Physical Sciences and Mathematics Commons^™

The Affordable Diy Mandeye Lidar System For Surveying Caves, And How To Convert 3d Clouds Into Traditional Cave Ground Plans And Extended Profiles, Loris Redovniković, Antun Jakopec, Janusz Będkowski, Jurica Jagetić

International Journal of Speleology

The paper examines the potential use of low-cost LiDAR for cave surveying. Mobile mapping using LiDAR complements traditional speleological surveying using a polygonal traverse. These methods assist each other, with one serving as an independent control measurement for the other, ultimately resulting in a more accurate 3D model. The testing results show that achieving high accuracy and detailed cave representation is possible using open hardware and open-source software. Both spacious and well-indented cave sections and narrow passages barely passable by humans were successfully mapped. The surveying process is significantly faster than traditional cave mapping, as drawing cave sketches by hand …

Gravity Tunnel Dynamics At Non-Zero Tunnel Diameters, Shafat Mubin, Walker T. Hayes

Georgia Journal of Science

A standard exercise in undergraduate mechanics derives the trajectory of a particle that has been dropped through a gravity tunnel passing through the center of the Earth as simple harmonic oscillation, assuming uniform earth density and negligible tunnel radius. We show that when the more accurate Preliminary Reference Earth Model (PREM) density profile and non-negligible tunnel radii are taken into consideration, significant deviations from harmonic oscillation are observed along with increasing or decreasing average particle speeds. Furthermore, we report that a particle traveling along a diameter perpendicular to the axis of the gravity tunnel is unable to reach the center …

Confocal Laser Scanning Microscopy As A Method For Identifying Variation In Puparial Morphology And Establishing Characters For Taxonomic Determination, Christian Elowsky, Leon G. Higley

School of Natural Resources: Faculty Publications

Calliphoridae, or blow flies, are of much ecological and practical importance given their roles in decompositional ecology, medical and veterinary myiasis, and forensic entomology. As ephemeral and rapidly developing species, adults are frequently not present for identification, but puparia (the remaining outer integument of the third instar larvae) are frequently found. These heavily sclerotized remains are stable in the environment but they are of a conservative character. Historically, scanning electron microscopy (SEM) has been used for characterization, a technique which is not only time-consuming but also often expensive, effectively making large numbers of specimens impossible to quantify. As an alternative, …

Toward Alleviating The 𝐻₀ And 𝑆₈ Tensions With Early Dark Energy-Dark Matter Drag, T. Simon, T. Adi, J. L. Bernal, E. D. Kovetz, V. Poulin, Tristan L. Smith

Physics & Astronomy Faculty Works

Early dark energy, an additional component of dark energy active in the decade of redshift before recombination, has emerged as one of the most effective models at reducing the “𝐻₀ tension” between direct measurement of the Hubble parameter 𝐻₀ in the late Universe and the Λ CDM prediction when calibrated on Planck. However, it requires a slight increase in the dark matter density 𝜔_cdm and primordial tilt 𝑛_𝑠 that worsens the “𝑆₈ tension” between measurements of weak gravitational lensing at low redshifts and the Planck/Λ⁢CDM prediction. Using a phenomenological fluid model, we investigate whether the inclusion …

01.13.2025 Ored Connect, Liz Williamson

ORED Newsletter

NIH Public Access Policy Update

Procurement Information for Award Spending online course announcement

National Sea Grant Law Center funding

Temporal Scales Of Sediment Accumulation, Mass Wasting, And Stratigraphy Across The Mississippi River Delta Front, Jeffrey E. Duxbury

LSU Doctoral Dissertations

The Mississippi River Delta Front (MRDF) is a subaqueous apron of rapidly deposited, weakly

consolidated sediment extending from the subaerial portions of the Mississippi River’s Birdsfoot Delta, historically known for sediment transport via mass wasting. To better understand the spatial and temporal dynamics of processes influencing the MRDF, 29 cores ranging from 5.8 to 8.71 meters in length were collected from the South Pass (SP) and Southwest Passes (SWP). These cores targeted specific depositional environments, including the undisturbed topset apron, medial mudflow gully, mudflow lobe, and prodelta. The cores were analyzed along their full lengths for gamma density, grain size, …

Spatial And Spectral Characterization Of The Gravitational-Wave Background With The Pta Optimal Statistic, Kyle A. Gersbach, Stephen R. Taylor, Patrick M. Meyers, Joseph D. Romano

