The fuzzy sets theory has provided a new direction to design process controls by multi-model approach. This paper proposes a new method to build operator models for process controls by means of the hyperellipsoidal clustering method that becomes the focal point of fuzzy modeling. The clustering algorithm combines hierarchical and non-hierarchical procedures, and does not require a priori assumption on the number, centroids, and volumes of clusters. An application study under consideration is the stable incineration control of a rotary kiln process treating excess sludge from a municipal wastewater treatment plant.
We are studying virtual reality system for “Hyper Hospital”. The “Hyper Hospital” is a medical care system which is distributedly constructed on an electronic information network. In the present report, we discussed a new version of our virtual reality system using a head-position sensor by the ultrasound, and a new head mounted display as the hardware parts of the system. We also developed an object oriented software to construct the virtual world for the Hyper Hospital. For severely disabled patients, we are studying the feasibility of the ERP (event related potential of the electroencephalogram) based human interface. The prototype system of the “Hyper Hospital” developed in the present study was shown to be applicable to the real medical environment.
We proposed a novel concept of the on-line hospital system using a virtual reality called “Hyper Hospital”. For making the “Hyper Hospital” come true, it is important to investigate the effect of the virtual reality system (V. R. system) on the human body. In this experiment, twenty healthy young male subjects were exposed to our own V. R. system and their circulatory and respiratory function including blood pressure, ECG, pulse wave, etc., were recorded for 35 minutes. Results showed that the subjects did not experience strong effects on their circulatory and respiratory function by the V. R. system.
Urinary catecholamine release and pH of saliva was measured to detect the fatigue induced by application of the virtual reality (VR) used as a human interface of the Hyper Hospital-a network based virtual reality mediated medical care system. After the usage of the VR for 30 minutes, none of three types of catecholamines (Epinephrine, Norepinephrine, and Dopamine) nor pH of saliva increased significantly. It was therefore concluded that fatigue by the 30 minutes loading of the VR is not detectable in terms of the urinary catecholamine release and of pH of saliva.
We are studying the virtual reality which is used as mean of human interface between the patients and the Hyper Hospital-a network based virtual reality mediated medical care system. For making the Hyper Hospital come true, it is important to investigate the effect of the virtual reality system (V. R. system) on the human body. In the present study, twenty healthy young subjects underwent the physiological measurements while using our own head mounted display (HMD). We measured the auditory response time which is regarded as a measure of a net activity of the central nervous system and is known to be affected by many physiological conditions such as fatigue. We also measured the critical flicker frequency (CFF) values before, during, and after the application of the V. R. system. The psychological fatigue was measured quantitatively by standard questionnaires and the Kraepelin test. The Yatabe-Guilford (YG) test was also carried out to investigate the influence of the individual character on the psychological fatigue. Some discomforts were complained after 30 minutes use of our HMD by almost all of the subjects. Examination of the CFF values did not show any significant changes due to the application of the V. R. system. No statistically significant difference was found by the usage of the V. R. system. The subjective fatigue measured using a standard questionnaires suggested that psychological fatigue was more significant than physical fatigue. No significant correlations were found between the result of the Kraepelin test and the individual character measured by YG test. No statistically significant fatigue was found by the usage of the V. R. system, and it was therefore suggested that the short time application of the V. R. system does not affect the human neurological and psychological response.
The shear stress over cultured endothelial cells was conventionally estimated assuming a flat cell surface by most of previous authors. This assumption is not true, if the cells are observed closely. Therefore we evaluated the surface shear stress distribution using computational fluid mechanics in the present study. Results of this study showed that, the peak value of the shear stress on the top of the cell over the underlying nucleus (nuclear bulge) sometimes became several times larger than that of the flat part of the cell surface. Also noted was that the gradient of the surface shear stress was high along the side of the nuclear bulge. These findings may suggest the existence of a preferred location of a shear stress sensing apparatus on the cell surface.
Platinum and its alloys which own excellent characteristics such as corrosion resistance, high melting point, heat resistance and so on are widely used for industry, for example, ammonia oxidation catalyst gauzes, thermocouples, temperature measuring resistance bulb, However, the fundamental data at high temperature are not enough, In this report, the tensile strength and elongation of Platinum-Rhodium alloys in the range of temper-ature 100-600°C are examined and then compared with those of Platinum.
During preparation of microstructure, often refered to as cutting, mounting, grinding and polishing, the structure may be influenced to such a degree, that the subsequent examinationin the mictoscope can show incorrect results. In general, it is believed, that as long as the surface appears shiny and reflective without scratches, the preparation is OK, but the real life shows, that this may not always be correct. This paper describes an alternative approach.
Amorphous structure has been investigated from not only the topological viewpoint but also the chemical one. Especially, the neutron diffraction allows one to observe directly the concentration-concentration correlation functions of the neutron zero scattering amorphous alloys. The chemical short-range order (CSRO) of Ti-Cu and Ti-Ni neutron zero scattering amorphous alloys differs from each other, even though Ni, being located next to Cu in the Periodic Table, has an atomic size which is almost the same as that of Cu. The CSRO of Ti-Ni-Cu ternary neutron zero-scattering amorphous alloys is found to increase rapidly with increasing Ni content. The results indicate that an increase of the CSRO by alloying with Ni element is ascribed to the stronger affinity of a Ni atom with a Ti atom than that of a Cu atom. Moreover, the CSRO strongly affects with the thermal properties, i.e., the crystallization temperature and the enthalpy of crystallization.
The high speed impact method for the surface modification of particles, called the NARA Hybridization System, is one of the most highlighted one among the methods for developing various particles. The key machine which joins many fine powder to the surface of a core particle through a dry and mechanical method can be used to various industries because it is highly flexible in each process and covers many kinds of substances, such as organic, inorganic and metallic materials. We describe the basic features of this hybridization system in connection with their construction, operational characteristics and applications.