Äèïëîìíàÿ ðàáîòà: The manager as a teacher: selected aspects of stimulation of scientsfsc thinking
Stabilization systems and proportional systems. There exist a great number of types of various systems. But stabilization systems and proportional systems are of special importance for us. In respect of the first one the result of action always remains the same (stable), it does not depend on the force of external influence, but on the command. For example, ðÍ of blood should be always equal to 7.4, blood pressure to 120/80 mm Hg, etc., (homeostasis systems) regardless of external influences. In respect of the second one the result of action depends on the force of external influence under any specific law designated by the command and is proportional to it. For example, the more physical work we perform the more Î2 we should consume and excrete ÑÎ2. Stabilization system uses two receptors, “Õ” and “Y”. The “Õ” receptor is used to start up the system depending on the presence of external influence, while the “Y” receptor is used for the measurement of the result of action. The command (the task specifying the value of the result of action) is entered to the command entry point of the stabilization system’s control block. Stabilization system should fulfill this task, i.e. support (stabilize) the result of action at the designated level irrespective of the force of external influence. Stability of the result of action is ensured by that the “database of the control block contains the ratios/correlations of the number of active SFU and forces of external influence and is sustained according to the NF logic: if the result of action has increased, it is necessary to reduce it, and if it has decreased it’s necessary to increase it. For this purpose the control block should contain DPC and NF. Hence, the elementary control block (DPC) is not suitable for stabilization systems. At least simple control block which contains NF as well is necessary. In stabilization system the result of action of the system up to vertical dotted straight line is stable (normal function, the curve goes horizontally). Beyond the dotted straight line the function goes down (increases), stabilization was disturbed (insufficiency of function). With proportional system, its function increases (goes down) until vertical dotted straight line proportionally to the external influence (normal function). Beyond the dotted straight line the function does not vary (it entered the saturation phase, transited to a plateau condition - insufficient function). The measuring element in stabilization system continually measures the result of action of the system and communicates it to the control block which compares it to the preset result. In case of discrepancy of the result of action with the task this block makes decision on those or other actions to be taken and forces the executive elements to operate so that this divergence has disappeared. External influence may vary within various ranges, but the result of action should remain stable and be equal to the preset result. The system spends its resources to do it. If the resources are exhausted, stabilization system ceases to stabilize the result of action and starting from this point the onset of its insufficiency occurs. One of stabilization examples is stellar rotation speed in vacuum. If the radius of the star reduces, its rotational speed will increase and centrifugal forces will amplify, thus scaling up its radius and slowing down its rotational speed. If the radius of the star scales up, the entire process will go in a reverse order. A figure skater regulates the speed of rotational pirouettes he/she performs on the skating-rink based on the same principle. Proportional system should also use both “Õ” and “Y receptors. One of them measures the incoming influence, while another one measures the result of action of the system. The command (the task as to what the proportion between external influence and the result of action should be) is input to the entry point of the control block. It is for this reason that such systems are called proportional. External influence may change within the varying range. But the control block should adjust the performance of the executive elements so that the “prescribed” (preset by the directive) proportion between external influence and the result of action is maintained. Examples of proportional systems are, for example, amplifiers of electric signals, mechanical levers, sea currents (the more the water in the ocean is warmed up, the more intensive is the flow in the Gulf Stream), atmospheric phenomena, etc. So, the examples of stabilization and proportional systems are found in any medium, but not only in biological systems.
