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Chinese Optics Letters 2019年第5期17卷 30-33页

作者： Kuen Yao Lau Pin Jern Ker Ahmad Fauzi Abas mohammed thamer alresheedi Mohd Adzir Mahdi Electronics Research Group. Institute of Power Engineering Uni ver sit i Tenaga Nasional43000 Kajang SelangorMalaysia Department of Electrical Engineering College of EngineeringKing Saud UniversityRiyadh 11421Kingdom of Saudi Arabia Wireless and Photonics Networks Research Centre Faculty of EngineeringUniversiti Putra Alalaysia43400 UPM Ser dangSelangorJMalaysia

A saturable absorber is commonly employed to generate an ultrashort laser with a mode-locking scheme. In an erbium-doped fiber laser system, the laser regimes of either 1530 or 1550 nm wavelength are procured based on the absorption profile of the erbium-doped fiber. The absorption of the erbium-doped fiber is designed to emit at both wavelengths by controlling the net gain of the laser cavity. Subsequently, simultaneous erbium-doped fiber laser emission is attained at 1533.5 and 1555.1 nm with the pulse duration of 910 and 850 fs, ***, this work maximizes the output portfolios of a mode-locking fiber laser for dual-wavelength ultrashort pulses emission.

关键词： mode-locking scheme C-band region dual-wavelength ultrashort pulses emission using

Arsenic Detection Using Surface Plasmon Resonance Sensor With Hydrous Ferric Oxide Layer

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Photonic Sensors 2022年第3期12卷 30-37页

作者： Yasmin MUSTAPHA KAMIL Sura Hmoud AL-REKABI Muhammad Hafiz ABU BAKAR Yap Wing FEN Husam Abduldaem mohammed Nor Hafizah MOHAMED HALIP mohammed thamer alresheedi Mohd Adzir MAHDI inLAZER Dynamics Sdn Bhd InnoHub UnitPutra Science ParkUniversiti Putra MalaysiaSerdang 43400Malaysia Electrical Engineering Department Al Suwayrah Technical InstituteMiddle Technical UniversityBaghdad 10074Iraq Wireless and Photonic Networks Research Centre Faculty of EngineeringUniversiti Putra MalaysiaSerdang 43400Malaysia Institute of Advanced Technology Universiti Putra MalaysiaSerdang 43400Malaysia Department of Physics Faculty of ScienceUniversiti Putra MalaysiaSerdang 43400Malaysia Electronic and Communication Engineering Department College of EngineeringUniversity of BaghdadBaghdad 10071Iraq Department of Electrical Engineering College of EngineeringKing Saud UniversityRiyadh 11421Kingdom of Saudi Arabia

The lethality of inorganic arsenic(As)and the threat it poses have made the development of efficient As detection systems a vital *** research work demonstrates a sensing layer made of hydrous ferric oxide(Fe_(2)H_(2)O_(4))to detect As(Ⅲ)and As(Ⅴ)ions in a surface plasmon resonance *** sensor conceptualizes on the strength of Fe_(2)H_(2)O_(4) to absorb As ions and the interaction of plasmon resonance towards the changes occurring on the sensing *** sensitivity values for As(Ⅲ)and As(Ⅴ)were 1.083°·ppb^(–1) and 0.922°·ppb^(-1),respectively,while the limit of detection for both ions was 0.6 *** findings support the feasibility and potential of the sensor configuration towards paving future advancement in As detection systems.

关键词： Surface plasmon resonance di-iron trioxide hydrate arsenic heavy metals ion optical sensor

Broad bandwidth SOA-based multiwavelength laser incorporating a bidirectional Lyot filter

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Chinese Optics Letters 2018年第9期16卷 22-26页

