In this paper, we propose the novel Dynamic Feedback (DF-) MCML technique for high-speed and high-gain MCML type latch. The concept of the proposed DF-MCML technique is as follows; the output node signal is feedbacked to the input node in Sampling-Mode, and the output node is opened from the input node in Holding-Mode. It is shown by analytic theory that by this dynamic feedback sequence, both stability and sensibility of latch in Sampling-Mode is exponentially improved, and the gain of latch in Holding-Mode is drastically increased. Finally, we have numerically investigated the circuit performance of the novel DF-MCML type latch in comparison with the conventional MCML type latch by using P-Spice simulator. The maximum operation frequency of 180 nm DF-MCML type latch reaches over 20 GHz that is 2 times than the conventional MCML type latch. It is made clear that the proposed novel Dynamic Feedback MCML technique is suitable for over 10 GHz high-speed and high-gain Si ULSIs.

This paper compares the turbo code and rate-compatible low-density parity-check (LDPC) codes based on the block error rate (BLER) performance and decoding complexity in order to clarify which channel coding scheme is most appropriate for the channel coding scheme in the OFDM based Evolved UTRA (E-UTRA) downlink. Simulation results and the decoding complexity analysis show that although the Rate-Compatible/Quasi-Cyclic (RC/QC)-LDPC code employing an offset layered belief propagation (BP) method can reduce the computational complexity by approximately 30% for the channel coding rate of R ≥ 1/2, the required average received signal energy per bit-to-noise power spectrum density ratio (Eb/N0) is degraded by approximately 0.2-0.3 dB for R = 1/3, 1/2 and 3/4 compared to that for the turbo code. Moreover, the decoding complexity level of the RC/QC-LDPC code with the δ-min algorithm is almost the same or higher than that for the turbo code with a slight degradation in the required received Eb/N0. Although the decoding complexity level of the ZigZag code is lower than that of the turbo code, the code brings about a distinct loss in the required average received Eb/N0 of approximately 0.4 dB. Finally, the turbo Single Parity Check (SPC) code improves the BLER performance compared to the ZigZag code, i.e., achieves almost the same BLER performance as that for the turbo code, at the cost of a two-fold increase in the decoding complexity. As a result, we conclude that the turbo code with a contention free interleaver is more promising than the LDPC codes for prioritizing the achievable performance over complexity and as the channel coding scheme for the shared data channel in the E-UTRA.

We propose an appearance manifold with view-dependent covariance matrix for face recognition from video sequences in two learning frameworks: the supervised-learning and the incremental unsupervised-learning. The advantages of this method are, first, the appearance manifold with view-dependent covariance matrix model is robust to pose changes and is also noise invariant, since the embedded covariance matrices are calculated based on their poses in order to learn the samples' distributions along the manifold. Moreover, the proposed incremental unsupervised-learning framework is more realistic for real-world face recognition applications. It is obvious that it is difficult to collect large amounts of face sequences under complete poses (from left sideview to right sideview) for training. Here, an incremental unsupervised-learning framework allows us to train the system with the available initial sequences, and later update the system's knowledge incrementally every time an unlabelled sequence is input. In addition, we also integrate the appearance manifold with view-dependent covariance matrix model with a pose estimation system for improving the classification accuracy and easily detecting sequences with overlapped poses for merging process in the incremental unsupervised-learning framework. The experimental results showed that, in both frameworks, the proposed appearance manifold with view-dependent covariance matrix method could recognize faces from video sequences accurately.

In this paper, an information distribution model based on human's behavior is proposed. We also propose dynamic parameters to make the model more practical for real life social network. Subsequently, the simulations are conducted based on the small-world network and its characteristics, and the parameters in the model are analyzed to increase efficiently the power of information distribution. Our study and simulation results show that the proposed model can be used to analyze and predict the effectiveness of information distribution. Moreover, the study also shows how to use the model parameters to increase power of the distribution.

In this letter, we propose a novel signal detection method, reduced complexity QRM-MLD, which achieves almost identical error performance to that of the conventional QRM-MLD while significantly reducing the computational complexity.

