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2021

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Articles 61 - 90 of 1349

Full-Text Articles in Physics

Proposed Hybrid Correlationfeatureselectionforestpanalizedattribute Approach To Advance Idss, Doaa Nteesha Mhawi, Prof. Soukaena H. Hashem Dec 2021

Proposed Hybrid Correlationfeatureselectionforestpanalizedattribute Approach To Advance Idss, Doaa Nteesha Mhawi, Prof. Soukaena H. Hashem

Karbala International Journal of Modern Science

NetworkIntrusionDetectionSystem(NIDS), widely used network infrastructure. Although many datamining has been used to increase the effectiveness of IDSs, current ID still struggle to perform well. therfore; proposed a new NIDS focused on feature_selection. The proposed CorrelationFeatureSelection_ForestPanalizedAttributes(CFS_FPA) used for dimensionality_reduction and selects the optimal_subset. based on two steps: first check each feature with a target(class) and choose only features that most effective by applying CFS filter using a statistical_method, then applied FPA to select only features will enhance ID and reduce_dimensionality. proposal tested with the NSLKDD experimental results of accuracy 0.997% and 0.004 FAR, wherein UNSWNB15_dataset accuracy and FAR are 0.995%, 0.008 …

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Analysis Of Modern Communication Protocols For Iot Applications, Neerendra Kumar, Pragti Jamwal Dec 2021

Analysis Of Modern Communication Protocols For Iot Applications, Neerendra Kumar, Pragti Jamwal

Karbala International Journal of Modern Science

To facilitate increasing interactions of machines, various protocols are building up for IoT applications. Safeguarding communication among devices is necessary. In this paper, various protocols have been studied and compared using six parameters: Communication overhead, Security, Packet Loss, Throughput, Bandwidth and Support to QoS. LIDOR is found as the most successful communication protocol. A tabulated comparison of various communication protocols have been provided by comparing the parameters. Further, six star rating for the various protocols have been proposed. The study shows that LIDOR increases reliability under DoS attacks. Considering the existing literature, new research gaps and challenges have been presented.

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The Effect Of Diode Laser On The Life And Appearance Of White Ant (Psammotermes Hypostoma), Estabraq Mahmood Mahdi Msc, Sahar Naji Rashid Msc., Saeed Maher Lafta Ph.D., Arshad Mahdi Hamad Msc Dec 2021

The Effect Of Diode Laser On The Life And Appearance Of White Ant (Psammotermes Hypostoma), Estabraq Mahmood Mahdi Msc, Sahar Naji Rashid Msc., Saeed Maher Lafta Ph.D., Arshad Mahdi Hamad Msc

Karbala International Journal of Modern Science

This work focused on studying effect of diode laser on external appearance of white ants, and finding the percentage of mortality resulting from this beam of (650nm),(5mW),exposure times (60,70,80,90,100)sec at (3,5)cm for each exposure. The results recorded showed a clear increase in death rates, and increase in deformations as laser exposure times increased (higher percentage at lower distance), where laser was used to capture results of this therapeutic effect after passage time periods (12,24,48,72)hours. These results, show laser thermal effects resulting from its interaction with tissues, thermal propagation leads to ravage to the structures, thus to an increase death rates.

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Calculation And Comparison Of Certain Physical Properties Of Sample Irregular Galaxies With The Milky Way Galaxy, Hasanain Hassan Al-Dahlaki Msc Dec 2021

Calculation And Comparison Of Certain Physical Properties Of Sample Irregular Galaxies With The Milky Way Galaxy, Hasanain Hassan Al-Dahlaki Msc

Karbala International Journal of Modern Science

Irregular galaxies often include a mix of old and young celestial populations, as well as dust and gas. This study makes an early effort at the morphological classification of irregular galaxies. These sources have been chosen from (70) irregular galaxies data samples from a Catalogue survey. We present a statistical analysis of the physical properties for the chosen data from the database and a collection of tools that used to study the physics of galaxies and cosmology HYPERLEDA (http://atlas.obshp.fr/hyperleda/) and NASA /IPAC Extragalactic Database NED (https://ned.ipac.caltech.edu/) survey.

