KR20100036516A - Syetem and method for calculating stress level, storage medium storing the same - Google Patents

Abstract

PURPOSE: A system and a method for calculating stress, and a storage medium thereof are provided to calculate a stress index accurately by reflecting not only environmental and physical factors but also psychological and usual stress. CONSTITUTION: An environment sensing unit(10) measures an environmental stress factor. The environmental stress factor comprises a temperature, humidity, a noise and carbon dioxide concentration. A body sensing unit(20) measures a biological stress factor. A calculator(30) calculates original stress index by receiving the measurement figure of the environment and body sensing units. A controller(40) produces an control stress index by reflecting the unusual stress and usual stress to the original stress index.

Description

System and method for calculating stress index and storage medium thereof

The present invention relates to a stress index calculation system and method and a storage medium thereof. More specifically, the original stress level is calculated by using environmental and body sensing information, and the adjusted stress level is reflected by reflecting the daily stress caused by the daily events and the daily stress using the indirect data. By calculating, the stress index can be calculated more accurately by reflecting not only environmental and physical factors but also psychological and daily stresses. The present invention relates to a stress index calculation system and method and a storage medium capable of automatically calculating a stress index by interlocking with each other.

In modern life, stress not only causes various diseases but also has a great influence on the quality of life. Therefore, the problem of how to manage such stress is a very important topic for modern people.

Stress appears in different ways, depending on the physical and mental characteristics of the individual, and is also affected by the circumstances of the individual. Therefore, accurately measuring the stress index of different individuals is a prerequisite for individual stress management.

Most of the methods for measuring stress are non-technical methods in the form of questionnaire or self-answer by a medical professional. For example, if a questionnaire is given that gives a score according to the stress level to people in various events occurring in daily life, the respondents may rank the stress level in several grades according to the total score determined according to the type and number of events that apply to them. Make it understandable. For example, if the total score is less than 200 points, it is judged that you have lived a safe and calm life, and if you are between 200 and 300 points, you have been stimulated to energize your daily life. You can judge that you are suffering from stress. In the questionnaire-type stress calculation methods, items that fit the detailed context, such as job stress and parenting stress, were developed separately. Measuring stress by this method is not only time consuming, but also has a lot of room for subjective judgment of the respondents, making it difficult to make accurate measurements, unlike humans who can directly induce stress or determine the degree of stress. There is a problem that the stress that is automatically perceived in the insensitive state is not reflected in this routinely exposed specific situation.

Recently, efforts have been made to automate stress measurements unlike these non-technical methods. In fact, devices such as stress eraser and stress doctor that measure the degree of stress by measuring bio signals such as body heat and HRV (Heart Rate Variability) are commercially available at home and abroad. However, these methods also have a problem that they do not effectively use the advanced technology for measuring stress. In addition, the accuracy of the measurement is reduced by judging the degree of stress using only a few limited number of biosignal changes, and like the questionnaire form, the stress that is automatically recognized in the insensitive state is not reflected, and the measured result is reduced in stress. There is a problem that can not be linked directly to the service for the service.

The present invention has been devised to solve the above problems, and in particular, it is possible to calculate the stress index more accurately by reflecting not only environmental and physical factors but also psychological and daily stress, and calculate the stress index more quickly and automatically. The purpose of the present invention is to provide a stress index calculation system and method and a storage medium thereof.

Stress index calculation system according to the present invention devised to achieve the above object is an environmental sensing unit for measuring the environmental stress factor; A body sensing unit measuring a biological stress factor; A calculation unit configured to receive the measured values of the environmental sensing unit and the body sensing unit to calculate an original stress level; And an adjusting unit for calculating an adjusted stress level by reflecting the abnormal stress caused by life events and the daily stress using indirect data including traffic jams in the raw stress index.

In addition, the environmental stress factors may include temperature, humidity, noise, carbon dioxide (CO ₂ ) concentration.

In addition, the bio-stress factor may include pulse, iris, blood pressure, brain waves, body temperature.

The calculation unit may further include: a factor grade determining unit configured to determine whether the measured value of the environmental sensing unit and the measured value of the body sensing unit correspond to a stress level; A stress score calculator configured to calculate a stress score by using the number of factors corresponding to each grade and a weight for each grade as a result of the determination of the factor grade determiner; And a stress grade determination unit for determining a stress grade corresponding to the stress score calculated through the stress score calculator.

