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Reference Count
In computer science, reference counting is a programming technique of storing the number of references, pointers, or handles to a resource, such as an object, a block of memory, disk space, and others. In garbage collection algorithms, reference counts may be used to deallocate objects that are no longer needed. Advantages and disadvantages The main advantage of the reference counting over tracing garbage collection is that objects are reclaimed ''as soon as'' they can no longer be referenced, and in an incremental fashion, without long pauses for collection cycles and with clearly defined lifetime of every object. In real-time applications or systems with limited memory, this is important to maintain responsiveness. Reference counting is also among the simplest forms of memory management to implement. It also allows for effective management of non-memory resources such as operating system objects, which are often much scarcer than memory (tracing garbage collection systems u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical disciplines (including the design and implementation of Computer architecture, hardware and Computer programming, software). Computer science is generally considered an area of research, academic research and distinct from computer programming. Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and for preventing Vulnerability (computing), security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Progr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertex (graph Theory)
In discrete mathematics, and more specifically in graph theory, a vertex (plural vertices) or node is the fundamental unit of which graphs are formed: an undirected graph consists of a set of vertices and a set of edges (unordered pairs of vertices), while a directed graph consists of a set of vertices and a set of arcs (ordered pairs of vertices). In a diagram of a graph, a vertex is usually represented by a circle with a label, and an edge is represented by a line or arrow extending from one vertex to another. From the point of view of graph theory, vertices are treated as featureless and indivisible objects, although they may have additional structure depending on the application from which the graph arises; for instance, a semantic network is a graph in which the vertices represent concepts or classes of objects. The two vertices forming an edge are said to be the endpoints of this edge, and the edge is said to be incident to the vertices. A vertex ''w'' is said to be ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Bevan (mathematician)
David Bevan is an English mathematician, computer scientist and software developer. He is known for Bevan's theorem, which gives the asymptotic enumeration of grid classes of permutations and for his work on enumerating the class of permutations avoiding the pattern 1324. He is also known for devising weighted reference counting, an approach to computer memory management that is suitable for use in distributed systems. Work and research Bevan is a lecturer in combinatorics in the department of Mathematics and Statistics at the University of Strathclyde. He has degrees in mathematics and computer science from the University of Oxford and a degree in theology from the London School of Theology. He received his PhD in mathematics from The Open University in 2015; his thesis, ''On the growth of permutation classes'', was supervised by Robert Brignall. In 1987, as a research scientist at GEC's Hirst Research Centre in Wembley, he developed an approach to computer memory management ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACM Transactions On Programming Languages And Systems
The ''ACM Transactions on Programming Languages and Systems'' (''TOPLAS'') is a bimonthly, open access, peer-reviewed scientific journal on the topic of programming languages published by the Association for Computing Machinery. Background Published since 1979, the journal's scope includes programming language design, implementation, and semantics of programming languages, compilers and interpreters, run-time systems, storage allocation and garbage collection, and formal specification, testing, and verification of software. It is indexed in Scopus and SCImago. The editor-in-chief is Andrew Myers (Cornell University). According to the ''Journal Citation Reports'', the journal had a 2020 impact factor of 0.410. References External links * TOPLASat ACM Digital Library TOPLASat DBLP DBLP is a computer science bibliography website. Starting in 1993 at Universität Trier in Germany, it grew from a small collection of HTML files and became an organization hosting a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycle Detection (graph Theory)
In graph theory, a cycle in a graph is a non-empty trail in which only the first and last vertices are equal. A directed cycle in a directed graph is a non-empty directed trail in which only the first and last vertices are equal. A graph without cycles is called an ''acyclic graph''. A directed graph without directed cycles is called a ''directed acyclic graph''. A connected graph without cycles is called a ''tree''. Definitions Circuit and cycle * A circuit is a non-empty trail in which the first and last vertices are equal (''closed trail''). : Let be a graph. A circuit is a non-empty trail with a vertex sequence . * A cycle or simple circuit is a circuit in which only the first and last vertices are equal. Directed circuit and directed cycle * A directed circuit is a non-empty directed trail in which the first and last vertices are equal (''closed directed trail''). : Let be a directed graph. A directed circuit is a non-empty directed trail with a vertex sequence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graph (abstract Data Type)
In computer science, a graph is an abstract data type that is meant to implement the undirected graph and directed graph concepts from the field of graph theory within mathematics. A graph data structure consists of a finite (and possibly mutable) set of ''vertices'' (also called ''nodes'' or ''points''), together with a set of unordered pairs of these vertices for an undirected graph or a set of ordered pairs for a directed graph. These pairs are known as ''edges'' (also called ''links'' or ''lines''), and for a directed graph are also known as ''edges'' but also sometimes ''arrows'' or ''arcs''. The vertices may be part of the graph structure, or may be external entities represented by integer indices or references. A graph data structure may also associate to each edge some ''edge value'', such as a symbolic label or a numeric attribute (cost, capacity, length, etc.). Operations The basic operations provided by a graph data structure ''G'' usually include:See, e.g. , Sectio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cocoa (API)
