In this paper, analysis and synthesis methods of emotional voice for man-machine natural interface is developed. First, the emotional voice (neutral, anger, sadness, joy, dislike) is analyzed using time-frequency representation of speech and similarity analysis. Then, based on the result of emotional analysis, a voice with neutral emotion is transformed to synthesize the particular emotional voice using time-frequency modifications. In the simulations, five types of emotion are analyzed using 50 samples of speech signals. The high average discrimination rate is achieved in the similarity analysis. Further, the synthesized emotional voice is subjectively evaluated. It is confirmed that the emotional voice is naturally generated by the proposed time-frequency based approach.

In this paper, we present an efficient downlink power control scheme, for wireless networks, based on two key ideas: (i) global-local fixed-point-approximation technique (GLOFPAT) and (ii) bottleneck removal criterion (BRC). The proposed scheme copes with all scenarios including infeasible case where no power allocation can provide all multiple accessing users with target quality of service (QoS). For feasible case, the GLOFPAT efficiently computes a desired power allocation which corresponds to the allocation achieved by conventional algorithms. For infeasible case, the GLOFPAT offers valuable information to detect bottleneck users, to be removed based on the BRC, which deteriorate overall QoS. The GLOFPAT is a mathematically-sound distributed algorithm approximating desired power allocation as a unique fixed-point of an isotone mapping. The unique fixed-point of the global mapping is iteratively computed by fixed-point-approximations of multiple distributed local mappings, which can be computed in parallel by base stations respectively. For proper detection of bottleneck users, complete analysis of the GLOFPAT is presented with aid of the Tarski's fixed-point theorem. Extensive simulations demonstrate that the proposed scheme converges faster than the conventional algorithm and successfully increases the number of happy users receiving target QoS.

In this paper, we propose a novel QoS (Quality of Service) estimation scheme for JPEG 2000 coded image at RTP (realtime transfer protocol) layer without decoding the image. QoS of streaming video is estimated in view of several points, such as, transmission delay, or quality of received images. In this paper, we evaluate the QoS in terms of quality of received images. Generally, RTP is carried on top of UDP, and hence, quality of transmitted images could be degraded due to packet loss. To estimate the quality of received JPEG 2000 coded image without decoding, we use RTP header extension in order to send additional information to the receiver. The effectiveness of the proposed method is confirmed by the computer simulations.

DC motors are indispensable to improve the automotive functions. Recently, 70-100 motors are installed on luxury cars and this number is increasing year by year. With the recent demand for improved fuel economy and better equipment layout, the improvement of the motor's efficiency and the minimization of the motor size are the key to enhancing the competitive edge of the products. Adopting the high-density coil is an effective method for that, but it is accompanied by the commutation inductance rise which causes the commutation arc increase. The increase of commutation arc decreases motor life, because it causes the rise of brush/commutator wear. This report describes an arc-reducing effect obtained when capacitors are built into a commutation circuit for the purpose of reducing arcing under high commutation inductance conditions. The results of an evaluation using a equivalent commutation circuit and carbon brush/carbon flat-commutator showed that although a commutation circuit with built-in capacitor generated the same arc energy as a commutation circuit without a capacitor above a certain value of residual current, it displayed an excellent arc-reducing effect below that value of residual current.

This letter proposes a compensation method that can alleviate the problem of I/Q mismatch generated in the direct-conversion receiver of OFDM systems. In the proposed method, the amount of I/Q mismatch is estimated using null-carriers in transmitted signals, and it is subtracted from received symbols to suppress I/Q mismatch effects. Simulations show experiments that the proposed method can effectively eliminate the I/Q mismatch effects.

In this paper, we present a method for recognition of human activity as a series of actions from an image sequence. The difficulty with the problem is that there is a chicken-egg dilemma that each action needs to be extracted in advance for its recognition but the precise extraction is only possible after the action is correctly identified. In order to solve this dilemma, we use as many models as actions of our interest, and test each model against a given sequence to find a matched model for each action occurring in the sequence. For each action, a model is designed so as to represent any activity containing the action. The hierarchical hidden Markov model (HHMM) is employed to represent the models, in which each model is composed of a submodel of the target action and submodels which can represent any action, and they are connected appropriately. Several experimental results are shown.

