The dominant features of the internet linguistics

This research aims at the modern Internet linguistics features by carrying out linguistic analysis using descriptive statistics of students in distance learning. A linguistic analysis found that most students used lexical, orthographic, paralinguistic, and graphic features when communicating in an online classroom. A total of 452 messages, containing a corpus of 6,340 words, were analyzed and found that only 23.72% of the total corpus was found with lexical, spelling, paralinguistic and graphical features at the Massachusetts Institute of Technology, 22.63% at Stanford University, 21.78% at Harvard University, 24.58% at the California Institute of Technology and 22.76% at Oxford University.

Automated Noise Calibration System (VT-1000)

This paper details an automated Noise Source calibration system in development at Jet Propulsion Laboratory, California Institute of Technology (JPL). The paper begins with a discussion on noise figure and excess-noise-ratio (ENR) theory, fundamentals and governing equations. As part of the fundamentals there is a discussion of the system’s use of the Y-factor method to obtain accurate measurements of the unit under test (UUT), and how these measurements are compared against a known ENR standard to obtain the UUT’s ENR values. There is also an in-depth discussion on uncertainty quantification for noise source system calibrations. The architecture of the automated calibration system is provided, which includes both the system’s hardware and software configuration. The software is written in Python 3, and provides the user detailed instruction on how to proceed, including step-by-step connection requirements. This system automates much of the measurement process, including real-time uncertainty quantification and report generation, as well as real-time feedback to the user to allow intervention. The system takes advantage of a database of results from previous measurements to compare calibration history of the ENR measurements. The automated system presented here operates over a frequency range from 10 MHz to 50 GHz, and has shown substantial time savings over traditional manual methods of performing this calibration

FIRST FINDINGS ON COMETARY ACTIVITY FROM THE PTF COMET SAMPLE

We present preliminary results from the Palomar Transient Factory (PTF) uniform sample of short period comets (SPCs) and long period comets (LPCs), captured between September 2009 and March 2013. We study their dynamical and physical properties in relation to their activity for a better understanding of cometary evolution. This observing campaign was part of PTF in its intermediate phase (iPTF) at the California Institute of Technology (Caltech). The photometric sample comprises more than 180 comets, which makes it one of the largest samples studied to-date. We present a new approach to identifying active comets that compares subtracted aperture magnitudes of comets with the distribution of stars of similar brightness in each image. In this paper, we present initial findings on cometary activity in relationship to their perihelion distances. We show differences between the distributions of the SPCs and that of the LPCs. As others predicted, it seems that a larger fraction of LPCs are found to be active at larger perihelia than for the SPCs. We look at ratios of active comets in different perihelia brackets and compare those to previous works and results. We do not discuss the statistical significance of our findings as this is still work in progress.

An Interview with Nobel Laureate David Baltimore, PhD

In an online interview, Nobel Laureate David Baltimore, Ph.D., reflected on his contributions to biomedical science that have had a major influence on the fields of molecular biology, virology, cancer, and immunology. Dr. Baltimore is President Emeritus and Distinguished Professor of Biology at the California Institute of Technology. Among other notable works, he discovered the critical nuclear transcription factor NF Kappa B and the Rag1 and Rag2 proteins that rearrange adaptive immune cell receptors. His career path, he says, evolved naturally, as math and science came easily to him. As a high school student, he participated in a summer program at the Jackson Lab in Bar Harbor, Maine, where he says he came away feeling that experimental biology was exciting and rewarding. “That's where I discovered that the frontiers of science, were not so distant; that I could actually make a discovery that nobody else in the world knew about,” he says. And that he did. Independently, he and Howard Temin discovered the viral enzyme reverse transcriptase revising the canon of cellular information transfer. They published back-to-back papers in Nature demonstrating that this enzyme in virus particles could transcribe RNA to DNA. Both received a Nobel Prize for this work. In reflecting on his early experience evaluating how to work with recombinant DNA and how we should scientifically and safely approach gain of function research, he says, “We have to be very honest with ourselves about what might hold danger, and we have to control our instinct … to do anything we can to generate progress and understanding of life. …At the same time, we don’t want to hold back progress, and so there is a balancing.” Dr. Baltimore also discussed his optimism about vectored immunoprophylaxis as a strategy for prevention of HIV and his doubt that scalable strategies will be able to cure HIV. He also reflected on his philosophy for the training of young scientists and the successful training program that he developed at the Whitehead Institute.

