This paper describes a new technique for the design of 3-terminal regulators in which the output voltage level can be adjusted without additional terminals or extra off-chip components. This circuit restricts the increase in the number of terminal pins by using a pin as both a voltage supply output and a voltage setup input. The voltage setup information is introduced using a serial control signal from outside the chip. Using the intermediate voltage level between the supply voltage and the regulator output, the adjustment data in the internal nonvolatile memory are safely updated without noise disturbance. To input the setup information into the chip in a stable manner, we developed a new 1-wire serial interface which combines key pattern matching and burst signal detection. To ensure high reliability, we suggested a quantitative method for evaluating the influence of noise in our new interface using a simple model with superimposed random noise. Circuits additional to those for a conventional 3-terminal regulator, include a 1-wire serial communication circuit, a low-capacity non-volatile memory, and a digital to analog (D/A) converter. A test chip was developed using 0.35 µm standard CMOS process, and there was almost no overhead to the conventional 3-terminal regulator in both chip area and power dissipation. In an on-board test with the test chip, we confirmed successful output voltage adjustment from 1.0 V to 2.7 V with approximately 6.5 mV precision.

This paper presents a simplifying method of the two previous fault attacks to pairing and the Miller algorithms based on a practical fault assumption. Our experimental result shows that the assumption is feasible and easy to implement.

Source-follower-based (SFB) continuous-time low-pass filters (LPF) have the advantages of low power and high linearity over other filter topologies. The second-order SFB filter cells, which are key building blocks for high-order SFB filters, are often realized by composite source follower with positive feedback. For a single branch 2nd-order SFB cell, the linearity drops severely at high frequencies in the pass band because its slew-rate is restricted by the Q factor and the pole frequency. The folded 2nd-order SFB cell provides higher linearity because it has two DC branches, and hence has another freedom to increase the slew rate. However, because of the positive feedback, the folded and unfolded 2nd-order SFB cells, especially those with high Q factors, tend to be unstable and act as relaxation oscillators under given circuit parameters. In order to obtain higher Q factor, a new topology for the 2nd-order SFB cell without positive feedback is proposed in this paper, which is unconditionally stable and can provide high linearity. Based on the folded 2nd-order SFB cell and the proposed high-Q SFB cell, a 264 MHz sixth-order LPF with 3 stages for ultra wideband (UWB) applications is designed in 0.18 µm CMOS technology. Simulation results show that the LPF achieves an IIP3 of above 12.5 dBm in the whole pass band. The LPF consumes only 4.1 mA from a 1.8 V power supply, and has a layout area of 200 µm 150 µm.

Most document clustering methods are a challenging issue for improving clustering performance. Document clustering based on semantic features is highly efficient. However, the method sometimes did not successfully cluster some documents, such as highly articulated documents. In order to improve the clustering success of complex documents using semantic features, this paper proposes a document clustering method that uses terms of the condensing document clusters and fuzzy association to efficiently cluster specific documents into meaningful topics based on the document set. The proposed method improves the quality of document clustering because it can extract documents from the perspective of the terms of the cluster topics using semantic features and synonyms, which can also better represent the inherent structure of the document in connection with the document cluster topics. The experimental results demonstrate that the proposed method can achieve better document clustering performance than other methods.

In this letter, we propose a new resource allocation scheme for a two-way OFDM relay network with fairness constraints. To maximize sum capacity, subcarriers and their power are successively allocated to the relays based on channel conditions. Also, the power constraint is imposed on each relay to achieve fairness for the relays. Simulation results show that the proposed scheme improves sum capacity and fairness significantly.

