Software transactional memory

In computer science, software transactional memory (STM) is a concurrency control mechanism analogous to database transactions for controlling access to shared memory in concurrent computing. It functions as an alternative to lock-based synchronization, and is typically implemented in a lock-free way. A transaction in this context is a piece of code that executes a series of reads and writes to shared memory. These reads and writes logically occur at a single instant in time; intermediate states are not visible to other (successful) transactions. The idea of providing hardware support for transactions originated in a 1986 paper and patent by Tom Knight. The idea was popularized by Maurice Herlihy and J. Eliot B. Moss. In 1995 Nir Shavit and Dan Touitou extended this idea to software-only transactional memory (STM). STM has recently been the focus of intense research and support for practical implementations is growing.

Online transaction processing

Online transaction processing, or OLTP, refers to a class of systems that facilitate and manage transaction-oriented applications, typically for data entry and retrieval transaction processing. The term is somewhat ambiguous; some understand a "transaction" in the context of computer or database transactions, while others (such as the Transaction Processing Performance Council) define it in terms of business or commercial transactions.OLTP has also been used to refer to processing in which the system responds immediately to user requests. An automatic teller machine (ATM) for a bank is an example of a commercial transaction processing application.

The technology is used in a number of industries, including banking, airlines, mailorder, supermarkets, and manufacturing. Applications include electronic banking, order processing, employee time clock systems, e-commerce, and eTrading.

Relational model

The relational model for database management is a database model based on first-order predicate logic, first formulated and proposed in 1969 by Edgar Codd.

Its core idea is to describe a database as a collection of predicates over a finite set of predicate variables, describing constraints on the possible values and combinations of values. The content of the database at any given time is a finite model (logic) of the database, i.e. a set of relations, one per predicate variable, such that all predicates are satisfied. A request for information from the database (a database query) is also a predicate.

The purpose of the relational model is to provide a declarative method for specifying data and queries: we directly state what information the database contains and what information we want from it, and let the database management system software take care of describing data structures for storing the data and retrieval procedures for getting queries answered.

Webmail

In addition to the fat client e-mail clients and small MUAs, there are also Web-based e-mail programs called webmail. Webmail has several advantages which include the ability to send and receive e-mail from anywhere using a single application: a web browser. This eliminates the need to configure an email client. Significant examples of e-mail services which also provide the user a webmail interface are Hotmail, Gmail, AOL and Yahoo. The main drawbacks of webmail are that user interactions are subject to network response and that there is no offline capability. For instance, while webmail generally provides the best experience over broadband, a fat client can provide a satisfactory experience over dialup, and messages can be searched and viewed without an internet connection.

Rogue software

Rogue security software is software that uses malware (malicious software) or malicious tools to advertise or install itself or to force computer users to pay for removal of nonexistent spyware. Rogue software will often install a trojan horse to download a trial version, or it will do other unwanted things. The first and still most comprehensive study of rogue and real antispyware programs was carried out by Eric L. Howes

Virus removal

One possibility on Windows Me, Windows XP and Windows Vista is a tool known as System Restore, which restores the registry and critical system files to a previous checkpoint. Often a virus will cause a system to hang, and a subsequent hard reboot will render a system restore point from the same day corrupt. Restore points from previous days should work provided the virus is not designed to corrupt the restore files. Some viruses, however, disable system restore and other important tools such as Task Manager and Command Prompt. An example of a virus that does this is CiaDoor.

Administrators have the option to disable such tools from limited users for various reasons. The virus modifies the registry to do the same, except, when the Administrator is controlling the computer, it blocks all users from accessing the tools. When an infected tool activates it gives the message "Task Manager has been disabled by your administrator.", even if the user trying to open the program is the administrator.

Users running a Microsoft operating system can go to Microsoft's website to run a free scan, if they have their 20-digit registration number.

Psycho-Cybernetics

Psycho-Cybernetics is a classic self-help book, written by Maxwell Maltz in 1960 and published by the non-profit Psycho-Cybernetics Foundation. Motivational and self-help experts in personal development, including Zig Ziglar, Tony Robbins, Brian Tracy have based their techniques on Maxwell Maltz. Many of the psychological methods of training elite athletes are based on the concepts in Psycho-Cybernetics as well. The book combines the cognitive behavioral technique of teaching an individual how to regulate self-concept developed by Prescott Lecky with the cybernetics of Norbert Wiener and John von Neumann. The book defines the mind-body connection as the core in succeeding in attaining personal goals.

