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A technology revolution in Earth observation sensor design is occurring. This revolution in part is associated with the emergence of CubeSat platforms that have forced a de facto standardization on the volume and power into which sensors have to fit. The extent that small sensors can indeed provide similar or replacement capabilities compared to larger and more expensive counterparts has barely been demonstrated and any loss of capability of smaller systems weighed against the gains in costs and new potential capabilities offered by implementing them with a more distributed observing strategy also has not yet been embraced. This paper provides four examples of observations made with prototype miniaturized observing systems, including from CubeSats, that offer a glimpse of this emerging sensor revolution and a hint at future observing system design.

We are on the threshold of a new era in robotic exploration of our solar system, one in which CubeSats and SmallSats will play an important role. As the National Aeronautics and Space Administration (NASA)’s lead center for robotic solar system exploration, JPL has a strategic interest in these new capabilities that enable planetary scientists to expand our knowledge of how our solar system formed, how it works, and even how life originated. In November 2018, JPL’s two Mars Cube One (MarCO) spacecraft, launched with the InSight Discovery mission, made history as they flew past Mars. This first pair of interplanetary CubeSats navigated their way independently to Mars to provide a relay capability for the InSight lander back to Earth. Lunar Flashlight and Near-Earth Asteroid Scout, two CubeSats that are currently under development, will form part of the ‘swarm’ of CubeSats escorted onto a lunar trajectory by NASA’s Artemis-1 mission—the first launch of its new Space Launch System (SLS) rocket. This paper provides an overview of these and other CubeSat and SmallSat mission developments at JPL from the author’s perspective. It is intended to inspire others to follow the trail blazed by these pioneering missions.

Miniaturized and highly capable science instruments are being developed for CubeSats at an increasing rate. These instruments have enabled significant, if niche, science to be performed by CubeSats in the areas of Earth remote sensing, astrophysics, space physics, and soon to include planetary science. CubeSat instruments now available and proven include infrared spectrometers, a variety of radiometers, magnetometers, radar for bistatic radar studies (relatively) high-resolution optical imagers, highly sensitive photometers, Lidar, field and particle sensors, and neutron spectrometers. Development of these instruments has been facilitated by a variety of evolving technologies leading to miniaturization, lower mass, low power consumption, and excellent capabilities. These capable new CubeSat instruments are starting to support applications and missions that were once the realm of large, extremely expensive spacecraft systems. A survey and overview of these instruments is provided along with an assessment of their impact and a brief projection of a vision for future development and related science missions.

The launch and successful operation of the Mars Cube One (MarCO) CubeSats in May of 2018 ushered in a new era of solar system exploration. The 13 interplanetary CubeSats slated to fly on Artemis 1 in 2020 along with MarCO represent the beginning of a new paradigm of planetary exploration—one that utilizes the CubeSat form factor as both primary and supporting exploration platforms. Enabling technologies required by interplanetary CubeSats including relatively high Δv propulsion systems, capable high-frequency transponders, radiation-tolerant components, and extremely capable miniaturized science instruments are now becoming commercially available making these missions possible. Interplanetary CubeSats require different and more sophisticated spacecraft systems architectures and must utilize different and more sophisticated ground station systems than LEO missions. These differences are discussed in this chapter in detail, using specific examples from current and planned missions.

This article seeks to explore factors responsible for the adoption of online marketing by second hand (used) car dealers to sellers in Ghana. A conceptual framework was adopted from the extant literature using the Technology Acceptance Model as a theoretical base. This article adopts a quantitative research approach. Data for the study was obtained from 60 second hand car sellers through a self-administered questionnaire. Findings from this study revealed that factors responsible for online marketing adoption by second hand car dealers in Ghana are: perceived usefulness (marketing online, customer demand and increase productivity; ease of use (ability to upload pictures, interaction with clients, and online vehicles sales) of the platform. The study however, found no significant relationship between IT knowledge of the owner/manager, age of business and adoption of the online technology. This article highlights the importance of technology adoption in business among SMEs from technologically disadvantaged market.

