This paper presents an intuitive interaction technique for data exchange between multiple co-located devices. In the proposed system, CrossOverlayDesktop, desktop graphics of the devices are graphically overlaid with each other (i.e., alpha-blended). Users can exchange file data by the usual drag-and-drop manipulation through an overlaid area. The overlaid area is determined by the physical six degrees of freedom (6-DOF) correlation of the devices and thus changes according to users' direct movements of the devices. Because familiar operations such as drag-and-drop can be applied to file exchange between multiple devices, seamless, consistent, and thus intuitive multi-user collaboration is realized. Furthermore, dynamic overlay of desktop graphics allows users to intuitively establish communication, identify connected devices, and perform access control. For access control of the data, users can protect their own data by simply dragging them out of the overlaid area, because only the overlaid area becomes a public space. Several proof-of-concept experiments and evaluations were conducted. Results show the effectiveness of the proposed interaction technique.

Timing margin of a chip varies chip by chip due to manufacturing variability, and depends on operating environment and aging. Adaptive speed control with timing error prediction is promising to mitigate the timing margin variation, whereas it inherently has a critical risk of timing error occurrence when a circuit is slowed down. This paper presents how to evaluate the relation between timing error rate and power dissipation in self-adaptive circuits with timing error prediction. The discussion is experimentally validated using adders in subthreshold operation in a 90 nm CMOS process. We show a trade-off between timing error rate and power dissipation, and reveal the dependency of the trade-off on design parameters.

Carbon nanofibers (CNFs) were fabricated on graphite plates using "Ar+ ion sputtering method" in large amount at room temperature. The morphology of CNFs was controlled by a simultaneous carbon supply during ion sputtering. CNF-tipped cones were formed on graphite plate surfaces without carbon supply whereas those with a simultaneous carbon supply featured mainly needle-like protrusions of large size. The field electron emission (FE) properties, measured using parallel plate configurations in 10-4 Pa range, showed the threshold fields of 4.4 and 5.2 V/µm with a current density of 1 µA/cm2 for CNF-tipped cones and needle-like protrusion, respectively. Reliability test results indicated that CNF-tipped cones were more stable than needle-like protrusion. The morphological change after reliability test showed a so-called "self-regenerative" process and structure damage for CNF-tipped cones and needle-like protrusions, respectively.

In this paper, we propose a new modeling method to express discrete-time hybrid systems with parameter uncertainty as a mixed logical dynamical (MLD) model. In analysis and control of hybrid systems, there are problem formulations in which convex polyhedra are computed, but for high-dimensional systems, it is difficult to solve these problems within a practical computation time. The key idea of this paper is to use an interval method, which is one of the classical methods in verified numerical computation, and to regard an interval as an over-approximation of a convex polyhedron. By using the obtained MLD model, analysis and synthesis of robust control systems are formulated.

In this paper, we investigate the smallest value of p for which a (J,L,p)-QC LDPC code with girth 6 exists for J=3 and J=4. For J=3, we determine the smallest value of p for any L. For J=4, we determine the smallest value of p for L ≤ 301. Furthermore we provide examples of specific constructions meeting these smallest values of p.

In this paper, we propose a low-complexity, high-efficiency two-dimensional look-up table (2D LUT) for carrying out the sum-product algorithm in the decoding of low-density parity-check (LDPC) codes. Instead of employing adders for the core operation when updating check node messages, in the proposed scheme, the main term and correction factor of the core operation are successfully merged into a compact 2D LUT. Simulation results indicate that the proposed 2D LUT not only attains close-to-optimal bit error rate performance but also enjoys a low complexity advantage that is suitable for hardware implementation.

This paper presents the field uniformity characteristics in a triangular prism reverberation chamber that can be substituted for an open area test site or an anechoic chamber to measure electromagnetic interference. To improve size problems of a stirrer that is an official unit to generate a uniform field in the reverberation chamber, we suggest a diffuser of Quadratic Residue Sequence method. To validate the substitution of a diffuser for a stirrer, a diffuser is designed for 1-3 GHz, and three types of equilateral triangular prism reverberation chambers are modeled. Afterwards, the field distributions in these three reverberation chambers are both simulated and tested. Using XFDTD 6.2 of finite difference time domain method, field deviations of each structure are simulated and compared to each other. An evaluation of field uniformity is done by cumulative probability distribution which is specified in the IEC 61000-4-21. The result shows that the field uniformity in the chamber is within 6 dB tolerance and also within 3 dB standard deviation, which means a diffuser can satisfy the requirement of international standards.