For recent and future nanometer-technology VLSIs, static and dynamic delay variations become a serious problem. In many cases, the hold constraint, as well as the setup constraint, becomes critical for latching a correct signal under delay variations. This paper treats the hold constraint in a datapath circuit, and discusses a register assignment in high level synthesis considering delay variations. Our approach to ensure the hold constraint under delay variations is to enlarge the minimum-path delay between registers, which is called minimum-path delay compensation (MDC) in this paper. MDC can be done by inserting delay elements mainly in non-critical paths of a functional unit (FU). One of our contributions is to show that the minimization of the number of minimum-path delay compensated FUs is NP-hard in general, and it is in the class P if the number of FUs is a constant. A polynomial time algorithm for the latter is also shown in this paper. In addition, an integer linear programming (ILP) formulation is also presented. The proposed method generates a datapath having (1) robustness against delay variations, which is ensured partly by MDC technique and partly by SRV-based register assignment, and (2) the minimum possible numbers of MDCs and registers.

It is known that MIMO channel matrix condition number influences detectors performance. Several authors have proposed combined decoders, mainly suboptimal, to cope with this fact. These combined algorithms require an estimation of the MIMO channel matrix condition number and a selection of a suitable threshold condition number. This letter presents practical algorithms to carry out the referred tasks and shows their performance in practice.

In this letter, we propose a computationally efficient search space for QRM-MLD that is used for spatially multiplexed multiple antenna systems. We perform a set of computer simulations to show that the proposed method achieves a performance that is near to that of the original QRM-MLD, while its computational complexity is near to that of rank-QRM-MLD.

A sound field reproduction method is proposed that uses blind source separation and a head-related transfer function. In the proposed system, multichannel acoustic signals captured at distant microphones are decomposed to a set of location/signal pairs of virtual sound sources based on frequency-domain independent component analysis. After estimating the locations and the signals of the virtual sources by convolving the controlled acoustic transfer functions with each signal, the spatial sound is constructed at the selected point. In experiments, a sound field made by six sound sources is captured using 48 distant microphones and decomposed into sets of virtual sound sources. Since subjective evaluation shows no significant difference between natural and reconstructed sound when six virtual sources and are used, the effectiveness of the decomposing algorithm as well as the virtual source representation are confirmed.

This work presents a full-chip RLC crosstalk budgeting routing flow to generate a high-quality routing design under stringent crosstalk constraints. Based on the cost function addressing the sensitive nets in visited global cells for each net, global routing can lower routing congestion as well as coupling effect. Crosstalk-driven track routing minimizes capacitive coupling effects and decreases inductive coupling effects by avoiding placing sensitive nets on adjacent tracks. To achieve inductive crosstalk budgeting optimization, the shield insertion problem can be solved with a minimum column covering algorithm which is undertaken following track routing to process nets with an excess of inductive crosstalk. The proposed routing flow method can identify the required number of shields more accurately, and process more complex routing problems than the linear programming (LP) methods. Results of this study demonstrate that the proposed approach can effectively and quickly lower inductive crosstalk by up to one-third.

In this paper, we introduce layered low-density generator matrix (Layered-LDGM) codes for super high definition (SHD) scalable video systems. The layered-LDGM codes maintain the correspondence relationship of each layer from the encoder side to the decoder side. This resulting structure supports partial decoding. Furthermore, the proposed layered-LDGM codes create highly efficient forward error correcting (FEC) data by considering the relationship between each scalable component. Therefore, the proposed layered-LDGM codes raise the probability of restoring the important components. Simulations show that the proposed layered-LDGM codes offer better error resiliency than the existing method which creates FEC data for each scalable component independently. The proposed layered-LDGM codes support partial decoding and raise the probability of restoring the base component. These characteristics are very suitable for scalable video coding systems.

An AuSn reflow process using hydrogen radicals as a way to avert the cleaning of flux residues was investigated for its application to solder bumping. AuSn particles (manufactured by a gas atomizer) smaller than 5 µm, which are difficult to reflow by conventional methods that use rosin mildly activated (RMA) flux, were used for the experiments. In this process, the reduction effect by the hydrogen radicals removes the surface oxides of the AuSn particles. Excellent wetting between 1-µm-diameter AuSn particles and Ni metallization occurred in hydrogen plasma. Using hydrogen radicals, 100 µm-diameter AuSn bumps without voids were successfully formed at a peak temperature of 300. The average bump shear strength was approximately 73 gf/bump. Bump inspection after shear testing showed that a fracture had occurred between the Au/Ni/Cr under bump metallurgy (UBM) and Si substrate, suggesting sufficient wetting between the AuSn bump and the UBM.

This letter proposes an adaptive threshold control algorithm for a low complex noncoherent IR-UWB receiver using a 1-bit ADC. To estimate and control a threshold level in the noncoherent IR-UWB receiver, it uses binary output of the 1-bit ADC instead of energy level of received signals using a high resolution ADC, which reduces hardware complexity of the receiver. Theoretical performance evaluation and computer simulation demonstrates that the performance of the proposed algorithm is similar to that of theoretically optimum one.