NASA is a dynamic and living organization. Looking at it through the optics of cybernetics, we can describe it as an autopoietic system. It has to sustain itself, and compete successfully to be viable. Its organizational elements have to interact with the broader environment by maintaining and improving its processes that generate the means for future sustainability. It also needs to bring up follow-on generations who are not simply aligning with the status quo, but also improve the system's viability. For government-run programs, organizational, programmatic and project management practices are often rigidly linear. They can be characterized as observed first-order cybernetic systems, where the paradigm is bound by well-established requirements. At the implementation level this does not readily accommodate flexibility and change. To address this, broadening the system's worldview is needed from the strategic level. This corresponds to an observing second-order cybernetic system, where strategic leadership can overwrite the rules of a first-order system. Changing the worldview of an organization can be complex and face much resistance. Still, with the appropriate strategic-level support, it can be achieved by introducing novel languages, new perspectives, and adding new disciplines to existing ones. In effect, this helps to broaden the organizational paradigm, and subsequently influence its mission, impact the culture, and open up its core processes. These changes can be effectively introduced through design conversations in the early formulation stages, when new ideas are conceived. Within NASA's Jet Propulsion Laboratory, early-stage concept developments are performed at a specially formulated environment, called the Innovation Foundry. Within this office, a continuous effort is being made on designing the design processes, which helps to broaden the variety of the option trades. It is achieved by an added focus on conversations and the inclusion of non-engineering disciplines, such as industrial and graphic design, human centered design, and even art. Communicating the information more effectively through conversations and symbolic means benefits from the skills of human centered designers and artists. In this paper we will discuss how design is being designed at JPL's Innovation Foundry, by focusing on novel languages, storytelling, conversations, boundary objects in support of improved communications both externally to stakeholders and sponsors, and internally within the design teams. We will also highlight how these new design driven approaches provide a strategic strength for the organization when competing for funding in a resource-constrained environment.

Introduction In 2016, providers within an Academic Medical Center's Blood and Marrow Transplant (BMT) program recognized preventable readmissions related to missed opportunities in the hospital discharge process. In an effort to address discharge deficiencies and reduce readmissions, Transitional Care Management (TCM) was developed and implemented by BMT Transplant Coordinators in 2017. Methods Hospital discharge reports are generated in the electronic medical record (EMR). Communication within the EMR is sent to the clinical teams the business day following discharge with instruction to initiate a telephone encounter. The clinical team completes a telephone encounter in the EMR and documents review of discharge summary, medications, follow-up appointments, pertinent clinical trial review (if applicable), and symptoms following discharge. Results Retrospective analysis of readmission rates for patients with hematologic malignancies for the period of January 1, 2016, through December 31, 2018, show a decline in readmission rates since implementation of TCM. (30 day- 2016 25.11% vs 2018 23.89%, 14 day 18.14% vs 2018 16.39%, 7 day 2016-13.5% vs 2018 9.6%) Retrospective analysis of TCM completion by BMT coordinators for the period of January 1, 2017 through August 31, 2019, reveal a drastic improvement. Compliance of TCM documentation and completion averaged 88% in 2017, and 85% in 2018. Since utilization of EMR generated telephone encounter notification, 98% completion of the TCM process has been documented. Conclusion TCM has improved quality of care for patients with hematologic malignancies. BMT 30-day, 14-day and 7-day readmission rates have improved since TCM. Utilization of the transplant center's upgraded EMR improved functionality and increased compliance of the TCM documentation process.