A novel fabrication technology for lateral scale-down of sub-100-nm-gate InP-based HEMTs is presented. The fabricated device, whose structure features a reduced distance between the gate and ohmic metals of less than 100 nm, exhibits low ohmic resistances and improved DC and RF characteristics with good uniformity across a wafer. A fabricated 130-nm-gate lattice-matched InAlAs/InGaAs HEMT exhibits an extrinsic transconductance of 1.3 S/mm. This is 25% increase compared to that of a HEMT fabricated with our conventional process, which is explained by the reduction of RS. The average current-gain-cutoff-frequency (fT) of 261 GHz was obtained with a small deviation of 9.0 GHz. Uniform characteristics with high yield were also confirmed for HEMTs with shorter gates. The average fT of 290 GHz with a standard deviation of 9.3 GHz was obtained for 55-nm-gate HEMTs. The developed fabrication technology is promising for improving the electrical characteristics of sub-100-nm-gate InP-based HEMTs and for their integration.

In this paper we propose a chip-level receiver for optical frequency hopping code-division multiple-access (FH-OCDMA) systems. The proposed chip-level receiver for FH-OCDMA consists of an arrayed waveguide grating (AWG), and photo-detector (PD) for each mark chip, and uses the principles of the chip-level receiver. We analyze the error rate performance of the FH-OCDMA system with the proposed chip-level receiver with treating APD noise, thermal noise, and multi-user interference (MUI) using a Gaussian approximation. We compare the performance of the proposed chip-level receiver to that of the conventional correlation receiver. We show that the proposed chip-level receiver has a better bit error probability and can accommodate more users than the conventional correlation receiver.

In order to improve the forward link capacity of cdma2000 HRPD (High Rate Packet Data) or CDMA2000 1xEV-DO, it is significant to overcome multi-path interference. This paper focuses on FDE (Frequency Domain Equalization) with MMSE (Minimum Mean Square Error) criterion. On top of that, backward compatibility with HRPD should be maintained, in other words common channels such as the pilot channel should not be changed. Thus, the PN (Pseudo Noise) spread pilot block without CP (Cyclic Prefix) signals has to be dealt with for FDE. However, this will cause the conventional channel estimation accuracy to deteriorate. In order to improve the estimation accuracy of the conventional method, this paper presents a MRC (Maximal Ratio Combining) spectrum estimator, IPI (Inter-Path Interference) canceller, and path searcher. The results obtained from computer simulations reveal that the proposed method can improve the PER (Packet Error Rate) performance significantly. If compared with Rake combiner and TDE (Time Domain Equalization) with NLMS (Normalized Least Mean Square) scheme, the maximum data rates at a fixed PER of 1% can be increased by 5 to 8 times and 1.25 to 2.67 times, respectively.

In this letter we present steady-state analyses of a gradient algorithm (GA) for second-order adaptive infinite impulse response (IIR) notch filters. A method for deriving more accurate estimation mean square error (MSE) expressions than the recently proposed method is presented. The method is based on the estimation error power spectral density (PSD). Moreover, an expression for the estimation bias for the adaptive IIR notch filter with constrained poles and zeros is shown to be obtained from the estimation MSE expression. Simulations are presented to confirm the validity of the analyses.

A lexicon is an important linguistic resource needed for both shallow and deep language processing. Currently, there are few machine-readable Thai dictionaries available, and most of them do not satisfy the computational requirements. This paper presents the design of a Thai lexicon named the TCL's Computational Lexicon (TCLLEX) and proposes a method to construct a large-scale Thai lexicon by re-using two existing dictionaries and a large number of texts on the Internet. In addition to morphological, syntactic, semantic case role and logical information in the existing dictionaries, a sort of semantic constraint called selectional preference is automatically acquired by analyzing Thai texts on the web and then added into the lexicon. In the acquisition process of the selectional preferences, the so-called Bayesian Information Criterion (BIC) is applied as the measure in a tree cut model. The experiments are done to verify the feasibility and effectiveness of obtained selection preferences.

Coexisting with many concurrent narrowband services, the performance of UWB systems will be affected considerably by them. Specifically, IEEE 802.11a systems which operate around 5 GHz and overlap the band of UWB signals will interfere with UWB systems significantly. In this paper, a novel narrow-band interferences (NBI) suppression technique based on singular value decomposition (SVD) algorithm for a direct sequence ultra-wideband (DS-UWB) communication system is presented. SVD is used to approximate the interferences which then are subtracted from the received signals. The proposed technique is simple and robust. Simulation results show that the proposed new technique is very effective.

