The Third Joint International Seminar on Applied Analysis and Synthesis of Complex Systems
|
|
| IIASA - Kyoto University The Third Joint International Seminar on Applied Analysis and Synthesis of Complex Systems |
| June 29-30, 2005 |
| International Institute for Applied Systems Analysis, Laxenburg, Austria |
The term information technology is a misnomer reflecting an outmoded engineering way of thinking technology. It has become increasingly clear that the real power of so-called information technology resides in its ability to assist in the semiotic control of people's life. The same is the case in the life sphere technologies. To the extent living beings are governed through biosemiotic integration biotechnology must develop skills in dealing with the biosemiotic dynamics of organisms. Thus while the new wave of biotechnology was initially very much focused on the gene level, development now points in the direction of more integrated levels of cellular or organismic semiotic functionality. The technological mingling with the semiotics of living systems is of course a much more powerful way of interacting with nature than simple chemical or gene technological intervention. Like all other technological innovations biosemiotic technology presents potential dangers as well as promises. By focusing on the dangers critiques tend to blind us to the ecological and health care prospects these technologies hold. It is argued, that biosemiotic technology offers an indispensable tool for the creation of a truly sustainable production system.
The overall purpose of this paper is to demonstrate the relevance of semiotics concepts to the analysis of intelligent control systems. Semiotics has only a minor impact on research within intelligent control or robotics. These areas are currently dominated by mathematical concepts of control theory and information processing concepts of artificial intelligence. This situation is unfortunate because the understanding of a complex control problem requires an analysis of the sign relations between sensory data and their meanings and the sign relations between the physical result of a control action and the intentions of control agents. These problems of sign interpretation inherent in all control situations are relevant for the design of automated controls and of the interaction between human operators and the automation. The relevance of semiotics to control problems is demonstrated by applying the semiotics of action developed by Charles Morris to various aspects of a control situation. We use Morris's definition of three dimensions of signifying that arises from a decomposition of an action into perceptual, appraisive and prescriptive stages. These distinctions identify types of knowledge that a control agent must have in order to cope with a control situation in the environment. Selected examples from the domains of robotics and process control are used to demonstrate that Morris semiotics of action is valuable for conceptual analysis of control situations and for systems design
We take the position that cognition and cognitive behavior in artifacts cannot be engineered, but instead is the process of development of an embodied agent through interaction with its environment, and manifests as effective action within that environment. Thus, the process of "knowing" or cognition is effective action, and we are uniquely described by our history of structural coupling with our environment, including the social environment. The importance of the social aspects of the environment for the development of human cognition cannot be overstated. It may be that human-like intelligence could not be possible without the social environment, and that important characteristics of human-intelligence such as language are a direct consequence of social intelligence. In this talk I will present an architecture for an interaction history that has at its heart a metric space of grounded sensorimotor agent-centred experience. Experiences that are close in terms of their Shannon information content are placed near to each other in this space, and by directing action based on this space while also modifying it as a result of action, an artificial agent can develop in its capabilities for effective action for the environment it is embedded in. I will also present a series of experiments that has a robot engaging, with a human partner, in the simple interaction game "peekaboo" usually played by adults with infants. The robot through its interaction history develops interactive behavior based on past experience, directed by an underlying motivational landscape.
The regulatory process of mechanical adaptation of bone produces flow of interstitial fluid in the lacunar-canalicular network along the surface of osteocytes, which is likely the physiological signal for bone cell adaptive responses in vivo. As a result, the maintenance of a mechanically efficient architecture is likely to depend on a balance between the intensity and spatial distribution of the mechanical stimulus and the responsiveness of the bone cells. In addition, the alignment of secondary osteons along the dominant loading direction suggests that bone remodeling is guided by mechanical strain. We propose that alignment during remodelling occurs as a result of different canalicular flow patterns around cutting cone and reversal zone during loading. The response of cultured bone cells to fluid flow includes increased nitric oxide and prostaglandin synthesis which are involved in cellular mechanotransduction. These studies have increased our understanding of the cell biology underlying Wolff's Law. This may lead to new strategies for combating disuse-related osteoporosis, and to understanding and predicting the long-term integration of bone-replacing implants.
To understand mechanosensing by bone cells, a physical portrait of cell viscoelasticity is required. Thus, we developed an in vitro assay for two-particle microrheology to characterize the viscoelasticity and probe the mechano-activity of single MLO-Y4 osteocytes under round suspended morphology. The cells were suspended in cell culture medium and assumed a round morphology. These cells were then attached with fibronectin-coated spheres at opposite ends using optical tweezers. The elastic modulus of round suspended MLO-Y4 osteocytes was below 1kPa, as well as for MC3T3-E1, and primary bone cells. The fluctuation of force <ff*> induced by all cell types on the probes was proportional to ω-2 (where frequency = ω/(2π)), which is a signature for slowly evolving intracellular processes. These results demonstrate microrheology as tool for understanding mechanosensing by cells. By quantifying the mechanical properties of single bone cells, our results provide novel implications on the osteogenic response of bone to mechanical loading.
Animals behave adaptively in diverse environments. Adaptive behavior, which is one of the intelligent sensory-motor functions, is disturbed in patients with neurological disorders. However, the mechanisms for the generation of intelligent adaptive behaviors are not thoroughly understood. Such an adaptive function is considered to emerge from the interaction of the body, brain, and environment, which requires that a subject acts or moves. Therefore, the intelligence for generating adaptive motor function is called mobiligence. The present project is designed to investigate the mechanisms of mobiligence by collaborative research in biology and engineering.
