IEEJ Transactions on Electronics, Information and Systems
Online ISSN : 1348-8155
Print ISSN : 0385-4221
ISSN-L : 0385-4221
Volume 127 , Issue 9
Showing 1-30 articles out of 30 articles from the selected issue
Special Issue on “Nanoscience and Nanotechnology Using Photo-Related Quantum Fields”
Special Issue Paper
<Optoelectronics & Quantum Electronics>
  • Yusuke Katayama, Ryouki Watanabe, Tomohiro Kobayashi, Takashi Meguro, ...
    2007 Volume 127 Issue 9 Pages 1294-1297
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    The ErSi2 nanowires were formed on Si (110) substrates by a self-assembled growth process without a high vacuum system. All of the nanowires were highly parallel and along the Si [1-10] direction. It was shown by structural analysis that the nanowires consisted of two types, which showed a similar surface morphology. The first type is ErSi2 nanowires buried into the Si substrate by a depth of 30nm, and the other is ErSi2 thin layers covering on wire-like Si surface. The later is suggested to be the remained structure after evaporation of the first type wires during the high temperature annealing.
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  • Hana Jimbow, Chikara Yatabe, Kenichi L. Ishikawa, Yasufumi Yamada, Koj ...
    2007 Volume 127 Issue 9 Pages 1298-1303
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    We present efficient design of subwavelength diffractive optical elements (DOEs) based on finite-difference time-domain (FDTD) method and optimization by genetic algorithm (GA). Using the GA-FDTD method, we successfully optimize the structure of polarizing beam splitter (PBS) and focusing lens. We also show design of hybrid functional DOEs that double as PBS and lens.
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  • Koumei Nagai, Yoshinori Iketaki, Andrew Domondon, Yu Sato, Tsutomu Wat ...
    2007 Volume 127 Issue 9 Pages 1304-1307
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    It is well known that transitions such as 1s-to-π* transitions possess an angular dependence. In particular, the transition is optically forbidden at the normal-incidence angle because the electric vector of X-ray is perpendicular to the π* molecular orbital. This means that compounds possessing π* molecular orbitals, such as graphite, become transparent at the normal-incidence angle. Using this optical property, we propose a design for a metal/graphite normal-incidence X-ray multilayer device. It is expected that the designed mirror will have a reflectance of 35% in the XANES region of carbon. Finally, we consider an application of the mirror to biological X-ray microscopy.
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  • Yasunori Toda, Koshi Nagaoka, Katsuhiro Shimatake, Ryuji Morita
    2007 Volume 127 Issue 9 Pages 1308-1313
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Topology has become one of the key concepts allowing one to understand the intrinsic, qualitative properties of phenomena throughout various scientific fields. To date, this concept has been extended to the field of material science and technology. On the other hand, we can now utilize the spatially-controlled light defined by the topology (so called “optical vortices”) in order to characterize the topological properties of materials. Especially, optical vortices in the femtosecond pulses will be invaluable for advanced topological spectroscopy. In this work, we created femtosecond optical vortices using spatial light modulator. Their spatio-temporal properties were evaluated using interferogram and correlation measurements.
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<Control and Measurement>
  • Seiji Higuchi, Olivier Laurent, Kenichi Obori, Tomonobu Nakayama
    2007 Volume 127 Issue 9 Pages 1314-1319
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Multiple-scanning-probe microscopes (MPSPMs) are one of the powerful tools which can measure physical properties of nanostructures and nanodevices. However, it is, in general, difficult to operate multiple probes in a nanoscale region and to measure probe-to-probe distance before the actual property measurements. To solve such difficulty, we have developed a control system specialized for multiple-scanning-probe measurements and used the system with our home-made MPSPM operated in air. In this paper, we report that how to realize safe and easy recognition for nanoscale positional relationship between four probes by applying sample scanning method. we show, for the first time, simultaneously acquired four STM images using four independently-controlled probes. All of the four images involve the identical area on the sample surface, indicating that the four probes have scanned over the same area. Using the four STM images, we have calculated the shift vectors which describe nanoscale positional relationships between the four STM images, in other words, between four probe-to-sample contact points. This is an important achievement towards further applications of MPSPM measurements in nanotechnology.
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Special Issue Material
<Electronic Materials>
  • Yoshitaka Shingaya, Tomonobu Nakayama
    2007 Volume 127 Issue 9 Pages 1320-1323
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Nanorods of substoichiometric tungsten oxide (WOx) were grown on single crystal tungsten substrate. The grown nanorods were investigated with scanning electron micrope and atomic force microscope. WOx nanorods were grown on W(001) in accordance with epitaxial relationship between WO3 crystals and W(001) surface. The results indicate that the WO3 crystals formed at the initial stage act as the nuclei of WOx nanorods. Nanorod growth of certain epitaxial directions can be selectively enhanced by choosing growth methods or choosing suitable crystallographic orientation of substrate surface.
