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[Keyword] SEM(686hit)

621-640hit(686hit)

  • Hierarchy-Based Networked Organization, Modeling, and Prototyping of Semantic, Statistic, and Numeric Image Information

    Hussain Sabri SHAKIR  Makoto NAGAO  

     
    PAPER-Databases

      Vol:
    E78-D No:8
      Page(s):
    1003-1020

    This paper presents a comprehensive framework for the organization, retrieval, and adaptation of image information and meta-information in image database systems. The multi-level hierarchy of images that emphasizes the composition of visual entities (such as Human, Chair, , etc.) from its constituents (eye, leg, , etc.) is managed by a host architecture that is called the semantic tree. This architecture is shown to integrate description, numeric, and statistic image constituent's information into a compound space that is used as retrieval basis for semantic, sketch, and template image queries and several other composite query types. The core architecture based on which the semantic tree is constructed is shown to offer several new features such as simple prototyping, complex prototyping, low storage requirements, and automatic knowledge acquisition compatibility. The object oriented data model constitutes our comparison basis throughout the paper. Methods (functions) used to access image information are shown to be organized into a separate architecture called the query dictionary. This architecture is shown to offer a convenient hierarchical message passing medium using which a variety of composite queries are constructed. Interaction between semantic trees and the query dictionary is clarified through several examples. It is shown that the semantic tree architecture embraces additional networking semantic intormation through a range of relation representation models, the first of which is introduced in this paper. A new inheritance method called semantic relation spreading is introduced. Comprehensive examples are given to demonstrate the versatility of the new strategy.

  • High Fmax AlGaAs/GaAs HBTs with Pt/Ti/Pt/Au Base Contacts for DC to 40 GHz Broadband Amplifiers

    Tohru SUGIYAMA  Yasuhiko KURIYAMA  Norio IIZUKA  Kunio TSUDA  Kouhei MORIZUKA  Masao OBARA  

     
    PAPER

      Vol:
    E78-C No:8
      Page(s):
    944-948

    A low contact resistivity of 4.410-7 Ωcm2 for AlGaAs/GaAs HBTs was realized using Pt/Ti/Pt/Au base metal and a 81019 cm-3 highly-doped base. A high fmax of 170 GHz was achieved by reducing a base resistance. The formation of oxide-free interface between an AlGaAs graded base and Pt-based metal was demonstrated with Auger electron spectroscopy. The optimization of the growth condition conquered the rapid current-induced degradation in the highly Be-doped HBTs. An extremely wide bandwidth of 40 GHz was attained by a Darlington feeback amplifier fabricated using these high-fmax HBTs. These properties indicate that the application of AlGaAs/GaAs HBTs can be expected to extend to future ultrahigh-speed optical transmission systems.

  • Cooperative Spoken Dialogue Model Using Bayesian Network and Event Hierarchy

    Masahiro ARAKI  Shuji DOSHITA  

     
    PAPER

      Vol:
    E78-D No:6
      Page(s):
    629-635

    In this paper, we propose a dialogue model that reflects two important aspects of spoken dialogue system: to be robust' and to be cooperative'. For this purpose, our model has two main inference spaces: Conversational Space (CS) and Problem Solving Space (PSS). CS is a kind of dynamic Bayesian network that represents a meaning of utterance and general dialogue rule. Robust' aspect is treated in CS. PSS is a network so called Event Hierarchy that represents the structure of task domain problems. Cooperative' aspect is mainly treated in PSS. In constructing CS and making inference on PSS, system's process, from meaning understanding through response generation, is modeled by dividing into five steps. These steps are (1) meaning understanding, (2) intention understanding, (3) communicative effect, (4) reaction generation, and (5) response generation. Meaning understanding step constructs CS and response generation step composes a surface expression of system's response from the part of CS. Intention understanding step makes correspondence utterance type in CS with action in PSS. Reaction generation step selects a cooperative reaction in PSS and expands a reaction to utterance type of CS. The status of problem solving and declared user's preference are recorded in mental state by communicative effect step. Then from our point of view, cooperative problem solving dialogue is regarded as a process of constructing CS and achieving goal in PSS through these five steps.

