Keywords

1 Introduction

In Japanese culture there are many items in which name includes Chinese character of Dou, Do or Michi (道). For example; international sport of Jyudo, Japanese fence of Kendo, Japanese archery of Kyuudo, next new olympic game event of Karatedo, Japanese flower arrangement of Kado, enjoying smell of Koudo, Charigrapy of Syodo, and enjoying powder tea of Sado are good item. Dou is Japanese people’s sense of values and the meaning of Dou is training of person’s mentality through activity in one item.

Among them Sado was established by Rikyu Sen during Azuchi-Momoyama period (1573–1603). The main concept is OMOTENASHI mind which is Japanese hospitality. In Sado each action involves the meaning and it can be said that all of action is supported by OMOTENASHI mind. A once-in-a-lifetime chance concept which we cherish our encounter is good example.

Recently Sado has been of particular interest among business persons for training mentality. In tea ceremony room person’s mental becomes steady and such environments create new findings of business. However, there very few researches which discuss about people’s physiological response in tea ceremony room. In this paper participant heart periods were measured. The participants were selected as 5 categories; Japanese persons who knows Sado well, Japanese person who did not know Sado, Japanese students, foreign students who attended tea ceremony explanation lecture or not. Value of tone and entropy was calculated and generation of peaceful mind c in the tea room was discussed.

2 Tea Ceremony

Tea ceremony supported by Urasennke can be divided into 7 processes. Those are 1, Enter the room and sit down 2, Sweets are served 3, Tea-serving manners begin 4, Eat sweets 5, Tea is served 6, Drink tea 7, Head towards the end.

As shown in Fig. 1.

Fig. 1.
figure 1

Process of tea ceremony.

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3 Experimental Procedure

Tea ceremony room is shown in Fig. 2 The area is 7.3 m2 which is composed by 4.5 sheet of Tatami. One Tatami is 90 cm × 180 cm. Shape is square. On Friday, November 4th, Inside Umekoji Park Green mansions.

Fig. 2.
figure 2

Tea ceremony room

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Experiment plan

Experiment subject waiting room Laboratory A. Heart rate experiment Laboratory B.

Subject group 8 mats

  • 10:00 Start of experiment 10:00 ③Japanese students

  • 11:10 ①Kyoto’s peoples 12:20 Break time

  • 13:10 ④Tea ceremony explanation lectured foreign students

  • 14:20 ⑤Tea ceremony explanation not lectured foreign students

  • 15:30 ②Osaka’s peoples

  • 16:40 The experiment end

Autonomic nervous activity is evaluated by measuring the heart beat interval (RRI) with your feeling of tension and relaxation when tea-serving manners.

  1. 1.

    Subject wearing heart rate meter in separate room. After wearing, confirm that the sensor and the monitor are connected.

  2. 2.

    Everyone presses the video camera’s shooting start and heart rate meter switch at the same time. Then rest for about 10 min. Camera charge hold the video camera with your hand and shoot.

  3. 3.

    After that, move to tea room. In the meantime, video camera keeps shooting. Heart rate meter remains measured.

  4. 4.

    Set the camera in the tea room. And, everyone starts about position.

  5. 5.

    After finishing, the shooting of the video camera is ended. The heart rate meter is also ended.

4 Result and Discussion

4.1 Behavior of Participants in Tea Ceremony Room and Process Analysis

According previous analysis tea ceremony can be divided into 7 process. Table 1 shows participants behavior in tea ceremony room.

Table 1 Table 1.
Full size table

This is useful data for investigate serenity by using RR interval of heart rate meter. Therefore, precious observation was needed. In this table process 1 is from 0:00 to 03:20, 2 is from 03:20 to 05:47, 3 is from 05:47 to 06:44, 4 is from 06:44 to 08:03, 5 is from 08:03 to 11:17, 6 is from 11:17 to 11:42 and 7 is from 11:42 to 20:31. Figure 3 shows example photos just before and after drinking tea. Right side white shirt man was focused. Before drinking tea, his face was very nervous, on the other hand after drinking we can found smile on his face. This simple result suggests us that tea ceremony brought some change in feelings.

Fig. 3.
figure 3

Example photos just before and after drinking tea.

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4.2 RR Interval Measurements

Tone-entropy method

The methodology of analysis has been described in detail previously. [1,2,3] In brief, acquired heart periods (R-R intervals) are transformed into percentage index (PI) time series:

$$ {\text{PI}}\left( {\text{n}} \right) = \frac{H\left( n \right) - H(n + 1)}{H(n)} \times 100 $$

where [H(n)] is a heart period time series, and n a serial number of heart beats. The tone is defined as an arithmetic average (first-order moment) of this PI time series as:

$$ \sum\nolimits_{n} {\frac{PI(n)}{N}} $$

where N is a total number of PI terms. The entropy is defined on PI probability distribution by using Shannon’s formula [4]:

$$ - \sum\nolimits_{i} {p(i)\log_{2} p(i)} $$

where p(i) is a probability distribution that PI(n) has value in the range, i ≤ PI(n) < i + 1, i an integer.

In this experiments Data 3 min before and after of drinking tea was selected. Value of tone and entropy was calculated and mean value was obtained.

The tone, balance between acceleration (PI > 0; decrease of heart period) and inhibitions (PI < 0; increase of heart period) of the heart, because positive PI reflects instantaneous accelerations and negative. PI instantaneous inhibition of heart, respectively. At first sight, one might consider that the tone is tobe zero for stable heart rate process. However, the actual tone is not zero, rather reflects the sympathy-vagal balance faithfully as appreciated in all the previous studies [1,2,3]. The entropy evaluates total acceleration-inhibition activities, or total heart period variations, in a familiar unit of bit. As the results of Wilcoxon signed-rank test, tone decreased significantly (p < .05), whereas entropy didn’t change.

Figure 4 shows the entropy and tone charge before and after drinking tea. Both values shows decreasement that means total acceleration-inhibition activities are decreased by the entropy data, and also the tone tends decreasement, which indicate relaxation of feeling. The tone data is significant at 5% level.

Fig. 4.
figure 4

Tone-average and Entropy-average

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5 Conclusion

In this paper the peace of mind of the guest during Japanese tea ceremony can be obtained or not was discussed. The systematic experiments were performed and the number of participants were 25 totally including 5 different groups. First the process analysis was made during tea ceremony and 3 min before and after drinking tea was focused. By using heart rate meter value of tone and entropy was calculated. Consequently, peaceful mind can be generated by drinking tea was clarified.