What is the model of a boxer? A straight angle is 180 degrees, which is a straight line.
A model is an entity. In real life, there can be many flat-angle objects instead of understanding, such as a pen and a plane, as long as it is 180 degrees.
What kind of model is the airplane model? An airplane model refers to a static airplane model (different from a model airplane).
It can be a reduced appearance model of the real machine.
You can also create your own conceptual machine model.
What kind of model is a mathematical model? The history of mathematical models can be traced back to the time when humans began to use numbers. With the application of numbers, various mathematical models are constantly established to solve various practical problems. A mathematical model can be established to establish an optimal scheme for daily activities such as college students' comprehensive quality evaluation, teachers' work performance evaluation, and visiting friends and purchasing. The establishment of mathematical model is an indispensable bridge between practical problems and mathematical tools.
1, true and complete.
1) is true, systematic and complete, and the image reflects the objective phenomenon;
2) It must be representative;
3) Extrapolation, that is, the information of the prototype object can be obtained, and the reasons about the prototype object can be obtained in the process of model research and experiment;
4) It must reflect the various achievements made in completing the basic tasks and should be consistent with the actual situation.
2. Concise and practical. In the process of modeling, we should reflect the essential things and their relationships, and eliminate the non-essential things that have little influence on reflecting the objective truth, so that the model can be as simple and operable as possible and the data can be easily collected while ensuring a certain accuracy.
3. adapt to change. With the change of related conditions and the development of people's understanding, we can adapt to the new situation well by adjusting related variables and arguments.
According to the research purpose, a structure (called real prototype or prototype) that generalizes and approximately expresses the main characteristics and relations of the processes and phenomena studied by formal mathematical language. The so-called "mathematization" refers to the construction of mathematical models. The method of understanding things by studying their mathematical models is called mathematical model method, or MM method for short.
Mathematical model is the product of mathematical abstraction, and its prototype can be concrete objects and their properties and relationships, or mathematical objects and their properties and relationships. Mathematical models can be divided into broad sense and narrow sense. In a broad sense, mathematical concepts, numbers, sets, vectors and equations can all be called mathematical models. In a narrow sense, mathematical models can be roughly divided into two categories: (1) deterministic models that describe the inevitable phenomena of objects, and their mathematical tools are generally algebraic equations, differential equations, integral equations and difference equations; (2) mathematical models of excellent athletes are often mentioned in sports practice. According to investigation and statistics, the model of modern world-class sprinters is about 1.80m in height and 70kg in weight, 100 Mi Yue 100 seconds or better.
An equation or inequality composed of mathematical symbols such as letters and numbers, or a model that describes the characteristics of the system and its internal communication or communication with the outside world with charts, images, block diagrams, mathematical logic, etc. It is an abstraction of a real system. Mathematical model is a powerful tool to study and master the law of system motion, and it is the basis for analyzing, designing, predicting or controlling the actual system. There are many mathematical models and different classification methods.
Static model and dynamic model Static model means that the relationship between variables of the system to be described does not change with time, and is generally expressed by algebraic equations. Dynamic model refers to a mathematical expression that describes the laws of system variables changing with time, and is generally expressed by differential equations or difference equations. The transfer function of the system commonly used in classical control theory is also a dynamic model, because it is transformed from the differential equation describing the system (see Laplace transform).
Distributed independent variable model and centralized independent variable model describe the dynamic characteristics of the system with various partial differential equations, while centralized independent variable model describes the dynamic characteristics of the system with linear or nonlinear ordinary differential equations. In many cases, the distributed argumentation model can be simplified to a centralized argumentation model with low complexity through spatial discretization.
Continuous-time models and discrete-time models with time variables varying in a certain interval are called continuous-time models, and the above models described by differential equations are all continuous-time models. When dealing with lumped parameter model, time variables can also be discretized, and the obtained model is called discrete time model. The discrete-time model is described by the difference equation.
The relationship between randomness and variables in deterministic model is given in the form of statistical value or probability distribution, while the relationship between variables in deterministic model is deterministic.
Independent variable and non-independent variable models The models described by algebraic equations, differential equations, differential equations and transfer functions are all independent variable models. Establishing an independent variable model is to determine each independent variable in the known model structure. Demonstration models are always obtained through theoretical analysis. The uncontroversial model is a response obtained directly or indirectly from the experimental analysis of the actual system. For example, the impulse response or step response of the system recorded by experiments is a model without independent variables. Using various system identification methods, the variable model can be obtained from the invariant model. If the structure of the system can be determined before the experiment, the demonstration model can be directly obtained through experimental identification.