In addition, the stress score calculator may calculate a stress score by the following equation.

Stress score = α ₁ β ₁ + α ₂ β ₂ + ... + α _i β _i

In addition, the extraordinary stress can be measured by the stress measurement item of Holmes and Rahe.

In addition, the adjustment unit may adjust the raw stress index up one level only when the total score of the abnormal stress is equal to or greater than the critical score.

In addition, the daily stress can be measured by calculating the exposure time by vehicle position recognition.

In addition, location recognition of the vehicle may be performed by GPS.

In addition, the daily stress may be measured to further reflect the elapsed time.

In addition, the adjusting unit may adjust the raw stress index up one level only when the level of the daily stress is equal to or higher than a critical level.

Stress index calculation method according to the present invention comprises the steps of (a) calculating the raw stress index using body and environmental sensing information; (b) adjusting the grade of the raw stress index by measuring the extraordinary stress caused by the life event; And (c) adjusting the grade of the raw stress index by measuring the daily stress caused by the indirect data including the traffic jam.

In addition, the step (a) may comprise the steps of (a1) determining the degree of stress each measured value of the body and environmental sensing information; (a2) calculating a stress score using the number of factors corresponding to each grade and the weight of each grade as a result of the determination of step (a1); And (a3) may comprise the step of determining the stress level corresponding to the stress score calculated through the step (a2).

In addition, in step (a2), the stress score may be calculated by the following equation.

Stress score = α ₁ β ₁ + α ₂ β ₂ + ... + α _i β _i

In addition, the extraordinary stress of step (b) can be measured by the stress measurement item of Holmes and Rahe.

In addition, in step (b), the raw stress index may be increased by one level only when the total score of the extraordinary stress is greater than or equal to a critical score.

In addition, the daily stress of step (c) can be measured by calculating the exposure time by the location recognition of the vehicle.

In addition, the daily stress of step (c) can be measured by further reflecting the elapsed time.

In addition, in step (c), the raw stress index may be increased by one level only when the level of the daily stress is above a critical level.

According to the present invention, the original stress level is calculated by using the environment and body sensing information, and the adjusted stress level is adjusted by reflecting the daily stress caused by the living event and the daily stress using the indirect data. By calculating, the stress index is more accurately calculated by reflecting not only environmental and physical factors but also psychological and daily stress.

In addition, according to the present invention, by using the context-aware ubiquitous computing technology, the environment / body sensor, the administrative information system, and the GPS are linked to each other, so that the stress index can be automatically calculated more quickly.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible, even if shown on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the following will describe a preferred embodiment of the present invention, but the technical idea of the present invention is not limited thereto and may be variously modified and modified by those skilled in the art.

1 is a configuration diagram of a stress index calculation system according to a preferred embodiment of the present invention, Figure 2 is a detailed configuration diagram of the calculation unit in FIG.

The stress index calculation system according to a preferred embodiment of the present invention, referring to FIG. 1, includes an environmental sensing unit 10, a body sensing unit 20, a calculation unit 30, and an adjustment unit 40. Hereinafter, for convenience, the stress index calculated by the calculation unit 30 using the measured values of the environmental sensing unit 10 and the body sensing unit 20 is referred to as an "original stress level", and the adjusting unit 40 The stress index reflecting the stress caused by living events and indirect data will be referred to as "Adjusted Stress Level".

Environmental sensing unit 10 is a part for measuring the stress factor caused by the environment in order to reflect the stress of the environment surrounding the human in the stress index calculation. Environmental stress factors include temperature, humidity, noise, carbon dioxide (CO ₂ ) concentration, and the like. The environmental sensing unit 10 measures a value of a stress factor by installing a temperature sensor and a humidity sensor at a location where a person who wants to calculate a stress index spends a lot of time, and measures it using a ubiquitous sensor network (USN) technology. The numerical value is transmitted to the calculation unit 30.