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  • Jun Onoe
    2007 Volume 127 Issue 9 Pages 1324-1328
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    When a C60 film was irradiated with an electron-beam with an incident energy of 3 kV and with an current intensity of 0.5 mA under a ultrahigh vacuum condition, a peanut-shaped C60 polymer with a negative Gauss curvature was formed and exhibits a metallic I-V characteristics in air at room temperature. In the present paper, we review the electronic and electric properties of a peanut-shaped C60 polymer using in situ photoelectron spectroscopy and in situ four-probe measurements, together with density-functional calculations of some peanut-shaped C60 polymer model structures, and describe the π-electron conjugated systems from a standpoint of topology.
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  • Takashi Meguro
    2007 Volume 127 Issue 9 Pages 1329-1333
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Nanoscale modification of electronic states of highly oriented pyrotytic graphite (HOPG) surfaces induced by the impact of slow highly charged ion (HCI) is reviewed. The high potential energy of slow Ar8+ induces multiple emission of electrons from the surface, which strongly modifies the electronic states of the local area of HOPG surfaces. The size of created protrusions created by the Ar8+-impact with 400 eV of the kinetic energy was about 1 nm in diameter, and the subsequent surface treatment by electron injection from a scanning tunneling microscope (STM) induced a localized transition from sp2 to sp3 hybridization at the center of the protrusion, which considered to result in the formation of nano-diamond-like structures.
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<Optoelectronics & Quantum Electronics>
  • Masashi Ishii
    2007 Volume 127 Issue 9 Pages 1334-1339
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    For selective analyses of nano structures, an x-ray analysis in which x-ray induced photoionization of electron localizing sites is probed with capacitance (C) or electrostatic force (EF) is proposed. The photoionization of nano structures with localized electrons provides a quasi-stable state with a long lifetime of > ms. The photoionization is rapidly relaxed to initial state within ˜fs at the other sites without localized electrons. Because of high sensitivity of C and EF to the quasi-stable state with long lifetime, selective analyses of nano structure can be achieved. We demonstrate this technique with samples of Cu metal and chemically deposited Si oxide film. We observe the modulation of C and EF with a parallel plate capacitor and electrostatic force microscopy. The C modulation dependent on x-ray photon energy indicated an electronic state of Cu/Cu2O interface, and the EF modulation realized stoichiometry mapping of thin SiOx film on Si wafer.
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Special Issue Letter
<Electronic Materials>
  • Andrew Domondon, Yoshinori Iketaki, Koumei Nagai, Yu Sato, Tsutomu Wat ...
    2007 Volume 127 Issue 9 Pages 1340-1341
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    XANES region optical properties of the following four carbon compounds with π* molecular orbitals are investigated: C60, C70, a carbon nanotube, and graphite. To determine the real and imaginary parts of the optical constants of the above, the atomic-scattering factors of these compounds near the K-edge of carbon are calculated using observed XANES spectra data and the Hartree-Slater method. Anomalous dispersions are observed in the real and imaginary parts of the optical constants near the K-edge. Each of the compounds are found to possess refractive indices that vary sharply with photon energy. In fact, we provide optical data for these four compounds that has not previously been given anywhere else.
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  • Mami Yamada, Ryuji Ohkawa, Mikio Miyake
    2007 Volume 127 Issue 9 Pages 1342-1343
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    In this communication, we demonstrate the novel preparation of alloy metal nanoparticles using a nanometer-sized metal coordination polymer (MCNP) as a precursor. The presented method works effectively for the construction of an uncommon alloy nanoparticle such as a IV semiconductor-transition metal alloy. Iron trisoxalategermanium MCNPs stabilized by stealylamine (SA) were newly synthesized in reverse micelle technique, and Ge-ox-Fe-SA was successfully transformed into GeFe1.4 alloy metal nanoparticles by a gas phase reduction of metal sites under H2, accompanied by the removal of the bridging oxalate ligands. The prepared GeFe1.4 nanoparticles exhibited unique ferromagnetic behavior.
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<Integrated Electronic-Circuits>
  • Yoshinori Iketaki, Takeshi Watanabe, Yutaka Yoribayashi, Sadafumi Kaji ...
