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Full-Text Articles in Physical Sciences and Mathematics

Advancing The Accuracy Of Watershed Analysis Across Diverse Hydrometeorological And Geologic Regimes Via Classification And Analysis Of Gpm-Imerg Products, Jake M. Longenecker Jan 2023

Advancing The Accuracy Of Watershed Analysis Across Diverse Hydrometeorological And Geologic Regimes Via Classification And Analysis Of Gpm-Imerg Products, Jake M. Longenecker

Dissertations and Theses

The analysis and protection of watersheds, along with spring water resources, depend on the accurate identification of catchments. Building on previous research that correlated spring hydrographs with high-resolution, satellite-based Global Precipitation Measurement – Integrated Multi-satellitE Retrievals for GPM (GPM-IMERG) data, I improve the speed and accuracy of catchment identification and hydrodynamic characterization via an enhanced Empirically Constrained Hydrologic Operation (ECHO) algorithm. This research (1) establishes optimal parameter inputs for the algorithm to enable reliable identification of source point-locations, (2) removes human in-the-loop processing, and thus reduce potential operator bias, and (3) explores the potential for using a limited dataset of …


Molecular Elucidation Of Reaction Mechanisms In Aluminum & Lithium Metal Batteries By Solid-State Nmr Spectroscopy And Electrochemical Methods, Leo W. Gordon Jan 2023

Molecular Elucidation Of Reaction Mechanisms In Aluminum & Lithium Metal Batteries By Solid-State Nmr Spectroscopy And Electrochemical Methods, Leo W. Gordon

Dissertations and Theses

As society wrestles with the ever-growing climate consequences of burning fossil fuels, the increased demand for electric vehicles and renewable power generation mandates safe, sustainable, earth-abundant, low cost, and energy dense batteries. Different use cases will necessitate different types of batteries; for example, stationary storage systems prioritize minimal expense, whereas mobile applications like electric vehicles emphasize high energy densities. Aluminum and lithium metal batteries hold great promise for next-generation energy storage due to their large specific capacities (2980 mA h g-1, and 3860 mA h g-1, respectively). In particular, aluminum metal is low cost, has high …


Machine Learning Approach To Predict Tdcs-Induced Electric Current In The Human Brain, Chikako Olsen Jan 2023

Machine Learning Approach To Predict Tdcs-Induced Electric Current In The Human Brain, Chikako Olsen

Dissertations and Theses

Background: Transcranial direct current stimulation (tDCS) is a promising non-invasive method for treating neurological and psychiatric disorders and enhancing cognitive function. However, the underlying mechanisms of tDCS are not fully understood, and there is no ground truth for determining, non-invasively, where in the brain tDCS electrical currents flow. At the same time, effective neuronal engagement from tDCS requires accurate localization of the induced currents to specific brain target regions. Machine Learning (ML) has the potential to significantly improve the accuracy and precision of tDCS current prediction. This study aims to develop a novel approach using ML to predict the location …


Analysis Of Chemical Elements In Basalts Using Mislabeled Data, A Machine Learning Approach, Jenifer Vivar Jan 2023

Analysis Of Chemical Elements In Basalts Using Mislabeled Data, A Machine Learning Approach, Jenifer Vivar

Dissertations and Theses

Scientists use basalt chemistry to discriminate among different tectonic settings. There are well-known chemical elements used to classify tectonic settings. An exploration of new features is done using Logistic Regression and Random Forest to discover any new elements of interest. The models were used with other tools, such as recursive feature elimination and permutations, to increase reliability. Among the scarcely explored chemical elements are Terbium (Tb), Holmium (Ho), Samarium (Sm), and Erbium (Er). The data used for the exploration contained many outliers. Therefore, an ensemble model was created to explore the location and composition of such outliers. The ensemble was …


Exploring Information Leakage In Historical Stock Market Data, Edison Hua Jan 2023

Exploring Information Leakage In Historical Stock Market Data, Edison Hua

Dissertations and Theses

Information leakage is a major concern for traders who want to execute large orders without affecting the market price. In this paper, we explore the sources and effects of information leakage in historical stock market data using various methods and metrics. We first define information leakage as a pattern caused by a trader that would otherwise not occur without the trader’s activity. Using historical data, the direct impact of a potential large trade cannot be measured, but we consider a minimal impact large trade to be one that minimizes changes to the established trading data. We then analyze how information …


Anomaly Based Intrusion Detection System Through Remote Virtual Machine Introspection, Huseyn Huseynov Jan 2023

Anomaly Based Intrusion Detection System Through Remote Virtual Machine Introspection, Huseyn Huseynov

Dissertations and Theses

Research on identifying malicious applications is an important direction in information security, especially when it comes to detection of evasive malware such as keyloggers, trojans, rootkits and their derivatives. Inspired by a biological immune system and based on negative selection algorithm approach to detect various types of malwares is proposed in this paper.