One of the common interests in interdisciplinary academic areas is on the reconsideration about the mutual and inseparable relationships between the external environment and the internal of the agent that is an actor, an observer, a cognizer, and an interpreter. We introduce the subject of semiotics, a new interdisciplinary branch of science, and its potential contribution to bridging between the biological intelligence and machine intelligence. Our developing new concept of Soft Dynamical Systems is putting an emphasis on its biologically-inspired architecture that can accommodate the flexible and dynamic capabilities of living systems including a human. That is, it has to be able to grow and develop increasing capabilities of self-control, self-awareness of representation and reasoning about self and of constructing a coherent whole out of different representations. Actually, a new branch of research on artificial life and system theory of function emergence has shifted the perspectives of intelligence from the conventional reductionism into a new design principle based on the concept of "emergence". That is, their approach is quite new in that they attempt to build models which bring together self-organizing mechanisms with evolutionary computations. Such a trend has forced us to reconsider about the biological system and/or natural intelligence. In this talk focusing on the aspects of semiosis, a constructive approach to semiotics are presented. Then, we discuss about the design principle for a joint system, which consists of an external environment, a human and a machine, self-organize their distinctive roles in a bottom-up and emerging fashion.
Human locomotion system has `pull-in effect', in which if the ground swings with specific frequencies in one's frontal plane, a human's gait rhythm changes into the ground swinging frequency from one's natural gait rhythm. However the cause of the effect is still not clear. This paper notices human's posture controlling system, and refers to the cause of pull-in effect with suggesting a dynamical human gait model which has two legs and posture controller. Firstly the features of pull-in effect are clarified experimentally and secondly the posture controller which works for stabilizing frontal body behavior is studied. Then a dynamical human gait model is established from the results. The model consists of two beams and a mass representing legs and center of gravity of one's body. It basically behaves passively, but only the posture is controlled actively. The model shows the features of pull-in effect very well, and looking at the behavior of the model, it is explained that the posture controller causes pull-in effect.
As living tissue maintains its shape and function by adaptive self-remodeling, it is difficult to design an artificial shape and a function in the body. Our theme is the "in-vivo environment designing" which is the key factor for successful tissue-engineering treatment. Several biological, clinical and mathematical approaches to the "in-vivo environment designing" will be introduced in the presentation. We want to discuss how to design the proper environments and how to control the shape and the function of living tissues, especially with respect to the following issues;
In bone functional adaptation by remodeling, osteocytes in lacuno-canalicular system are believed to play important roles in the mechanosensory system. Under dynamic loading, the bone matrix deforms and its stress/strain field generates flow in the lacuno-canaliclar system. The fluid flow induces shear stress on the cell process membrane, that is known to stimulate the osteocytes. In this sense, the osteocytes behave as mechanosensors and deliver its mechanical information to the neighboring cells through the intercellular communication. In this study, bone remodeling is assumed to be regulated by the mechanical information collected by the osteocytes. From the viewpoint of multiscale biomechanics, we proposed a rate equation for the trabecular bone remodeling considering the lacuno-canalicular network system. The characteristics of the system were taken into account in the rate equation as anisotropic sensitivity to the macroscopic pressure gradient. Based on the proposed rate equation, a computational simulation for trabecular bone remodeling was conducted for a single trabecula under compressive loading, demonstrating the functional adaptation to the applied mechanical loading.
Bone remodels its structure adaptively to the surrounding mechanical environment. The network system formed by bone cells known as osteocytes embedded in bone matrix is considered as one of the important elements for the bone remodeling phenomenon. However, the detailed mechanism of mechanosensing and cellular communication in osteocyte network system has not been clearly understood. The relation between macroscopic mechanical stimulation to bone matrix and microscopic response of osteocyte network system is also unknown. In the present study, we observed the calcium signaling response of osteocytes isolated from and embedded in living bone tissue matrix to mechanical stimulation. The changes of the intracellular Ca2+ concentration, which is indicated by fluorescent dye: Fluo4-AM and Fura Red-AM, were observed by a confocal laser-scanning microscopy. The direct deformation was locally applied to isolated osteocytes and living bone tissue matrices by the microneedle. From the engineering viewpoint, this study is placed as a first step to realize artificial materials with smart functions, such as self-diagnosis, self-repairing and environmental adaptation, by imitating the adaptive bone remodeling mechanism.
Applying conventional multivariate statistical analysis methods or modern data mining approaches simply to a manufacturing database does not always provide sufficient knowledge for revealing the key factors of chronic defects and how they cause the defects, especially in a complex production system. As an interface between such a production system and engineers who should plan how to improve manufacturing quality in the system, this research project proposes an explorative data analysis framework named the multi-stage quality information model (MSQIM). It should establish some hypotheses, if possible, on the causal factors and/or the defect-causing mechanisms, and should at least identify which process steps within the production system further efforts of causal factor detection should be focused on. MSQIM first divides a manufacturing database into several segments, each of which corresponds to a certain process step within the production system. It then traces how the amount of information on the resultant manufacturing quality varies along the process steps so as to identify the relevant process steps that require further focus. The varying pattern of the quality information is also studied in a qualitative way so that it assists in hypothesis generation.