  • An Analysis of Traceability in Requirements Documents

    Kenji TAKAHASHI  Shuichiro YAMAMOTO  

     
    PAPER-Software Systems

      Vol:
    E78-D No:4
      Page(s):
    394-402

    We study the correspondence between problem descriptions and requirements specification documents derived from them. Based on the results of this investigation, a model that integrates the problem space and the requirements specification space is developed. This integration is based on a semantic network representation. We also propose a model of the requirements elicitation process that is consistent with our empirical studies of traceability in requirements documents. In this process, analysts derived requirements specifications from incomplete and ambiguous problem descriptions given by customers, identify missing information, completed it, and then decide the system boundaries that define which part of the problem descriptions to implement as the target system. The model can be used to complete problem descriptions given by customers and determine the system boundaries.

  • A Shortest Path Algorithm for Banded Matrices by a Mesh Connection without Processor Penalty

    Aohan MEI  Yoshihide IGARASHI  

     
    PAPER-Algorithms, Data Structures and Computational Complexity

      Vol:
    E78-A No:3
      Page(s):
    389-394

    We give an efficient shortest path algorithm on a mesh-connected processor array for nn banded matrices with bandwidth b. We use a b/2b/2 semisystolic processor array. The input data is supplied to the processor array from the host computer. The output from the processor array can be also supplied to itself through the host computer. This algorithm computes all pair shortest distances within the band in 7n4b/21 steps.

  • Vertical Cavity Surface-Emitting Laser Array for 1.3 µm Range Parallel Optical Fiber Transmissions

    Toshihiko BABA  Yukiaki YOGO  Katsumasa SUZUKI  Tomonobu KONDO  Fumio KOYAMA  Kenichi IGA  

     
    LETTER-Opto-Electronics

      Vol:
    E78-C No:2
      Page(s):
    201-203

    Long-wavelength 1.3 µm GaInAsP/InP vertical cavity surface-emitting lasers (VCSELs) have been demonstrated in an array configuration. With the strong current confinement by a buried heterostructure and the efficient optical feedback by a dielectric cavity, five VCSEL elements in a 24 array operated at room temperature with 5 mW total power output and wavelength error within 5%. The stacked planar optics including the VCSEL array is a promising optical transmitter in ultra large scale parallel optical communication systems.

  • High-Speed Modulation with Low-Threshold 1.3µm-Wavelength MQW Laser Diodes

    Kazuhiro TANAKA  Kaoru NAKAJIMA  Tetsufumi ODAGAWA  Hiroyuki NOBUHARA  Kiyohide WAKAO  

     
    LETTER

      Vol:
    E78-C No:1
      Page(s):
    91-93

    Laser diodes for optical interconnections are ideally high speed, work over a wide temperature range, and are simple to bias. This paper reports high bit-rate modulation with nearly zero bias with very low threshold 1.3µm-wavelength laser diodes over a wide temperature range. At the high temperature of 80, lasing delay was 165 ps with nearly zero bias. We demonstrated 2.5 Gbit/s modulation over a wide temperature range. Eye opening was over 34% of one time slot.

  • Assembly Plan Generation from an Assembly Illustration by Integrating the Information from Explanatory Words

    Shoujie HE  Norihiro ABE  Tadahiro KITAHASHI  

     
    PAPER-Foundations of Artificial Intelligence and Knowledge Processing

      Vol:
    E77-A No:9
      Page(s):
    1546-1559

    This paper presents an approach for assembly plan generation from an assembly illustration. Previously, we have already proposed an approach for the assembly plan related information acquisition from an assembly illustration, in which auxiliary lines were taken as clues. However, some ambiguity remains in dynamic information such as assembly operations and their execution order. We have verified through experiments that the ambiguity could be made clear by referring to the feedback information from the completed assemblage after the assembly operations shown in the current illustration. But in fact, in an assembly illustration there are not only the figures of mechanical parts and the auxiliary lines for visualizing their assembly relations, but explanatory words and explanatory lines as well. Explanatory words can basically be classified into two categories: instructions on assembly operations and mechanical part names. The former explicitly describes dynamic information such as the details of assembly operations. The latter also implies dynamic information such as the function of a mechanical part. Explanatory lines are usually drawn for making clear the explanatory relations. Naturally we consider that to integrate the information from explanatory words with that already obtained through the extraction of auxiliary lines will probably enable us to generate an unambiguous assembly plan from the currently observing illustration.