This paper presents a realization of a simple antenna system for land vehicle satellite communication that is tested in experiments conducted on the Engineering Test Satellite-VIII (ETS-VIII). The developed antenna system which was mounted onto a vehicle roof is compact, light weight with simple satellite-tracking operation. In order to realize compact antennas, an onboard-power divider and switching circuit for antenna feeding control are mounted under the array antenna. A Global Positioning System (GPS) module is used to provide accurate information on the vehicle's position and bearing during travelling. A personal computer (PC) is used as the control unit and data logger, which was specifically designed for this application, allow the switching circuit control as well as the retrieving of the received power levels and error rate. The field tests reported in this paper mainly address the tracking performance of the proposed antenna system. Satisfactory results were obtained. Good received power levels and bit error rate (BER) for tracking the ETS-VIII satellite were confirmed. Furthermore, in order to grasp the environmental factors that impact the quality of land vehicle communications, we carefully captured data at obstacles such as buildings, foliages, utility poles and highway overpasses. The results showed blockage and shadowing was confirmed. Additionally, when the antenna was tested at the inclined-road for simple propagation characteristics in elevation direction, stable reception of the satellite signals was realized.

Cognitive radio systems offer the opportunity to improve the spectrum utilization by detecting unused frequency bands while avoiding interference to primary users. This paper proposes a new algorithm for spectrum sensing, which is an energy detector using a hybrid (adaptive and fixed) threshold, in order to compensate the weak points of the existing energy detector in the distorted communication channel environment. Simulation results are presented which show that the performance of the new proposed scheme is better than the existing scheme using a fixed threshold or an adaptive threshold. Additionally, the performance is investigated in terms of several parameters such as the mobile speed and the probability of false alarms. The simulation results also show that the proposed algorithm makes the detector highly robust against fading, shadowing, and interference.

We newly design time-varying low-density parity-check convolutional codes (LDPC-CCs) based on parity check polynomials of the convolutional codes with a time period of 3, and show that BER (Bit Error Rate) performance in the time-varying LDPC-CCs with a time period of 3 is better than that in the conventional time-varying LDPC-CCs with a time period of 2 in the same coding rate with the nearly equal constraint length.

This paper proposes a parallelized DVC framework that treats each bitplane independently to reduce the decoding time. Unfortunately, simple parallelization generates inaccurate bit probabilities because additional side information is not available for the decoding of subsequent bitplanes, which degrades encoding efficiency. Our solution is an effective estimation method that can calculate the bit probability as accurately as possible by index assignment without recourse to side information. Moreover, we improve the coding performance of Rate-Adaptive LDPC (RA-LDPC), which is used in the parallelized DVC framework. This proposal selects a fitting sparse matrix for each bitplane according to the syndrome rate estimation results at the encoder side. Simulations show that our parallelization method reduces the decoding time by up to 35[%] and achieves a bit rate reduction of about 10[%].

An approach to image thresholding based on the plausibility of object and background regions by adopting a co-occurrence matrix and category utility is presented. The effectiveness of the proposed method is shown through the experimental results tested on several images and compared with conventional methods.

This paper clarifies the adequacy of the linear channel coding approach for Slepian-Wolf coding of individual sequences. A sufficient condition for ensembles of linear codes from which a universal Slepian-Wolf code can be constructed is given. Our result reveals that an ensemble of LDPC codes gives a universal code for Slepian-Wolf coding of individual sequences.

We present a novel model named Integrated Latent Topic Model (ILTM), to learn and recognize natural scene category. Unlike previous work, which considered the discrepancy and common property separately among all categories, Our approach combines universal topics from all categories with specific topics from each category. As a result, the model is implemented to produce a few but specific topics and more generic topics among categories, and each category is represented in a different topics simplex, which correlates well with human scene understanding. We investigate the classification performance with variable scene category tasks. The experiments have shown our model outperforms latent-space methods with less training data.

