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36-496: In the System/360 , other than the 360/67 , and System/370 architectures, the general-purpose registers were 32 bits wide, the machine did 32-bit arithmetic operations, and addresses were always stored in 32-bit words, so the architecture was considered 32-bit , but the machines ignored the top 8 bits of the address resulting in 24-bit addressing. Much of System/360's and System/370's large installed code base relied on

72-495: A 24-bit logical address ; In particular, a heavily used machine instruction, LA , Load Address, explicitly cleared the top eight bits of the address being placed in a register. If the 24-bit limit were to be removed, this would create migration problems for existing software. This was addressed by adding an addressing mode bit to the Program Status Word controlling whether the program runs in 24-bit mode, in which

108-486: A body of water vapor) in steam engines , in regard to the system's ability to do work when heat is applied to it. The working substance could be put in contact with either a boiler, a cold reservoir (a stream of cold water), or a piston (on which the working body could do work by pushing on it). In 1850, the German physicist Rudolf Clausius generalized this picture to include the concept of the surroundings and began to use

144-416: A call), BASSM is used as BASSM 14,15 , where the linkage address and mode are saved in register 14, and a branch is taken to the subroutine address and mode specified in register 15. Somewhat similarly to BCR 15,14 (the 24-bit-only form of an unconditional return), BSM is used as BSM 0,14 , where 0 indicates that the current mode is not saved (the program is leaving the subroutine, anyway), and

180-606: A car, a coffeemaker , or Earth . A closed system exchanges energy, but not matter, with its environment; like a computer or the project Biosphere 2 . An isolated system exchanges neither matter nor energy with its environment. A theoretical example of such a system is the Universe . An open system can also be viewed as a bounded transformation process, that is, a black box that is a process or collection of processes that transform inputs into outputs. Inputs are consumed; outputs are produced. The concept of input and output here

216-444: A major defect: they must be premised on one or more fundamental assumptions upon which additional knowledge is built. This is in strict alignment with Gödel's incompleteness theorems . The Artificial system can be defined as a "consistent formalized system which contains elementary arithmetic". These fundamental assumptions are not inherently deleterious, but they must by definition be assumed as true, and if they are actually false then

252-410: A return to the caller at the address and mode specified in register 14 is to be taken. System/370 initially supported only 24-bit physical addresses; the extended real address feature extended this to 26-bit addresses. System/370-XA changed the page table entry format to support 19 bits of page frame address; pages are 4 KB in 370-XA, so combining a 19-bit page frame address with a 12-bit offset within

288-434: A set of rules to form a unified whole. A system, surrounded and influenced by its environment , is described by its boundaries, structure and purpose and is expressed in its functioning. Systems are the subjects of study of systems theory and other systems sciences . Systems have several common properties and characteristics, including structure, function(s), behavior and interconnectivity. The term system comes from

324-588: A system understanding its kind is crucial, and defined natural and designed , i. e. artificial, systems. For example, natural systems include subatomic systems, living systems , the Solar System , galaxies , and the Universe , while artificial systems include man-made physical structures, hybrids of natural and artificial systems, and conceptual knowledge. The human elements of organization and functions are emphasized with their relevant abstract systems and representations. Artificial systems inherently have

360-544: A variety of areas, such as psychology, biology, medicine, communication, business, technology, computer science, engineering, and social sciences. Themes commonly stressed in system science are (a) holistic view, (b) interaction between a system and its embedding environment , and (c) complex (often subtle) trajectories of dynamic behavior that sometimes are stable (and thus reinforcing), while at various ' boundary conditions ' can become wildly unstable (and thus destructive). Concerns about Earth-scale biosphere/geosphere dynamics

396-456: Is George Boole 's Boolean operators. Other examples relate specifically to philosophy, biology, or cognitive science. Maslow's hierarchy of needs applies psychology to biology by using pure logic. Numerous psychologists, including Carl Jung and Sigmund Freud developed systems that logically organize psychological domains, such as personalities, motivations, or intellect and desire. In 1988, military strategist, John A. Warden III introduced

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432-428: Is a transdisciplinary field that is concerned with understanding simple and complex systems in nature and society , which leads to the advancements of formal, natural, social, and applied attributions throughout engineering , technology and science , itself. To systems scientists, the world can be understood as a system of systems. The field aims to develop transdisciplinary foundations that are applicable in

468-546: Is a hardware system, software system , or combination, which has components as its structure and observable inter-process communications as its behavior. There are systems of counting, as with Roman numerals , and various systems for filing papers, or catalogs, and various library systems, of which the Dewey Decimal Classification is an example. This still fits with the definition of components that are connected together (in this case to facilitate

504-453: Is an example of the nature of problems to which systems science seeks to contribute meaningful insights. The systems sciences are a broad array of fields. One way of conceiving of these is in three groups: fields that have developed systems ideas primarily through theory; those that have done so primarily through practical engagements with problem situations; and those that have applied ideas for other disciplines. The soft systems methodology