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Seasonal Variation Of Microbiota In Shank Acanthopagrus Latus Living In Both Brackish And Fresh Water, Ali A. Al-Hisnawi Ph.D., Jassim M. Mustafa, Yass K. Yasser, Khalid A. Hussain, Ameera M. Jabur Dec 2021

Seasonal Variation Of Microbiota In Shank Acanthopagrus Latus Living In Both Brackish And Fresh Water, Ali A. Al-Hisnawi Ph.D., Jassim M. Mustafa, Yass K. Yasser, Khalid A. Hussain, Ameera M. Jabur

Karbala International Journal of Modern Science

The present study was conducted to monitor the microbiota in the posterior intestine of Shank fish living in the river (fresh water) and Al-Razzaza lake (salt or brackish water) in Kerbala, Iraq. Cultivable bacteria were calculated and identified from specimens obtained from the posterior intestine of mucosa (PM) and digesta (PD) during summer and winter seasons. The total culturable bacteria (TCB) of bacteria isolated from both intestinal regions from fresh water fish during summer time were higher than counterparts in winter time. In contrast, the TVC of bacteria isolated from the PM from salt water fish during winter time were …

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Evaluation Of The Healing Activity Of Cucurbita Spp. Leaf And Seed Extracts On Experimental Thermal Burns, Sanaa Jameel Thamer Ph.D., Prof. Maha Khalil Ibrahim, Dr. Khalid Shanshal Alnema Dec 2021

Evaluation Of The Healing Activity Of Cucurbita Spp. Leaf And Seed Extracts On Experimental Thermal Burns, Sanaa Jameel Thamer Ph.D., Prof. Maha Khalil Ibrahim, Dr. Khalid Shanshal Alnema

Karbala International Journal of Modern Science

Burns are the most common skin injuries associated with many complications and high incidences of wound infections. Many compounds of plant products have been assessed to accelerate wound healing or reduce contamination. The possible healing effect of two Cucurbita spp. in skin burns was investigated. Cucurbita maxima and Cucurbita pepo leaves and seeds were extracted using ethanol and analyzed by gas chromatography–mass spectrometry. Second-degree burn wounds were made on laboratory rats, and the burn wounds were applied topically with extracts for 14 days and silver sulfadiazine (SS) for comparison. Serum vascular endothelial growth factor (VEGF) was analyzed post-treatment. Hydroxyproline content …

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Energy Conservation Approach Of Wireless Sensor Networks For Iot Applications, Suha Abdulhussein Abdulzahra Msc, Ali Kadhum M. Al-Qurabat Ph.D., Prof. Dr. Ali Kadhum Idrees Dec 2021

Energy Conservation Approach Of Wireless Sensor Networks For Iot Applications, Suha Abdulhussein Abdulzahra Msc, Ali Kadhum M. Al-Qurabat Ph.D., Prof. Dr. Ali Kadhum Idrees

Karbala International Journal of Modern Science

Wireless Sensor Network is one of the most important contributors to IoT and performs significant role in people's lives due to its extensive use in many applications. Energy-saving is essential since sensor nodes are working by their restricted battery. In this article, data reduction method proposed to work at Gateway level of network. In GW, proposed method works as filtering via enabling GW to identify, then remove, sets of data that are redundant and produced by neighboring nodes. Principle idea of method recommended at this level is to exploit the advantage of spatial correlation between sensors to minimize energy depletion.

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Biosynthesis, Characterization And Antiproliferative Activity Of Green Synthesized Gold Nanoparticles Using Lantadene A Extracted From Lantana Camara, Dawood Ali Salim Dawood, Lee Suan Chua Ph.D, Tian Swee Tan Ph.D, Ahmed F. Alshemary Ph.D Dec 2021

Biosynthesis, Characterization And Antiproliferative Activity Of Green Synthesized Gold Nanoparticles Using Lantadene A Extracted From Lantana Camara, Dawood Ali Salim Dawood, Lee Suan Chua Ph.D, Tian Swee Tan Ph.D, Ahmed F. Alshemary Ph.D

Karbala International Journal of Modern Science

This study was focused on the biosynthesis of gold nanoparticles loaded with lantadene A (LA-AuNPs) from Lantana camara extract and the antiproliferative effects on prostate cancer cells (LNCaP). The synthesized LA-AuNPs had smooth surface, and nearly spherical in shape (67.94 nm) with the zeta potential (-30.11±0.83 mV). LAAuNPs showed a dose dependent cytotoxic activity with IC50, 126.82 µg/mL against LNCaP, but non-cytotoxic to normal prostate cells. The intrinsic pathway of apoptosis was caused by the increase of caspases-3/7 and -9 activity and cell cycle arrest at the G0/G1 phase. Therefore, LA-AuNPs could be a potent lead to inhibit LNCaP

