As the Internet has become the infrastructure for the global communication, the quality degradation due to network failures and illegal traffic such as DDoS (Distributed Denial of Service) have become a serious problem. In order to solve the problem, a network monitoring system that monitors the traffic of Internet in real time is strongly desired. Traffic monitors that collect the statistics from captured packets play a key roll in the system; however, they are not flexible enough for being used in the rapidly changing Internet. The traditional approach such that a new traffic monitor is developed for a new requirement results in a long turn around time of the development. Therefore, we have proposed a flexible network monitoring system that consists of programmable traffic monitors. Traffic monitors are made programmable by introducing active network techniques; therefore, we call the network monitoring system as the programmable monitor network. This paper describes the implementation of the programmable monitor network and its application to DDoS (Distributed Denial of Service) attack detection.

Ultrafast all optical switching using pulse trapping by 100 fs ultrashort soliton pulse across zero dispersion wavelength is investigated. The characteristics of pulse trapping are analyzed both experimentally and numerically. Using the pulse trapping, 1 THz ultrafast all optical switching is demonstrated experimentally. Arbitral one pulse is picked off from pulse train. Pulse trapping for CW signal is also demonstrated and ultrashort pulse is generated by pulse trapping. From these investigation, it is shown that ultrafast all optical switching up to 2 THz can be demonstrated using pulse trapping.

Over the last twenty years, 3-D audio technologies have advanced significantly despite the difficulties in implementing them. However, their performance in providing information, especially about the distance of a sound source, remains imperfect. Therefore, more researches on distance cues are indispensable to achieve more effective technology. In this paper, we try to show how the conventional cues change as the distance of a sound source varies, by means of measured impulse responses using the swept-sine method and modeled impulse responses using CATT Acoustics. It is well known that the conventional cues comprise loudness, spectral information, reverberation and binaural information. Among these, we focus on the reverberation cue to describe the distance of a sound source. Some researches have shown that reverberation can give listeners absolute distance information, but the implementation using this cue is unfeasible because there are no well-defined parameters. In this paper, we also try to validate reverberation as a feasible distance cue by suggesting early decay time (EDT) and clarity index, C80, as the parameters for controlling the perceived distance with the reverberation cue.

In this paper, the effects of visual information on associated auditory information were investigated when presented simultaneously under dynamic conditions on a wide screen. Experiments of an auditory-visual stimulus presentation using a computer graphics movie of a moving patrol car and its siren sound, which were combined in various locations, were performed in 19 subjects. The experimental results showed the following: the visual stimulus at the beginning of the presentation captured the sound image stronger than that at the end (i.e., beginning effect), the sound image separated from the visual image even when both stimulus locations were exactly at the same place and then when both stimuli moved in opposite directions from each other, the visual stimulus tended to capture the sound image stronger in the peripheral visual field than in the central visual field, and the visual stimulus moving toward the sound source captured the sound image stronger than that moving away from the sound source.

This paper presents a novel class of sigma-delta modulator topologies for low-voltage, high-speed, and high-resolution applications with low oversampling ratios (OSRs). The main specifications of these architectures are the reduced analog circuit requirements, large out-of-band gain in the noise transfer function (NTF) without any stability concerns to achieve high signal to noise ratio (SNR) with a low OSR, and unity-gain signal transfer function (STF) to reduce the harmonic distortions resulted from the analog circuit imperfections. To demonstrate the efficiency of the proposed modulator architectures a prototype with HSPICE is implemented. A low-power two-stage class A/AB OTA with modified common mode feedback (CMFB) circuit in the first stage is used to implement the fourth order modulator. Simulation results with OSR of 16 give signal to noise plus distortion ratio (SNDR) and dynamic range (DR) of 90-dB and 92.5-dB including the circuit noise in the 1.25-MHz signal bandwidth, respectively. The circuit is implemented in a 0.13-µm standard CMOS technology. It dissipates about 40-mW from a single 1.2-V power supply voltage.

Dynamic non-linearities are of more importance in highly-linear high-speed applications such as software radios. In this paper, a fully-analytical approach to estimate the statistics of dynamic non-linearity parameters of pipeline analog-to-digital converters (ADCs) in the presence of circuit non-idealities is presented. These imperfections include the capacitor mismatches and the non-idealities in the operational amplifiers (op-amps). The most two important ADC dynamic non-linearity parameters, the spurious-free dynamic range (SFDR) and the signal-to-noise-and-distortion ratio (SNDR) are quantified here and closed-form formulas are presented. These formulas are useful for design automation as well as hand calculations of highly-linear pipeline ADCs. Behavioral simulations are presented to show the accuracy of the proposed equations.

