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Resource-oriented Computing
Resource-oriented computing (ROC) is a simple abstract computing model used for describing, designing, and implementing software and software systems. The fundamental idea behind ROC is derived from the World Wide Web, Unix, and other sources as well as original research conducted at HP Laboratories. Fundamental concepts Resource-oriented computing describes an abstract computing model. The fundamental idea is that sets of information known as resources are treated as abstracts; that is, a resource is a Platonic concept of the information that is the subject of a computation process. Resources are identified by logical addresses (typically a URI) and processing is defined using compositions and sequences of resource requests. At the physical level, a ROC system processes resource-representations, executes transformations and, in so doing, computes new resources. In this respect ROC is no different from any other computational model – computation is performed to collate and reve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World Wide Web
The World Wide Web (WWW or simply the Web) is an information system that enables Content (media), content sharing over the Internet through user-friendly ways meant to appeal to users beyond Information technology, IT specialists and hobbyists. It allows documents and other web resources to be accessed over the Internet according to specific rules of the HTTP, Hypertext Transfer Protocol (HTTP). The Web was invented by English computer scientist Tim Berners-Lee while at CERN in 1989 and opened to the public in 1993. It was conceived as a "universal linked information system". Documents and other media content are made available to the network through web servers and can be accessed by programs such as web browsers. Servers and resources on the World Wide Web are identified and located through character strings called uniform resource locators (URLs). The original and still very common document type is a web page formatted in Hypertext Markup Language (HTML). This markup lang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix
Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including University of California, Berkeley ( BSD), Microsoft (Xenix), Sun Microsystems ( SunOS/ Solaris), HP/ HPE ( HP-UX), and IBM ( AIX). The early versions of Unix—which are retrospectively referred to as " Research Unix"—ran on computers such as the PDP-11 and VAX; Unix was commonly used on minicomputers and mainframes from the 1970s onwards. It distinguished itself from its predecessors as the first portable operating system: almost the entire operating system is written in the C programming language (in 1973), which allows U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HP Laboratories
HP Labs is the exploratory and advanced research group for HP Inc. HP Labs' headquarters is in Palo Alto, California and the group has research and development facilities in Bristol, UK. The development of programmable desktop calculators, inkjet printing, and 3D graphics are credited to HP Labs researchers. HP Labs was established on March 3, 1966, by Hewlett-Packard founders Bill Hewlett and David Packard, seeking to create an organization not bound by day-to-day business concerns. The labs have downsized dramatically; in August 2007, HP executives drastically diminished the number of projects, down from 150 to 30. As of 2018, HP Labs has just over 200 researchers, compared to earlier staffing levels of 500 researchers. With Hewlett Packard Enterprise being spun off from Hewlett-Packard on November 1, 2015, and the remaining company being renamed to HP Inc., the research lab also spun off Hewlett Packard Labs to Hewlett Packard Enterprise and HP Labs was kept for HP Inc. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resource (computer Science)
In computing, a system resource, or simply resource, is any physical or virtual component of limited availability that is accessible to a computer. All connected devices and internal system components are resources. Virtual system resources include files (concretely file handles), network connections (concretely network sockets), and memory areas. Managing resources is referred to as resource management, and includes both preventing resource leaks (not releasing a resource when a process has finished using it) and dealing with resource contention (when multiple processes wish to access a limited resource). Computing resources are used in cloud computing to provide services through networks. Major resource types * Interrupt request (IRQ) lines * Direct memory access (DMA) channels * Port-mapped I/O * Memory-mapped I/O * Locks * External devices * External memory or objects, such as memory managed in native code, from Java; or objects in the Document Object Model ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Identity (object-oriented Programming)
In object-oriented programming, analysis and design, object identity is the fundamental property of every object that it is distinct from other objects. Objects have identity are distinct even when they are otherwise indistinguishable, i.e. equal. In this way, object identity is closely related to the philosophical meaning. Identity and references A reference can be used to refer to an object with a specific identity. A reference contains the information that is necessary for the identity property to be realized in the programming language, and allows access to the object with the identity. A type of a target of a reference is a role. Typically, references are isomorphic to memory addresses. However, multiple such references can refer to the same object, if some form of address mapping is present ( virtual addresses / page tables / memory segments). Object identity is less useful as a semantic concept in environments or situations in which the structure of objects is not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computation
