Realization of flock behavior by using Tau-margin

Recently autonomous robot that is designed based on biological mechanism has attracted much attention. In this paper we focus on mechanism of timing control which is studied in ecological psychology, and we apply it for controlling of multi mobile robot. Simulations have been conducted and various flock behaviors have been realized. In addition, we have confirmed that by using two leader robots, separation of flock is also possible. We can conclude that it is possible to realize flock behaviors by using the timing control without information of distance. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Peer-to-peer sensor network system for a school temperature measurement system

In this paper, we propose the technique of sensor data mining by the peer-to-peer (P2P) network. The mechanism that it is possible to share on the P2P network is considered by receiving information from the sensor by the P2P application. A searching request for a sensor unit and mining the sensor data occurs on the P2P application. We applied the proposed technique to a school environment measurement system. In this system, sensor units are arranged on campus and a user can measure a room’s temperature and humidity. The temperature sensor and the humidity sensor are implemented in a microcomputer board that can connect to the Internet, and we define the microcomputer board as a sensor unit. We construct the P2P sensor network on which a PC accesses the sensor unit and the P2P application on its PC uploads on the P2P network. The P2P network can disclose sensor information after more advanced processing is given by thinking as a P2P application and not a sensor unit, but on the sensor unit and the PC. This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27, 2007     

Adaptive immunity based reinforcement learning

Recently much attention has been paid to intelligent systems which can adapt themselves to dynamic and/or unknown environments by the use of learning methods. However, traditional learning methods have a disadvantage that learning requires enormously long amounts of time with the degree of complexity of systems and environments to be considered. We thus propose a novel reinforcement learning method based on adaptive immunity. Our proposed method can provide a near-optimal solution with less learning time by self-learning using the concept of adaptive immunity. The validity of our method is demonstrated through some simulations with Sutton’s maze problem. This work was present in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Three-dimensional parallel Turing machines

Informally, the parallel Turing machine (PTM) proposed by Wiedermann is a set of identical usual sequential Turing machines (STMs) cooperating on two common tapes: storage tape and input tape. Moreover, STMs which represent the individual processors of a parallel computer can multiply themselves in the course of computation. On the other hand, during the past 25 years or so, automata on a three-dimensional tape have been proposed as computational models of three-dimensional pattern processing, and several properties of such automata have been obtained. We proposed a three-dimensional parallel Turing machine (3-PTM), and dealt with a hardware-bounded 3-PTM whose inputs are restricted to cubic ones. We believe that this machine is useful in measuring the parallel computational complexity of three-dimensional images. In this article, we continue the study of 3-PTM, whose inputs are restricted to cubic ones, and investigate some of its accepting powers. This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27, 2007     

Collaborative capturing, interpreting, and sharing of experiences

This paper proposes a notion of interaction corpus, a captured collection of human behaviors and interactions among humans and artifacts. Digital multimedia and ubiquitous sensor technologies create a venue to capture and store interactions that are automatically annotated. A very large-scale accumulated corpus provides an important infrastructure for a future digital society for both humans and computers to understand verbal/non-verbal mechanisms of human interactions. The interaction corpus can also be used as a well-structured stored experience, which is shared with other people for communication and creation of further experiences. Our approach employs wearable and ubiquitous sensors, such as video cameras, microphones, and tracking tags, to capture all of the events from multiple viewpoints simultaneously. We demonstrate an application of generating a video-based experience summary that is reconfigured automatically from the interaction corpus.

Printable phosphorescent organic light‐emitting devices

Abstract— A new approach to full‐color printable phosphorescent organic light‐emitting devices (P²OLEDs) is reported. Unlike conventional solution‐processed OLEDs that contain conjugated polymers in the emissive layer, the P²OLED's emissive layer consists of small‐molecule materials. A red P²OLED that exhibits a luminous efficiency of 11.6 cd/A and a projected lifetime of 100,000 hours from an initial luminance of 500 cd/m², a green P²OLED with a luminous efficiency of 34 cd/A and a projected lifetime of 63,000 hours from an initial luminance of 1000 cd/m², a light‐blue P²OLED with a luminous efficiency of 19 cd/A and a projected lifetime 6000 hours from an initial luminance of 500 cd/m², and a blue P²OLED with a luminous efficiency of 6.2 cd/A and a projected lifetime of 1000 hours from an initial luminance of 500 cd/m² is presented.     