540-448: Is very broad. For example, an output of a passenger ship is the movement of people from departure to destination. A system comprises multiple views . Human-made systems may have such views as concept, analysis , design , implementation , deployment, structure, behavior, input data, and output data views. A system model is required to describe and represent all these views. A systems architecture, using one single integrated model for

576-1938: The Five Ring System model in his book, The Air Campaign , contending that any complex system could be broken down into five concentric rings. Each ring—leadership, processes, infrastructure, population and action units—could be used to isolate key elements of any system that needed change. The model was used effectively by Air Force planners in the Iran–Iraq War . In the late 1990s, Warden applied his model to business strategy. Systems science Collective intelligence Collective action Self-organized criticality Herd mentality Phase transition Agent-based modelling Synchronization Ant colony optimization Particle swarm optimization Swarm behaviour Social network analysis Small-world networks Centrality Motifs Graph theory Scaling Robustness Systems biology Dynamic networks Evolutionary computation Genetic algorithms Genetic programming Artificial life Machine learning Evolutionary developmental biology Artificial intelligence Evolutionary robotics Reaction–diffusion systems Partial differential equations Dissipative structures Percolation Cellular automata Spatial ecology Self-replication Conversation theory Entropy Feedback Goal-oriented Homeostasis Information theory Operationalization Second-order cybernetics Self-reference System dynamics Systems science Systems thinking Sensemaking Variety Ordinary differential equations Phase space Attractors Population dynamics Chaos Multistability Bifurcation Rational choice theory Bounded rationality Systems science , also referred to as systems research , or, simply, systems ,

612-527: The Latin word systēma , in turn from Greek σύστημα systēma : "whole concept made of several parts or members, system", literary "composition". In the 19th century, the French physicist Nicolas Léonard Sadi Carnot , who studied thermodynamics , pioneered the development of the concept of a system in the natural sciences . In 1824, he studied the system which he called the working substance (typically

648-597: The 24/31 bit version of a call where the linkage address including the mode is saved and a branch is taken to an address in a possibly different mode, and BSM , Branch and Set Mode, the 24/31 bit version of a return, where the return is directly to the previously saved linkage address and in its previous mode. Taken together, BASSM and BSM allow 24-bit calls to 31-bit (and return to 24-bit), 31-bit calls to 24-bit (and return to 31-bit), 24-bit calls to 24-bit (and return to 24-bit) and 31-bit calls to 31-bit (and return to 31-bit). Like BALR 14,15 (the 24-bit-only form of

684-661: The ability to interact with local and remote operators. A subsystem description is a system object that contains information defining the characteristics of an operating environment controlled by the system. The data tests are performed to verify the correctness of the individual subsystem configuration data (e.g. MA Length, Static Speed Profile, …) and they are related to a single subsystem in order to test its Specific Application (SA). There are many kinds of systems that can be analyzed both quantitatively and qualitatively . For example, in an analysis of urban systems dynamics , A . W. Steiss defined five intersecting systems, including

720-462: The allocation and scarcity of resources. The international sphere of interacting states is described and analyzed in systems terms by several international relations scholars, most notably in the neorealist school . This systems mode of international analysis has however been challenged by other schools of international relations thought, most notably the constructivist school , which argues that an over-large focus on systems and structures can obscure

756-410: The description of multiple views, is a kind of system model. A subsystem is a set of elements, which is a system itself, and a component of a larger system. The IBM Mainframe Job Entry Subsystem family ( JES1 , JES2 , JES3 , and their HASP / ASP predecessors) are examples. The main elements they have in common are the components that handle input, scheduling, spooling and output; they also have

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792-399: The distinction between them is often elusive. An economic system is a social institution which deals with the production , distribution and consumption of goods and services in a particular society . The economic system is composed of people , institutions and their relationships to resources, such as the convention of property . It addresses the problems of economics , like

828-404: The flow of information). System can also refer to a framework, aka platform , be it software or hardware, designed to allow software programs to run. A flaw in a component or system can cause the component itself or an entire system to fail to perform its required function, e.g., an incorrect statement or data definition . In engineering and physics , a physical system is the portion of

864-741: The instruction length code, the condition code and the program mask, in the top byte of the return address. A BAS , Branch and Save, instruction was added to allow 31-bit return addresses. BAS , and its register-register equivalent, BASR , Branch and Save Register, was part of the instruction set of the 360/67, which was the only System/360 model to allow addresses longer than 24 bits. These instructions were maintained, but were modified and extended for 31-bit addressing. Additional instructions in support of allowing calls between 24-bit-addressing and 31-bit-addressing code include two new register-register call/return instructions which also effect an addressing mode change, BASSM , Branch and Save and Set Mode,

