2.4. content and methods of design work
The creation of automated information systems and technologies in the economy can be carried out according to two options. The first option assumes that this work is carried out by specialized companies with professional experience in preparing software products specific orientation (industrial accounting, accounting in banks, automation of specific banking operations etc.), their sales and further support in organizations operating the supplied software and systems. If AIS and AIT are created according to the second option, the design and creation of developments in this area are carried out by designers and programmers who are on the staff of enterprises and organizations where the transition to the use of new technical means is taking place, new ones are created information Technology and systems. There are currently two extremes in design work. In one case, the standards for producing documentation are strictly observed, but the development time is greatly delayed, the creation of the system does not fit into the rhythm of real life and it turns out to be unviable. In another case, the ability of developers to create programs to automate the solution of individual tasks allows them to ensure the process of using developments by the end user without delays; the system begins to work, but the creation of documentation lags behind and the result is a product that is labor-intensive to operate, and its development largely depends on specialists -developers. This contradiction can be overcome if design discipline is observed.
On development stage automated systems, workplace and technology designers face a number of interrelated challenges.
It is difficult for a designer to obtain comprehensive information to assess the requirements formulated by the customer (user) for a new system or technology.
The customer often does not have sufficient knowledge about the problems of automating data processing in a new technical environment to judge the possibility of implementing certain innovations. At the same time, the designer is faced with an excessive amount of detailed information about the problem area, which causes difficulties in modeling and formalizing the description of information processes implemented in new conditions and solving functional problems.
Specification of the designed system due to the large volume and technical terms is often incomprehensible to the customer, and its excessive simplification cannot satisfy the specialists creating the system.
With the help of well-known analytical methods, some of the listed problems can be resolved, but a radical solution is provided only by modern structural methods, among which the methodology of structural analysis occupies a central place.
Structural analysis is usually called a method of studying a system, which begins with its general overview and then gets detailed, acquiring a hierarchical structure with an increasing number of Levels. Structural analysis involves dividing the system into levels of abstraction with a limited number of elements at each level (usually from 3 to 6-7). At each level, only the details essential to the system are highlighted. Data is considered in conjunction with the operations performed on it. Strict formal rules are used for recording elements of information, drawing up a system specification, and consistently approaching the final result.
The methodology of structural analysis is based on a number of general principles, some of which regulate the organization of work at the initial stages life cycle created information system, and some are used in developing recommendations for organizing work. The two basic principles are the principle of decomposition and the principle of hierarchical ordering. The first principle involves solving difficult problems of structuring complexes of functional tasks by breaking them down into many smaller independent tasks that are easy to understand and solve. The second principle declares that the structure of these parts is also essential for understanding with a detailed formalized description of them. The understandability of a problem increases dramatically when its parts are organized into tree-like hierarchical structures, that is, the system can be understood and built in levels, each of which adds new details.
At the pre-design stage, a study and analysis of all the features of the design object is carried out in order to clarify the customer’s requirements, their formalized presentation and documentation. In particular, a set of conditions under which it is expected to operate the future system is identified (hardware and software resources provided to the system; external conditions of its functioning; composition of people and works related to it and participating in information and management processes), a description of the functions performed by the system is made and so on. At the same stage, restrictions are established in the development process (directive deadlines for completing individual stages, available resources, organizational procedures and measures to ensure information protection, etc.).
The purpose of analysis at this stage is to transform general, unclear knowledge about the requirements for future system into precise (if possible) definitions. So, at this stage the following are determined:
System architecture, its functions, external conditions, distribution of functions between hardware and software;
Interfaces and distribution of functions between a person and the system;
Requirements for software and information components of the system, necessary hardware resources, database requirements, physical characteristics of system components, their interfaces.
The quality of further design depends decisively on the right choice methods of analysis, formulated requirements for the newly created technology. These methods serve to conduct study and research, development and evaluation of design solutions laid down when creating an AS, as well as to ensure cost savings and reduce the time required for design and implementation of the system.
The methods used at the stage of pre-project inspection are divided into methods for studying and analyzing the actual state of the object (technology), methods for forming a given state, methods for graphically representing the actual and given states (Fig. 2.2). Let's look at these methods in more detail.
Methods for studying and analyzing the actual state economic object or technology. These methods allow you to identify bottlenecks in the processes under study and include:
Oral or written survey;
Written survey;
Observation, measurement and evaluation;
Group discussion;
Task analysis;
Process analysis.
Oral and written survey. An oral survey is carried out using a pre-compiled questionnaire at the specialist’s workplace with the answers recorded and allows, in the form of a simple conversation, to understand the work technology and experience of the interviewee. Psychological difficulties are easily overcome and you can begin to prepare a new solution already at the analysis stage. The disadvantage of this method is the heterogeneity of the survey results.
Rice. 2.2. Works and methods of their implementation at the pre-design stage
A written survey using a list of questions provides (provided the respondents are ready to give truthful answers) complete and thorough information. When enough large quantities questionnaires are processed on a computer. To improve the quality of the survey, it is advisable to introduce a response prompt: “yes - no”, “small - medium - large”, etc. The clarity and unambiguity of the questions have a significant impact on the quality of the results, so developing a list of questions presupposes knowledge of the fundamental problem situation.