Physics & Astronomy Faculty Publications

Pulsar timing arrays (PTAs) have made tremendous progress and are now showing strong evidence for the gravitational-wave background (GWB). Further probing the origin and characteristics of the GWB will require more generalized analysis techniques. Bayesian methods are most often used but can be computationally expensive. On the other hand, frequentist methods, like the PTA optimal statistic (OS), are more computationally efficient and can produce results that are complementary to Bayesian methods, allowing for stronger statistical cases to be built from a confluence of different approaches. In this work we expand the capabilities of the OS through a technique we call …

Hydrogen Diffusion Into Water And Cushion Gases – Relevance For Hydrogen Geo-Storage, Quoc Truc Doan, Alireza Keshavarz, Peter Behrenbruch, Stefan Iglauer

Research outputs 2022 to 2026

Hydrogen (H2) has been recognized as a promising solution to reduce carbon dioxide (CO2) emissions. H2 is considered a green energy carrier for energy storage, transport, and usage, and it can be produced from renewable energy resources (such as solar, hydropower, and wind energy). However, H2 is a highly diffusive compound compared to other natural gases, raising concerns about the possibility of H2 loss in geo-storage (e.g. in underground geological formations such as depleted oil/gas reservoirs, aquifers or shale formations) or H2 leak via pipelines when blending H2 with natural gas in existing pipeline systems. Thus, understanding H2 diffusion in …

Counting Rotational Subsets Of The Circle $\Mathbb{R}/ \Mathbb{Z}$ Under The Angle-Multiplying Map $T\Mapsto Dt$, Ian Tan

Rose-Hulman Undergraduate Mathematics Journal

A rotational set is a finite subset $A$ of the unit circle $\mathbb{R}/ \mathbb{Z}$ such that the angle-multiplying map $\sigma_{d}:t\mapsto dt$ maps $A$ onto itself by a cyclic permutation of its elements. Each rotational set has a geometric rotation number $p/q$. Lisa Goldberg introduced these sets to study the dynamics of complex polynomial maps. In this paper, we provide a necessary and sufficient condition for a set to be $\sigma_{d}$-rotational with rotation number $p/q$. As applications of our condition, we recover two classical results and enumerate $\sigma_d$-rotational sets with rotation number $p/q$ that consist of a given number of orbits.

Feasibility Study For Providing Remedial Measures For Overburden Dump In New Majri Ug To Oc Mine, Wcl Majri Area, Warora, Chandrapur, Himanshu Kumar Jangir, Rahul Shende, Omkar Navagire, Srinivasan Venkatraman, Anirban Mandal, Anjan Patel

Journal of Sustainable Mining

The central region of India is abundant in fertile black cotton soil, and the presence of such weak floors in open-cast mines poses significant slope stability concerns for overburden (OB) dumps. Addressing these issues is crucial for ensuring safe mining operations and cost-effectiveness. Several coal mines in this region have experienced overburden dump collapses due to the weak soil foundation. To enhance slope stability and mitigate the heaving effect near the toe of the dump, this study proposes parametric research that explores the flattening of the overall slope angle of the dump, bench angle optimization, and various feasible dimensions for …

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 …

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 …

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 …

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 …

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 …

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 …

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 + …

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. …

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 …

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 …

"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 …

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 …

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.

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 …

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 …

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 …

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′ …

Mathematics In Everyday Life: Exploring Practical Applications And Real-World Impact, Priyant Banerjee, Arshad Bhat

Himalayan Research Papers Archive

Mathematics is an essential part of daily life and influences decisions and problem-solving in various aspects of life. This study explores how mathematical concepts are embedded in daily activities such as financial management, cooking, travel planning, and technological interactions. We will show how arithmetic, algebra, geometry, and statistics are applied in real life to improve decision-making, efficiency, and productivity. Findings indicate that people with higher mathematical literacy solve problems more efficiently, especially in budgeting, as accurate calculations minimize financial mistakes and facilitate long-term financial planning. In cooking, proportional reasoning ensures the accuracy of recipes, thus providing consistent culinary results. Travel …

Effects Of Technical Debt On Software Interoperability, Leonard Peter Binamungu

Tanzania Journal of Engineering and Technology (TJET)

Technical debt (TD) refers to sub-optimal development decisions that make the software costly to maintain and evolve. Examples of TD include structural complexity, violation of coding styles, and code complexity. Existing research has investigated the nature, causes and indicators of TD, as well as tools and strategies for managing TD. However, although TD could hinder the ability of a software system to be interoperable with others, existing literature has limited evidence on how TD affects systems interoperability. This limits the ability of software engineering teams to manage TD in ways that do not hinder systems interoperability. To fill this void, …

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′ …