By deeply studying Linux kernel, understanding links behind different internal system processes, examining, and experimenting with hundreds of various keyloggers we propose a single Artificial Intelligence based solution as a comprehensive protection against wide range of malwares. Developed Intrusion Detection System (IDS) can be deployed in the …


Optimization Of Optical Nanosensor Response For The Detection Of Anthracyclines Using A Binary Machine Learning Classifier, Myesha Thahsin Jan 2023

Optimization Of Optical Nanosensor Response For The Detection Of Anthracyclines Using A Binary Machine Learning Classifier, Myesha Thahsin

Dissertations and Theses

Pharmacokinetic variables such as interindividual variation in metabolizing and eliminating drugs makes dose selection of chemotherapeutic anthracyclines difficult. One potential solution to determining dosing levels of an anthracycline is the development of non-invasive sensors to monitor their pharmacology in vivo. Single-walled carbon nanotubes (SWCNT) have substantial potential for in vivo sensor development, as they exhibit near-infrared fluorescence in the tissue-transparent window and a robust response to their local environment. An emerging method for evaluating and optimizing SWCNT sensor response is through machine learning. In this study, anthracyclines Daunorubicin, Doxorubicin, Epirubicin, Mitoxantrone and Idarubicin, were used to interrogate 12 SWCNT preparations …


Shallow Water Coral Distribution And Its Response To Climate Change, Amaury De Jesus Jan 2023

Shallow Water Coral Distribution And Its Response To Climate Change, Amaury De Jesus

Dissertations and Theses

Shallow water corals are one of the main reef-building organisms that secrete carbonates as their skeletons, and therefore, are one of the major sinks of CO2 in the ocean. These reef builders are also very crucial to marine environments and human society. As the global energy demand continues rising, fossil fuel burning increases at a faster pace despite the increase in energy supply using clean and renewable energy. The increase of CO2 in the atmosphere has been shown to exacerbate global warming and may cause ocean acidification, threatening the habitat of shallow-water corals. Many recent observations show alarming signs of …


Impact Melt Rocks From The Late Paleocene Hiawatha Impact Structure, Northwest Greenland, William R. Hyde, Adam A. Garde, Nynke Keulen, Sebastian N. Malkki, Steven J. Jaret, Tod Waight, Pierre Beck, Iain Mcdonald, Nicolaj K. Larsen Jan 2023

Impact Melt Rocks From The Late Paleocene Hiawatha Impact Structure, Northwest Greenland, William R. Hyde, Adam A. Garde, Nynke Keulen, Sebastian N. Malkki, Steven J. Jaret, Tod Waight, Pierre Beck, Iain Mcdonald, Nicolaj K. Larsen

Publications and Research

Impact melt rocks formed during hypervelocity impact events are ideal for studying impact structures. Here, we describe impact melt rock samples collected proximal to the 31 km wide 58 Ma Hiawatha impact structure, northwest Greenland, which is completely covered by the Greenland Ice Sheet. The melt rocks contain diagnostic shock indicators (e.g., planar deformation features [PDF] in quartz and shocked zircon) and form three groups based on melt textures and chemistry: (i) hypocrystalline, (ii) glassy, and (iii) carbonate-based melt rocks. The exposed foreland directly in front of the structure consists of metasedimentary successions and igneous plutons; however, the carbonate-based impactites …


Cp6200 Javaprogramming2 Oer - Oop Assignment - Item And Shopping Cart Classes, Shoshana Marcus Jan 2023

Cp6200 Javaprogramming2 Oer - Oop Assignment - Item And Shopping Cart Classes, Shoshana Marcus

Open Educational Resources

No abstract provided.


