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Cross-Domain Transfer Learning For Domain Adaptation In Autism Spectrum Disorder Diagnosis, Kush Gupta, Amir Aly, Emmanuel Ifeachor Jan 2025

Cross-Domain Transfer Learning For Domain Adaptation In Autism Spectrum Disorder Diagnosis, Kush Gupta, Amir Aly, Emmanuel Ifeachor

School of Engineering, Computing and Mathematics

A cross-domain transfer learning approach is introduced to address the challenges of diagnosing individuals with Autism Spectrum Disorder (ASD) using small-scale fMRI datasets. Vision Transformer (ViT) and TinyViT models pre-trained on the ImageNet, were employed to transfer knowledge from the natural image domain to the brain imaging domain. The models were fine-tuned on ABIDE and CMI-HBN, using a teacher student framework with knowledge distillation loss. Experimental results demonstrated that our method outperformed previous studies, ViT models, and CNN-based models. Our approach achieved competitive performance (F-1 score 78.72%) with a much smaller parameter size. This study highlights the effectiveness of cross-domain …

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Acquiring Ethical Ai, David S. Rubenstein Jan 2025

Acquiring Ethical Ai, David S. Rubenstein

Florida Law Review

Artificial intelligence (AI) is transforming how the federal government operates. Under the right conditions, AI systems can solve complex problems, reduce administrative burdens, improve human decisions, and optimize resources. Under the wrong conditions, AI systems can lead to widespread discrimination, invasions of privacy, and the erosion of democratic norms. A burgeoning literature has emerged to square algorithmic governance with the precepts of constitutional and administrative law. Federal procurement law, however, remains a dangerous blind spot in the reformist agenda. This Article pivots into that neglected space and emerges with comprehensive framework for acquiring ethical AI. Toward that end, the Article …

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Optimization Of The Cross-Section Of Generic Flexible Bridges, Manal Kamal Zaki, Mina M. Helmy, Mark M. Tawadros Jan 2025

Optimization Of The Cross-Section Of Generic Flexible Bridges, Manal Kamal Zaki, Mina M. Helmy, Mark M. Tawadros

Journal of Engineering Research

This paper investigates the behavior of flexible bridges prone to aerodynamic instabilities due to wind. Optimal cross-sections that reduce aerodynamic forces are recommended. This is achieved by studying a variety of bridge sections with different widths of upper and lower sloping edges in addition to studying the upper and lower cramps of the deck. The wind velocities are also parameterized. Computations are developed based on the powerful computational fluid dynamics (CFD) method known as FLUENT and embedded in ANSYS software. For parametric study, a design of experiments (DOE) is performed based on the response surface methodology (RSM) combined with the …

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Enhancing Efficiency In Cyclone Separators: Insights From Triangular Finned Structures And Fluid Dynamics Analysis, Ibrahim M. Mohamed, Yasser El-Shaer, Khairy Elsayed, Mohamed Aly Ibrahim Jan 2025

Enhancing Efficiency In Cyclone Separators: Insights From Triangular Finned Structures And Fluid Dynamics Analysis, Ibrahim M. Mohamed, Yasser El-Shaer, Khairy Elsayed, Mohamed Aly Ibrahim

Journal of Engineering Research

Cyclone separators play a pivotal role in removing particulate matter from gas streams. These elegant devices find applications across diverse industries, including cement production, petroleum refineries, and food processing. This computational study focuses on the effects of adding fined surfaces to the cylindrical part of cyclone separators on the flow field and the performance parameters. Different fins are used at different depths, namely, 0.004 m, 0.008 m, 0.01 m, different pitches, namely, 0.025 m, 0.04 m, 0.05 m and different helix lengths, namely, 0.2 m, 0.25 m, 0.3 m. The results indicated that optimal fin adhesion reduces the pressure drop, …

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Simultaneous Optimal Sizing And Placement Of Electrical Vehicles Charging Stations And Distributed Generation Units In Electrical Distribution Networks Using Abc Technique, Abdelazim M. Salem Dr., Nora M. El-Ayaat, Ismail M. Hafez Prof., Adel Abou El Ela Prof. Jan 2025

Simultaneous Optimal Sizing And Placement Of Electrical Vehicles Charging Stations And Distributed Generation Units In Electrical Distribution Networks Using Abc Technique, Abdelazim M. Salem Dr., Nora M. El-Ayaat, Ismail M. Hafez Prof., Adel Abou El Ela Prof.