Active and passive systems. Passive systems are those which do not exspend energy for their actions. Active systems are those which do exspend energy for their actions. However, as it was repeatedly underlined, any action of any system requires expenditure of energy. Any action, even the most insignificant, is impossible without expenditure of energy, because, as it has already been mentioned, any action is always the interaction between systems or its elements. Any interaction represents communication between the systems or their elements which requires expenditure of energy for the creation thereof. Therefore any action requires energy consumption. Hence, all systems, including passive, consume energy. The difference between active and passive systems is only in the source of energy. How does the passive system operate then? If the system is in the state of equilibrium with the environment and no influence is exerted upon it the system should not perform any actions. Once it does not perform any actions, it does not consume energy. It is passive until the moment it starts to operate and only then it will start to consume energy. The balanced state of a pencil is stipulated by the balanced pushing (pressure) of springs onto a pencil. The springs are not simply incidental groups of elements (a set of atoms and molecules), but they are passive systems with NF loops and executive elements at molecular level (intermolecular forces in steel springs) which seek to balance forces of intermolecular connections/bonds which is manifested in the form of tension load of the springs. Since in case of the absence of external influence no actions are performed by the system, there is no energy consumption either, and the system passively waits for the onset of external influence. Both types of systems have one and the same goal: to keep a pencil in vertical position. In passive systems this function is carried out by springs (passive SFU, A and B) and air columns encapsulated/encased in rubber cans (passive SFU, D). The SFU store (use) energy during external influence (pushing a pencil with a finger squeezes the springs). In active system (C) the same function is achieved for at the expense of airflows which always collapse. These airflows create motor fans (active SFU) which spend energy earlier reserved, for example, in accumulators. Once these airflows are encapsulated/encased in rubber cylinders they will not collapse any more and will exist irrespective of fans, while carrying out the same function. But now it represents a passive system (D). Now external influence occurs and the pencil has diverged aside. The springs would immediately seek to return a pencil to the former position, i.e. the system starts to operate. Where does it take energy for the actions from? This energy was brought by the external influence in the form of kinetic energy of pushing by a finger which has compressed (stretched) the springs and they have reserved this energy in the form of potential energy of compression (stretching). As soon as external influence (pushing by a finger) has ceased, potential energy of the compressed springs turns to kinetic energy of straightening thereof and it returns a pencil back in the vertical balanced position. External influence enhances internal energy of the system which is used for the performance of the system. The influence causes surplus of internal energy of the system which results in the reciprocal action of the system. In the absence of influence no surplus of the system’s internal energy is available which results in the absence of action. External influence brings in the energy in the system which is used to produce reaction to this influence. Functions of springs may be performed by airflows created by fans located on a pencil. In order to “build” airflows surplus of energy of the “fans – pencil” system is used which is also brought in from the outside, but stored for use at the right time (for example, gasoline in the tank or electricity in accumulator). Such system would be active because it will use its internal energy, rather than that of external influence. The difference between airflows and springs consists in that the airflows consist of incidental groups of molecules of air (not systems) moving in one direction. Amongst these elements there are executive elements (SFU, air molecules), but there is no control block which could construct a springs-type system out of them, i.e. provide the existence of airflows as stable, separate and independent bodies (systems). These airflows are continually created by fan propellers and as they have no control block of their own they always collapse by themselves. Suppose that we construct some kind of a system which will ensure prevention of the airflows from collapse, let’s say, encase them in rubber cylinders, they then may exist independently of fans. But in this case the system of stabilization of the pencil’s vertical position will shift from the active category to the passive. Hence, both active and passive systems consume energy. However, the passive ones consume the external energy brought in by external influence, while the active ones would use their own internal energy. One may argue that internal energy, say, of myocyte is still the external energy brought in to a cell from the outside, e.g. in the form of glucose. It is true, and moreover, any object contains internal energy which at some stage was external. And we probably may even know the source of this energy, which is the energy of the Big Bang. Some kind of energy was spent once and somewhere for the creation of an atom, and this energy may be extracted therefrom somehow or other. Such brought-in internal energy is present in any object of our World and it is impossible to find any other object in it which would contain exclusively its own internal energy which was not brought in by anything or ever from the outside. Energy exchange occurs every time the systems interact. But passive systems do not spend their internal energy in the process of their performance because they “are not able” of doing it, they only use the energy of the external influence, whereas active systems can spend their internal energy. The passive system is the thorax which performs passive exhalation and many other systems of living organism.