This paper first discusses the misinterpretation of the concept of "ubiquitous computing" that Mark Weiser originally proposed in 1991. Weiser's main message was not the ubiquity of computers, but the transparency of interface that determines users' perception of digital technologies embedded in our physical environment seamlessly. To explore Weiser's philosophy of transparency in interfaces, this paper presents the design of an interface that uses glass bottles as "containers" and "controls" for digital information. The metaphor is a perfume bottle: Instead of scent, the bottles have been filled with music -- classical, jazz, and techno music. Opening each bottle releases the sound of a specific instrument accompanied by dynamic colored light. Physical manipulation of the bottles -- opening and closing -- is the primary mode of interaction for controlling their musical contents. The bottles illustrates Mark Weiser's vision of the transparent (or invisible) interface that weaves itself into the fabric of everyday life. The bottles also exploits the emotional aspects of glass bottles that are tangible and visual, and evoke the smell of perfume and the taste of exotic beverages. This paper describes the design goals of the bottle interface, the arrangement of musical content, the implementation of the wireless electromagnetic tag technology, and the feedback from users who have played with the system.

This paper offers an initial analysis of economic and market issues in the development and deployment of mobile remote physiological monitoring services for medical patients through wireless wearable sensors and actuators. Examining the characteristics of the service technologies and related industries, this study focuses on the structure, participants and roles of standardisation of the layers within the emerging mobile remote physiological monitoring industry. The study concludes that the structure of the emerging mobile remote physiological monitoring industry will be oriented about service provision, be integrated with other personal / patient data storage services and be heavily influenced by the interplay of technological developments, the health market structure, existing players and regulation. Additionally, the keys players are likely to be the system integrators and service providers concentrating on large institutional customers. A focus of the paper is analysing both the causes and implications of a modular, horizontally layered industry structure likely to result from the mix of technologies, suppliers and customers as this market develops. The paper discusses why, although horizontal specialisation is the most likely outcome, there is little risk of key layers becoming commoditised. The paper also discusses the appropriate types and levels of standardisation and equipment certification activities that should be encouraged, along with from which groups and industries the pressure for these will come.

A band-pass delta-sigma modulator (BPDSM) is a key building block to implement a digital intermediate frequency (IF) receiver in a wireless communication system. This paper proposes a time-interleaved (TI) switched-capacitor (SC) BPDSM architecture that consists of 5-stage TI blocks with recursive loop. The proposed TI BPDSM provides reduction in the clock frequency requirement by a factor of 5 and relaxes the settling time requirement to one-fourth of conventional approach. The test chip was designed and fabricated for a 30-MHz IF system with a 0.35-µm CMOS process. The measured peak SNR for a 200-kHz bandwidth is 63 dB while dissipating 75 mW from a 3.3-V supply and occupying 1.3 mm2.

Classical models of speech recognition assume that a detailed, short-term analysis of the acoustic signal is essential for accurately decoding the speech signal and that this decoding process is rooted in the phonetic segment. This paper presents an alternative view, one in which the time scales required to accurately describe and model spoken language are both shorter and longer than the phonetic segment, and are inherently wedded to the syllable. The syllable reflects a singular property of the acoustic signal -- the modulation spectrum -- which provides a principled, quantitative framework to describe the process by which the listener proceeds from sound to meaning. The ability to understand spoken language (i.e., intelligibility) vitally depends on the integrity of the modulation spectrum within the core range of the syllable (3-10 Hz) and reflects the variation in syllable emphasis associated with the concept of prosodic prominence ("accent"). A model of spoken language is described in which the prosodic properties of the speech signal are embedded in the temporal dynamics associated with the syllable, a unit serving as the organizational interface among the various tiers of linguistic representation.

In this paper, general definitions of collusion secure codes are shown. Previously defined codes such as frameproof code, secure frameproof code, identifiable parent property code, totally c-secure code, traceability code, and (c,g/s)-secure code are redefined under various marking assumptions which are suitable for most of the fingerprinting systems. Then, new relationships among the combined notions of codes and the marking assumptions are revealed. Some (non)existence results are also shown.

The bit error rate (BER) performance of a fast frequency-hopped frequency division multiple access (FH-FDMA) system is evaluated with diversity combining receivers. The clipper receiver and the normalized envelope detection (NED) receiver which show better performance than other diversity combining receivers under n = 1 band multitone interference (MTI) are chosen as combining alternatives. From simulation results, n = 1 band MTI is the most destructive multitone interference strategy for the FH-FDMA system. As the number of groups increases, eventually becoming a FHMA system, the worst case performance of FH-FDMA with the clipper receiver improves monotonically, while that of the NED receiver hardly improves when the effect of the interference is relatively large. From the viewpoint of BER performance, the FHMA system with the clipper receiver is the most effective solution among the FH-FDMA systems in the presence of the worst case band MTI.

