Let's consider the main stages of system analysis.

  • 1. Diagnosing the problem. Establishing the problem. The exact formulation of the problem. Analysis of the logical structure of the problem. Development of the problem in the past and in the future. External communication problems with other problems. Principal solvability of the problem.
  • 2. Definition of the system. Description of the system. Determining the position of the observer. Object definition. Selection of elements (determination of the boundaries of the partition of the system). Definition of subsystems. Definition of the environment.
  • 3. Analysis of the structure of the system. Determination of the levels of the hierarchy. Definition of language. Determination of management processes and information channels. Description of subsystems and their functional structure.
  • 4. Formulation of the general goal and criterion of the system. Determination of goals - the requirements of the supersystem. Define the goals and constraints of the environment. Formulation of a common goal. Determination of the criterion. Decomposition of goals and criteria by subsystems. Composition of the general criterion from the criteria of the subsystems.
  • 5. Decomposition of the goal, identifying the need for resources and processes. Formulation of top-rank goals. Formulation of goals for current processes. Formulation of performance goals. Formulation of development goals.
  • 6. Identification of resources and processes, composition of goals. Assessment of existing technology and capacities. Assessment of the current state of resources. Assessment of ongoing and planned projects. Assessment of the possibilities of interaction with other systems. Assessment of social factors. Composition of goals.
  • 7. Forecast and analysis of future conditions. Analysis of stable trends in the development of the system. Forecast of the development of changes in the environment. Predicting the emergence of new factors that have a strong impact on the development of the system. Analysis of the resources of the future. Comprehensive analysis of the interaction of factors of future development, analysis of possible shifts in goals and criteria
  • 8. Evaluation of goals and means. Calculation of scores by criterion. Assessing the interdependence of goals. Assessing the relative importance of goals. Assessment of scarcity and cost of resources.
  • 9. Selection of options. Analysis of goals for compatibility. Checking goals for completeness. Clipping redundant targets. Planning options for achieving individual goals. Evaluation and comparison of options. Combining a complex of interrelated options.
  • 10. Diagnosis of the existing system. Modeling the socio-economic process. Identification of shortcomings in the organization of production and management. Identification and analysis of measures to improve the structure and management of the organization.
  • 11. Building a comprehensive development program. Formulation of activities, projects and programs. Determination of the priority of goals and measures to achieve them. Distribution of spheres of activity. Distribution of areas of competence. Development of a comprehensive action plan within the limits of time resources. Distribution among responsible organizations, managers and executors.
  • 12. Designing an organization to achieve goals. Setting the goals of the organization. Formulation of the functions of the organization. Organizational structure design. Information technology design. Design of operating modes. Designing mechanisms for material and moral incentives.

Let's consider the implementation of the first stage of system analysis - problem diagnosis.

A problem is called a critical mismatch between the existing and desired (necessary) values ​​of the effect generated by the system.

After establishing the existence of the problem, the stage of its diagnosis begins.

Diagnostics of the problem is the analysis of the values ​​and relationships of the parameters of the organizational and production system and the external environment, in order to establish the causes of the problem. At the same time, the diagnostic stage assumes that the researcher knows the functional aggregate structure and values ​​of the parameters of the control object during its normal functioning.

Diagnosing a problem means answering the following questions:

What is really going on in the control system?

What are the reasons for this?

What is behind all this?

The first stage in diagnosing a complex problem is the awareness and identification of signs of abnormal behavior of the control system. Example: low margins, sales, production and quality, excessive costs, multiple conflicts in the organization, high staff turnover.

At the second stage of diagnosing the problem, the effects of the interaction of internal factors of the system and external factors of the environment are assessed. At the same time, internal factors mean the amount of equity capital, depreciation of fixed assets, organization structure, personnel qualifications, etc. External environmental factors are the level of taxes, the structure of demand, prices, etc.

The third stage of diagnostics is associated with making a decision to eliminate the problem. In this case, it is necessary to clearly define in which directions one should move, since a solution to the problem can exist in the area of ​​either changes in functions, or structure, or parameters of the work of the organizational and production system.

The problem is functional , if it manifests itself and, accordingly, can be solved at the level of functions of the organizational and production system.