900-464: The notion of organizations as systems in his book The Fifth Discipline . Organizational theorists such as Margaret Wheatley have also described the workings of organizational systems in new metaphoric contexts, such as quantum physics , chaos theory , and the self-organization of systems . There is also such a thing as a logical system . An obvious example is the calculus developed simultaneously by Leibniz and Isaac Newton . Another example

936-517: The page produces a 31-bit physical address. Channel command words can be in one of two formats, with format 0 being the System/370 format, with a 24-bit data address, and format 1 being an additional format, with a 31-bit data address. System/370-XA introduced a channel subsystem that performed I/O queuing previously done by the operating system. System A system is a group of interacting or interrelated elements that act according to

972-400: The physical subsystem and behavioral system. For sociological models influenced by systems theory, Kenneth D. Bailey defined systems in terms of conceptual , concrete , and abstract systems, either isolated , closed , or open . Walter F. Buckley defined systems in sociology in terms of mechanical , organic , and process models . Bela H. Banathy cautioned that for any inquiry into

1008-405: The role of individual agency in social interactions. Systems-based models of international relations also underlie the vision of the international sphere held by the liberal institutionalist school of thought, which places more emphasis on systems generated by rules and interaction governance, particularly economic governance. In computer science and information science , an information system

1044-1207: The system is not as structurally integral as is assumed (i.e. it is evident that if the initial expression is false, then the artificial system is not a "consistent formalized system"). For example, in geometry this is very evident in the postulation of theorems and extrapolation of proofs from them. George J. Klir maintained that no "classification is complete and perfect for all purposes", and defined systems as abstract, real, and conceptual physical systems , bounded and unbounded systems , discrete to continuous, pulse to hybrid systems , etc. The interactions between systems and their environments are categorized as relatively closed and open systems . Important distinctions have also been made between hard systems—–technical in nature and amenable to methods such as systems engineering , operations research, and quantitative systems analysis—and soft systems that involve people and organizations, commonly associated with concepts developed by Peter Checkland and Brian Wilson through soft systems methodology (SSM) involving methods such as action research and emphasis of participatory designs. Where hard systems might be identified as more scientific ,

1080-552: The system. There are natural and human-made (designed) systems. Natural systems may not have an apparent objective but their behavior can be interpreted as purposeful by an observer. Human-made systems are made with various purposes that are achieved by some action performed by or with the system. The parts of a system must be related; they must be "designed to work as a coherent entity"—otherwise they would be two or more distinct systems. Most systems are open systems , exchanging matter and energy with their respective surroundings; like

1116-462: The term working body when referring to the system. The biologist Ludwig von Bertalanffy became one of the pioneers of the general systems theory . In 1945 he introduced models, principles, and laws that apply to generalized systems or their subclasses, irrespective of their particular kind, the nature of their component elements, and the relation or 'forces' between them. In the late 1940s and mid-50s, Norbert Wiener and Ross Ashby pioneered

IBM System/370-XA - Misplaced Pages Continue

1152-492: The top eight bits of virtual addresses are ignored, or 31-bit mode, in which only the uppermost bit of virtual addresses are ignored. Several reasons were given for the choice of 31 bits instead of 32 bits: Certain machine instructions in this 31-bit addressing mode alter the addressing mode bit. For example, the original subroutine call instructions BAL , Branch and Link, and its register-register equivalent, BALR , Branch and Link Register, store certain status information,

1188-1003: The universe that is being studied (of which a thermodynamic system is one major example). Engineering also has the concept of a system referring to all of the parts and interactions between parts of a complex project. Systems engineering is the branch of engineering that studies how this type of system should be planned, designed, implemented, built, and maintained. Social and cognitive sciences recognize systems in models of individual humans and in human societies. They include human brain functions and mental processes as well as normative ethics systems and social and cultural behavioral patterns. In management science , operations research and organizational development , human organizations are viewed as management systems of interacting components such as subsystems or system aggregates, which are carriers of numerous complex business processes ( organizational behaviors ) and organizational structures. Organizational development theorist Peter Senge developed

1224-463: The use of mathematics to study systems of control and communication , calling it cybernetics . In the 1960s, Marshall McLuhan applied general systems theory in an approach that he called a field approach and figure/ground analysis , to the study of media theory . In the 1980s, John Henry Holland , Murray Gell-Mann and others coined the term complex adaptive system at the interdisciplinary Santa Fe Institute . Systems theory views

1260-401: The world as a complex system of interconnected parts. One scopes a system by defining its boundary ; this means choosing which entities are inside the system and which are outside—part of the environment . One can make simplified representations ( models ) of the system in order to understand it and to predict or impact its future behavior. These models may define the structure and behavior of

1296-700: Was developed in England by academics at the University of Lancaster Systems Department through a ten-year action research programme. The main contributor is Peter Checkland (born 18 December 1930, in Birmingham, UK), a British management scientist and emeritus professor of systems at Lancaster University. Systems analysis branch of systems science that analyzes systems, the interactions within those systems, or interaction with its environment, often prior to their automation as computer models. Systems analysis

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