作者： Abdul Hadi Sulaiman Muhammad Zamzuri Abdul Kadir Nelidya Md Yusoff Noran Azizan Cholan Fairuz Abdullah Ahmad Fauzi Abas mohammed thamer alresheedi Mohd Adzir Mahdi Wireless and Photonic Networks Research Center Faculty of Engineering University Putra Malaysia 43400 UPM Serdang Malaysia Institute of Power Engineering Universiti Tenaga Nasional Jalan IKRAM-UNITEN 43000 Kajang Malaysia Department of Physics Kulliyyah of Science International Islamic University Malaysia 25710 Kuantan Malaysia Razak School of Engineering & Advanced Technology Universiti Teknologi Malaysia Kuala Lumpur Jalan Sultan Yahya Petra 54100 Kuala Lumpur Malaysia Department of Communication Engineering Faculty of Electrical and Electronics Engineering Universiti Tun Hussein Onn Malaysia 86400 Batu Pahat Malaysia Department of Electrical Engineering College of Engineering King Saud University Riyadh 11421 Saudi Arabia

We demonstrate a broad bandwidth multiwavelength laser based on a bidirectional Lyot filter and a semiconductor optical amplifier with a mechanism of intensity-dependent loss as the flatness agent. A wide bandwidth of a multiwavelength spectrum of 32.9 nm within a 5 dB uniformity is obtained under optimized polarization param- eters. For this case, the number of generated lasing lines is 329 with a fixed wavelength separation of 0.1 nm. The power stability of this multiwavelength laser is less than 1.35 dB within 200 min time frame. This shows that the bidirectional Lyot filter provides an alternative option for multiwavelength generation in laser systems.

关键词： SOA Broad bandwidth SOA-based multiwavelength laser incorporating a bidirectional Lyot filter PMF HWP

Filter and Embedded Feature Selection Methods to Meet Big Data Visualization Challenges

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Computers, Materials & Continua 2023年第1期74卷 817-839页

作者： Kamal A.ElDahshan AbdAllah A.AlHabshy Luay thamer mohammed Mathematics Department Faculty of ScienceAl-Azhar UniversityCairo11884Egypt

This study focuses on meeting the challenges of big data visualization by using of data reduction methods based the feature selection *** reduce the volume of big data and minimize model training time(Tt)while maintaining data *** contributed to meeting the challenges of big data visualization using the embedded method based“Select from model(SFM)”method by using“Random forest Importance algorithm(RFI)”and comparing it with the filter method by using“Select percentile(SP)”method based chi square“Chi2”tool for selecting the most important features,which are then fed into a classification process using the logistic regression(LR)algorithm and the k-nearest neighbor(KNN)***,the classification accuracy(AC)performance of LRis also compared to theKNN approach in python on eight data sets to see which method produces the best rating when feature selection methods are ***,the study concluded that the feature selection methods have a significant impact on the analysis and visualization of the data after removing the repetitive data and the data that do not affect the *** making several comparisons,the study suggests(SFMLR)using SFM based on RFI algorithm for feature selection,with LR algorithm for data *** proposal proved its efficacy by comparing its results with recent literature.

关键词： Data Redaction features selection Select from model Select percentile big data visualization data visualization

An Acceptance Model of Using Mobile-Government Services(AMGS)

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Computer Modeling in Engineering & Sciences 2022年第5期131卷 865-880页

作者： Ahmad Althunibat Mohammad Abdallah mohammed Amin Almaiah Nour Alabwaini thamer Ahmad Alrawashdeh Department of Software Engineering Faculty of Science and Information TechnologyAl-Zaytoonah University of JordanAmmanJordan Faculty of Computer Sciences and Information Technology King Faisal UniversityAl-AhsaSaudi Arabia

In recent years,the telecommunications sector is no longer limited to traditional communications,but has become the backbone for the use of data,content and digital applications by individuals,governments and companies to ensure the continuation of economic and social activity in light of social distancing and total closure inmost countries in the ***,electronic government(e-Government)andmobile government(m-Government)are the results of technological evolution and ***,it is important to investigate the factors that influence the intention to use m-Government services among Jordan’s *** paper proposed a new m-Government acceptance model in Jordan(AMGS);this model combines the Information System(IS)Success Factor Model and Hofstede Cultural Dimensions *** study was conducted by surveying different groups of the Jordanian *** questionnaire was used to collect data from203 *** regression analysis has been conducted to analyze the *** results indicate that the significant predictors of citizen intention to use m-Government services in Jordan are Information Quality,Service Quality,Uncertainty Avoidance,and Indulgence ***,the results also suggest that Power Distance is not a significant predictor of citizen intention to use m-Government services.