Evolution of systems.
Complex control block. For the most efficient achievement of the goal the
system always should carry out its action in the optimum way and produce the
result of action in the right place and time. The system’s control block solves
both problems: where and when it is necessary to actuate. In order to be able
to operate at the right place it should have a notion of space and the
corresponding sensors delivering information on the situation
in the given space. In turn, the time of delivery of
the result of action with simple systems includes two periods: the time spent
for decision-making (from the moment of onset of external influence till the
moment of SFU activation) and the time spent for the
SFU actuation (from the moment of the beginning of
SFU activation till the moment the result of action is achieved). The time
spent for the decision-making depends on duration of cycles of the system’s
performance which issue was discussed above. The time spent for the
SFU actuation depends on the SFU properties such as,
for example, the speed of biochemical reactions in live cells or the speed of
reduction of sarcomere in muscular cells which to a considerable degree depends
on the speed of power consumption by these SFU and the speed of restoration of
energy potential after these SFU have been actuated. These speeds are basically
the characteristics inherent in SFU, but are also determined by service systems
which serve these SFU. They may also be controlled by control block. Metabolic,
hormonal, prostaglandin and vegetative neural regulation in living organism is
intended just for this purpose, i.e. to change to some extent the speeds of
biochemical reactions in tissue cells and conditions of delivery of energy
resources by means of regulation of (service) respiratory and blood circulation
systems. But the notion of “at the right time” means not only the time of
actuation in response to the external influence. In many cases there is a need
for the actuation to start before external influence is exerted. However, the
system with simple control block starts to perform only after the onset of
external influence. It is a very significant (catastrophic) drawback for living
systems, because if the organism is being influenced upon, it may mean that it
is already being eaten. It would be better if the system started to perform
before the onset of this external influence. If the external situation is
threatening by the onset of dangerous influence, the optimal actions of the
system may protect it from such influence. For this purpose it is necessary to
know the condition of external situation and to be able to see, estimate and
know what actions need to be undertaken in certain cases. In other words, it is
necessary to exercise control in order to forestall real result of action prior
to external influence. In order to perform these actions it should contain
special elements which can do it and which it does not have. Simple control
block can exercise control only on the basis of mismatch
(divergence/discrepancy) of real result of action with the preset one, because
the system with simple control block cannot “know” anything about external
situation until the moment this situation starts to influence upon the system.
The knowledge of external situation is inaccessible to simple control block.
Therefore, simple control block always starts to perform with delay. It may be
sometimes too late to control. If the system (the living organism) does not
know the external situation, it may not be able to make projection as to what
the situation is and catch the victim or forestall encounter with a predator.
Thus, simple control block cannot make decisions on the time and place of
actuation. For this purpose control block needs a special analyzer which can
determine and analyze external situation and depending on various external or
internal conditions elaborate the decision on its actions. This analyzer should
have a notion of time and space in which certain situation is deployed, as well
as corresponding informants (sensors with communication lines between them and
this special analyzer) which provide information on the external situation. The
analyzer-informant has nothing of this kind. When the hunter shoots at a flying
duck, it shoots not directly at the bird, but he shoots with anticipation as he
knows that before the bullet reaches a duck it (the duck) will move forward.
