Understanding the social effects induced by the ambient observation of a robot is essential for their successful integration into human environments. This study explores the influence of eye-related design factors of robots on human perceptions associated with social facilitation. We conducted an online experiment to test the hypothesis that visual and behavioral features of the eyes of a robot influence the feeling of being watched and perceived agency, which together shape public self-awareness. Using a 2 × 3 ×2 ×2 between-subjects design, we manipulated four eye-related factors in a virtual robot: visual realism, size, gaze cue, and blinking. Our analysis revealed that, contrary to our expectations, visual realism and size did not influence the feeling of being watched. However, gaze cue positively affected perceived agency while blinking enhanced it. Perceived agency, in turn, emerged as a significant predictor of public self-awareness. The structural model highlighted a significant relationship: perceived agency enhances the feeling of being watched. These findings suggest that perceived agency mediates the relationship between robotic eye behaviors and public self-awareness. This study provides foundational insights for designing social robots to enhance human experiences in shared spaces.

Differences in text perception among users of diverse language backgrounds may be accentuated in immersive environments. To investigate this, we measured preferred perceptual viewing distances in virtual reality (VR) as a function of language familiarity, glyph complexity, font weight and font type. 30 native readers each of Chinese, English, and Japanese adjusted text panels—initially placed at 0.5 m, 2.5 m, 5 m, and 10 m—to the distance they perceived as most appropriate for reading. Stimuli varied in visual complexity (simple vs. complex characters or words) and in font style (serif vs. sans-serif, light vs. bold). Our results show that at the farthest distances, native English and Japanese readers positioned text significantly farther away than non-natives, indicating a top-down perceptual compensation effect; this advantage was not observed for native Chinese participants. Moreover, at the closest distances, native English readers also required slightly farther viewing distances across all language conditions. Across all groups, simple glyphs and bold fonts supported greater perceptual distances, whereas complex glyphs and light fonts required closer viewing. These findings suggests that how language background and font variables shape text perception in VR and provide a theoretical basis for adaptive rendering to optimize display parameters for diverse user populations.

Online music videos on video-sharing platforms offer video comments that viewers can read to enjoy their social-viewing experience. However, because these comments rely on visual elements through texts, they are not accessible to eyes-free listeners, such as those who listen to music videos while jogging, commuting, or showering. To address this gap, we explore Auditory Comment Display (ACD), which offers text comments via text-to-speech (TTS) synthesis, enabling eyes-free listeners to enjoy a social-viewing experience while listening to music videos. We used music concert videos as example content and prototyped varying comment-to-speech styles in this context. We conducted a formative study (N = 8), prototyping (N = 10), and a user study (N = 12). The results indicated that ACD enhanced eyes-free listeners' social-viewing experience, although it may not be appropriate for specific situations and users. We discuss the design implications and future directions for the eyes-free social-viewing experience via comment-to-speech synthesis.

Eyes have been widely found to play an important role in communicating emotions and intentions for social robots. However, when introducing robots with eyes into people’s personal living spaces, it is necessary to consider how the social aspects of a robot impact perceptions of privacy. Specifically, in this paper we explored how the design of a robot’s eyes and eye-use behavior impacts use perception of privacy and related concerns. We developed a prototype robot with display-based eyes and investigated the impacts on perceptions of privacy concerns living with the robot. Our findings indicated that robot eye design does impact perceptions of privacy concerns, with the unexpected result of robots whose eyes that stay always on garnering lower concerns than eyes that close or turn off (the display) just before a person leaves. This result offer valuable insights for robot development and present empirical evidence on the influence of robot eye design on user privacy concerns.

Perspective-taking, which enables individuals to consider the thoughts and objectives of another, is well established to be a successful strategy for encouraging pro-social behavior in human-computer interactions. Nowadays, perspective-taking is no longer limited to text; it is now more frequently used in virtual reality (VR). However, most previous research has focused on simulating human-human interactions in the real world in VR by providing participants with experiences connected to different moral tasks. In this study, we investigated whether participants’ prosocial behaviors toward robots would change if they experienced an altruistic VR task involving robots from the perspective of different robots. Our findings show that participants who had the help-receiver-view exhibited more altruistic behaviors toward a robot than those who had the help-provider-view one in a dictator game. We believe that this work is the first attempt to investigate the relationship between perspective-taking in a VR environment and changes in prosocial behavior in human-robot interaction.