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An Online E-Voting System Based On An Adaptive Ledger With Singular Value Decomposition Technique, Rihab Habeeb Sahib, Prof. Dr. Eman Salih Al-Shamery Dec 2021

An Online E-Voting System Based On An Adaptive Ledger With Singular Value Decomposition Technique, Rihab Habeeb Sahib, Prof. Dr. Eman Salih Al-Shamery

Karbala International Journal of Modern Science

Regular E-voting systems for elections may count the votes in less time,less cost,save the privacy of citizens,but still considered risky as votes can be tampered.E-voting systems based on a network distributed ledger show fast results,more trusted,save privacy,cannot be tampered,and distributed in which no central organization controls the system.This paper illustrate an e-voting system to solve the challenge of a massive ledger that is distributed among network-nodes using a data reduction technique as a security-matching-tool,singular value decomposition(SVD) that handle a copy of election results in another form and matched with the SQL-database results to announce a successful election-event representing a transparency-powerful-secured-system

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Detecting Malicious Dns Queries Over Encrypted Tunnels Using Statistical Analysis And Bi-Directional Recurrent Neural Networks, Mohammad Al-Fawa'reh, Zain Ashi, Mousa Tayseer Jafar Dec 2021

Detecting Malicious Dns Queries Over Encrypted Tunnels Using Statistical Analysis And Bi-Directional Recurrent Neural Networks, Mohammad Al-Fawa'reh, Zain Ashi, Mousa Tayseer Jafar

Karbala International Journal of Modern Science

The exponential rise in the number of malicious threats targeting computer networks and digital services puts network infrastructure in jeopardy. Domain name protocol attacks are one of the most pervasive network attacks posing a threat to networks, whereby attackers send harmful information to the network; this type of threat is identified as DNS tunneling. The DNS protocol has recently gained increased attention from cyber-attackers, targeting organizations with a web presence or reliance on e-commerce businesses. Cyber-attackers can subtly exploit the contents of encrypted DNS packets that are sent across covert network tunnels, which are difficult for firewalls and blacklist detection …

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Artificial Intelligence For Para Rubber Identification Combining Five Machine Learning Methods, Chairote Yaiprasert Ph.D. Dec 2021

Artificial Intelligence For Para Rubber Identification Combining Five Machine Learning Methods, Chairote Yaiprasert Ph.D.

Karbala International Journal of Modern Science

This study aims to identify Para rubber species using a combination of five machine learning techniques to classify leaf images. The learning process is defined using a dataset for each classification method. Approximately 1,472 leaf images are prepared consisting of various sizes, shapes, quality provided for the model. The classification indicators are defined with the help of an algorithm to identify at least three of the top five potential classification outcomes. The algorithm accurately predicts 100% of the five classification methods. Methods can provide precise and rapid classification of large quantities, without the need for image preprocessing prior to classification.

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Synergistic Extraction Of Silver From Nitric Acid Medium With Dithizone In The Presence Of A Secondary Amine- Amberlite La-2 Using 110mag-Radioisotope, Madhusudan Mandal Ph.D. Dec 2021

Synergistic Extraction Of Silver From Nitric Acid Medium With Dithizone In The Presence Of A Secondary Amine- Amberlite La-2 Using 110mag-Radioisotope, Madhusudan Mandal Ph.D.

Karbala International Journal of Modern Science

Synergistic extraction of silver has been investigated in the presence of two different kinds of extractants, one of which is a chelating ligand, dithizone and the other is a long-chain secondary amine amberlite LA-2 at pH 3.0 using a radiotracer technique. The apparent formation constant, overall equilibrium constant and adduct formation constants were calculated from distribution coefficients. Interestingly, it was observed that the adduct formation constant is too high when the ligand concentration is increased by keeping the amine concentration fixed at 0.044 M compared to that obtained when the ligand concentration is kept fixed at 8.74×10-4 M.

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Editorial Board Dec 2021

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.