  • A 3 Volt 1 Mbit Full-Featured EEPROM Using a Highly-Reliable MONOS Device Technology

    Shin-ichi MINAMI  Kazuaki UJIIE  Masaaki TERASAWA  Kazuhiro KOMORI  Kazunori FURUSAWA  Yoshiaki KAMIGAKI  

     
    PAPER-Non-volatile Memory

      Vol:
    E77-C No:8
      Page(s):
    1260-1269

    A low-voltage operation and highly-reliable nonvoltatile semiconductor memory with a large capacity has been manufactured using 0.8-µm CMOS technology. This 3-volt, 1-Mbit, full-featured MONOS EEPROM has a chip size of 51.3 mm2 and a memory cell size of 23.1µm2. An asymmetric programming voltage method fully exploits the abilities of the MONOS device and provides 10-year data retention after 106 erase/write cycles. Because of its wide-margin circuit design, this EEPROM can also be operated at 5 volts. High-speed read out is provided by using the polycide word line and the differential sense amplifier with a MONOS dummy memory. New functions such as data protection with software and programming-end indication with a toggle bit are added, and chips are TSOP packaged for use in many kinds of portable equipment.

  • CMOS Embedded RAMs for Digital Communication Systems

    Masao MIZUKAMI  Yoichi SATOH  Takahiko KOZAKI  Yasuo MIKAMI  

     
    PAPER-General Technology

      Vol:
    E77-C No:8
      Page(s):
    1361-1368

    This paper describes CMOS embedded RAMs we developed utilizing 1.3 µm and 0.8 µm process technologies. Our goal was to achieve high-performance switching for digital communication systems. Because such switching can best be obtained by using high-performance embedded RAMs, we used 0.8 µm process technology and developed a 4 kW9 b single-port embedded RAM with 5 ns access time and 100 mW power dissipation during32 MHz operation, and a 1 kW9 b dual-port embedded RAM with 3.7 ns access time and 100 mW power dissipation during 40 MHz operation. We implemented these RAMs on one chip in developing three time-switch VLSIs, one buffer memory VLSI for ATM switches, and two cross-connect switch VLSIs.

  • Highly Reliable Flash Memories Fabricated by in-situ Multiple Rapid Thermal Processing

    Takahisa HAYASHI  Yoshiyuki KAWAZU  Akira UCHIYAMA  Hisashi FUKUDA  

     
    PAPER-Non-volatile Memory

      Vol:
    E77-C No:8
      Page(s):
    1270-1278

    We propose, for the first time, highly reliable flash-type EEPROM cell fabrication using in-situ multiple rapid thermal processing (RTP) technology. In this study, rapid thermal oxynitridation tunnel oxide (RTONO) film formations followed by in-situ arsenic (As)-doped floating-gate polysilicon growth by rapid thermal chemical vapor deposition (RTCVD) technologies are fully utilized. The results show that after 5104 program/erase (P/E) endurance cycles, the conventional cell shows 65% narrowing of the threshold voltage (Vt) window, whereas the RTONO cell indicates narrowing of less than 20%. A large number of nitrogen atoms (1020 atoms/cm3) are confirmed by secondary ion mass spectrometry (SIMS), pile up at the SiO2/Si interface and distribute into bulk SiO2. It is considered that in the RTONO film stable Si-N bonds are formed which minimize electron trap generation as well as the neutral defect density, resulting in lower Vt shifts in P/E stress. In addition, the RTONO film reduces the number of hydrogen atoms because of final N2O oxynitridation. The SIMS data shows that by the in-situ RTCVD process As atoms (91020 atoms/cm3) are incorporated uniformly into 1000--thick film. Moreover, the RTCVD polysilicon film indicates an extremely flat surface. The time-dependent dielectric breakdown (TDDB) characteristics of interpoly oxide-nitride-oxide (ONO) film exhibited no defect-related breakdown and 5 times longer breakdown time as compared to phosphorus-doped polysilicon film. Therefore, the flash-EEPROM cell fabricated has good charge storing capability.

