This paper proposes a new algorithm named WGF (Weight-Gap First) scheduling. It not only supports the maximum throughput of a cell, but also provides the fairness of a terminal in HDR. The WG-based new scheduling algorithm is determined by served data of mobile terminals to guarantee requested data rate. WGs are renewed at each timeslot to improve throughput and fairness. Simulations confirm the better performance of the proposed algorithm in terms of throughput and fairness.

This paper describes an effective model which reproduces the dependence on the source/drain (S/D) process of the reverse short channel effect (RSCE) of the MOSFET threshold voltage (Vth). It is useful for local modeling which is effective within the limited process conditions. The proposed model is based on the physics where the key factor of RSCE is the dopant pile-up in the Si/SiO2 interface. The purpose of the model is for TCAD to be put to actual use as a quick solution tool. The calculation cost is much lower than a pair diffusion model, because the model is implemented in a conventional process simulator that solves one equation for each impurity. The capability of the simplified model is investigated for the dependence of various process conditions on the RSCE. Using our model, we also report the application of both the actual n-channel and p-channel MOSFETs.

A broadband RF front-end having a direct conversion architecture has been developed. The RF front-end consists of two broadband quadrature mixers, a multi-band local oscillator, and a broadband low-noise variable gain amplifier (LNVGA). The mixer achieves broadband characteristics through the incorporation of an in-phase power divider and a 45-degree power divider. The in-phase power divider achieves broadband characteristics through the addition of a compensation capacitor. The 45-degree power divider achieves broadband phase characteristics through the addition of a compensation capacitor and a compensation resistor. The local oscillator, which is composed of two VCOs, two frequency dividers, and four switches, can cover three systems including one FDD system. The LNVGA achieves its broadband characteristics without the use of reactance elements, such as inductors or capacitors. In a trial demonstration, when the RF frequency was between 900 MHz and 2.5 GHz, the mixer for a demodulator experimentally demonstrated an amplitude balance of less than 1.6 dB and a quadrature phase error of less than 3 degrees. When the RF frequency was between 900 MHz and 2.5 GHz, the mixer for a modulator demonstrated an image ratio of less than -30 dBc. The local oscillator demonstrated multi-band characteristics, which are able to cover the target frequencies for three systems (PDC, PHS, 2.4 GHz WLAN). From 900 MHz to 2.5 GHz, the amplifier shows a noise figure of less than 2.1 dB and a gain of 28 1.6 dB.

In several researches in recent years, it is shown that the circuit of a higher clock frequency can be obtained by controlling the clock-input timing of each register. However, the power consumption of the clock-tree obtained by them tends to be larger since the locations of registers are not well taken into account in clock scheduling. In this paper, we propose a novel clock tree synthesis that attains both the higher clock frequency and the lower power consumption. Our proposed algorithm determines the clock-input timings of registers step by step in constructing a clock tree structure. First, the clock period of a circuit is improved by controlling the clock-input timing of each register, and second, the clock-input timings are modified to construct a low power clock tree without deteriorating the obtained clock period. According to our experiments using several benchmark circuits, the power consumption of our clock trees attain about 9.5% smaller than previous methods.

We present pipelined simple matching, called PSM, for an input buffered switch to relax the scheduling timing constraint by modifying pipelined maximal-sized matching (PMM). Like the pipelined manner of PMM, to produce the matching results in every time slot, PSM employs multiple subschedulers which take more than one time slot to complete matching. Using only head-of-line information of input buffers, PSM successively sends each request to all subschedulers to provide a better matching opportunity. To obtain better performance, PSM uses unique starting points of scheduling pointers in which the difference between the starting points is equal for any two adjacent subschedulers for a same output. Using computer simulations under a uniform traffic, we show PSM is more appropriate than PMM for pipelined scheduling of an input buffered switch.

Advances in broadcast digitization have been rapid in Japan since the broadcasting satellite (BS) digital broadcast services commenced in December 2000. It requires that the receiver, which may also be connected to appliances using a Home Network, has an inbuilt HDD for storing interesting programs. However, it is difficult to guarantee QoS level on a Home Network composed of heterogeneous sub-networks. Therefore, for the purpose of an efficient and appropriate transmission of a video stream, such as MPEG over the Home Network, a new scalable MPEG transmission method is required. For this we propose a Scalability method allowing for Impairments Propagation (SIP), which takes into account the impairments propagated to other frames due to the loss of a macroblock in a given frame. In this paper, we introduce the SIP technique, analyze it mathematically, and evaluate its performance.