Journal of Engineering Research

The continuous increment in the utilization of electric vehicles (EV’s) that represent new loads on the electrical distribution networks. The distributed generators (DG’s) have been used in the distribution networks as renewable energy sources (RES) with the main electrical distribution network for supplying significant amount of the total connected loads. The using of DG’s lead to reduce the electrical active power losses and improving the voltage profile on the distribution network. A well-planned and efficient EV’s charging infrastructure is required for effective electric mobility. This paper presents a planning study for supplying up to four EVCS’s, each one increases the …

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Dwellings Occupant Behaviour And Electric Heating Consumption: Sensitivity Analysis And Potential Savings, Youssef Elkhayat Jan 2025

Dwellings Occupant Behaviour And Electric Heating Consumption: Sensitivity Analysis And Potential Savings, Youssef Elkhayat

Journal of Engineering Research

A building's heating consumption is affected by a lot of things, including the weather, the building's envelope, and the heating system. Furthermore, a crucial component impacting dwelling electrical consumption is the behaviour of occupants. Analysing the impact of occupant behaviour on electric heating consumption in dwellings located in temperate oceanic climates is the focus of this study. By surveying the existing literature on the topics of building energy simulation and occupant behaviour, this study was able to determine the strengths and weaknesses of earlier investigations, as well as the research technique. A case study of a semi-detached house in Galway, …

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Using Nanotechnology To Achieve Sustainability In Interior Residential Spaces, Neveen Youssef Azmy, Esraa Tarek Abu-El Azm, Ahmed Ahmed Rizk, Walaa Abou El-Haggag Mehanna Jan 2025

Using Nanotechnology To Achieve Sustainability In Interior Residential Spaces, Neveen Youssef Azmy, Esraa Tarek Abu-El Azm, Ahmed Ahmed Rizk, Walaa Abou El-Haggag Mehanna

Journal of Engineering Research

Major scientific and technological developments characterize the present time. One notable achievement is the nano revolution, which has greatly influenced various areas of life Nanotechnology is characterized by using very small particles of materials, either alone or by processing them to create new materials with remarkable properties. Hence, nanotechnology offers promising economic solutions and products to achieve a reliable and sustainable environment. Architecture has great potential to benefit from this technology to achieve sustainability and improve indoor environment quality. Given the proliferation of residential buildings in urban areas, where people spend most of their time, it is necessary to integrate …

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Evaluating Lidar Technology In Iphone Mobiles For 2d Mapping Applications, Nasr Mohammady Saba, Salem Salama Saleh Jan 2025

Evaluating Lidar Technology In Iphone Mobiles For 2d Mapping Applications, Nasr Mohammady Saba, Salem Salama Saleh

Journal of Engineering Research

Abstract- LiDAR (Light Detection and Ranging) technology has revolutionized mapping applications, offering enhanced precision and accuracy in spatial data collection. The integration of LiDAR technology in the latest iPhone models, beginning with the iPhone 12 Pro, has introduced new capabilities for 2D data measurement and plan creation directly on the mobile device. The iPhone 12 Pro and 12 Pro Max models support LiDAR techniques within their mobile phone cameras, enhancing the performance of various applications such as Measurements and Photos. LiDAR operates by emitting pulsed light waves into the surrounding space, which bounce off nearby objects and return to the …

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Experimental And Numerical Investigation For Optimum Design Of Hydraulic Steel Gates, Basma Hassan Mohamed Eng, Ahmed Mohamed Anwer Dr, Hanan Eltobgy Prof., Gamal Helmy El-Saeed Prof Jan 2025

Experimental And Numerical Investigation For Optimum Design Of Hydraulic Steel Gates, Basma Hassan Mohamed Eng, Ahmed Mohamed Anwer Dr, Hanan Eltobgy Prof., Gamal Helmy El-Saeed Prof