Observation, measurement and evaluation. Using these methods, information about parameters, characteristics and objects in the relevant field of study is collected. Parameters, characteristics and objects important for study are accurately assessed by employees and recorded on cards or forms (for example, by frequency, quantity, duration, costs). The accumulation of information and analysis of results with a sufficiently large number of observations is carried out on a computer.
Group discussion is carried out by designers, programmers together with users or customers with the aim of summarizing and discussing all issues important for solving problems and identifying the necessary tasks.
Task analysis. The essence of this method is the vertical and horizontal structuring of tasks and their distribution among performers (job descriptions) based on the given structure of the object. Tasks are broken down to such an extent that it is possible to determine results, decisions, powers, algorithms, input and output information. Task analysis is the first stage and prerequisite for describing tasks, which are the basis for building a technology for obtaining results, developing job descriptions and plans for the distribution of functions when working in new technological conditions. The starting point for the analysis is the requirements for the object and its information system.
Analysis of production, management and information processes is used to prepare decisions regarding the reorganization of information process technology. By analyzing the problem-solving process, the necessary changes that must be made to information technology are developed. At the same time, the target settings of the tasks being solved are clarified.
Analysis of production, management and information processes should primarily cover the following: the object being examined; the purpose and result of solving management problems; components of the technological process - decisions, operations and algorithms; volume and quality of information; information processing tools; requirements for management personnel and workplace; working methods; bottlenecks, obstacles, difficulties; requirements for rational organization of the technical process.
In general, methods for studying and analyzing the actual state of management activities and existing technology for solving problems are intended to establish and evaluate processes, functions, requirements for employees, and the sequence of implementation technological operations and means of labor, duration and timing of work, information flows. They contribute to the collection of necessary materials and the formation of the necessary initial basis for the design of AIS and AIT.
Methods for forming a given state. They are based on a theoretical justification of all components and elements of the AIS based on the goals, requirements and conditions of the customer. These methods, which are working tools for designers, include the following methods:
Modeling of the management process;
Structural design;
Decomposition;
Information process analysis.
Method for modeling the management process. In the process of studying the design object, economic-organizational and information-logical models are built, which include the tasks, structures and resources of the object. They reflect economic and management relations, as well as information flows associated with them. By presenting a combination of material and information processes, they contribute to increasing the level of organization of the object.
Information-logical models contain the necessary information about information connections between bodies and areas of management, complexes of tasks to be solved and individual tasks in unity with economic processes.
The method of structural (modular) design allows you to develop a project of clearly demarcated blocks (modules), between which connections are established through input and output information, and the hierarchy of their subordination is also shown. The conditions for using this method are the division of large complexes of problems into subcomplexes and the precise designation (identification) of all links of separation and coupling. The structural design method allows you to divide the entire complex of problems into observable and analyzable subcomplexes (modules).
The module decomposition method provides for further division of subcomplexes of tasks into separate tasks and indicators. The top-down approach to breaking down the entire set of tasks is especially convenient for developing fundamental organizational and technical solutions, making changes to them if necessary, as well as linking economic and organizational and managerial targets with specific tasks and indicators when designing.
Analysis and modeling of information processes is intended to identify and present in each case the relationship between the result, the processing process and data input. It is also used to analyze and form information links between the workplaces of management workers, specialists, technical personnel and information technology. For this purpose, input and output information is described, as well as an information processing algorithm in relation to each workplace. By detecting and sequentially connecting numerous chains of data processing and transmission, complex information processes are formed and the information needs of individual users are taken into account.
Methods for graphical representation of actual and specified states involve the use of visual representation of information processing processes in the form of flowcharts, document flow charts, etc. Graphic methods are an integral part of any project and are necessary for practical work, since they serve as an auxiliary tool in describing the implementation of new technologies. The most famous of them include the flowchart method, methods of arrow diagrams, network diagrams, tables of the sequence of operations of processes. The differences between the methods are expressed in the degree of their implementation on a PC, clarity, and the depth of the reflected processes.
If at the pre-design stage the features of the design object must be carefully analyzed and the requirements for the creation of AIS and AIT must be clearly formulated in the technical specifications, then the design must answer the question:
“How (how) will the system satisfy the requirements placed on it?” The task of this stage is to form a new structure of the system and the logical relationships of its elements that will function on the proposed technological platform. Design implements an iterative process of obtaining a logical model of the system along with strictly formulated goals set for it, as well as writing specifications physical system, satisfying these requirements. Typically the design stage is divided into two stages.
1. Creation of design solutions, design of AIS architecture, including development of the structure and interfaces of components, coordination of functions and technical requirements for components, design methods and standards, production of reporting documents.
2. Detailed (detailed) design, including the development of specifications for each component and, above all, the creation or binding of software, interfaces between components, the development of a component integration plan, and the generation of extensive instructional materials.
As a result of the design stages, a system design should be obtained that contains enough information to implement the system within the budget of the allocated resources and time.
