2

Year: 2024

Academic Degree: Master

Supervisor Type: Co-supervisor

Supervisor State: In Progress

Musa Anwar, my second graduate student

1

Year: 2023

Academic Degree: Master

Supervisor Type: Supervisor

Supervisor State: In Progress

Hiyam Jumaa Qadir, my first graduate student.

Bachelor of Science

Oct 1, 2003 - Jun 30, 2007

Bachelor of Science degree in Electronics and Control Engineering Techniques

Master of Science

Oct 16, 2010 - May 11, 2012

Master of Science degree in Telecommunication Engineering

Doctor of Philosophy

Jan 25, 2015 - May 10, 2019

PhD in Communications Engineering and Information Theory

Instructor [Lab Instructor]

May 12, 2008 - Jul 24, 2010

Lab Instructor at the labs of the Technical Engineering College-Kirkuk

Research [Research assistant]

Sep 15, 2010 - May 1, 2012

Research assistant at the University of Mississippi 2010-2012.

Lecturer [Faculty member and lecturer]

Jul 1, 2012 - Jan 15, 2015

Faculty member and lecturer at the Technical Engineering College-Kirkuk 2012 -2015.

Lecturer [Lecturer, research assistant, and teaching assistant]

Jan 26, 2015 - May 1, 2019

Lecturer, research assistant, and teaching assistant at the University of Mississippi 2015 - 2019.

Lecturer [Faculty member and lecturer]

Jun 3, 2015 - Present

Faculty member and lecturer at the Technical Engineering College of Kirkuk-NTU 2019-present.

A Semantic Metadata Framework for Enhanced Accounting Information Systems Design, Implementation, and Performance Analysis

May 15, 2025

Journal CIC-ISCAFS'2025

DOI https://doi.org/10.24086/icafs2025/paper.1740

This paper presents a new way of using semantic metadata for accounting information systems that enriches financial transactions with context of business information. The framework has a four-layer architecture consisting of base transaction layer, business context layer, relationship layer, and compliance layer. This framework helps to capture and use the context of business in accounting. Our framework is practically validated based on JSON-LD implementation and extensive simulation tests. The simulation in our paper, which consisted of one million transactions, yielded a query response time of 5.9 milliseconds with 100% consistency. The system's continuous processing rate was 44 transactions per second (TPS) with cache usage efficiency being 71.05%. The findings show that practical performance characteristics can be maintained in accounting systems despite semantic metadata integration. The framework allows for enhanced business intelligence, automated compliance checking, and improved decision support in accounting systems. Our tests demonstrate that semantic details can be seamlessly incorporated into classic accounting practices without hindering the performance of the system or losing data. Keywords— Semantic metadata, Accounting information systems, Business context, Data integrity, Performance analysis.

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Low Complexity Subcarrier Activation Scheme for OFDM with Index Modulation

Dec 23, 2024

Journal Radioelectronics and Communications Systems

DOI https://doi.org/10.3103/S0735272724020018

Issue 1

Volume 67

In orthogonal frequency division multiplexing with index modulation (OFDM-IM), data is mapped to subcarrier activation patterns (SAP) using look-up tables or combinatorial schemes. The complexity of these mapping schemes increases with the number of subcarriers. Therefore, they are applied to subgroups of subcarriers, but unfortunately, at the expense of reducing the amount of data loaded to an OFDM block. In this paper, low-complexity direct data to SAP mapping is proposed, the necessary analysis to determine the analytical bit error rate (BER) is presented, and the computer simulations are performed to find and compare theoretical and simulated BER results under conditions of the frequency selective Rayleigh fading channel. The proposed scheme can load more data bits to an OFDM block than conventional schemes. The results from computer simulations demonstrate the superiority of the OFDM-IM system using the proposed scheme over conventional OFDM-IM in terms of BER performance.

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Novel methods to measure the quality of 2d images compression techniques

Mar 23, 2023

DOI https://doi.org/10.21203/rs.3.rs-2629953/v1

It is essential to use image quality measuring metrics tools that can provide accurate and close to perceived quality sense of the tested images. Such tools give metrics that can be used to compare the performance of compression algorithms. In this paper, two new metrics to measure the quality of decompressed images are proposed. Compared with other metrics eg peak signal to noise ratio (PSNR) and root mean square error (RMSE), the proposed metrics give values with the closest reflection of image quality perception by the human eye.