Topic Significance & Study Purpose/Background/Rationale A Blood & Marrow Transplant [BMT] program incorporated Medical Assistants [MA's] onto the core clinical teams to perform essential functions. Their role augments interdisciplinary care coordination of ancillary and support services. Methods, Intervention, & Analysis MA were assigned onto interdisciplinary teams, typically consisting of a Medical Oncologist, Advanced Practice Providers, and Transplant Nurse Coordinators. Our MA's also work in conjunction with and as an extension of our Social Work team. Under the guidance of this team, the MA carries out functions including but not limited to: scheduling patients, appointments for visits, testing, referrals, telephone calls, and medications. Findings & Interpretation The addition of MAs onto the clinical teams alleviates workloads for the Transplant Coordinators, allowing their focus to shift to a more patient-centered care model. With the further development of oral chemo and targeted therapies, MAs can spend time working on initiating these therapies and addressing barriers. These therapies typically require insurance prior authorization or applications for patient assistance programs for unaffordable out-of-pocket. Often, MAs help provide these services for patients that are also admitted. This frees up nurses to focus on direct patient issues. Discussion & Implications The complexity of the BMT environment necessitates innovation. Utilizing MAs in this environment streamlines processes to provide comprehensive healthcare to our patients. Development of the MAs in this program leans on the full scope of their practice, while requiring more focused, specialized professional development. With the success of their integration in the outpatient environment, their unique skillset may present an opportunity to help with inpatient care coordination.

The Jet Propulsion Laboratory (JPL) is NASA’s lead center for robotic exploration of our solar system. We are known for our large, flagship missions, such as Voyager, which gave humanity its first close look at Jupiter and Saturn; and the Mars Rovers, which have excited millions worldwide with their daring landing exploits. Less familiar to those outside NASA may be our role in developing the Kepler mission, which has discovered more than 2000 planets around other stars; or the recently launched Soil Moisture Active Passive (SMAP) mission, one of many JPL Earth Science missions. A recent JPL initiative has emphasized low cost missions that use rapidly evolving technology developed for cubesats and nanosats to explore our solar system. Costs are significantly lower (by one or two orders of magnitude) than for conventional JPL missions, and development time is also significantly shorter. At present 21 such cubesat flight projects are under way at the laboratory with various partners: some in flight, some in development, some in advanced formulation. Four are planned as deep space missions. To succeed in exploring deep space cubesat/nanosat missions have to address several challenges: the more severe radiation environment, communications and navigation at a distance, propulsion, and packaging of instruments that can return valuable science into a compact volume/mass envelope. Instrument technologies, including cameras, magnetometers, spectrometers, radiometers, and even radars are undergoing miniaturization to fit on these smaller platforms. Other key technologies are being matured for smallsats and nanosats in deep space, including micro-electric propulsion, compact radio (and optical) communications, and onboard data reduction. This paper will describe missions that utilize these developments including the first two deep space cubesats (INSPIRE), planned for launch in 2017; the first pair of cubesats to be sent to another planet (MARCO), manifested with the InSight Mars lander launch in March of 2016; a helicopter “drone” on Mars to extend the reach of future rovers; plans for a Lunar Flashlight mission to shine a light on the permanently shadowed craters of the Moon’s poles; a Near Earth Asteroid cubesat mission; and a cubesat constellation to demonstrate time series measurements of storm systems on Earth. From these beginnings, the potential for cubesats and nanosats to add to our knowledge of the solar system could easily grow exponentially. Imagine if every deep space mission carried one or more cubesats that could operate independently (even for a brief period) on arrival at their target body. At only incremental additional cost, such spacecraft could go closer, probe deeper, and provide science measurements that we would not risk with the host spacecraft. This paper will describe examples including a nanosat to probe the composition of Venus’ atmosphere, impactors and close flybys of Europa, lunar probes, and soft landers for the moons of Mars. Low cost access to deep space also offers the potential for independent cubesat/nanosat missions – allowing us to characterize the population of near Earth asteroids for example, deploy a constellation around Venus, or take closer looks at the asteroid belt.