Maltz found that his plastic surgery patients often had expectations that were not satisfied by the surgery, so he pursued a means of helping them set the goal of a positive outcome through visualization of that positive outcome. Maltz became interested in why setting goals works. He learned that the power of of self-affirmation and mental visualisation techniques used the connection between the mind and the body. He specified techniques to develop a positive inner goal as a means of developing a positive outer goal. This concentration on inner attitudes is essential to his approach, as a person's outer success can never rise above the one visualized internally.

Systems psychology

Systems psychology is a branch of applied psychology that studies human behaviour and experience in complex systems. It is inspired by systems theory and systems thinking, and based on the theoretical work of Roger Barker, Gregory Bateson, Humberto Maturana and others. It is an approach in psychology, in which groups and individuals, are considered as systems in homeostasis. Alternative terms here are "systemic psychology", "systems behavior", and "systems-based psychology".

Ecosystem

The term ecosystem was coined in 1930 by Roy Clapham, to denote the physical and biological components of an environment considered in relation to each other as a unit. British ecologist Arthur Tansley later refined the term, describing it as the interactive system established between biocoenosis (a group of living creatures) and their biotope (the environment in which they live).

Central to the ecosystem concept is the idea that living organisms are continually engaged in a set of relationships with every other element constituting the environment in which they exist. The human ecosystem concept is then grounded in the deconstruction of the human/nature dichotomy, and the emergent premise that all species are ecologically integrated with each other, as well as with the abiotic constituents of their biotope.

Ecological Systems Theory

Ecological Systems Theory, also called "Development in Context" or "Human Ecology" theory, specifies four types of nested environmental systems, with bi-directional influences within and between the systems. The theory was developed by Urie Bronfenbrenner, generally regarded as one of the world's leading scholars in the field of developmental psychology. Later a fifth system was added:

* Microsystem: Immediate environments (family, school, peer group, neighborhood, and childcare environments)
* Mesosystem: A system comprised of connections between immediate environments (i.e., a child’s home and school)
* Exosystem: External environmental settings which only indirectly affect development (such as parent's workplace)
* Macrosystem: The larger cultural context (Eastern vs. Western culture, national economy, political culture, subculture)
* Chronosystem: The patterning of environmental events and transitions over the course of life.

The person's own biology may be considered part of the microsystem; thus the theory has recently sometimes been called "Bio-Ecological Systems Theory." Each system contains roles, norms, and rules that can powerfully shape development.

Evolutionary robotics

Evolutionary Robotics (ER) is a methodology that uses evolutionary computation to develop controllers for autonomous robots. Algorithms in ER frequently operate on populations of candidate controllers, initially selected from some distribution. This population is then repeatedly modified according to a fitness function. In the case of genetic algorithms (or "GAs"), a common method in evolutionary computation, the population of candidate controllers is repeatedly grown according to crossover, mutation and other GA operators and then culled according to the fitness function. The candidate controllers used in ER applications may be drawn from some subset of the set of artificial neural networks, although some applications (including SAMUEL, developed at the Naval Center for Applied Research in Artificial Intelligence) use collections of "IF THEN ELSE" rules as the constituent parts of an individual controller. It is theoretically possible to use any set of symbolic formulations of a control laws (sometimes called a policies in the machine learning community) as the space of possible candidate controllers. It is worth noting that artificial neural networks can also be used for robot learning outside of the context of evolutionary robotics. In particular, other forms of reinforcement learning can be used for learning robot controllers.

Containerization

Although having its origins in the late 1780s or earlier, the global standardisation of containers and container handling equipment was one of the important innovations in 20th century logistics.

By the 1830s, railroads on several continents were carrying containers that could be transferred to trucks or ships, but these containers were invariably small by today's standards. Originally used for shipping coal on and off barges, 'loose boxes' were used to containerize coal from the late 1780s, on places like the Bridgewater Canal. By the 1840's, iron boxes were in use as well as wooden ones. The early 1900s saw the adoption of closed container boxes designed for movement between road and rail.

Marine Cargo Types

There is a wide range of marine cargoes at seaport terminals operated. The primary types are these:

* Containers are the largest and fastest growing cargo category at most ports worldwide. Containerized cargo includes everything from auto parts and machinery components to shoes, toys, and frozen meat and seafood.

* Automobiles are handled at many ports.