Realizing the Potential of JWST High Contrast Imaging with Coronagraphic Phase-Retrieval

<div>  The James Webb Space Telescope (JWST) will probe circumstellar environments at an unprecedented sensitivity. However, the performance of high-contrast imaging instruments is limited by the residual light from the star at close separations (<2-3”), where the incidence of exoplanets increases rapidly. There is currently no solution to get rid of the residual light down to the photon noise level at those separations, which may prevent some crucial discoveries.</div> <div>  We are further developing and implementing a potentially game-changing technique of post-processing that does not require the systematic observation of a reference star, but instead directly uses data from the science target by taking advantage of the technique called “phase retrieval”. This technique is built on a Bayesian framework that provides a more robust determination of faint astrophysical structures around a bright source.</div> <div>  This approach uses a model of instrument that takes advantage of prior information, such as data from wavefront sensing operations on JWST, to estimate instrumental aberrations and further push the limits of high-contrast imaging. With this approach, our goal is to improve the contrast that can be achieved with JWST instruments.</div> <div>  We were awarded a JWST GO-Calibration proposal to implement, test and validate this approach on NIRCam imaging and coronagraphic imaging. This work will pave the way for the future space-based high-contrast imaging instruments such as the Nancy Grace Roman Space Telescope Coronagraph Instrument (Roman CGI). This technique will be crucial to make the best use of the telemetry data that will be collected during the CGI operations.</div> <div>  <br />“© 2021 California Institute of Technology. Government sponsorship acknowledged. The research was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. This document has been reviewed and determined not to contain export controlled data.”</div>

Compositional mapping of Titan’s surface using Cassini VIMS and RADAR data

<p>The investigation of Titan’s surface chemical composition is of great importance for the understanding of the atmosphere-surface-interior system of the moon. The Cassini cameras and especially the Visual and infrared Mapping Spectrometer has provided a sequence of spectra showing the diversity of Titan’s surface spectrum from flybys performed during the 13 years of Cassini’s operation. In the 0.8-5.2 μm range, this spectro-imaging data showed that the surface consists of a multivariable geological terrain hosting complex geological processes. The data from the seven narrow methane spectral “windows” centered at 0.93, 1.08, 1.27, 1.59, 2.03, 2.8 and 5 μm provide some information on the lower atmospheric context and the surface parameters. Nevertheless, atmospheric scattering and absorption need to be clearly evaluated before we can extract the surface properties. In various studies (Solomonidou et al., 2014; 2016; 2018; 2019; 2020a, 2020b; Lopes et al., 2016; Malaska et al., 2016; 2020), we used radiative transfer modeling in order to evaluate the atmospheric scattering and absorption and securely extract the surface albedo of multiple Titan areas including the major geomorphological units. We also investigated the morphological and microwave characteristics of these features using Cassini RADAR data in their SAR and radiometry mode. Here, we present a global map for Titan’s surface showing the chemical composition constraints for the various units. The results show that Titan’s surface composition, at the depths detected by VIMS, has significant latitudinal dependence, with its equator being dominated by organic materials from the atmosphere and a very dark unknown material, while higher latitudes contain more water ice. The albedo differences and similarities among the various geomorphological units give insights on the geological processes affecting Titan’s surface and, by implication, its interior. We discuss our results in terms of origin and evolution theories.</p> <p>References: [1] Solomonidou, A., et al. (2014), J. Geophys. Res. Planets, 119, 1729; [2] Solomonidou, A., et al. (2016), Icarus, 270, 85; [3] Solomonidou, A., et al. (2018), J. Geophys. Res. Planets, 123, 489; [4] Solomonidou, A., et al. (2020a), Icarus, 344, 113338; [5] Solomonidou, A., et al. (2020b), A&A 641, A16; [6] Lopes, R., et al. (2016) Icarus, 270, 162; [7] Malaska, M., et al. (2016), Icarus 270, 130; [8] Malaska, M., et al. (2020), Icarus, 344, 113764.</p> <p>Acknowledgements: This work was conducted at the California Institute of Technology (Caltech) under contract with NASA. Y.M. and A.S. (partly) was  supported by the Czech Science Foundation (grant no. 20-27624Y). ©2021 California Institute of Technology. Government sponsorship acknowledged.</p>

