home Boilers What is a system examples. What is the system

What is a system examples. What is the system

What types of interactions are short-acting? Give examples of systems in which these forces operate

The weak interaction is less known outside a small circle of physicists and astronomers, but this in no way diminishes its importance. Suffice it to say that if it were not there, the Sun and other stars would go out, because in the reactions that ensure their glow, the weak interaction plays a very important role. The weak interaction is short-range: its radius is approximately 1000 times smaller than that of nuclear forces.

Strong interaction is the most powerful of all others. It defines connections only between hadrons. Nuclear forces acting between nucleons in an atomic nucleus are a manifestation of this type of interaction. It is about 100 times stronger than electromagnetic energy. Unlike the latter (as well as gravitational), it is, firstly, short-range at a distance greater than 10-15 m (on the order of the size of the nucleus), the corresponding forces between protons and neutrons, sharply decreasing, cease to bind them to each other. Secondly, it can be described satisfactorily only by means of three charges (colors) forming complex combinations.

The most important characteristic of a fundamental interaction is its range of action. The radius of action is the maximum distance between particles, beyond which their interaction can be neglected. At a small radius the interaction is called short-range, at a large radius it is called long-range. Strong and weak interactions are short-range. Their intensity decreases rapidly with increasing distance between particles. Such interactions occur at a short distance, inaccessible to perception by the senses. For this reason, these interactions were discovered later than others (only in the 20th century) using complex experimental setups. To explain the small radius of action of nuclear forces, the Japanese physicist H. Yukawa in 1935 put forward a hypothesis according to which solar energy. between nucleons (N) occurs due to the fact that they exchange with each other a certain particle with mass, similar to how the electromagnetic interaction between charged particles, according to quantum electrodynamics, is carried out through the exchange of “particles of light” - photons. It was assumed that there is a specific interaction leading to the emission and absorption of an intermediate particle - a carrier of nuclear forces. In other words, it was introduced new type interactions, which were later called strong interactions. Based on the known experimental radius of action of nuclear forces, Yukawa estimated the mass of the carrier particle c. V. This estimate is based on simple quantum mechanical considerations. According to quantum mechanics, the observation time of the system?t and the uncertainty in its energy?E are related by the relation: ?E?t Strong interactions h, where h is the Planck constant. Therefore, if a free nucleon emits a particle with mass m (i.e., the energy of the system changes according to the relativity formula of the theory by the amount?E = mc2, where c is the speed of light), then this can only happen for a time?t Strong interactions h/mc2 . During this time, a particle moving at a speed approaching the maximum possible speed of light c can travel a distance of the order of h/mc. Therefore, in order for the interaction between two particles to be carried out by exchanging a particle of mass m, the distance between these particles must be of the order of (or less) h/mc, i.e., the radius of action of the forces transferred by a particle with mass m must be h/mc. With a range of Strong Interactions of 10-13 cm, the mass of the carrier of nuclear forces should be about 300 me (where me is the mass of an electron), or approximately 6 times less than the mass of a nucleon. Such a particle was discovered in 1947 and called the pi-meson (pion, ?). Later it turned out that the picture of interaction is much more complex. It turned out that, in addition to charged?± and neutral?0-mesons with masses of 273 me and 264 me, respectively, the interaction is transmitted by a large number of other mesons with large masses: ?, ?, ?, K,..., etc. In addition, a certain contribution to S. century. (for example, between mesons and nucleons) gives an exchange of nucleons and antinucleons themselves and their excited states by baryon resonances. From the uncertainty relationship it follows that the exchange of particles with masses greater than the mass of the pion occurs at distances less than 10–13 cm, i.e., it determines the nature of the interaction. at short distances, the experimental study of various reactions with hadrons (such, for example, as reactions with charge transfer - “charge exchange”: ?- + р > ?0 + n, K- + р > K0 + n, etc.) allows in principle find out what contribution to S. century. gives an exchange of certain particles.

System(Greek systema - a whole made up of parts, a connection) - a set of interactions of elements united by unity of goals and forming a certain integrity; it is a purposeful set of interconnected elements of any nature; this is an object that is defined by sets of elements, transformations, rules for the formation of sequences of elements; it is an object consisting of elements whose properties cannot be reduced to the properties of the object itself.

Basic properties of systems: 1. The organized complexity of a system is characterized by the presence of relationships between elements (there are three types of connections: functionally necessary, redundant (reserve), synergetic (giving an increase in the effect of the system due to the interaction of elements)). 2. Decomposability. 3. The integrity of the system is the fundamental irreducibility of the properties of the system to the sum of the properties of its constituent elements, and, at the same time, the dependence of the properties of each element on its place and functions within the system. 4. Limitation of the system. The limitations of the system are associated with the external environment. The concept of external environment includes all systems of elements of any nature that influence the system or are under its influence. The task of localizing the system (determining its boundaries and essential connections) arises. There are open and closed systems. Open systems have connections with the external environment, closed systems do not. 5. Structural structure of the system. Structurality is the grouping of elements within a system according to a certain rule or principle into subsystems. The structure of a system is a set of connections between elements of the system, reflecting their interaction. There are two types of connections: horizontal and vertical. External connections directed into the system are called inputs, and connections from the system to the external environment are called outputs. Internal connections are connections between subsystems. 6. Functional orientation of the system, the functions of the system can be represented as a set of certain transformations, which are divided into two groups.

Types of systems: 1. A simple system is a system that consists of a small number of elements and does not have a branched structure (hierarchical levels cannot be distinguished). 2. A complex system is a system with a branched structure and a significant number of interconnected and interacting elements (subsystems). A complex dynamic system should be understood as integral objects developing in time and space, consisting of a large number of elements and connections and possessing properties that are absent in the elements and connections that form them. The structure of a system is a set of internal, stable connections between the elements of the system that determine its basic properties. Systems are: social, biological, mechanical, chemical, environmental, simple, complex, probabilistic, deterministic, stochastic. 3. Centralized system– a system in which a certain element (subsystem) plays a dominant role. 4. Decentralized system – a system in which there is no dominant subsystem. 5. Organizational system – a system that is a set of people or groups of people. 6. Open systems – those in which internal processes significantly depend on environmental conditions and themselves have a significant impact on its elements. 7. Closed (closed) systems – those in which internal processes are weakly connected with the external environment. The functioning of closed systems is determined by internal information. 8. Deterministic systems – systems in which the connections between elements and events are unambiguous, predetermined. 9. A probabilistic (stochastic) system is a system in which the connections between elements and events are ambiguous. The connections between elements are probabilistic in nature and exist in the form of probabilistic patterns. 10. Deterministic systems are a special case of probabilistic ones (Рв=1). 11. A dynamic system is a system whose nature is constantly changing. Moreover, the transition to a new state cannot occur instantly, but requires some time.