Active Learning For Efficient Soil Monitoring In Large Terrain With Heterogeneous Sensor Network, Hui Chen, Ju Wang Jan 2023

Active Learning For Efficient Soil Monitoring In Large Terrain With Heterogeneous Sensor Network, Hui Chen, Ju Wang

Publications and Research

Soils are a complex ecosystem that provides critical services, such as growing food, supplying antibiotics, filtering wastes, and maintaining biodiversity; hence monitoring soil health and domestication is required for sustainable human development. Low-cost and high-resolution soil monitoring systems are challenging to design and build. Compounded by the sheer size of the monitoring area of interest and the variety of biological, chemical, and physical parameters to monitor, naive approaches to adding or scheduling more sensors will suffer from cost and scalability problems. We investigate a multi-robot sensing system integrated with an active learning-based predictive modeling technique. Taking advantage of advances in …


Perspectives On Determinism In Quantum Mechanics: Born, Bohm, And The “Quantal Newtonian” Laws, Viraht Sahni Dec 2022

Perspectives On Determinism In Quantum Mechanics: Born, Bohm, And The “Quantal Newtonian” Laws, Viraht Sahni

Publications and Research

Quantum mechanics has a deterministic Schrödinger equation for the wave function. The Göttingen–Copenhagen statistical interpretation is based on the Born Rule that interprets the wave function as a “probability amplitude.” A precept of this interpretation is the lack of determinism in quantum mechanics. The Bohm interpretation is that the wave function is a source of a field experienced by the electrons, thereby attributing determinism to quantum theory. In this paper, we present a new perspective on such determinism. The ideas are based on the equations of motion or “Quantal Newtonian” Laws obeyed by each electron. These Laws, derived from …


Methods For Drone Trajectory Analysis Of Bottlenose Dolphins (Tursiops Truncatus), Jillian D. Bliss Dec 2022

Methods For Drone Trajectory Analysis Of Bottlenose Dolphins (Tursiops Truncatus), Jillian D. Bliss

Theses and Dissertations

With the increase in the use of UAS (Unmanned Aerial Systems) for marine mammal research, there is a need for the development of methods of analysis to transform UAS high resolution video into quantitative data. This study sought to develop a preliminary method of analysis that would quantify and present a way to visualize the dynamics and relative spatial distribution and changes in distribution of bottlenose dolphins (Tursiops truncatus) in the waters of Turneffe Atoll, Belize. This approach employs a previously developed video tracking program ‘Keypoint Tracking’ that enables manual tracking of individual dolphins and the creation of …


Classical Mechanics, Mark D. Shattuck Dec 2022

Classical Mechanics, Mark D. Shattuck

Open Educational Resources

Syllabus for Classical Mechanics


Secondhand Shopping Is Now The Coolest Way To Get Your Clothes, Camryn Quick Dec 2022

Secondhand Shopping Is Now The Coolest Way To Get Your Clothes, Camryn Quick

Capstones

Shopping secondhand has experienced an uptick in popularity in the past few years. There are a few reasons for this, all of which are examined in the project. One reason for the increase in secondhand shoppers is the daunting news about the state of our environment. Another reason, perhaps even more powerful than the fear of environmental collapse, is that thrifting has become a fashion phenomenon showcased and distributed throughout social media apps like TikTok. Essentially, shopping secondhand has become cool. This project explores these driving forces behind the thrifting boom, as well as the possible impacts, including "thrift store …


To Destroy Or Transform? Two Fossil Fuel Transitions Offer Glimpse Into Industry’S Future, Chloe Bennett, Sarah Kerson Dec 2022

To Destroy Or Transform? Two Fossil Fuel Transitions Offer Glimpse Into Industry’S Future, Chloe Bennett, Sarah Kerson

Capstones

In 2019, the Philadelphia Energy Solutions oil refinery closed after a dangerous explosion. But for years before the accident, members of the local environmental justice organization Philly Thrive had been advocating for its closure. Neighborhood residents who live near the refinery site had been complaining for years of health problems, ranging from asthma to cancer. “Enough is enough,” says Sylvia Bennett, 79, who lives in the Grays Ferry neighborhood near where the refinery is located. Her two daughters have both been diagnosed with cancer.