The body sensing unit 20 is a part for measuring a stress factor by the living body in order to reflect the stress that the human body responds to in calculating the stress index. Stress factors caused by living organisms include pulse (heart rate), iris, blood pressure, brain waves, and body temperature. The body sensing unit 20 attaches a body sensor to a body of a person who wants to calculate stress to measure a value of a stress factor, and similarly transmits the measured value to the calculation unit 30 using ubiquitous sensor network technology. .

The calculator 30 is a part that receives the measured values of the environmental sensor 10 and the body sensor 20 to calculate the original stress index. In order to determine the raw stress index, it is necessary to know how much stress each physical and environmental stressors are causing. To this end, the calculation unit 30, with reference to Figure 2, may be provided with a factor rating determination unit 32, a stress score calculation unit 34, a stress rating determination unit 36.

The factor grade determining unit 32 is a part for determining how many levels of environmental and physical stress measurement factors correspond to the stress level. In Table 1, the numerical change of environmental stressors was classified by stress level ranging from 0 to 3. In addition, in Table 2, the numerical changes of physical stress measurement factors were divided by stress grades ranging from 0 to 3. Through this, it is possible to determine the current level of stress due to the factors according to the current level of each factor.

Dimension Stress items level        Environment  Temperature Grade 0 Comfortable (18 ~ 20 ℃) Grade 1 Normal (15 ~ 18 ℃, 20 ~ 23 ℃) Grade 2 Hot (23 ~ 29 ℃) Grade 3 Unpleasant (15 ℃ or below, 29 ℃ or above)  Humidity Grade 0 Comfort (40 ~ 60%) Grade 1 Slightly humid (60-80%) Grade 2 Somewhat dry (30-40%) Grade 3 Unpleasant (30% or less, 80% or more)  noise Grade 0 Comfortable (less than 30dB) Grade 1 Medium (30 ~ 50dB) Grade 2 Disturbance (50 ~ 60dB) Grade 3 Hygienic Limits (above 60dB)  carbon dioxide Grade 0 Comfortable (500 ~ 1000ppm) Grade 1 Rather high (1000-2000ppm) Grade 2 High (2000 ~ 3000ppm) Grade 3 Hazard (3000 ~ 4000ppm)

Dimension Stress items level          Biological  Pulse (heart rate) Grade 0 Stable (70 ~ 80 times / minute) Grade 1 Low (60 ~ 70 times / min) Grade 2 High (80 ~ 90 times / minute) Grade 3 Risk (less than 60 times, more than 90 times)  Iris Grade 0 Sunny Grade 1 Somewhat congestion Grade 2 congestion Grade 3 Very hyperemia  Blood pressure Grade 0 Titration (80/120) Grade 1 Hypertension (80 ~ 89/121 ~ 139) Grade 2 Hypertension Level 1 (90 ~ 99/140 ~ 159) Grade 3 Hypertension Level 2 (over 100 / over 160)  EEG Grade 0 Stable (Theta Wave, 4-8 MHz) Grade 1 Relaxation (alpha, 8-14 MHz) Grade 2 Tension (beta wave, 14 ~ 30MHz) Grade 3 Excitation (gamma wave, 30-50 MHz)  temperature Grade 0 Normal (36.5 ℃) Grade 1 Low heat (37 ℃) Grade 2 High temperature (38 ℃) Grade 3 Danger (39 ℃)

Blood pressure values in Table 2 means (dilator blood pressure / systolic blood pressure).

The stress score calculator 34 calculates the stress score by obtaining information on how many stresses each of the nine factors corresponds to through the factor grade determiner 32, and comprehensively determining them. The stress score is calculated by checking how many factors (β) are included in each grade and reflecting the weight of each grade (α). In one example, the stress score may be calculated by the following equation.

Stress score = α ₁ β ₁ + α ₂ β ₂ + ... + α _i β _i

Here, α _i represents a weight of the i grade, and may be set as, for example, the weight α ₁ = 1 for the first grade, the weight α ₂ = 2 for the second grade, and the weight α ₃ = 3 for the third grade. In addition, β _i represents the number of factors corresponding to class i. Weights are considered to weight higher classes when the number of factors in each class is the same. For example, if the number of factors in class 2 and the number of factors in class 3 are the same, the number of factors in class 2 is multiplied by 2 and the number of factors in class 3 is multiplied by 3 to differentiate them by class. To be made.