Journal of Engineering Research

Conventionally, steel gates are widely used in hydraulic structures for their superior mechanical properties in sustaining hydrostatic pressure. Maintenance and operational costs should be considered while studying the feasibility of these gates. In the current research, three prototype steel gates with different configurations were prepared and examined experimentally. The three gates have the same surface dimensions of (width x height) equal to (1.0 x 1.25 m). The first steel gate represents a typical traditional gate made of skin plate and stiffened laterally using standard steel channels and will be kept for comparison. The second gate represents a standard thicker plate …

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Performance And Emissions Characteristics Of Multi-Cylinder Direct Injection Diesel Engine Fuelled With Diesel/Biodiesel And Toluene Additives, Hagar Alm-Eldin Bastawissi, Medhat Elkelawy Prof. Dr. Eng., Mohammed Osama Elsamadony Dr. Eng., Moustafa Ghazaly Eng. Jan 2025

Performance And Emissions Characteristics Of Multi-Cylinder Direct Injection Diesel Engine Fuelled With Diesel/Biodiesel And Toluene Additives, Hagar Alm-Eldin Bastawissi, Medhat Elkelawy Prof. Dr. Eng., Mohammed Osama Elsamadony Dr. Eng., Moustafa Ghazaly Eng.

Journal of Engineering Research

This study explores the impact of using a diesel, biodiesel, and toluene additive fuel blend in a multi-cylinder direct injection diesel engine, focusing on both performance and emissions characteristics. Biodiesel, made from renewable sources like vegetable oils, is often added to diesel to reduce reliance on fossil fuels and improve combustion due to its higher oxygen content. In this work, a 45% biodiesel blend (B45) led to significant reductions in particulate matter (PM) emissions by up to 40% compared to conventional diesel. Additionally, carbon monoxide (CO) and hydrocarbon (HC) emissions decreased by up to 30% and 25%, respectively, due to …

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Effect Of Dual-Fuelled Cng And Gasoline On Spark Ignition Engine Performance And Emissions Behaviors At Different Loads, Medhat Elkelawy Prof. Dr, Eng., M.M. Bassuoni Prof. Dr., Hagar Alm-Eldin Bastawissi, Saied I. Haiba Eng. Jan 2025

Effect Of Dual-Fuelled Cng And Gasoline On Spark Ignition Engine Performance And Emissions Behaviors At Different Loads, Medhat Elkelawy Prof. Dr, Eng., M.M. Bassuoni Prof. Dr., Hagar Alm-Eldin Bastawissi, Saied I. Haiba Eng.

Journal of Engineering Research

Engine emissions are one of numerous factors that have detrimentally affected the environment, such as global warming, which is the result of growing exhaust gases, practically carbon dioxide (CO2). These emissions have substantially influenced researchers to develop strategic initiatives to minimize the carbon contents of fuels. The purpose of this research is to investigate the characteristics of internal combustion (SI) engines fueled by gasoline and compressed natural gas (CNG) blends. The experiments are performed using a HONDA 4-stroke, single-cylinder, and air-cooled SI engine. Five CNG concentrations are evaluated, the concentrations range from 0.5 to 2.5 L/min with a 0.5 L/min …

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A Quantitative Analysis Of The Commercial-Additive Effects On Diesel Engine Combustion And Emissions Characteristics, Medhat Elkelawy Prof. Dr. Eng., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Mahmoud Mohamed Soliman Mahmoud Mohamed Mahmoud Soliman Jan 2025

A Quantitative Analysis Of The Commercial-Additive Effects On Diesel Engine Combustion And Emissions Characteristics, Medhat Elkelawy Prof. Dr. Eng., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Mahmoud Mohamed Soliman Mahmoud Mohamed Mahmoud Soliman

Journal of Engineering Research

Petroleum fuel prices fluctuate in response to global political and economic issues. Government regulations should be followed when it comes to engine emissions, as these dangerous pollutants have a negative impact on the environment. One such effect is global warming, which raises global temperatures. The purpose of this study is to develop the additives for use as a fuel mix with diesel fuel, which will be used to feed the diesel engine of a single cylinder, four strokes. The engine will be tested experimentally with varying loads at fixed speed of 1500 rpm, using blends of [(5% PRETSONE additive + …

