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ABSTRACT: This paper proposes a method to build an individual hand model that consists of a surface skin and an inside link model, which can be used to reconstruct hand behavior from motion capture (MoCap) data. Our system uses a static posture data, a palmar side photo and marker positions captured simultaneously by MoCap, to reduce extra time and effort demanded for each subject to build a model. From this modeling scan, several hand dimensions and marker positions are obtained. Joint centers are estimated based on regression analysis about joint centers, marker positions and some hand dimensions derived from magnetic resonance (MR) images of eight subjects. The skin surface is built by scaling a generic hand model so that it satisfies the measured dimensions. The proposed system will be validated through an experiment to build four subjects' hand models.
Robotics and Automation (ICRA), 2011 IEEE International Conference on; 06/2011
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ABSTRACT: This paper presents a novel initial value compensation (IVC) methodology considering rolling friction properties for the fast and precise positioning. Rolling friction in mechanism behaves as a nonlinear elastic element in the micro displacement region, and deteriorates the positioning performance with the slow settling response. In order to improve the performance, a rolling friction model-based feedforward friction compensation is one of promising approaches. However, in the case that the friction model error exists, the model-based compensation approach can not achieve the desired position response during the transient response, resulting in the deterioration of the settling performance with the response variation and the slow response. In this paper, therefore, an IVC using the specified step settling control framework is applied to achieve the required settling performance without the deterioration. Since the proposed IVC can compensate for the effects of the feedforward friction compensation errors during the transient, the overshoot response, which causes the slow settling response, can be suppressed at the settling. The proposed IVC has been verified by experiments using a prototype of linear motor-driven industrial positioning devices.
IECON 2010 - 36th Annual Conference on IEEE Industrial Electronics Society; 12/2010
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ABSTRACT: With more applications coming to rely on high-speed access to the Internet, bringing broadband connectivity to residences and businesses as well as to mobile terminals is growing in importance. Yet, year after year, the data collected by the Organization for Economic Cooperation and Development (OECD) have shown that, among the developed countries, those with a large urban population such as South Korea, Japan, France and the Netherlands are more likely to achieve a higher rate of broadband penetration than those with significant rural communities such as the United States and Canada [1]. Figure 1 plots the data series in Table 1, which represents the broadband penetration per 100 inhabitants vs. the percentage of total landmass used by 50 percent of the population for various OECD countries.
IEEE Communications Magazine 11/2010; · 3.79 Impact Factor
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ABSTRACT: This paper presents the relationship between the dynamic characteristics and sampling frequency of digitally controlled dc-dc converter with a novel control method. In the proposed method, the calculation process of P and I-D controls is parallel. The sampling interval and points for I-D control are same to the conventional method. However, the sampling point for P control is quickly. The AD converter can sample the output voltage during the short interval because the calculation process of P control is very simple and to important for transient response. The only sample data near the turn-off timing of PWM pulse is used. The simulation and experiment results of the output voltage against the step change of the load and changing the P control sampling frequency are discussed. As a result, it is revealed experimentally that the good transient response is obtained.
Power Electronics Electrical Drives Automation and Motion (SPEEDAM), 2010 International Symposium on; 07/2010
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ABSTRACT: This paper presents a rolling friction model-based friction compensation in the precise positioning of linear motor-driven table systems. The rolling friction in mechanisms behaves as a nonlinear elastic element in the micro displacement region and deteriorates the positioning performance due to slow settling responses. In this research, therefore, the rolling friction characteristic is mathematically formulated to examine the slow responses in the settling region, and the rolling friction model is adopted to controller design to improve the settling performance. In the analytical examinations, a rheology-based rolling friction model is introduced to construct a precise simulator and clarifies the mechanism of the slow settling response. In the compensator design, on the other hand, the rolling friction model is adopted to a friction compensator to suppress effects of the rolling friction on the precise positioning at the settling region. The proposed examinations and friction compensation for the slow settling response have been verified by simulations and experiments using a prototype of industrial positioning devices.
Advanced Motion Control, 2010 11th IEEE International Workshop on; 04/2010
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ABSTRACT: This paper presents an initial friction compensation by a disturbance observer in the fast and precise positioning of ball screw-driven table systems, on the basis of a rolling friction model. The rolling friction behaves as a nonlinear elastic element in the table drive mechanism, especially in the micro-displacement region, deteriorating the fine positioning performance. Effects of the rolling friction on the positioning, therefore, should be compensated to achieve the desired control performance. In the controller design, a feedback control with a disturbance observer allows the plant system to behave as a nominal one with robust stability, and compensates for effects of nonlinear friction on the positioning performance. However, the disturbance observer has an estimation delay for the initial friction behavior at the starting motion in positioning due to a low pass filter and delay components. In this paper, therefore, a rolling friction model is adopted as an initial compensation of the disturbance observer to compensate for the initial friction behavior, and provides the delay-free estimation. The proposed compensation method has been verified by experiments using a prototype of industrial positioning devices.