For example, the solution to the problem is possible when switching to the release of a new product or service; when the market sector changes; when the position and nature of relationships with suppliers changes; when changing forms of ownership; when changing industry affiliation and other changes affecting the fundamentals of the work of the organizational and production system.

The problem is of a structural nature and can be solved by changing the structure of the organizational and production system, if its solution does not yet require a change in functions, but can no longer be achieved by changing the numerical values ​​of individual parameters. The need for structural changes may arise when a marketing strategy is changed, a new product similar to the one currently being produced is developed, and a new type of contractual relationship with existing partners is transitioned.

The problem is parametric if it can be eliminated by changing only the parameters of the organizational and production system.

The block diagram of the control and diagnosis of the problem is given in Appendix 1.

Thus, from the given detailed schemes of stages and procedures of system analysis, it is obvious that cognitive operations are widely used at all stages, i.e. operations associated with the knowledge of the subject area and control object and with the creation of their ideal model.

Due to the same variety of tasks solved by the methods of system analysis, and the wide scope of their application, there is no single list and sequence of research stages suitable for all cases. Depending on the class of problems to be solved, on the stage of research and the scope of their application, stages of research, different in content and sequence, are used.

But there is a certain list of stages of system analysis, the composition and sequence of application of which almost does not depend on the problem being solved. They are used more often than others at various stages of systems analysis.

Stage 1. Problem analysis: Tasks of the stage: correct and accurate formulation of the problem, analysis of the logical structure and development of the problem in time, determination of external relations of the problem and assessment of its fundamental solvability.

Stage 2. Definition of the system, analysis of its structure. Stage tasks: identifying the specifics of the task; determination of the positions of the observer and the object of research; highlighting system elements; determination of the boundaries of the decomposition of the system; definition of subsystems and the scope of their functioning.

In addition, depending on the type of system, the following tasks are solved: determining the level of the hierarchy (in large systems); definition and specification of control processes and information channels (in cybernetic systems), etc.

Arbitrariness in the allocation of subsystems and processes implemented in them dooms system research to failure. If in technical systems, the structure of subsystems is clearly visible, then in systems of economic management all structural relationships are very much hidden behind the relations of administrative subordination.

When solving the current problems of economic management, routine procedures overshadow the goals and processes of development. Identifying development goals and processes and separating them from routine ones require from the researcher not only the rigor of logical thinking, but also the ability to find the necessary contacts with management workers.

Stage 3. Formulation of the general goal and criterion of the system, where the tasks are: formulation of top-level goals; the formulation of the general goals of the system under study, linked to the goals of the higher-level system; determination of the system criterion; decomposition of goals into subsystems; formulation of criteria for subsystems and composition of the general criterion of the system from the criteria of subsystems; identifying resource requirements, etc.

In a systematic analysis, a number of social, political, ethical and other factors do not lend themselves to quantitative formalization, but they must be taken into account. To take these factors into account, they resort to subjective assessments of experts.

Stage 4. Identification of resources and processes, analysis of factors of future development, composition of goals... Stage objectives: assessment of existing technologies and capacities; assessment of the current state of resources; assessment of the possibilities of interaction with other systems in terms of providing resources; analysis of the resources of the future; a comprehensive analysis of the interaction of factors of future development.

Because system analysis deals with the development perspective, it is necessary to take into account possible changes in the perspective of technologies, capacities, possible discoveries and inventions, a possible transformation of goals and criteria.

Stage 5. Selection of goals and solutions, where the tasks are: analysis of goals for compatibility; checking targets for completeness and cutting off redundant targets; planning alternative options for achieving goals; evaluation and comparison of options according to the selected criteria; combination of complexes of interrelated options.

One of the central points of this stage is the analysis of goals for completeness (are all goals taken into account?) And truncation of goals - cutting off goals and goals of little importance that do not have the means to achieve those, as well as the selection of specific options for achieving an interconnected set of most important goals.

Problems solved by the methods of systems analysis most often arise not from scratch, but in real-life systems. In this regard, the task of systems analysis is not to create a new system or management body, but to improve the work of existing ones, to orient them towards solving a new problem. In these cases, there is a need for a diagnostic analysis of the elements of the system, aimed at identifying their capabilities, shortcomings, processing information and making decisions in order to eliminate these shortcomings and modernize the system.

