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This paper summarizes over 60 years of radar system development at MIT Lincoln Laboratory, from early research on satellite tracking and planetary radar to the present ability to perform the centimeter-resolution imaging of resident space objects and future plans to extend this capability to geosynchronous range. [ABSTRACT FROM AUTHOR]

There is growing demand for the high-fidelity characterization of satellites in Geosynchronous Earth Orbit (GEO) to support Space Domain Awareness (SDA). This is particularly true for newly launched satellites, where it is necessary for satellite providers to ascertain whether components have deployed properly. Conventional wideband radar systems are capable of imaging satellites provided that (i) they have sufficient power aperture and bandwidth, and (ii) they observe enough target aspect change to generate a resolved image. While wideband radars are used routinely for characterizing satellites in Low-Earth Orbit (LEO), powerful radars with sensitivity sufficient for large GEO ranges (36,000 km or greater) are lacking. Thus, researchers often rely on more widely available high-power narrowband tracking radars for GEO characterization. In this paper, we present a novel range-Doppler-time (RDT) tensor processing technique for GEO characterization with narrowband radar. This technique encapsulates the strengths of previously proposed methods for narrowband-radar characterization at GEO, providing a generalized approach that can be applied in a variety of settings. The technique generates fully resolved 2D images of rotating GEO satellites in low-bandwidth scenarios. In cases where aspect change is limited, the technique provides detailed Doppler information for enhanced satellite status monitoring. This work presents a comprehensive quantitative analysis of the technique that considers the impact of key parameters on characterization performance. Simulated radar data, and radar data collected in a compact range on a scaled satellite model, are used to evaluate the technique. [ABSTRACT FROM AUTHOR]

Today, studying continuous clinical decision support system (CDSS) use is critical as continuity is a prerequisite to sustaining successful CDSS implementations. Previous health information technology (HIT) research has focused on HIT acceptance via information system-related constructs. Theoretical models explaining HIT use are limited and obfuscated other phases of HIT, such as continuous use in a clinical context. This study seeks to fill this gap by integrating context-related factors with IS factors in a theoretical framework that explains the antecedents of continuous use. To validate this model, data were collected from physicians after six months of using CDSS as well as system usage data from system logs. Threats to physician professional identity surpassed the intention to continue using CDSS, influencing its use by physicians in the first six months, and patients affected by the system influenced physician satisfaction with the system and, hence, their use of the system. This study reveals physicians' continuous use of CDSS and explains the effects of healthcare contexts on physicians' behaviour. [ABSTRACT FROM AUTHOR]

Healthcare is an area that has benefitted from the developments in wearable device technology. Seniors, who usually suffer from multiple comorbidities, are among the target users of these devices, and research has shown potential health benefits for seniors when they use these devices effectively. However, the adoption rate of wearable devices is low, especially among seniors, preventing the full utilisation of their data in healthcare. In this study, we interviewed forty-four seniors across North America and collected data from their wearable devices to develop a theoretical affordance network-based model to explain seniors' effective use of wearable devices. Our model indicates that despite the apparent simplicity of wearable devices, they have multiple affordances that help seniors achieve several goals, including activity monitoring, activity planning, and activity improvement. Furthermore, we identified factors that enable seniors to actualise the affordances of wearable devices and achieve their goals. The results of this study suggest a strong relationship between seniors' mental and physical capabilities and their willingness to use and benefit from wearable devices. We join other researchers in their call for a contextual study on consumer technology use. [ABSTRACT FROM AUTHOR]

What was already known on the topic: • Social media has been used by care-providers and patients to improve patient care. • There have been several failed attempts to use social media and online activity for epidemic surveillance. • Current surveillance systems have limitations that hinder their effectiveness. What this study added to our knowledge: • Twitter can be used to support, not replace, traditional surveillance systems. • Digital divide and information accuracy are two top factors impacting the efficacy of social media in epidemic surveillance. The risk of global epidemic outbreaks led to the development of epidemic tracking services dedicated to track and warn against them. Despite the usefulness of these services, they suffer from shortcomings that impact their efficiency. This study examines the efficacy of social media in epidemic outbreak surveillance by studying Twitter users' behavior related to the Zika virus outbreak in 2015–2016 and how this behavior can be used to track and predict Zika virus. We collected 67,000 tweets in English and Spanish under the hashtag #Zikavirus and #Zika in the period from October 1st, 2015 to February 25th, 2016. We examined the tweets using text analytics techniques and extracted the important concepts. We analyzed the differences in using these concepts from one month to another. There are significant differences between the numbers of tweets during the Zika outbreak as well as between the concepts used in English and Spanish tweets. The differences in Zika epidemic related tweets evolved with the epidemic outbreak and reflected the different stages of the epidemic. However, those differences also reflected a digital divide between developed and developing communities. The number of tweets was related to the threatened community rather than the severity of the threat. While Twitter can be used to augment current epidemic tracking systems, it cannot replace them. We identified digital divide and threat of misleading information as two factors that limit the dependence on Twitter as an epidemic tracking system. [ABSTRACT FROM AUTHOR]