When developing an AIS and AIT project, division of labor, cooperation and communication between developers and customers are ensured. As the level of design increases, the responsibility for making design decisions increases repeatedly. To ensure high-quality implementation of the project, the stages of system development are linked to the process of organizing design work, which includes the following: development of goals, objectives and organizational principles when setting the task; formation of a fundamental design solution when developing the project concept and variant of AIS and AIT; material and technical implementation of design work during the preparation and debugging of programs; testing of organizational solutions during trial operation and delivery of the AIS and AIT project; use of design and organizational solutions in the operation of AIS and AIT.
The stages of the process of organizing and conducting design work reflect the fundamental path of development and implementation of new design solutions. This standard concept is suitable for organizing design with various forms of using labor tools, including the use of PCs and design automation. This does not take into account the nature of the problems to be solved in a particular case. Based on a typical design organization concept, each stage can be refined depending on the repeating work operations. Then, for each AIS and AIT project, the work to be performed is selected and compiled into a schedule. Depending on the nature and complexity of the problems being solved, it may be necessary to perform certain steps multiple times. Within the framework of work stages, it is envisaged that individual performers will be assigned responsibility for the development of tasks, project stages and programs.
In the process of organizing the design, various decisions are made that affect the dynamics and quality of work. Therefore, for each design stage the following are determined: expected results and documents; personal functions manager; decisions made by the manager; functions of the customer and developer of AIS and AIT.
Coordination with work carried out in parallel over time during the selection, training, release and relocation of personnel, as well as during the preparation and implementation of investment activities and other work, is necessarily included in the content of the work stages and is reflected in the design and executive documentation.
As-built documentation relates to individual processes, areas and is developed within the framework of the entire projected AIT. The documentation includes: organizational instructions for work processes, programs for workplaces, instructions for preparing documents, recommendations for the use of information, methods, decision tables, etc.
Having characterized the content of design work when creating AIS and AIT, one cannot help but dwell on the currently most common methods of conducting design work.
IN modern conditions AIS, AIT and AWS, as a rule, are not created from scratch. In the economy, automated information processing systems operate at almost all levels of management and at all economic entities - from regional government bodies, financial and credit organizations, enterprises, firms to trade organizations and service sectors. However, the transition to market relations, the increased need for timely, high-quality, operational information and its assessment as the most important resource in management processes, as well as the latest achievements of scientific and technological progress, necessitate the restructuring of functioning automated information systems in the economy, the creation of automated information systems and AIT on a new technical and technological basis. Only new technical and technological conditions - modern AIT - will make it possible to implement the much-needed market conditions fundamentally new approach to the organization of management activities of an economic object as engineering activities, called “reengineering”.
The term "reengineering" was introduced by M. Hammer; it provides for a radical redesign of business processes (business processes) to achieve sharp, abrupt improvements in indicators of cost, quality, service, and the pace of development of firms, companies, enterprises, and organizations based on AIT. Reengineering primarily involves restructuring the economic activities of an economic entity on the basis of new information technology. At the same time, AIS and AIT, their technical, software, Information Support, the redesign of which is carried out on the basis of a newly created abstract model of the revised original system.
The search for rational design paths is carried out in the following areas: development of standard design solutions recorded in application software packages (APP), solutions economic tasks with subsequent linking of PPP to specific conditions of implementation and operation, development of computer-aided design systems. Let's consider the first of the paths, i.e. Possibility of using standard design solutions included in application packages.
The following types of activities lend themselves most effectively to informatization: accounting, reference and information support for economic activities, organization of managerial work, document flow, economic and financial activities, education.
The largest number of PPPs have been created for accounting. Among them are “1C: Accounting”, “Turbo-Accountant”, “Info-Accountant”, “Parus”, “ABACUS”, “Bambi+”, “Accounting Complex”, “Best”, “Luka”.
Reference and information support for economic activities is presented by the following PPP: “GARANT”: (taxes, accounting, audit, entrepreneurship, banking, currency regulation, customs control), “CONSULTANT+”, (taxes, accounting, audit, entrepreneurship, banking, currency regulation, customs control).
Economic and financial activities are supported by the following PPPs:
« Economic analysis and forecast of the activities of a company, organization" (INEK company), implementing the functions: economic analysis of the activities of a company, enterprise; business plan; feasibility study of loan repayment; analysis and selection of activity options; forecast of balance, flows Money And finished products;
“Financial analysis of an enterprise” (Infosoft company), implementing the functions: overall rating financial condition; financial stability analysis; balance sheet liquidity analysis; analysis of financial ratios (liquidity, agility, coverage, debt-to-equity ratio); coefficient analysis business activity; calculation and analysis of turnover ratios; assessment of production profitability. In the field of creating financial and credit systems, the companies “Dia-soft”, “Inversion”, R-Style, Programbank, “Asoft”, etc. work.
In a competitive environment, those enterprises whose business strategies are combined with information technology strategies win. That's why real alternative An option for choosing a single package is to select a certain set of packages from different suppliers that best satisfy a particular AIS function (mix-and-match approach). This approach mitigates some of the problems that arise during the implementation and binding of software tools, and AIT will be more consistent with the functions of a specific domain personality.