What will become of the refinery site remains to be seen as conversations between Hilco and …


Temporal Optical Activity And Chiral Time-Interfaces [Invited], Shixiong Yin, Yao-Ting Wang, Andrea Alù Dec 2022

Temporal Optical Activity And Chiral Time-Interfaces [Invited], Shixiong Yin, Yao-Ting Wang, Andrea Alù

Advanced Science Research Center

Time-interfaces, at which the optical properties of a medium undergo abrupt and spatially uniform changes, have attracted surging interest in optics and wave physics. In this work, we study wave scattering at time-interfaces involving chiral media. Dual to spatial interfaces involving chiral media, we show that a propagating wave is split upon a chiral time-interface into two orthogonal circular polarization waves oscillating at different frequencies. We formulate the temporal scattering boundary-value problem at such time-interfaces, and then demonstrate the effect of temporal optical activity through a chiral time-slab. The effect of material dispersion is also analyzed, highlighting interesting opportunities in …


Scientists And Activists Work To Save The Planet, Myriam G. Vidal Valero Dec 2022

Scientists And Activists Work To Save The Planet, Myriam G. Vidal Valero

Capstones

Climate change and human intervention in nature are affecting people, ecosystems and ways of living all over the world. This portfolio of environmental pieces showcases the dire consequences of not addressing these issues, how solutions can be reached and the challenges facing those who try to change things.


High Resolution Modeling Of Vegetation Reveals Large Summertime Biogenic Co2 Fluxes In New York City, Dandan Wei, Andrew Reinmann, Luke D. Schiferl, Roisin Commane Dec 2022

High Resolution Modeling Of Vegetation Reveals Large Summertime Biogenic Co2 Fluxes In New York City, Dandan Wei, Andrew Reinmann, Luke D. Schiferl, Roisin Commane

Advanced Science Research Center

Cities are beginning to monitor atmospheric carbon dioxide (CO2) to assess the efficacy of their climate policies. However, changes in anthropogenic CO2 emissions must be separated from biospheric CO2 fluxes which have a large seasonal cycle. Urban vegetation (e.g. lawns, trees along street and in parks, etc) in developed land covers is often omitted in regional biogenic CO2 flux models. We set up a biosphere model to estimate the regional biogenic CO2 fluxes in New York City (NYC) and assess the importance of vegetation within developed land covers. The model incorporates a high-resolution (30 …


Sea Level Rising And Its Impact On Nyc, Angela Knafo, Jeff Mao, Andray Whyte, Filip Valencin, Erick Humala, Jubran Alawdi, Jonathan Carangui Dec 2022

Sea Level Rising And Its Impact On Nyc, Angela Knafo, Jeff Mao, Andray Whyte, Filip Valencin, Erick Humala, Jubran Alawdi, Jonathan Carangui

Publications and Research

Climate change is not only about the rising temperatures, which is usually the most discussed topic in news, but it also involves other Earth sciences like hydrology, oceanography and other parts of meteorology In our poster we are focusing on sea level rising and its impact on NYC, and how people could mitigate and adapt to it


From Computer Curriculum That Works For The Use Of Computer Intellignece Computer Science, Malachi B. Bacchus Dec 2022

From Computer Curriculum That Works For The Use Of Computer Intellignece Computer Science, Malachi B. Bacchus

Publications and Research

Computer interconnection can link different networks by using electrical artificial flow ways that can travel through different connections. these are called data network which travels through different sectors of the network simulation of service computer network using artificial intelligence to enhanced further understanding the computations, I've also demonstrated knowing by using the network to get better understanding of how ethical computing can be learned through universities and collegiate that can help established knowledge and healthy computer information. The main tools for the research are using data networking, ethical learning and translation towards different computer systems.


Computer Ethics In Curriculum, Tiya Williams Dec 2022

Computer Ethics In Curriculum, Tiya Williams

Publications and Research

Ethics specifically in Computer Curriculum is a growing problem that has yet to be widely addressed. Although, start of computer ethics being taught has been traced back to the early 1940’s it has not been standardized or implemented in all computer curriculum. The objective of this research is to diagnose the reasons why ethics is so crucial in computer curriculum at all levels. I used surveys to investigate whether students were taught ethics in their computer curriculum. I also conducted surveys for professors at universities and colleges if they were taught ethics while obtaining their degree, as well as if …


The Living Breakwaters Pdr Efforts Econcrete Resource Analysis, Guianina Ferrari, Shervon Stephens, Calvin O. Walters Jr. Dec 2022

The Living Breakwaters Pdr Efforts Econcrete Resource Analysis, Guianina Ferrari, Shervon Stephens, Calvin O. Walters Jr.