Behavioral economics has revealed that human decision making is not rational and logical as previously thought. It is strongly dependent on the environment and context, and is influenced by various biases. In this paper, we focus on the type of information technology and findings that can be used to construct such environments and contexts to improve decision making. An additional objective is to help humans change their behavior to adapt to the context. For this purpose, the design of ambient intelligent systems is proposed in this study. Specifically, by integrating the concepts of “nudge” and “boost” in behavioral economics, we propose a method to design “nudge & boost agents” that encourage users to change their behavior to adapt to a situation (nudge function) and foster individual decision-making skills (boost function). The nudge and boost agents are implemented on the basis of ambient intelligent systems based on previous human-agent interaction (HAI) research. In this paper, we describe the concept of these agents and the implementation of the system. Furthermore, based on the evaluation results, the effectiveness of the system is clarified.

The maximum physical range of horizontal human eye movement is approximately 45°. However, in a natural gaze shift, the difference in the direction of the gaze relative to the frontal direction of the head rarely exceeds 25°. We name this region of 25° − 45° the “Kuiper Belt” in the eye-gaze interaction. We try to utilize this region to solve the Midas touch problem to enable a search task while reducing false input in the Virtual Reality environment. In this work, we conduct two studies to figure out the design principle of how we place menu items in the Kuiper Belt as an “out-of-natural angle” region of the eye-gaze movement, and determine the effectiveness and workload of the Kuiper Belt-based method. The results indicate that the Kuiper Belt-based method facilitated the visual search task while reducing false input. Finally, we present example applications utilizing the findings of these studies.

“Angels and Devils” express a human’s dilemma. In this paper, we produced this expression with multiple robots and investigated how humans change their decision and behavior in a moral dilemma environment. We divided the participants into Neutral-Neutral and Angel-Devil robot groups and investigated the willpower of the two groups by the alphabet writing task. We also examined the impression of the robots by Godspeed questionnaires and the results of the questionnaire.

Abstract

Emotional expressions are essential in augmenting a robot’s expression. Many robots with limited facial expression freedom, such as the Nao robot, can effectively express emotions using body movement. Previous studies have used a single robot and evaluated its expression. Multiple robots expressing emotion in their interactions may have a greater impact than robots expressing emotion only when interacting with humans. The relationships between these robots should allow them to develop more diverse modes of expression. However, it is unclear how people perceive relationships by observing robots’ emotional expressions. In this study, we applied every combination of four characteristic body emotion expressions (Sadness, Fear, Pride, and Happiness) based on Russell’s circumplex model to robots. Furthermore, we investigated how the relationships were evaluated in an online video-based experiment. The results show that the relationships between the two robots are influenced by each robot’s body emotional movement and can be interpreted using the valence-arousal model.

“Angel and Devil” expression has been used to cause a dilemma in various animations and comics. In this video demo, we implemented this expression with multiple robots. We supposed a scene in daily life, a student carrying a backpack and two robots riding on both shoulders to encourage the student to make decisions. This research concept can be the novelty use case of personal AI robots. In future works, the decision-making methodologies suggested by behavioral economics, such as nudging and boosting, can adopt to human-robot interaction by using multiple robots.

A variety of chatbots were developed to elicit people’s emotional responses and manage the emotions of people. These chatbots often use text-based emotional sentences. However, there are few studies that chatbots use extremely simplified communications to induce some emotional responses. We investigated the effect of mood contagion and tried to induce positive or negative words from people on our web-based ”word chain game” system as the most simplified conversational style. We also defined the system’s emotion as making the system use words that have polarity, which means each word’s strength of positive or negative emotion. The result shows that users of the system using positive words were slightly influenced to use more positive words than the neutral or negative system.

We conducted two studies exploring how an area cursor technique can improve the eye-gaze interface. We first examined the bubble cursor technique. We developed an eye-gaze-based cursor called the bubble gaze cursor and compared it to a standard eye-gaze interface and a bubble cursor with a mouse. The results revealed that the bubble gaze cursor interface was faster than the standard point cursor-based eye-gaze interface. In addition, the usability and mental workload were significantly better than those of the standard interface. Next, we extended the bubble gaze cursor technique and developed a bubble gaze lens. The results indicated that the bubble gaze lens technique was faster than the bubble gaze cursor method and the error rate was reduced by 54.0%. The usability and mental workload were also considerably better than those of the bubble gaze cursor.