* Project cargo and heavy lift cargo may include items such as manufacturing equipment, factory components, power equipment such as generators and wind turbines, military equipment or almost any other oversized or overweight cargo too big or too heavy to fit into a container.

* Break bulk cargo is typically material stacked on wooden pallets and lifted into and out of the hold of a vessel by cranes on the dock or aboard the ship itself. The volume of break bulk cargo has declined dramatically worldwide as containerization has grown.

* Bulk Cargoes, such as salt, oil, tallow, and Scrap metal, are usually defined as commodities that are neither on pallets nor in containers, and which are not handled as individual pieces, the way heavy-lift and project cargoes are. Alumina, grain, gypsum, logs and wood chips, for instance, are bulk cargoes.

Islamic Golden Age

The Islamic Golden Age, also sometimes known as the Islamic Renaissance, is traditionally dated from the 8th century to the 13th century, though some have extended it to the 15th or 16th centuries. During this period, engineers, scholars and traders in the Islamic world contributed to the arts, agriculture, economics, industry, law, literature, navigation, philosophy, sciences, and technology, both by preserving and building upon earlier traditions and by adding inventions and innovations of their own. Howard R. Turner writes: "Muslim artists and scientists, princes and laborers together created a unique culture that has directly and indirectly influenced societies on every continent."

Object database

In an object oriented database, information is represented in the form of objects as used in object-oriented programming. When database capabilities are combined with object programming language capabilities, the result is an object database management system (ODBMS). An ODBMS makes database objects appear as programming language objects in one or more object programming languages. An ODBMS extends the programming language with transparently persistent data, concurrency control, data recovery, associative queries, and other capabilities.

Prototyping

Prototyping is the process of quickly putting together a working model (a prototype) in order to test various aspects of a design, illustrate ideas or features and gather early user feedback. Prototyping is often treated as an integral part of the system design process, where it is believed to reduce project risk and cost. Often one or more prototypes are made in a process of iterative and incremental development where each prototype is influenced by the performance of previous designs, in this way problems or deficiencies in design can be corrected. When the prototype is sufficiently refined and meets the functionality, robustness, manufacturability and other design goals, the product is ready for production.

Database security

Database security is the system, processes, and procedures that protect a database from unintended activity. Unintended activity can be categorized as authenticated misuse, malicious attacks or inadvertent mistakes made by authorized individuals or processes. Database security is also a specialty within the broader discipline of computer security.

Traditionally databases have been protected from external connections by firewalls or routers on the network perimeter with the database environment existing on the internal network opposed to being located within a demilitarized zone. Additional network security devices that detect and alert on malicious database protocol traffic include network intrusion detection systems along with host-based intrusion detection systems.

Transparent and non-transparent proxy server

The term "transparent proxy" is most often used incorrectly to mean "intercepting proxy" (because the client does not need to configure a proxy and cannot directly detect that its requests are being proxied).

However, RFC 2616 (Hypertext Transfer Protocol -- HTTP/1.1) offers different definitions:

"A 'transparent proxy' is a proxy that does not modify the request or response beyond what is required for proxy authentication and identification".
"A 'non-transparent proxy' is a proxy that modifies the request or response in order to provide some added service to the user agent, such as group annotation services, media type transformation, protocol reduction, or anonymity filtering".

SQL/XML, or XML-Related Specifications

The SQL/XML, or XML-Related Specifications, extension to the SQL standard is defined by ISO/IEC 9075-14:2003. SQL/XML specifies SQL-based extensions for using XML in conjunction with SQL. The XML data type is introduced, as well as several routines, functions, and XML-to-SQL data type mappings to support manipulation and storage of XML in a SQL database.

The SQL/XML specification includes functions to construct XML data. These functions allow the user to construct new XML elements or attributes with values e.g. from relational tables. Other functions such as XMLCONCAT or XMLAGG can be used to combine small XML fragments into larger ones. The list of available construction functions includes:

* XMLELEMENT
* XMLATTRIBUTES
* XMLFOREST
* XMLCONCAT
* XMLNAMESPACES
* XMLCOMMENT
* XMLPI
* XMLDOCUMENT
* XMLAGG
* etc.

Pharmacognosy

Pharmacognosy is the study of medicines derived from natural sources. The American Society of Pharmacognosy defines pharmacognosy as "the study of the physical, chemical, biochemical and biological properties of drugs, drug substances or potential drugs or drug substances of natural origin as well as the search for new drugs from natural sources."