The performance of an analog winner-take-all (WTA) circuit is affected by the corner error and the offset error. Despite the fact that the corner error can be reduced with large transconductance of the transistor, the offset error caused by device mismatch has not been completely studied. This paper presents the complete offset error analysis, and proposes low offset design guidelines and an offset cancellation scheme. The experimental results show good agreement with the theoretical analysis and the drastic improvement of the offset error.

This letter proposes a new transceiver for OFDM systems based on Smooth Local Trigonometric Transform (LTT). In our transceiver, the transmitter is realized by first modulating the original serial data using a constellation mapper, then feeding the results into the inverse LTT modulator. Unlike the conventional DFT-OFDM system, which always uses the roll cosine function as its window function, the proposed system needs no additional window function for the reason that LTT transform includes a bell-shaped window function by itself. Moreover, each LTT-OFDM symbol has a much more rapid attenuation rate outside of the spectral bandwidth and better spectrum convergence. In the receiver, the original data is recovered by demodulating the received data using forward LTT. Comparative simulation results from the conventional DFT-OFDM system, the system we proposed, and the recently proposed DCT based OFDM system are discussed in terms of bit error rate (BER).

We present a novel model, named Category Constraint-Latent Dirichlet Allocation (CC-LDA), to learn and recognize natural scene category. Previous work had to resort to additional classifier after obtaining image topic representation. Our model puts the category information in topic inference, so every category is represented in a different topics simplex and topic size, which is consistent with human cognitive habit. The significant feature in our model is that it can do discrimination without combined additional classifier, during the same time of getting topic representation. We investigate the classification performance with variable scene category tasks. The experiments have demonstrated that our learning model can get better performance with less training data.

This paper presents implementation techniques of fast Ate pairing of embedding degree 12. In this case, we have no trouble in finding a prime order pairing friendly curve E such as the Barreto-Naehrig curve y2=x3+a, a∈Fp. For the curve, an isomorphic substitution from G2 ⊂ E(Fp12 into G'2 in subfield-twisted elliptic curve E'(Fp2) speeds up scalar multiplications over G2 and wipes out denominator calculations in Miller's algorithm. This paper mainly provides about 30% improvement of the Miller's algorithm calculation using proper subfield arithmetic operations. Moreover, we also provide the efficient parameter settings of the BN curves. When p is a 254-bit prime, the embedding degree is 12, and the processor is Pentium4 (3.6 GHz), it is shown that the proposed algorithm computes Ate pairing in 13.3 milli-seconds including final exponentiation.

We fabricated high-power pure blue laser diodes (LDs) by using GaN-based material for full-color laser display. The operating output power, voltage and wall-plug efficiency of the LDs at forward current of 1.0 A were 1.17 W, 4.81 V and 24.3%, respectively. The estimated lifetime of the LDs was over 30,000 hours under continuous-wave operation.

A threshold-logic gate device consisting of subthreshold MOSFET circuits is proposed. The gate device performs threshold-logic operation, using the technique of current-mode addition and subtraction. Sample digital subsystems, i.e., adders and morphological operation cells based on threshold logic, are designed using the gate devices, and their operations are confirmed by computer simulation. The device has a simple structure and operates at low power dissipation, so it is suitable for constructing cell-based, parallel processing LSIs such as cellular-automaton and neural-network LSIs.

Multi-carrier code division multiple access (MC-CDMA) is a promising wireless access technique for the next generation mobile communications systems, in which broadband packet data services will dominate. Hybrid automatic repeat request (HARQ) is an indispensable error control technique for high quality packet data transmission. The HARQ throughput performance of multi-code MC-CDMA degrades due to the presence of residual inter-code interference (ICI) after frequency-domain equalization (FDE). To reduce the residual ICI and improve the throughput performance, a frequency-domain soft interference cancellation (FDSIC) technique can be applied. An important issue is the generation of accurate residual ICI replica for FDSIC. In this paper, low-density parity-check coded (LDPC-coded) MC-CDMA HARQ is considered. We generate the residual ICI replica from a-posteriori log-likelihood ratio (LLR) of LDPC decoder output and evaluate, by computer simulation, the throughput performance in a frequency-selective Rayleigh fading channel. We show that if the residual ICI is removed, MC-CDMA can provide a throughput performance superior to orthogonal frequency division multiplexing (OFDM).