This paper presents a method of extracting car license plates captured from the arbitrary directions by using symmetry features. The generalized symmetry transform (GST) produces continuous features of symmetry between two points by combining locality constraint and reflectional symmetry, but its time complexity of GST is increased by the second power of the radius of a searching window. To achieve considerable reduction of this time complexity, we propose a scan line based GST (SLGST) which calculates the symmetry between a pair of edge pixels along the scan lines. Instead of calculating the global symmetry of a license plate, we assign the symmetry contribution acquired from SLGST to the corner point estimated from two edge points and their gradient orientations. The right angle tuned SLGST (RATSLGST) is newly proposed to detect the right angle corners more effectively. Image normalization by image warping is adopted to make such segmentation of license plate and later identification much easier. We also adopt the verifier that evaluates a candidate license plate to enhance extraction rate. Our experiments show that the proposed method for extracting perspectively distorted license plates is fairly reliable.

Fiber-optic access system integration is the key to providing various kinds of services to home users. The combination of ATM- and SCM-PON systems is essential to support a high-speed data service and analog/digital video distribution services. From this viewpoint, a frequency-division- multiplexing technique for digital baseband and subcarrier multiplexed signals is required to achieve system integration. However, system integration for these two access systems has not been fully investigated yet. The SCM-PON system, which uses a super wideband optical FM converter, will enable these two different kinds of access system (ATM and SCM) to be integrated. In this paper, we describe experimentally obtained results for frequency- division-multiplexed signals consisting of digital baseband and subcarrier- multiplexed signals. The experiments were carried out using a 622-Mb/s baseband signal and an FM-converted signal containing AM and 64QAM signals. The experimental results reveal that the inter-channel interference between the digital baseband and FM-converted signals restricts the number of subcarriers for AM and 64QAM. With an intermediate frequency of 3 GHz for the FM-converted signal, an FDM signal consisting of 622-Mb/s baseband, 30 carriers of 64QAM, and 11 carriers of AM was successfully transmitted.

Intelligent transport systems (ITS) are promising systems to give excellent solutions for many problems that we face in transport today. Not only road-to-vehicle communications but also inter-vehicle communications in ITS are expected to become popular in the future. On the other hand, an intra-vehicle communication network should be supported by multimedia information according to the explosive expansion of the Internet use and the like. An inexpensive transmission medium and transceiver becomes indispensable in such in-vehicle local area network (LAN) for multimedia information as these must handle full-motion video signals, without any electromagnetic interference. We have proposed on-board network architecture based on optical P1394b to realize effective inter-vehicle communications and enable all equipment which freely add and remove to the intra-vehicle network. And according to the proposed architecture, we have developed a 500-Mbit/s low-cost optical transceiver for the intra- and inter-vehicle communication network using a commercially available plastic clad fiber. An LD for the compact disk drive and a large area photodiode were adopted as low-cost and high-speed optical devices, and a logic direct driving type simple circuit having temperature compensation function was developed. Simple assembly technologies such as plastic molding and optical element press-fitting were also developed for mounting to reduce assembly cost. The total cost of the fabricated optical transceiver can be reduced less than 2/3, comparing with that of conventional one. We have performed transmission experiments and vibration tests using our optical transceivers that are mounted in on-board elements and connected to the on-board network, and have confirmed these stable operations. Experimental results show our proposed architecture and fabricated optical transceiver can play a key role in the intra- and inter-vehicle communication network.

This paper presents circuit models for the description of the frequency-dependent behavior of coils for horizontal deflection in CRTs. This enables CRT circuit designers to use circuit simulation programs to predict the high-frequency behavior of the interaction between the deflection coils and the drive circuit. An overview is given of the major phenomena that occur in CRT deflection coils at various frequencies. Models are presented for the dissipative, the capacitive, and the resonant behavior in successive frequency intervals. With these models, phenomena such as power dissipation and ringing can not only be related to design parameters, but can also be calculated from impedance characteristics which are relatively easy to measure.

In this paper, we propose a new job scheduling method for distributed parallel systems that can simultaneously achieve two main goals of the job scheduling in those systems: to minimize the execution time of a parallel job without disturbing the execution of the other jobs. We try to achieve those goals by introducing a new scheduler, called active scheduler, that dynamically controls the priority of parallel programs and balances the workload of host computers depending on the status of the underlying runtime environment. We implemented a prototype system of the scheduler to evaluate its effectiveness. The result of experiments implies that the overhead of introducing the active scheduler is at most 15% of the original execution time, and it is in fact effective to adjust the execution of parallel programs to an actual distributed environment in which many users execute their jobs simultaneously.

Electroluminescence (EL) under alternating-current (ac) operation is first reported for n+-polysilicon/SiO2/p-Si MOS capacitors with 50 nm Si-implanted SiO2. Visible EL can be observed with the naked eye in the dark. The ac operation by pulse-wave distinctly enhances the EL intensity and its lifetime. The pulse frequency affects the EL spectrum and thus the EL color. A model of EL mechanism is proposed for the Si-implanted MOS EL device, which has a possibility of visible light emitting device.