关键词： Acceptance test e-Government m-Government acceptance model IS success factor model Hofstede cultural dimensions theory

UV-A Activated ZnO Mediated Photocatalytic Decolorization of Nigrosine (Acid Black 2) Dye in Aqueous Solution

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Journal of Geoscience and Environment Protection 2017年第9期5卷 138-147页

作者： mohammed thamer Jaafar Department of Petroleum & Petrochemical Engineering College of Engineering Kerbala University Kerbala Iraq

The present study deals with studied the essential requirements for photo-decoulorization of nigrosine dye with suspension solution of photocatalyst (ZnO), under 250 Watt UV-A light (Io = 1.47 10-7 ensien s-1). A kinetics study of photo-decolourization for this dye was obeyed to pseudo-first order. The best initial pH of decolorization at 25 mg/L of dye solution with 300 mg of ZnO was given a fast reaction at 8.17. The calculated activation energy for this photoreaction was found to be 31.549 kJ·mol-1. Thermodynamically, the reaction is exothermic and spontaneously. The efficiency of decolorizatio E% was 97.077 at 15 min that decreased with addition oxidant reagents such as H2O2, Fe2+ and mixture from them.

关键词： Nigreson Dye Acid Black 2 Dye Photocatalytic Decolorization Oxidant Reagents

Performance Evaluation of Spark Ignited Engine Fueled with Gasoline-Ethanol-Methanol Blends

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Journal of Energy and Power Engineering 2016年第6期10卷 343-351页

作者： mohammed Kamil Ibrahim thamer Nazzal Mechanical Engineering Department University of Sharjah Sharjah 27272 UAE Mechanical Engineering Department Graduate School of Engineering Ozyegin University Istanbu10090 Turkey

In this paper, experimental investigations are presented to assess the performance variations in a single cylinder spark ignited engine when run with three different gasoline-alcohol blends：（88% gasoline-12% methanol, 88% gasoline-12% ethanol and 88% gasoline-6% methanol-6% ethanol）. Additional tests are carried out with the basic gasoline fuel for comparison analysis and performance assessment. Engine performance is investigated under a variety of engine operating conditions. The results are presented in the domain of engine speed. In particular, the brake power of the engine is shown to be slightly increased. The brake thermal efficiency showed an increase compared with the basic gasoline engine. Similarly, it is shown that brake specific fuel consumption is enhanced compared with basic gasoline engine. The exhaust gas temperature showed a decrease compared with gasoline fuel which is preferable to reduce emissions. The alcohol additives are strongly recommended to enhance performance, increasing the mileage and reducing the emissions.

关键词： Gasoline performance ethanol methanol SI engine blends.

Mechanism of Building-Up Deposited Layer during Electro-Spark Deposition

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Journal of Surface Engineered Materials and Advanced Technology 2012年第4期2卷 258-263页

作者： Amin D. thamer mohammed H. Hafiz Baha S. Mahdi Dean of Material Engineering Dept. Baghdad Iraq Lacturer in Production & Metallurgical Eng. Dept. Baghdad Iraq Prisedent of University of Tehchnology Baghdad Iraq

This paper studies the mechanism of formation of the deposit layer by (ESD) electro-spark deposition process. Inconel 738 substrates are coated with a deposited layer of NI6625 (Inconel 625). Selections of these two alloys have been done because they had wide applications and importance in the industry especially in gas turban blades in inland stations and in aircraft engines. ESD is suggested because it has a low input heat process which eliminates the effect of HAZ in these Ni-superfluous due to their sustainability to micro-cracks. The coating contains many deposited sub-layers coming from evaporated and melted micro-regions as a result of locally high heat generated by discharging a series of capacitors charged and discharged in a controlled manner between electrode and substrate material. The maximum deposition rates at the beginning of the process and decreases until been in a steady state condition due to the nature of the resultant morphology of the created surface.