Stages of building systems: goal setting, decomposition of the goal into subgoals, determination of functions that ensure the achievement of the goal, synthesis of the structure that ensures the fulfillment of functions. Goals arise when there is a so-called problem situation (a problem situation is a situation that cannot be resolved by available means). Goal is the state towards which the tendency of an object’s movement is directed. Environment is the totality of all systems except the one that realizes a given goal. No system is completely closed. The interaction of the system with the environment is realized through external connections. A system element is a part of a system that has a certain functional significance. Connections can be input and output. They are divided into: informational, resource (managing).

System structure: represents a stable ordering of system elements and their connections in space and time. Structure can be material or formal. Formal structure is a set of functional elements and their relationships that are necessary and sufficient for the system to achieve specified goals. Material structure is the real content of the formal structure. Types of system structures: sequential or chain; hierarchical; cyclically closed (ring type); “wheel” type structure; "star"; lattice type structure.

A complex system is characterized: a single purpose of functioning; hierarchical management system; a large number of connections within the system; complex composition of the system; resistance to external and internal influencing factors; the presence of elements of self-regulation; the presence of subsystems.

Properties of complex systems : 1. Multi-level (part of the system is itself a system. The entire system, in turn, is part of a larger system); 2. The presence of an external environment (every system behaves depending on the external environment in which it is located. It is impossible to mechanically extend conclusions obtained about a system under one external conditions to the same system located under other external conditions); 3. Dynamic (in systems there is nothing immutable. All constants and static states are only abstractions that are valid within limited limits); 4. A person who has worked with any complex system for a long time may become confident that certain “obvious” changes, if made to the system, will lead to certain “obvious” improvements. When the changes are implemented, the system responds in a completely different way than expected. This happens when trying to reform the management of a large enterprise, when reforming the state, etc. The cause of such errors is a lack of information about the system as a result of an unconscious mechanistic approach. The methodological conclusion for such situations is that complex systems do not change in one circle; it is necessary to make many circles, at each of which small changes are made to the system, and studies of their results are carried out with mandatory attempts to identify and analyze new types of connections that appear in system; 5. Stability and aging (the stability of a system is its ability to compensate for external or internal influences aimed at destroying or rapidly changing the system. Aging is a deterioration in efficiency and gradual destruction of the system over a long period of time. 6. Integrity (the system has integrity, which is independent new entity. This entity organizes itself, influences the parts of the system and the connections between them, replaces them to preserve itself as an integrity, orients itself in the external environment, etc.); 7. Polystructurality is the presence of a large number of structures. Considering the system from different points of view, we will identify different structures in it. The polystructural nature of systems can be considered as their multidimensionality. The functional aspect reflects the behavior of the system and its parts only from the point of view of what they do, what function they perform. this does not take into account questions about how they do this and what they are physically like. It is only important that the functions of the individual parts combine to form the function of the system as a whole. The design aspect only covers issues of the physical layout of the system. Form is important here components, their material, their placement and joining in space, appearance systems. The technological aspect reflects how the functions of the parts of the system are performed.

Interactive board;
MS PowerPoint

During the classes:

I. Organizational moment (2 min.)

II. Updating knowledge (3 min.)

Checking homework.

III. Theoretical part (30 min.)

Systemology is the science of systems. What is the content of this science and what relation does it have to computer science, you will learn from this chapter.

System concept

Our world is filled with a variety of different objects. We often use the concepts “simple object” and “complex object”. Have you ever thought about the difference between simple and complex? At first glance, the answer appears obvious: a complex object consists of many simple ones. And the more such “details” it contains, the more complex the subject. For example, a brick is a simple object, but a building made of bricks is a complex object. Or again: a bolt, wheel, steering wheel and other parts of a car are simple objects, and the car itself, assembled from these parts, is a complex device. But is it only the number of details that makes the difference between simple and complex?

Let us formulate the definition of the main concept of systemology - the concept of a system:

A system is a complex object consisting of interconnected parts (elements) and existing as a single whole. Every system has a specific purpose (function, goal).

Consider a pile of bricks and a house built from those bricks. No matter how many bricks there are in a pile, it cannot be called a system, because there is no unity in it, no purposefulness. But a residential building has a very specific purpose - you can live in it. In the masonry of a house, the bricks are interconnected in a certain way, in accordance with the design. Of course, in the construction of a house, in addition to bricks, there are many other parts (boards, beams, windows, etc.), all of them are properly connected and form a single whole - the house.

Here's another example: a lot of bicycle parts and a bicycle assembled from them. A bicycle is a system. Its purpose is to be a vehicle for humans.

— expediency. This is the purpose of the system, the main function it performs.

System structure

Any system is determined not only by the composition of its parts, but also by the order and method of combining these parts into a single whole. All parts (elements) of the system are in certain relationships or connections with each other. Here we come to the next most important concept of systemology - the concept of structure.

Structure is the order of connections between elements of a system.

You can also say this: structure is the internal organization of the system. From the same bricks and other parts, in addition to a residential building, you can build a garage, a fence, a tower. All these structures are built from the same elements, but have different designs in accordance with the purpose of the structure. Using the language of systemology, we can say that they differ in structure.

Who among you has not been interested in children's construction kits: construction, electrical, radio engineering and others? All children's construction sets are designed according to the same principle: there are many standard parts from which various products can be assembled. These products differ in the order in which the parts are connected, i.e., in their structure.

From all that has been said, we can conclude: every system has a certain elemental composition and structure. The properties of the system depend on both the composition and structure. Even with the same composition, systems with different structures have different properties and may have different purposes.

— integrity. Violation of the elemental composition or structure leads to partial or complete loss of the system's feasibility.

You have and still have to encounter the dependence of the properties of various systems on their structure in various school disciplines. For example, it is known that graphite and diamond are composed of molecules of the same chemical substance - carbon. But in diamond, carbon molecules form a crystalline structure, while graphite has a completely different structure - layered. As a result, diamond is the hardest substance in nature, while graphite is soft and is used to make pencil leads.

