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31.
Makoto Sakamoto Kaoru Kajisa Naoko Tomozoe Takao Ito Hiroshi Furutani Michio Kono Satoshi Ikeda 《Artificial Life and Robotics》2008,13(1):61-64
In 1997, C.R. Dyer and A. Rosenfeld introduced an acceptor on a two-dimensional pattern (or tape), called the pyramid cellular acceptor, and demonstrated that many useful recognition tasks are executed by pyramid cellular acceptors in time proportional to the
logarithm of the diameter of the input. They also introduced a bottom-up pyramid cellular acceptor which is a restricted version of the pyramid cellular acceptor, and proposed some interesting open problems of the bottom-up
pyramid cellular acceptors. On the other hand, we think that the study of threedimensional automata has been meaningful as
the computational model of three-dimensional information processing such as computer vision, robotics, and so forth. In this
paper, we investigate about bottom-up pyramid cellular acceptors with three-dimensional layers, and show their some accepting
powers.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
32.
Norman Makoto Su Hiroko N. Wilensky David F. Redmiles 《Computer Supported Cooperative Work (CSCW)》2012,21(2-3):111-162
We explore how the notion of communities of practice (CoPs) was translated and popularized from its original inception by Lave and Wenger in 1991. We argue that the Institute for Research on Learning (IRL), a spin-off of Xerox PARC, proved instrumental in enrolling CoPs into the knowledge management (KM) discipline. IRL objectified, packaged, and made a business out of CoPs. CoPs in KM are now a formalized process coupled with technological artifacts to build groups of people who effectively share knowledge across boundaries. Drawing from participant observations, archival documents, and interviews with KM practitioners in the aerospace industry as well as key players of IRL, our research seeks to unveil the invisible history that the popularization of a theory can often obscure. We argue that CoPs provide a case study for understanding how abstract concepts in science are strategically and subconsciously reified, or made objects of inquiry, and appropriated by actors. This reification of a “soft” science blurs the line between theory and technology. 相似文献
33.
Summary
Copolymerization of vinyl chloride (VC) and ethylene with Cp*Ti( OCH3)3/MAO catalyst was investigated. The Cp*Ti( OCH3)3/MAO catalyst initiated the copolymerization of VC with ethylene, although the copolymer yields were low. In the 13C NMR spectra of the copolymers, the peaks based on junction part between VC and ethylene was observed, but the signals were
small. From DSC measurement of the copolymers, only one glass transition temperature was observed. Thus, it is clear that
the copolymerization with Cp*Ti( OCH3)3/MAO catalysts gave the copolymer, and the copolymer consisting of block sequence rather than random copolymer.
Received: 13 November 2002/Revised: 6 January 2003/Accepted: 10 January 2003
Correspondence to Kiyoshi Endo 相似文献
34.
Toru Yamaguchi Makoto Sato Tomohiro Takagi 《Journal of Intelligent and Robotic Systems》1998,23(2-4):183-199
This paper proposes a multi-agent system that carries out cooperative work. To achieve this, we use Fuzzy Associative Memory Organizing Unit Systems (FAMOUS) and Conceptual Fuzzy Sets (CFS). By using these proposed methods, each agent robot can decide its own behaviour to suit the situation in its environment. We apply this system to an Intelligent Transportation System (ITS) and do simulations. 相似文献
35.
Sensor Fusion System Using Recurrent Fuzzy Inference 总被引:1,自引:0,他引:1
Futoshi Kobayashi Fumihito Arai Toshio Fukuda Koji Shimojima Makoto Onoda Norimasa Marui 《Journal of Intelligent and Robotic Systems》1998,23(2-4):201-216
In robotic and manufacturing systems, it is difficult to measure the state of systems accurately because of many uncertain factors and noise, and it is very important to estimate the state of systems. We must measure the phenomena of systems by multiple sensors and estimate the state of systems by acquiring information of sensors. However, we can not acquire all of sensor information synchronically, because each sensor has particular sensor information and measuring time. For estimating the state of systems by multiple sensors, a multi-sensor fusion system fusing various sensory information is needed. In this paper, we propose a Recurrent Fuzzy Inference (RFI) with recurrent inputs and apply it to a multi-sensor fusion system for estimating the state of systems. The membership functions of RFI are expressed by Radial Basis Function (RBF) with insensitive ranges. The shape of the membership functions can be adjusted by a learning algorithm. The learning algorithm is based on the steepest descent method and incremental learning which can add new fuzzy rules. The effectiveness of the multi-sensor fusion system using RFI will be shown through a numerical experiment of moving robot and estimation of surface roughness in grinding process. 相似文献
36.