  • Optimization of Queries with ADT Functions

    Xiaodong ZHANG  Nobuo OHBO  

     
    PAPER-Databases

      Vol:
    E77-D No:6
      Page(s):
    660-668

    ADTs (Abstract Data Types) have been known as a promising feature for extending the database applications to CAD/CAM and other engineering areas. This extension has brought a new dimension to query optimization. Conventional query optimization methods, which considers only joins as the dominant cost factor, are based on the belief that the executions of selections and projections basically take no time. However, in databases that support ADTs, this may not be true since the execution of a selection involving ADT functions may be very time-cosuming. Thus selections with ADT functions should not be considered as inexpensive operations in queries, and the conventional optimization heuristics should be enhanced to correspond to the appearance of the queries of this kind. In this paper, we show the possibility that semijoins can be used as an effective means to reduce the number of evaluations of an ADT function and consequently optimize queries containing expensive ADT selections. We suggest the enhancement of an conventional optimization heuristics by adding a semijoins pre-stage which is an additional component corresponding to expensive ADT selections. By this way, the applicable range of the conventional heuristics are extended to hold the ability of handling queries with ADT functions. Several optimization algorithms are given and some simulation results show the effectiveness of our methods.

  • Study on Semicylindrical Microstrip Applicator for Microwave Hyperthermia

    Takashi SHIMOTORI  Yoshio NIKAWA  Shinsaku MORI  

     
    PAPER

      Vol:
    E77-C No:6
      Page(s):
    942-948

    A semicylindrical microstrip applicator system is proposed and designed, both for microwave heating and for noninvasive temperature estimation, in application to hyperthermia treatment. The experimental results showed that the system functions both as a heating device and as a means of noninvasive temperature estimation. Therefore, electrical switching of these two functions makes the system realize both heating and temperature estimation. These functions reduce the pain of hyperthermia therapy for patients. The system is constructed of a water-loaded cylindrical applicator. Thus, the whole system can be made compact compared to conventional applicators. This improvement allows for various merits, such as realizing a surface cooling effect and decreased leakage of electromagnetic (EM) waves. When the applicator is set as an array arrangement, the system can be used as a microwave heating device. The penetration depth can be varied by adjusting phases of the EM wave radiated from each applicator. The experimental results at 430 MHz showed that semicylindrical microstrip applicators can be expected to be valid for tumor heating at depths within 55 mm. Moreover, by measuring transmission power between the two applicators, the system can be used to estimate temperature inside the medium. The transmission power which was measured in the frequency domain was converted in the time domain. By such a method, temperature distribution was calculated by solving simple simultaneous primary equations. The results of the temperature estimation show that the number of estimated temperature segments which have an error within 0.5 is 28 out of 36. The system can be easily used as a temperature measuring applicator as well as a heating applicator.

  • Control of Electronic State in Organic Semiconductor by Substituent Groups

    Kazuhiro SAITO  Hiroshi YOKOYAMA  

     
    PAPER

      Vol:
    E77-C No:5
      Page(s):
    654-656

    Control of electronic states of dye molecules (organic semiconductors) by introducing appropriate substituent groups has been examined. NH2 (electron-releasing group) and NO2 (electron-withdrawing group) were introduced in thiacarbocyanine dye to modify the electronic states of the dyes. The effect of modification was examined based on the properties of photoelectric cells made by the dye derivatives. Clear increase in photocurrent, more than ten times, was observed when modified dyes were used instead of the original dye. The result shows that the introduction of substituent groups for organic semiconductors is quite effective to control the electronic states, and the introduction can be regarded as doping in molecular level.

  • Defect Detection of Passivation Layer by a Bias-Free Cu Decoration Method

    Tetsuaki WADA  Shinji NAKANO  

     
    PAPER

      Vol:
    E77-C No:4
      Page(s):
    585-589

    New detection method of passivation defect was studied. The method was the Cu decoration method without bias (bias-free Cu decoration). As the result of comparison with conventional method, it was found that a bias-free Cu decoration method was effective, sensitive and simple. In this method, the difference of humidity resistance induced by poor passivation coverage could be evaluated.

  • Measuring AC Emitter and Base Series Resistances in Bipolar Transistors

    Youichiro NIITSU  

     
    PAPER-Integrated Electronics

      Vol:
    E77-C No:4
      Page(s):
    608-614

    A convenient method for determining emitter and base resistances from small signal measurements has been developed. This method is based on Neugroschel's method, but the frequency has been varied instead of varying β0. It is demonstrated that the base resistance was successfully extracted. The extracted emitter resistance depended on the collector current because of the difference between the exact gm value and the approximated one, IC/VT. It has also been shown that the proposed method is more robust than the conventional impedance-circle method even when cross-talk occurs.