Let's consider an example of a social system. Social systems are called various associations (collectives) of people: a family, a production team, a school team, a brigade, a military unit, etc. Connections in such systems are relationships between people, for example, relationships of subordination. Many such connections form the structure of a social system.

Here's a simple example. There are two construction teams, each consisting of seven people. The first brigade has one foreman, two deputies and two workers subordinate to each deputy. The second team has one foreman and six workers who report directly to the foreman.

The figures schematically represent the subordination structures in these two brigades:

Thus, these two teams are an example of two production (social) systems with the same composition (7 people each), but with different subordination structures.

The difference in structure will inevitably affect the efficiency of the teams and their productivity. With a small number of people, the second structure is more effective. But if there are 20 or 30 people in a team, then it is difficult for one foreman to manage the work of such a team. In this case, it is reasonable to introduce deputy positions, i.e., use the first subordination structure.

Systemic effect

Essence system effect: every system is characterized by new qualities that are not inherent in its constituent parts.

The same property is expressed by the phrase: the whole is greater than the sum of its parts. For example, individual parts of a bicycle: frame, handlebars, wheels, pedals, seat do not have the ability to ride. But these parts were connected in a certain way, creating a system called a “bicycle”, which acquired a new quality - the ability to ride, that is, the ability to serve as a vehicle. The same thing can be shown with the example of an airplane: no single part of the airplane has the ability to fly; but the aircraft (system) assembled from them is a flying device. Another example: the social system is a construction team. One worker with one specialty (bricklayer, welder, carpenter, crane operator, etc.) cannot build a multi-story building, but the whole team copes with this work together.

About systems and subsystems

As another example of a system, consider an object—a personal computer (PC). The figure shows a diagram of the composition and structure of PC.

The most superficial description of a PC is this: it is a system, the elements of which are the system unit, keyboard, monitor, printer, mouse. Can we call them simple elements? Of course not. Each of these parts is also a system consisting of many interconnected elements. For example, the system unit includes: a central processor, RAM, hard and floppy disk drives, CD-ROMs, external device controllers, etc. In turn, each of these devices is a complex system. For example, a central processor consists of an arithmetic-logical unit, a control unit, and registers. We can continue this way, going deeper and deeper into the details of the computer structure.

A system that is part of some other, larger system is called subsystem.

From this definition it follows that the system unit is a subsystem of a personal computer, and the processor is a subsystem of the system unit.

Is it possible to say that some simple computer part, for example a nut, is not a system? It all depends on the point of view. In a computer, a nut is a simple part because it cannot be disassembled into smaller parts. But from the point of view of the structure of the substance from which the nut is made, this is not so. A metal is made up of molecules that form a crystalline structure, molecules are made up of atoms, and atoms are made up of a nucleus and electrons. The deeper science penetrates into matter, the more it becomes convinced that there are no absolutely simple objects. Even the particles of an atom that are called elementary, such as electrons, also turned out to be difficult.

Any real object is infinitely complex. The description of its composition and structure is always of a model nature, that is, it is approximate. The degree of detail of such a description depends on its purpose. The same part of the system in some cases can be considered as its simple element, in other cases - as a subsystem with its own composition and structure.

Basic meaning research work A scientist’s work most often consists of searching for a system in the subject of his research.

The task of any science is to find systemic patterns in the objects and processes that it studies.

In the 16th century, Nicolaus Copernicus described the structure of the solar system. The Earth and other planets revolve around the Sun; they are connected into a single whole by the forces of attraction.
Systematization of knowledge is very important for biology. In the 18th century, Swedish scientist Carl Linnaeus wrote a book called Systems of Nature. He made the first successful attempt to classify all known species of animals and plants, and most importantly, he showed the relationship, that is, the dependence of some species on others. All Live nature appeared
as one big system. But it, in turn, consists of a plant system, an animal system, i.e. subsystems. And among the animals there are birds, beasts, insects, etc. All these are also systems.

Russian scientist Vladimir Ivanovich Vernadsky in the 20s of the 20th century created the doctrine of the biosphere. By biosphere he understood a system that includes all plant and animal world The Earth, humanity, as well as their habitat: the atmosphere, the surface of the Earth, the oceans, the subsoil developed by man (all this is called the active shell of the Earth). All subsystems of the biosphere are interconnected and dependent on each other. Vernadsky came up with the idea that the state of the biosphere depends on cosmic processes, in other words, the biosphere is a subsystem of larger cosmic systems.

, take a systematic approach to any work.

The essence of the systems approach: it is necessary to take into account all the significant systemic connections of the object with which you are working.

A very “sensitive” example for all of us of the need for a systematic approach is the work of a doctor. When undertaking to treat some disease, some organ, the doctor must not forget about the relationship of this organ with the entire human body, so that it does not turn out, as in the saying, “we treat one thing, cripple another.” The human body is a very complex system, so great knowledge and caution are required from the doctor.

Another example is ecology. The word “ecology” comes from the Greek words “ekoe” - “house” and “logos” - “study”. This science teaches people to treat the nature around them as own home. The most important task of ecology today is to protect nature from the destructive consequences human activity(use of natural resources, industrial waste emissions, etc.). Over time, people are increasingly interfering with natural processes. Some interventions are harmless, but there are others that can lead to disaster. Ecology uses the concept of “ecological system”. This is a person with the “fruits” of his activities (cities, transport, factories, etc.) and natural nature. Ideally, there should be a dynamic balance in this system, i.e. the destruction that man inevitably produces in nature should have time to be compensated by natural processes or by man himself. For example, people, cars, factories burn oxygen, and plants release it. For balance it is necessary to stand out
oxygen is no less than it is burned. And if the balance is upset, then eventually a catastrophe will occur on the scale of the Earth.

In the 20th century, an environmental disaster occurred with the Aral Sea in Central Asia. People thoughtlessly took water from the Amu Darya and Syr Darya rivers that fed it to irrigate their fields. The amount of evaporating water exceeded the influx, and the sea began to dry up. Now it has practically died and life on its former shores has become impossible for people, animals and plants. Here is an example of the lack of a systematic approach. The activities of such “transformers of nature” are very dangerous. Recently, the concept of “environmental literacy” has emerged. When interfering with nature, you cannot be a narrow specialist: only an oil worker, only a chemist, etc.