The relationship between variables in linear and nonlinear models is linear, and the superposition principle can be applied, that is, several different inputs act on the response of the system at the same time, which is equal to the sum of the responses of several inputs acting alone. The linear model is simple and widely used. The relationship between quantities in the nonlinear model is not linear and does not satisfy the superposition principle. When allowed, nonlinear models can usually be linearized into linear models. The method is to expand the nonlinear model into Taylor series near the working point, keep the first-order term and omit the higher-order term, and then the approximate linear model can be obtained.
Edit the definition of the mathematical model in this paragraph. At present, there is no unified and accurate definition of mathematical model, because there can be different definitions from different angles. But we can give the following definition. "A mathematical model is an abstract and simplified structure about a part of the real world, used for special purposes." Specifically, a mathematical model is an equation or inequality established by mathematical symbols such as letters and numbers for a certain purpose, as well as a mathematical structure expression that describes the characteristics of objective things and their internal relations, such as charts, images, block diagrams, etc.
What kind of model tree looks good? Pine! Indoor potted plants.
Satisfied, please adopt.
What kind of model plane? Hello, I'm glad to answer your questions.
We are Fei Ying Le Jia Model Electric Tune, welcome to experience. Whether the model airplane is good or not depends on whether it suits you. Generally, novices start with anti-fall models such as aircraft and good boys, and the cost is not high, and then slowly develop in the direction of aerial photography! I hope it helps you.
What is the model system behind Zhenrongbao? The model system behind Zhenrong Baobei can analyze users' consumption patterns and daily capital inflows, establish decision-making basis from the multi-dimensional characteristics of users' assets, income and risk tolerance, and allocate appropriate investment portfolios accordingly. According to reports, at present, Zhenrongbao has been able to carry out user portraits through 7 dimensions, 3 0 industries and tens of millions of sub-tags. On this basis, we can provide customized services based on investment targets for individual customers.
What is the model of the gun god Shiva Agatha? The prototype is Christmas milk-Youni
What is the model of 1 spin in quantum mechanics? 1/2 spin means that the spin has two states of "up" and "down", and then the particles rotate 720 degrees symmetrically. . . .
What is the concept of talent? Connotation analysis of talent concept
First, the existing definition of talent
What is talent? The following is the definition of representativeness:
1. The definition of "talent" in the newly edited Ci Hai is: a person with talent and knowledge, a person with both ability and political integrity.
2. Wang Tongxin said: "Talents refer to people who can make great contributions to social development and human progress with their creative labor under certain social conditions."
3. Ye Zhonghai said: "Talents refer to people who have certain professional knowledge, high technology and ability in various social practice activities and can make some significant contributions to understanding and transforming nature and society and human progress through their own creative work."
4. Talents refer to people who have made creative work for social development and human progress and made great contributions in a certain field, industry or job.
5. Guo Yu pointed out in "On Talents" that talents are "people who creatively apply their subjective wisdom to practice and achieve fruitful results".
6. Wang Peng said in "The Way of Employing People": "Talents include mental workers and manual workers; There are people with academic diplomas, and there are people without academic diplomas. As long as they have rich knowledge and high skills and contribute to social progress, they can all become talents. "
7. Liu Shengen pointed out in "A Concise Course for Talents": "Talents are people who work creatively in the process of understanding and transforming the world under certain social and historical conditions. ..... Historicity is the premise of talent formation. Anyone is a talent whose society has developed to a certain stage under specific historical conditions. Without society and history, there is no talent. Practicality is the foundation and an important necessary condition for talents. Talent is a talent in practice, and there is no talent without practice. Creativity is the core and the most fundamental feature of talents. The boundary between talents and non-talents lies in whether creative labor can be carried out. "
8. Professor Huang of capital university of economics and business expounded the concept of talents from an academic point of view: "Talents refer to people who have extraordinary knowledge, skills and will that are valuable to society and can make great contributions under certain social conditions. Talents include not only intellectuals with extraordinary knowledge, but also craftsmen, artists and' leaders' with extraordinary skills and' heroes' with extraordinary will. Simply put, it is a high-quality person that society needs. "
9. There are levels of talents and excellent talents. It is talents who make great contributions to society. Many skilled workers who have no college education but have rich practical experience and considerable management level are also talents. (People's Daily, September 22nd 1986, skilled workers are talents).