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Design And Implementation Of A Low-Cost Educa-Tional Robot For Engineering Curriculums, Diana Refaat Henry Jacob, Ashraf Mohamed Hafez, Mohamed Tarek Elawa Jan 2025

Design And Implementation Of A Low-Cost Educa-Tional Robot For Engineering Curriculums, Diana Refaat Henry Jacob, Ashraf Mohamed Hafez, Mohamed Tarek Elawa

Journal of Engineering Research

The role of educational robots is becoming increasingly important. Many commercial educational robots differ in their abilities and price. In general, the cost of these robots presents the main cause of their limited use in the teaching process, especially in countries with limited financial resources. This work attempts to solve this problem by designing and implementing an educational robot with a limited budget. The robot was initially intended to serve higher education students' needs, especially in engineering curriculums but can be extended to other application areas. This work presents robot hardware functional blocks, mechanical struc-ture design, and 3D printing implementation. …

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The Design Studio Dilemma The “Slicing Method”, Yasser Osman El Gammal Associate Professor Dr. Jan 2025

The Design Studio Dilemma The “Slicing Method”, Yasser Osman El Gammal Associate Professor Dr.

Journal of Engineering Research

The design studio presents a multifaceted challenge due to the absence of a direct teaching approach, relying heavily on the teacher's expertise, design acumen, and pace. Furthermore, much of the existing literature on design studio methods tends to be philosophical or opinion-based, lacking practical solutions for ongoing challenges in this domain. While it's easy for scholars to theorize, offering comprehensive procedures to address design studio issues proves considerably more difficult. There's no unanimous agreement on the topic; most design studio models are based on individual opinions as scholars and practitioners view the topic from different angles, developing their own perspectives. …

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A Greening The Diesel: Vegetable Oil Biodiesel Blends For Cleaner Emissions And Improved Direct Injection Diesel Engine Performance, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi, E. A. El Shenawy Prof. Dr., Mustafa Mohamed Ouda Jan 2025

A Greening The Diesel: Vegetable Oil Biodiesel Blends For Cleaner Emissions And Improved Direct Injection Diesel Engine Performance, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi, E. A. El Shenawy Prof. Dr., Mustafa Mohamed Ouda

Journal of Engineering Research

In this study, we conducted comprehensive experiments to assess and compare the performance of pure diesel fuel against biodiesel produced from corn oil in various blend ratios (15/85, 30/70, 45/55, and 60/40) in a conventional four-stroke, direct-injection diesel engine, fuel is injected directly into the combustion chamber at the end of the compression stroke, allowing for efficient combustion and power generation over four distinct phases: intake, compression, power, and exhaust. Each fuel blend was tested at an engine speed of 16,000 rpm across different load conditions (low, medium, and high). Key performance metrics, including volumetric fuel consumption, exhaust smoke, and …

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Recent Literature In Field Ornithology, Continental Birdlife Jan 2025

Recent Literature In Field Ornithology, Continental Birdlife

Continental Birdlife

No abstract provided.

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Recent Literature, Continental Birdlife Jan 2025

Recent Literature, Continental Birdlife

Continental Birdlife

No abstract provided.

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Charting A New Vision: Lessons On Vision & Change From A Network Of Biology Educators, Jeremy L. Hsu, Anjali Misra, Michael J. Wolyniak, Carlos C. Goller, Stephanie Mathews, Uma Swamy, Dina L. Newman, Michael E. Moore Jan 2025

Charting A New Vision: Lessons On Vision & Change From A Network Of Biology Educators, Jeremy L. Hsu, Anjali Misra, Michael J. Wolyniak, Carlos C. Goller, Stephanie Mathews, Uma Swamy, Dina L. Newman, Michael E. Moore

