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EROS (microkernel)
Extremely Reliable Operating System (EROS) is an operating system developed starting in 1991 at the University of Pennsylvania, and then Johns Hopkins University, and The EROS Group, LLC. Features include automatic data and process persistence, some preliminary real-time support, and capability-based security. EROS is purely a research operating system, and was never deployed in real world use. , development stopped in favor of a successor system, CapROS. Key concepts The overriding goal of the EROS system (and its relatives) is to provide strong support at the operating system level for the efficient restructuring of critical applications into small communicating components. Each component can communicate with the others only through protected interfaces, and is isolated from the rest of the system. A ''protected interface'', in this context, is one that is enforced by the lowest level part of the operating system, the kernel. That is the only part of the system that can move inf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Pennsylvania
The University of Pennsylvania (also known as Penn or UPenn) is a private research university in Philadelphia. It is the fourth-oldest institution of higher education in the United States and is ranked among the highest-regarded universities by numerous organizations and scholars. While the university dates its founding to 1740, it was created by Benjamin Franklin and other Philadelphia citizens in 1749. It is a member of the Ivy League. The university has four undergraduate schools as well as twelve graduate and professional schools. Schools enrolling undergraduates include the College of Arts and Sciences, the School of Engineering and Applied Science, the Wharton School, and the School of Nursing. Among its highly ranked graduate schools are its law school, whose first professor wrote the first draft of the United States Constitution, its medical school, the first in North America, and Wharton, the first collegiate business school. Penn's endowment is US$20.7 billio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inter-process Communication
In computer science, inter-process communication or interprocess communication (IPC) refers specifically to the mechanisms an operating system provides to allow the processes to manage shared data. Typically, applications can use IPC, categorized as clients and servers, where the client requests data and the server responds to client requests. Many applications are both clients and servers, as commonly seen in distributed computing. IPC is very important to the design process for microkernels and nanokernels, which reduce the number of functionalities provided by the kernel. Those functionalities are then obtained by communicating with servers via IPC, leading to a large increase in communication when compared to a regular monolithic kernel. IPC interfaces generally encompass variable analytic framework structures. These processes ensure compatibility between the multi-vector protocols upon which IPC models rely. An IPC mechanism is either synchronous or asynchronous. Synchr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNOSIS
Gnosis is the common Greek noun for knowledge ( γνῶσις, ''gnōsis'', f.). The term was used among various Hellenistic religions and philosophies in the Greco-Roman world. It is best known for its implication within Gnosticism, where it signifies a spiritual knowledge or insight into humanity's real nature as divine, leading to the deliverance of the divine spark within humanity from the constraints of earthly existence. Etymology ''Gnosis'' is a feminine Greek noun which means "knowledge" or "awareness." Liddell Scottbr>entryγνῶσις, εως, ἡ, A. seeking to know, inquiry, investigation, esp. judicial, "τὰς τῶν δικαστηρίων γ." D.18.224; "τὴν κατὰ τοῦ διαιτητοῦ γdeetr." Id.21.92, cf. 7.9, Lycurg.141; "γ. περὶ τῆς δίκης" PHib.1.92.13 (iii B. C.). 2. result of investigation, decision, PPetr.3p.118 (iii B. C.). II. knowing, knowledge, Heraclit.56; opp. ἀγνωσίη, Hp. Vict.1.23 (dub.); opp. ἄγνο ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jochen Liedtke
Jochen Liedtke (26 May 1953 – 10 June 2001) was a German computer scientist, noted for his work on microkernel operating systems, especially in creating the L4 microkernel family. Vita Education In the mid-1970s Liedtke studied for a diploma degree in mathematics at the Bielefeld University. His thesis project was to build a compiler for the programming language ELAN, which had been launched for teaching programming in German schools. The compiler was written in ELAN. Post grad After his graduation in 1977, he remained at Bielefeld and worked on an Elan environment for the Zilog Z80 microprocessor. This required a runtime system (environment), which he named Eumel ("Extendable Multiuser Microprocessor ELAN-System", but also a colloquial north-German term for likeable fool. Eumel grew into a complete multi-tasking, multi-user operating system supporting orthogonal persistence, which started shipping (by whom? to whom?) in 1980 and was later ported to Zilog Z8000, Motoro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L4 Microkernel Family
L4 is a family of second-generation microkernels, used to implement a variety of types of operating systems (OS), though mostly for Unix-like, ''Portable Operating System Interface'' (POSIX) compliant types. L4, like its predecessor microkernel L3, was created by German computer scientist Jochen Liedtke as a response to the poor performance of earlier microkernel-based OSes. Liedtke felt that a system designed from the start for high performance, rather than other goals, could produce a microkernel of practical use. His original implementation in hand-coded Intel i386-specific assembly language code in 1993 sparked intense interest in the computer industry. Since its introduction, L4 has been developed to be cross-platform and to improve security, isolation, and robustness. There have been various re-implementations of the original binary L4 kernel application binary interface (ABI) and its successors, including ''L4Ka::Pistachio'' (Karlsruhe Institute of Technology), ''L4/MIPS' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HRU (security)
