In content-based image retrieval (CBIR), the content of an image can be expressed in terms of different features such as color, texture, shape, or text annotations. Retrieval methods based on these features can be varied depending on how the feature values are combined. Many of the existing approaches assume linear relationships between different features, and also require users to assign weights to features for themselves. Other nonlinear approaches have mostly concentrated on indexing technique. While the linearly combining approach establishes the basis of CBIR, the usefulness of such systems is limited due to the lack of the capability to represent high-level concepts using low-level features and human perception subjectivity. In this paper, we introduce a Neural Network-based Image Retrieval (NNIR) system, a human-computer interaction approach to CBIR using the Radial Basis Function (RBF) network. The proposed approach allows the user to select an initial query image and incrementally search target images via relevance feedback. The experimental results show that the proposed approach has the superior retrieval performance over the existing linearly combining approach, the rank-based method, and the BackPropagation-based method.

A Fourier-optics based imaging system for electromagnetic interference (EMI) sources is presented. It is necessary to decrease undesired emissions in order to meet EMI requirements. To investigate this problem, a visualization of electromagnetic (EM) emitting fields is very useful. In this paper, we propose a passive imaging system of EM emitting fields based on Fourier optics. Amplitude and phase values of diffracted fields on an entrance pupil are acquired by using a six-port interferometer. The measured EM fields are then processed on a computer, and an image is retrieved using an inverse Fresnel transform. Experiments are presented, which demonstrate the potential of the proposed method. The proposed system is useful not only in the field of electromagnetic compatibility (EMC), but also for scientific elucidation to discuss the optics and microwave theory of the same viewpoint.

This paper presents a novel approach to water pollution detection from remotely sensed low-platform mounted visible band camera images. We examine the feasibility of unsupervised segmentation for slick (oily spills on the water surface) region labelling. Adaptive and non adaptive filtering is combined with density modeling of the obtained textural features. A particular effort is concentrated on the textural feature extraction from raw intensity images using filter banks and adaptive feature extraction from the obtained output coefficients. Segmentation in the extracted feature space is achieved using Gaussian mixture models (GMM).

The smart vision chip has a large potential for application in general purpose high speed image processing systems. In order to fabricate smart vision chips including photo detector compactly, we have proposed the application of three dimensional LSI technology for smart vision chips. Three dimensional technology has great potential to realize new biologically inspired systems inspired by not only the biological function but also the biological structure. In this paper, we describe our three dimensional LSI technology for biologically inspired circuits and the design of smart vision chips.

The concept of stochastic association has originally been proposed in relation to single-electron devices having stochastic behavior due to quantum effects. Stochastic association is one of the promising concepts for future VLSI systems that exceed the conventional digital systems based on deterministic operation. This paper proposes a CMOS stochastic associative processor using PWM (pulse-width modulation) chaotic signals. The processor stochastically extracts one of the stored binary patterns depending on the order of similarity to the input. We confirms stochastic associative processing operation by experiments for digit pattern association using the CMOS test chip.

Reverse link performance analyses of single-code (SC) and multi-code (MC) CDMA systems in multipath fading environments are presented. The degree of orthogonality loss among multiple spreading code channels is characterized by introducing the orthogonality factor. This factor depends on the multipath delay power profiles of the propagation channel and the number of paths resolved at a Rake receiver. The link capacity and the signal power of both CDMA systems are then analyzed according to varying system parameters, including spreading bandwidth, traffic load, the orthogonality factor, and the number of spreading codes assigned to a user. Analytical results show that the SC-CDMA system provides a larger link capacity and MC users require more power than SC users. The dominant parameters affecting the performance difference are the spreading bandwidth and multipath delay power profiles.

This paper describes performance enhancement of high-resolved delay time estimation by pattern diversity of wheel-shaped dipole antennas for the MUSIC algorithm. We propose that the wheel-shaped dipole antennas are used to average covariance matrices weightedly with their pattern diversity without decreasing the matrix dimension and to obtain freedom of selecting sweeping frequencies. It is numerically confirmed that the wheel-shaped dipole antennas can be used to enhance capability of the delay time estimation.

Elemental technologies have been studied to establish the healthcare chip which is an intelligent micro analytical system to detect human health markers from a trail of blood. A two steps process for deep quartz dry-etching was discussed in order to overcome the issues of concave-shaped defects at the bottom of grooves. A coating with 2-methacryloyloxyethylphosphorylcholine (MPC) polymer was studied to suppress the adsorption of bio-substance onto the inner wall of the flow channel on chip and good bio-compatibility was achieved for suppression of protein adsorption and blood cell adhesion. A prototype of healthcare chip was fabricated on polyethylene terephthalate (PET) plate using a micro molding technique. Using this chip, the ion concentrations of pH, Na+, K+, Ca++ were successfully measured with embedded ion sensitive field effect transistors (ISFET's).