Fair exchange is an important tool to achieve “fairness” of electronic commerce. Several previous schemes satisfy universally composable security which provides security preserving property under complex networks like the Internet. In recent years, as the demand for electronic commerce increases, fair exchange for electronic vouchers (e.g., electronic tickets, moneys, etc.) to obtain services or contents is in the spotlight. The definition of fairness for electronic vouchers is different from that for general electronic items (e.g., the sender must not do duplicate use of exchanged electronic vouchers). However, although there are universally composable schemes for electronic items, there is no previous study for electronic vouchers. In this paper, we introduce a universally composable definition of fair voucher exchange, that is, an ideal functionality of fair voucher exchange. Also, we prove the equivalence between our universally composable definition and the conventional definition for electronic vouchers. Thus, our formulation of the ideal functionality is justified. Finally, we propose a new fair voucher exchange scheme from non-blocking atomic commitment as black-box, which satisfies our security definition and is adequate for mobile environments. By instantiating general building blocks with known practical ones, our scheme can be also practical because it is implemented without trusted third party in usual executions.

A new compact form of the sliding window recursive least squares (SWRLS) algorithm, the I-SWRLS algorithm, is derived using an indefinite matrix. The resultant algorithm has a form similar to that of the traditional recursive least squares (RLS) algorithm, and is more computationally efficient than the conventional SWRLS algorithm including two Riccati equations. Furthermore, a computationally reduced version of the I-SWRLS algorithm is developed utilizing a shift property of the correlation matrix of input data. The resulting fast algorithm reduces the computational complexity from O(N2) to O(N) per iteration when the filter length (tap number) is N, but retains the same tracking performance as the original algorithm. This fast algorithm is much easier to implement than the existing SWC FTF algorithms.

Locator/ID Separation Protocol (LISP) is an efficient proposal for solving the severe routing scalability problems existing in the current IPv4-based Internet and the future IPv6-based Internet. However, the basic LISP architecture does not specify how to support mobility in detail. As mobility is a fundamental issue faced by the future Internet, LISP mobility architecture (LISP-MN) was proposed recently to extend LISP to support mobility. Nevertheless, LISP-MN is a host-based mobility approach which requires software changes in end systems. To some extent, such a design breaks the primary design principles of LISP, which is a network-based protocol and requires no modification to the hosts. In addition, LISP-MN faces the same inherent problems as other host-based approaches (e.g., MIPv4, MIPv6), such as handover latency, packet loss, and signalling overhead. To solve the above problems, this paper proposes MobileID, which is a network-based localized mobility approach for LISP. In our design, a mobile node is not aware of its mobility and does not participate in handover signalling. Instead, the network takes the responsibility for managing mobility on behalf of the mobile node. We present a general overview of MobileID architecture, and introduce the detailed protocol operations in terms of the basic MobileID handover process and the route optimization procedures. Furthermore, we describe a MobileID analytic model, and compare MobileID handover performance with three representative mobility solutions, i.e., LISP-MN, MIPv6 and PMIPv6. Numerical results show the superior performance of MobileID. The handover latency of MobileID is much lower than those of LISP-MN and MIPv6, and it becomes lower than that of PMIPv6 in case of a long wireless link delay.

This paper gives statistical analysis of double fading channels which are typically found in keyhole MIMO(multiple input multiple output) models. First, to investigate the potential of identically distributed double Nakagami-Rice MIMO keyhole channels including LOS(line of sight) environment, the density function of SNR(signal to noise ratio) which corresponds to the only one non-zero eigenvalue of channel correlation matrix is presented. In addition to the exact expression with an infinite series form, an approximation formula with a simple monomial form derived by substituting Nakagami m formula for Rician distribution is also considered. Next, similar equations are introduced for double Rayleigh channels which have correlated branches in both the transmitter and receiver sides(independent but nonidentical case is included here). Through computer simulations, the effectiveness of the proposed formulae is verified, and in double Nakagami-Rice fading case, the advantage of the approximated formula particularly for large array size and/or large Rician factor is demonstrated.

Recent works on MIMO receiver design were mainly focused on sphere decoding, which provides a trade-off between the performance and complexity by suitably choosing the “radius” or the number of candidates in the search space. Meanwhile, another approach, called poly-diagonalization and trellis detection, has been proposed to compromise the complexity and performance. In this paper, we compare various MIMO receiver algorithms in terms of both performance and complexity. The performance is evaluated in a frequency selective fading channel environment on the basis of orthogonal frequency division multiplexing with channel coding, for which the generation of soft decision values is crucial. The simulations show that the poly-diagonalization approach matches the performance of sphere decoding at similar computational complexity.