IN Lately an increasing number of banks, organizations, and enterprises prefer to buy ready-made packages and technologies, and if necessary, add their own to them software, since the development of your own AIS and AIT is associated with high costs and risk. This trend has led system providers to change their previous way of going to market. As a rule, a basic system is now developed and offered, which is adapted according to the wishes of individual customers. At the same time, users are provided with consultations that help to minimize the implementation time of systems and technologies, use them most effectively, and improve the qualifications of personnel.
For example, the Internet banking AIS Atlas is designed for any possible system configurations. Banks can, using their own staff, customize the system configuration to suit their requirements. For this purpose, the Atlas system has a full set of development tools - training, consultation and support.
The situation is similar when developing AIS in other areas of the economy. For example, the development of AIS for insurance activities is only within the capabilities of specialized organizations that generalize practical experience work of insurers, closely interacting with auditing organizations and having a staff of highly qualified task setters and programmers.
Automated design systems are the second, rapidly developing way of conducting design work.
In the field of automation of design of AIS and AIT over the last decade, a new direction has been formed - CASE (Computer-Aided Software/System Engineering). The avalanche-like expansion of the areas of application of PCs, the increasing complexity of information systems, and increasing requirements for them have led to the need to industrialize the technologies for their creation. An important direction in the development of technologies was the development of integrated tools based on the concepts of life cycle and quality management of AIS and AIT, which are complex technologies aimed at creating complex automated management systems and support for their full life cycle or a number of its main stages. Further development Work in this direction led to the creation of a number of conceptually holistic options, equipped with high-level design and implementation tools, brought in quality and ease of replication to the level of software products of technological systems, which were called CASE systems or CASE technologies.
There is currently no generally accepted definition of CASE. The content of this concept is usually determined by the list of problems solved using CASE, as well as the set of methods and tools used. CASE technology is a set of methods for analysis, design, development and maintenance of automated information systems, supported by a complex of interconnected automation tools. CASE is a toolkit for system analysts, developers and programmers that allows you to automate the process of designing and developing automated systems, which has become firmly established in the practice of creating and maintaining automated information systems and automated information systems. At the same time, CASE systems are used not only as complex technological conveyors for the production of AIS and AIT, but also as a powerful tool for solving research and design problems, such as structural analysis of the subject area, specification of projects using fourth-generation programming languages, release project documentation, testing project implementation, planning and control of developments, modeling business applications in order to solve problems of operational and strategic planning and resource management, etc.
The main goal of CASE technology is to separate the design of AIS and AIT from its coding and subsequent stages of development, as well as to automate the processes of development and operation of systems as much as possible.
When using CASE technologies, the technology for conducting work at all stages of the life cycle of automated systems and technologies changes, with the greatest changes affecting the stages of analysis and design. Most modern CASE systems use structural analysis and design methodologies based on visual diagramming techniques, and graphs, diagrams, tables and diagrams are used to describe the model of the designed AIS. Such methodologies provide a rigorous and visual description of the designed system, which begins with its general overview and then becomes detailed, acquiring a hierarchical structure with an increasing number of levels.
CASE technologies are successfully used to build almost all types of AIS, but they occupy a stable position in the field of ensuring the development of business and commercial AIS. The widespread use of CASE technologies is due to the widespread use of this application area, in which CASE is used not only to develop automated information systems, but also to create system models that help commercial structures solve problems of strategic planning, financial management, determining company policies, personnel training, etc. This The direction received its own name - business analysis. For example, financiers are increasingly turning to CASE technology to develop a high-quality banking system as quickly and efficiently as possible. Providers of this technology are stepping into the shoes of financiers and are rapidly expanding the market for funds. The rapid implementation of CASE technology is also facilitated by the increasing complexity of banking systems.
CASE is not a revolution in automation of AIS design, but the result of the natural evolutionary development of the entire industry of tools, previously called instrumental or technological. One of the key features is support for structural systems analysis and design methodologies.
From the very beginning, the goal of the development of CASE technologies was to overcome the limitations of using structural design methodologies of the 1960s and 1970s. (difficulty of understanding, high labor intensity and cost of use, difficulty in making changes to design specifications, etc.) due to their automation and integration of supporting tools. Thus, CASE technologies cannot be considered independent methodologies; they only develop structural methodologies and make their application more efficient through automation.
In addition to the automation of structural methodologies and, as a consequence, the possibility of using modern methods systems and software engineering, CASE technologies have the following main advantages:
Improve the quality of created AIS (AIT) through automatic control means (primarily project control);
They allow you to create a prototype of a future automated information system (AIT) in a short time, which makes it possible to evaluate the expected result at an early stage;
Speed up the process of system design and development;
They free the developer from routine work, allowing him to concentrate entirely on the creative part of development;
Support the development and support of the development of AIS (AIT);
Support technologies for reusing development components.
Most CASE tools are based on a scientific approach called methodology/method/notation/tool. The methodology formulates guidelines for assessing and selecting the project of the developed AIS, work steps and their sequence, as well as rules for the application and purpose of methods.
