information and only care about some basic statistical information extracted from PCAP files. Using networking programs to extract fixed statistical features from packets is good, but may not enough to detect nowadays challenges. We think that it is time to utilize big data and deep learning for automatic dynamic feature extraction from packets. It is time to get inspired by deep learning pre-trained models in computer vision and natural language processing, so security deep learning solutions will have its pre-trained models on big datasets to be used in future researches. In this paper, we proposed a new approach for embedding packets based on character-level embeddings, inspired by FastText success on text data. We called this approach FastPacket. Results are measured on subsets of CIC-IDS-2017 dataset, but we expect promising results on big data pre-trained models. We suggest building pre-trained FastPacket on MAWI big dataset and make it available to community, similar to FastText. To be able to outperform currently used NIDS, to start a new era of packet-level NIDS that can better detect complex attacks

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A study on Electron Oscillations in the Magnetosheath of Mars with Mars Express observations

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317003672 ◽

2016 ◽

Vol 12 (S328) ◽

pp. 230-232

Author(s):

Adriane M. de Souza ◽

Ezequiel Echer ◽

Mauricio J. A. Bolzam ◽

Markus Fränz

Keyword(s):

Wavelet Transform ◽

Electron Density ◽

Low Frequency ◽

Morlet Wavelet ◽

Space Plasmas ◽

Density Data ◽

Mars Express ◽

Preliminary Study ◽

Morlet Wavelet Transform ◽

Low Frequency Waves

AbstractWavelet analysis was employed to identify the major frequencies of low-frequency waves present in the Martian magnetosheath. The Morlet wavelet transform was selected and applied to the electron density data, obtained from the Analyzer of Space Plasmas and Energetic Atoms experiment (ASPERA-3), onboard the Mars Express (MEX) spacecraft. We have selected magnetosheath crossings and analyzed electron density data. From a preliminary study of 502 magnetosheath crossings (observed during the year of 2005), we have found 1409 periods between 0.005 and 0.06Hz. The major frequencies observed were in the range 0.005-0.02 Hz with 58.5% of the 1409 frequencies identified.

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EEG data processing in ADHD diagnosis and neurofeedback

Engineering review ◽

10.30765/er.40.3.12 ◽

2020 ◽

Vol 40 (3) ◽

pp. 116-123

Author(s):

Zoran Šverko ◽

Ivan Markovinović ◽

Miroslav Vrankić ◽

Saša Vlahinić

Keyword(s):

Data Processing ◽

Mean Value ◽

Adhd Group ◽

Eeg Signal ◽

Statistical Features ◽

Eeg Signals ◽

New Approach ◽

Mean Values ◽

Adhd Diagnosis ◽

Eeg Data

In this paper, EEG data processing was conducted in order to define the parameters for neurofeedback. A new survey was conducted based on a brief review of previous research. Two groups of participants were chosen: ADHD (3) and nonADHD (14). The main part of this study includes EEG signal data pre-processing and processing. We have outlined statistical features of observed EEG signals such as mean value, grand-mean value and their ratios. It can be concluded that an increase in grand-mean values of power theta-low beta ratio on Cz electrode gives confirmation of previous research. The value of alpha-delta power ratio higher than 1 on C3, Cz, P3, Pz, P4 in ADHD group is proposed as a new approach to classification. Based on these conclusions we will design a neurofeedback protocol as a continuation of this work.

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Magnetic Reconnection Rate in Space Plasmas: A Fractal Approach

Physical Review Letters ◽

10.1103/physrevlett.99.175002 ◽

2007 ◽

Vol 99 (17) ◽

Cited By ~ 5

Author(s):

Massimo Materassi ◽

Giuseppe Consolini

Keyword(s):

Magnetic Reconnection ◽

Space Plasmas ◽

Reconnection Rate ◽

Fractal Approach

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Non-negative matrix analysis for effective feature extraction in X-ray spectromicroscopy

Faraday Discussions ◽

10.1039/c4fd00023d ◽

2014 ◽

Vol 171 ◽

pp. 357-371 ◽

Cited By ~ 10

Author(s):

Rachel Mak ◽

Mirna Lerotic ◽

Holger Fleckenstein ◽

Stefan Vogt ◽

Stefan M. Wild ◽

...

Keyword(s):

Large Scale ◽

Environmental Science ◽

Matrix Analysis ◽

Matrix Approximation ◽

New Approach ◽

X Ray ◽

Rich Information ◽

Preliminary Study ◽

X Ray Absorption ◽

Calculated Image

X-Ray absorption spectromicroscopy provides rich information on the chemical organization of materials down to the nanoscale. However, interpretation of this information in studies of “natural” materials such as biological or environmental science specimens can be complicated by the complex mixtures of spectroscopically complicated materials present. We describe here the shortcomings that sometimes arise in previously-employed approaches such as cluster analysis, and we present a new approach based on non-negative matrix approximation (NNMA) analysis with both sparseness and cluster-similarity regularizations. In a preliminary study of the large-scale biochemical organization of human spermatozoa, NNMA analysis delivers results that nicely show the major features of spermatozoa with no physically erroneous negative weightings or thicknesses in the calculated image.

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A business process modeling‐based approach to investigate complex processes

Business Process Management Journal ◽

10.1108/14637151211215046 ◽

2012 ◽

Vol 18 (1) ◽

pp. 122-137 ◽

Cited By ~ 5

Author(s):

Faisal A. Abu Rub ◽

Ayman A. Issa

Keyword(s):

Business Process ◽

Process Modeling ◽

Business Processes ◽

Business Process Modeling ◽

New Techniques ◽

New Approach ◽

Content Type ◽

Complex Processes ◽

Model Complex

PurposeThe purpose of this paper is to develop a new approach to investigate complex processes, such as software development processes, using business process modeling.Design/methodology/approachThe paper presents an investigation into the use of role activity diagramming (RAD) to model complex processes in the software industry sector, with reference to the process of TestWarehouse as a case study.FindingsSystematic extension and quantitative analysis to RAD models led to the discovery of process bottlenecks, identification of cross functional boundary problems, and focused discussion about automation of processes.Research limitations/implicationsFurther work is required to validate and evaluate the proposed approach using several cases with different application domains and thus generalize the adopted approach.Practical implicationsA new approach has been used successfully to understand and analyze business processes. The tools and techniques that are used to perform the approach are not complicated and do not need much specialist expertise, so the approach is not only oriented toward specialists but also toward organizations' managers and staff.Originality/valueNew techniques have been developed by using process modelling to deepen the understanding and analyzing of complex organizational processes. This research implements a practical investigation which uses a case study to validate the new techniques.

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