The HRU security model (Michael A. Harrison, Harrison, Ruzzo, Jeffrey Ullman, Ullman model) is an operating system level computer security model which deals with the data integrity, integrity of access control, access rights in the system. It is an extension of the Graham-Denning model, based around the idea of a finite set of algorithm, procedures being available to edit the access rights of a subject s on an object o. It is named after its three authors, Michael A. Harrison, Walter L. Ruzzo and Jeffrey D. Ullman. Along with presenting the model, Harrison, Ruzzo and Ullman also discussed the possibilities and limitations of proving the safety of systems using an algorithm. Description of the model The HRU model defines a ''protection system'' consisting of a set of generic rights ''R'' and a set of commands ''C''. An instantaneous description of the system is called a ''configuration'' and is defined as a tuple (S,O,P) of current subjects S, current objects O and an access matri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipton
Lipton is a British brand of tea, owned by Ekaterra. Lipton was also a supermarket chain in the United Kingdom, later sold to Argyll Foods, after which the company sold only tea. The company is named after its founder, Sir Thomas Lipton, who founded it in 1890. The Lipton ready-to-drink beverages are sold by "Pepsi Lipton International", a company jointly owned by Ekaterra and PepsiCo. They also make soup, but this is not as widespread. History Origins In 1871, Thomas Lipton (1848–1931) of Glasgow, Scotland, used his small savings to open his own shop, and by the 1880s the business had grown to more than 200 shops. In 1929, the Lipton grocery retail business was one of the companies that merged with Home and Colonial Stores, Maypole Dairy Company, Vyes & Boroughs, Templetons, Galbraiths & Pearks to form a food group with more than 3,000 shops. The group traded in the high street under various names, but was registered on the UK stock market as Allied Suppliers. Lipton's bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM I
IBM i (the ''i'' standing for ''integrated'') is an operating system developed by IBM for IBM Power Systems. It was originally released in 1988 as OS/400, as the sole operating system of the IBM AS/400 line of systems. It was renamed to i5/OS in 2004, before being renamed a second time to IBM i in 2008. It is an evolution of the System/38 CPF operating system, with compatibility layers for System/36 SSP and AIX applications. It inherits a number of distinctive features from the System/38 platform, including the Machine Interface, the implementation of object-based addressing on top of a single-level store, and the tight integration of a relational database into the operating system. History Origin OS/400 was developed alongside the AS/400 hardware platform beginning in December 1985. Development began in the aftermath of the failure of the Fort Knox project, which left IBM without a competitive midrange system. During the Fort Knox project, a skunkworks project was started ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plessey System 250
Plessey System 250, also known as PP250, was the first operational computer to implement capability-based addressing, to check and balance the computation as a pure Church–Turing machine. Plessey built the systems for a British Army message routing project. Description A Church–Turing machine is a digital computer that encapsulates the symbols in a thread of computation as a chain of protected abstractions by enforcing the dynamic binding laws of Alonzo Church's lambda calculus Other capability based computers, which includCHERIand CAP computers, are hybrids. They retain default instructions that can access every word of accessible physical or logical (paged) memory. It is an unavoidable characteristic of the von Neumann architecture that is founded on shared random access memory and trust in the sharing default access rights. For example, every word in every page managed by the virtual memory manager in an operating system using a memory management unit (MMU) must be truste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DO-178B
DO-178B, Software Considerations in Airborne Systems and Equipment Certification is a guideline dealing with the safety of safety-critical software used in certain airborne systems. It was jointly developed by the safety-critical working group RTCA SC-167 of the Radio Technical Commission for Aeronautics (RTCA) and WG-12 of the European Organisation for Civil Aviation Equipment (EUROCAE). RTCA published the document as RTCA/DO-178B, while EUROCAE published the document as ED-12B. Although technically a guideline, it was a ''de facto'' standard for developing avionics software systems until it was replaced in 2012 by DO-178C. The Federal Aviation Administration (FAA) applies DO-178B as the document it uses for guidance to determine if the software will perform reliably in an airborne environment, when specified by the Technical Standard Order (TSO) for which certification is sought. In the United States, the introduction of TSOs into the airworthiness certification process, and b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Flight Control System
A conventional Fixed-wing aircraft, fixed-wing aircraft flight control system consists of flight control surfaces, the respective cockpit controls, connecting linkages, and the necessary operating mechanisms to control an aircraft's direction in flight. Aircraft engine controls are also considered as flight controls as they change speed. The fundamentals of aircraft controls are explained in flight dynamics (fixed-wing aircraft), flight dynamics. This article centers on the operating mechanisms of the flight controls. The basic system in use on aircraft first appeared in a readily recognizable form as early as April 1908, on Louis Blériot's Blériot VIII pioneer-era monoplane design. Cockpit controls Primary controls Generally, the primary cockpit flight controls are arranged as follows:Langewiesche, WolfgangStick and Rudder: An Explanation of the Art of Flying McGraw-Hill Professional, 1990, , . * a Yoke (aircraft), control yoke (also known as a control column), centre s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