A computation is any type of arithmetic or non-arithmetic calculation that is well-defined. Common examples of computation are mathematical equation solving and the execution of computer algorithms. Mechanical or electronic devices (or, historically, people) that perform computations are known as ''computers''. Computer science is an academic field that involves the study of computation. Introduction The notion that mathematical statements should be 'well-defined' had been argued by mathematicians since at least the 1600s, but agreement on a suitable definition proved elusive. A candidate definition was proposed independently by several mathematicians in the 1930s. The best-known variant was formalised by the mathematician Alan Turing, who defined a well-defined statement or calculation as any statement that could be expressed in terms of the initialisation parameters of a Turing machine. Other (mathematically equivalent) definitions include Alonzo Church's '' lambda-defin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reification (computer Science)
In computer science, reification is the process by which an abstract idea about a computer program, program is turned into an explicit data model or other object created in a programming language. A computable/addressable object—a ''resource''—is created in a system as a proxy for a non computable/addressable object. By means of reification, something that was previously implicit, unexpressed, and possibly inexpressible is explicitly formulated and made available to conceptual (logical or computational) manipulation. Informally, reification is often referred to as "making something a first-class citizen" within the scope of a particular system. Some aspect of a system can be reified at ''language design time'', which is related to Reflection (computer science), reflection in programming languages. It can be applied as a stepwise refinement at ''system design time''. Reification is one of the most frequently used techniques of conceptual analysis and knowledge representation. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immutable Object
In object-oriented (OO) and functional programming, an immutable object (unchangeable object) is an object whose state cannot be modified after it is created.Goetz et al. ''Java Concurrency in Practice''. Addison Wesley Professional, 2006, Section 3.4. Immutability This is in contrast to a mutable object (changeable object), which can be modified after it is created. In some cases, an object is considered immutable even if some internally used attributes change, but the object's state appears unchanging from an external point of view. For example, an object that uses to cache the results of expensive computations could still be considered an immutable object. Strings and other concrete objects are typically expressed as immutable objects to improve readability and runtime efficiency in object-oriented programming. Immutable objects are also useful because they are inherently thread-safe. Other benefits are that they are simpler to understand and reason about and offer higher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microservices
In software engineering, a microservice architecture is an architectural pattern that organizes an application into a collection of loosely coupled, fine-grained services that communicate through lightweight protocols. This pattern is characterized by the ability to develop and deploy services independently, improving modularity, scalability, and adaptability. However, it introduces additional complexity, particularly in managing distributed systems and inter-service communication, making the initial implementation more challenging compared to a monolithic architecture. Definition There is no single, universally agreed-upon definition of microservices. However, they are generally characterized by a focus on modularity, with each service designed around a specific business capability. These services are loosely coupled, independently deployable, and often developed and scaled separately, enabling greater flexibility and agility in managing complex systems. Microservices architec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NetKernel
NetKernel is a British software company and software platform by the same name that is used for High Performance Computing, Enterprise Application Integration, and Energy Efficient Computation. It allows developers to cleanly separate code from architecture. It can be used as an application server, embedded in a Java container or employed as a cloud computing platform. As a platform, it is an implementation of the resource-oriented computing (ROC) abstraction. ROC is a ''logical'' computing model that resides on top of but is completely isolated from the ''physical'' realm of code and objects. In ROC, information and services are identified by logical addresses which are resolved to physical endpoints for the duration of a request and then released. Logical indirect addressing results in flexible systems that can be changed while the system is in operation. In NetKernel, the boundary between the logical and physical layers is intermediated by an operation-system caliber microkernel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