    2007 Volume 127 Issue 9 Pages 1344-1345
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    To reduce a measurement time in scanning microscope using pulse laser light source, we developed a novel measurement system. In the system, address data of sample stage signal are detected together with a sign from a sample. Using this system, a fluorescence image of a nano-scale with 250nm L&S line pattern was measured with a positioning accuracy of 40nm. A contrast of the image with 100×100 pixels corresponds to that for the diffraction limit of an objective lens. It takes only 20 sec for obtaining one image with a good S/N. It is expected the system contribute to microscopy applied in a research field concerning nano-science.
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<Optoelectronics & Quantum Electronics>
Paper
<Optoelectronics & Quantum Electronics>
  • Kaoru Suzuki
    2007 Volume 127 Issue 9 Pages 1352-1357
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Biomaterial, such as chitosan, poly lactic acid, etc., containing fluorescence agent was deposited onto biology hard tissue, such as teeth, fingernail of dog or cat, or sapphire substrate by free electron laser induced forward transfer method for direct write marking. Spin-coated biomaterial with fluorescence agent of rhodamin-6G or zinc phthalochyamine target on sapphire plate was ablated by free electron laser (resonance absorption wavelength of biomaterial : 3380 nm). The influence of the spin-coating film-forming temperature on hardness and adhesion strength of biomaterial is particularly studied. Effect of resonance excitation of biomaterial target by turning free electron laser was discussed to damage of biomaterial, rhodamin-6G or zinc phtarochyamine for direct write marking
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<Biomedical Engineering>
  • Jianming Lu, Jiang Liu, Xueqin Zhao, Takashi Yahagi
    2007 Volume 127 Issue 9 Pages 1358-1365
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    In this paper, a pyramid recurrent neural network is applied to characterize the hepatic parenchymal diseases in ultrasonic B-scan texture. The cirrhotic parenchymal diseases are classified into 4 types according to the size of hypoechoic nodular lesions. The B-mode patterns are wavelet transformed , and then the compressed data are feed into a pyramid neural network to diagnose the type of cirrhotic diseases. Compared with the 3-layer neural networks, the performance of the proposed pyramid recurrent neural network is improved by utilizing the lower layer effectively. The simulation result shows that the proposed system is suitable for diagnosis of cirrhosis diseases.
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<Multimedia Technology>
  • Tetsuji Haga, Kazuya Sato, Manabu Hashimoto
    2007 Volume 127 Issue 9 Pages 1366-1374
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    We propose an image processing system which searches the moving human and vehicles from the long-term surveillance video for intruder detection or parking lot monitoring, by comparing a series of retrieval queries like passing a certain area, moving direction, duration time and so on. In such a system, not only on-line detection from real-time video by pre-defined query but also quick re-search going back to the past when the user changed the query, and post-retrieval by interactive query change are required. In proposed method, we simplified the image retrieval meta-data to be described in a small and fixed length data however complicated the trajectory of moving object is. Moreover, the matching core function of image retrieval process is realized by a simple comparator. That enables fast image retrieval however complicated the series of the retrieval queries is. To test the performance of the system, we used a long-term parking lot monitoring sequence. About 34 hours after the on-line image processing started when the total number of moving objects reached to 10,000, we changed the retrieval query and restarted matching process and confirmed that the new result is listed up in less than 0.2 seconds.
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  • Yoshihiro Miyake, Kenichi Suzaki, Shinji Araya
    2007 Volume 127 Issue 9 Pages 1375-1383
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    The electronic map is very useful for navigation in the VRML/X3D virtual environments. So far various map-based interfaces have been developed. But they are lacking for generality because they have been separately developed for individual VRML/X3D contents, and users must use different interfaces for different contents. Therefore we have developed a web page that provides a common map-based interface for VRML/X3D contents on the web. Users access VRML/X3D contents via the web page. The web page automatically generates a simplified map by analyzing the scene graph of downloaded contents, and embeds the mechanism to link the virtual world and the map. An avatar is automatically created and added to the map, and both a user and its avatar are bi-directionally linked together. In the simplified map, obstructive objects are removed and the other objects are replaced by base boxes. This paper proposes the architecture of the web page and the method to generate simplified maps. Finally, experimental system is developed in order to show the improvement of flame rates by simplifying the map.
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<Sound and Image Processing and Recognition>
  • Yoshiki Terada, Fumihiko Saitoh
    2007 Volume 127 Issue 9 Pages 1384-1391
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Automatic detection of abnormal conditions in scene images is an important research theme. This paper proposes a general-purposed method for automatic detection of abnormal conditions based on the analysis of periodicity of movements. In the proposed method, cyclic movements are detected by voting binarized averaged grayscale values into each frequency. The disorder of movements, which represents the occurrence of abnormal situation, can be recognized by monitoring the change of bias conditions in voting. The experimental results showed that the reliable detections for periodicity and the speedy detections of abnormal conditions were realized in the general situations.
