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Number of results: 6
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Abstract

This study discriminates different lithological units of the Dokan Area, Kurdistan Region, NE-Iraq, using rapid-eye satellite data by image enhancement techniques, namely the false colour composite (FCC), optimum index factor (OIF), minimum noise fraction (MNF), principal component analysis (PCA) and band ratio (BR). Results of analyses show that the FCC (R: 5; G: 4: B: 1); MNF (R: 2, G: 3, B: 5); PCA (R: 5, G: 2, B: 1), and band ratio (R: 5/4, G: 2/1, B: 5/3) are the best to different geological formations. The results are confirmed in the field support with the geological maps available for the area. Geological formations appeared as a result of the collision process between the Arabian plate and the Iranian plate. In general, the study area is mountainous, which is usually represented by anticline folds with the main NW – SE trend in the study area, with very a rugged relief mainly due to the continuous collision between the Arabian plate and Iranian plate. The digital image processing of satellite data has demonstrated the sensor’s capability and efficiency of the image processing methods in identifying and mapping geological units in the study area.
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Authors and Affiliations

Azhar Kh.S. Bety
1
ORCID: ORCID

  1. University of Sulaimani, College of Science, Department of Geology, Tasluja Str. 1, Zone 501 Sulaimania, As Sulaymaniyah, Kurdistan Region, Iraq
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Abstract

The validation of the measurements quality after on-site diagnostic system installation is necessary in order to provide reliable data and output results. This topic is often neglected or not discussed in detail regarding measurement systems. In the paper recently installed system for soft X-ray measurements is described in introduction. The system is based on multichannel GEM detector and the data is collected and sent in special format to PC unit for further postprocessing. The unique feature of the system is the ability to compute final data based on raw data only. The raw data is selected upon algorithms by FPGA units. The FPGAs are connected to the analog frontend of the system and able to register all of the signals and collect the useful data. The interface used for data streaming is PCIe Gen2 x4 for each FPGA, therefore high throughput of the system is ensured. The paper then discusses the properties of the installation environment of the system and basic functionality mode. New features are described, both in theoretical and practical approach. New modes correspond to the data quality monitoring features implemented for the system, that provide extra information to the postprocessing stage and final algorithms. In the article is described also additional mode to perform hardware simulation of signals in a tokamak-like environment using FPGAs. The summary describes the implemented features of the data quality monitoring features and additional modes of the system.
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Authors and Affiliations

Andrzej Wojenski
1
Paweł Linczuk
1
Piotr Kolasinski
1
Maryna Chernyshova
2
Didier Mazon
3
Grzegorz Kasprowicz
1
Krzysztof T. Pozniak
1
Michał Gaska
1
Tomasz Czarski
2
Rafał Krawczyk
1 4

  1. Warsaw University of Technology, Institute of Electronics Systems, Poland
  2. Institute of Plasma Physics and Laser Microfusion, Warsaw, Poland
  3. CEA, Saint-Paul-lez-Durance, France
  4. CERN, Geneva, Switzerland
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Abstract

In this paper, the performance of Low-Density Parity-Check (LDPC) codes is improved, which leads to reduce the complexity of hard-decision Bit-Flipping (BF) decoding by utilizing the Artificial Spider Algorithm (ASA). The ASA is used to solve the optimization problem of decoding thresholds. Two decoding thresholds are used to flip multiple bits in each round of iteration to reduce the probability of errors and accelerate decoding convergence speed while improving decoding performance. These errors occur every time the bits are flipped. Then, the BF algorithm with a low-complexity optimizer only requires real number operations before iteration and logical operations in each iteration. The ASA is better than the optimized decoding scheme that uses the Particle Swarm Optimization (PSO) algorithm. The proposed scheme can improve the performance of wireless network applications with good proficiency and results. Simulation results show that the ASAbased algorithm for solving highly nonlinear unconstrained problems exhibits fast decoding convergence speed and excellent decoding performance. Thus, it is suitable for applications in broadband wireless networks.
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Authors and Affiliations

Ali Jasim Ghaffoori
1
Wameedh Riyadh Abdul-Adheem
1

  1. Department of Electrical Power Techniques Engineering, AL_Ma’moon University College, Baghdad, Iraq
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Abstract

A revision of the standard approach to characterization of thin-semiconductor-layer Hall samples has been proposed. Our results show that simple checking of I(V) curve linearity at room temperature might be insufficient for correct determination of bias conditions of a sample before measurements of Hall effect. It is caused by the nonlinear behaviour of electrical contact layers, which should be treated together with the tested layer a priori as a metal-semiconductor-metal (MSM) structure. Our approach was examined with a Be-doped p-type InAs epitaxial layer, with four gold contacts. Despite using full high-quality photolithography a significant asymmetry in maximum differential resistance (Rd) values and positions relative to zero voltage (or current) value was observed for different contacts. This suggests that such characterization should be performed before each high-precision magneto-transport measurement in order to optimize the bias conditions.

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Authors and Affiliations

Andrzej Kowalewski
Jarosław Wróbel
Jacek Boguski
Kinga Gorczyca
Piotr Martyniuk
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Abstract

The In this paper stabilisation problem of LC ladder network is established. We studied the following cases: stabilisation by inner

resistance, by velocity feedback and stabilisation by dynamic linear feedback, in particularly stabilisation by first range dynamic feedback. The global asymptotic stability of the respectively system is proved by LaSalle’s theorem. In the proof the observability of the dynamic system plays an essential role. Numerical calculations were made using the Matlab/Simulink program.

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Authors and Affiliations

W. Mitkowski

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