The stress rating determiner 36 determines the stress rating using the calculated stress score. The method of determining the stress level by using the stress score can be obtained when all the 1 to 9 factors are all 3 levels, which are ranged as the minimum and maximum values that can be obtained when all 9 factors are 0 level. You can find the location of the stress score in the stress rating table (Table 3), which is divided into three levels, which are ranged by the minimum and maximum values. This method has the advantage that it can be applied equally even if the number of stress measuring factors changes.

Level Score 0 0 One 1-9 2 10-18 3 19-27

When the results measured by the environmental sensing unit 10 and the body sensing unit 20 are as shown in Table 4 below, the stress rating is calculated as follows.

Stress items level Temperature 19 ℃ Humidity 32% noise 29 dB carbon dioxide 600 ppm pulse 62 times temperature 37 ℃ Blood pressure 140 Iris Very hyperemia EEG Thetapa

The factor grade determining unit 32 receives data as shown in Table 4 from the environment sensing unit 10 and the body sensing unit 20, and the stress caused by the factor depends on the current value of each factor. Find out what your rating is. As a result, the factor grade determining unit 32 determines the grade of each stress factor as shown in Table 5 on the basis of Table 1 and Table 2.

Stress items Rating Temperature 0 Humidity 2 noise 0 carbon dioxide 0 pulse One temperature One Blood pressure 2 Iris 3 EEG 0

The stress score calculator 34 counts the number of factors corresponding to each grade, and calculates a stress score by multiplying the number of each factor by a weight. There are four classes 0, two classes 1, two classes 2, and one class 3, so β ₀ = 4, β ₁ = 2, β ₂ = 2, and β ₃ = 1.

If α ₁ = 1, α ₂ = 2, α ₃ = 3, the stress score is calculated as

Stress score = 1 × 2 + 2 × 2 + 3 × 1 = 9

The stress rating determination unit 36 substitutes nine points, which are calculated stress scores, into Table 3 to determine the stress rating as the first grade.

Since the raw stress index calculated by the calculation unit 30 reflects only the stress caused by physical and environmental factors, the psychological stress caused by the abnormal events and the specific stress that are exposed to everyday life are reflected. Not. The adjusting unit 40 calculates the adjusting stress index by adjusting the stress level by reflecting the daily stress and the daily stress caused by the living event in the raw stress index calculated by the calculating unit 30.

① Consideration of unusual stress

Significant life events that humans experience cause significant psychological stress. Holmes and Rahe's stress measures, for example, translate the extraordinary stress caused by these life events into scores. For example, a spouse's death is 100 points and a family's illness is 44 points.

The occurrence of such life events can be identified through the administrative information system. In particular, since data on online complaints of individuals have been collected due to the recent expansion of electronic complaints, the coordinator 40 can effectively extract and receive the occurrence of life events by effectively using such data. For example, if a home server in a firewall is storing such data in a cache, Holmes and Rahe's stress measures can be calculated automatically instead of the questionnaire method.

In the case of Holmes and Rahe, which divides stress information into three stages based on the total score that can be obtained according to the occurrence of life events, the third stage represents a dangerous situation that causes disease. Since it is considered to be a positive stimulus, it can be judged that only the third stage has the meaning of adjusting the raw stress index. If the total score is 200 points or less, if the first stage, 200 ~ 300 points 2 stages, 300 points or more if divided into three stages adjuster 40 adjusts the original stress index only when the total score is 300 points or more. For example, when the total score is 300 points or more, the adjustment unit 40 may adjust the raw stress index calculated by the calculation unit 30 up one grade. In the above example, since the raw stress index is a first grade, an increase of one grade raises the second grade.

② Consider everyday stress

The daily stress information collected through indirect data differs from physical and environmental measures that directly induce stress or to determine the degree of stress. Holmes and Rahe contain important events that occur abnormally in human life. It is also different from the measurement item of. Routine stress refers to stress that automatically recognizes certain stress situations that human beings are exposed to everyday.