In this paper, we propose a spatially adaptive gradient-projection algorithm for the H.264 video coding standard to remove coding artifacts using local statistics. A hybrid method combining a new weighted constrained least squares (WCLS) approach and the projection onto convex sets (POCS) approach is introduced, where weighting components are determined on the basis of the human visual system (HVS) and projection set is defined by the difference between adjacent pixels and the quantization index (QI). A new visual function is defined to determine the weighting matrices controlling the degree of global smoothness, and a projection set is used to obtain a solution satisfying local smoothing constraints, so that the coding artifacts such as blocking and ringing artifacts can be simultaneously removed. The experimental results show the capability and efficiency of the proposed algorithm.

Hop-timing detection is of extreme importance for the reception of frequency hopping (FH) signals. Any error in the hop-timing detection has a deleterious effect on the performance of the receiver in frequency hopping (FH) communication systems. However, it is not easy to detect the hop-timing under low signal to noise power ratio (SNR) environments. Adaptive array antennas (AAA) have been expected to improve the performance of FH communication systems by beamforming for the direction of arrival of the desired signal. Since the conventional AAA exploits at least the coarse synchronization for dehopping of FH signals before achieving the beamforming, any fault in the hop-timing detection causes the deterioration of the performance of AAA. Using AAA based on the constant modulus algorithm (CMA), this paper proposes a new method for blind beamforming and hop-timing detection for FH signals. The proposed method exploits both the spatial and temporal characteristics of the received signal to accomplish the beamforming and detect the hop-timing without knowing any a priori information such as fine/coarse time synchronization and training signal. The performance verifications of the proposed method based on pertinent simulations are presented.

This paper introduces an interactive expression editing system that allows users to design facial expressions easily. Currently, popular example-based methods construct face models based on the examples of target face. The shortcoming of these methods is that they cannot create expressions for novel faces: target faces not previously recorded in the database. We propose a solution to overcome this limitation. We present an interactive facial-geometric-feature animation system for generating expressions of novel faces. Our system is easy to use. By click-dragging control points on the target face, on the computer screen display, unique expressions are generated automatically. To guarantee natural animation results, our animation model employs prior knowledge based on various individuals' expressions. One model prior is learned from motion vector fields to guarantee effective facial motions. Another, different, model prior is learned from facial shape space to ensure the result has a real facial shape. Interactive animation problem is formulated in a maximum a posterior (MAP) framework to search for optimal results by combining the priors with user-defined constraints. We give an extension of the Motion Propagation (MP) algorithm to infer facial motions for novel target faces from a subset of the control points. Experimental results on different facial animations demonstrate the effectiveness of the proposed method. Moreover, one application of our system is exhibited in this paper, where users create expressions for facial sketches interactively.

The aggregate throughput of wireless mesh networks (WMNs) can be significantly improved by equipping the mesh routers with multiple radios tuned to orthogonal channels. Not only the links using orthogonal channels can be activated at a time, but some links in the same channel also can be activated concurrently if the Signal-to-Interference-and-Noise Ratio (SINR) at their receivers is not lower than the threshold, which is the spatial-reuse characteristic. STDMA is considered as one of the medium access schemes that can exploit spatial reuse to improve network throughput. Past studies have shown that optimizing the performance of STDMA is NP-Hard. Therefore, we propose a STDMA-based scheduling algorithm that operates in a greedy fashion for WMNs. We show that the proposed algorithm enhances not only the throughput but also the fairness by capturing the essence of spatial-reuse approach of STDMA and giving medium access opportunities to each network element based on its priority. We furthermore validate our algorithm through theoretical analysis and extensive simulations and the results show that our algorithm can outperform state-of-the-art alternatives.