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The 2011 Vision & Change report outlined several recommendations for transforming undergraduate biology education, sparking multiple pedagogical reform efforts. Among these was the Promoting Active Learning and Mentoring (PALM) network, an NSF-funded program that provided mentorship and training to instructors on implementing active learning in the classroom. Here, we provide a perspective on how members of the biology education community in PALM view the recommendations of Vision & Change, drawing upon our experiences both as members of PALM and as leaders of an associated project funded by another NSF grant that hosted PALM alumni at various conferences. These efforts …

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Examining Deep Learning Pixel-Based Classification Algorithms For Mapping Weed Canopy Cover In Wheat Production Using Drone Data, Judith N. Oppong, Clement E. Akumu, Samuel Dennis, Stephanie Anyanwu Jan 2025

Examining Deep Learning Pixel-Based Classification Algorithms For Mapping Weed Canopy Cover In Wheat Production Using Drone Data, Judith N. Oppong, Clement E. Akumu, Samuel Dennis, Stephanie Anyanwu

Agricultural and Environmental Sciences Faculty Research

Deep learning models offer valuable insights by leveraging large datasets, enabling precise and strategic decision-making essential for modern agriculture. Despite their potential, limited research has focused on the performance of pixel-based deep learning algorithms for detecting and mapping weed canopy cover. This study aims to evaluate the effectiveness of three neural network architectures—U-Net, DeepLabV3 (DLV3), and pyramid scene parsing network (PSPNet)—in mapping weed canopy cover in winter wheat. Drone data collected at the jointing and booting growth stages of winter wheat were used for the analysis. A supervised deep learning pixel classification methodology was adopted, and the models were tested …

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Met 235-102: Statics For Technology, Mena Tawfik Jan 2025

Met 235-102: Statics For Technology, Mena Tawfik

School of Applied Engineering and Technology Syllabi

No abstract provided.

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The Nanograv 15 Yr Data Set: Removing Pulsars One By One From The Pulsar Timing Array, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy G. Baier, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. Decesar Jan 2025

The Nanograv 15 Yr Data Set: Removing Pulsars One By One From The Pulsar Timing Array, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy G. Baier, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. Decesar

Pacific Faculty Work

Evidence has emerged for a stochastic signal correlated among 67 pulsars within the 15 yr pulsar-timing data set compiled by the NANOGrav collaboration. Similar signals have been found in data from the European, Indian, Parkes, and Chinese pulsar timing arrays. This signal has been interpreted as indicative of the presence of a nanohertz stochastic gravitational-wave background (GWB). To explore the internal consistency of this result, we investigate how the recovered signal strength changes as we remove the pulsars one by one from the data set. We calculate the signal strength using the (noise-marginalized) optimal statistic, a frequentist metric designed to …

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Strategic Business Communication: A Competency-Based Approach To Writing, Speaking, And Research., Rose Helens-Hart Jan 2025

Strategic Business Communication: A Competency-Based Approach To Writing, Speaking, And Research., Rose Helens-Hart

All Open Educational Resources

This text is for the Honors section of BCOM301 at Fort Hays State University. Business Communication: A Competency-Based Approach to Writing, Speaking, and Research is a practical, engaging book designed to help undergraduate students and business professionals develop competence and build confidence in their business writing, research, and presentation skills. Readers will learn about the five core competencies of business communication: professional, clear, concise, evidence-driven, and persuasive. They also will learn strategies for applying each of these competencies across a range of real-world business documents. This text is a remixing of the following four OER textbooks and original content authored …

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"It's Definitely New And Different...It's Really Engaging": Understanding The Power Of Storytelling Towards Secure Password Creation, Rizu Paudel, Mahdi Nasrullah Al-Ameen Jan 2025

"It's Definitely New And Different...It's Really Engaging": Understanding The Power Of Storytelling Towards Secure Password Creation, Rizu Paudel, Mahdi Nasrullah Al-Ameen

Computer Science Student Research

There is a dearth in existing literature to attain systematic understanding of leveraging digital storytelling in security designs. As we begin to address this gap, we focused on user authentication where the existing password composition policies and password meters often fail to help users around creating a strong and memorable password. To this end, we conducted a lab study with 19 participants, where we updated our initial designs in an iterative manner based on their feedback. We then conducted a between-subject online study with 104 participants over Amazon Mechanical Turk to evaluate our designs. We found that all of our …