In this paper, we propose a novel image projection technique for face recognition applications based on Fisher Linear Discriminant Analysis (LDA). The projection is performed through a couple subspace analysis for overcoming the "small sample size" problem. Also, weighted pairwise discriminant hyperplanes are used in order to provide a more accurate discriminant decision than that produced by the conventional LDA. The proposed technique has been successfully tested on three face databases. Experimental results indicate that the proposed algorithm outperforms the conventional algorithms.

Generalized quasi-cyclic (GQC) codes form a wide and useful class of linear codes that includes thoroughly quasi-cyclic codes, finite geometry (FG) low density parity check (LDPC) codes, and Hermitian codes. Although it is known that the systematic encoding of GQC codes is equivalent to the division algorithm in the theory of Grobner basis of modules, there has been no algorithm that computes Grobner basis for all types of GQC codes. In this paper, we propose two algorithms to compute Grobner basis for GQC codes from their parity check matrices; we call them echelon canonical form algorithm and transpose algorithm. Both algorithms require sufficiently small number of finite-field operations with the order of the third power of code-length. Each algorithm has its own characteristic. The first algorithm is composed of elementary methods and is appropriate for low-rate codes. The second algorithm is based on a novel formula and has smaller computational complexity than the first one for high-rate codes with the number of orbits (cyclic parts) less than half of the code length. Moreover, we show that a serial-in serial-out encoder architecture for FG LDPC codes is composed of linear feedback shift registers with the size of the linear order of code-length; to encode a binary codeword of length n, it takes less than 2n adder and 2n memory elements.

The novel SCR-based (silicon controlled rectifier) device for ESD power clamp is presented in this paper. The proposed device has a high holding voltage and a high triggering current characteristic. These characteristics enable latch-up immune normal operation as well as superior full chip ESD protection. The device has a small area in requirement robustness in comparison to ggNMOS (gate grounded NMOS). The proposed ESD protection device is designed in 0.25 µm and 0.5 µm CMOS Technology. In the experimental result, the proposed ESD clamp has a double trigger characteristic, a high holding voltage of 4 V and a high trigger current of above 350 mA. The robustness has measured to HBM 8 kV (HBM: Human Body Model) and MM 400 V (MM: Machine Model). The proposed device has a high level It2 of 52 mA/ µm approximately.

In this paper, a low power current protection circuit implemented in a low dropout regulator (LDO) is presented. The proposed circuit, designed in a 0.35 µm CMOS process, provides a precise limiting current as well as holding current with low dependency on both supply voltage and regulator output voltage. The experimental results showed that the proposed circuit is operable in the regulator output voltage range from VOUT=1.2 V to VOUT=3.6 V and supply voltage range from VDD=VOUT+0.5 V to VDD=5.6 V. Since the proposed circuit is composed of few simple basic circuits such as a comparator and a Schmitt Trigger, it has a low current consumption of less than ISS=0.82 µA at a load current of ILOAD=200 mA. This makes the circuit suitable for low power and low voltage LDO design.

This paper presents a field penetration characteristic, into a metallic wall with a narrow slot, due to a nearby dipole source. Coupled integral equations are derived and solved by applying Galerkin's method of moments (MoM) for calculating the penetrating electric field. It is shown that the 26 dB attenuation level field penetration into the narrow slot occurs at the dipole source position of much more than about 0.6 λ separation distance along the lateral direction from the slot center. It is also found that the 30 dB attenuation levels field penetration appear at the observation positions of much more than about 0.5 λ along the direction of the slot length and about 1.07 λ separation distance along the direction of the slot width from the slot center.

In this paper, the research advances in SIW-like (Substrate Integrated Waveguide-like) guided wave structures and their applications in the State Key Laboratory of Millimeter Waves of China is reviewed. Our work is concerned with the investigations on the propagation characteristics of SIW, half-mode SIW (HMSIW) and the folded HMSIW (FHMSIW) as well as their applications in microwave and millimeter wave filters, diplexers, directional couplers, power dividers, antennas, power combiners, phase shifters and mixers etc. Selected results are presented to show the interesting features and advantages of those new techniques.