6 stage. Choosing a solution method... The well-known methods of solving the problem are initially considered; if these methods turn out to be inadequate to the task at hand, then new methods of solution are sought or developed, or the task itself is revised.

Technological solutions all methods can be divided into 3 classes:

- standard: methods based on the use of standard or prescribed techniques and procedures; the basis of these methods is the procedural side of the process;

- analytical: solution methods based on the use of mathematical models; are used to solve a wide class of structured problems; however, the application of these methods is hampered by the impossibility of formalizing a number of factors influencing the solution of the problem; the presence of uncertainties in the conditions of the system's functioning; the presence of multi-criteria; the presence of a conflict of interests of persons participating in decision-making;



- imitation: methods based on artificial reproduction of the investigated processes with the use of a computer-human dialogue; it is used in cases when the problem under study cannot be completely solved by one method; the decision process is broken down into stages, the results of which are analyzed and corrected by a human, and launched as the initial plan for the next stage.

Depending on the principles of finding a solution methods are divided into 2 classes:

- methods of successive improvement of solutions: the problem is solved for an initial set of conditions; an analysis of the possibility of achieving an optimal solution is carried out; the factor is chosen that most hinders the development of the system, i.e. a problematic, critical place in the system is found, ways of solving this problem are found, then another critical place is selected, etc.; The disadvantage of the method is that the interdependencies of factors are not taken into account;

- methods of finding the ideal: Initially, the limiting (ideal) levels for each factor are considered, which provide the best version of the system, regardless of their feasibility, i.e. an ideal solution is being developed; then, for each factor, an achievable limit is set taking into account real possibilities, i.e. deviation from the ideal solution begins; the process continues until such a distribution of efforts is found in which deviation from the ideal is minimal or all reserves for improving this factor are expended.

The choice of the method is inextricably linked with the formulation of the problem and with the conditions for making decisions. When solving problems in terms of certainty classical optimization methods or mathematical programming methods can be used. When solving problems at risk- methods of probability theory and mathematical statistics; in the face of uncertainty- methods of game theory.

7 stage. Building a comprehensive development program... Stage objectives: formulation of activities, projects and programs; determining the priorities of goals and measures to achieve them; development of complex and planned measures for resources and time; distribution of activities among responsible organizations and performers.

The results of the previous stages of systems analysis, obtained within the framework of systemic and mathematical concepts, need to be translated into the language of technical, social, economic, etc. categories in which the studied system is considered. Then, complex programs are created to implement these decisions with distribution in time and responsible executors.

Stage 8. Decision-making: when analyzing semi-structured problems, the number of solutions may be unlimited, and it may turn out that all possible alternatives cannot be considered, and the optimal solution may turn out to be unattainable. In these cases, several equivalent alternatives are selected, among which the best possible solution is sought and quasi-optimal solutions are obtained, i.e. we come to some kind of compromise; the same situation arises in problems related to multicriteria and uncertainties of various kinds.

This completes the decision-making process and begins the process of their implementation, which is qualitatively different from the first in that in the first case the main subject of labor is information, in the second - material, energy and financial resources.

The stages considered are the most common and frequently used stages of systems analysis. The implementation of all stages in full is extremely difficult, therefore, in practice, some of the stages are used, the sequence of their application, the depth of analysis, the scope of tasks at each stage depend on the specific problem being solved, on the purpose of the study and the nature of the problem being investigated.

It must be borne in mind that the objects of study, the conditions of their functioning, the goals and objectives of the system in the process of their development can change (and in the process of the life cycle of the system), therefore the system analysis is an iterative process, that is, part of the stages or the entire cycle of analysis can cyclically repeat.

Learning the systems approach instills a mindset that, on the one hand, helps to eliminate unnecessary complexity, and on the other hand, helps the leader to understand the essence of complex problems and make decisions based on a clear understanding of the environment. It is important to structure the task, to outline the boundaries of the system. But it is just as important to consider that the systems that a leader has to deal with in the course of his work are part of larger systems, perhaps involving an entire industry or several, sometimes many, companies and industries, or even society as a whole. Further, it should be said that these systems are permanent.

They change, they are created, operate, reorganized, and, sometimes, are liquidated.