Twenty-five years ago, the two flights of the SIR-C/X-SAR Synthetic Aperture Radar (SAR) system on the Space Shuttle Endeavour blazed a trail towards the future with a series of radar system innovations — that nearly every spaceborne SAR flown since then has benefited from, and in some cases improved upon. Many of the SAR techniques adopted by SAR system designers worldwide as part of their toolkit, such as: ScanSAR, Spotlight mode, along-track interferometry, polarization diversity and polarimetry, polarimetric calibration, variable length and bandwidth pulses, and on-board processing, can trace their heritage back to this first-of-a-kind, civil-use SAR system. The electronic steering capability of SIR-C's phased array antenna, combined with the exquisite orbit track control provided by the Space Shuttle, paved the way for systematic mapping of the Earth's topography by the Shuttle Radar Topography Mission, and later by TanDEM-X. Some techniques, such as multi-frequency SAR, multi-frequency repeat-pass interferometry and onboard processing have yet to be fully exploited. The richness of the SIR-C/X-SAR data set has proved to be a treasure trove for opening up entirely new remote sensing techniques, such as Polarimetric SAR Interferometry (or PolInSAR), and GPS, now GNSS, reflections (also known as Signals of Opportunity), which were both demonstrated from archive data, years after the 1994 flights. The ground-breaking legacy of SIR-C/X-SAR lives on in the many SAR systems collecting data in Earth orbit today, and in those planned for the future.

Conventional quadrature-polarimetric (quad-pol) synthetic aperture radar (SAR) systems operating from space are severely constrained by their limited range of useful incident angles and their reduced swath widths particularly at larger incidence. These limitations are due primarily to relatively severe range ambiguities in the cross-polarized measurement channels. The conventional approach for quad-pol SAR systems uses linear polarizations on both transmit and receive. Range ambiguities can be markedly reduced by adopting hybrid-polarimetric architecture. In this approach, the radar transmits circularly polarized waves but receives on orthogonal linear polarizations. The sense of the circular polarization-left or right-is reversed on alternate transmissions. Hybrid-polarimetric quad-pol architecture leads to hardware that is more readily calibrated because neither receive channel is cross polarized with respect to the transmitted polarization; hence, their mean signal levels are the same. The data provided by a hybrid-polarimetric quad-pol SAR may be transformed into the conventional linearly polarized scattering matrix, thus preserving compatibility with the rich heritage of analysis tools developed for such radars.

A model for linearly polarized fully polarimetric backscatter measurements is used, incorporating the effects of system noise, channel amplitude, phase imbalance, crosstalk, and Faraday rotation. A step-by-step procedure is outlined for correction (or calibration) of fully polarimetric data subject to Faraday rotation, to recover the true scattering matrix. The procedure identifies steps for crosstalk removal and correction of channel imbalances that are robust in the presence of Faraday rotation. The final steps in the procedure involve a novel strategy for estimation and correction of Faraday rotation. Three approaches to estimate the (one-way) Faraday rotation angle /spl Omega/ directly from linear (quad-) polarized synthetic aperture radar (SAR) backscatter data obtained by a spaceborne SAR system are described. Each approach can initially be applied to the signature of any scatterer within the scene. Sensitivity analyses are presented that show that at least one of the measures can be used to estimate /spl Omega/ to within /spl plusmn/3/spl deg/ to 5/spl deg/, with reasonable levels of residual crosstalk, noise floor, channel amplitude, and phase imbalance. Ambiguities may be present in the estimates of /spl Omega/ of /spl plusmn/n/spl pi//2 - the impact of this is discussed, and several approaches are suggested to deal with this possibility. The approach described in this paper is relevant for future L-band spaceborne SARs and removes one key obstacle to the deployment of even longer wavelength SARs (e.g., an ultrahigh frequency or P-band SAR) in Earth orbit.

