Showing papers by "Mitsubishi Electric published in 2005"

Localization via ultra-wideband radios: a look at positioning aspects for future sensor networks

Abstract: UWB technology provides an excellent means for wireless positioning due to its high resolution capability in the time domain. Its ability to resolve multipath components makes it possible to obtain accurate location estimates without the need for complex estimation algorithms. In this article, theoretical limits for TOA estimation and TOA-based location estimation for UWB systems have been considered. Due to the complexity of the optimal schemes, suboptimal but practical alternatives have been emphasized. Performance limits for hybrid TOA/SS and TDOA/SS schemes have also been considered. Although the fundamental mechanisms for localization, including AOA-, TOA-, TDOA-, and SS-based methods, apply to all radio air interface, some positioning techniques are favored by UWB-based systems using ultrawide bandwidths.

Variable-phase-shift-based RF-baseband codesign for MIMO antenna selection

Abstract: We introduce a novel soft antenna selection approach for multiple antenna systems through a joint design of both RF (radio frequency) and baseband signal processing. When only a limited number of frequency converters are available, conventional antenna selection schemes show severe performance degradation in most fading channels. To alleviate those degradations, we propose to adopt a transformation of the signals in the RF domain that requires only simple, variable phase shifters and combiners to reduce the number of RF chains. The constrained optimum design of these shifters, adapting to the channel state, is given in analytical form, which requires no search or iterations. The resulting system shows a significant performance advantage for both correlated and uncorrelated channels. The technique works for both transmitter and receiver design, which leads to the joint transceiver antenna selection. When only a single information stream is transmitted through the channel, the new design can achieve the same SNR gain as the full-complexity system while requiring, at most, two RF chains. With multiple information streams transmitted, it is demonstrated by computer experiments that the capacity performance is close to optimum.

Novel CO2 Absorbents Using Lithium-Containing Oxide

Abstract: We have discovered a series of lithium-containing oxides that immediately react with ambient carbon dioxide (CO2) up to 700°C. The products react and return reversibly to the oxides at a temperatures higher than about 700°C. The absorption capacity surpasses that of other CO2 absorbents by a factor of 10. Utilizing these absorbents, the possibility of a CO2 separation system that operates at around 500°C is proposed. It is generally believed that a CO2 separation process operable at temperatures higher than 500°C has the special benefit of a small energy penalty. Moreover, the absorption also proceeds at ambient temperature in the atmospheric environment. This property offers the possibility of many other applications, such as air cleaners or cartridges. Therefore, we think these materials have the potential to make a valuable contribution to the realization of CO2 emission control.

A highlight scene detection and video summarization system using audio feature for a personal video recorder

Abstract: The personal video recorder such as recordable-DVD recorder, Blu-ray disc recorder and/or hard disc recorder has become popular for a large volume storage device for video/audio content data and a browsing function that would quickly provide a desired scene to the user is required as an essential part of such a large capacity recording/playback system. We propose a highlight scene detection function by using only 'audio' features and realize a browsing function for the recorder that enables completely automatic detection of sports highlights. We detect sports highlights by identifying portions with "commentator's excited speech" using Gaussian mixture models (GMM's) trained using the MDL criterion. Our computation is carried out directly on the MDCT coefficients from the AC-3 coefficients thus giving us a tremendous speed advantage. Our accuracy of detection of sports highlights is high across a variety of sports.

An Experimental Optical Three-axis Tactile Sensor for Micro-Robots

Abstract: This paper describes a micro-optical three-axis tactile sensor capable of sensing not only normal force, but also shearing force. The normal force was detected from the integrated gray-scale values of bright pixels emitted from the contact area of conical feelers. The conical feelers were formed on a rubber sheet surface that maintains contact with an optical waveguide plate. The shearing force was detected from horizontal displacement of the conical feeler. In the experiments, a precise multi-axial loading machine was developed to measure sensing characteristics of the present sensor. Results show that the normal force was specified uniquely under combined force conditions and that the shearing force was specified by modifying the relationship between the shearing force and the horizontal displacement on the basis of normal force. We formulated a set of expressions to derive the normal force and the shearing force by taking into account this modification. Furthermore, calibration coefficients were identified for transforming the integration of gray-scale values into the normal force and for transforming the horizontal displacement into the shearing force. This result suggests that the expressions can estimate the normal force and the shearing force in wide-load regions.

Refrigeration/air conditioning equipment

Abstract: Refrigeration/air conditioning equipment includes a first internal heat exchanger for exchanging heat between a refrigerant to be sucked in a compressor and a high-pressure liquid refrigerant, an injection circuit for evaporating a bypassed high-pressure liquid at intermediate pressure and injecting the vaporized refrigerant into the compressor, a second internal heat exchanger for exchanging heat between the high-pressure liquid refrigerant and the refrigerant to be injected, and a heat source for heating the refrigerant to be injected.