Makoto Kobayashi Masashi Shimada Yuji Hatano Takuji Oda Brad Merrill Yasuhisa Oya Kenji Okuno 《Fusion Engineering and Design》2013,88(9-10):1749-1752
The deuterium trapping behaviors in tungsten damaged by light ions with lower energy (10 keV C+ and 3 keV He+) or a heavy ion with higher energy (2.8 MeV Fe2+) were compared by means of TDS to understand the effects of cascade collisions on deuterium retention in tungsten. By light ion irradiation, most of deuterium was trapped by vacancies, whose retention was almost saturated at the damage level of 0.2 dpa. For the heavy ion irradiation, the deuterium trapping by voids was found, indicating that cascade collisions by the heavy ion irradiation would create the voids in tungsten. Most of deuterium trapped by the voids was desorbed in higher temperature region compared to that trapped by vacancies. It was also found that deuterium could accumulate in the voids, resulting in the formation of blisters in tungsten. 相似文献
37.
TAR DNA binding protein 43 (TDP-43) is a DNA/RNA binding protein involved in pivotal cellular functions, especially in RNA metabolism. Hyperphosphorylated and ubiquitinated TDP-43-positive neuronal cytoplasmic inclusions are identified in the brain and spinal cord in most cases of amyotrophic lateral sclerosis (ALS) and a substantial proportion of frontotemporal lobar degeneration (FTLD) cases. TDP-43 dysfunctions and cytoplasmic aggregation seem to be the central pathogenicity in ALS and FTLD. Therefore, unraveling both the physiological and pathological mechanisms of TDP-43 may enable the exploration of novel therapeutic strategies. This review highlights the current understanding of TDP-43 biology and pathology, describing the cellular processes involved in the pathogeneses of ALS and FTLD, such as post-translational modifications, RNA metabolism, liquid–liquid phase separation, proteolysis, and the potential prion-like propagation propensity of the TDP-43 inclusions. 相似文献
38.
Koji Ishiguro Yoto SameshimaTakashi Kume Ken-ichiro IkedaJun Matsumoto Makoto Yoshimoto 《Food chemistry》2012,131(3):774-779
We have investigated angiotensin I-converting enzyme (ACE) inhibitory activity in an enzyme digest of sweetpotato protein, the antihypertensive effect of the digest in spontaneously hypertensive rats (SHR), and the identification of an ACE inhibitory peptide. Protein was prepared from squeezed juice of sweetpotato by isoelectric focusing precipitation. Three kinds of proteases were selected for effective protein digestion. The digest, sweetpotato peptide (SPP), exhibited strong ACE inhibitory activity (IC50: 18.2 μg/ml). SPP was orally administered by gavage to SHR at a dose of 100 mg/kg or 500 mg/kg. The systolic blood pressure and the diastolic blood pressure were measured at 0 (before administration), 2, 4, 8, and 24 h after administration. A dose-dependent decrease in systolic blood pressure in SHR was observed after oral administration of SPP. Significant differences between SPP-administered rats and control rats were observed 4 and 8 h after administration in the 500 mg/kg-administered group and 8 h after administration in the 100 mg/kg-administered group. Diastolic blood pressure also decreased in the SPP-administered groups, although the difference between SPP-administered rats and control rats was not significant. These results suggest that SPP may be useful in the prevention or treatment of hypertension. Peptides with ACE inhibitory activity were purified from SPP by absorption chromatography and preparative HPLC using an ODS column. The amino acid sequences of isolated peptides were I-T-P, I-I-P, G-Q-Y and S-T-Y-Q-T; their ACE inhibitory activities (IC50) were 9.5 μM, 80.8 μM, 52.3 μM and 300.4 μM, respectively. In conclusion, I-T-P is a novel, strong ACE inhibitory peptide. 相似文献
39.
40.
Yasuhiro Shimizu Elisabetta Di Bartolomeo Enrico Traversa Gualtiero Gusmano Takeo Hyodo Kenji Wada Makoto Egashira 《Sensors and actuators. B, Chemical》1999,60(2-3):118-124
NO2 sensing properties of SnO2-based varistor-type sensors have been investigated in the temperature range of 400-650°C and in the NO2 concentration range of 15–30 ppm. Pure SnO2 exhibited a weak nonlinear I–V characteristic in air, but clear nonlinearity in NO2 at 450°C. The breakdown voltage of SnO2 shifted to a high electric field upon exposure to NO2 and the magnitude of the shift was well correlated with NO2 concentration. Thus, SnO2 exhibited some sensitivity to NO2 as a varistor-type sensor. When SnO2 particles coated with a SiO2 thin film were used as a raw material for fabricating a varistor, the breakdown voltage in air was approximately the double that of pure SnO2 and the sensitivity to 15 ppm NO2 was enhanced slightly. However, the sensitivity to 30 ppm NO2 decreased. The Cr2O3-loading on SnO2 also led to an increase in the breakdown voltage in air, but the Cr2O3 addition was not effective for promoting the NO2 sensitivity under the present experimental conditions. 相似文献