Industrial Electronics, 2009. IECON '09. 35th Annual Conference of IEEE; 12/2009
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ABSTRACT: We propose a method for detecting precursors, such as small rock and/or soil fall, which occur prior to massive slope failure. The key feature of our method is directly recognizing the trajectory of a small collapse using spatiotemporal Gabor filtering. Simulation analysis, where the conditions of the simulation are quantitatively defined, reveals the effectiveness of the proposed method in detecting a tiny moving object with low contrast in the background under low frame-rate video monitoring. Experiments using actual monitoring videos of a hazardous slope confirmed the effectiveness of our method. The effects of error factors in an outdoor environment, which may inhibit recognition, are also evaluated.
Systems, Man and Cybernetics, 2009. SMC 2009. IEEE International Conference on; 11/2009
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ABSTRACT: In this paper, we describes the simultaneous perturbation particle swarm optimization which is a combination of the particle swarm optimization and the simultaneous perturbation optimization method. The method has global search capability of the particle swarm optimization and local search one of gradient method by the simultaneous perturbation. Some variations of the method are described. Comparison between these methods and the ordinary particle swarm optimization are shown through five test functions and learning problem of neural networks.
Evolutionary Computation, 2009. CEC '09. IEEE Congress on; 06/2009
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ABSTRACT: Recently, immense multimedia information has come to be exchanged on the Internet, where 3DCG, video, image, sound, and text are involved in various circumstances with terminal devices, networks and users different in their competences and performances. This fact may easily lead to 'digital divide' so called unless any special support is given to the weaker. We have already proposed a new concept of 'universal multimedia access' which easily narrows the digital divide by providing appropriate multimedia expressions according to userspsila (mental and physical) abilities, computer facilities and network environments. In this paper, we present a user interface to support the users in accordance with their abilities, computer facilities and network environments.
Complex, Intelligent and Software Intensive Systems, 2009. CISIS '09. International Conference on; 04/2009
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ABSTRACT: Multi-strip resonators are proposed to reduce the resonator size, and improve spurious and loss property. The number and the distance of strips are controlled to balance these properties. Computer simulation and experimental result agreed quite well to verify the simulated results. A two stage BPF is designed and fabricated, indicating the feasibility of the new resonator.
Microwave Conference, 2008. EuMC 2008. 38th European; 12/2008
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ABSTRACT: This paper presents an experimental study on electrical tree propagation from a point electrode in an epoxy block subjected to polarity-reversed repetitive pulses after dc prestress. When the epoxy block at one end of a long coaxial cable is charged by a dc prestress and then directly grounded by closing a switch at the other end of the cable without any resistance, repetitive voltage pulses are applied to the epoxy block with a change in its polarity. In test for polarity-reversed tree with -dc prestress, tree length tends to be shorter than that for an positive impulse tree without prestress. However, the shape of the polarity-reversed tree becomes more busy. In test for polarity reversed tree with +dc prestress, tree length at room temperature is very short for both the pulses with and without the prestress because of the poor propagation capability in negative streamer. However, polarity-reversed tree at 120degC is very large because the negative streamer propagation is followed by the successive positive streamer caused by the second polarity reversal.
Electrical Insulating Materials, 2008. (ISEIM 2008). International Symposium on; 10/2008
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ABSTRACT: After a public experiment of the indoor guidance system using FLC (fluorescent light communication), we found that FLC provides a promising medium for the installation of a guidance system for the visually impaired. However, precise self-positioning was not satisfactorily achieved. In this article, we propose a new self-positioning method, one that uses a combination of RFID (radio-frequency identification), Bluetooth and FLC. We analyzed the situation and developed a model that combined the three communication modes. Then we performed a series of experiments and get some results in the first step.
Engineering in Medicine and Biology Society, 2007. EMBS 2007. 29th Annual International Conference of the IEEE; 09/2007
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ABSTRACT: An optical transceiver module for the dense wavelength-division-multiplexing (DWDM) applications is successfully realized with so-called small form factor pluggable (SFP) platform that is well known as the smallest platform for 2.5.Gbps optical transceiver. The power consumption of DWDM-SFP modules we developed is reduced drastically, and that is 1.0 W maximum at the operating case temperature (Tc) range of -5 to 70 degC (for typical DWDM-SFP samples). This remarkable low power consumption is achieved by next three techniques which are a compact coaxial transmitter optical sub assembly (TOSA) package with a micro thermoelectric cooler (micro-TEC), a transceiver IC chip with many functions integrated therein and an unique structure which the TOSA is isolated from other heat sources.
Electronic Components and Technology Conference, 2005. Proceedings. 55th; 07/2005
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ABSTRACT: We have developed pulse tube cryocoolers for high temperature superconducting (HTS) filter subsystems used in the base stations
of mobile telecommunication systems. In July 1999, we reported on our development of a 5 W Stirling pulse tube cryocooler
with a contact-type compressor,1 with a cooling capacity of 5.5 W at 80 K for 200 W of input power. However, demands for a smaller-sized cryocooler with higher
efficiency and with 5-year reliability prompted us to develop such a cryocooler with a U-type expander and a flexure-bearing-supported
linear compressor with opposed pistons.