In sports, studies commonly use agents as coaches or partners for motivation. However, despite the proven positive effect of cheering on athletes? mental state in the field of sports psychology, no studies have examined the effects of agent-based motivation. Hence, we created three scenarios: computer graphics animation (CG) and voice agent cheering,voice agent cheering, and no cheering and conducted experiments under their conditions. The experiment questionnaire results showed that ?CG and voice agent cheering? was more effective in novice participants than no cheering, confirming the former's positive effect on motivation.

The way a smart house system interacts with the user could limit the full potential a smart house is capable to provide, and an agent-mediated interface has been proved to broaden users' mental models. We designed four different conceptual smart house interfaces and surveyed to find out what kind of agent interface is desired under a wide variety of smart house needs.

As voice recognition technology develops, we talk to smart speakers and other voice assistants more and more frequently in everyday life. Many such speech dialog systems are designed to use honorifics. However, humans do not always use honorifics in everyday conversation. Thus, we consider that voice assistants need to use other forms of expression in addition to so-called polite language. In this study, we conducted a comparative experiment to investigate how the speaking styles of smart speakers affect human listeners. In this experiment, a participant talked to a smart speaker to make travel plans. We analyzed the results of questionnaires. We found that a smart speaker's friendly speaking style influenced the participants' impressions and thus shaped the development of good relationships between humans and agents. Our findings indicate that people regard agents as friends if they speak in a friendly manner.

We modeled a robot's approaching behavior for giving admonishment. We started by analyzing human behaviors. We conducted a data collection in which a guard approached others in two ways: 1) for admonishment, and 2) for a friendly purpose. We analyzed the difference between the admonishing approach and the friendly approach. The approaching trajectories in the two approaching types are similar; nevertheless, there are two subtle differences. First, the admonishing approach is slightly faster (1.3 m/sec) than the friendly approach (1.1 m/sec). Second, at the end of the approach, there is a `shortcut' in the trajectory. We implemented this model of the admonishing approach into a robot. Finally, we conducted a field experiment to verify the effectiveness of the model. A robot is used to admonish people who were using a smartphone while walking. The result shows that significantly more people yield to admonishment from a robot using the proposed method than from a robot using the friendly approach method.

We present an indoor navigation system, SCAN, which displays the user's current location on a user-scanned indoor map. Smartphones use the global positioning system (GPS) to determine their position on the earth, but it does not work in interior environments. SCAN uses indoor map images scanned by a smartphone camera and displays the user's position on the indoor map while they move around a floor. It tracks the user's position using an inertial measurement unit (IMU) on the smartphone. Camera calibration is required for precise navigation, but our system estimates the user's position based on a single landscape image. Results of our preliminary user study suggest that participants' experiences were similar to using outdoor GPS navigation systems.

We present an interactive 360-degree tabletop display system for collaborative work around a round table. Users are able to see 3D objects on the tabletop display anywhere around the table without 3D glasses. The system uses a visual perceptual mechanism for smooth motion parallax in the horizontal direction with fewer projectors than previous works. A 360-degree camera mounted above the table and image recognition software detects users' positions around the table and the heights of their faces (eyes) as they move around the table in real-time. Those mechanics help display correct vertical and horizontal direction motion parallax for different users simultaneously. Our system also has a user interaction function with a tablet device that manipulates 3D objects displayed on the table. These functions support collaborative work and communication between users. We implemented a prototype system and demonstrated the collaborative features of the 360-degree tabletop display system.

We present the MyoTilt target selection method for smartwatches, which employs a combination of a tilt operation and electromyography (EMG). First, a user tilts his/her arm to indicate the direction of cursor movement on the smartwatch; then s/he applies forces on the arm. EMG senses the force and moves the cursor to the direction where the user is tilting his/her arm to manipulate the cursor. In this way, the user can simply manipulate the cursor on the smartwatch with minimal effort, by tiling the arm and applying force to it. We conducted an experiment to investigate its performance and to understand its usability. Result showed that participants selected small targets with an accuracy greater than 93.89%. In addition, performance significantly improved compared to previous tilting operation methods. Likewise, its accuracy was stable as targets became smaller, indicating that the method is unaffected by the "fat finger problem".