Traffic jams, for example, are a common situation for urban dwellers and have a great impact on stress. Environmental and physical sensing and extraordinary stress alone cannot account for such significant situations as traffic jams, which are critical to the stress of urban dwellers. It is desirable to be able to determine the stress level more accurately by recognizing such a situation because the stress caused by traffic jams in the situation of frequent congestion or busy schedule among the commuting route of workers is very strong. If the situation is automatically recognized through the ubiquitous computing environment and the stress level is calculated according to the degree and reflected in the final stress level of the individual, it can be the most appropriate stress calculation method for the ubiquitous computing environment. Of course, indirect data on everyday situations other than traffic jams can also be taken into account in stress coordination.

3A and 3B are conceptual views illustrating a stress calculation method using indirect data.

A representative way to determine how much traffic a person is exposed to is a vehicle's location awareness. Vehicle location recognition is possible using GPS, a key technology in commercial navigation and telematics services. The "exposure time", which is the time when the individual vehicle passed through the congestion section, can be easily calculated by the GPS checking the congestion section entry time and the congestion section entrance time. The longer the exposure time is compared to the average travel time, the more likely the vehicle occupant is to be stressed.

In addition, the degree of stress may vary depending on the time required from the time when the exposure to the traffic jam situation is completed, that is, the "elapsed time". The longer this elapsed time can be expected to decrease the degree of stress. Table 6 below is an example of setting the stress level according to the exposure time and the elapsed time.

Rating Exposure time Elapsed time Grade 3 ≥2 ≤1 Grade 2 ≥1 ≤2 Grade 1 ≥0.5 ≤3 Grade 0 ≥0 ≤4

For example, as shown in FIG. 3B, when the vehicle runs from the Hannam Bridge to the Seoul Tollgate, the average travel time is 30 minutes, whereas if the exposure time of a specific driver is 2 hours and the elapsed time is within 1 hour, the daily stress level is 3 Becomes In order to measure the stress index by using indirect data due to traffic jam, factors such as the presence or absence of important schedules can be considered in addition to the exposure time and the elapsed time.

In this case, in the case of the third grade, which is the most severe grade, the adjusting unit 40 adjusts the raw stress index calculated in the previous step by one grade. If the exposure time is 2 hours and the elapsed time is less than 1 hour, in the above example, the final stress level is calculated as a third level by adjusting the second level adjusted by the daily stress up by one level.

In this way, the final stress level is calculated, and the final stress level may reflect not only environmental and physical stressors, but also daily stresses such as psychological stress and traffic jams caused by extraordinary life events.

4 is a flowchart illustrating a stress index calculation method according to a preferred embodiment of the present invention. Stress index calculation method according to a preferred embodiment of the present invention, for example, may be implemented by the stress index measuring apparatus according to a preferred embodiment of the present invention, but is not limited thereto.

Step S10 is a step of calculating the stress level using the body and environment sensing information. This calculates the raw stress index.

Although not shown, step S10 provides information on how many stresses each factor corresponds to through a factor class determining step and a factor class determining step to determine how many stress levels each environmental and physical stress measurement factor corresponds to. It may include a stress score calculation step of calculating the stress score by determining the comprehensively obtained, and a stress rating determination step of determining the stress rating using the calculated stress score.

Step S20 is a step of measuring the stress caused by the life event and using it to adjust the stress level. For this purpose, the criteria of Holmes and Rahe can be used, and if the total score is above a certain value, the raw stress index calculated through step S10 can be adjusted up by one class.

Step S30 is a step of measuring the stress caused by the indirect data and adjusting the stress level using the same. The stress index is measured using indirect data due to traffic jams, and as a result, if the level is higher than or equal to a certain grade, the raw stress index calculated through step S10 may be increased by one grade.

Through this process, the adjusted stress index, that is, the final stress level is calculated (S40).

Meanwhile, the present invention can be embodied as computer readable codes on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored.

Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disks, optical data storage devices, and the like, which may be implemented in the form of a carrier wave (for example, transmission over the Internet). Include. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. In addition, functional programs, codes, and code segments for implementing the present invention can be easily inferred by programmers in the art to which the present invention belongs.

The above description is merely illustrative of the technical idea of the present invention, and various modifications, changes, and substitutions may be made by those skilled in the art without departing from the essential characteristics of the present invention. will be. Accordingly, the embodiments disclosed in the present invention and the accompanying drawings are not intended to limit the technical spirit of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by the embodiments and the accompanying drawings. . The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

The present invention can function as an advanced service field of telematics / navigation, and can be widely used in the field of u-SMC (Stress Management Center) for providing an optimal antistress service.