In most cases of practical application of system analysis for the study of properties and subsequent optimal control of the system, the following can be distinguished main steps:

2. Building a model of the system under study.

3. Finding a solution to a problem using a model.

4. Verification of the solution using the model.

5. Adjusting the solution to external conditions.

6. Implementation of the decision.

In each specific case, the stages of the system take a different "share" in the total volume of work in terms of time, cost and intellectual indicators. It is very often difficult to draw clear boundaries - to indicate where a given stage ends and the next begins.

System analysis cannot be fully formalized, but you can choose some algorithm for its implementation.

System analysis can be performed in the following sequences:

1. Formulation of the problem- the starting point of the study. In the study of a complex system, he is preceded by work on structuring the problem.

2. Expanding the problem to the problematic, i.e. finding a system of problems that are essentially related to the problem under study, without which it cannot be solved.

3. Revealing goals: goals indicate the direction in which to move in order to gradually solve the problem.

4. Formation of criteria. A criterion is a quantitative reflection of the degree to which the system has achieved its goals. A criterion is a rule for choosing a preferred solution from a number of alternative ones. There can be several criteria. Multi-criteria is a way to improve the adequacy of the goal description. The criteria should describe as far as possible all the important aspects of the goal, but the number of criteria needed should be minimized.

5. Aggregation of criteria. The identified criteria can be combined either into groups or replaced by a generalizing criterion.

6. Generating alternatives and selection using the criteria of the best one. The formation of many alternatives is the creative stage of systems analysis.

7. Research on resource opportunities, including information resources.

8. Choice of formalization(models and constraints) to solve the problem.

9. Building the system.

10. Using the results a systematic study carried out.

The scheme of the algorithm for solving the problems of the systemic study of a specific problem is shown in Fig. 6.1.

Figure 6.1. Algorithm for solving problems of a systemic study of a specific problem

Formulation of the problem. For traditional sciences, setting a problem is the starting point of work. For systems researchers, this is an intermediate result, preceded by a lot of analytical work.

For example, recently the problem of non-payment of wages has been acute in organizations. But non-payment of wages is not a problem, but a consequence, as a rule, of a certain set of problems, which is different for each organization.

The initial formulation is only a rough hint of what the problem formulation should actually be. As a rule, management and organizational development consultants are involved in identifying the problem field and processing it.

Further, goals are identified that are antipodes to problems. Problems are what we don't like, and goals are what we want. As a result, the problems are reduced to such a form when they become the tasks of choosing the appropriate means necessary to achieve the set goals.

When formulating goals, you should adhere to the following rules:

  • include in the list goals that are opposite to those stated;
  • to identify not only desirable, but also undesirable goals in terms of consequences;
  • admit the existence of any goals at all.

Changing goals in time can be both in form and

Formation of criteria. Criteria are quantitative models of qualitative goals; similarity of the goal, its approximation, model.

For example, a student sets a goal for himself: to pass the winter session successfully. The criterion in this case can be such a quantitative model - to get two fives and two fours.

The solution may consist not only in finding a more adequate option (it may happen that it does not exist), but also in the use of several criteria describing the same goal from different positions and thereby complementing each other.

For example, the goal is to improve garbage collection in a city. The evaluation criteria can be as follows.

The first group of criteria ".

  • garbage collection costs per apartment;
  • the amount of garbage per person per day;
  • the total weight of the garbage to be removed.

The second group of criteria ".

  • the percentage of residential areas with a low incidence rate of the population;
  • reduction in the number of fires;
  • reduction in the number of complaints from residents.

Generating alternatives and choosing a solution to problems.

In the presence of goals and criteria for their achievement, questions arise,

what to evaluate by these criteria, from what to choose. Many problems to be solved cannot be quantified, therefore expert technologies are used. In a word, we need experts and solutions. The block diagram of expert decision making methods is shown in Fig. 5.2.