To date, CASE technology has developed into an independent science-intensive direction, which has led to the formation of a powerful CASE industry that unites hundreds of firms and companies of various orientations. Among them are companies developing analysis and design tools for AIS and AIT with a wide network of distribution and dealer companies; companies that develop special tools focusing on narrow subject areas or on individual stages of the AIS life cycle; training companies that organize seminars and training courses for specialists; consulting firms providing practical assistance in using CASE packages for the development of specific AIS; companies specializing in the production of periodical magazines and newsletters on CASE technologies.
Almost no serious foreign AIS and AIT projects are currently being implemented without the use of CASE tools.
Without the development of methods for designing management structures, it becomes difficult to improve management and increase production efficiency, since:
Firstly, in new conditions, in a number of cases, it is impossible to operate with old organizational forms that do not meet the requirements of market relations and create the danger of deformation of the management tasks themselves;
Secondly, it is impossible to transfer the laws governing the management of technical systems into the sphere of economic management. An integrated approach to improving the organizational mechanism was largely replaced by the introduction and use of automated control systems (ACS) - work that is extremely important, but not the only one in the development of management at all levels. The creation of automated control systems is often carried out in isolation from improving the management structure and is not sufficiently connected with organizational factors;
Thirdly, the creation of a structure should be based not only on experience, analogy, familiar patterns and, finally, intuition, but also on scientific methods of organizational design;
fourthly, the design of the most complex mechanism - the control mechanism - should be entrusted to specialists who master the methodology for the formation of organizational systems.
When developing principles and methods for designing management structures, it is important to move away from the representation of the structure as a frozen set of organs corresponding to each specialized management function. Organizational management structure is a multifaceted concept. It primarily includes a system of goals and their distribution between various units, since the management mechanism must be focused on achieving goals. This also includes the composition of units that are connected by certain relationships; distribution of tasks and functions across all levels; distribution of responsibilities, powers and rights within the organization, reflecting the relationship between centralization and decentralization of management. Important elements of the management structure are communications, information flows and document flow in the organization. Finally, an organizational structure is a behavioral system; it is people and their groups constantly entering into various relationships to solve common problems.
Such versatility of the organizational mechanism is incompatible with the use of any unambiguous methods, either formal or informal. That is why it is necessary to proceed from a combination of scientific methods and principles of structure formation (system approach, program-target management, organizational modeling) with export-analytical work, the study of domestic and foreign experience, close interaction between developers and those who will practically implement and use the designed organizational structure mechanism. The methodology for designing structures should be based on a clear formulation of the organization's goals. First, goals are formulated, and then the mechanism for achieving them. At the same time, the organization is considered as a multi-purpose system, since focus on one goal does not reflect its diverse role in economic development.
Of particular importance are the nature of the influence of the external environment on the construction of the organization and the system of connections between the elements of the structure and the elements external environment(Fig. 28.1).
The systematic approach to the formation of an organizational structure is manifested in the following: 1) do not lose sight of any of the management tasks, without the solution of which the implementation of goals will be incomplete; 2) identify and interconnect, in relation to these tasks, a system of functions, rights and responsibilities along the vertical management - from general director enterprises to the site foreman; 3) explore and institutionalize all connections and relationships along the management horizontal, i.e., coordinating the activities of different units and management bodies in the implementation of common current tasks and the implementation of promising cross-functional programs; 4) ensure an organic combination of vertical and horizontal management, bearing in mind finding the optimal ratio of centralization and decentralization with management for given conditions. All this requires a carefully developed step-by-step procedure for designing structures, detailed analysis and definition of a system of goals, thoughtful identification of organizational units and forms of their coordination.
Basic methodological principles of design
There are several definitions of the term “design”. Basically, they characterize it from two sides, as a generally accepted concept and from a scientific and technical position:
Design- the activity of a person or organization (s) to create a project, that is, a prototype, prototype of a proposed or possible object, state; a set of documentation intended for the creation of a certain object, its operation, repair and disposal, as well as for checking or reproducing intermediate and final solutions on the basis of which this object was developed.
From a concept specific to mechanical engineering, construction and other branches of science and technology "project"(English design) in the meaning of “design documentation” it is necessary to distinguish between those used in the field of activity project management in the context management concept "project"(English project, lat. projectus- thrown forward, protruding) in the meaning of “a certain task with certain initial data and required results (goals) that determine the method of its solution”, “program”, “set of work”, etc.
Design may include several stages from preparation of technical specifications to testing of prototypes. Design object is project material subject.
The concept of “design” does not include the project implementation stage.
Design has its own methodology, which includes structure activities, principles And norms activities, subjects,an object and him models,methods and etc.
Design methods
Main article: Design methods
Iteration method (successive approximation)
Decomposition method
Test question method
Brainstorming method
Theory of Inventive Problem Solving (TRIZ)
Method of morphological analysis
Functional cost analysis
Construction methods
Heuristic methods
Goals and types of experimental methods
Experiment planning
Machine experiment
Thought experiment
Experimental methods
Methods for searching for solution options
Methods for automating design procedures
Optimal Design Methods
Formalized methods
3 The process of forming an organizational structure
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Design
There are several definitions of the term “design”. Basically, they characterize it from two sides, as a generally accepted concept and from a scientific and technical position:
The concept of “design” does not include the project implementation stage.
