We propose in this paper a SOM-like algorithm that accepts online, as inputs, starts and ends of viewing of a multimedia content by many users; a one-dimensional map is then self-organized, providing an approximation of density distribution showing how many users see a part of a multimedia content. In this way "viewing behavior of crowds" information is accumulated as experience accumulates, summarized into one SOM-like network as knowledge is extracted, and is presented to new users as the knowledge is transmitted. Accumulation of multimedia contents on the Internet increases the need for time-efficient viewing of the contents and the possibility of compiling information on many users' viewing experiences. In the circumstances, a system has been proposed that presents, in the Internet environment, a kind of summary of viewing records of many viewers of a multimedia content. The summary is expected to show that some part is seen by many users but some part is rarely seen. The function is similar to websites utilizing "wisdom of crowds" and is facilitated by our proposed algorithm.

This paper describes the distortion properties created by self-phase modulation in super wideband FM converted 40 AM/30 64-QAM CATV and super-high-frequency RF converted 8 BS/12 CS TV signal transmission based on the optical SSB modulation scheme.

This study introduces the fuzzy Lyapunov function to the fuzzy PID control systems, modified fuzzy systems, with an optimized robust tracking performance. We propose a compound search strategy called conditional linear matrix inequality (CLMI) approach which was composed of the proposed improved random optimal algorithm (IROA) concatenated with the simplex method to solve the linear matrix inequality (LMI) problem. If solutions of a specific system exist, the scheme finds more than one solutions at a time, and these fixed potential solutions and variable PID gains are ready for tracking performance optimization. The effectiveness of the proposed control scheme is demonstrated by the numerical example of a cart-pole system.

A robust 1T1C FeRAM sensing technique is demonstrated that employs both word base access and reference level generation architecture to track the thermal history of the cells by utilizing a Feedback inverter Input Push-down (FIP) method for a Bit line Ground Sensing (BGS) pre-amplifier and a self-timing latch Sense Amplifier (SA) which is immune to increasing non-switching charges due to thermal depolarization or imprint of ferroelectric capacitor. The word base access unit consists of one 2T2C cell that stores 0/1 data and also generates '0' and '1' reference levels by which other 1T1C signals are compared. A 0.18-µm CMOS 3-V 1-Mbit device was qualified by a 250 bake for a short time retention and 150 1000-hour bake which is an accelerated equivalent to 10-years retention. It endured 1012 fatigue cycles with an access time of 81 ns, 3.0 V VDD at 85. Also a Smart Card application chip which is embedded with the 1-Mbit FeRAM macro showed 30% faster download time than one with EEPROM.

Collaboration of growing self-organizing maps (GSOM) and adaptive resonance theory maps (ART) is considered through traveling sales-person problems (TSP).The ART is used to parallelize the GSOM: it divides the input space of city positions into subspaces automatically. One GSOM is allocated to each subspace and grows following the input data. After all the GSOMs grow sufficiently they are connected and we obtain a tour. Basic experimental results suggest that we can find semi-optimal solution much faster than serial methods.

We propose a new label recognition system for photonic label switching using self-routing of labels. Binary-coded labels in on-off keying format are considered. The system consists of an all-optical demultiplexer (DeMUX) and an address recognition unit (ARU) consisting of tree-structured switches. The system uses self-routing propagation of an indication bit controlled with address bits. The indication bit is placed in advance of the address bits in the label. In DeMUX, all-optical switches in a configuration of Mach-Zehnder interferometer with semiconductor optical amplifiers (SOA-MZI) are controlled by the indication bit pulse to separate each of the label bits. The indication bit pulse is routed to the destination output port corresponding to the code of the address in ARU. It is shown that all the binary number codes can be recognized with this system. The operation principle is verified by numerical simulation using coupled-mode theory and a rate equation. Moreover, the switching crosstalk is also evaluated.