We present new alternative interfaces for zooming out on a mobile device: Bounce Back and Force Zoom. These interfaces are designed to be used with a single hand. They use a pressure-sensitive multitouch technology in which the pressure itself is used to zoom. Bounce Back senses the intensity of pressure while the user is pressing down on the display. When the user releases his or her finger, the view is bounced back to zoom out. Force Zoom also senses the intensity of pressure, and the zoom level is associated with this intensity. When the user presses down on the display, the view is scaled back according to the intensity of the pressure. We conducted a user study to investigate the efficiency and usability of our interfaces by comparing with previous pressure-sensitive zooming interface and Google Maps zooming interface as a baseline. Results showed that Bounce Back and Force Zoom was evaluated as significantly superior to that of previous research; number of operations was significantly lower than default mobile Google Maps interface and previous research.

Pets are humanity'V?stra G?talands oldest friend since ancient times. People have been living with them since then, and the relationship between people and pets as family members at home is well researched. Recently, social robots are entering family lives, and a new research field is being born, namely, a triad relationship between people, pets, and social robots. To investigate how a social robot affects a human-animal relationship in the home, an exploratory field experiment was conducted. In this experiment, a robot, called NAO, was introduced into the homes of 10 families, and 22 participants (with 12 pets:4 dogs and 8 cats), called 'owners' hereafter, were asked to interact with NAO. NAO was operated under two conditions:speaking positively to the pets, and speaking negatively to them. Just five sentenses that NAO spoke to the pets and two sentenses to the owners were different. The results of the study show that changing NAO's attitude to the pets affected both the owners? impression of the robot and the pet's impression of the robot (perceived by the owners).

In our research, we made a system in which a robot acquires motions from a human's motions and repeats the motion when the human communicates with the robot. By controlling the timing of the robot's imitation, we verified an effect of Mutual Adaptation between human and robot. As a result of the experiment in which we controlled the imitation timing, some experiment participants were influenced and changed their motion. We found in some cases the robot could affect human's motion by imitating that human's motion.

In this study, we investigate the effects of the emergence of joint attention in social interaction consisting of two robots and one person. Especially, we focus on synchronous behaviors of two robots and the degree of communication activity caused by their behaviors. We predict that when two robots communicate with each other using synchronous behaviors, the degree of communication activity between them is observed to become higher. Moreover, as a person close to two robots becomes easily involved in their communication, joint attention among them will emerge there when the robots turn their eyes to the person. For verifying this prediction, we conducted two experiments to investigate whether a direction of participants' eyes were guided by two robots' eyes and heads movements. Results of the experiments showed that when two robots gazed at a participant at the high degree of communication activity, the direction of his/her eyes was easily guided by two robots' eyes and heads movements.

In order to have simple conversations between users and companion robots, it is necessary that robots evaluate the user's attitude. We developed a robot behavior control system utilizing a user's skin conductance level (SCL). SCL is used as an indication of physiological arousal. This system controls the time the robot remains in one program based on the user's arousal level before changing topics. In the results, we found several tendencies of the user's response based on the SCL. We suggest a possibility for utilizing a user's physiological data to communicate with a robot.

For realizing smooth communication, participants' viewpoints and usages of demonstrative pronouns assume an important role. Moreover, they both are strongly associated and construct a dialogue structure among participants. In this study, we investigate the relation constructed by their viewpoints and usages of demonstrative pronouns in a small group. Especially, we conducted experiments to verify whether demonstrative pronouns were unified in a small group consisted of two participants and a robot guided by the robot, and evaluate participants' psychological factors on this occasion. As a result of experiments, the unification of demonstrative pronouns in the small group guided by the robot led participants to smooth communication.

Researchers have developed computer systems which interact with people by recognizing situations around people. On the other hand, people behave socially based on perceived relations with others, being aware of a gaze from others, public pressure from others, and so on. If the computer systems can recognize the social relation and manage/control it, a new interactive service will emerge by enhancing the social skill of people. Designing, visualizing, and simulating relations also prepare a new socially interactive environment for people. The workshop named "Augmented Sociality and Interactive Technology" discuss the technologies which can deal with social relations and augment the social behaviors of people. Moreover, the workshop discuss interactive services using the technologies of the augmented sociality.