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Securing A Virtual Reality Classroom Using Unity, Okemute Samuel Idonor Jan 2025

Securing A Virtual Reality Classroom Using Unity, Okemute Samuel Idonor

Theses and Dissertations

This study examines how security features might be incorporated into a Unity created virtual reality (VR) classroom, with a particular emphasis on important concerns including user privacy, data security, and illegal access. The increasing usage of virtual reality (VR) technology in educational settings has made it crucial to ensure the security of these immersive systems, especially when it comes to safeguarding sensitive user data. Designing and implementing a secure VR classroom prototype that could successfully protect against common security concerns, such as unauthorized access and data breaches, was the main goal of this project. Multi-Factor Authentication (MFA), Role-Based Access Control …

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Detection Of Extended X-Ray Emission Around The Pevatron Microquasar V4641 Sgr With Xrism, Hiromasa Suzuki, Naomi Tsuji, Yoshiaki Kanemaru, Megumi Shidatsu, Laura Olivera-Nieto, Samar Safi-Harb, Shigeo S. Kimura, Eduardo De La Fuente, Sabrina Casanova, Kaya Mori, Xiaojie Wang, Sei Kato, Dai Tateishi, Hideki Uchiyama, Takaaki Tanaka, Hiroyuki Uchida, Shun Inoue, Dezhi Huang Jan 2025

Detection Of Extended X-Ray Emission Around The Pevatron Microquasar V4641 Sgr With Xrism, Hiromasa Suzuki, Naomi Tsuji, Yoshiaki Kanemaru, Megumi Shidatsu, Laura Olivera-Nieto, Samar Safi-Harb, Shigeo S. Kimura, Eduardo De La Fuente, Sabrina Casanova, Kaya Mori, Xiaojie Wang, Sei Kato, Dai Tateishi, Hideki Uchiyama, Takaaki Tanaka, Hiroyuki Uchida, Shun Inoue, Dezhi Huang

Physics Faculty Research & Creative Works

A recent report on the detection of very-high-energy gamma rays from V4641 Sagittarii (V4641 Sgr) up to ≈0.8 PeV has made it the second confirmed "PeVatron" microquasar. Here we report on the observation of V4641 Sgr with X-Ray Imaging and Spectroscopy Mission (XRISM) in 2024 September. Thanks to the large field of view and low background, the CCD imager Xtend successfully detected for the first time X-ray extended emission around V4641 Sgr with a significance of ≳4.5σ and >10σ based on our imaging and spectral analysis, respectively. The spatial extent is estimated to have a radius of 7′ ± 3′ …

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Detection Of Extended X-Ray Emission Around The Pevatron Microquasar V4641 Sgr With Xrism, Hiromasa Suzuki, Naomi Tsuji, Yoshiaki Kanemaru, Megumi Shidatsu, Laura Olivera-Nieto, Samar Safi-Harb, Shigeo S. Kimura, Eduardo De La Fuente, Sabrina Casanova, Kaya Mori, Xiaojie Wang, Sei Kato, Dai Tateishi, Hideki Uchiyama, Takaaki Tanaka, Hiroyuki Uchida, Shun Inoue, Dezhi Huang, Marianne Lemoine-Goumard, Daiki Miura, Shoji Ogawa, Shogo B. Kobayashi, Chris Done, Maxime Parra, Maria Díaz Trigo, Teo Muñoz-Darias, Montserrat Armas Padilla, Ryota Tomaru, Yoshihiro Ueda Jan 2025

Detection Of Extended X-Ray Emission Around The Pevatron Microquasar V4641 Sgr With Xrism, Hiromasa Suzuki, Naomi Tsuji, Yoshiaki Kanemaru, Megumi Shidatsu, Laura Olivera-Nieto, Samar Safi-Harb, Shigeo S. Kimura, Eduardo De La Fuente, Sabrina Casanova, Kaya Mori, Xiaojie Wang, Sei Kato, Dai Tateishi, Hideki Uchiyama, Takaaki Tanaka, Hiroyuki Uchida, Shun Inoue, Dezhi Huang, Marianne Lemoine-Goumard, Daiki Miura, Shoji Ogawa, Shogo B. Kobayashi, Chris Done, Maxime Parra, Maria Díaz Trigo, Teo Muñoz-Darias, Montserrat Armas Padilla, Ryota Tomaru, Yoshihiro Ueda