Design has its own methodology, which includes structure activities, principles And norms activities, subjects, an object and him models, methods and etc.
Story
Drawing of door structures
Concept of construction
Within the design process, along with the calculation stages and experimental studies, the design process is often distinguished.
Construction- activity to create a material image of the object being developed; it is typical to work with full-scale models and their graphic images (drawings, sketches, computer models). These models and images, as well as some types of products, are called designs.
For example, designing clothing forms, designing interiors, developing a machine design, constructive and space-planning solutions for an object capital construction, metal structures, building structures.
The word “construction” is often used in the sense of “structure”, “device”, for example, the construction of a sentence in linguistics or the organization of aesthetic material in art.
Design can be carried out:
- Manually using drawing tools, for example, a drawing board (drawing table);
- Automated - using design automation systems (CAD);
- Automatic (without human intervention) using an Intelligent Information System (IIS).
Types of design
By industry
According to the types of objects being developed, the following types of project activities are distinguished:
By approach to design
Any object only serves material carrier functions, that is, the function is primary, the object is secondary and is created due to the impossibility of satisfying people’s needs by other, non-material means. Thus, a car is needed to transport goods and people (the function is to move in space, created due to the unreality of moving objects only by the effort of thought), the purpose of a pen is to write, and the purpose of books is to store information, etc.
Along with the word “function”, the word “purpose” is often used, especially when considering non-technical objects.
Functional design is aimed, first of all, at creating an efficiently operating facility. Performing the required function - the main objective and the basis for the development of the facility. First of all, functional quality indicators and reliability indicators are taken into account.
Functional design was the basis for the mass design of various objects, especially in the era of the USSR. When designing individually (individual buildings, consumer goods, etc.), the developer sought to take into account the wishes and characteristics of the customer.
The correct choice of function and priorities greatly influenced the final result. For example, the following joke is known from the 80s:
If we assume that the purpose of a car is to drive on roads, then its main part is the engine. Then we start developing the car with the engine, and place passengers in the remaining space. If we assume that the purpose of the car is to transport passengers, then we begin the development of the car from the interior, and place the engine in the remaining space. As a result, in the first case we get “Zaporozhets ZAZ-965”, in the second - “Volkswagen Beetle”.
Optimal design
The design process is always subject to the need to take into account the interests of two groups of people: producers and consumers of products (goods, works, services). Each group strives to satisfy its own product requirements, some of which may be mutually exclusive. Also, the process of solving a practical problem is always multivariate, and the developer is faced with the problem of reasoned choice of the final option.
For example, a car must not only have high speed and engine power, but also low cost, comfort, environmental friendliness, be profitable for the manufacturer, etc.
Design, the purpose of which is not only the search for functionally effective solutions, but also the satisfaction of different, sometimes conflicting needs of people, and an informed choice of the final option, began to be called optimal design (criteria design, variant design). It began to be actively used in the second half of the 20th century thanks to the achievements of decision-making theory and the theory of operations research and the widespread use of computer technology, which made it possible to develop appropriate methods, calculate numerous options and solve complex mathematical problems in a foreseeable time.
Great importance in optimal design is given to preparing at the technical specification stage a complete list of requirements for the object being developed, identifying quality indicators among them and converting the most important of them into optimization criteria. Indicative in this regard is the motto of one Japanese company - “We do not create technology, we create people.”
The structure establishes the stages of development of design documentation for products from all industries and the stages of work within each stage, that is, the composition of the documentation and types of work, which helps answer the question “What needs to be done?” during the design process. The main stages of the structure are shown in Figure 2 and include:
- Technical task(TOR) - establishes the main purpose of the object being developed, its technical and performance characteristics, quality indicators and technical and economic requirements, instructions for performing the necessary stages of creating documentation and its composition, as well as special requirements to the product.
- Technical Proposal(PT) - a set of documents containing a technical and feasibility study (feasibility study) of the feasibility of developing a project. This conclusion is given based on an analysis of the customer’s technical specifications and various options possible solutions, their comparative assessment taking into account the characteristics of the developed and existing products, as well as patent materials.
- Preliminary design(EP) - a set of documents containing fundamental decisions and giving a general idea of the structure and operating principle of the object being developed, as well as data defining its purpose, main parameters and overall dimensions. In case of great complexity of the object, this stage may be preceded by advance project(pre-design research), usually containing theoretical studies designed to substantiate the fundamental possibility and feasibility of creating a given object.
- Technical project(TP) - a set of documents that must contain the final technical solutions giving full view about the structure of the designed object, initial data for the development of working documentation.
- On detailed design stage(RP) first develop detailed documentation for the manufacture of a prototype and its subsequent testing. Tests are carried out in a number of stages (from factory to acceptance), based on the results of which the design documents are adjusted. Further develop working documentation for the production of the installation series, its testing, equipping the production process of the main components of the product. Based on the results of this stage, the design documents are again adjusted and working documentation is developed for the manufacture and testing of the lead (control) series. Based on documents that have been finalized and tested in production of products manufactured according to a fixed and fully equipped technological process, the final working documentation of established production is developed.