The hunter, being a system intended for shooting a duck, should see the entire
situation at a distance, estimate it correctly, make the projection as to
whether it makes sense to shoot, and he should act, i.e. shoot at a duck, only
on the basis of such analysis. He cannot wait until the duck touches him (until
his “X” is actuated) so that he then can shoot at it. In order to do so he
should first single out a duck as the object he needs from other unnecessary
objects, then measure a distance to a duck, even if it would be “by eye”. He
does it by means of special (visual) analyzer which is neither “X” nor “Y
sensor, but is an additional “C” sensor (additional special remote receptors
with afferent paths). Such receptors can be any receptors which are able of
receiving information at a distance (haemo-, termo-, photoreceptors, etc). The
hunter’s visual analyzer includes photosensitive rods and cone cells in the eye
(photoreceptors), optic nerves and various cerebral structures. He should be
able to distinguish all surrounding subjects, classify them and single out a
duck against the background of these subjects and locate a duck (situational
evaluation). In addition, by means of reciprocal innervation he should position
his body in such a way that the gun is directed precisely to the place in front
of the duck (forestalling/ anticipation) to achieve the goal, i.e. to hit the
duck. He does all this by means of his additional analyzer which is the
analyzer-classifier. Simple control block of systems with NF does not contain
such additional analyzer-classifier. That is why it is called “simple”. It has
only analyzer-informant which feels external influence by means of “X” sensor
only when this influence has already begun; it measures the result of action by
means of NF (“Y” sensor) only when this result is already evident and analyzes
the information received after the result of action is already produced,
because it takes time for the NF to activate. In addition, the
analyzer-informant contains only “database” in which the table of due values of
controllable parameters (data) which need to be compared to the data of
measurements of external influence and results of action “is written down” in
explicit or implicit form. It elaborates decisions on the basis of these
comparisons. Its algorithm of control is based only on the comparison of the
given measurements carried out by “X” and “Y” with the “database”. If the
mismatch is equal to “M” it is necessary to perform, for example, less action,
whereas if it is equal to “N”, then more action should be done. Simple control
block cannot change the decision as to the alteration of the level of
controllable parameter, time of actuation and the NF intensity, since it does
not have appropriate information. To perform these actions it should contain
special elements which can provide it with such information. What does it need
for this purpose? In order to make a decision the given block should “know” the
situation around the system which can cause certain external influence. For
this purpose it should first of all “see
it, i.e. have sensors which can receive information
at a distance and without direct contact (remote “C” informant). In addition,
it should contain a special analyzer-classifier which can classify external
environment and single out from it not all the objects and situations, but
those only which may affect the implementation of its goals. Besides, it should
have notions of space and time. The play of fish and even dolphin shoals in the
vicinity of floating combatant ship
cannot affect
its movement to target destination. But the “game
of the enemy submarine in its vicinity may substantially affect the fulfillment
of its task. The combatant ship should be able to “see” all its surroundings
and, based on the external situation, single out from all possible situations
only those that may create such external influences which can prevent it from
the implementation of its objective. For this purpose it should “know” possible
situational scenarios which may affect the achievement of the goal of the given
system. To this effect it should have “knowledge base” containing the
description of all those situations which can affect the implementation of the
objective. If its “knowledge base” does not have the description of certain
objects or situations it cannot distinguish (classify) an object or a situation
and can not make correct decision. The “knowledge base” should store
information not on the parameters of external influence which are stored in the
database”, but on the situations around (beyond) the system which may lead to
specific external influence. The “knowledge base” may be introduced in the
control block at the moment of its “birth” or later together with the command,
at that it is being introduced in the given block by the systems external in
relation to the given system. If its “knowledge base” does not contain the
description of the given situation, it can not distinguish and classify it. The
knowledge base” contains the description of various situations and the
significance of these situations for the system. Knowing the importance of real
situation for the achievement of the goal the system can make projection and
take decision on its actions depending on the projection made. In addition to