关键词： ESD ESA Electro-Spark Deposition IN738L Repairing NI6625 Surface Repairing of Gas Turbine Blades

Influence of Atmospheric Non-thermal Plasma on Some Hematological Characteristics of Iraqi Patients

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Journal of Physical Science and Application 2016年第1期6卷 82-87页

作者： thamer Hameid mohammed Ubaid Hussein Abdul Rahman M. G. A1-Fahdawi Department of Physics College of Science Baghdad University Baghdad Iraq Department of physiology and medieal physics College of Medicine Anbar University Anbar Iraq Department of Anatomy and Histology College of Medicine Anbar University Anbar Iraq

Non-thermal atmospheric pressure plasma has emerged as a new promising tool in medicine. The effectiveness of an Atmospheric Non Thermal Plasma for clinical and biological applications is studied. This research effort includes a desioning of plasma generating system and examine it on some medical and biological parameters. No patient had previous operative or chemotherapeutic treatment, so the patients with hematological disorders （hemophilia） and those with open heart surgery that receiving warfarin and other antithrombotic agents were excluded from the study. A total of eighty 80 Iraqi patients seeking for a medical consultation in A1-Ramadi Teaching Hospital were included in this study. The plasma treatment is applied both in vitro and in vivo experiments on those patients. In the in vivo experiments, the bleeding time tests were carried out on these patients; the results showed the bleeding time of the patients was reduced as compared with control. In vitro experiments regarding clotting time and prothrombine time PT, the results have demonstrated that this plasma device clots blood rapidly via a control. The dependencies of the degree of clotting on the exposure time, distance have been recorded. A series of experiments reveal that this effectiveness is due to the ability of direct discharge to bring charges to blood samples due to generation of so many mediators like reactive nitrogen species and free radicals.

关键词： Atmospheric non-thermal plasma bleeding time clotting time prothermbine time.

Awareness and Behaviour Related to Orthodontic Treatment among School Children in Aseer Region, Kingdom of Saudi Arabia

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Open Journal of Stomatology 2019年第4期9卷 87-94页

作者： M. Zakirulla Hussain Almubarak Sahar N. Fageeh Abeer A. Alghothimi Saleh Khalid Alqahtani Faris mohammed Alqahtani Fahad thamer Alshahrani Department of Pediatric Dentistry and Orthodontic Sciences College of Dentistry King Khalid University Abha KSA Department of the Diagnostic Science and Oral Biology (DDS) College of Dentistry King Khalid University Abha KSA

Background: Awareness of malocclusion and the need to make corrections have increasingly become prevalent among the young population. In the period of adolescence, physical appearance is crucial in the construction of personal identity, including one’s relationship with one’s own body. Orthodontic treatment includes improved oral health and enhanced psychological wellbeing. Early orthodontic treatment for children will be crucial to improving oral health. The present study aims to assess the awareness towards orthodontic treatment among school children’s of Aseer region, Saudi Arabia. Materials and Methods: A total of 835 (450 boys and 385 girls) school children’s, of age group between 10 - 15 years were included in the study. A total of 16 schools in the all Aseer region were surveyed during January to May 2018. A pre-structured self-administered questionnaire consisting of 12 questions with multiple answers were given to the children after the clinical examination to assess their knowledge and attitude towards Orthodontic treatment. Statistical Analysis: The survey data was collected and organized into Microsoft Excel spreadsheets (Microsoft Inc., USA), and was statistically analyzed utilizing the Statistical Package for the Social Sciences version 20.0 software (IBM Inc., USA). The statistical test used here was the chi-square test and P values less than 0.05 were considered to be statistically significant (P Result: A total of 292 (65%) of males and 285 (74%) of females have heard of an orthodontist. 234 (52%) of males said that orthodontist would align their teeth. 203 (45%) and 250 (65%) of males and females respectively are aware that few teeth needed to be removed for aligning irregular teeth. Majority of the children are aware of taking braces treatment at an earlier age would improve facial appearance. 320 (83%) and 227 (59%) of female children aware of that irregular teeth can affect chewing ability and speech respectively. 261 (58%) of males knew that or

关键词： Orthodontic Treatment Malocclusion Children Oral Health Behaviour