- The cycle of work is completed by the stage that sums up the project activities - certification. Its purpose is to determine the quality level of the created product and confirm its compliance with the requirements of those countries where its subsequent sale is expected. The need to distinguish this stage as an independent one is due to the fact that currently the export of products or their sale within the country in many cases is unacceptable without a quality certificate.
In the process of developing project documentation, depending on the complexity of the problem being solved, it is possible to combine a number of stages. The stages of setting technical specifications and technical design can be included in the cycle of scientific research work (R&D), and the stages of technical proposal and preliminary design can form a cycle of development work (R&D).
Design Process Structure
Fig.3. Process of solving a design problem
Design is also a purposeful activity that has a sequence of procedures leading to the achievement of effective solutions. Accordingly, there must be a structure for the process of solving a design problem that helps answer the question “How to do this?” Currently, a number of structures and design algorithms have been proposed that coincide in their main features and differ only in the content or name of individual stages. Figure 3 shows a generalized structure of this kind.
The solution to any problem begins with its comprehension and clarification of the initial data. Those (technical) requirements (TR) that are issued by the customer are formulated in the language of a non-specialist consumer and are not always technically clear and comprehensive. Translate the requirements into the language of the subject area, formulate the problem as completely and competently as possible, justify the need to solve it, that is, formulate a technical specification (TOR) - the first and mandatory stage work. The contractor performs it in close contact with the customer.
In mechanical engineering, this stage is sometimes called external design. This emphasizes that the development of an object already begins with the statement of the problem (TT) and the formation of technical specifications and is actively carried out jointly with the customer. An important result of the stage is the coordination of the development goals and purpose of the designed object (its functions), and a system of quality indicators.
The following stages form interior design. They are aimed at finding a solution to a problem and are carried out by the developer. This includes the stages of synthesis of the operating principle, structure and parameters of the designed object:
- At the stage of synthesis of the operating principle, fundamental provisions, physical, social, etc. effects are found that will form the basis for the functioning of the future product. These may be fundamental rules fundamental laws and rules, their special cases or consequences. The work is carried out with basic models and their graphical representation - block diagrams. This stage corresponds to the final stage of the technical specifications and the stage of the technical proposal of the design structure in accordance with GOST 2.103;
- At the stage of structural synthesis, based on the selected operating principle, options for the initial graphical representation of the object are created - structures, diagrams, algorithms, simplified sketches. In accordance with GOST 2.103, this stage includes the preliminary design stage;
- At the stage of parametric synthesis, the values of the object’s parameters are found, a numerical, including optimal, solution to the design problem is found, detailed documentation or description of the object, drawings of the product and its parts are created. This stage corresponds to the technical and detailed design stages.
Due to the incompleteness of initial knowledge about the problem, the design process is iterative, which is reflected in Figure 3 by the arrows of reverse movements. With each iteration cycle, the design goals become more and more refined, the need for additional functions appears and, as a result, the need to develop additional parts and assemblies. The solution of particular design problems that complement the main solution is also carried out in accordance with the presented sequence.
At each stage of internal design, the following procedures are performed:
- model selection (i.e. fundamental principle, type of block diagram and design diagram),
- choosing a solution method, including an optimization method,
- solution,
- analysis of the results obtained and decision making.
It is noted that the effectiveness of the designed object is determined: first of all, by the selected operating principle, secondly, by the proposed structure, and thirdly, by the ratio of parameters.
Design methods
Main article: Design methods
- Heuristic methods
- Iteration method (successive approximation)
- Decomposition method
- Test question method
- Brainstorming method
- Theory of Inventive Problem Solving (TRIZ)
- Method of morphological analysis
- Functional cost analysis
- Construction methods
- Experimental methods
- Goals and types of experimental methods
- Machine experiment
- Thought experiment
- Formalized methods
- Methods for searching for solution options
- Methods for automating design procedures
- Optimal Design Methods
Participants (subjects) of design work
Design is one of the types of work, the result of which is a product-project. Therefore, the participants in these works can be divided into consumers ( customers design work) and suppliers ( performers these works). A specialist in project development is generally called a designer or developer. If the product is created for one’s own consumption, then it is possible to combine the customer and the contractor in one person.
The supplier, like the consumer, of products can be an organization (legal entity) or a specific person (individual). Work on the creation of such products in accordance with Civil Code are classified as contractors. In this situation, the performer is called a contractor, that is, a party to a work contract who undertakes to perform certain work on the instructions of the other party (customer) and deliver the result to the customer, and the customer undertakes to accept the result of the work and pay for it. The contractor is considered as the first party in commercial activities. Subcontractor - an organization that represents products to a supplier.
There is another participant in this work - the state, which has created a system of measures to protect consumers through control, licensing, and the issuance of regulatory documentation, including regulating project activities.