High‐luminance 1.8‐mm‐pixel‐pitch CNT‐FED for ubiquitous color character displays

Abstract— A high‐luminance 1.8‐mm‐pixel‐pitch CNT‐FED for color character displays has been developed. The display panel has 32 × 256 color pixels, and the subpixel size is 0.6 × 1.8 mm. The display panel can provide good visibility when installed even in outdoor locations. The power consumption is low enough for the display to be battery driven. The practical application is the display of important messages regarding the evacuation from disaster areas, even under emergent no‐power conditions similar to the messages on vending machines.     

Hierarchies based on the number of cooperating systems of three-dimensional finite automata

The question of whether processing three-dimensional digital patterns is much more difficult than two-dimensional ones is of great interest from both theoretical and practical standpoints. Recently, owing to advances in many application areas, such as computer vision, robotics, and so forth, it has become increasingly apparent that the study of three-dimensional pattern processing is of crucial importance. Thus, the study of three-dimensional automata as a computational model of three-dimensional pattern processing has become meaningful. This article introduces a cooperating system of three-dimensional finite automata as one model of three-dimensional automata. A cooperating system of three-dimensional finite automata consists of a finite number of three-dimensional finite automata and a three-dimensional input tape where these finite automata work independently (in parallel). Those finite automata whose input heads scan the same cell of the input tape can communicate with each other, i.e., every finite automaton is allowed to know the internal states of other finite automata on the cell it is scanning at the moment. In this article, we continue the study of cooperating systems of three-dimensional finite automata, and mainly investigate hierarchies based on the number of their cooperating systems.     

Determination of time to contact using a compound eye sensor

Recently, many control methods for autonomous robots based on biological mechanisms have been studied. In particular, the concept of time to contact, called the tau-margin, which is studied in ecological psychology, has attracted considerable attention. In conventional studies, various approaches have been used for the determination of the tau-margin, and the tau-margin has been used for the timing control of mobile robots. However, in these studies, robots fitted with a light bulb have been used, and direct light from the bulb has been used to determine the tau-margin. It is impossible to apply conventional methods to robots that use indirect light for determining the tau-margin. Therefore, we have developed a compound eye sensor comprising photodiodes. We employ the framework of optical flow to detect objects, and determine the tau-margin from the apparent size of the detected objects and the temporal changes in size. To demonstrate the effectiveness of the developed compound eye sensor, we control a mobile robot using this sensor, and conduct experiments in which the robot has to avoid an oncoming object. The timing of the robot is controlled by using the tau-margin. We conducted experiments by using an actual robot, and found that the robot could avoid an oncoming object successfully. We concluded that it is possible to determine the tau-margin by using the compound eye sensor which we have developed.     

The stretch of C-terminal acidic amino acids of translational release factor eRF1 is a primary binding site for eRF3 of fission yeast

Translation termination in eukaryotes requires a codon-specific (class-I) release factor, eRF1, and a GTP/GDP-dependent (class-II) release factor, eRF3. The model of "molecular mimicry between release factors and tRNA" predicts that eRF1 mimics tRNA to read the stop codon and that eRF3 mimics elongation factor EF-Tu to bring eRF1 to the A site of the ribosome for termination of protein synthesis. In this study, we set up three systems, in vitro affinity binding, a yeast two-hybrid system, and in vitro competition assay, to determine the eRF3-binding site of eRF1 using the fission yeast Schizosaccharomyces pombe proteins and creating systematic deletions in eRF1. The in vitro affinity binding experiments demonstrated that the predicted tRNA-mimicry truncation of eRF1 (Sup45) forms a stable complex with eRF3 (Sup35). All three test systems revealed that the most critical binding site is located at the C-terminal region of eRF1, which is conserved among eukaryotic eRF1s and rich in acidic amino acids. To our surprise, however, the C-terminal deletion eRF1 seems to be sufficient for cell viability in spite of the severe defect in eRF3 binding when expressed in a temperature-sensitive sup45 mutant of the budding yeast, Saccharomyces cerevisiae. These results cannot be accounted for by the simple "eRF3-EF-Tu mimicry" model, but may provide new insight into the eRF3 function for translation termination in eukaryotes.