1,503 research outputs found

    NASA Patent Abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 21) Abstracts

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    Abstracts are cited for 87 patents and applications introduced into the NASA scientific and technical information system during the period of January 1982 through June 1982. Each entry consists of a citation, an abstract, and in mose cases, a key illustration selected from the patent or patent application

    Material extrusion-based additive manufacturing: G-code and firmware attacks and Defense frameworks

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    Additive Manufacturing (AM) refers to a group of manufacturing processes that create physical objects by sequentially depositing thin layers. AM enables highly customized production with minimal material wastage, rapid and inexpensive prototyping, and the production of complex assemblies as single parts in smaller production facilities. These features make AM an essential component of Industry 4.0 or Smart Manufacturing. It is now used to print functional components for aircraft, rocket engines, automobiles, medical implants, and more. However, the increased popularity of AM also raises concerns about cybersecurity. Researchers have demonstrated strength degradation attacks on printed objects by injecting cavities in the design file which cause premature failure and catastrophic consequences such as failure of the attacked propeller of a drone during flight. Since a 3D printer is a cyber-physical system that connects the cyber and physical domains in a single process chain, it has a different set of vulnerabilities and security requirements compared to a conventional IT setup. My Ph.D. research focuses on the cybersecurity of one of the most popular AM processes, Material Extrusion or Fused Filament Fabrication (FFF). Although previous research has investigated attacks on printed objects by altering the design, these attacks often leave a larger footprint and are easier to detect. To address this limitation, I have focused on attacks at the intermediate stage of slicing through minimal manipulations at the individual sub-process level. By doing so, I have demonstrated that it is possible to implant subtle defects in printed parts that can evade detection schemes and bypass many quality assessment checks. In addition to exploring attacks through design files or network layer manipulations, I have also proposed firmware attacks that cause damage to the printed parts, the printer, and the printing facility. To detect sabotage attacks on FFF process, I have developed an attack detection framework that analyzes the cyber and physical domain state of the printing process and detects anomalies using a series of estimation and comparison algorithms in time, space, and frequency domains. An implementation case study confirms that cyber-physical security frameworks are an effective solution against sophisticated sabotage attacks. The increasing use of 3D printing technology to produce functional components underscores the growing importance of compliance and regulations in ensuring their quality and safety. Currently, there are no standards or best practices to guide a user in making a critical printing setup forensically ready. Therefore, I am proposing a novel forensic readiness framework for material extrusion-based 3D printing that will guide standards organizations in formulating compliance criteria for important 3D printing setups. I am optimistic that my offensive and defensive research endeavors presented in this thesis will serve as a valuable resource for researchers and industry practitioners in creating a safer and more secure future for additive manufacturing

    The South African Astronomical Observatory

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    Topics discussed in the Overview of Year 1988 include the following: Supernova in the Large Magellanic Cloud; Galaxies; Ground based observations of celestial x ray sources; the Magellanic Clouds; Pulsating variables; Galactic structure; Binary star phenomena; The provision of photometric standards; Nebulae and interstellar matter; Stellar astrophysics; Astrometry; Solar system studies; Visitors programs; Publications; and General matters

    NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 36)

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    Abstracts are provided for 63 patents and patent applications entered into the NASA scientific and technical information systems during the period July 1989 through December 1989. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

    NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 25)

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    Abstracts are provided for 102 patents and patent applications entered into the NASA scientific and technical information system during the period January 1984 through June 1984. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

    Spartan Daily, February 3, 1976

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    Volume 66, Issue 4https://scholarworks.sjsu.edu/spartandaily/6035/thumbnail.jp

    Computational Resource Abuse in Web Applications

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    Internet browsers include Application Programming Interfaces (APIs) to support Web applications that require complex functionality, e.g., to let end users watch videos, make phone calls, and play video games. Meanwhile, many Web applications employ the browser APIs to rely on the user's hardware to execute intensive computation, access the Graphics Processing Unit (GPU), use persistent storage, and establish network connections. However, providing access to the system's computational resources, i.e., processing, storage, and networking, through the browser creates an opportunity for attackers to abuse resources. Principally, the problem occurs when an attacker compromises a Web site and includes malicious code to abuse its visitor's computational resources. For example, an attacker can abuse the user's system networking capabilities to perform a Denial of Service (DoS) attack against third parties. What is more, computational resource abuse has not received widespread attention from the Web security community because most of the current specifications are focused on content and session properties such as isolation, confidentiality, and integrity. Our primary goal is to study computational resource abuse and to advance the state of the art by providing a general attacker model, multiple case studies, a thorough analysis of available security mechanisms, and a new detection mechanism. To this end, we implemented and evaluated three scenarios where attackers use multiple browser APIs to abuse networking, local storage, and computation. Further, depending on the scenario, an attacker can use browsers to perform Denial of Service against third-party Web sites, create a network of browsers to store and distribute arbitrary data, or use browsers to establish anonymous connections similarly to The Onion Router (Tor). Our analysis also includes a real-life resource abuse case found in the wild, i.e., CryptoJacking, where thousands of Web sites forced their visitors to perform crypto-currency mining without their consent. In the general case, attacks presented in this thesis share the attacker model and two key characteristics: 1) the browser's end user remains oblivious to the attack, and 2) an attacker has to invest little resources in comparison to the resources he obtains. In addition to the attack's analysis, we present how existing, and upcoming, security enforcement mechanisms from Web security can hinder an attacker and their drawbacks. Moreover, we propose a novel detection approach based on browser API usage patterns. Finally, we evaluate the accuracy of our detection model, after training it with the real-life crypto-mining scenario, through a large scale analysis of the most popular Web sites

    NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 35)

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    Abstracts are provided for 58 patents and patent applications entered into the NASA scientific and technical information systems during the period January 1989 through June 1989. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

    NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 38)

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    Abstracts are provided for 132 patents and patent applications entered into the NASA scientific and technical information system during the period July 1990 through December 1990. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application
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