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Automatic PV Array Reconfiguration under Partial Shading Conditions

Mar 10, 2023

Journal NTU Journal of Renewable Energy

publisher MDPI

DOI https://doi.org/10.56286/ntujre.v4i1.413

Issue 1

Volume 4

Photovoltaic (PV) arrays have been recognized as one of the main clean renewable sources of electrical energy. In practice, PV arrays are subject to unavoidable non-uniform partial shading (PS) due to clouds, buildings, dust, etc. PS causes the hot spot problem, mismatch losses, and output power degradation. A widely used approach to mitigate the effect of PS is dynamic reconfiguration, where, the interconnection of PV panels is modified according to the shading condition to achieve maximum output. Dynamic reconfiguration techniques use sensors, a programmable controller, and a switch matrix for optimal operation. However, they have drawbacks such as system complexity and scalability issues. For instance, reducing the number of switches limits the flexibility of the reconfiguration algorithm. In this paper, an automatic dynamic reconfiguration scheme is proposed in which PV panel irradiation activity controls the interconnection of switches, without the need for a programmable controller. A modular building block is proposed from which easily scalable PV arrays can be constructed in a hierarchical manner. Experimental and analytic results have verified the effectiveness of the proposed reconfiguration scheme.

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Automatic PV array reconfiguration under partial shading conditions

Feb 10, 2023

Journal NTU Journal of Renewable Energy

publisher IENorthern Technical UniversityEE

DOI https://doi.org/10.56286/ntujre.v4i1.413

Issue 1

Volume 4

Photovoltaic (PV) arrays have been recognized as one of the main clean renewable sources of electrical energy. In practice, PV arrays are subject to unavoidable non-uniform partial shading (PS) due to clouds, buildings, dust, etc. PS causes the hot spot problem, mismatch losses, and output power degradation. A widely used approach to mitigate the effect of PS is dynamic reconfiguration, where, the interconnection of PV panels is modified according to the shading condition to achieve maximum output. Dynamic reconfiguration techniques use sensors, a programmable controller, and a switch matrix for optimal operation. However, they have drawbacks such as system complexity and scalability issues. For instance, reducing the number of switches limits the flexibility of the reconfiguration algorithm. In this paper, an automatic dynamic reconfiguration scheme is proposed in which PV panel irradiation activity controls the interconnection of switches, without the need for a programmable controller. A modular building block is proposed from which easily scalable PV arrays can be constructed in a hierarchical manner. Experimental and analytic results have verified the effectiveness of the proposed reconfiguration scheme.

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Detection and diagnosis of stator and rotor electrical faults for three-phase induction motor via wavelet energy approach

Apr 15, 2022

Journal Electronics

publisher MDPI

DOI https://doi.org/10.3390/electronics11081253

Issue 8

Volume 11

This paper presents a fault detection method in three-phase induction motors using Wavelet Packet Transform (WPT). The proposed algorithm takes a frame of samples from the three-phase supply current of an induction motor. The three phase current samples are then combined to generate a single current signal by computing the Root Mean Square (RMS) value of the three phase current samples at each time stamp. The resulting current samples are then divided into windows of 64 samples. Each resulting window of samples is then processed separately. The proposed algorithm uses two methods to create window samples, which are called non-overlapping window samples and moving/overlapping window samples. Non-overlapping window samples are created by simply dividing the current samples into windows of 64 samples, while the moving window samples are generated by taking the first 64 current samples, and then the consequent moving window samples are generated by moving the window across the current samples by one sample each time. The new window of samples consists of the last 63 samples of the previous window and one new sample. The overlapping method reduces the fault detection time to a single sample accuracy. However, it is computationally more expensive than the non-overlapping method and requires more computer memory. The resulting window samples are separately processed as follows: The proposed algorithm performs two level WPT on each resulting window samples, dividing its coefficients into its four wavelet subbands. Information in wavelet high frequency subbands is then used for fault detection and activating the trip signal to disconnect the motor from the power supply. The proposed algorithm was first implemented in the MATLAB platform, and the Entropy power Energy (EE) of the high frequency WPT subbands’ coefficients was used to determine the condition of the motor. If the induction motor is faulty, the algorithm proceeds to identify the type of the fault. An empirical setup of the proposed system was then implemented, and the proposed algorithm condition was tested under real, where different faults were practically induced to the induction motor. Experimental results confirmed the effectiveness of the proposed technique. To generalize the proposed method, the experiment was repeated on different types of induction motors with different working ages and with different power ratings. Experimental results show that the capability of the proposed method is independent of the types of motors used and their ages.