We have developed an HTS filter and a long-life Stirling pulse tube cryocooler to cool the filter whose cooling capacity is
around 1W at 80 K, as previously discussed in a progress report.2 For a compressor input power of 60 W at an operating frequency of 52 Hz and a pressure-volume (P-V) work of 26 W, and for
a compressor efficiency of 45%, this cryocooler achieved a cooling capacity of 1.05 W at 80 K (0.63 W at 70 K), a specific
power of 92 W/W, 5.5% Carnot (3.9% Carnot at 70 K), and a specific P-V work of 40 W/W, with a minimum temperature of 57 K
in an ambient of 23°C.
The key devices of this filter subsystem are an HTS filter and a low noise amplifier (LNA). The HTS filter is made from a
YBCO HTS thin film and has a fractional bandwidth below 1.2% at 2 GHz and has a minimum insertion loss at 0.3dB. The HTS filter
and the LNA are operated at a constant temperature of 70 K and the cooling capacity needed by them is 0.6 W. We integrated
them with the cryocooler into a subsystem, and the external dimensions of this system are 194 mm high, 180 mm wide, 250 mm
deep, with a total volume of 8.7 L.
12/2001: pages 119-124;
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ABSTRACT: Summary form only given, as follows. We describe a compact,
long-life High-Temperature Superconducting (HTS) filter subsystem for
mobile telecommunication base stations. This system consists mainly of a
HTS filter and a low-noise amplifier (LNA), which are cooled by a
Stirling pulse tube type cryocooler. The cooler is compact and has a
service life of more than 5 years, theoretically, because its head has
no moving parts. The 13-pole HTS filter, which as a 20 MHz bandwidth at
1.955 GHz, is made using a YBCO HTS thin film, and has a minimum
insertion loss of less than 0.2 dB at 70 K. The HTS filter and LNA are
packaged in a vacuum chamber, which can retain vacuum for more than 5
years operated under constant temperature-controlled conditions
IEEE Transactions on Appiled Superconductivity 04/2001; · 1.04 Impact Factor
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ABSTRACT: To reduce gas desorption, especially dynamic gas desorption, of ultrahigh vacuum materials, it is necessary to reduce carbon on the surface and in the rear surface layer which deteriorates dynamic gas desorption coefficient. To eliminate carbon, an ozone treatment was applied to metal surfaces. The surfaces of aluminum, copper, and stainless steel without any treatment were exposed to 250 ppm ozone using air with flow rates of 1 l/min for 24 or 48 hours. The samples were shown to decrease carbon levels, especially on Cu and Al surfaces, as detected by Auger electron spectroscopy (AES). In addition, no carbon was detected in the rear surface layers as detected by sputter profiling. The detectability of AES is on the order of 10<sup>-2</sup> monolayers or approximately 3×10<sup>13</sup> carbon atoms/cm<sup>2</sup>. The thickness of the oxidized layer was 6.3, 8.1, and 3.0 times the native oxide layer for Cu (120 Å), Al (170 Å), and stainless steel (60 Å), respectively. X‐ray photoelectron spectroscopy shows (1) the ratio (O/Al) is 1.5 for the treated and 1.4 for the nontreated samples; (2) 24 at. % of Cu<sup>2+</sup> is included in the treated but 78 at. % of Cu and Cu<sup>+ </sup>for the nontreated samples; (3) the oxide component excluding hydroxide is 29 at. % for the treated and 3 at. % for nontreated samples. The treated surfaces show low carbon adsorption characteristics: little carbon was detected by AES on copper and aluminum treated surfaces stored in a covered glass dish for more than four days and on an ozonized copper surface stored in aluminum foil for more than 100 days. © 1995 American Vacuum Society
Journal of Vacuum Science & Technology A Vacuum Surfaces and Films 06/1995; · 1.25 Impact Factor
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ABSTRACT: Features of the electrostatic energy analyzer of a cylindrical type are described with the aim of measuring the end‐loss ions in the tandem mirror GAMMA 10. The analyzer provides us with information about ion density distributions in a loss‐cone region of velocity space as well as plug potential in the tandem mirror. Application of the analyzer to the tandem mirror experiments and the energy spectrum analysis are discussed.
Review of Scientific Instruments 05/1991; · 1.37 Impact Factor
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ABSTRACT: Differential Hall‐effect and sheet‐resistivity measurements have been carried out to investigate electrical properties of p‐type layers formed by implanting 100‐keV Zn ions into Cr‐doped semi‐insulating GaAs at room temperature and by subsequent laser irradiation (Nd : YAG, λ=1.06 μm) using chemical‐vapor‐deposited (CVD) Si 3 N 4 films as the encapsulant. It has been shown that very shallow (approximately 0.3 μm) and highly doped (p max =4×10<sup>19</sup> cm<sup>-3</sup>) p‐type GaAs layers can be fabricated by Zn implantation with an ion dose of 1.0×10<sup>15</sup> cm<sup>-2</sup> followed by laser irradiation at a beam energy density of 1.5 J cm<sup>-2</sup>.
Journal of Applied Physics 10/1979; · 2.17 Impact Factor
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