In this paper, the sequence interference suppression characteristics of code-diversity DS/CDMA over multipath fading channels are presented. In a code-diversity system, the data signal is modulated with several PN sequences, and using these sequences at the receiver, diversity reception of the signal is carried out to suppress the influence of multiple access interference (MAI) or sequence interference (SI) especially under a near-far problem. First, in a sequence interference and AWGN environment, the basic performance of code-diversity system is presented. Next, in single-path (flat-fading) and multipath fading channels, the average BER performance of the code-diversity system is shown and the observation that the performance of code-diversity system (combined with RAKE reception) is more effective over a multipath fading channel is clarified. Finally, it is presented that by implementing adaptive weight control (AWC) for the code-diversity system over fading channels, the BER performance can further be improved.

This study is intended to realize an in-situ gas sensor based upon the principle of millimeter/submillimeter wave spectroscopy. In-situ gas sensor will be attractive because of gas selectivity, multiple parametric measurement such as gas temperature, pressure and density, and of the in-situ measurement capability. One of the major technical problem to be solved is to develop an instrument accurate enough to discern the spectrum change due to the variation of parameters such as temperature. In this paper a proposed gas absorption measurement system is investigated, which schematically consists of Fabry-Perot type gas cell for effective long path length, and vector signal processing to reject leak signal coupled between resonator input and output ports so as to achieve precise absorption measurement. Also included is an parametric study of oxygen absorption characteristics, which is served as the predicted value in the evaluation of the instrument. The experiment at 60 GHz and 120 GHz bands using oxygen demonstrates the effectiveness of the current system configuration.

This paper gives an overview of recent progress in radar polarimetry and radar polarimetric interferometry. Both techniques are of special importance for the inversion of physical scatterer parameters from radar remote sensing data. A unified treatment of polarisation effects in radar polarimetry and polarimetric interferometry based on eigenvalue processing is addressed providing a link between signal processing techniques and coherent electromagnetic models for random media scattering. In this context, the main applications of polarimetry in radar remote sensing such as single and multi-frequency polarimetric classification, the estimation of surface roughness and moisture content and vegetation structure estimation are reviewed.

We have developed a novel self-alignment process using the surface tension of the liquid resin for assembly of electronic or optoelectronic devices. Though the liquid resins have a characteristics as low as one tenth of the surface tension of solder in general, restoring forces for self-alignment capability can be produced by making it constrained on the 3-dimensional pads on chip and substrate. In this paper, its principle and characteristics are described and the relationship between process parameters and joint geometry were examined. And the possibility of self-alignment process was verified by analytic numerical method and scaled-up experiment. A self-alignment accuracy was examined experimentally and show that it became less than 0.4 µm. It can provide a useful information on various parameters involved in joint geometry and optimal design guideline to generate the proper profiles.

The VHF broadband radio interferometry operated from 25 MHz to 250 MHz has been developed for observing lightning discharge progression. The lightning images are derived by sensing the electromagnetic-waves which are radiated during the discharges. The perpendicular baseline geometry provides the angular locations (azimuth and elevation) of lightning radiation sources. The lightning observations have been conducted in the Hokuriku District in 1999. The station consisted of three broadband antennas and an electric field antenna as well as a GPS receiver. The system was able to reconstruct lightning discharge channels in two-spatial dimensions and in time sequence. As one of the observation results, an upward negative cloud-to-ground lightning flash will be presented.

Wavelet based image compression is getting popular due to its promising compaction properties at low bitrate. Zerotree wavelet image coding scheme efficiently exploits multi-level redundancy present in transformed data to minimize coding bits. In this paper, a new technique is proposed to achieve high compression by adding new zerotree and significant symbols to original EZW coder. Contrary to four symbols present in basic EZW scheme, the modified algorithm uses eight symbols to generate fewer bits for a given data. Subordinate pass of EZW is eliminated and replaced with fixed residual value transmission for easy implementation. This modification simplifies the coding technique as well and speeds up the process, retaining the property of embeddedness.