НАУКОВЕ ЗАБЕЗПЕЧЕННЯ ПРОЄКТУ «ПРЕЗИДЕНТСЬКИЙ УНІВЕРСИТЕТ»

Представлено візію, місію, ключові особливості Президентського університету, діяльність якого спрямовуватиметься на впровадження ефективних освітніх стратегій для реалізації інтелектуального і творчого потенціалу громадян України, що забезпечить підготовку лідерів для стратегічних галузей розвитку держави, готових до викликів сучасного мінливого світу. Наведено стратегічні цілі для реалізації діяльності університету як сучасного інноваційного освітнього і наукового центру. Висвітлено порівняльні концептуальні характеристики Каліфорнійського інституту технології (California Institute of Technology, Caltech) та майбутнього Президентського університету. Наведено ризики, зумовлені відсутністю законодавчого забезпечення, особливим статусом університету, складністю конкурентних умов з топовими українськими університетами.

The Pransky interview: Dr Gary Guthart, chief executive officer, Intuitive

Purpose The following paper is a “Q&A interview” conducted by Joanne Pransky of Industrial Robot Journal as a method to impart the combined technological, business and personal experience of a prominent, robotic industry turned successful business leader, regarding the commercialization and challenges of bringing technological inventions to market while overseeing a company. This paper aims to discuss these issues. Design/methodology/approach The interviewee is Dr Gary Guthart, Chief Executive Officer (CEO) at Intuitive Surgical, Inc., and a member of the Board of Directors, both roles he has held since 2010. Guthart discusses his journey to becoming the CEO and also shares some of his lessons learned and challenges faced. Findings Guthart received a bachelor’s degree in engineering physics from California, Berkeley. He earned an MS and a PhD in engineering from the California Institute of Technology. Guthart’s first scientific experience came early in his career in a Human Factors Lab at NASA, supporting a team studying human performance assessment of pilots. Guthart was then part of the core team developing foundational technology for computer-enhanced surgery at SRI International. While at SRI, he also developed algorithms for vibration and acoustic control of large-scale systems. Guthart joined Intuitive Surgical as part of the first engineering team in 1996 as a Control Systems Analyst. He was promoted to Vice President of Engineering in 2002 and was appointed President and Chief Operating Officer in 2008. Originality/value Under Dr Gary Guthart’s leadership and his more than 25 years of medical technology, engineering, scientific and management experience, Intuitive Surgical, Inc., the world’s most successful medical robotics company, has grown to: more than 8,000 employees; nearly 6,000 da Vinci systems sold; more than 8.5 million procedures performed and an increase in stock (NASDAQ: ISRG) of more than 600%. Guthart is also on the Board of Directors for Illumina, Inc., and a member of the Board of Directors for the Silicon Leadership Group.

Computer vision model for detecting block falls at the martian north polar region.