· page 32 No. 9, 10

V. Lesson summary (2 min.)

VI. Homework(3 min.)

§5; page 32 No. 4-8.

View document contents
"Lesson No. 9"

Subject: What is the system?

Lesson type: lesson on introducing new material

Goals:

To introduce students to the concepts: system, systemology, structure, subsystem, systems approach;

Consider the system effect, systems and subsystems, systems in science and systems approach;

Formation of general ideas of the modern scientific picture of the world;

formation of communicative qualities of a developing personality.

Equipment:

Interactive board;

MS PowerPoint

During the classes:

I .Organizational moment (2 min.)

Greetings. Post a new topic.

II . Updating knowledge (3 min.)

Checking homework.

III . Theoretical part (30 min.)

Systemology is the science of systems. What is the content of this science and what relation does it have to computer science, you will learn from this chapter.

System concept

Let us formulate the definition of the main concept of systemology - the concept of a system:

A system is a complex object consisting of interconnected parts (elements) and existing as a single whole. Any system has a specific purpose (function, purpose).

Here's another example: a bunch of bicycle parts and a bicycle assembled from them. A bicycle is system . Its purpose is to be a vehicle for humans.

The first main property of the system - expediency. This is the purpose of the system, the main function it performs.

System structure

Structure is the order of connections between the elements of the system.

You can also say this: structure - This is the internal organization of the system. From the same bricks and other parts, in addition to a residential building, you can build a garage, a fence, a tower. All these structures are built from the same elements, but have different designs in accordance with the purpose of the structure. Using the language of systemology, we can say that they differ in structure.

Who among you has not been interested in children's construction kits: construction, electrical, radio engineering and others? All children's construction sets are designed according to the same principle: there is a bunch of standard parts from which various products can be assembled. These products differ in the order in which the parts are connected, i.e., in their structure.

The second main property of the system - integrity. Violation of the elemental composition or structure leads to partial or complete loss of the system's feasibility.

You have and still have to encounter the dependence of the properties of various systems on their structure in various school disciplines. For example, it is known that graphite and diamond are composed of molecules of the same chemical substance - carbon. But in diamond, carbon molecules form a crystalline structure, and in graphite structure completely different - layered. As a result, diamond is the hardest substance in nature, while graphite is soft and is used to make pencil leads.

Let's consider an example of a social system. Social systems are various associations (collectives) of people: a family, a production team, a school team, a brigade, a military unit, etc. Connections in such systems are relationship between people, for example relationship subordination. Many such connections form the structure of a social system.

The figures schematically represent the subordination structures in these two brigades:

Thus, these two teams are an example of two production (social) systems with the same composition (7 people each), but with a different subordination structure.

The difference in structure will inevitably affect the efficiency of the teams and their productivity. With a small number of people, the second one is more effective structure . But if there are 20 or 30 people in a team, then it is difficult for one foreman to manage the work of such a team. In this case, it is reasonable to introduce deputy positions, i.e., use the first subordination structure.

Systemic effect

Essence system effect : every system is characterized by new qualities that are not inherent in its constituent parts.

The same property is expressed by the phrase: the whole is greater than the sum of its parts. For example, individual parts of a bicycle: frame, handlebars, wheels, pedals, seat do not have the ability to ride. But these parts were connected in a certain way, creating a system called “bicycle”, which acquired a new quality - the ability to ride, that is, the ability to serve as a vehicle. The same thing can be shown with the example of an airplane: no single part of the airplane has the ability to fly; but the airplane assembled from them ( system ) - a flying device. Another example: social system - construction team. One worker with one specialty (bricklayer, welder, carpenter, crane operator, etc.) cannot build a multi-story building, but the whole team copes with this work together.

About systems and subsystems

As another example of a system, consider the object - Personal Computer (PC). The figure shows a diagram of the composition and structure of PC.

The most superficial description of a PC is this: it is system , the elements of which are system unit, keyboard, monitor, printer, mouse. Can we call them simple elements? Of course not. Each of these parts is also system, consisting of many interconnected elements. For example, the system unit includes: central processor, RAM, hard and floppy disk drives, CD-ROM external device controllers, etc. In turn, each of these devices is complex system. For example, the central processor consists of an arithmetic-logical device, a control device, and registers. We can continue this way, going deeper and deeper into the details of the computer structure.

subsystem.

From this definition it follows that system unit is a subsystem of a personal computer, and CPU - subsystem of the system unit.

Is it possible to say that some simple computer part, for example a nut, is not a system? It all depends on the point of view. In a computer device, a nut is a simple part, since it cannot be disassembled into smaller parts. But from the point of view of the structure of the substance from which the nut is made, this is not so. A metal is made up of molecules that form a crystalline structure, molecules are made up of atoms, and atoms are made up of a nucleus and electrons. The deeper science penetrates into matter, the more it becomes convinced that there are no absolutely simple objects. Even the particles of an atom that are called elementary, such as electrons, also turned out to be difficult.

Any real object is infinitely complex. The description of its composition and structure is always of a model nature, that is, it is approximate. The degree of detail of such a description depends on its purpose. The same part of the system in some cases can be considered as its simple element, in other cases - as subsystem , having its own composition and structure.

About systems in science and systems approach

The main point of a scientist’s research work most often is to search for a system in the subject of his research.

The task of any science is to find systemic patterns in the objects and processes that it studies.

In the 16th century, Nicolaus Copernicus described the structure of the solar system. The Earth and other planets revolve around the Sun; they are connected into a single whole by the forces of attraction.
Systematization of knowledge is very important for biology. In the 18th century, Swedish scientist Carl Linnaeus wrote a book called Systems of Nature. He made the first successful attempt to classify all known species of animals and plants, and most importantly, he showed the relationship, that is, the dependence of some species on others. All living nature appeared
like one big system. But it, in turn, consists of a plant system, an animal system, i.e. subsystems. And among the animals there are birds, beasts, insects, etc. All these are also systems.

Russian scientist Vladimir Ivanovich Vernadsky in the 20s of the 20th century created the doctrine of the biosphere. By biosphere he understood a system that includes the entire flora and fauna of the Earth, humanity, as well as their habitat: the atmosphere, the surface of the Earth, the oceans, the subsoil developed by man (all this is called the active shell of the Earth). All subsystems of the biosphere are interconnected and dependent on each other. Vernadsky came up with the idea that the state of the biosphere depends on cosmic processes, in other words, the biosphere is a subsystem of larger cosmic systems.

