411 research outputs found

    The NASA SBIR product catalog

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    The purpose of this catalog is to assist small business firms in making the community aware of products emerging from their efforts in the Small Business Innovation Research (SBIR) program. It contains descriptions of some products that have advanced into Phase 3 and others that are identified as prospective products. Both lists of products in this catalog are based on information supplied by NASA SBIR contractors in responding to an invitation to be represented in this document. Generally, all products suggested by the small firms were included in order to meet the goals of information exchange for SBIR results. Of the 444 SBIR contractors NASA queried, 137 provided information on 219 products. The catalog presents the product information in the technology areas listed in the table of contents. Within each area, the products are listed in alphabetical order by product name and are given identifying numbers. Also included is an alphabetical listing of the companies that have products described. This listing cross-references the product list and provides information on the business activity of each firm. In addition, there are three indexes: one a list of firms by states, one that lists the products according to NASA Centers that managed the SBIR projects, and one that lists the products by the relevant Technical Topics utilized in NASA's annual program solicitation under which each SBIR project was selected

    NASA SBIR product catalog, 1991

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    This catalog is a partial list of products of NASA SBIR (Small Business Innovation Research) projects that have advanced to some degree into Phase 3. While most of the products evolved from work conducted during SBIR Phase 1 and 2, a few advanced to commercial status solely from Phase 1 activities. The catalog presents information provided to NASA by SBIR contractors who wished to have their products exhibited at Technology 2001, a NASA-sponsored technology transfer conference held in San Jose, California, on December 4, 5, and 6, 1991. The catalog presents the product information in the following technology areas: computer and communication systems; information processing and AI; robotics and automation; signal and image processing; microelectronics; electronic devices and equipment; microwave electronic devices; optical devices and lasers; advanced materials; materials processing; materials testing and NDE; materials instrumentation; aerodynamics and aircraft; fluid mechanics and measurement; heat transfer devices; refrigeration and cryogenics; energy conversion devices; oceanographic instruments; atmosphere monitoring devices; water management; life science instruments; and spacecraft electromechanical systems

    Epigenetic Profiling of Mammalian Retrotransposons

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    Over evolutionary time, mammalian genomes have accumulated a large number of retrotransposons, making up about half of the genome in any given species. These retrotransposons are typically repressed by epigenetic mechanisms, one of the main ones being DNA methylation. It is well known that improper DNA methylation of retrotransposons can have unwanted consequences on nearby gene expression, and hypomethylation of retrotransposons has been frequently observed in various cancers. Nevertheless, it has been notoriously difficult to study retrotransposon loci individually due to the highly repetitive nature of their sequences. To address this issue, we have developed a novel protocol termed HT-TREBS (High-Throughput Targeted Repeat Element Bisulfite Sequencing), which is designed to survey the DNA methylation levels of a large number of interspersed repeat elements on an individual-locus basis. Here we have used this technique on two mammalian retrotransposon families: IAP LTRs in mouse, and the AluYa5 and AluYb8 subfamilies of Alu elements in humans. According to the results, the majority of retrotransposons (~95%) are heavily methylated in mammalian somatic cells. Moreover, only a fraction of loci appear to be sensitive to cell state in both species. Approximately 25% IAP LTRs showed hypomethylation in mouse ES cells, and ~50% in mouse cancer (Neuro2A) cells. In humans, however, the level of response to tumorigenesis in the breast was much more constrained, with only 1% AluYb8 elements being expected to show hypomethylation at an early stage. Interestingly, our results also revealed extensive (up to 10-fold) inter-individual variation in the level of DNA methylation of AluYa5 and AluYb8 elements in humans, similar to the variation previously noted regarding IAP LTRs in mice. Overall, these results highlight the dynamic nature of DNA methylation at retrotransposons, which further leads us to speculate its unique contribution to mammalian evolution and disease susceptibility by allowing for epigenetic variation within one species. Furthermore, it also suggests the potential utility of some of these elements which are sensitive to cell state, but show less variability between individuals, to be used as epigenetic biomarkers for tracking disease progression