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<Control and Measurement>
  • Masanori Kuwahara, Shigeyasu Kawaji
    2007 Volume 127 Issue 9 Pages 1392-1399
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Although it is recognized that linear control theory has been established mostly, but depending on realistic conditions there remain unsolved control problems. As an example we will discuss the sensor selection LQ problem in this paper. Recent sensor technology makes a process to arrange many low-priced sensors possible. In such case we can expect more effective real-time control by changing sensors properly. This problem will be an essential control problem, but it has not been discussed in the literature. This is because of the combinatorial property of the problem solution. In this paper, we first propose the concept of “the comparability of sensors” and yield a result for the uniqueness of optimal solution. Next, we extend the problem in the case of use of observer and yield a sufficient condition for existence of the unique solution.
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  • Kentaro Asato, Tsutomu Nagado, Shiro Tamaki
    2007 Volume 127 Issue 9 Pages 1400-1407
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    In this paper, a new controller reduction method using generalized Gramians (generalized controllability and observability Gramians) is proposed. In order to obtain the generalized Gramians which have block diagonal structure, a considering control system is described by using right and left coprime factorizations of the plant and the controller. For the system and its subsystems (sensitivity function etc.), H error norms of the subsystems (the system) with a reduced-order controller yield an upper bound of H performance of the system (each subsystem) with the reduced-order controller. From the viewpoint of the relation, the reduced-order controllers in the proposed method are obtained with combination of the structured generalized Gramians of the subsystems. Finally, several numerical examples are used to verify the availability of the proposed method.
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  • Masahide Nomura, Yoshio Sato, Katsunori Ouchi, Ryou Kondo
    2007 Volume 127 Issue 9 Pages 1408-1418
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    This paper proposes a new prediction control method for thermal power plants. In the method, steam temperatures are predicted using prediction model of multi heat exchangers. Each model of a heat exchanger consists of a lumped parameter physical model and a dead time element. State variables of the heat exchanger are estimated using a Kalman Filter, and near future changes of steam temperatures are predicted by integrating multi heat exchanger models, and fuel flow and water spray flows are compensated accordingly.
    The results of simulation using a practical scale simulator of the thermal power plant show that the proposed method is so practical that changes of main steam temperature are reduced by half comparing with those of PID control method.
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<Robotics>
  • Toshihiko Takaya, Hidenori Kawamura, Masahito Yamamoto, Azuma Ohuchi
    2007 Volume 127 Issue 9 Pages 1419-1429
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    A blimp robot is attractive as an small flight robot and can float in the air by buoyancy and realize safe to the crash small flight with low energy and can movement for a long time compared with other flight robots with low energy and can movement for a long time compared with other flight robots. However, control of an airplane robot is difficult for the nonlinear characteristic exposed to inertia by the air flow in response to influence. Therefore, the applied research which carried out the maximum use of such in recent years a blimp robot's feature is prosperous.
    In this paper, we realized development of blimp robot for research which can be used general-purpose by carrying out clue division of the blimp robot body at a unit, and constituting and building for research of blimp robot, and application development. On the other hand, by developing a general-purpose blimp robot research platform, improvement in the research efficiency of many researchers can be attained, and further, research start of blimp robot becomes easy and contributes to development of research.
    We performed the experiments for the above-mentioned proof. 1. Checked basic keeping position performance and that various orbital operation was possible. And the unit exchange ease of software unit was checked by the experiment which exchanges the control layer of software for learning control from PID control, and carries out comparison of operation. 2. In order to check the exchange ease of hardware unit, the sensor was exchanged for the microphon from the camera, and control of operation was checked. 3. For the unit addition ease, the microphon which carries out sound detection with the picture detection with a camera was added, and control of operation was verified. 4. The unit exchange was carried out for the check of a function addition and the topological map generation experiment by addition of an ultrasonic sensor was conducted.
    Developed blimp robot for research mounted the exchange ease and the additional ease of a unit in hardware using an analog and digital I/F fomenting realized in the combination of the software module of a layered structure in software was performed. Consequently, an addition and exchange of a function were able to become easy and were able to realize the research platform of blimp robot.