If a person wants to be a good specialist in his field, he must have systems thinking , take a systematic approach to any work.

The essence of the systems approach : it is necessary to take into account all the significant systemic connections of the object with which you are working.

A very “sensitive” example for all of us of the need for a systematic approach is the work of a doctor. When undertaking to treat some disease, some organ, the doctor must not forget about the relationship of this organ with the entire human body, so that it does not turn out, as in the saying, “we treat one thing, cripple another.” The human body is very complex system , so the doctor is required to knowledge and caution.

Another example is ecology. The word “ecology” comes from the Greek words “ekoe” - “house” and “logos” - “teaching”. This science teaches people to treat the nature around them as their own home. The most important task of ecology today has become the protection of nature from the destructive consequences of human activity (use of natural resources, emissions of industrial waste, etc.). Over time, people are increasingly interfering with natural processes. Some interventions are harmless, but there are others that can lead to disaster. Ecology uses the concept of “ecological system " This is a person with the “fruits” of his activities (cities, transport, factories, etc.) and natural nature. Ideally, there should be a dynamic balance in this system, i.e. the destruction that man inevitably produces in nature should have time to be compensated by natural processes or by man himself. For example, people, cars, factories burn oxygen, and plants release it. For balance it is necessary to stand out
oxygen is no less than it is burned. And if the balance is upset, then eventually a catastrophe will occur on the scale of the Earth.

When studying or transforming nature, one must see it as a system and make efforts not to disturb its balance.

IV . Consolidation of knowledge (5 min.)

p. 32 No. 9, 10

V . Lesson summary (2 min.)

Class work is assessed and grades are called.

VI . Homework (3 min.)

§5; page 32 No. 4-8.

View presentation content
“What is a system. Grade 10"

Systemology - systems science.

Examples

Brick house -

complex object

Brick -

simple object

Example

Automobile -

complex object

Automotive parts –

simple objects

The main concept of systemology is the concept of a system.

System is a complex object consisting of interconnected parts (elements) and existing as a single whole.

Every system has a specific purpose (function, goal)

Brick house.

Purpose – you can live in it

Pile of bricks

There is no unity

no expediency

Examples of systems and their elements

Bike -

complex object (system)

Bicycle parts –

simple objects

(system elements)

The first main property of the system – expediency (this is the purpose of the system, the main function that it performs).

Purpose of the bicycle –

be transport

remedy for humans.

Purpose of the house –

you can live in it.

System structure

The second most important concept of systemology is structure.

Structure is the order of connections between the elements of the system.

Structure is the internal organization of a system

You can build a garage, fence, tower from bricks

They have different designs

in accordance with the purpose of the structure, i.e. they differ in structure

Example

The children's designer
Various designs can be assembled from the same parts

Conclusion:

Every system has a certain elemental composition and structure.
The properties of the system depend on both the composition and structure.
Even with the same composition, systems with different structures have different properties and may have different purposes.

The second main property of the system – integrity. Violation of the elemental composition or structure leads to partial or complete loss of the feasibility of the system

Dependence of the properties of various systems on their structure

Molecule

carbon

Layered structure of graphite

Crystal structure of diamond

Example of a social system

Social systems are various associations (collectives) of people: a family, a production team, a school team, a brigade, a military unit, etc.

Connections in such systems are relationships between people, for example, relationships of subordination. Many such connections form the structure of a social system.

Structures

subordination

in two brigades

Systemic effect

The essence of the system effect:

The same property is expressed by the phrase: the whole is greater than the sum of its parts

Bike -

Movement device

Systemic effect

The essence of the system effect: Every new system is characterized by new qualities that are not inherent in its constituent parts.

Airplane -

flying device

Systems and subsystems

Composition and structure of a personal computer

External controllers

devices

NMJD

NGMD

System unit

Monitor

Information Highway

Printer

CPU

RAM

Mouse

Keyboard

Registers

Systems and subsystems

A system that is part of some other, larger system is called subsystem.

Examples of systems and their elements

In device

computer

From point of view

structure of matter

Simple detail

Subsystem

Conclusion:

About systems in science and systems approach

The main meaning of the research work

scientist most often consists of searching

systems in the subject of research.

The task of any science – find systemic patterns in the objects and processes that she studies.

Nicolaus Copernicus in XVI century described

structure of the solar system

Carl Linnaeus wrote the book "System of Nature"

C. Linnaeus made the first successful attempt to classify all known

species of animals and plants and showed the dependence of some species on others.

Russian scientist V.I. Vernadsky in the 20s XX centuries created the doctrine of the biosphere.

Under biosphere he understood system , which includes the entire flora and fauna of the Earth, humanity, as well as their habitat: the atmosphere, the surface of the Earth, the world ocean, and the subsoil developed by man.

If a person wants to be a good specialist in his field, he must have systems thinking and take a systematic approach to any work.

The essence of the systems approach: it is necessary to take into account all the essential systemic connections of the object with which you are working.

An example of the need for a systematic approach

Doctor's work.
When treating any organ, it is necessary to take into account the relationship of this organ with the entire body.

An example of the lack of a systematic approach

Ecological disaster with the Aral Sea
The sea began to dry up due to the withdrawal of water from the Syr Darya and Amu Darya.

The activities of such “transformers of nature” are very dangerous. Recently, the concept of “environmental literacy” has emerged. When interfering with nature, you cannot be a narrow specialist: only an oil worker, only a chemist, etc.

Conclusion:

When studying or transforming nature, one must see it as a system and make efforts not to disturb its balance.

Homework

§ 5;
Questions 1 – 8 on page 32

Classification called distribution some set of objects into classes according to the most significant features.

Sign or their totality, by which objects are combined into classes, are basis classifications.

Class- This collection of objects, having some characteristics community.

Systems are divided into classes according to various characteristics and depending on the decision tasks can be selected different principles classifications.

The interaction of different classes of systems is extremely complex and requires special research. Each class of systems is divided into various subclasses, located in a certain hierarchy to each other.

Classifications are always relative. Any goal system classifications – limit the choice of approaches to display the system, compare the techniques and methods of CA to the selected classes, give recommendations on the choice of methods for the corresponding class of systems. At the same time, the system can be simultaneously characterized by several signs, which allows her to find a place at the same time in different classifications.