Thin-film electroluminescent (TFEL) devices have been newly developed using Y2GeO5 oxide phosphor thin films prepared by r.f. magnetron sputtering. Multicolor emissions were observed in TFEL devices fabricated using various impurity-activated Y2GeO5 phosphor thin films. A high-luminance TFEL device was fabricated using a Y2GeO5:Mn thin film prepared with a Mn content of 2 at.% and postannealed at 1020: luminances of 414 and 3020 cd/m2 and luminous efficiencies of 6.7 and 0.93 lm/W for yellow emission when driven at 60 Hz and 1 kHz, respectively. Newly developed oxide Y2GeO5:Mn phosphors are very promising for use as the thin-film emitting layer of TFEL devices.

A novel adaptive technique based on a statistical model by estimating window size for unsupervised segmentation of a set of MR images is presented. The window size estimation is achieved in the image using a MDL for mixture estimation and segmentation, and allows the technique to well reflect local characteristics of the image.

Autonomous distributed manufacturing systems (ADMS) consist of multiple intelligent components with each component acting according to its own judgments. The ADMS objective is to realize more agile and adaptive manufacturing systems. This paper presents the introduction of context-dependent agents (CDAs) in ADMS that switch strategies depending on system conditions to achieve better performance than can be realized by agents that use the same strategies under all system conditions. For the real-time job scheduling problem, the paper presents a basic CDA architecture and the results of an extensive empirical evaluation of its performance relative to other rule-based schemes based on several common indices for real-time dispatch.

Today, many audiovisual delivery systems, including video streaming and video conferencing, are being developed for use over a range of networking technologies, the differing characteristics of which pose problems for service level interoperability. Multimedia transcoding is one means to provide interoperability between different types of audiovisual terminals and between terminals that connect to different networks. In this paper, we will present a multimedia transcoder system, which provides interoperability between video conferencing terminals on IP networks and mobile terminals on mobile networks.

In this paper, we present the theoretical analysis of the bit error rate (BER) performance of Single-Carrier Modulation (SCM) and Orthogonal Frequency Division Multiplexing (OFDM) systems under two types of temporally localized man-made noises (generalized shot noise and bursty noise models) environments. The robustness of OFDM system against these two kinds of man-made noises is discussed and then compared with that of SCM system at the same transmission rate. We show that for OFDM system, the BER performance highly depends on the number of subcarriers and the strength of the man-made noise, i.e., the level of the power spectral density of the man-made noise. In addition to the common knowledge on OFDM, we show that OFDM system is sometime less robust to the man-made noises than SCM system.

The electromagnetic wave scattering from ocean-like lossy dielectric random rough surfaces is numerically analyzed by using FVTD method. We have investigated the problem of low-grazing-angle (LGA) scattering in order to gain a better understanding of experimental data for the microwave backscattering from ocean-like surfaces. It is indicated that the FVTD results are in good agreement with the experimental data.

An n-detection testing for stuck-at faults can be used not only for delay fault testing but also for detection of unmodeled faults. We have developed a hybrid BIST circuit; that is, a method consisting of a shift register with partial rotation and a procedure that selects test vectors from ATPG ones. This testing method can perform at-speed testing with high stuck-at fault coverage. During the at-speed testing, a subset of the ATPG vectors is input by using a low-speed tester. Computer simulations on ISCAS'85, ISCAS'89, and ITC'99 circuits are conducted for n = 1, 2, 3, 5, 10, and 15. The simulation results show that the amount of test vectors can be reduced to ranging from 52.3% to 0.9% in comparison with that of the ATPG vectors. As a result, the proposed method can reduce the cost of at-speed testing.

Recently, demand for multimedia service applicable with wireless ad hoc networks is increasing. Many protocols which support QoS (Quality of Service) defined by ITU H.323 are suitable for the system with a central coordinator (ex. access point), and are not applied to ad hoc networks. Since each mobile station sends a packet randomly in a wireless network, it is necessary to avoid a packet collision which results in the decrement of the channel throughput. IEEE 802.11 is a standard for wireless LANs. The basic access mechanism in its media access control (MAC) protocol is the distributed coordination function (DCF) based on carrier sense multiple access with collision avoidance (CSMA/CA). However, this mechanism does not have QoS control, and packet collision may occur frequently with the increase of the number of mobile stations. In this paper, the two queues, voice over IP (VoIP) queue and DATA queue, are set in each mobile station, and we propose a novel MAC protocol using multiple queues for QoS. Our scheme consists of carrier sensing, packet scheduling and collision avoidance, and improves the contention window in DCF. We use two kinds of packet scheduling. One is the scheduling in a mobile station, and the other is the scheduling among mobile stations. We called the proposed scheduling among mobile stations D2VTS (Distributed Double Virtual Time Scheduling). Simulations are conducted to analyze the proposed scheme. The simulation results show that our scheme is able to carry multimedia traffic with a higher performance compared with the conventional DCF.