The potentially measurable effects of Faraday rotation on linearly polarized backscatter measurements from space are addressed. Single-polarized, dual-polarized, and quad-polarized backscatter measurements subject to Faraday rotation are first modeled. Then, the impacts are assessed using L-band polarimetric synthetic aperture radar (SAR) data. Due to Faraday rotation, the received signal will include other polarization characteristics of the surface, which may be detectable under certain conditions. Model results are used to suggest data characteristics that will reveal the presence of Faraday rotation in a given single-polarized, dual-polarized, or quad-polarized L-band SAR dataset, provided the user can identify scatterers within the scene whose general behavior is known or can compare the data to another, similar dataset with zero Faraday rotation. The data characteristics found to be most sensitive to a small amount of Faraday rotation (i.e., a one-way rotation

The paper explores the relationship between customer dissatisfaction/satisfaction and complaining responses among bank customers in Ghana banking industry. The study was a cross-sectional survey that used a self-administered structured questionnaire to collect primary data from 448 customers from ten selected banks in Ghana. The findings are that, though dissatisfaction causes customer complaining, dissatisfaction was more prevalent among non-complainers than complainers. Again, frequency of complaining is more likely to increase overall satisfaction if managed effectively. The most likely to be used complaining responses are complaining in person and refraining from using the bank’s services, while the least likely to be used complaining responses are complaining to the mass media and consumer associations. Moreover, public bank customers are more likely to complain by refraining from using the bank’s services and warning family and friends than private bank customers do. There was significant correlation between complaining responses and frequency of complaining, and between complaining responses and overall satisfaction. Theoretical and managerial implications are discussed. In spite of its limitations, the paper contributes to the body of knowledge in the area of consumer complaining behaviour in banking industry in emerging economies.

The paper proposes a model that helps to explain consumer behaviour towards Mobile Number Portability (MNP) policy and the influence of MNP adoption factors on consumer switching intention process in the telecommunication industry. The proposed model was tested using data from a cross-section of 736 subscribers of six global companies in Ghana’s mobile telecommunication industry, where MNP has been introduced. The findings indicate that MNP adoption can positively influence consumer switching. The effects of MNP adoption on switching intention is realised through three main channels; directly through MNP-induced self-efficacy (or switching efficacy) and indirectly through perceived switching costs and attitude towards switching. The proposed model helps explain about 50% of switching intention. The paper discusses implications of the findings to marketing theory and practice and provides directions for future research. The paper advances our knowledge in the impact of government/industrial policy on consumer behaviour in marketing.

In preparation for the Shuttle Imaging Radar-C/XSAR (SIR-C/XSAR) flights, the University of Michigan has been involved in the development of calibration procedures and precision calibration devices to quantify the complex radar images with an accuracy of 0.5 dB in magnitude and 5 degrees in phase. In this paper, the preliminary results of the SIR-C calibration and a summary of the University of Michigan's activity in the Raco calibration super-site is presented. In this calibration campaign an array of point calibration targets including trihedral corner reflectors and polarimetric active radar calibrators (PARCs) in addition to a uniform distributed target were used for characterizing the radiometric calibration constant and the distortion parameters of the C-band SAR. Two different calibration methods, one based on the application of point targets and the other based on the application of the distributed target, are used to calibrate the SIR-C data and the results are compared with calibrated images provided by JPL. The distributed target used in this experiment was a field of grass, sometimes covered with snow, whose differential Mueller matrix was measured immediately after the SIR-C overpass using The University of Michigan polarimetric scatterometer systems. The scatterometers were calibrated against a precision metallic sphere and measured 100 independent spatial samples for characterizing the differential Mueller matrix of the distributed target to achieve the desired calibration accuracy. The L-band SAR has not yet been adequately calibrated for inclusion here. >