(comparative preference score)

Generating alternatives

(search for non-standard solutions)

Expert classification

(determination of the belonging of the elements of the set under study to any classes)

Expert forecast

(assessment of trends in expected development) Individual

_ / expert / _

Collective "Brainstorming"

(consistent search for a non-trivial solution in which criticism of ideas is prohibited)

Delphi

(anonymous agreement of individual opinions, carried out in several rounds)

Scripts

(identifying trends of possible development: putting forward hypotheses)

Ships

(discussion of alternatives: supporters, opponents and "judges")

Commissions

(regular development of agreed opinions at meetings)

Rice. 5.2. Block diagram of expert decision making methods

Let us consider in more detail the methods of activating creative thinking.

Brainstorming method. The essence of the method: each member of the group is given the right to express a variety of ideas about the options for solving the problem, regardless of their validity, feasibility and consistency. The more different offers, the better. The leader leads the "attack". The participants in the group work get acquainted with information about the nature of the problem in advance. All suggestions are listened to without criticism or evaluation (the moderator monitors this), and their analysis is carried out centrally after the end of the process of expressing an idea on the basis of notes produced by the secretariat. As a result, a list is formed in which all submitted proposals are structured according to certain parameters (criteria), as well as their effectiveness in solving the problem under discussion.

Delphi method. This method is often used when group gathering is not possible. According to the procedure, team members are not allowed to meet and exchange views on the problem being solved; this ensures independence of opinion. The procedure is as follows (it goes through the stages):

  • 1) the members of the group are invited to answer a list of questions formulated in detail on the problem under consideration;
  • 2) each participant answers the questions anonymously;
  • 3) the results of the answers are collected in the center, and based on the results of processing the answers, an integral document is drawn up containing all the proposed solutions;
  • 4) each member of the group receives a copy of the integral document;
  • 5) familiarization with the specified document (analysis of proposals of other group members) may change the opinion of some group members regarding possible solutions;
  • 6) steps 3 through 5 are repeated as many times as necessary to achieve an agreed solution.

This method is applicable when there is no time limit for making a decision and decisions are made by experts. When developing solutions for a specific organization for the purpose of subsequent implementation, it is advisable to use other methods of group work that allow finding consensus, and in the process of finding solutions from the members of the group (the leadership of the organization), a team of like-minded people can be formed.

The method of expert assessments. The basis of this method is the use of various forms of expert survey, followed by assessment and selection of the preferred option. The objectivity of expert assessments is based on the fact that an unknown characteristic of the phenomenon under investigation is interpreted as a random variable, the reflection of the distribution law of which is an expert's individual assessment of the reliability and significance of a particular event. The true value of the investigated characteristic is within the range of assessments received from experts.

The goal tree method is developed on the basis of a systematic analysis of problem situations and involves the use of a hierarchical structure obtained by dividing a common goal into subgoals. A "tree of goals" is created to analyze a problem situation and visualize the results of such an analysis. The idea of ​​developing a "tree of goals" belongs to the American researcher Churchman, who applied this approach to the study of the problems of industrial development. In this case, the "goal tree" is a connected graph without cycles. Thus, "Goal tree" - it is a graph expressing the subordination and interconnection of elements, which are goals and resources.

When constructing a "tree of goals", the trends of the expected development of events are established by expert forecasts. Determination of the main factors influencing the development of the situation is carried out by the method of developing scenarios. Scenarios are hypothetical alternative descriptions of what might happen in the future. Scenarios are not just a figment of fantasy, but logical models of the future, a kind of story about "what happens if ...". Usually several scenarios are developed: optimistic, pessimistic and intermediate. Before developing a scenario, lists of factors affecting the course of events and available resources are made.

The search for non-standard solutions to a newly arisen problem is carried out by methods of generating alternatives. The comparative preference of various alternatives is assessed by the method of determining ratings or by methods of forming assessment systems. They include assessment criteria, criteria measurement scales, rules for choosing the most preferred alternative. This method is used when the goal is unclear, and there is only the initial state of the system.

The events of the lower level of decomposition are ranked according to their preference and probability of occurrence (Fig. 5.3).

The most preferred option is the target of the system.

Methods of morphological analysis are based on combining the selected elements or their features in the process of finding solutions to problems. Within the framework of this method, all possible elements are determined, on which the solution of the problem may depend, the possible values ​​of these elements are enumerated, and then the process of generating alternatives begins by enumerating all possible combinations of these values.

Rice.

The method of negation and construction. Some assumptions are formulated and replaced with opposite ones, followed by an analysis of the inconsistencies that arise.