Cocoa is Apple's native object-oriented application programming interface (API) for its desktop operating system macOS. Cocoa consists of the Foundation Kit, Application Kit, and Core Data frameworks, as included by the Cocoa.h header file, and the libraries and frameworks included by those, such as the C standard library and the Objective-C runtime.Mac Technology Overview: OS X Frameworks Developer.apple.com. Retrieved on September 18, 2013. Cocoa applications are typically developed using the development tools provided by Apple, specifically (formerly [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hard Link
In computing, a hard link is a directory entry (in a directory-based file system) that associates a name with a file. Thus, each file must have at least one hard link. Creating additional hard links for a file makes the contents of that file accessible via additional paths (i.e., via different names or in different directories). This causes an alias effect: a process can open the file by any one of its paths and change its content. By contrast, a soft link or “shortcut” to a file is not a direct link to the data itself, but rather a reference to a hard link or another soft link. Every directory is itself a special file, only it contains a list of file names. Hence, multiple hard links to directories are possible, which could create a circular directory structure, rather than a branching structure like a tree. For that reason, some file systems forbid the creation of hard links to directories. POSIX-compliant operating systems, such as Linux, Android, macOS, and the Windo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Operations
In concurrent programming, an operation (or set of operations) is linearizable if it consists of an ordered list of invocation and response events (event), that may be extended by adding response events such that: # The extended list can be re-expressed as a sequential history (is serializable). # That sequential history is a subset of the original unextended list. Informally, this means that the unmodified list of events is linearizable if and only if its invocations were serializable, but some of the responses of the serial schedule have yet to return. In a concurrent system, processes can access a shared object at the same time. Because multiple processes are accessing a single object, there may arise a situation in which while one process is accessing the object, another process changes its contents. Making a system linearizable is one solution to this problem. In a linearizable system, although operations overlap on a shared object, each operation appears to take place i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erez Petrank
Erez Petrank is a computer scientist whose notable research contributions are in the fields of programming languages and computer systems (mostly on memory management), cryptography (mostly on theoretical foundations), computational complexity, and parallel computing. Petrank is currently (2017) a professor at the computer science department at the Technion - Israel Institute of Technology. Petrank has published more than seventy papers in top conferences and journals with more than 5000 citations and an h-index of 38 (computed by Google Scholar). He has served as the program chair of the International Symposium on Memory Management and of the ACM SIGPLAN/SIGOPS International Conference on Virtual Execution Environments (VEE). From 2009 to 2012, Petrank served on the Association for Computing Machinery SIGPLAN SIGPLAN is the Association for Computing Machinery's Special Interest Group on programming languages. Conferences * Principles of Programming Languages (POPL) * Progr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACM SIGPLAN Notices
SIGPLAN is the Association for Computing Machinery's Special Interest Group on programming languages. Conferences * Principles of Programming Languages (POPL) * Programming Language Design and Implementation (PLDI) * International Symposium on Memory Management (ISMM) * Languages, Compilers, and Tools for Embedded Systems (LCTES) * Symposium on Principles and Practice of Parallel Programming (PPoPP) * International Conference on Functional Programming (ICFP) * Systems, Programming, Languages, and Applications: Software for Humanity (SPLASH) * Object-Oriented Programming, Systems, Languages, and Applications (OOPSLA) * History of Programming Languages (HOPL) * Dynamic Languages Symposium (DLS) Associated journals * ACM Transactions on Architecture and Code Optimization * ACM Transactions on Programming Languages and Systems Proceedings of the ACM on Programming Languages Newsletters * SIGPLAN Notices - Home pageat ACM * Fortran Forum - * Lisp Pointers (final issue 1995) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Baker (computer Scientist)
Henry Givens Baker Jr. is an American computer scientist who has made contributions in garbage collection, functional programming languages, and linear logic. He was one of the founders of Symbolics, a company that designed and manufactured a line of Lisp machines. In 2006 he was recognized as a Distinguished Scientist by the Association for Computing Machinery. He is notable for his research in garbage collection, particularly Baker's real-time copying collector, and on the Actor model. Baker received his B.Sc. (1969), S.M. (1973), E.E. (1973), and Ph.D. (1978) degrees at M.I.T. The Chicken Scheme compiler Chicken (stylized as CHICKEN) is a programming language, specifically a compiler and interpreter which implement a dialect of the programming language Scheme, and which compiles Scheme source code to standard C. It is mostly R5RS compliant an ... was inspired by an innovative design of Baker's. Bibliography * * * * * References External links Henry Baker's Archive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