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Effects Of Anharmonicity In A Dual-Sagnac Interferometer, Stephen Thomas Dec 2021

Effects Of Anharmonicity In A Dual-Sagnac Interferometer, Stephen Thomas

Honors College Theses

A recent experiment implemented a dual Sagnac atom interferometer (AI) for rotation sensing using a Bose-Einstein condensate (BEC) confined in a TOP-trap potential. The BEC is split twice by laser light to create two pairs of counter-orbiting clouds in a lowest-order harmonic potential with each pair acting as a separate Sagnac interferometer. After one orbit the two overlapping cloud pairs are split again and the interference patterns are inferred from the population of atoms in the zero-momentum state. We have simulated the impact of the presence of anharmonic terms in the potential on the performance of the AI as measured …

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Extracellular Vimentin As A Target Against Sars-Cov-2 Host Cell Invasion, Łukasz Suprewicz, Maxx Swoger, Sarthak Gupta, Ewelina Piktel, Fitzroy J. Byfield, Daniel V. Iwamoto, Danielle Germann, Joanna Reszeć, Natalia Marcińczyk, Robert J. Carroll, Paul A. Janmey, J. M. Schwarz, Robert Bucki, Alison E. Patteson Dec 2021

Extracellular Vimentin As A Target Against Sars-Cov-2 Host Cell Invasion, Łukasz Suprewicz, Maxx Swoger, Sarthak Gupta, Ewelina Piktel, Fitzroy J. Byfield, Daniel V. Iwamoto, Danielle Germann, Joanna Reszeć, Natalia Marcińczyk, Robert J. Carroll, Paul A. Janmey, J. M. Schwarz, Robert Bucki, Alison E. Patteson

Physics - All Scholarship

Infection of human cells by pathogens, including SARS-CoV-2, typically proceeds by cell surface binding to a crucial receptor. The primary receptor for SARS-CoV-2 is the angiotensin-converting enzyme 2 (ACE2), yet new studies reveal the importance of additional extracellular co-receptors that mediate binding and host cell invasion by SARS-CoV-2. Vimentin is an intermediate filament protein that is increasingly recognized as being present on the extracellular surface of a subset of cell types, where it can bind to and facilitate pathogens’ cellular uptake. Biophysical and cell infection studies are done to determine whether vimentin might bind SARS-CoV-2 and facilitate its uptake. Dynamic …

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Accurate Flux Calibration Of Gw170817: Is The X-Ray Counterpart On The Rise?, E. Troja, B. O'Connor, G. Ryan, L. Piro, R. Ricci, B. Zhang, T. Piran, G. Bruni, S. B. Cenko, H. Van Eerten Dec 2021

Accurate Flux Calibration Of Gw170817: Is The X-Ray Counterpart On The Rise?, E. Troja, B. O'Connor, G. Ryan, L. Piro, R. Ricci, B. Zhang, T. Piran, G. Bruni, S. B. Cenko, H. Van Eerten

Physics & Astronomy Faculty Research

X-ray emission from the gravitational wave transient GW170817 is well described as non-thermal afterglow radiation produced by a structured relativistic jet viewed off-axis. We show that the X-ray counterpart continues to be detected at 3.3 years after the merger. Such long-lasting signal is not a prediction of the earlier jet models characterized by a narrow jet core and a viewing angle ≈20 deg, and is spurring a renewed interest in the origin of the X-ray emission. We present a comprehensive analysis of the X-ray dataset aimed at clarifying existing discrepancies in the literature, and in particular the presence of an …

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Evidence For Quasi-Periodic Oscillations In The Recurrent Emission From Magnetars And Their Implications On The Neutron Star Properties And Equation Of State, Ahmed Monzer El Mezeini Dec 2021

Evidence For Quasi-Periodic Oscillations In The Recurrent Emission From Magnetars And Their Implications On The Neutron Star Properties And Equation Of State, Ahmed Monzer El Mezeini

Archived Theses and Dissertations

In this thesis, we present an analysis of highly magnetized neutron stars â magnetarsâ , in search for high frequency oscillations in the recurrent emission from the soft gamma repeater SGR 1806-20, and we discuss the physical interpretation of these oscillations and its implications on the neutron star properties and structure. We present evidence for Quasi-Periodic Oscillations (QPOs) in the recurrent outburst activity from the soft gamma repeater SGR 1806-20 using Rossi X-ray Timing Explorer (RXTE) observations. By searching a large sample of bursts for timing signals at the frequencies of the QPOs discovered in the 2004 December 27 giant …

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Evidence For Surface Effects On The Intermolecular Interactions In Fe (Ii) Spin Crossover Coordination Polymers, Thilini K. Ekanayaka, Hannah Kurz, Kayleigh A. Mcelveen, Guanhua Hao, Esha Mishra, Alpha T. N’Diaye, Rebecca Lai, Birgit Weber, Peter A. Dowben Dec 2021