This can be useful when choosing methods for modeling systems. Below is a classification of systems according to the following classification criteria.

1. By nature system elements are divided into real (material) And abstract.

Real(physical) systems are objects consisting of material elements. We are able to perceive real systems– these are mechanical, electrical, electronic, biological, social and other subclasses of systems and their combinations.

Abstract(ideal) systems consist of elements having no direct analogues in the real world. There are such systems product of human thinking, i.e. they are formed as a result creative activity person.

Example: hypotheses, various theories, plans, ideas, systems of equations.

However, abstract systems, like real ones, have a significant impact on our reality.

Example: a system of knowledge, without which reality is impossible. Abstract knowledge before our eyes can turn into real object(we produce PCs, build houses). A real system can become an abstraction(they burned the letter - and it remained in our memories). Abstractions are information, vacuum, energy.

The importance of abstract systems cannot be overestimated.

2. Depending on the origin, natural(natural) and and artificial systems (but these are all material)

Natural systems – set of natural objects (solar system, living organism, soil, climate, wind, current, etc.) arose without human intervention. It is believed that the emergence of a new natural system is very rare.

Artificial systems- This a set of socio-economic or technical objects. Arose as a result human creativity, their number increases over time.

Artificial systems differ from natural the presence of certain operational goals(i.e. purpose) and availability of management.

Examples: residential buildings, sports complexes, etc.

3. By duration of existence systems are divided into permanent and temporary.

From the point of view of dialectics All existing systems temporary.

Permanent- This all natural systems, as well as artificial ones, which retain their essential properties, determined by the purpose of these systems, during a given period of operation.

4. According to the degree of connection with the external environment systems are divided into closed (closed) and open.

The system is closed if she has no environment, i.e. external systems in contact with it.

TO closed These also include those systems that are not significantly influenced by external systems. Closed systems don't exchange With environment matter, but exchange energy. An example of a closed system is a clock mechanism, a local network for processing confidential information, space objects “black holes”, subsistence farming.

Closed systems should not, strictly speaking, have not only an input, but also an output. All reactions of such systems are unambiguously explained by changes in their states.

Open a system is called if there are other systems associated with it that influence it and which it also influences. Those. an open system is characterized by interaction with the external environment. Such a system exchanges energy and matter (mass) and information with the environment.

The distinction between closed and open systems is an important point in General Systems Theory because any attempt to consider open systems as closed, when the external environment is not taken into account, is fraught with great danger, even catastrophic, and this danger must be fully realized. Example: drying up of the Aral Sea, the ecological situation around the island. Baikal, the appearance of ozone holes.

Closed systems practically does not exist in nature. All living systems - open systems. Nonliving systems are relatively closed.

Concept openness of systems is specified in each subject area.

So, in fields of computer science open information systems are software and hardware systems that have the following properties:

a) compatibility, i.e. the ability to interact with other complexes based on developed interfaces for exchanging data with applied tasks in other systems;

b) portability (mobility) – software m.b. easily ported to various hardware platforms and operating environments;

c) capacity building is the inclusion of new software and hardware not provided for in the initial version;

5. By the nature of behavior systems are divided into systems with and without control.

With control– these are systems in which the process of goal setting and goal implementation is realized (usually these are artificial systems).

No control– this is, for example, the solar system, where the trajectory of the planets is determined by the laws of mechanics.

6. According to the possession of biological functions- on alive And non-living systems.

The living have biological functions(birth, death, reproduction). Sometimes the concepts of “birth” and “death” are associated with non-living systems when describing processes that seem to be similar to life, but do not characterize life in its biological sense (there is the concept of the life cycle of a system).

All abstract systems(science physics, ideas) are non-living, A real systems(cells, animals, humans, plants) can be living and non-living (PC, EIS - they have a life cycle).

7. Depending on the degree of variability of properties systems are divided into static(when studying them, changes over time in the characteristics of their essential properties can be neglected) and dynamic (dividing them into discrete and continuous is associated with the choice of mathematical modeling apparatus).

Static are systems with one condition (crystals).

Dynamic– have many possible states, which can vary as continuously(for analysis, the theory of ordinary differential equations and partial differential equations (switching speed in a car) is usually used), and discretely. Example: any technical device (computer, bus, etc.) can work, be repaired, undergo maintenance, i.e. have different states. To analyze such systems, mathematical models such as Markov chains, queuing systems, and Petri nets are used.

8. Depending on the degree of human participation in the implementation of control actions, systems are divided into technical (organizational - economic - they function without human participation, for example, systems automatic control- self-propelled guns) , man-machine(ergatic - they function with human participation, that is, a person is associated with technical devices, but the final decision is made by the decision maker, while automation tools help him justify the correctness of this decision, for example, automated control systems, electronic information systems) , organizational(these are social systems, for example, society as a whole, groups, collectives of people).

9. Depending on the degree difficulties all systems are divided into simple, complex And big. This division emphasizes that the SA considers not any, but precisely complex systems large scale. Although the concept of “large” is not always associated specifically with the size of the system. There is still no generally accepted boundary separating simple, large and complex systems.

With this division they usually distinguish structural, functional(computational) complexity and the presence of different by type of connections between system elements.

By this sign distinguish complex systems from large systems, which represent the totality homogeneous elements combined connection of only one type.

They are divided into artificial and natural (natural) complex systems.

Simple systems can be described with sufficient complexity and accuracy by known mathematical relationships. Their features are, What every property(temperature, pressure) of such systems can be studied separately under the conditions of a classic laboratory experiment, and then describe methods of traditional technical disciplines(radio engineering, electronics, applied mechanics - properties: dependence of gas pressure on temperature, resistance on capacitance, etc.)

Examples of simple systems: elements electronic circuits, electrical, individual parts.

Complex systems consist of big numbers interconnected And interacting elements, each of which can be represented as a system(subsystems).

Complex systems are characterized the diversity of the nature of the elements, connections between them, heterogeneity of structure(this concept will be given in detail below) and multidimensionality, i.e. a large number composed elements.

Complex systems have the following properties:

1) property robustness, i.e. ability to preserve partial performance (efficiency) upon failure individual elements or subsystems;

2) property emergence (integrity, integrativeness), which is absent from any of its constituent parts (as already mentioned). Those. separate consideration of each element does not provide a complete picture of a complex system generally. Emergence can be achieved due to feedback, playing a huge (critical) role in managing a complex system.