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Look-up Table Reduction for Subcarrier Activation in OFDM with Index Modulation Systems

Jan 26, 2022

Journal IMDC-IST 2021

publisher EUDL

DOI http://dx.doi.org/10.4108/eai.7-9-2021.2314821

Orthogonal frequency division multiplexing with index modulation (OFDMIM) is a promising multi-carrier communication technique. A limited set of k out of n available subcarriers are activated and modulated by constellation symbols. The selection of the subcarrier activation pattern is performed according to data mapped via Look-up Tables (LUTs) or equivalent iterative mathematical algorithms. The complexity of mapping data to active subcarrier indices can rise dramatically with n, and then limit the applicability of OFDM-IM. Therefore, in this paper, a new subcarrier activation scheme is proposed, where smaller size LUTs are used. A reduction ratio in LUT overall size of about 84% is achieved for (𝑛, 𝑘)=(8, 4), and this ratio increases with n. The presented analysis and simulation show that an OFDM-IM exploiting the proposed scheme is an identical less complex version of classical OFDM-IM, with a very close BER performance.

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Flyback Photovoltaic Micro-Inverter with a Low Cost and Simple Digital-Analog Control Scheme

Jul 14, 2021

Journal Energies

publisher MDPI

DOI https://doi.org/10.3390/en14144239

Issue 14

Volume 14

The single-stage flyback Photovoltaic (PV) micro-inverter is considered as a simple and small in size topology but requires expensive digital microcontrollers such as Field-Programmable Gate Array (FPGA) or Digital Signal Processor (DSP) to increase the system efficiency, this would increase the cost of the overall system. To solve this problem, based on a single-stage flyback structure, this paper proposed a low cost and simple analog-digital control scheme. This control scheme is implemented using a low cost ATMega microcontroller built in the Arduino Uno board and some analog operational amplifiers. First, the single-stage flyback topology is analyzed theoretically and then the design consideration is obtained. Second, a 120 W prototype was developed in the laboratory to validate the proposed control. To prove the effectiveness of this control, we compared the cost price, overall system efficiency, and THD values of the proposed results with the results obtained by the literature. So, a low system component, single power stage, cheap control scheme, and decent efficiency are achieved by the proposed system. Finally, the experimental results present that the proposed system has a maximum efficiency of 91%, with good values of the total harmonic distortion (THD) compared to the results of other authors.

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Performance of raptor codes on the BIAWGN channel in the presence of SNR mismatch

May 25, 2020

Journal WCNC

publisher IEEE

DOI https://doi.org/10.1109/WCNC45663.2020.9120480

Accurate estimation of the channel signal to noise ratio (SNR) is essential for belief propagation (BP) decoding to operate optimally. Incorrect estimation of the channel SNR is known as SNR mismatch and can lead to serious degradation in BP decoding performance especially when a code is operating near its decoding threshold. We analyze the asymptotic performance of Raptor codes under SNR mismatch on the binary input additive white Gaussian noise (BIAWGN) channel using discretized density evolution (DDE). We provide the decoding thresholds of Raptor codes for a wide range of SNR mismatch values. Our results show that overestimation of channel SNR is slightly more detrimental than underestimation for lower levels of SNR mismatch, while, underestimation becomes more detrimental as the mismatch increases. Finally, we use DDE-based optimization to design SNR mismatch tolerant output degree …

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Raptor Codes for BIAWGN Channel: SNR Mismatch and the Optimality of the Inner and Outer Rates