Publications and Research

On October 29, 2012, Superstorm Sandy impacted 443,000 people and caused nearly $19 billion (about $58 per person in the US) worth of damage within New York City. As part of the New York City infrastructure reparation plan, the Living Breakwaters project in Tottenville addressed coastal resilience, allocating $100M of public funds to a series of artificial breakwaters by the southwest coast of Staten Island. Each breakwater is constructed and designed to mitigate water flow in storm events. ECOncrete, a primary element of the breakwater, is a specialty cast cementitious product that is marine organism-friendly that encourages biocalcification and photosynthesis. …


Systematic Review Of A Ramsar Wetland And Unesco Biosphere Reserve In A Climate Change Hotspot (Ichkeul Lake, Tunisia), Sabrine Sahbani, Béchir Béjaoui, Sihem Benabdalla, Rachid Toujani, Afef Fathalli, Noureddine Zaaboub, Jalel Aouissi, Zeineb Kassouk, Nabil Hamdi, Nabiha Ben Mbarek, Hechmi Missaoui, Leila Basti, Reginald Blake, Hamidreza Norouzi Dec 2022

Systematic Review Of A Ramsar Wetland And Unesco Biosphere Reserve In A Climate Change Hotspot (Ichkeul Lake, Tunisia), Sabrine Sahbani, Béchir Béjaoui, Sihem Benabdalla, Rachid Toujani, Afef Fathalli, Noureddine Zaaboub, Jalel Aouissi, Zeineb Kassouk, Nabil Hamdi, Nabiha Ben Mbarek, Hechmi Missaoui, Leila Basti, Reginald Blake, Hamidreza Norouzi

Publications and Research

Tunisia's Ichkeul Lake is among the most productive ecosystems in the Mediterranean, with a great regional value thanks to its diversity of habitats. It is an important overwintering area for waterfowl species. It is a RAMSAR wetland, a National Park, a UNESCO World Heritage, and a Biosphere Reserve. This review paper provides a broad overview of the climatic, hydraulic, biogeochemical features, bio-resources, and bio-productivity of the Lake. The interconnectivity between the different environmental components of the lake is presented, highlighting the main characteristics of this vital ecosystem. Its ecosystem consists of a permanent lake bordered by temporary marshes. It is …


Natural Language Processing For Disaster Tweets, Akinyemi D. Apampa, Nan Li Dec 2022

Natural Language Processing For Disaster Tweets, Akinyemi D. Apampa, Nan Li

Publications and Research

Our goal is to establish an automatic model that identifies which tweets are about natural disasters based on the content of the tweets. Our method is to construct a decision tree based on keyword searching. We will construct the model using 7,645 tweets and test our model on 3,465 tweets as an assessment of the performance.


Coupled Spherical-Cavities, Stanislav Kreps, Vladimir Shuvayev, Mark Douvidzon, Baheej Bathish, Tom Lenkiewicz Abudi, Amirreza Ghaznavi, Jie Xu, Yang Lin, Lev Deych, Tal Carmon Dec 2022

Coupled Spherical-Cavities, Stanislav Kreps, Vladimir Shuvayev, Mark Douvidzon, Baheej Bathish, Tom Lenkiewicz Abudi, Amirreza Ghaznavi, Jie Xu, Yang Lin, Lev Deych, Tal Carmon

Publications and Research

In this work, we study theoretically and experimentally optical modes of photonic molecules—clusters of optically coupled spherical resonators. Unlike previous studies, we do not use stems to hold spheres in their positions relying, instead on optical tweezers to maintain desired structures. The modes of the coupled resonators are excited using a tapered fiber and are observed as resonances with a quality factor as high as 107. Using the fluorescent mapping technique, we observe families of coupled modes with similar spatial and spectral shapes repeating every free spectral range (a spectral separation between adjacent resonances of individual spheres). Experimental results are …


Editorial: Advances In Phononic And Acoustic Metamaterials, Yu-Gui Peng, Simon Yves, Ying Li Nov 2022

Editorial: Advances In Phononic And Acoustic Metamaterials, Yu-Gui Peng, Simon Yves, Ying Li