Pharmaceutical regulatory bodies require minimal presence of solvent in an active pharmaceutical ingredient (API) after crystallization. From a processing point of view bigger crystals with minimal agglomeration and uniform size distribution are preferred to avoid solvent inclusion and for improved downstream processing. The current work addresses these issues encountered during the production of the potential anti-arrhythmic cardiovascular drug, AZD7009. This paper demonstrates that by applying the automated direct nucleation control (ADNC) approach problems with agglomeration and solvent inclusion were resolved. This model free approach automatically induces temperature cycles in the system, with the number of cycles, temperature range and adaptive heating and cooling rates determined to maintain the number of particles in the system, as measured by a focused beam reflectance measurement (FBRM) probe, within a constant range during the crystallization. The ADNC approach was able to produce larger and more uniform crystals and also removed the residual solvent trapped between the crystals compared to the typical crystallization operation using linear cooling profile. The results illustrate the application of process analytical technologies, such as FBRM and ATR-UV–vis spectroscopy, for the design of optimal crystallization operating conditions for the production of pharmaceuticals, and demonstrate that the ADNC approach can be used for rapid crystallization development for APIs exhibiting problems with agglomeration and solvent inclusion.

We have seen in the above that the SweepSAR technique offers the potential for significant reductions in the transmit peak and average power required for a SAR system. This is achieved by making full use of the areal extent of a reflector antenna on receive. The SweepSAR rate is not as big a problem as it might appear initially: note that in the 30 years since Seasat launched downlink rates for LEO satellites have increased significantly — from ∼85Mbps up to ∼640 Mbps. In addition, analog-todigital converters (ADCs) have increased in bandwidth from ∼ 20 MHz to several GHz.

In a previous paper, we have investigated the potential of the compact polarimetry mode at longer wavelengths in a space environment for soil moisture estimation. At longer wavelengths, one of the main challenges in dealing with compact polarimetry is the Faraday rotation estimation and correction. One proposed technique relies on bare surface scattering properties. Identifying the bare surfaces can be done using the conformity coefficient. This new coefficient can also be used to discriminate between surface, volume and double bounce scattering. It provides similar results to the Freeman-Durden classification in discriminating bare surfaces.

The interferometric radar (InSAR) design has undergone several iterations in the years that this mission has been under consideration. In the most recent proposal the InSAR is combined with a Lidar and the mission is called Deformation, Ecosystem Structure, and Dynamics of Ice (DESDynI). This spacecraft would be in a near-polar orbit around the Earth and repeatedly collect data to monitor changes in the solid Earth, vegetation, and ice. The radar is a repeat pass interferometric SAR with dual and quad polarization capability. This paper examines the state of the configuration of the radar including a “SweepSAR” method that has been incorporated as the present baseline.

Background and Objectives: Epidural catheters are seldom difficult to remove from patients. In fact, a review of the literature demonstrates only a few cases pertaining to epidurals and the unusual complication of catheter entrapment. Methods: This case report involves an uncomplicated obstetric patient who had an epidural placed for labor and in whom multiple attempts were needed to remove the catheter.

Recent updates to a geographical information system (GIS) called VICAR (Video Image Communication and Retrieval)/IBIS are described. The system is designed to handle data from many different formats (vector, raster, tabular) and many different sources (models, radar images, ground truth surveys, optical images). All the data are referenced to a single georeference plane, and average or typical values for parameters defined within a polygonal region are stored in a tabular file, called an info file. The info file format allows tracking of data in time, maintenance of links between component data sets and the georeference image, conversion of pixel values to `actual' values (e.g., radar cross-section, luminance, temperature), graph plotting, data manipulation, generation of training vectors for classification algorithms, and comparison between actual measurements and model predictions (with ground truth data as input).