This paper presents a novel technique to compensate intermodulation distortion of a self-heterodyne direct conversion OFDM system in multipath propagation environments. A self-heterodyne direct conversion system has an advantage that simple receivers can be built that are completely immune to any phase noise or frequency offset. This system, however, has a disadvantage that the nonlinear square-law detector at the receiver of the self-heterodyne direct conversion system gives rise to second order intermodulation distortion. In this study, channel estimation is performed using a training sequence and then the predistortion coefficients with regard to estimated channel parameters are derived to compensate the receiver nonlinearity. Transmit power distribution is employed to overcome multipath fading channels as well. Computer simulation demonstrates that the proposed approach improves the BER performance of the self-heterodyne direct conversion OFDM system in a multipath fading channel. This scheme gives advantage to multi-carrier systems that are much more sensitive to frequency and phase error than single-carrier systems.

Data detection based on self organizing maps is presented for hematopoietic tumor patients. Learning data for the maps are generated from the screening data of examinees. The incomplete screening data without some item values is then supplemented by substituting averaged non-missing item values. In addition, redundant items, which are common to all the data and tend to have an unfavorable influence on data detection, are eliminated by a genetic algorithm and/or an immune algorithm. It is basically judged, by observing the label of a winner neuron in the map, whether the data presented to the map belongs to the class of hematopoietic tumors. Some experimental results are provided to show that the proposed methods achieve the high probability of correctly identifying examinees as hematopoietic tumor patients.

In this paper, a novel independent component analysis (ICA) approach is proposed, which is robust against the interference of impulse noise. To implement ICA in a noisy environment is a difficult problem, in which traditional ICA may lead to poor results. We propose a method that consists of noise detection and image signal recovery. The proposed approach includes two procedures. In the first procedure, we introduce a self-organizing map (SOM) network to determine if the observed image pixels are corrupted by noise. We will mark each pixel to distinguish normal and corrupted ones. In the second procedure, we use one of two traditional ICA algorithms (fixed-point algorithm and Gaussian moments-based fixed-point algorithm) to separate the images. The fixed-point algorithm is proposed for general ICA model in which there is no noise interference. The Gaussian moments-based fixed-point algorithm is robust to noise interference. Therefore, according to the mark of image pixel, we choose the fixed-point or the Gaussian moments-based fixed-point algorithm to update the separation matrix. The proposed approach has the capacity not only to recover the mixed images, but also to reduce noise from observed images. The simulation results and analysis show that the proposed approach is suitable for practical unsupervised separation problem.

A new digital calibration scheme for a 14 bit binary weighted current-steering digital-to-analog converter (DAC) is presented. This scheme uses a simple current comparator for the current measurement instead of a high-resolution ADC. Therefore, a faster calibration cycle and smaller additional circuits are possible compared to the scheme with the high-resolution ADC. In the proposed calibration scheme, the lowest 8 bit part of the DAC is used for both error correction and normal operation. Therefore, the extra DACs required for calibration are only a 3 bit DAC and a 6 bit DAC. Nevertheless, a large calibration range is achieved. Full 14 bit resolution is achieved with a small chip-area. The simulation results show that DNL and INL after calibration are 0.26 LSB and 0.46 LSB, respectively. They also show that the spurious free dynamic range is 83 dB (57 dB) for signals of 24 kHz (98 MHz) at 200 Msps update rate.

The potential of optical circuit packaging technology is discussed. Special attention is paid to introduction of "optical wiring" at the printed wiring board level (i.e., in the "last 1 meter area") to overcome the bandwidth limitations of electrical copper-based wiring. The suitability of optical surface mount technology (O-SMT) as a possible solution is reviewed. It is shown that the key to the utility of O-SMT is high efficiency and alignment-free coupling between optical wiring and optical devices. O-SMT requires a method to change the beam direction from the horizontal to the vertical and vice versa in order to couple optical wiring in an OE-board and OE-devices mounted on the board. A novel method using an "optical pin" is proposed and investigated. Furthermore, an optical coupling method using a self-written waveguide called "optical solder" is reviewed. Several applications of self-written waveguides using a green laser and a photo-mask are demonstrated.

Twin-Channel (TC)-MOSFET with twin omega-gate (Ω-gate) Si channels and its fabrication process were proposed. The twin Si channels are able to be fabricated by self-aligned process utilizing wet etching of SiN and silicon-on-insulator (SOI) wafers. Three-dimensional (3-D) device simulation was performed to optimize gate structure for TC-MOSFET with 10 nm10 nm (TSiWG) channels with the gate length of 30 nm, and it was found that TC-MOSFET with right-angled Ω-gate in case the Lunder was 3 nm showed excellent device characteristics similar to the gate-all-around (GAA) devices corresponding to the gate structure as Lunder=5 nm. Fabrication process of twin Si channels was also investigated experimentally, and approximately 40 nm40 nm twin Si channels were successfully fabricated on SOI by the proposed fabrication process.