Although the above definitions are different, they reveal the attributes of talents from different angles. In summary, they mainly emphasize the following aspects:
1. Epoch and sociality. In other words, talents are talents under certain social and historical conditions, and there is no talent without social history.
2. The superiority of internal quality. It is believed that talents have better quality than ordinary people, and it is difficult to become talents without higher quality.
3. Social practicability. It is emphasized that practice makes talents, and the labor achievements of talents must also be tested by practice.
4. Universality and diversity. In other words, there are not only "top scholars", but also talents in posts with different labor properties.
5. Creativity of labor achievements. It is creative to emphasize that the labor of talents is different from the imitation and repetition of ordinary people.
6. Extraordinary contribution. Because the labor results of talents are often creative, the contribution of talents is far greater than that of ordinary people.
7. Differences in ability. In other words, talents in different industries have their own strengths, and talents in the same industry also have their own strengths.
8. The role of progress. It is believed that people can transform nature and society through their own creative activities, thus promoting the development and progress of human society.
Second, the essential attributes of talents
According to logic, a concept is a thinking form that the human brain reflects the essential attributes of things. The so-called definition is to reveal the essential attributes of the objective things reflected by the concept, so as to distinguish it from its adjacent concepts and avoid conceptual ambiguity and ideological confusion. The traditional definition method in logic is to add "species difference" to adjacent "genera" to define concepts. Expressed by formula, the concept of definition is two kinds of ten adjacent generic concepts. By defining concepts, the most important thing is to determine species differences.
Talent, as a concept, its subordinate concept is people, and its adjacent concept is ordinary people or ordinary people. In front of us, we analyzed the eight attributes of the concept of "talent" by scholars. So, what are the essential attributes and non-essential attributes of "talent"? From this we can grasp the essence of the concept of "talent".
1. Epoch and sociality. Talents are historical and social, and talents in different times and societies have different connotations. Due to the constraints of historical and social conditions, the play and scope of talents' role will also be limited to varying degrees. People in the past can't do what they do now, and people in the present age can't do what they did in the past. There is no doubt about it. So, do ordinary people have social and historical times? The answer is yes. Marxism holds that "the masses of the people are a historical concept. In different countries, each country has different connotations in different historical periods. " Talent, as an important part of people, certainly has this attribute. Secondly, talents and ordinary people * * * together constitute the human society, which has social historicity, and ordinary people certainly have social historicity. Talents are social historic, and so are ordinary people. Besides, are we ordinary people still the same as before? Can ancient people have the pioneering work now? Therefore, the times and sociality are not the essential attributes of talents.
2. The superiority of internal quality. Generally speaking, talents have superior qualities that ordinary people do not have in one or several aspects. The quality here is broad, beyond our general sense of virtue. Intellectual, physical, aesthetic, labor and other categories. It includes many aspects such as high education, noble morality, sleepless nights, extraordinary intelligence, incomparable courage, eloquence, extraordinary strategy and so on. These are not possessed by ordinary people, so the superiority of internal quality is one of the essential attributes of talents.
3. Social practicability. The classical theory of Marxism holds that human beings are different from other animals because they can think and work. In this case, talents and ordinary people, as two concepts of human beings, also have this attribute. Talents need to participate in social practice, increase their perceptual knowledge and accept the test of practice, while the general public must also participate in social practice activities and obtain survival and development materials from labor. Therefore, social practicality is not the essential attribute of talents.
4. Universality and diversity. Indeed, talents are universal and diverse. Everyone has his specialty. However, God has also endowed ordinary people with this attribute. Where there are talents, there are ordinary people, and without expertise, they become ordinary people.
5. Creativity of labor achievements. Creativity here is also a broad concept, including both material and spiritual aspects. In short, it is the breakthrough and innovation that all walks of life surpass their predecessors, contemporaries or most people in a certain area. According to its nature, human labor can be divided into imitation labor, repetitive labor and creative labor. The first two kinds of labor are characterized by inherited labor, and the result is only to repeat the labor forms and experiences created by predecessors, so there can be no great harvest of labor results. The labor of ordinary people belongs to the first two kinds. Talents, on the other hand, have superior internal qualities, which determines that they can and are willing to make innovations and breakthroughs on the basis of predecessors' experience and achievements. Their work is mainly creative work. Therefore, the creativity of labor achievements is an important essential attribute of talents.