Michigan Tech Publications

A recent report on the detection of very-high-energy gamma rays from V4641 Sagittarii (V4641 Sgr) up to ≈0.8 PeV has made it the second confirmed “PeVatron” microquasar. Here we report on the observation of V4641 Sgr with X-Ray Imaging and Spectroscopy Mission (XRISM) in 2024 September. Thanks to the large field of view and low background, the CCD imager Xtend successfully detected for the first time X-ray extended emission around V4641 Sgr with a significance of ≳4.5σ and >10σ based on our imaging and spectral analysis, respectively. The spatial extent is estimated to have a radius of 7′ ± 3′ …

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Performance Evaluation Of Free Space Optical Communication In Dar Es Salaam: Impact Of Scintillation And Modulation Schemes, Mustafa H. Mohsini Jan 2025

Performance Evaluation Of Free Space Optical Communication In Dar Es Salaam: Impact Of Scintillation And Modulation Schemes, Mustafa H. Mohsini

Tanzania Journal of Engineering and Technology (TJET)

Free space optical communication (FSO) holds significant relevance in the modern communication system as it offers high and unlimited data rates, enhanced security, rapid deployment, and low cost for installation. However, the performance of FSO transmission is greatly affected by harsh atmospheric conditions such as wind, temperature, and humidity, which induce scintillation. With the rapid growth of internet users and Dar es Salaam being a business city in Tanzania, higher and unlimited bandwidth for communication is highly demanded. This study primarily aims to evaluate the performance of FSO transmission in Dar es Salaam, Tanzania, by investigating the impact of atmospheric …

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Improved Minimum Variance Channel Estimation Techniques For Ofdm Systems, Kwame S. Ibwe Jan 2025

Improved Minimum Variance Channel Estimation Techniques For Ofdm Systems, Kwame S. Ibwe

Tanzania Journal of Engineering and Technology (TJET)

Orthogonal frequency division multiplexing (OFDM) systems face challenges in channel estimation due to noise, variability, and the doubly dispersive nature of wireless channels, which degrade performance. To address these challenges, a multichannel minimum variance double dispersive channel estimator is proposed. The method employs a hybrid approach that combines subspace and minimum variance techniques, optimizing the filter bank output power under a signal-to-noise ratio (SNR) constraint. This design preserves the desired signal while effectively suppressing disturbances, achieving robust performance with reduced computational complexity compared to existing methods. Simulation results demonstrate that the proposed estimator outperforms subspace and asymptotic methods in terms …

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Design And Implementation Of Secured Hybrid Gateway Node For Securing Iot - Enabled Distribution Automation, Ally Bitebo Jan 2025

Design And Implementation Of Secured Hybrid Gateway Node For Securing Iot - Enabled Distribution Automation, Ally Bitebo

Tanzania Journal of Engineering and Technology (TJET)

The integration of smart grid and Internet of Things (IoT) technologies plays a crucial role in enhancing the quality of services provided by traditional electrical grids. This combination has enabled the introduction of new services, such as demand response, automatic meter reading, and IoT-enabled Distribution Automation (IoT-DA), which incorporates sensors, actuators, intelligent electrical devices (IEDs), and information and communication technologies to monitor and control the grid. However, this integration also introduces network security risks, including Denial of Service (DoS) attacks, false data injection, and masquerading attacks, such as system node impersonation that can transmit incorrect readings, trigger false alarms, and …

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Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Revised Final Multi- Pathway Residential Metals Abatement Program (Rmap) Plan (Dated January 13, 2025), Molly Roby Jan 2025

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Revised Final Multi- Pathway Residential Metals Abatement Program (Rmap) Plan (Dated January 13, 2025), Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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