the “knowledge base” it should have “decision base”– a set of ready/stored/
decisions that are made by the control block depending on
the situation and the projection, (authorized decisions,
instructions) in which appropriate decisions are stored that need to be made in
respective situations. If it does not have ready decisions regarding external
situation it cannot perform its objective. Having identified a situation and
elaborated the decision, it gives a command to the analyzer-informant which
activates a stimulator in an appropriate way. Thus, the control block is being
complexificated on account of inclusion in its structure of the “C” informant
and the analyzer-classifier containing the “knowledge base
and the “base of decisions”. That is why such
control blocks are called “complex”. The more complex the decision-making block
is, the more precise decision may be chosen. Consequently, complex control
block includes both the analyzer-informant which has “database
and the analyzer-classifier which has the “knowledge base” and the “decision
base”. Not any living cell has analyzer - classifier. Animate/organic/ nature
is classified under two major groups: flora and fauna. Plants, as well as many
other living forms of animate nature, such as corals and bacteria, do not
possess remote sensors, although in some cases it may seem that plants,
nevertheless, do have such sensors. For example, sunflowers turn their heads
towards the sun as if phototaxis is inherent in them. But they actually turn
their heads not towards the light, but towards the side wherefrom their bodies
get more heated, and heat comes from the side wherefrom the light comes. Heat
is felt locally by a sunflower’s body. It does not have special infra-red
sensors. Photosynthesis process is not a process of phototaxis. Hence, plants
are systems with simple control block. In spite of the fact that there are
plants with a very complex structure that are even capable to feed on subjects
of fauna, their control block is still simple and reacts only to direct
contact. For example, a sundew feeds on insects; it can entice them, paste them
to its external stomach and even contract its valves. It’s a predator and in
this sense it is akin to a wolf, a shark or a jellyfish. It can do variety of
actions like an animal, but it can only do it after the insect alights on it. A
sundew cannot chase its victims because it does not see them (remote sensors
are not available). Whatever alights on it, even a small stone, it will do all
necessary actions and try to digest it because it does not have
analyzer-classifier. This is why a sundew is a plant, but not an animal.
Animate cells, including unicellular forms, even such as amoeba or infusoria
types, are systems with complex
control blocks since they possess at least one of spatial analyzers
chemotaxis. It is the presence of remote sensors that differs a cell of an
animal from any objects of flora, in which such sensors controls are not
present. Therefore the control block is a determinant of what kind of nature
the given living object belongs to. The jellyfish is not an alga, but an animal
because it has chemotaxis. Remote analyzer gives an idea about the space in
which it has to move. That is why plants stay put, while animals move in space.
Simple control block including only the analyzer-informant is a determinant of
the world of minerals and plants. We will see below where the difference
between the mineral and vegetative worlds/natures lies. Complex control block
including the analyzer-classifier is a fauna determinant anyway. An amoeba is
the same kind of hunter as a wolf, a shark or a man. It feeds on infusorians.
To catch an infusorian it should know where the latter is and should be able to
move. It cannot see the victim at a distance, but it can feel it by its
chemical sense organs and seek to catch it as it has chemotaxis, possibly the
first of the remote sensor mechanisms. But in addition to chemotaxis the amoeba
should also have a notion (even primitive) of space in which it exists and in
which it should move in a coordinated and task-oriented manner
to catch an infusorian. In addition, it should be
able to single out an infusorian from other objects which it can encounter on
its way. Its analyzer-classifier is much simpler than, for example, that of a
wolf or a shark because it does not have organs of sight and hearing and neural
structures at all, but it can classify external situation. It has complex
control block comprising the “C” informant, and that is why an amoeba is not a
plant, but an animal. Since control blocks may be of any degree of complexity,
reflexes may be of any degree of complexity, too, from elementary axon reflexes
to the reflexes including the cerebral cortex performance (instincts and
conditioned reflexes). The number of reflexes of living organism is enormous
and there exist specific reflexes for each system of the organism. Moreover,
the organism is not only a complex system in itself, but due to its complexity
it has a possibility to build additional, temporary/transient/ systems
necessary at the given point of time for some specific concrete occasion. For
example, lamentation system is a temporary system which the organism builds for
a short time interval. The lamentation system’s control block is the example of
complex control block. The purpose of lamentation is to show one’s suffering