It is believed that structural complexity the system must be proportional volume of information, necessary for its description (to remove uncertainty).

TO complex system can be attributed system,possessing, at least, one of the listed signs:

1) the system can be smash into subsystems and study each of them separately;

2) the system is functioning in conditions significant uncertainty and the impact of the environment on it, determines the random nature of changes in its indicators;

3) the system makes a purposeful choice of its behavior.

Examples of complex systems: living organisms (humans), PC, ACS, EIS.

Large systems (not by dimensions) – this is complex spatiotemporal systems in which subsystems (and their components) are classified as complex.

Additional features that characterize a large complex system:

1) large sizes (not in size, but in the number of elements);

2) complex hierarchical structure;

3) circulation in the system of large information, energy and material flows;

4) high level of uncertainty in the description of the system.

Examples of large complex systems: communication systems, automated control systems, industries, business systems, military units.

BUT! Large systems may not always be complex (example: pipeline, gas pipeline, consisting of a large number of individual links - pipes) (only one type of connection).

Complex systems will not always be large in size (for example, PC, microprocessor).

Complex systems are characterized by the processes (functions) they perform, their structure, and their behavior over time.

Our compatriot mathematician G.N. Cooks divides all systems depending on the number of elements included in them into 4 groups:

1) small systems (10 – 10 3 elements);

2) complex systems (10 3 – 10 7 elements) - automatic telephone exchange, transport system big city;

3) ultra-complex systems (10 7 – 10 30 elements) - organisms of higher animals and humans, social organizations;

4) supersystems (10 30 – 10 200 elements) - stellar universe.

10. By type of scientific direction, used for modeling, systems are divided into mathematical, chemical, physical, etc.

The most complex system today is the human brain.

11. Focused, goal-oriented systems– i.e. directed to achieve the goal.

It is not always possible to apply the concept when studying systems target. But when studying economic, organizational objects important select class targeted or purposeful systems (this concept includes the ability of a system to pursue the same goal, changing its behavior when external conditions change, that is, the ability to show adaptability while maintaining a goal, for example, cruise missiles fly very low, repeating the surface topography).

This class includes systems in which goals are set externally(usually this occurs in closed (technical) systems) and systems in whose goals are formed within the system(typical for open self-organizing systems). For such systems, techniques have been developed to help form and analyze the structure of goals.

There is such a thing as goal formation patterns.

12. By degree of organization systems are divided into well-organized, poorly organized (or diffuse) and self-organized.

The difference between this classification and others is that in it the classes can be quite clearly distinguished using characteristics characteristic of each class, which make it possible to assign different classes of MPPS and ways of presenting goals in them.

These selected classes should practically be considered as approaches to displaying an object or problem being solved, which can be selected depending on the stage of cognition of the object and the possibility of obtaining information about it.

Thus, having determined the class of the system, we can give recommendations on the choice method that allows you to more adequately display it.

Well organized systems(HOS)

– these are systems in which the researcher manages to determine all the elements of the system and their relationships with each other and with the goals of the system in the form of deterministic(analytical, graphical) dependencies.

Most models of physical processes and technical systems are based on the representation of systems by this class. Although for complex objects the formation of such models significantly depends on the decision maker (for example, an atom can be represented in the form of a planetary model consisting of a nucleus and electrons, which simplifies the real picture, but is sufficient for understanding the principles of interaction of the elements of this system).

The operation of a complex mechanism can be represented by a simplified diagram or system of equations.

HOS Feature:

A problem situation can be described in the form of expressions connecting the goal with the means, that is, in the form of a functioning criterion, a target function, which can be presented in the form of an equation, formula, system of equations or complex mathematical models, including equations, inequalities, etc. .P.

Representation of an object in the form of an XOS is used in cases where it can be represented deterministic description and adequacy has been experimentally proven model of a real object or process.

It is not recommended to use the HOS class to represent complex multi-component objects or multi-criteria problems solved when developing technical complexes or improving the management of enterprises and organizations, since in this case requires unacceptably high costs time to form a model and impossible to prove adequacy of the model.

Therefore, when presenting complex objects, problems, especially in socio-economic systems, on in the initial stages of the study they are displayed as a class POS(diffuse) and self-organizing systems

Poorly Organized System (diffuse)

– when representing an object in the form of this system not placed the task is to determine all taken into account elements (components) and their connection with the goals of the system. In this case, based on selective studies obtain characteristics or patterns ( statistical, economic, etc.) and spread these patterns on system behavior generally. There are some caveats to this. For example, when statistical regularities are obtained, they are extended to the behavior of the system with a certain probability, which is assessed using the techniques of mathematical statistics (using criteria and hypothesis testing).

Example of a diffuse system: gas. Its properties are not determined by accurately describing the behavior of each molecule, but characterize the gas by macroparameters (pressure, permeability, etc.). Based on these parameters, devices are developed that use these properties, but the behavior of each individual molecule is not studied.

Displaying objects in the form of diffuse systems is widely used in determining the number of staff in service institutions (repair teams, workshops), in determining throughput (gas stations, ticket offices, telegraph stations, railways, airport) systems of various kinds (usually queuing theory methods are used in these problems), in the study of documentary information flows.

Self-organizing (or developing) systems (economic).

They have subclasses:

Self-regulating;

Self-learning;

Self-adjusting.

Displaying objects as self-organizing systems allows you to explore least studied objects, processes with large uncertainty on initial stage of problem formulation.

This class of systems is characterized by a number of features that bring them closer to real developing objects (economic and social). They also have features characteristic of diffuse systems: random behavior and unpredictability, instability of individual parameters, the ability to adapt to changing environmental conditions; change the structure maintaining integrity properties; formulate possible behavior options and choose the best one. At the same time, all this causes uncertainty and makes management difficult. Models of such systems should make it possible to display their properties discussed above. But when forming such models the usual idea is changing about models, typical for mathematical modeling, for applied mathematics. The view changes and about proof adequacy of such models (the adequacy of a model is understood as its compliance with the modeled object or process).

Main Feature this class of systems - fundamental limitations of their formalized description. This feature leads to the need to combine formalized methods(MFPS) and methods of qualitative analysis(MAIS) and forms the basis for most SA models and techniques.