1 is a block diagram of a stress index calculation system according to a preferred embodiment of the present invention,

2 is a detailed configuration diagram of the calculation unit in FIG. 1;

3A and 3B are conceptual views illustrating a stress calculation method using indirect data;

4 is a flowchart illustrating a stress index calculation method according to a preferred embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

10-environmental sensing unit 20-body sensing unit

30-calculation unit 32-factor class determination unit

34-stress score calculator 36-stress rating calculator

40-adjuster

Claims (20)

An environmental sensing unit measuring an environmental stress factor; A body sensing unit measuring a biological stress factor; A calculation unit configured to receive the measured values of the environmental sensing unit and the body sensing unit to calculate an original stress level; And Adjusting unit for calculating the adjusted stress level by reflecting the daily stress by the daily events and the daily stress using indirect data including traffic jams in the raw stress index Stress index calculation system comprising a. The method of claim 1, The environmental stress factor is a stress index calculation system comprising temperature, humidity, noise, carbon dioxide (CO ₂ ) concentration. The method of claim 1, The biological stress factor is a stress index calculation system, characterized in that it comprises a pulse, iris, blood pressure, brain waves, body temperature. The method of claim 1, wherein the calculation unit A factor grade determining unit for determining whether the measured values of the environmental sensing unit and the measured values of the body sensing unit correspond to the stress levels; A stress score calculator configured to calculate a stress score by using the number of factors corresponding to each grade and a weight for each grade as a result of the determination of the factor grade determiner; And Stress grade determination unit for determining the stress level corresponding to the stress score calculated by the stress score calculation unit Stress index calculation system comprising a. The method of claim 4, wherein The stress score calculator is a stress index calculation system, characterized in that for calculating the stress score by the following equation. Stress score = α ₁ β ₁ + α ₂ β ₂ + ... + α _i β _i The method of claim 1, The extraordinary stress is a stress index calculation system, characterized in that measured by the stress measurement items of Holmes and Rahe. The method of claim 6, And the controller adjusts the original stress index by one level only when the total score of the extraordinary stress is equal to or greater than a critical score. The method of claim 1, The daily stress is a stress index calculation system, characterized in that measured by calculating the exposure time by the location recognition of the vehicle. The method of claim 8, The position index of the vehicle is a stress index calculation system, characterized in that performed by GPS. The method of claim 8, The daily stress is stress index calculation system, characterized in that further measured by reflecting the elapsed time. The method of claim 10, And the controller adjusts the raw stress index by one level only when the level of the daily stress is equal to or greater than a critical level. (a) calculating a raw stress index using physical and environmental sensing information; (b) adjusting the grade of the raw stress index by measuring the extraordinary stress caused by the life event; And (c) calibrating the raw stress index by measuring everyday stress from indirect data including traffic jams; Stress index calculation method comprising a. The method of claim 12, wherein step (a) (a1) determining how many stress levels the measured values of the physical and environmental sensing information correspond to; (a2) calculating a stress score using the number of factors corresponding to each grade and the weight of each grade as a result of the determination of step (a1); And (a3) determining the stress level corresponding to the stress score calculated through step (a2) Stress index calculation method comprising a. The method of claim 13, In the step (a2), the stress index calculation method characterized in that the stress score is calculated by the following equation. Stress score = α ₁ β ₁ + α ₂ β ₂ + ... + α _i β _i The method of claim 12, The method for calculating the stress index, characterized in that the (b) the everyday stress is measured by the stress measurement items of Holmes and Rahe. The method of claim 15, In the step (b), the stress index calculation method characterized in that the raw stress index is increased by one level only when the total score of the extraordinary stress is above the critical score. The method of claim 12, The daily stress of step (c) is calculated by calculating the exposure time by the vehicle's location recognition stress index calculation method. The method of claim 17, The daily stress of the step (c) is a stress index calculation method, characterized in that measured by further reflecting the elapsed time. The method of claim 18, In the step (c), the stress index calculation method, characterized in that the raw stress index is increased by one grade only when the grade of the daily stress is above the critical grade. 20. A computer readable storage medium having a program containing the stress index calculation method according to any one of claims 12 to 19.

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