A class of models described in mathematical language. A mathematical model can be one or a set of algebraic, differential, difference, integral, or statistical equations, or some appropriate combination of them, by which the interrelationships or causal relationships among the variables of a system are described quantitatively or qualitatively. In addition to mathematical models described by equations, there are also models described by other mathematical tools, such as algebra, geometry, topology, mathematical logic, etc. It should be noted that mathematical models describe the behavior and characteristics of the system rather than the actual structure of the system.
Physical models
Aeronautical models
Also known as physical model, it can be further divided into physical model and analogous model.
①Physical model: a physical object manufactured according to the similarity theory that is scaled down (or can be enlarged or the same size as the original system) according to the original system, such as an aircraft model in a wind tunnel experiment, an experimental model of a hydraulic system, an architectural model, a ship model, etc.
Space model
② Analogous model: In different physical fields (mechanical, electrical, thermal, hydrodynamic, etc.) of the system of the respective variables sometimes obey the same law, according to this common law can make a physical meaning of completely different analogous and analogous models. For example, the pressure response of a pneumatic system consisting of a throttle valve and an air volume under certain conditions has a similar law to the output voltage characteristics of a circuit consisting of a resistor and a capacitor, so it is possible to simulate a pneumatic system with a circuit that is easier to experiment with.
Structural model
A model that mainly reflects the structural characteristics and cause-effect relationships of a system. An important class of structural models is the graphical model. In addition, the room model (see room model identification), which is commonly used in biological system analysis, is also a structural model. Structural models are effective tools for studying complex systems.
Industrial models
Computer models
Definition: Industrial model, commonly known as hand board, first board model and rapid prototyping, the main production methods are CNC machining, laser rapid prototyping and silicone mold small batch production. Industrial models are widely used in the R&D stage of new industrial product design to process a physical model consistent with the design in the shortest possible time. The designers can confirm the appearance of the product and test the function, so as to improve the design, reduce the development cost, shorten the development cycle and get the customer's approval quickly.
Application scope.
Digital products (cell phones, telephones, USB. headphones, cameras)
Home appliance medical products (TV, computer, air conditioner, vacuum cleaner, printer, copier, washing machine, kettle, massager, ultrasound instrument)
3. Auto parts (car dashboard, car door, car air conditioner, car DVD car light, reverse disc, bumper).
Today's industrial model is not as simple as hand board, it has been transformed from digital products, home medical products and auto parts to large scale mechanical and engineering models. It is even larger than the scale of architectural models, and the craft difficulty factor is further increased.
Simulation Model
Nautical model
A model expressed by a program running on a digital computer, an analog computer or a hybrid computer. Using an appropriate simulation language or program, physical, mathematical and structural models can generally be transformed into simulation models. Regarding the effect of different control strategies or design variables on the system, or the possible effects of certain perturbations on the system, experiments on the system itself are preferable, but this is not always possible. There are various reasons for this, such as: experiments can be expensive; the system may be unstable and experiments may upset the equilibrium of the system and cause danger; the time constants of the system are large and experiments take a long time; the system to be designed does not yet exist, etc. In such a case, it is effective to build a simulation model of the system. For example, the methanation process of organisms is an anaerobic fermentation process that produces methane due to the decomposition of bacteria. Based on the knowledge of biochemistry it is possible to build a simulation model of the process, to find the optimal steady-state value of the process by computer and to study various start-up methods. These studies are almost impossible to do on the system itself, because it is technically difficult to keep the process at steady state and the start-up process of biomethanation reactions is slow and takes several weeks. However, if the methanation reaction is simulated on a computer using a (simulation) model, the start-up process of the methanation reaction takes only a few minutes.
Digital model, also known as digital sandbox, multimedia sandbox, digital sandbox system, etc., is modeled in three dimensions to simulate a three-dimensional building, scene, and effect, which can be wandered, galloped, flown, and scaled at will in the digital scene, from the whole to the local and then from the local to the whole, without any limitation. With three-dimensional digital technology to build a three-dimensional digital city, virtual model room, traffic and bridge simulation, garden planning three-dimensional visualization, three-dimensional simulation of ancient buildings, mechanical industrial equipment simulation demonstration with the help of PC, display system, etc. to play a role in display, interpretation, command, explanation. Multimedia sand table is the use of projection equipment combined with physical planning model, through precise alignment, the production of dynamic plane animation, and projected onto the physical sand table, thus producing dynamic changes in the form of new physical model performance.
Digital model through sound, light, electricity, images, three-dimensional animation and computer program control technology and the integration of the physical model, can fully reflect the characteristics of the display content, to achieve a unique, dynamic visual effect of change. It is a new experience for visitors and can produce strong resonance. Digital model is a new concept proposed by Shenzhen Saino Model, the largest and earliest model design and production company in China. Its self-developed digital simulation technology has obtained national patent and has been reflected in its Shaoguan planning hall and Shaoguan city overall planning project. The new term of digital model will replace the traditional architectural model in the near future and become another new highlight of the display content. Digital model transcends the monotonous physical model sand table display method, based on the traditional sand table, adding multimedia automation program, fully expressing the characteristics of the district, the four seasons change and other rich dynamic visual effects. It is a new experience for customers and can produce a strong sense of visual shock. Customers can also choose to watch the corresponding display content through the touch screen, which is simple and convenient and greatly improves the interactive effect of the whole display.
Human Resource Model
There are various resources used by enterprises, but "all material factors can only be developed and utilized through the human factor", therefore, "human" is the most valuable resource, which has been generally recognized. Based on such a consensus, people have realized that "the essence of management is to manage people", thus, people-centered management has become the common development trend of modern management, and human resource management has become the core content of enterprise management.
The first is the internal force, that is, the workers themselves have the ability and internal drive to create value for the enterprise.
The second is the pulling force, which is to pull and guide employees to work hard and improve their ability with direction and goal, equivalent to someone pulling him forward in front. The implementation of the pull, mainly by the traction mechanism, the core is the corporate culture system and training and development system, in addition to job descriptions, qualification standards, career system, etc..
The third is the control force, which is to supervise and check the degree of employee effort, the effect of work, restrain the path forward and correct the direction of the employee. It is equivalent to someone on the side to supervise and guide him forward. The implementation of control, mainly by the restraint mechanism, the core is the performance appraisal system, in addition to the code of conduct for employees, qualification system, etc.
The fourth is pressure. It is to pressure and spur employees, eliminating poor performance, difficult to improve the ability or subjective work of employees who do not work hard. The implementation of pressure, mainly by the competition elimination mechanism, the core is the last elimination system and competition on the system, in addition to the personnel exit system, ability quality assessment.
The fifth is the push, is to promote and motivate employees to continuously improve their ability to work hard, equivalent to someone behind to push him forward. The implementation of the thrust mainly relies on the incentive mechanism, the core of which is the setting of the salary incentive system, in addition to the authorization settings, career management, etc.
Thinking Model
Expressing people's thinking and problem-solving forms in easy-to-understand graphics, symbols, structured language, etc. is collectively known as thinking models.