[1] Radar penetration of mantling layers, and scattering from buried objects or interfaces, is a topic of current interest in both terrestrial and planetary remote sensing. We examine the behavior of surface and subsurface scattering interfaces and the types of information that may be obtained from observations in different polarizations and wavelengths. These results are applied to the design of a future Mars orbital synthetic aperture radar (SAR), for which we draw the following conclusions. (1) Mapping of buried geologic features is best accomplished using VV polarization, at an optimal wavelength determined by the competing effects of antenna gain, attenuation in the dust, and the reduction in effective surface roughness with wavelength. P band frequencies (∼1 GHz or less) offer the best opportunity for detection of moderately rough, buried features. (2) The relative roles of surface and subsurface scattering may be determined using measurements in HH and VV polarization, with a channel gain calibration better than 0.5 dB. (3) The thickness of a mantling layer (or ice mass) cannot be directly inferred from multiwavelength observations. Layer thickness may be inferred from the interferometric correlation of backscatter measurements collected on suitably spaced orbital passes, though the required phase measurement accuracy is challenging. While additional information may be gained by collecting scattering data in more polarizations or wavelengths, we suggest that the primary science goals of a Mars-orbiting radar could be accomplished by a single-wavelength system capable of collecting VV and HH polarizations with the calibration and orbit control needed to permit interferometric analysis.

MacSigma0 is an interactive tool for the Macintosh personnal computer which allows the user to display and make computations from radar data collected by the following sensors: JPL AIRSAR, ERS-1, JERS-1, and Magellan. MacSigma0 provides four basic functions: synthesis of images, statistical analysis of selected areas, analysis of corner reflectors as a calibration measure, and informative mouse tracking. Images, statistics, and calibration measures can be printed or saved in standard formats compatible with other applications for further analysis or for generation of presentation materials. >

NASA's Jet Propulsion Laboratory has produced an educational package entitled 'The SIR-C Education Program' (SIR-CED), designed as a two- to three-week module for Middle School and High School students. SIR-C stands for Spaceborne Imaging Radar-C and is the acronym used for a radar instrument flown on the Space Shuttle Endeavour in April of 1994 and scheduled for second flight in August. This paper gives a brief introduction to the SIR-CED program. The SIR-CED package consists of: a Teachers' Resource Guide (180 pages); presentation materials; lesson guides, including activities for students; a CD-ROM containing radar images, shuttle hand-held photographs taken by the astronauts, digitized location and topographic maps, ground photos, easy-to-use software for image display and analysis on Macintosh, SUN, and IBM PC computers; documentation; a selection of videos about imaging radar; and teacher workshops for training. The Teachers' Resource Guide contains a basic introduction to NASA's Mission to Planet Earth, how imaging radar and SIR-C fit into that program and how they work, and how scientists use imaging radar data in their studies of the Earth's environment. Also included in the package are easy-to-use software to display the images provided. The comprehensive data set incorporated into the SIR-CED CD-ROM may also be useful for some engineers and scientists, who wish to explore the potential of radar observation. >

The effect of Faraday rotation on spaceborne polarimetric SAR measurements is addressed. Single-polarized, dual- polarized and quad-polarized backscatter measurements subject to Faraday rotation are modeled. It is shown that due to Faraday rotation, the received signal includes other polarization characteristics of the surface. Techniques are developed to detect the presence of Faraday rotation in dual-polarized and quad-polarized SAR data. Finally, a novel approach for the correction (or calibration) of linearly polarized fully polarimetric data for Faraday rotation, to recover the `true' scattering matrix, is presented.

Modified VICARIIBIS GIS: Implementation and ApplicationLynne Norikane, Anthony Freeman, and Rob Casey*Jet Propulsion LaboratoryCalifornia Institute of Technology4800 Oak Grove DrivePasadena, California 91109*university of WashingtonDepartment of Electrical EngineeringSeattle, Washington 98105ABSTRACTThe analysis of multi-format, multi-parameter, and multi-temporal data sets can be very difficult. A system to effectivelyhandle data from different formats (vector, raster, tabular) and different sources (models, radar images, ground truth surveys,optical images) is being developed and tested as an extension to the VICAR/IBIS Geographical Information System (GIS)developed at the Jet Propulsion Laboratory. In its original implementation, all data is referenced to a single georeference plane inthe VICAR/IBIS GIS. Average or typical values for a parameter defined within a polygonal region are stored in unlabeledcolumns of a tabular file. We have replaced the tabular file format with an "info" file format. The info file format allows trackingof data in time, maintenance of links between component data sets and the georeference image, conversion of pixel values to"actual" values (e.g. radar cross-section, luminance, temperature), graph plotting, data manipulation, generation of training vectorsfor classification algorithms, and comparison between actual measurements and model predictions (with ground truth data asinput). We have successfully tested the GIS using multi-temporal, multi-sensor data sets from Flevoland in The Netherlands andBonanza Creek, in Alaska as part of a research study of applications of the GIS to remote sensing data under NASA's AppliedInformation Systems Program. Results will be presented at the conference.