The method of systematic coverage of the field consists in the allocation of strong points of knowledge in the studied area, which are used to fill in the field of some formulated principles of thinking.

The synectics method is designed to generate alternatives through associative thinking, searching for analogies to the task at hand. It is as follows:

  • 1) a group of 5-7 people is formed with flexible thinking, experience, psychological compatibility, sociability and mobility;
  • 2) skills of joint group work are developed;
  • 3) not only known similar solutions are sorted out, but also all possible and impossible (fantastic) solutions;
  • 4) it is forbidden to discuss the merits and demerits of the members of the group;
  • 5) everyone is allowed to stop working at any time without giving reasons;
  • 6) the role of the leader is periodically transferred to other members of the group.

Unlike the brainstorming method, this requires a special and lengthy preparation of the group.

Business games are simulations of real situations, but the "players" behave as if it were happening in real life. This situation removes the barriers that exist in reality: shyness in front of bosses and colleagues, prohibition of job descriptions, lack of necessary information, the ability to use any fantasies (for example, the business game "marketing").

The final decision and the choice of an option from the proposed alternatives is made, as a rule, by an expert. However, questions arise here as well. Even the results of expert assessments processed by appropriate methods do not guarantee that the best solution will be made. In addition, a decision made without the participation of those who have to implement it is usually difficult to implement. The challenge is for the experts and people implementing this solution to become like-minded people.


2014

Didactic content of the course:

information support, information systems, databases, database management systems; life cycle of an information system; external design, main stages of information systems design, structural methodology, functional design SADT - technologies; basic requirements for organizing a dialogue and presenting data; conceptual, logical and physical design of databases; entity-relationship data model, relational system, network and hierarchical data models; data description languages ​​and data manipulation languages ​​in database management systems; physical organization of data, access methods; multitasking and multiuser information systems; schedules and protocols; data protection and privacy.


Basic concepts of systems theory

Under the termsystem we will understand a set of elements that are in relationships and connections with each other, which forms a certain integrity, unity.

The set of elements existing outside the system that affect the system, or, conversely, that the system affects, are called the external environment of the system.

If the elements of a system are themselves systems, then they are usually called subsystems of this system.

Any system, in turn, can be an element of another higher-level system ( supersystem).

System characteristics and properties

The nature of systems can be very diverse. There are material, abstract systems (concepts, hypotheses, theories ...), social, technical, informational, biological, pedagogical, etc. But all systems have a single set of characteristics, although the values ​​of the characteristics themselves are different.

Any system has:

1. The goals of creation (existence) of the system;

2. The set of connections and relationships between parts of the whole, necessary to achieve the goal (structure);

3. External links (with other systems);

4. Resources consumed by the system (inputs) - information, material, energy;

5. Products generated by the system (outputs);

6. System functioning (behavior).

It is customary to divide systems into complex and simple. It should be noted that the concept of the complexity of the system has not yet been finally formulated.The distinctive features of the internal complexity of the organization of the system are considered the complexity of the structure and the set of internal states, potentially estimated by the manifestations of the system, as well as the complexity of control in the system. The external complexity of the organization of the system is characterized by the complexity of the relationship with the environment. One and the same system can be represented by different structures depending on the stage of cognition of objects or processes, on the aspect of their consideration, the purpose of creation. At the same time, as research develops or in the course of design, the structure of the system may change.

Let's highlight the important properties of the systems:

ü According to the definition, the main property of the system is its integrity, that is, the appearance of such new properties that each of its parts does not have separately.

ü The main property of complex systems is the presence of a goal.
Any system is created to achieve some goals. Large systems tend to be multipurpose. Under the influence of external conditions and over time, goals can change.

ü Each system is created in the interests of a higher level system.

ü The most important property of complex systems is their ability to control and self-government. Management is needed to more effectively fulfill goals.

ü Systems can exchange matter, energy and information.

ü Complex systems are characterized by heterogeneity of parts, for example, in composition and function.

ü In the course of their life, systems go through 4 significant stages: origin, development, aging, death.


System structures

System structures are of different topology (or spatial structure). Let's consider the main topologies of system structures. The corresponding schemes are shown in the figures below.