Pulse pre-pump method for cm-order spatial resolution of BOTDA

Abstract: The distributed Brillouin scattering technique, using pulse width of 1ns, that is, one order of magnitude smaller than currently available in commercial applications of BOTDA, was successfully implemented and examined in laboratory environment by Bao et al. However, the two main problems prohibits its commercial use, namely, the measurement setting must be modified each time the measurements object is changed, and, furthermore, long-range measurements cannot be effectively carried out due to substantial increase in signal noise level with the measurement distance. This paper presents a new technique, which overcomes both of these problems, by introducing the pre-pump pulse in front of standard laser pulse. Theoretical analysis clearly demonstrates that the cm-order distributed sensing, independent of the fiber length, can be realized. Moreover, a quantitative analysis of strain measurement accuracy is also presented.

Highlights extraction from sports video based on an audio-visual marker detection framework

Abstract: We propose to use a visual object (e.g., the baseball catcher) detection algorithm to find local, semantic objects in video frames in addition to an audio classification algorithm to find semantic audio objects in the audio track for sports highlights extraction. The highlight candidates are then further grouped into finer-resolution highlight segments, using color or motion information. During the grouping phase, many of the false alarms can be correctly identified and eliminated. Our experimental results with baseball, soccer and golf video are promising.

Sub-hundred nanometre pitch measurements using an AFM with differential laser interferometers for designing usable lateral scales

Abstract: We have developed a new atomic force microscope with differential laser interferometers (DLI-AFM), carried out test measurements of the prototype 1D-grating standards with pitches of 100, 80, 60 and 50 nm using the DLI-AFM and evaluated the uncertainty in the pitch measurements. In the procedures of the pitch calculation, two types of definitions of the peak positions, 'the centre of gravity method', and 'the zero-crossing method', were compared. The zero-crossing method was adopted in this study since the standard deviation of pitches by the zero-crossing method was smaller than that by the centre of gravity method. The expanded uncertainty (k = 2) was approximately 0.20 nm and was only 0.4% for the nominal pitch of 50 nm. We propose a design of usable 1D-grating standards as certified reference materials.

DPA leakage models for CMOS logic circuits

Abstract: In this paper, we propose new models for directly evaluating DPA leakage from logic information in CMOS circuits. These models are based on the transition probability for each gate, and are naturally applicable to various actual devices for simulating power analysis. We also report the effectiveness of the previously known enhanced DPA on our model. Furthermore, we demonstrate the weakness of previously known hardware countermeasures for both our model and FPGA and suggest secure conditions for the hardware countermeasure.

Method for stabilizing and precisely locating pointers generated by handheld direct pointing devices

Abstract: The invention provides a method to stabilize a pointer displayed within an output image. The method enables the user to magnify selected areas within the output image. This allows the user to ‘zoom’ in on areas of interest in the output image, and to make accurate selections with the stabilized pointer. Design features of the method enable pixel and sub-pixel accurate pointing, which is not possible with most conventional direct pointing devices. The invention can be worked for 2D and 3D pointers.

Transmission control method, mobile station, and communication system

Abstract: Conventionally, there is a problem that a state transition of E-TFC changes according to QoS for descriptions of data to be transmitted, and therefore a mobile station's operation is not decided uniquely. To solve this problem, a transmission control method in accordance with the present invention includes a step of selecting transmission control information according to a combination of user data transmitted, via a transport channel, from an upper layer, and a step of transmitting the transmission control information, as well as a physical channel into which two or more transport channels are multiplexed, to a fixed station, the transmission control information including at least transmit power information.

Communication quality judgment method, mobile station, base station, and communications system

Abstract: In order to carry out high-speed packet communications using a large-volume transmission channel like an E-DCH, uplink communication quality must be good. However, in a state in which a link imbalance occurs, a mobile station cannot estimate the uplink communication quality from downlink communication quality. Therefore, the mobile station calculates a path loss from the setting power of a common pilot channel which is notified from a base station, and the received power of the common pilot channel received thereby, and also estimates the received power in the base station on the basis of this path loss. The mobile station further judges the uplink communication quality by estimating the SIR in the base station by using the interference power notified from the base station and the estimated received power.