The creation of automated information systems and technologies in the economy can be carried out according to two options. The first option assumes that this work is carried out by specialized firms with professional experience in preparing software products of a specific orientation. According to the second option, the design and creation of developments is carried out by designers and programmers who are on staff at enterprises where new information technologies and systems are created.
As designers develop automated systems, workplaces, and technologies, they face a number of interrelated challenges.
It is difficult for a designer to obtain comprehensive information to assess the requirements formulated by the customer (user) for a new system or technology.
The customer often does not have sufficient knowledge about automation problems to judge the possibility of implementing certain innovations. At the same time, the designer is faced with an excessive amount of detailed information about the problem area, which causes difficulties in modeling and formalizing the description of information processes and solving functional problems.
The specification of the designed system, due to its large volume and technical terms, is often incomprehensible to the customer, and its excessive simplification cannot satisfy the specialists creating the system.
With the help of well-known analytical methods, some of the listed problems can be resolved, but a radical solution is provided only by modern structural methods, among which the methodology of structural analysis occupies a central place.
Structural analysis usually called a method of studying a system that begins with a general overview of it and then goes into detail, acquiring a hierarchical structure with an increasing number of levels. Structural analysis involves dividing the system into levels of abstraction with a limited number of elements at each level (usually from 3 to 6-7). At each level, only the details essential to the system are highlighted.
The methodology of structural analysis is based on a number of principles. The two basic principles are the principle of decomposition and the principle of hierarchical ordering. First principle involves solving difficult ones by breaking them down into easy tasks for understanding and solutions. Second principle declares that the system can be understood and built in levels, each of which adds new details.
At the pre-design stage, a study and analysis of all the features of the design object is carried out in order to clarify the customer’s requirements. In particular, a set of conditions under which it is expected to operate the future system is identified (hardware and software resources; external conditions of its functioning; the composition of people and works related to it and participating in information and management processes), a description of the functions performed by the system is made, etc. P.
At this stage the following are determined:
system architecture, its functions, external conditions, distribution of functions between hardware and software;
interfaces and distribution of functions between a person and the system;
requirements for software and information components of the system, necessary hardware resources, database requirements, physical characteristics system components, their interfaces.
The quality of further design depends decisively on the correct choice of analysis methods and the formulated requirements for the newly created technology.
The methods used at the pre-project survey stage are divided into: methods for studying and analyzing the actual state of an object (technology), methods for forming a given state, methods of graphical representation of actual and specified states). Let's look at these methods in more detail.
Methods for studying and analyzing the actual state of an economic object or technology. These methods allow you to identify bottlenecks in the processes under study and include: oral or written survey; written survey; observation, measurement and evaluation; group discussion; task analysis; analysis of production and management processes.
In general, methods for studying and analyzing the actual state of management activities and existing technology for solving problems are intended to collect the necessary materials and form the basis for the design of AIS and AIT.
Methods for forming a given state . They are based on the justification of all components of the AIS based on the goals, requirements and conditions of the customer. These methods, which are working tools for designers, include the following methods: modeling the management process; structural design; decomposition; information process analysis.
Method for modeling the management process. In the process of studying the design object, economic-organizational and information-logical models are built. They reflect economic and management relations, as well as information flows associated with them.
Structural Design Method allows you to divide the entire complex of tasks into observable and analyzable subcomplexes (modules).
Decomposition method modules provides for further division of subcomplexes of tasks into separate tasks and indicators.
Analysis of information processes designed to identify and represent the relationship between the result, the processing process and data input. It is also used to analyze and form information links between the workplaces of management workers, specialists, technical personnel and information technology. For this purpose, input and output information is described, as well as an information processing algorithm in relation to each workplace.
Methods for graphical representation of actual and set states involve the use of a visual representation of information processing processes. The most famous of them include the flowchart method, methods of arrow diagrams, network diagrams, tables of the sequence of operations of processes.
If at the pre-design stage the requirements for the creation of AIS and AIT should be formulated in the technical specifications, then the design should answer the question: “How will the system satisfy the requirements placed on it?”
As a result of the design stages, a system design should be obtained within the budget of the allocated resources.
The design stages include the following main work: development of goals and organizational principles of AIS; formation of a version of AIS and AIT; debugging programs; trial operation and delivery of the AIS and AIT project.
In the process of organizing the design, various decisions are made that affect the dynamics and quality of work. Therefore, for each design stage the following are determined: expected results and documents; personal functions of the manager; decisions made by the manager; functions of the customer and developer of AIS and AIT.
The design and executive documentation includes: instructions for work processes, programs for workplaces, instructions for preparing documents, recommendations for the use of information, methods, decision tables, etc.
In modern conditions, AIS, AIT and automated workplaces, as a rule, are not created from scratch. In the economy, automated information processing systems operate at almost all levels of management and at all economic entities - from regional government bodies, financial and credit organizations, enterprises, firms to trade organizations and service sectors. However, the need for timely, high-quality, operational information and its assessment as the most important resource in management processes, as well as the latest achievements of scientific and technological progress, necessitate the restructuring of functioning automated information systems in the economy, the creation of AIS and AIT on new technical and technological bases.