The Network-on-Chip (NoC) is limited by the reliability constraint, which impels us to exploit the fault-tolerant routing. Generally, there are two main design objectives: tolerating more faults and achieving high network performance. To this end, we propose a new multiple-round dimension-order routing (NMR-DOR). Unlike existing solutions, besides the intermediate nodes inter virtual channels (VCs), some turn-legally intermediate nodes inside each VC are also utilized. Hence, more faults are tolerated by those new introduced intermediate nodes without adding extra VCs. Furthermore, unlike the previous solutions where some VCs are prioritized, the NMR-DOR provides a more flexible manner to evenly distribute packets among different VCs. With extensive simulations, we prove that the NMR-DOR maximally saves more than 90% unreachable node pairs blocked by faults in previous solutions, and significantly reduces the packet latency compared with existing solutions.

This paper shows a fast estimation method of very low error rate of low-density parity-check (LDPC) codes. No analytical tool is available to evaluate performance of LDPC codes, and the traditional Monte Carlo simulation methods can not estimate the low error rate of LDPC codes due to the limitation of time. To conquer this problem, we propose another simulation method which is based on the optimal simulation probability density function (PDF). The proposed simulation PDF can also avoid the dependency between the simulation time and the number of dominant trapping sets, which is the problem of some fast simulation methods based on the error event simulation method. Additionally, we show some numerical examples to demonstrate the effectiveness of the proposed method. The simulation time of the proposed method is reduced to almost less than 1/10 of that of Cole et al.'s method under the condition of the same accuracy of the estimator.

This paper discusses a dual-stage detection scheme composed of coarse detection stage and refined detection stage for the continuous detection operation of Ultra-Wideband (UWB) detect and avoid (DAA). The threshold factor for the probability of indefinite detection is first proposed and defined to combine the two stages. The proposed scheme focuses on the integration of two different detection schemes with different complexities in order to reduce total computational complexity. A Single-carrier Frequency Division Multiple Access (SC-FDMA) uplink system operating in a Time Division Duplex (TDD) mode is utilized to evaluate the proposed detection scheme. Simulation results indicate that the proposed scheme can make a tradeoff between the detection performance and the computational complexity by setting the probability of indefinite detection.

Linear discriminant analysis (LDA) is one of the well-known schemes for feature extraction and dimensionality reduction of labeled data. Recently, two-dimensional LDA (2DLDA) for matrices such as images has been reformulated into symmetric 2DLDA (S2DLDA), which is solved by an iterative algorithm. In this paper, we propose a non-iterative S2DLDA and experimentally show that the proposed method achieves comparable classification accuracy with the conventional S2DLDA, while the proposed method is computationally more efficient than the conventional S2DLDA.

'Super Hi-Vision' (SHV) is promising as a future form of television. It is an ultra-high definition TV system that has 16 times the number of pixels of HDTV and employs a 22.2 multichannel sound system. It offers superior presence and gives the impression of reality. The information bitrates of the current prototypes range from 24 to 72 Gbit/s, and a fiber optic transmission system is needed to transfer even just one channel. This paper describes the optical transmission technologies that have been developed for SHV inter-equipment connects and links between outdoor sites and broadcasting stations.

Today, practical semiconductor products are an integral part of our lives and the infrastructure of society, and this trend will continue in the future. New areas of application will expand into medical, environmental, and agriculture (food)-related fields in addition to the conventional information and communication technology (ICT)-related field. Low-cost semiconductor devices with advanced functions have thus far been realized by miniaturization. However, we are now approaching the physical limit of miniaturization, and also, the investment required for new semiconductor manufacturing facilities has become huge. Under such circumstances, we propose an approach based on semiconductor devices called microcube chips and ideas of semiconductor development, i.e., agile integration and "inch-fab." Our approach is expected to contribute to expanding the range of companies that can fabricate semiconductor devices to include small-size companies, exploring new applications of semiconductor devices, and providing a wide variety of semiconductor devices at a low cost from the semiconductor industry.