Light-induced self-written (LISW) technology is a unique and simple method of forming low-loss 3-dimensional (3-D) optical circuits in photopolymers using radiation from an optical fiber. Since this technology is applicable to almost all kinds of optical fiber and optical wiring, many studies have been carried in a number of different organizations on the applications of this technology. The technology helps simplify optical interconnections, and it is expected that it will reduce the cost of mounting optical devices. In this paper, we introduce LISW technology and report on related studies developed in our research group.

In order to reconstruct 3-D Euclidean shape by the Tomasi-Kanade factorization, one needs to specify an affine camera model such as orthographic, weak perspective, and paraperspective. We present a new method that does not require any such specific models. We show that a minimal requirement for an affine camera to mimic perspective projection leads to a unique camera model, called symmetric affine camera, which has two free functions. We determine their values from input images by linear computation and demonstrate by experiments that an appropriate camera model is automatically selected.

Recently, self-reconfigurable devices which can be partially reprogrammed by other part of the same device have been proposed. However, since conventional self-reconfigurable devices are LUT-array-based fine-grained devices, their time efficiency is spoiled by overhead for reconfiguration time to load large amount of configuration data. Therefore, we have to improve architectures. At the architecture design phase, it is difficult to estimate the performance, including reconfiguration overhead, of self-reconfigurable devices by static analysis, since it depends on many architecture parameters and unpredictable run-time behavior. In this paper, we propose a simulation-based platform for design exploration of self-reconfigurable devices. As a demonstration of the proposed platform, we implement an adaptive load distribution model on the devices of various reconfiguration granularities and evaluate performance of the devices.

The Self-Organizing Map (SOM) is an unsupervised neural network introduced in the 80's by Teuvo Kohonen. In this paper, we propose a method of simultaneously using two kinds of SOM whose features are different (the nSOM method). Namely, one is distributed in the area at which input data are concentrated, and the other self-organizes the whole of the input space. The competing behavior of the two kinds of SOM for nonuniform input data is investigated. Furthermore, we show its application to clustering and confirm its efficiency by comparing with the k-means method.

This paper describes a method of reducing substrate noise and random variability utilizing a self-adjusted forward body bias (SA-FBB) circuit. To achieve this, we designed a test chip (130 nm CMOS 3-well) that contained an on-chip oscilloscope for detecting dynamic noise from various frequency noise sources, and another test chip (90 nm CMOS 2-well) that contained 10-M transistors for measuring random variability tendencies. Under SA-FBB conditions, it reduced noise by 35.3-69.8% and reduced random variability σ (Ids) by 23.2-57.9%.

We develop a maximum likelihood estimation scheme for correcting the carrier frequency offsets prior to the general intercarrier interference (ICI) self-cancellation in the OFDM systems. Since the same data symbols employed for ICI self-cancellation are also used for frequency offset estimation, the proposed scheme does not consume additional bandwidth. The combined use of the estimation algorithm and ICI self-cancellation scheme provides both frequency offset compensation and ICI reduction hence improves the system performance greatly. The effectiveness of the proposed estimation-cancellation scheme is further verified by calculating the bit error rates of various OFDM receivers, and substantial improvements are found.

Performance analysis of ultra-fast all-optical analog-to-digital converter using optical multiple-level thresholding module based on self-frequency shift in fiber is described. In analog-to-digital conversion, the purposes of optical sampling and optical quantization are in the possibility of the speed-up of sampling and quantization processes using various ultra-fast nonlinear phenomena depending on an intensity of a light. The result of analysis indicates that the number of achievable quantized levels of the proposed approach is in the increasing tendency with an increase in the peak power of an input pulse.

We propose and demonstrate the all-optical analog-to-digital conversion (ADC) using optical delay line encoders. Experimental results show that input analog signals are successfully converted into 3-bit digital signals at a bit rate of 40 Gb/s.