Characteristics of 4H–SiC MOS interface annealed in N2O

Abstract: 4H–SiC(0 0 0 1) MOSFET annealed in N2O at below 1150 °C is systematically investigated. Inversion-type planar MOSFETs show higher channel mobility and lower threshold voltage by increasing anneal temperature. Through C–V measurement of n-type MOS capacitors, the interface state density is revealed to decrease at higher anneal temperature. The field effect mobility of 30 cm2/Vs is achieved by 1150 °C anneal for 3 h, which is about 10 times higher than that of not annealed MOSFET. Epitaxial n-channel MOSFET annealed in N2O has been also fabricated. A positive threshold voltage of 0.46 V and the field effect mobility of 45 cm2/Vs are attained. The effective mobility at 2.5 MV/cm is 34 cm2/Vs, which is five times higher than that for not annealed sample, suggesting that the N2O anneal improves the MOS interface quality.

Image display apparatus

Abstract: An image display apparatus is provided that enables the chromaticity of a display screen of a display apparatus to be adjusted to the chromaticity desired by a user. The image display apparatus is formed by a backlight unit that is provided with a plurality of light sources and by an image display panel that is placed at a front surface of the backlight unit. The image display apparatus performs a monochrome display. In the image display apparatus, the light sources have at least three different types of luminescent colors that surround a target color on a chromaticity diagram.

A key pre-distribution scheme for secure sensor networks using probability density function of node deployment

Abstract: Pairwise key establishment is a fundamental service provided in secure sensor networks. However, due to resource constraints, establishing pairwise keys is not a trivial task. Recently, a random key pre-distribution scheme and its improvements have been proposed. The scheme proposed by Du et al. uses deployment knowledge to improve the performance and security of sensor networks. However, this scheme assumes group-based deployment in which groups of nodes are deployed from horizontal grid points. This assumption limits applications of the scheme. Therefore, in this paper, we propose an advanced key pre-distribution scheme in which different keys are logically mapped to two-dimensional positions, and the keys that are distributed to a node are determined by positions estimated using a node probability density function. The scheme can be applied to any deployment model provided the node probability density function has already been determined. Furthermore, simulation results show that our scheme achieves higher connectivity than Du et al.'s scheme.

QueryLines: approximate query for visual browsing

Abstract: We introduce approximate query techniques for searching and analyzing two-dimensional data sets such as line or scatter plots. Our techniques allow users to explore a dataset by defining QueryLines: soft constraints and preferences for selecting and sorting a subset of the data. By using both preferences and soft constraints for query composition, we allow greater flexibility and expressiveness than previous visual query systems. When the user over-constrains a query, for example, a system using approximate techniques can display "near misses" to enable users to quickly and continuously refine queries.

Design and Development of SIS Mixers for ALMA Band 10

Abstract: In this paper, we report on the design and experimental results of a fix-tuned Superconductor-Insulator-Superconductor (SIS) mixer for Atacama Large Millimeter/submillimeter Array (ALMA) band 8 (385-500 GHz) receivers. Nb-based SIS junctions of a current density of 10 kA/cm/sup 2/ and one micrometer size (fabricated with a two-step lift-off process) are employed to accomplish the ALMA receiver specification, which requires wide frequency coverage as well as low noise temperature. Parallel-connected twin junctions (PCTJ) are designed to resonate at the band center to tune out the junction geometric capacitance. A waveguide-microstrip probe is optimized to have nearly frequency-independent impedance at the probe's feed point, thereby making it much easier to match the low-impedance PCTJ over a wide frequency band. In addition, a superconducting magnet fixed onto the compact mixer block to provide efficient magnetic field coupling is designed. The SIS mixer demonstrates a minimum double-sideband receiver noise temperature of 108 K at the band center and temperatures of less than 167 K over the whole band (for an intermediate-frequency range of 4-8 GHz).

Image processing apparatus, image processing method, and image display apparatus

Abstract: The frame-parallax-adjustment-amount generating unit outputs, as first parallax data, parallax data of an image portion protruded most among image portions protruded more than a first reference value from a pair of frame images forming a three-dimensional image. The pixel-parallax-adjustment-amount generating unit outputs, as second parallax data, parallax data of an image portion retracted more than a second reference value from the pair of frame images. The adjusted-image generating unit generates a pair of image output data by moving the entire pair of image input data to the inner side based on the first parallax data and moving an image portion retracted more than the second reference value of the pair of image input data based on the second parallax data to adjust a parallax amount and outputs the pair of image output data.