Evidence For Surface Effects On The Intermolecular Interactions In Fe (Ii) Spin Crossover Coordination Polymers, Thilini K. Ekanayaka, Hannah Kurz, Kayleigh A. Mcelveen, Guanhua Hao, Esha Mishra, Alpha T. N’Diaye, Rebecca Lai, Birgit Weber, Peter A. Dowben

Department of Physics and Astronomy: Faculty Publications

From X-ray absorption spectroscopy (XAS) and X-ray photoemission spectroscopy (XPS) it is evident that the spin state transition behavior of Fe(II) spin crossover coordination polymer crystallites at the surface differs from the bulk. A comparison of four different coordination polymers reveals that the observed surface properties may differ from bulk for a variety of reasons. There are Fe(II) spin crossover coordination polymers with either almost complete switching of the spin state at the surface or no switching at all. Oxidation, differences in surface packing, and changes in coordination could all contribute to making the surface very different from the bulk. …

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Measurement Of Speed Of Sound Using Smartphones, Omotolani Adelekan Dec 2021

Measurement Of Speed Of Sound Using Smartphones, Omotolani Adelekan

Publications and Research

The goal of this experiment is to determine the speed of sound in air. To measure the speed of sound, I used two smartphones and an app called Phyphox This app uses the microphone of the smartphone to detect the time between two acoustic events The “acoustic stopwatch” tool on the app is used to measure the time between two sound signals These two signals are produced by hand clapping In this experiment, the speed of sound is determined using the time of flight method This method is based on measuring the time delay between the generation and the detection …

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(R1480) Heat Transfer In Peristaltic Motion Of Rabinowitsch Fluid In A Channel With Permeable Wall, Mahadev M. Channakote, Dilipkumar V. Kalse Dec 2021

(R1480) Heat Transfer In Peristaltic Motion Of Rabinowitsch Fluid In A Channel With Permeable Wall, Mahadev M. Channakote, Dilipkumar V. Kalse

Applications and Applied Mathematics: An International Journal (AAM)

This paper is intended to investigate the effect of heat transfer on the peristaltic flow of Rabinowitsch fluid in a channel lined with a porous material. The Navier -Stokes equation governs the channel's flow, and Darcy's law describes the permeable boundary. The Rabinowitsch fluid model's governing equations are solved by utilizing approximations of the long-wavelength and small number of Reynolds. The expressions for axial velocity, temperature distribution, pressure gradient, friction force, stream function are obtained. The influence on velocity, pressure gradient, friction force, and temperature on pumping action of different physical parameters is explored via graphs.

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Quantum State Estimation And Tracking For Superconducting Processors Using Machine Learning, Shiva Lotfallahzadeh Barzili Dec 2021

Quantum State Estimation And Tracking For Superconducting Processors Using Machine Learning, Shiva Lotfallahzadeh Barzili

Computational and Data Sciences (PhD) Dissertations

Quantum technology has been rapidly growing; in particular, the experiments that have been performed with superconducting qubits and circuit QED have allowed us to explore the light-matter interaction at its most fundamental level. The study of coherent dynamics between two-level systems and resonator modes can provide insight into fundamental aspects of quantum physics, such as how the state of a system evolves while being continuously observed. To study such an evolving quantum system, experimenters need to verify the accuracy of state preparation and control since quantum systems are very fragile and sensitive to environmental disturbance. In this thesis, I look …

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Voltage Controlled Néel Vector Rotation In Zero Magnetic Field, Ather Mahmood, Will Echtenkamp, Mike Street, Jun Lei Wang, Shi Cao, Takashi Komesu, Peter Dowben, Pratyush Buragohain, Haidong Lu, Alexei Gruverman, Arun Parthasarathy, Shaloo Rakheja, Christian Binek Dec 2021

Voltage Controlled Néel Vector Rotation In Zero Magnetic Field, Ather Mahmood, Will Echtenkamp, Mike Street, Jun Lei Wang, Shi Cao, Takashi Komesu, Peter Dowben, Pratyush Buragohain, Haidong Lu, Alexei Gruverman, Arun Parthasarathy, Shaloo Rakheja, Christian Binek