    Improving Android app security and privacy with developers

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    Existing research has uncovered many security vulnerabilities in Android applications (apps) caused by inexperienced, and unmotivated developers. Especially, the lack of tool support makes it hard for developers to avoid common security and privacy problems in Android apps. As a result, this leads to apps with security vulnerability that exposes end users to a multitude of attacks. This thesis presents a line of work that studies and supports Android developers in writing more secure code. We first studied to which extent tool support can help developers in creating more secure applications. To this end, we developed and evaluated an Android Studio extension that identifies common security problems of Android apps, and provides developers suggestions to more secure alternatives. Subsequently, we focused on the issue of outdated third-party libraries in apps which also is the root cause for a variety of security vulnerabilities. Therefore, we analyzed all popular 3rd party libraries in the Android ecosystem, and provided developers feedback and guidance in the form of tool support in their development environment to fix such security problems. In the second part of this thesis, we empirically studied and measured the impact of user reviews on app security and privacy evolution. Thus, we built a review classifier to identify security and privacy related reviews and performed regression analysis to measure their impact on the evolution of security and privacy in Android apps. Based on our results we proposed several suggestions to improve the security and privacy of Android apps by leveraging user feedbacks to create incentives for developers to improve their apps toward better versions.Die bisherige Forschung zeigt eine Vielzahl von Sicherheitslücken in Android-Applikationen auf, welche sich auf unerfahrene und unmotivierte Entwickler zurückführen lassen. Insbesondere ein Mangel an Unterstützung durch Tools erschwert es den Entwicklern, häufig auftretende Sicherheits- und Datenschutzprobleme in Android Apps zu vermeiden. Als Folge führt dies zu Apps mit Sicherheitsschwachstellen, die Benutzer einer Vielzahl von Angriffen aussetzen. Diese Dissertation präsentiert eine Reihe von Forschungsarbeiten, die Android-Entwickler bei der Entwicklung von sichereren Apps untersucht und unterstützt. In einem ersten Schritt untersuchten wir, inwieweit die Tool-Unterstützung Entwicklern beim Schreiben von sicherem Code helfen kann. Zu diesem Zweck entwickelten und evaluierten wir eine Android Studio-Erweiterung, die gängige Sicherheitsprobleme von Android-Apps identifiziert und Entwicklern Vorschläge für sicherere Alternativen bietet. Daran anknüpfend, konzentrierten wir uns auf das Problem veralteter Bibliotheken von Drittanbietern in Apps, die ebenfalls häufig die Ursache von Sicherheitslücken sein können. Hierzu analysierten wir alle gängigen 3rd-Party-Bibliotheken im Android-Ökosystem und gaben den Entwicklern Feedback und Anleitung in Form von Tool-Unterstützung in ihrer Entwicklungsumgebung, um solche Sicherheitsprobleme zu beheben. Im zweiten Teil dieser Dissertation untersuchten wir empirisch die Auswirkungen von Benutzer-Reviews im Android Appstore auf die Entwicklung der Sicherheit und des Datenschutzes von Apps. Zu diesem Zweck entwickelten wir einen Review-Klassifikator, welcher in der Lage ist sicherheits- und datenschutzbezogene Reviews zu identifizieren. Nachfolgend untersuchten wir den Einfluss solcher Reviews auf die Entwicklung der Sicherheit und des Datenschutzes in Android-Apps mithilfe einer Regressionsanalyse. Basierend auf unseren Ergebnissen präsentieren wir verschiedene Vorschläge zur Verbesserung der Sicherheit und des Datenschutzes von Android-Apps, welche die Reviews der Benutzer zur Schaffung von Anreizen für Entwickler nutzen

    QuiiQ automation foundation

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    Tese de mestrado. Engenharia Informática. Faculdade de Engenharia. Universidade do Porto. 200

    US and USSR Military Aircraft and Missile Aerodynamics 1970-1980. A selected, annotated bibliography, volume 1

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    The purpose of this selected bibliography (281 citations) is to list available, unclassified, unlimited publications which provide aerodynamic data on major aircraft and missiles currently used by the military forces of the United States of America and the Union of Soviet Socialist Republics. Technical disciplines surveyed include aerodynamic performance, static and dynamic stability, stall-spin, flutter, buffet, inlets nozzles, flap performance, and flying qualities. Concentration is on specific aircraft including fighters, bombers, helicopters, missiles, and some work on transports, which are or could be used for military purposes. The bibliography is limited to material published from 1970 to 1980. The publications herein illustrate many of the types of aerodynamic data obtained in the course of aircraft development programs and may therefore provide some guidance in identifying problems to be expected in the conduct of such work. As such, this information may be useful in planning future research programs
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