A self-starting pulse laser with an erbium-doped fiber cooled at liquid-nitrogen temperature was demonstrated. The self-starting-pulse fiber-ring laser can produce an approximately 1 ns pulse train without the need for devices for polarization control and compensation of birefringence.

This paper investigates some relations among four complexities of sequence over countably infinite alphabet, and shows that two kinds of empirical entropies and the self-entropy rate regarding a Markov source are asymptotically equal and lower bounded by the maximum number of phrases in distinct parsing of the sequence. Some connections with source coding theorems are also investigated.

The noise robustness of an audio fingerprinting system is one of the most important issues in music information retrieval by the content-based audio identification technique. In a real environment, sound recordings are commonly distorted by channel and background noise. Recently, Philips published a robust and efficient audio fingerprinting system for audio identification. To extract a robust and efficient audio fingerprint, Philips applied the first derivative (differential) to the frequency-time sequence of the perceptual filter-bank energies. In practice, however, the noise robustness of Philips' audio fingerprinting scheme is still insufficient. In this paper, we introduce an extension method of the audio fingerprinting scheme for the enhancement of noise robustness. As an alternative to frequency filtering, a type of band-pass filter, instead of a high-pass filter, is used to achieve robustness to background noise in a real situation. Our experimental results show that the proposed filter improves the noise robustness in audio identification.

Fast and accurate power bus designer (FAPUD) for multi-layers high-speed digital boards is the power supply network design tool for accurate and precise high speed board. FAPUD is constructed based on two main algorithms of the PBEC (Path Based Equivalent Circuit) model and the network synthesis method. The PBEC model exploits simple arithmetic expressions of the lumped 1-D circuit model from the electrical parameters of a 2-D power distribution network. The circuit level design based on PBEC is carried with the proposed regional approach. The circuit level design directly calculates and determines the size of on-chip decoupling capacitors, the size and the location of off-chip decoupling capacitors, and the effective inductances of the package power bus. As a design output, a lumped circuit model and a pre-layout of the power bus including a whole decoupling capacitors are obtained after processing FAPUD. In the tuning procedure, the board re-optimization considering simultaneous switching noise (SSN) added by I/O switching in can be carried out because the I/O switching effect on a power supply noise can estimate for the operation frequency range with the lumped circuit model. Furthermore, if a design changes or needs to be tuned, FAPUD can modify design by replacing decoupling capacitors without consuming other design resources. Finally, FAPUD is accurate compared with conventional PEEC-based design tools, and its design time is 10 times faster than that of conventional PEEC-based design tools.

A second-order CMOS continuous-time bandpass filter with a tuneable 4-12 MHz center frequency (fc) is presented. The Design has been done by using a new second-order block which is based on Gm-C method. This Gm-C filter achieves a dynamic range of 30 dB for 1% IM3, and Q equal to 58 at 12 MHz, while dissipating only 10.5 mW from 3.3 V power supply in 0.35 µm CMOS process. The on-chip indirect automatic tuning circuit uses a phase-locked loop which sets filter center frequency to an external reference clock.

The crucial issue for mobile Internet services is to provide the guaranteed mobile QoS for multicalls. In mobile networks, we should not only guarantee handoff dropping probability but also maximize resource utilization. In this paper, we propose a QoS admission control mechanism for macro Mobile QoS based on a dynamic resource reservation. We introduce the requirements for macro Mobile QoS as mobility features and predict required resources in each routing paths thorough the combined analysis of average movement pattern and pre-defined handoff dropping probability. Our simulation results show that the proposed scheme can guarantee the pre-defined handoff dropping probability and maintain lower call blocking probability and higher resource utilization than other schemes. The propose scheme gives a practical solution for mobile networks providing mobile Internet services.

This letter proposes a low-complexity single frequency estimator for flat fading channels. The simplified estimator decreases the number of computations in the calculation of the autocorrelation function (AF) when compared to AF-based conventional estimators. The simplified estimator yields a comparable estimation performance to the existing estimators, while retaining the same frequency range.

We fabricate a 763-nm laser module based on second-harmonic generation using a direct-bonded quasi-phase-matched LiNbO3 ridge waveguide. We obtained a 0.84-mW output of 763 nm light using a 1526-nm distributed-feedback laser diode. We also demonstrate O2 gas detection using the module output.