6. Extraordinary contribution. The creativity of talents determines that they can achieve greater achievements than their predecessors and surpass the achievements of ordinary people, so the contribution of talents is far greater than that of ordinary people. It is precisely because of this that rulers at all times and all over the world attach great importance to talents and do everything possible to attract and use talents in order to safeguard the rule of their own class. Obviously, this is also one of the essential attributes of talents.
7. Differences in ability. Of course, the ability of talents is different. Talents in different industries have their own specialties, and the level of talents in the same industry is also uneven. Especially in today's increasingly high technology content, there is a saying that interlacing is like a mountain. However, who can deny the great differences between ordinary people? Workers can't farm and farmers can't work. Farmers in the north can't grow rice, and farmers in the south can't grow millet. Most people in China can't speak foreign languages, and many foreigners can't speak Chinese. This is obvious. Therefore, this is not the essential attribute of talents.
8. The role of progress. The energy of talents is enormous, which can play a great role in transforming nature and promoting social progress and development. But can we think that ordinary people can't play a driving role? Otherwise, dialectical materialism holds that the masses of the people are the force to push history forward and the masses have created history. Of course, we can't deny the driving force of ordinary people, although the main force is talent. Therefore, the role of progress is not the essential attribute of talents.
After analysis and demonstration, it is not difficult to find that among the above attributes, only the superiority of internal quality, the creativity and extraordinary contribution of labor achievements are the "species differences" between "talents" and "ordinary people", that is, the essential attributes, and the others are non-essential attributes. According to the definition principle of logic, only by excluding non-essential attributes can we correctly define the concept of "talent" reflecting essential attributes.
Now, let's see if we have exhausted the essential attributes of talent. If we consider the distribution of quantity, we can easily find that talents are scarce. The ancients said: talent is hard to find. Not only does the growth of talents need a hard process, but also more efforts. Even if a lot of efforts are made, it may not be successful. This determines that compared with the average person, talents are born as a "minority". The pupil outdoes the master. Talents are produced among the broad masses of the people, but they are just a few bright stars in the sky. Therefore, scarcity is the essential attribute of talents.
Third, the connotation of the concept of talent
Now, we can apply the formula defined below to give the scientific concept of "talent".
Talents are a few people with superior internal quality who have made extraordinary contributions to the fruits of creative labor. Grasping these four attributes, we can scientifically judge which talents are and which are not.
This concept has the following characteristics:
1. Grasp the essence of talents. No education. Identity, age, status, industry, etc.
2. In terms of quantity, creative labor results are more than non-creative labor results. Most people are more or less creative, and the uniqueness of talents lies in creativity.
3. Emphasize the development of talents. Talents are developing and changing. Ordinary people can become talents, and talents can also become ordinary people. The "talents" used by competitors are used by me and become talents.
This concept can at least solve many problems that cannot be solved by many definitions at present. First of all, is the influential villain a talent? "Villains" are certainly not talents. Although most of them have some essential attributes of talents, they do not have the essential attributes of extraordinary contributions. Nowadays, the word "contribution" is generally interpreted as something beneficial to the country or the public, which is a commendatory term. Therefore, the role of villains can never be measured by the word "contribution". Of course, because talents can be changed, it is not denied that ordinary people can become talents, negative people become positive people, and then become talents, and talents become ordinary people or even negative people.
Secondly, are college students talents? We can't generalize. College students are a special group with good quality and creative conditions. However, because most of them have no creative work or are mainly not creative work, they have not made extraordinary contributions and have not exerted their potential. So for most college students, they are not "talents" in the strict sense, but can only be called "potential talents". Of course, it doesn't rule out that a few college students have exerted great potential and made extraordinary contributions with their creativity. Of course they are talented people.
In short, to grasp the concept of "talent" scientifically, it is necessary to scientifically clarify the essential and non-essential attributes of talents and not mix them indiscriminately, otherwise the concept obtained is unscientific and imprecise. This will help us deeply understand the scientific connotation of talents, help us objectively discover talents, develop talent resources and improve the effective utilization of talent resources. Of course, this concept belongs to the qualitative concept, which can not exhaust the superior internal quality, nor can it clearly identify what is extraordinary contribution, so we need to grasp it carefully in practice.