Bandwidth expansion of narrowband speech using non-negative matrix factorization

Abstract: In this paper, we present a novel technique for the estimation of the high frequency components (4-8kHz) of speech signals from narrow-band (0-4 kHz) signals using convolutive Non-Negative Matrix Factorisation (NMF). The proposed technique utilizes a brief recording of simultaneous broad band and narrow band signals from a target speaker to learn a set of broad-band non-negative bases for the speaker. The low-frequency components of these bases are used to determine how the high-frequency components must be combined in order to reconstruct the high-frequency components of new narrow-band signals from the speaker. Experiments reveal that the technique is able to reconstruct broadband sppech that is perceptually virtually indistinguishable from true broadband recordings. Eurospeech 2005

System for controlled operation of elevator in case of fire and method of controlled operation of elevator in case of fire

Abstract: A fire emergency control operation system for an elevator includes: evacuation time calculating means for acquiring a positional relationship between the elevator and the fire sensor which performs the fire detecting operation based upon information from the fire sensor to calculate an evacuation operation time based upon the obtained positional relationship; fire occurrence floor specifying means for specifying a fire occurrence floor based upon the information from the fire sensor; remaining person count input means for inputting a number of the remaining persons in correspondence with each of the floors; schedule deciding means for deciding an evacuation operation schedule for the respective floors when the remaining persons are conveyed to the evacuation floor based upon the information from the evacuation time calculating means, the fire occurrence floor specifying means, and the remaining person count input means; display means for displaying thereon a content of the evacuation operation schedule; and elevator control means for controlling the operation of the elevator based upon the information of the evacuation operation schedule.

Contents Distribution System

Abstract: When the DRM mode indicated by a client terminal 1 differs from DRM (Digital Rights Management) modes available to a license server 2 and a distribution server 4 , the license server 2 requests a DRM mode converting server 6 to convert the DRM mode of the multimedia contents. When the DRM mode converting server 6 receives the conversion request of the DRM mode, it converts the DRM mode of the multimedia contents distributed from the distribution server 4 to the DRM mode available to the client terminal 1 , and transfers the multimedia contents passing through the conversion to the client terminal 1.

Cogging-force-reduction techniques for linear permanent-magnet machines

Abstract: The paper describes two techniques for reducing the cogging force associated with the finite length of the ferromagnetic armature core of a tubular permanent-magnet machine. Analytical expressions for predicting the cogging force which is associated with armature cores having skewed or stepped end faces are established, and a cogging-force-minimisation technique is employed to determine an optimal armature-core length. The validity of the analytical cogging-force predictions and the effectiveness of the cogging-force-reduction techniques are verified by three-dimensional finite-element analyses and experimental measurements.

Research & development of superconducting fault current limiter in Japan

Abstract: R&D of fundamental technologies for superconducting AC Power equipment (Super-ACE project) started as a national project, for a five-year plan since fiscal 2000 by MITI and NEDO. This project is to research and develop the basic technology of super-conductive cable, fault current limiter and transformer. This paper summarizes the research and development of following 2 types FCL. The R&D of the SN transition resistive type superconducting thin film fault current limiter aims to establish large-current/high-voltage technology by arranging films in multi-parallel/series, and increasing the current-carrying capacity through widening the area of the thin film of the current limiting element. The R&D of the reactor for a rectifier-type fault current limiter using coils of superconducting wire of the Ag sheath Bi2223 tape, aiming to apply it to high-voltage systems.

Method for Selecting Antennas and Beams in MIMO Wireless LANs

Abstract: A computer implemented method selects antennas in a multiple-input, multiple-output wireless local area network that includes multiple stations, and each station includes a set of antennas. Multiple consecutively transmitted sounding packets are received in a station. Each sounding packet corresponds to a different subset of the set of antennas. A channel matrix is estimated from the multiple consecutively transmitted sounding packets. A frame including a high throughput (HT) control field is sent to initiate a selecting of antennas, and a subset of antennas is selected according to the channel matrix.

Cellular telephone with ear proximity display and lighting control

Abstract: A cell phone includes illuminated components and a proximity sensor. The proximity sensor detects when the cell phone is coupled to the ear of a user. Therefore, the proximity detector is placed, in part, near the loudspeaker of the cell phone. The proximity sensor controls the illumination of the illuminated components according to the coupling. The illumination is off when coupled, an on when not coupled. The amount of illumination can depend to the intensity of ambient light as measured by a photodiode.

Mobile station, fixed station, communication system and communication method

Abstract: There is a problem that no unique specific detailed regulation is existent with respect to mobile station status information to be notified by mobile stations to a fixed station, so that the operations of the mobile stations within a communication system may be different from one another and hence no efficient scheduling (wireless resource assignment) of the uplink can be achieved. A communication method includes a transmission process in which to multiplex a transport channel, on which data is transferred from an upper order layer, with a physical data channel and transmit the multiplexed channel to a fixed station; a status notification process in which to notify status information including information related to a transmission power margin to be used for a scheduling; and a transmission control process in which to receive a result of the scheduling to control the transmission process. In the status information notification process, indexes added to respective predetermined transmission power margin levels as divided between the upper and lower limits of the transmission power margin are notified of as the status information.