  • Taper-Shape Dependence of Tapered-Waveguide Traveling Wave Semiconductor Laser Amplifier (TTW-SLA)

    Syamsul EL YUMIN  Kazuhiro KOMORI  Shigehisa ARAI  Giampaolo BENDELLI  

     
    PAPER-Opto-Electronics

      Vol:
    E77-C No:4
      Page(s):
    624-632

    Operation characteristics of tapered-waveguide traveling wave semiconductor laser amplifier (TTW-SLA) are calculated in terms of quasi adiabatic single mode propagation, signal gain and saturation output power, device efficiency(the efficiency of conversion between the electrical and amplified optical power), and amplified spontaneous emission (ASE) power, and their dependences on the shape of the taper are compared for linear, quadratic, Gaussian and exponential functions, It was found that in the allowed quasi adiabatic single mode propagation condition, linear and Gaussian TTW-SLA have higher saturation output power property, while the exponential TTW-SLA has higher device efficiency property and lower ASE noise of about 0.1 times that of a broad type TW-SLA.

  • A Proposal of New Multiple-Valued Mask-ROM Design

    Yasushi KUBOTA  Shinji TOYOYAMA  Yoji KANIE  Shuhei TSUCHIMOTO  

     
    PAPER-Integrated Electronics

      Vol:
    E77-C No:4
      Page(s):
    601-607

    A new multiple-valued mask-ROM cell and a technique suitable for data detection are proposed. The information is programmed in each of the memory cells as both the threshold voltage and the channel length of the memory cell transistor, and the stored data are detected by selecting the bias condition of both the word-line and the data-line. The datum stored in the channel length is read-out using punch-through effect at the high drain voltage. The feasibility of this mask-ROM's is studied with device simulation and circuit simulation. With this design, it would be possible to get the high-density mask-ROM's, which might be faster in access speed and easier in fabrication process than the conventional ones. Therefore, this design is expected to be one of the most practical multiple-valued mask-ROM's.

  • Application of Ferroelectric Thin Films to Si Devices

    Koji ARITA  Eiji FUJII  Yasuhiro SHIMADA  Yasuhiro UEMOTO  Masamichi AZUMA  Shinichiro HAYASHI  Toru NASU  Atsuo INOUE  Akihiro MATSUDA  Yoshihisa NAGANO  Shin-ich KATSU  Tatsuo OTSUKI  Gota KANO  Larry D. McMILLAN  Carlos A. Paz de ARAUJO  

     
    PAPER-Device Technology

      Vol:
    E77-C No:3
      Page(s):
    392-398

    Characterization of silicon devices incorporating the capacitor which uses ferroelectric thin films as capacitor dielectrics is presented. As cases in point, a DRAM cell capacitor and an analog/digital silicon IC using the thin film of barium strontium titanate (Ba1-xSRxTiO3) are examined. Production and characterization of the ferroelectric thin films are also described, focusing on a Metal Organic Deposition technique and liquid source CVD.

  • A Method of Case Structure Analysis for Japanese Sentences Based on Examples in Case Frame Dictionary

    Sadao KUROHASHI  Makoto NAGAO  

     
    PAPER

      Vol:
    E77-D No:2
      Page(s):
    227-239

    A case structure expression is one of the most important forms to represent the meaning of the sentence. Case structure analysis is usually performed by consulting case frame information in a verb dictionary. However, this analysis is very difficult because of several problems, such as word sense ambiguity and structural ambiguity. A conventional method for solving these problems is to use the method of selectional restriction, but this method has a drawback in the semantic marker (SM) method --the trade-off between descriptive power and construction cost. In this paper, we propose a method of case structure analysis based on examples in case frame dictionary This method uses the case frame dictionary which has some typical example sentences for each case frame, and it selects a proper case frame for an input sentence by matching the input sentence with the examples in the case frame dictionary. The best matching score, which is utilized for selecting a proper case frame for a predicate, can be considered as the score for the case structure of the predicate. Therefore, when there are two or more readings for a sentence because of structural ambiguity, the best reading of a sentence can be selected by evaluating the sum of the scores for the case structures of all predicates in a sentence. We report on experiments which shows that this method is superior to the conventional, coarse-grained SM method, and also describe the superiority of the example-based method over the SM method.

621-640hit(686hit)