Peter Dowben Publications

Multi-functional thin films of boron (B) doped Cr2O3 exhibit voltage-controlled and nonvolatile Néel vector reorientation in the absence of an applied magnetic field, H. Toggling of antiferromagnetic states is demonstrated in prototype device structures at CMOS compatible temperatures between 300 and 400 K. The boundary magnetization associated with the Néel vector orientation serves as state variable which is read via magnetoresistive detection in a Pt Hall bar adjacent to the B:Cr2O3 film. Switching of the Hall voltage between zero and non-zero values implies Néel vector rotation by 90 degrees. Combined magnetometry, spin resolved inverse …

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Quantum State Tomography Of Molecules By Ultrafast Diffraction, Ming Zhang, Shuqiao Zhang, Yanwei Xiong, Hankai Zhang, Anatoly A. Ischenko, Oriol Vendrell, Xiaolong Dong, Xiangxu Mu, Martin Centurion, Haitan Xu, R. J.Dwayne Miller, Zheng Li Dec 2021

Quantum State Tomography Of Molecules By Ultrafast Diffraction, Ming Zhang, Shuqiao Zhang, Yanwei Xiong, Hankai Zhang, Anatoly A. Ischenko, Oriol Vendrell, Xiaolong Dong, Xiangxu Mu, Martin Centurion, Haitan Xu, R. J.Dwayne Miller, Zheng Li

Martin Centurion Publications

Ultrafast electron diffraction and time-resolved serial crystallography are the basis of the ongoing revolution in capturing at the atomic level of detail the structural dynamics of molecules. However, most experiments capture only the probability density of the nuclear wavepackets to determine the time-dependent molecular structures, while the full quantum state has not been accessed. Here, we introduce a framework for the preparation and ultrafast coherent diffraction from rotational wave packets of molecules, and we establish a new variant of quantum state tomography for ultrafast electron diffraction to characterize the molecular quantum states. The ability to reconstruct the density matrix, which …

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The Hashtag Project: The First Submillimeter Images Of The Andromeda Galaxy From The Ground, Matthew W.L. Smith, Stephen A. Eales, Thomas G. Williams, Bumhyun Lee, Zongnan Li, Pauline Barmby, Martin Bureau, Scott Chapman, Brian S. Cho, Aeree Chung, Eun Jung Chung, Hui Hsuan Chung, Christopher J.R. Clark, David L. Clements, Timothy A. Davis, Ilse De Looze, David J. Eden, Gayathri Athikkat-Eknath, George P. Ford, Yu Gao, Walter Gear, Haley L. Gomez, Richard De Grijs, Jinhua He, Luis C. Ho, Thomas M. Hughes, Sihan Jiao, Zhiyuan Li, Francisca Kemper Dec 2021

The Hashtag Project: The First Submillimeter Images Of The Andromeda Galaxy From The Ground, Matthew W.L. Smith, Stephen A. Eales, Thomas G. Williams, Bumhyun Lee, Zongnan Li, Pauline Barmby, Martin Bureau, Scott Chapman, Brian S. Cho, Aeree Chung, Eun Jung Chung, Hui Hsuan Chung, Christopher J.R. Clark, David L. Clements, Timothy A. Davis, Ilse De Looze, David J. Eden, Gayathri Athikkat-Eknath, George P. Ford, Yu Gao, Walter Gear, Haley L. Gomez, Richard De Grijs, Jinhua He, Luis C. Ho, Thomas M. Hughes, Sihan Jiao, Zhiyuan Li, Francisca Kemper

Physics and Astronomy Publications

Observing nearby galaxies with submillimeter telescopes on the ground has two major challenges. First, the brightness is significantly reduced at long submillimeter wavelengths compared to the brightness at the peak of the dust emission. Second, it is necessary to use a high-pass spatial filter to remove atmospheric noise on large angular scales, which has the unwelcome side effect of also removing the galaxy's large-scale structure. We have developed a technique for producing high-resolution submillimeter images of galaxies of large angular size by using the telescope on the ground to determine the small-scale structure (the large Fourier components) and a space …

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Hobby Grade Lithium-Ion Batteries For Spacecraft Applications: Establishing An Automated Electrical Characteristics Testing Procedure For Flight Acceptance Of Non-Space-Grade Small Secondary Batteries, Braidon Hughes Dec 2021

Hobby Grade Lithium-Ion Batteries For Spacecraft Applications: Establishing An Automated Electrical Characteristics Testing Procedure For Flight Acceptance Of Non-Space-Grade Small Secondary Batteries, Braidon Hughes