This paper investigates the interference suppression effect from much higher rate dedicated physical channels (DPCHs) of a parallel-type coherent multistage interference canceller (COMSIC) with iterative channel estimation (ICE) by laboratory experiments in the transmit-power-controlled W-CDMA reverse link. The experimental results elucidate that when two interfering DPCHs exist with the spreading factor (SF) of 8 and with the ratio of the target signal energy per bit-to-interference power spectrum density ratio (Eb/I0) of fast transmit power control, ΔEb/I0, of -6 dB (which corresponds to 64 simultaneous DPCHs with SF = 64, i.e., the same symbol rate as the desired DPCH), the implemented COMSIC receiver with ICE exhibits a significant decrease in the required transmit signal energy per bit-to-background noise power spectrum density ratio (Eb/N0) at the average bit error rate (BER) of 10-3 (while the matched filter (MF)-based Rake receiver could not realize the average BER of 10-3 due to severe multiple access interference (MAI)). It is also found that the achieved BER performance at the average BER of 10-3 of the COMSIC receiver with the A/D converter quantization of 8 bits in the laboratory experiments is degraded by approximately 1.0 dB and 4.0 dB compared to the computer simulation results, when ΔEb/I0=-6 dB and -9 dB, respectively, due to the quantization error of the desired signal and path search error for the Rake combiner. Finally, we show that the required transmit Eb/N0 at the average BER of 10-3 of the third-stage COMSIC with ICE is decreased by approximately 0.3 and 0.5 dB compared to that of COMSIC with decision-feedback type channel estimation (DFCE) with and without antenna diversity reception, respectively.

We previously developed a novel transmission power control method for code-division multiple access (CDMA) wireless systems that is suitable for the transmission control protocol (TCP) and constant bit rate (CBR) connections. It allows each mobile terminal to send packets to arbitrary slots without negotiation or the use of the ALOHA protocol. It results in high bandwidth utilization for TCP connections without the need to modify the TCP protocol or use a snoop agent. In this paper, we improve our previously developed power control method so as to adapt itself to distance variations and instantaneous fluctuations in the received power due to fading. We show that the developed method enables efficient bandwidth utilization compared with the conventional power control technique under various conditions.

We describe a method for object recognition with 2D image queries to be identified from among a set of 3D models. The pose is known from a previous step. The main target application is face recognition. The 3D models consist of both shape and color texture information, and the 2D queries are color camera images. The kernel of the method consists of a lookup table that associates 3D surface normals with expected image brightness, modulo albedo, for a given query. This lookup table is fast to compute, and is used to render images from the models for a sum of square difference error measure. Using a data set of 42 face models and 1764 (high quality) query images under 7 poses and 6 lighting conditions, we achieve average recognition accuracy of about 83%, with more than 90% in several pose/lighting conditions, using semi-automatically computed poses. The method is extremely fast compared to those that involve finding eigenvectors or solving constrained equation systems.

The packaging hierarchy is not fixed structure. It can be changed depending on the packaging technology itself, and the number of hierarchy levels tends to decrease. In LSI-package technology including package-to-board interconnections, there were two evolutionary changes. The first evolution was from PTH to SMT, and the second evolution was from "Peripheral connections" to "Area-array connections. " These evolutions have been caused by ICs integration and application products requirements. Now, the third evolution appears to be in progress, which is from SCP to MCP or SIP. Although SoC has many remarkable features, it has been not applied for many systems contrary to expectations, and its limitations or issues have become clear. SIP is the answer for above SoC's issues. MCP can be considered to be primitive SIP. The purpose of MCP is making up the technology gap between SMT and SoC to address the issues. The targets of SIP are mainly the next two items. (1) Overcoming the interconnection crisis of SoC. (2) Opening new application fields in electronics. In order to achieve those targets, several consortiums in the world are doing research and developing core technologies.

The number of computer break-ins from the outside of an organization has increased with the rapid growth of the Internet. Since many intruders from the outside of an organization employ stepping stones, it is difficult to trace back where the real origin of the attack is. Some research projects have proposed tracing methods for DoS attacks and detecting method of stepping stones. It is still difficult to locate the origin of an attack that uses stepping stones. We have developed IDA (Intrusion Detection Agent system), which has an intrusion tracing mechanism in a LAN environment. In this paper, we improve the tracing mechanism so that it can trace back stepping stones attack in the Internet. In our method, the information about tracing stepping stone is collected from hosts in a LAN effectively, and the information is made available at the public information server. A pursuer of stepping stone attack can trace back the intrusion based on the information available at the public information server on an intrusion route.

In this letter, we describe the conditions for measuring the nonlinear refractive index n2 when using the self-phase modulation-based cw dual-frequency method. We clarify the appropriate measurement conditions for dispersion-shifted and conventional single-mode fibers both numerically and experimentally. We also show experimentally that the evaluated n2 values for conventional single-mode fiber depend on the signal wavelength separation.