Provides a response to the corrections submitted (vol. 46, no. 4, p. 1278, Apr 08) to the original article.

The synthetic aperture radar (SAR) is an imaging system that achieves high azimuthal resolution by tracking individual point scatterers using their phase histories, with the expected phase history of a particular point scatterer being derived from the assumed motion of the airborne SAR platform. Normally, it is assumed that the platform travels along a straight line path and that the radar pulses are emitted at equal spatial intervals. However, the aircraft carrying the SAR will be susceptible to extraneous across tracl motions and errors in the pulse spacing also may occur. These errors manifest themselves. as two forms of image degradation in the final image. Firstly, the image will be defocused due to an error in the expected quadratic phase history, and secondly, the image will contain geometric distortions due to an error in the linear phase history. An autofocus technique can be used to focus the image and produce a measure of the quadratic phase error that in turn can be used to estimate the geometric distortions that will be present in the final image. These distortions can be independently measured by direct comparison with a map of the imaged area. This paper describes the application of these methods to some real SAR data and discusses the results of the comparison of the measurements of autofocus and geometric distortions in terms of both the likely platform motions present and the viability of predicting geometric distortion using the autofocus measurements.

Uncorrected across-track motions of a synthetic aperture radar (SAR) platform can cause both a severe loss of azimuthal positioning accuracy in, and defocusing of, the resultant SAR image. It is shown how the results of an autofocus procedure can be incorporated in the azimuth processing to produce a fully focused image that is geometrically accurate in azimuth. Range positioning accuracy is also discussed, leading to a comprehensive treatment of all aspects of geometric accuracy. The system considered is an X-band SAR. >

Background Initial reports have described the poor outcome of unexpected cardiac arrest (CA) in intensive care unit (ICU) among COVID-19 patients in China and the USA. However, there are scarce data on characteristics and outcomes of such CA patients in Europe. Methods Prospective registry in 35 French ICUs, including all in-ICU CA in COVID-19 adult patients with cardiopulmonary resuscitation (CPR) attempt. Favorable outcome was defined as modified Rankin scale ranging from 0 to 3 at day 90 after CA. Results Among the 2425 COVID-19 patients admitted to ICU from March to June 2020, 186 (8%) experienced in-ICU CA, of whom 146/186 (78%) received CPR. Among these 146 patients, 117 (80%) had sustained return of spontaneous circulation, 102 (70%) died in the ICU, including 48 dying within the first day after CA occurrence and 21 after withdrawal of life-sustaining therapy. Most of CA were non-shockable rhythm (90%). At CA occurrence, 132 patients (90%) were mechanically ventilated, 83 (57%) received vasopressors and 75 (51%) had almost three organ failures. Thirty patients (21%) had a favorable outcome. Sepsis-related organ failure assessment score > 9 before CA occurrence was the single parameter constantly associated with unfavorable outcome in multivariate analysis. Conclusions In-ICU CA incidence remains high among a large multicenter cohort of French critically ill adults with COVID-19. However, 21% of patients with CPR attempt remained alive at 3 months with good functional status. This contrasts with other recent reports showing poor outcome in such patients. Trial registration: This study was retrospectively registered in ClinicalTrials.gov (NTC04373759) in April 2020 (https://www.clinicaltrials.gov/ct2/show/NCT04373759?term=acicovid&draw=2&rank=1).