Today, wearable devices such as Google Glass and SmartWatch are gathering attention. These devices can constantly support us by being worn on a daily basis. In contrast, although we can also find an increase of personal robots in daily life, "wearable robots" are not so prevalent. We focus on wearable robots and the "fixed" points on which they are worn. We believe that they can provide more continuous and suitable support in a variety of ways by moving automatically on our bodies. Therefore, we propose a daily support system with a wearable robot that moves on the body, and we developed a small prototype robot that can move on a rail fixed on a belt worn on the human body.

In this study, we investigate the two effects of joint attention, building relationships and sharing recognition, in group interaction consisting of two robots and one person. The building relationship is focused on entrainment resulting from the two robots' gazing at one person, while the sharing recognition refers to an original effect of the joint attention in a group interaction featuring the shared focus of individuals on one object. Results of experiments on the building relationships aspect showed that when two robots gazed at a person, he/she tended to be more immersed in communication with the robots. In the case of sharing recognition, when the two robots gazed at the target synchronously, the person could share it more correctly than when it was done asynchronously.

In recent years, devices such as smartphones have made it increasingly easier for people to capture videos and then share those videos on Social Networking Services. Shared videos are able of representing almost all emotional experiences, such as interest, astonishment and excitement. However, it is difficult for people who have little knowledge concerning professional video shooting to express these experiences using only video. To address this issue, we developed AffectiView -- a mobile video camera application that captures users' affective responses while they are capturing videos, and also provides a way for sharing that data with other users. In this System, affective responses are measured using physiological proxies. We have organized into three styles the representation of physiological signals between users found in prior works. This system provides video shooters' emotional experiences to viewers by applying each of these three styles to the captured video. A preliminary user study has revealed the positive effects of capturing and sharing physiological signals together with video.

In this paper we propose a model of context-adaptive imitation between multi-human and multi-robot. In this model, first, a humanoid robot extracts human's intention from his/her behaviors, utterances, and situations. Secondly, the robot communicates this intention not only to other robots through a network, but also to humans through the robot's body expressions. Thirdly, the robot who received the intention generates context-adaptive behaviors according to the situation. We implemented this robot system for a guided task for visitors using the architecture of situated modules. We discuss the validity and availability of the proposed model using the case-study of the guided task by the implemented robot system.

The first robotic copies of real humans have become available. They enable their users to be physically present in multiple locations at the same time. This study investigates what influence the embodiment of an agent has on its persuasiveness and its perceived personality. Is a robotic copy as persuasive as its human counterpart? Does it have the same personality? We performed an experiment in which the embodiment of the agent was the independent variable and the persuasiveness and perceived personality were the dependent measurement. The persuasive agent advertised a Bluetooth headset. The results show that an android is found to be as persuasive as a real human or a video recording of a real human. The personality of the participant had a considerable influence on the measurements. Participants that were more open to new experiences rated the persuasive agent lower on agreeableness and extroversion. They were also more willing to spend money on the advertised product.

In this paper we describe an ITACO system that is able to construct an emotional relationship between humans and interactive systems by a migratable agent. The agent in the ITACO system can migrate between interactive systems within an environment. We conducted psychological experiments to verify whether the ITACO system can construct an emotional relationship between humans and interactive systems such as a robot and a table lamp. The experimental results show that emotional relationships were constructed between humans and interactive systems. Thus emotional relationships gave an influence to human’s behavior and cognitive abilities.

In this research, we realize human telepresence by developing a remote-controlled android system called Geminoid HI-1. Experimental results confirm that participants felt stronger presence of the operator when he talked through the android than when he appeared on a video monitor in a video conference system. In addition, participants talked with the robot naturally and evaluated its human likeness as equal to a man on a video monitor. At this paper's conclusion, we will discuss a remote-control system for telepresence that uses a human-like android robot as a new telecommunication medium.

In late years, as new media turning into PC or mobile phone, a study about communication robots is prosperous. Robots are different from the conventional media, because robots have physical bodies like humans, so it is reported that humans bemust robots socially. Therefore, we decide to apply a concept of meme as a cultural gene to an interaction design with humans and robots in this study. By this design theory, we will realize Mimetic Mutual Adaptation by humans and robots imitating and adapting each other, exceeding a conventional form of oneway adaptation from humans to the media. Therefore, we called cultural information transmitted from robots "RobotMeme", we try that robots acquire cultural behaviors shared by human society and the robots transmits these meme to other robots by Human-Robot Mimetic Mutual Adaptation. Furthermore, we suggest "A Design of RobotMeme" to realize that robots create new cultural behaviors through human-robot interaction. In this paper, we describe an early stage of experiments to inspect whether RobotMeme were transmitted to human and observed that humans acquired original cultural behaviors of robots by imitation. From the results of these experiments, it is suggested that robots and human are going to be able to form the relations of interdependence by imitating each other.