Main constructive idea modeling when displaying an object by a class self-organizing systems next:

a) is being developed at the initial stage sign system, with the help of which currently known elements, components of the system and their connections are recorded;

b) as knowledge about an object or process accumulates, with the help of decomposition and structuring rules, new, previously unknown relationships and dependencies are obtained, which either suggest the next steps towards preparing a solution, or serve as the basis for decisions made;

c) as the ideas about the object, the problem situation in the system model are clarified, a gradual transition can be made from the methods of discrete mathematics (set-theoretic, logical, linguistic, semiotic, graphical methods) to more formalized methods - statistical, analytical.

But for the class of self-organizing (developing) systems, knowledge of only MFPS methods is not enough. At different stages of modeling, MAIS methods can help (brainstorming method, scenario tree, goals, decision tree, Delphi, expert methods, etc.).

This class of systems owes its name to the fact that the system seems to include a “mechanism” for gradual refinement, “development” of the system model.

13. By type of displayed object systems are divided into technical, biological, uh economic, organizational, social etc.

14. From a decision-making perspective systems are divided into technical, biological, social.

1. Technical system includes equipment, machines, computers and other functional products that have instructions for the user. The method for calculating mast supports for power lines, solving a problem in mathematics, the procedure for turning on a computer and working with it - such solutions are formalized nature and are performed in a strictly defined order. Those. set of solutions in technical system limited and the consequences of decisions are usually predetermined. The quality of the decision made and implemented depends on the professionalism of the decision maker.

2. Biological system includes the flora and fauna of the planet, including relatively closed biological subsystems: the human body, anthill, termite mound, etc. This system has a greater variety of functioning than the technical one.

The range of solutions in this system is also limited due to the slow evolutionary development of the animal and plant world. BUT, consequences of decisions in bio logical systems ah often turn out to be unpredictable: an agronomist’s decision to use certain chemicals as fertilizers, a doctor’s decision related to the diagnosis of new diseases in patients, a decision to use freon gas in cylinders with a spray, a decision to flush industrial waste into the river...

In these systems, it is necessary to develop several alternative solutions and select the best one based on some criteria. The decision maker must correctly answer the question “What will happen if...”

Quality decision taken depends on the professionalism of the decision maker, which determines the ability to find reliable information, use appropriate decision methods and choose the best from alternatives.

3. Social (public) system characterized by the presence of a person in a set of interrelated elements: family, production team, driver driving a car; informal organization, even 1 person (by himself).

In terms of the variety of problems that arise, these systems are significantly ahead of biological ones.

The set of solutions in a social system is characterized by great diversity in the means and methods of implementation.

A social system may include biological and technical, and biological – technical.

Airplane is a heavier-than-air aircraft with an aerodynamic flight principle. An airplane is a complex dynamic system with a developed hierarchical structure, consisting of elements interconnected by purpose, location and functioning; in it one can distinguish subsystems for creating lifting and driving forces, ensuring stability and controllability, life support, ensuring the fulfillment of the target function, etc.

computer network– a complex system that consists of computers and a data transmission network (communication network). The main purpose of computer networks is to ensure the interaction of remote users based on data exchange over the network and the sharing of network resources (computers, application programs and peripheral devices).

If an object has all the characteristics of a system, then it is said to be systemic . The given examples of systems illustrate the presence of such systematic factors as:

· integrity and possibility of decomposition into elements(in a computer network these are computers, communications equipment, etc.);

· presence of stable connections(relationships) between elements;

· orderliness(organization) elements into a specific structure;

· providing elements with parameters;

· presence of integrative properties, which are not possessed by any of the elements of the system;

· the presence of many laws, rules and operations with the above system attributes;

· the presence of a goal of functioning and development.

Systems are divided into classes according to various criteria, and depending on the problem being solved, different classification principles can be chosen. A characteristic or a combination of them, by which objects are combined into classes, is the basis of classification. Class- this is a collection of objects that have certain characteristics of commonality.

There are quite a lot of classifications of systems in science. For example, one of them provides for the division of systems into two types - abstract And material.

Material systems are real-time objects. Among all the diversity of material systems, there are natural And artificial systems.

Natural systems represent a collection of natural objects and are divided into astrocosmic and planetary, physical and chemical.

Artificial systems is a set of socio-economic or technical objects. They can be classified according to several criteria, the main one of which is the role of a person in the system. Based on this feature, two classes of systems can be distinguished: technical and organizational-economic systems.

Abstract systems is a speculative representation of images or models of material systems, which are divided into descriptive (logical) and symbolic (mathematical).

Descriptive systems is the result of a deductive or inductive representation of material systems. They can be considered as systems of concepts and definitions (a set of ideas) about the structure, about the basic laws of states and about the dynamics of material systems.

Symbolic systems represent a formalization of logical systems, they are divided into three classes:

static mathematical systems or models that can be considered as a description of the state of material systems using the mathematical apparatus (equations of state);

dynamic mathematical systems or models, which can be considered as a mathematical formalization of the processes of material (or abstract) systems;

quasi-static (quasi-dynamic) systems, located in an unstable position between statics and dynamics, which under some influences behave as static, and under other influences as dynamic.

Other types of classifications can be found in the scientific literature.

· by type of displayed object- technical, biological, social, etc.;

· by nature of behavior- deterministic, probabilistic, game;

· by type of determination- open and closed;

· by complexity of structure and behavior- simple and complex;

· by type of scientific direction used for their modeling - mathematical, physical, chemical, etc.;

· by degree of organization- well organized, poorly organized and self-organized.

Each system has certain properties associated with its functioning. The most common are the following:

· synergy- the maximum effect of the system is achieved only in the case of maximum efficiency of the joint functioning of its elements to achieve a common goal;

· emergence- the appearance of properties in the system that are not inherent in the elements of the system; the fundamental irreducibility of the properties of a system to the sum of the properties of its constituent components (non-additivity);

· focus- the presence of a system goal (goals) and the priority of the system’s goals over the goals of its elements;

· alternativeness- functioning and development (organization or self-organization);

· structure- it is possible to decompose the system into components and establish connections between them;

· hierarchy- each component of the system can be considered as a system; the system itself can also be considered as an element of some supersystem (supersystem);

· communication skills- the existence of a complex system of communications with the environment in the form of a hierarchy;

· adaptability- the desire for a state of stable equilibrium, which involves adapting the parameters of the system to the changing parameters of the external environment;

· integrativeness- presence of system-forming, system-preserving factors;

· equifinality- the ability of a system to achieve states independent of initial conditions and determined only by system parameters.

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