We demonstrate a simple BER monitoring method for WDM signals. Newly developed 32-channel wavelength selector based on thermo-optic switch and AWG is used. The BER of each channel is estimated from opened eye-diagrams obtained by asynchronous sampling. Good BER monitoring performance is confirmed.

This paper discusses performance issues for a sensor network. It describes the unique features of the sensor network and discusses studies on its protocols. Performance measures for the sensor network are investigated and studies related to them are surveyed. As an example of performance measures, this paper analyzes a sensor network's availability, which is the probability that all the sensor nodes are working without any of them having run out of energy. An explicit formula for the sensor network availability is derived, and the optimal placement of sensor nodes is investigated.

Indium tin oxide (ITO) films were deposited at a temperature below 50 by a low-voltage sputtering system. The sputtering voltage was fixed at 100 V and Ar, Kr, and Xe were used as the sputtering gases. Compared with the sputtering in Ar gas, the sputtering in Kr or Xe gas caused a significant suppression of crystallization of the deposited film and resulted in the formation of amorphous films. These films had much lower resistivities than the films deposited using Ar gas, since the Hall mobility of the films had a larger value. Typical Hall mobility and carrier density are 50 cm2/Vsec, and 51020 cm-3, respectively. This improvement was attributable to the reduction of high-energy particle bombardment to the film surface in the sputtering. These films are stable at a temperature below 150, and crystallization occurs at a temperature above 150.

In this paper, a new full on-chip high efficiency DC-DC voltage up converter with no inductance element is presented with power efficiency more than 74%. A method in the charge pump is described to have a regulated 3.3 V from 1.5 V for output power 4 mW. For medium power class, 100-200 mW, a boost converter is designed with on-chip inductor for 1.5 V to 3.3 V conversion. A buck converter is also designed for 3.3 V to 1 V conversion with power efficiency 72%. Inductor property of bond-wire is employed in the on-chip inductors. Analysis of efficiency relations and simulation results are presented for 0.35 µm CMOS technology.

A switched capacitor DC-DC voltage converter that has an arbitrary conversion ratio of rational number is presented. A given voltage conversion ratio is systematically expanded to construct a switched capacitor circuit that operates with a two-phase switching clock. The conversion ratio is completely free from capacitance values and ratios under the assumption that there is no charge transfer between the two switching phases. This means that the converter cannot supply any power to the load. This restricts the application of the converters to a very limited area such as a voltage reference generator that only provides a reference voltage and no power to a circuit. The conditions for the convergence of the output voltage and the stray capacitor effects are discussed. The output voltage error and required switching frequency are also discussed when the converter is used as a DC voltage supply source that provides power to a load.

A novel audio watermarking based on wavelet modulation is presented. The watermark signals are constructed by M-band wavelet modulation that can increase redundancy to improve the detection performance. In order to maximize the watermarking strength within the perceptual constraints, the watermark signals synthesized from different subbands are separately masked using a frequency auditory model. CDMA technique is implemented to achieve watermarking capacity. Experimental results show that this method is very robust.

By adding an auxiliary transformer to a single-stage single-switch power-factor-corrected converter (S4PFCC), the storage capacitor voltage and its range of voltage change against line voltage change are reduced. In addition, this transformer provides a direct power transfer path for input line to output load to increase the conversion efficiency. High power factor is maintained due to the elimination of dead angle of the input current. This paper presents detailed analysis and optimal design of a discontinuous conduction mode (DCM) boost-flyback S4PFCC with the auxiliary transformer. Experimental results for a 15 V/60 W prototype and with comparison to a S4PFCC without the auxiliary transformer are given to show the proposed approach effective.

Delta-sigma modulators (DSMs) are commonly use in high-resolution analog-to-digital converters, and band-pass delta-sigma modulators have recently been used to convert IF signals into digital signals. In particular, a quadrature band-pass delta-sigma modulator can achieve a lower total order, higher signal-to-noise ratio (SNR), and higher bandwidth when compared with conventional band-pass modulators. The current paper proposes a second-order three-bit quadrature band-pass delta-sigma modulator that can achieve a lower power consumption and better performance with a similar die size to a conventional fourth-order quadrature band-pass delta-sigma modulator (QBPDSM). The proposed system is integrated using CMOS 0.35 µm, double-poly, four-metal technology. The system operates at 13 MHz and can digitize a 200 kHz bandwidth signal centered at 4.875 MHz with an SNR of 85 dB. The power consumption is 35 mW at 3.3 V and 38 mW at 5 V, and the die size is 21.9 mm2.