Advanced Science Research Center

The quasi-particle linked to mechanical vibration, namely the phonon, is responsible for everyday sound and heat transmission in air, water and other media. Hence, investigating and controlling the phononic properties of materials provides new opportunities and powerful tools to tailor acoustic wave propagation and heat transport. During the past few decades, there has been considerable interest in studying theoretically and experimentally the acoustic, elastodynamic and thermal properties of artificial media made of small inclusions. These metamaterials are engineered to exhibit exotic properties beyond what naturally occurs in materials, including negative bulk-modulus, zero/negative density and infinite thermal conductivity. Many tantalizing concepts …


Whispering Gallery Modes Of A Triatomic Photonic Molecule, Vladimir Shuvayev, Stanislav Kreps, Tal Carmon, Lev Deych Nov 2022

Whispering Gallery Modes Of A Triatomic Photonic Molecule, Vladimir Shuvayev, Stanislav Kreps, Tal Carmon, Lev Deych

Publications and Research

In this paper, we present the results of numerical simulations of the optical spectra of a three-sphere photonic molecule. The configuration of the system was continuously modified from linear to triangular, in-plane with the fundamental mode excited in one of the spheres and perpendicular to it. We found the relative insensitivity of the spectra to the in-plane deviation from the linear arrangement up to about 110°. For larger angles, the spectra show significant modification consisting of the major spectral peaks splitting and shifting. On the contrary, the spectra are quite sensitive to out-of-plane molecule deviation, even at small angles. Thus, …


Plasmon Damping Rates In Coulomb-Coupled 2d Layers In A Heterostructure, Dipendra Dahal, Godfrey Gumbs, Andrii Iurov, Chin-Sen Ting Nov 2022

Plasmon Damping Rates In Coulomb-Coupled 2d Layers In A Heterostructure, Dipendra Dahal, Godfrey Gumbs, Andrii Iurov, Chin-Sen Ting

Publications and Research

The Coulomb excitations of charge density oscillation are calculated for a double-layer heterostructure. Specifically, we consider two-dimensional (2D) layers of silicene and graphene on a substrate. From the obtained surface response function, we calculated the plasmon dispersion relations, which demonstrate how the Coulomb interaction renormalizes the plasmon frequencies. Most importantly, we have conducted a thorough investigation of how the decay rates of the plasmons in these heterostructures are affected by the Coulomb coupling between different types of two- dimensional materials whose separations could be varied. A novel effect of nullification of the silicene band gap is noticed when graphene is …


Ammonium Adduct Chemical Ionization To Investigate Anthropogenic Oxygenated Gas-Phase Organic Compounds In Urban Air, Peeyush Khare, Jordan E. Krechmer, Jo E. Machesky, Tori Hass-Mitchell, Cong Cao, Junqi Wang, Francesca Majluf, Felipe Lopez-Hilfiker, Sonja Malek, Will Wang, Karl Seltzer, Havala O. T. Pye, Roisin Commane, Brian C. Mcdonald, Ricardo Toledo-Crow, John E. Mak, Drew R. Gentner Nov 2022

Ammonium Adduct Chemical Ionization To Investigate Anthropogenic Oxygenated Gas-Phase Organic Compounds In Urban Air, Peeyush Khare, Jordan E. Krechmer, Jo E. Machesky, Tori Hass-Mitchell, Cong Cao, Junqi Wang, Francesca Majluf, Felipe Lopez-Hilfiker, Sonja Malek, Will Wang, Karl Seltzer, Havala O. T. Pye, Roisin Commane, Brian C. Mcdonald, Ricardo Toledo-Crow, John E. Mak, Drew R. Gentner

Advanced Science Research Center

Volatile chemical products (VCPs) and other non-combustion-related sources have become important for urban air quality, and bottom-up calculations report emissions of a variety of functionalized compounds that remain understudied and uncertain in emissions estimates. Using a new instrumental configuration, we present online measurements of oxygenated organic compounds in a US megacity over a 10 d wintertime sampling period, when biogenic sources and photochemistry were less active. Measurements were conducted at a rooftop observatory in upper Manhattan, New York City, USA using a Vocus chemical ionization time-of-flight mass spectrometer, with ammonium (NH as the reagent ion operating at 1 Hz. The …