• Using a qualitative methodology to explore seniors' use of wearable devices. • Seniors have a multitude of social contexts that influence their decision to use wearable devices. • Level and style of exercising influence seniors' decision to use wearable devices. • The impact of wearable devices on users depends on their prior level of exercising. Wearable devices have potential benefits for seniors healthcare. However, the rate of adoption of these devices is very low for seniors compared to other age groups. This study aims at examining the factors that influence seniors' use of wearable devices and the effect of these devices on seniors' behavior. This study uses qualitative methods to address the research questions. We conducted 26 interviews of seniors who have never used wearable devices before. We interviewed seniors before and after using activity tracking wearable devices. Furthermore, we collected wearable device quantitative data to support interview results. Seniors adoption of wearable devices involve several factors that can be categorized as technology related factors such as the complexity and customizability of wearable devices and individual related factors such as social influence, self-efficacy. Furthermore, the effects of using wearable devices vary among seniors depending on their activity patterns and exercise schedule. seniors' use of wearable devices is a complex process that involves the interactions of social, psychological, and technological factors. By understanding these factors, we can develop strategies to enhance seniors' use of wearable devices and improve their overall health and quality of life. [ABSTRACT FROM AUTHOR]

Background: Computerized clinical decision support systems (CDSSs) have emerged as an approach to improve compliance of clinicians with clinical practice guidelines (CPGs). Research utilizing CDSS has primarily been conducted in clinical contexts with clear diagnostic criteria such as diabetes and cardiovascular diseases. In contrast, research on CDSS for pain management and more specifically neuropathic pain has been limited. A CDSS for neuropathic pain has the potential to enhance patient care as the challenge of diagnosing and treating neuropathic pain often leads to tension in clinician-patient relationships. Objective: The aim of this study was to design and evaluate a CDSS aimed at improving the adherence of interprofessional primary care clinicians to CPG for managing neuropathic pain. Methods: Recommendations from the Canadian CPGs informed the decision pathways. The development of the CDSS format and function involved participation of multiple stakeholders and end users in needs assessment and usability testing. Clinicians, including family medicine physicians, residents, and nurse practitioners, in three academic teaching clinics were trained in the use of the CDSS. Evaluation over one year included the measurement of utilization of the CDSS; change in reported awareness, agreement, and adoption of CPG recommendations; and change in the observed adherence to CPG recommendations. Results: The usability testing of the CDSS was highly successful in the prototype environment. Deployment in the clinical setting was partially complete by the time of the study, with some limitations in the planned functionality. The study population had a high level of awareness, agreement, and adoption of guideline recommendations before implementation of CDSS. Nevertheless, there was a small and statistically significant improvement in the mean awareness and adoption scores over the year of observation (P =.01 for mean awareness scores at 6 and 12 months compared with baseline, for mean adoption scores at 6 months compared with baseline, and for mean adoption scores at 12 months). Documenting significant findings related to diagnosis of neuropathic pain increased significantly. Clinicians accessed CPG information more frequently than they utilized data entry functions. Nurse practitioners and first year family medicine trainees had higher utilization than physicians. Conclusions: We observed a small increase in the adherence to CPG recommendations for managing neuropathic pain. Clinicians utilized the CDSS more as a source of knowledge and as a training tool than as an ongoing dynamic decision support. [ABSTRACT FROM AUTHOR]

Reviews previous presentation of an approach to a four-way hybrid ring power divider design. Way to reduce a multiport matching problem to a one-port matching problem; Optimization of the star-ring geometry; Analysis of the matched and mismatched five-port ring geometry in terms of the couplings and phase differences between the adjacent ports.