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<Neural Network, Fuzzy and Chaos Systems>
  • Takashi Yamashita, Shingo Mabu, Kotaro Hirasawa, Takayuki Furuzuki
    2007 Volume 127 Issue 9 Pages 1430-1435
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Universal Learning Networks (ULNs) provide a generalized framework to many kinds of structures of neural networks with supervised learning. Multi-Branch Neural Networks (MBNNs) which use the framework of ULNs have been already shown that they have better representation ability in feedforward neural networks (FNNs). Multi-Branch structure of MBNNs can be easily extended to recurrent neural networks (RNNs) because the characteristics of ULNs include the connection of multiple branches with arbitrary time delays. In this paper, therefore, RNNs with Multi-Branch structure are proposed and they show that their representation ability is better than conventional RNNs. RNNs can represent dynamical systems and are useful for time series prediction. The performance evaluation of RNNs with Multi-Branch structure was carried out using a benchmark of time series prediction. Simulation results showed that RNNs with Multi-Branch structure could obtain better performance than conventional RNNs, and also showed that they could improve the representation ability even if they are smaller sized networks.
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<System Engineering>
  • Masaki Samejima, Yutaka Shimizu, Masanori Akiyoshi, Norihisa Komoda
    2007 Volume 127 Issue 9 Pages 1436-1441
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    We propose an extraction method of product features from press releases of companies for competitor analysis. In press releases of companies, product features are described with characteristic expressions (we call “description patterns”). From this view point, when a description pattern is input, our system extracts features included in the pattern. Additionally, in order to extract more product features by less input patterns, our system generates similar patterns of input patterns as “derivation patterns” automatically and extracts product features using derivation patterns. Through application to the press releases of ten companies, it is confirmed that the accuracy of the extracted features are sufficient.
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  • Tsutomu Okawa, Tsukasa Kaminishi, Yoshiyuki Kojima, Syuichi Hirabayash ...
    2007 Volume 127 Issue 9 Pages 1442-1451
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    Business process modeling (BPM) is gaining attention as a measure of analysis and improvement of the business process. BPM analyses the current business process as an AS-IS model and solves problems to improve the current business and moreover it aims to create a business process, which produces values, as a TO-BE model. However, researches of techniques that connect the business process improvement acquired by BPM to the implementation of the information system seamlessly are rarely reported. If the business model obtained by BPM is converted into UML, and the implementation can be carried out by the technique of UML, we can expect the improvement in efficiency of information system implementation. In this paper, we describe a method of the system development, which converts the process model obtained by BPM into UML and the method is evaluated by modeling a prototype of a parts procurement system. In the evaluation, comparison with the case where the system is implemented by the conventional UML technique without going via BPM is performed.
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<Software and Information Processing>
  • Ken-ichi Tokoro, Yasushi Masuda, Hisakazu Nishino
    2007 Volume 127 Issue 9 Pages 1452-1459
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    This paper proposes a genetic algorithm for solving a unit commitment schedule problem of electric generators, which formally is a mixed integer nonlinear programming problem. A chromosome represents a partial solution of binary variables. The fitness of an individual is evaluated based upon a solution of the problem where all free variables in the chromosome are relaxed to be continuous. Numerical experiments show that the proposed algorithm outperforms Lagrangian relaxation based methods developed so far.
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  • Takashi Onoyama, Takuya Maekawa, Sen Kubota, Setsuo Tsuruta, Norihisa ...
    2007 Volume 127 Issue 9 Pages 1460-1467
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    A GA applied VRP (Vehicle Routing Problem) solving-method which realizes optimization of a cooperative logistics network is proposed. For this optimization a VRP solving-method that can obtain human expert-level solution, which realizes steady logistics operation, in interactive response time is required. The multi-stage GA enables to obtain the accurate solution under both hard and weak time constraints in interactive response time. Moreover, to realize the stable logistics operation, the daily fluctuation of shipping volume is taken into the fitness value of each individual in GA. The experimental result reveals the proposed method obtains the accurate solution that realizes the stable operation in interactive response time.
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  • Takeru Yokoi, Hidekazu Yanagimoto, Sigeru Omatu
    2007 Volume 127 Issue 9 Pages 1468-1473
    Published: September 01, 2007
    Released: September 05, 2007
    JOURNALS FREE ACCESS
    We propose an information filtering system with extracted index words using by Independent Component Analysis(ICA). Elements of a document vector are established as the weights of index words and their dimensions become larger as the number of documents is increased. Therefore, from the view point of processing time and memory space, the dimension must be decreased. The proposed method decreases the dimension by selecting the index words based on the topics included in the corpus. We have applied ICA to the documents to obtain the topics. Then filtering by the relevance feedback with the document vectors reconstructed by the selected index words, was carried out to confirm the effectiveness of the proposed method.
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