Linear structure:

Hierarchical (tree) structure:


Network structure:

Matrix structure (tabular):


In addition to these basic types of structures, others are also used that are formed with the help of their correct combinations - connections and attachments.

For example,"Nesting into each other" of planar matrix structures can lead to a more complex structure - a spatial matrix structure (for example, a substance of a crystal structure

Crystalline type structure (space-matrix):

Stages of system analysis

System analysis- a system of concepts, methods and technologies for the study, description, implementation of systems of various nature and character, interdisciplinary problems; it is a system of general laws, methods, techniques for studying such systems.

The foundations of systems analysis were laid by the Russian scientist, philosopher, economist and physician Alexander Alexandrovich Bogdanov (1873-1928).

He suggested that in matters of organizing various large systems in nature, society, technology, there is much in common, and the most different systems of the surrounding world can be studied using the same methods.

System analysis is based on a systematic approach to the study of objects, which is based on the consideration of any objects as systems.

Summarizing the research of scientists in the field of systems analysis, the following stages of system analysis of various objects as systems can be distinguished:

1. formulation of goals, their priorities and research problems;

2. definition and refinement of research resources;

3. allocation of the system (from the environment) using resources;

4. definition and description of subsystems;

5. definition and description of the integrity (connections) of subsystems and their elements;

6. analysis of interconnections of subsystems;

7. building the structure of the system;

8. establishing the functions of the system and its subsystems;

9. coordination of the goals of the system with the goals of the subsystems;

10. analysis (testing) of system integrity;

11. analysis and assessment of the systemic effect.

Control systems

In 1948, the American scientist Norbert Wiener (1894-1964) formulated the main provisions of a new science, which he called cybernetics. He introduced a new category into consideration - "management".

The set of control actions aimed at achieving the set goal is called management. Thus, management assumes that there is some body that develops control actions. Such a governing body is usually called control system. The control object, to change the state of which the control actions are directed, are called controlled system.

In order for the control goal to be achieved, the control system must receive information about the state of the controlled system. Information about the state of the controlled system allows you to adjust the control actions.

Information Systems

Information system(in the context of management) is a communication system for the collection, transmission, storage and processing of information about the object of management.

An information system (IS) usually includes the following components:

1. functional components;

2. components of the data processing system;

3. organizational components.

Under functional components the system of control functions is understood - a complete set of interconnected in time and space control works necessary to achieve the tasks set for the controlled system.

Data processing systems are designed to provide information services to specialists in the management system who make management decisions. The components of this system are: Information Support, software, hardware, legal support, linguistic support.

The selection of the organizational component is due to the special significance of the human factor.

Life cycle information system consists of several stages: analysis, design, implementation, implementation, maintenance. Consider two life cycle models - cascade and spiral:

The benefits of using the waterfall approach are as follows:

ü at each stage a complete set of project documentation is formed that meets the criteria for completeness and consistency;

ü The stages of work performed in a logical sequence allow you to plan the timing of the completion of all work and the corresponding costs.

However, in the process of using the cascade approach, a number of its shortcomings are revealed, caused primarily by the fact that the real process of creating an information system never fully fits into such a rigid scheme. In the process of creating a system, there is a constant need to return to previous stages and clarify or revise previously made decisions. To overcome these problems, a spiral life cycle model was proposed, emphasizing at the initial stages of life cycle: analysis and design.

At these stages, the feasibility of technical solutions is checked by creating prototypes... Each turn of the spiral corresponds to the creation of a fragment or version of the system, on it the goals and characteristics of the project are specified, its quality is determined, and the work of the next turn of the spiral is planned. Thus, the details of the project are deepened and consistently specified, and as a result, a reasonable option is selected, which is brought to implementation.

The first type of prototype is graphical system model(SADT -models will be considered below), understandable by users. From such diagrams, the general architecture of the system becomes clear.

The second type of prototype is screen layouts allowing you to match database fields and user-specific functionality.

The third type of prototype is working screen forms, i.e. already partially programmed. This allows you to try out the program in action. As a rule, this triggers a new stream of comments and suggestions.

In accordance with the stages of the life cycle of an information system, several categories of specialists providing this life cycle can be distinguished: system analysts, programmers, users-specialists in a specific subject area.