With developments in robotics, robots "living" with people will become a part of daily life in the near future. However, there are many problems with social robots. In particular, the behavior of robots can influence human relations, and societies have not yet clarified this. In this paper, we report on an experiment we conducted to verify the influence of robot behavior on human relations using the "balance theory." The results show that robots can have both good and bad influence on human relations. One person's impression of another can undergo changes because of a robot. In other words, robots can construct or collapse human relations.

We propose a concept of Ubiquitous Cognition and introduce an integrated agent for communication (ITACO) system based on the concept. To realize our proposed concept, the ITACO system tries to appropriately support a user using a migratable agent which is context-sensitive and gives continuous assistance. The key factor in this system is the construction of a relationship between the user and the agent, and to carry on this relationship between the user and the object that the agent has migrated to. Psychological experiments were carried out to verify this succession of the relationship between media. The results of the experiments showed that the subjects' attachment to the media as well as the relationship was succeeded through the media by the agent migration.

Previous research works in robotics and cognitive science have reported that humans utilize embodied cooperative behaviors in communication, such as nodding in response to another's it utterance and looking at a certain object in a certain direction as others look or point at. We have developed a humanoid robot that utilizes such an embodied cooperative behavior for natural communication in a route guidance situation. It obtains numerical data on a human's body movement via a motion capturing system and then autonomously selects appropriate cooperative embodiment units from 18 implemented units. Each unit realizes a certain cooperative embodiment behaviors such as eye-contact by using the motion capturing system as well. As a result of a subject experiment, we have verified the effectiveness of the embodied cooperative behaviors of the robot for reliable and sympathetic communication. Moreover, we analyzed how the auditory expression and the embodiment contributed to the effect.

We report the development and evaluation of a new interactive humanoid robot that communicates with humans and is designed to participate in human society as a partner. A human-like body will provide an abundance of nonverbal information and enable us to smoothly communicate with the robot. To achieve this, we developed a humanoid robot that autonomously interacts with humans by speaking and gesturing. Interaction achieved through a large number of interactive behaviors, which are developed by using a visualizing tool for understanding the developed complex system. Each interactive behavior is designed by using knowledge obtained through cognitive experiments and implemented by using situated recognition. The robot is used as a testbed for studying embodied communication. Our strategy is to analyze human-robot interaction in terms of body movements using a motion-capturing system that allows us to measure the body movements in detail. We performed experiments to compare the body movements with subjective evaluation based on a psychological method. The results reveal the importance of well-coordinated behaviors as well as the performance of the developed interactive behaviors and suggest a new analytical approach to human-robot interaction.

In this paper, we report about a new interaction-oriented robot, which communicates with humans and will participate in human society as our partner. For realizing such a robot, we have started a new collaborative work between cognitive science and robotics. In the way of robotics, we have developed a humanoid robot named "Robovie" that has enough physical expression ability. On the other hand, through cognitive experiments, we obtained important ideas about the robot's body property. To incorporate these ideas, we have developed software architecture and implemented autonomous interactive behaviors to the robot. Further, we have evaluated the robot's performance of the interactive behaviors through psychological experiments. The experiments reveal how humans recognize the robot.

There is a strong correlation between the number of appropriate behaviors an interactive robot can produce and its perceived intelligence. We propose a robot architecture for implementing a large number of behaviors and a visualizing tool for understanding the developed complex system. Behaviors are designed by using knowledge obtained through cognitive experiments and implemented by using situated recognition. By representing relationships between behaviors, episode rules help to guide the robot in communicating with people in a consistent manner. We have implemented over 100 behaviors and 800 episode rules in a humanoid robot. As a result, the robot could entice people to relate to it interpersonally. An Episode Editor is a tool to support the development of episode rules and to visualize the complex relationships among the behaviors. We consider the visualization is to be necessary for the constructive approach.