Sep 23, 2019

publisher University of Mississippi

DOI https://doi.org/10.1109/GlobalSIP.2015.7418204

Fountain codes are a class of rateless codes with two interesting properties, first, they can generate potentially limitless numbers of encoded symbols given a finite set of source symbols, and second, the source symbols can be recovered from any subset of encoded symbols with cardinality greater than the number of source symbols. Raptor codes are the first implementation of fountain codes with linear complexity and vanishing error floors on noisy channels. Raptor codes are designed by the serial concatenation of an inner Luby trans-form (LT) code, the first practical realization of fountain codes, and an outer low-density parity-check (LDPC) code. Raptor codes were designed to operate on the binary erasure channel (BEC), however, since their invention they received considerable attention in or-der to improve their performance on noisy channels, and especially additive white Gaussiannoise (AWGN) channels. This dissertation considers two issues that face Raptor codes on the binary input additive white Gaussian noise (BIAWGN) channel: inaccurate estimation of signal to noise ratio (SNR) and the optimality of inner and outer rates. First, for codes that use a belief propagation algorithm (BPA) in decoding, such as Raptor codes on the BIAWGN channel, accurate estimation of the channel SNR is crucial to achieving optimal performance by the decoder. A difference between the estimated SNR and the actual channel SNR is known as signal to noise ratio mismatch (SNRM). Using asymptomatic analysis and simulation, we show the degrading effects of SNRM on Raptor codes and observe that if the mismatch is large enough, it can cause the decoding to fail. Using the discretized density evolution (DDE) algorithm with the modifications required to simulate the asymptotic performance in the case of SNRM, we determine the decoding threshold of Raptor codes for different values of SNRM ratio. Determining the threshold under SNRM enables us to quantify its effects which in turn can be used to reach important conclusions about the effects of SNRM on Raptor codes. Also, it can be used to compare Raptor codes with different designs in terms of their tolerance to SNRM. Based on the threshold response to SNRM, we observe that SNR underestimation is slightly less detrimental to Raptor codes than SNR overestimation for lower levels of mismatch ratio, however, as the mismatch increases, underestimation becomes more detrimental. Further, it can help estimate the tolerance of a Raptor code, with certain code parameters when transmitted at some SNR value, to SNRM. Or equivalently, help estimate the SNR needed for a given code to achieve a certain level of tolerance to SNRM. Using our observations about the performance of Raptor codes under SNRM, we propose an optimization method to design output degree distributions of the LT part that can be used to construct Raptor codes with more tolerance to high levels of SNRM. Second, we study the effects of choosing different values of inner and outer code rate pairs on the decoding threshold and performance of Raptor codes on the BIAWGN channel. For concatenated codes such as Raptor codes, given any instance of the overall code rate R, different inner (Ri) and outer (Ro) code rate combinations can be used to share the available redundancy as long asR=RiRo. Determining the optimal inner and outer rate pair can improve the threshold and performance of Raptor codes. Using asymptotic analysis, we show the effect of the rate pair choice on the threshold of Raptor codes on the BIAWGN channel and how the optimal rate pair is decided. We also show that Raptor codes with different output degree distributions can have different optimal rate pairs, therefore, by identifying the optimal rate pair we can further improve the performance and avoid suboptimal use of the code. We make the observation that as the outer rate of Raptor codes increases the potential of achieving better threshold increases, and provide the reason why the optimal outer rate of Raptor codes cannot occur at lower values. Finally, we present an optimization method that considers the optimality of the inner and outer rates in designing the output degree distribution of the inner LT part of Raptor codes. The designed distributions show improvement in both the decoding threshold and performance compared to other code designs that do not consider the optimality of the inner and outer rates.

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On unequal error protection raptor codes

Dec 14, 2015

Journal GlobalSIP

publisher IEEE

DOI https://doi.org/10.1109/GlobalSIP.2015.7418204

Raptor codes are the most advanced fountain codes that can provide dynamically changeable code rate and have linear time encoding and decoding. In multimedia communications and different other areas, it is desired that channel codes can provide the property of unequal error protection (UEP). In this paper, we study two methods to provide UEP Raptor codes on the binary erasure channel (BEC): (1) Using UEP precode (2) Using UEP LT codes. With analysis and thorough simulation we compare the two methods and we conclude that applying UEP in the precode can achieve lower bit erasure rate (BER) for both the more important bits (MIB) and less important bits (LIB).

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Look-up Table Reduction for Subcarrier Activation in OFDM with Index Modulation Systems

Sep 7, 2021 - Sep 9, 2021

Publisher EAI

DOI http://dx.doi.org/10.4108/eai.7-9-2021.2314821

Country Turkey

Location Sakarya

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Performance of Raptor Codes on the BIAWGN Channel in the Presence of SNR Mismatch

Jun 19, 2020 - Jun 20, 2020

DOI https://doi.org/10.1109/WCNC45663.2020.9120480

Country Korea (South)

Location Seoul

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2015 IEEE Global Conference on Signal and Information Processing (GlobalSIP)

Dec 14, 2016 - Dec 16, 2016

Publisher IEEE

DOI https://doi.org/10.1109/GlobalSIP.2015.7418204

Country USA

Location Orlando, FL

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