and be pitied. This system includes, in the capacity of composite executive
elements, other systems (subsystems) that are located sufficiently far from
each other both in space and in terms of functions (lacrimal glands,
respiratory muscles, alveoli and pulmonary bronchial tubes, vocal chords, mimic
muscles, etc.). At first the external situation is identified and in case of
need lamentation reflex (complex reflex, an instinct) is actuated under the
certain program, which includes control of lifting up one’s voice up to a
certain timbre (control over the respiratory muscles and vocal chords), sobbing
(a series of intermittent sighs), lacrimation /excretion of tears/, specific
facial expression, etc. All these remote elements are consolidated by the
complex control block in a uniform system, i.e. lamentation system, with very
concrete and specific purpose to show one’s sufferings to the other system. The
lamentation reflex can be realized at all levels of nervous system, starting
from the higher central cerebral structures, including vegetative neural
system, subcortex and up to cerebral cortex. But we are examining only child’s
weeping which is realized in neural structures not higher than subcortex level
(instinctive crying). After the purpose has been achieved (sufferings have been
explicitly demonstrated, and whether or not the child was pitied will be found
out later) the reflex is brought to a stop, this complex control block
disappears and the system disintegrates into the components which now continue
functioning as part of other systems of organism. Lamentation system disappears
(it is scattered). Whence the control block (at subcortex level) knows that it
is necessary to cry now, but it is not necessary to cry at any other moment?
For this purpose it identifies a situation (singles it out and classifies). The
analyzer-classifier is engaged in it. Its “knowledge base” is laid down in subcortex
from birth (the instincts). Simple control block cannot perform such actions.
All actions of the systems controlled by elementary and simple control blocks
would be automatic. Biological analogues of elementary control block are the
axon reflexes working under the “all-or-none” law; those of simple control
blocks are unconditional (innate, instinctive) reflexes when certain automatic,
but graduated reaction occurs in response to certain external influence. Simple
control block would be adapting the system’s actions better than the elementary
one because it takes account of not only external influence, but the result of
action of the system which has occurred in response to this external influence
as well. But it cannot identify a situation. Complex control block can perform
such actions. It reacts not to external influence, but to certain external
situation which can exert certain external influence. Biological analogues of
complex control block are complex reflexes or instincts. During pre-natal development
the “knowledge” of possible situations “is laid down” into the brain of a fetus
(the “knowledge base”). The volume of this knowledge is immense. A chicken can
run immediately after it hardly hatches from egg. A crocodile, a shark or a
snake become predators right after birth, i.e. they know and are able of doing
everything that is required for this purpose. It speaks of the fact that they
have sufficient inborn “knowledge base” and “base of decisions” for this
purpose. In such cases we say that animal has instincts. Thus, the system with
complex control block is the object which can react to certain external
situation in which this influence may be exerted. But it can react only to
fixed (finite) number of external situations
which description is contained in its “knowledge
base” and it has a finite number of decisions on these situations which
description is contained in its “base of decisions”. In order to identify
external situation it has the “C” informant and the analyzer-classifier. In
other respects it is similar to the system with simple control block. It can
also react to certain external influence and its reaction is stipulated by type
and number of its SFU. The result of action of the system is also graduated.
The number of gradations is defined by the number of executive SFU in the
system. It also has the analyzer-informant
with the “database”, DPC (the “X” informant) and NF
(the “Y” informant), which control the system through the stimulator (efferent
paths). There are no analogues with complex control block in inorganic
/abiocoen, inanimate/ nature. Biological analogues of systems with complex
control block are all animals, from separate cells to animals with highly
developed nervous system including cerebrum and remote sense organs, such as
sight, hearing, sense of smell, but in which it is impossible to develop
reflexes to new situations, for example, in insects. The analogues of the “C
informant are all “remote” receptors: eyesight (or its photosensitive
analogues in inferior animals), hearing and sense of
smell. The analogues of analyzer-classifier are, for example, visual,
acoustical, gustatory and olfactory analyzers located in the subcortex. Visual,
acoustical, gustatory and olfactory analyzers located in the cerebral cortex
are anyway referred to analyzers-correlators.
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