<p>Dynamic changes of Martian north polar scarps present a valuable insight into the planet's natural climate cycles (Byrne, 2009; Head et al., 2003)<sup>1,2</sup>. Annual avalanches and block falls are amongst the most noticeable surface processes that can be directly linked with the extent of the latter dynamics (Fanara et al, 2020)<sup>3</sup>. New remote sensing approaches based on machine learning allow us to make precise records of the aforementioned mass wasting activity by automatically extracting and analyzing bulk information obtained from satellite imagery.  Previous studies have concluded that a Support Vector Machine (SVM) classifier trained using Histograms of Oriented Gradients (HOG) can be used to efficiently detect block falls, even against backgrounds with increased complexity (Fanara et al., 2020)<sup>4</sup>. We hypothesise that this pretrained model can now be utilized to generate an extended dataset of labelled image data, sufficient in size to opt for a deep learning approach. On top of improving the detection model we also attempt to address the image co-registration protocol. Prior research has suggested this to be a substantial bottleneck, which reduces the amounts of suitable images. We plan to overcome these limitations either by extending our model to include multi-sensor data, or by deploying improved methods designed for exclusively optical data (e.g.  COSI-CORR software (Ayoub, Leprince and Avouac, 2017)<sup>5</sup>).  The resulting algorithm should be a robust solution capable of improving on the already established baselines of 75.1% and 8.5% for TPR and FDR respectively (Fanara et al., 2020)4. The NPLD is our primary area of interest due to it’s high levels of activity and good satellite image density, yet we also plan to apply our pipeline to different surface changes and Martian regions as well as on other celestial objects.</p><p> </p><p>1. Head, J.W., Mustard, J.F., Kreslavsky, M.A., Milliken, R.E., Marchant, D.R., 2003. Recent ice ages on Mars. Nature 426, 797–802</p><p>2. Byrne, S., 2009. The polar deposits of Mars. Annu. Rev. Earth Planet. Sci. 37, 535–560.</p><p>3. Fanara, K. Gwinner, E. Hauber, J. Oberst, Present-day erosion rate of north polar scarps on Mars due to active mass wasting; Icarus,Volume 342, 2020; 113434, ISSN 0019-1035.</p><p>4. Fanara, K. Gwinner, E. Hauber, J. Oberst, Automated detection of block falls in the north polar region of Mars; Planetary and Space Science, Volume 180, 2020; 104733, ISSN 0032-0633.</p><p>5. Ayoub, F.; Leprince, S.; Avouac, J.-P. User’s Guide to COSI-CORR Co-registration of Optically Sensed Images and Correlation; California Institute of Technology: Pasadena, CA, USA, 2009; pp. 1–49.</p>

Hybrid Architectures with Quantum Gravity Gradiometry and Satellite-to-Satellite Tracking for Spaceborne Mass Change Measurements - A Sensitivity and Performance Analysis

<p>Advances in atom interferometry have led to quantum gravity gradiometer instruments, which have further led to spaceborne mission concepts utilizing this technology to measure Earth’s gravity field and its time variations. The mass changes inferred from gravity change measurements lead to greater understanding of the dynamical Earth system, as demonstrated by GRACE and GRACE Follow-On missions.</p><p>We report the results from a sensitivity and performance assessment study with quantum gradiometers used in two configurations – first as a single-axis gradiometer with a GNSS receiver; and second in a novel hybrid configuration combining cross-track quantum gravity gradiometer and an inter-satellite tracking system. The relative advantages of the two configurations are assessed in terms of their susceptibility to system errors (such as tracking, pointing, or measurement errors), and to modeling errors due to aliasing from rapid time- variations of gravity (so-called “de-aliasing errors”). We evaluate and discuss the impact of de-aliasing errors on gravity fields resulting from the study. We conclude with a specification of the key measurement error thresholds for a notional hybrid gravity field mapping mission.</p><p>Part of the research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).</p><p><span xml:lang="EN-US" data-scheme-color="@7F7F7F,0,18:50000" data-usefontface="false" data-contrast="none"><span>Acknowledgement: UTCSR effort was funded by JPL grant 1656926. Use of resources at the </span></span><span xml:lang="EN-US" data-scheme-color="@7F7F7F,0,18:50000" data-usefontface="false" data-contrast="none"><span>Texas Advanced Computing Center is gratefully acknowledged. </span></span></p>