Graduate Theses and Dissertations

Li-ion batteries are widely used due to the large amount of rechargeable energy they pack into a small, light package. This higher energy density makes Li-ion batteries ideal for small satellite applications, specifically CubeSats. CubeSats have grown in popularity in higher level education due to the National Aeronautics and Space Administration’s implementation of the Cube Satellite Launch Initiative, making it easier and cheaper to conduct small, low orbit missions. Because these CubeSats are occupying the same space as a crewed spacecraft, it is imperative that they are safe. There are numerous reports of Li-ion batteries creating fires that result in …

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Clmm: A Lsst-Desc Cluster Weak Lensing Mass Modeling Library For Cosmology, H. Wu Dec 2021

Clmm: A Lsst-Desc Cluster Weak Lensing Mass Modeling Library For Cosmology, H. Wu

Physics Faculty Publications and Presentations

We present the v1.0 release of CLMM, an open source PYTHON library for the estimation of the weak lensing masses of clusters of galaxies. CLMM is designed as a stand-alone toolkit of building blocks to enable end-to-end analysis pipeline validation for upcoming cluster cosmology analyses such as the ones that will be performed by the Vera C. Rubin Legacy Survey of Space and Time-Dark Energy Science Collaboration (LSST-DESC). Its purpose is to serve as a flexible, easy-to-install, and easy-to-use interface for both weak lensing simulators and observers and can be applied to real and mock data to study the systematics …

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Lorentz Violations And The Casimir Effect, Samuel G. Christensen Dec 2021

Lorentz Violations And The Casimir Effect, Samuel G. Christensen

Physics

The background and calculation for the corrections to the Casimir Energy stored on parallel conducting plates due to minimal violations of Lorentz invariance are presented as a test of the Standard Model. A direction-dependent photon dispersion relation using operators of dimension 4 and higher is used in the calculation of the spacetime anisotropy correction terms to the Casimir energy. The calculation includes discussion of Riemann zeta function regularization and its equivalence to Euler-Maclaurin sum-integral formulas in a Casimir effect calculation. The two plate geometry result is mapped onto a one plate and sphere geometry to cater to modern precision tests …

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Rigid Aggregation Of Inclusions Embedded In Quasi 2d Fluids, Natalie Xochitl Ryan Dec 2021

Rigid Aggregation Of Inclusions Embedded In Quasi 2d Fluids, Natalie Xochitl Ryan

Physics

Diffusion is a transport process common in several biological systems. In this process particles of different species mix together through random (stochastic) motion at molecular length scales. Diffusion in fluids is unique as the coupling of the flow and fluid have been found to produce giant concentration fluctuations. The molecular length scale of these concentration fluctuations are magnitudes larger than the movement of the particles themselves, earning them the title “giant”. The diffusion of particles in bio-membranes displays a combination of 2D and 3D hydrodynamic properties; the movements of the particles are restricted to the plane of the membrane and …

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Equivalence: A Covariantly Constant Problem In General Relativity, Jaren Hobbs Dec 2021

Equivalence: A Covariantly Constant Problem In General Relativity, Jaren Hobbs

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

In studying the space-time structures described by Einstein’s theory of general relativity, it is often useful to identify particular properties referred to as geometrical invariants. These are attributes of the space-times which do not change regardless of the underlying coordinate systems used to study them. This project is part of a larger effort to catalogue space-times studied in general relativity. Specifically, computational software was used to identify structures known as covariantly constant vector fields.

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Electroluminescent Signals And Cosmogenicbackgrounds In High Pressure Xenon Gas Timeprojection Detectors, Leslie Rogers Dec 2021

Electroluminescent Signals And Cosmogenicbackgrounds In High Pressure Xenon Gas Timeprojection Detectors, Leslie Rogers

Physics Dissertations - Archive

The NEXT collaboration is developing a sequence of high pressure xenon gas time projection chambers with the aim of creating a ton-scale, very low background neutrinoless double beta decay search. Finding evidence of neutrinoless double beta decay would give insight into the origins of the matter-antimatter asymmetry in the universe, the smallness of neutrino mass, and the symmetry structure of the Standard Model. My research involves addressing critical challenges on the path to realization of high pressure xenon gas detectors for ton-scale, very low background neutrinoless double beta decay searches. While most aspects of this technology are easily scalable, some …

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