Yan REN Guilin WANG Yunhong HU Qiuyan WANG
In this paper, we first propose a notion of multiple authorities attribute-based designated confirmer signature scheme with unified verification. In a multiple authorities attribute-based designated confirmer signature scheme with unified verification, both the signer and the designated confirmer can run the same protocols to confirm a valid signature or disavow an invalid signature. Then, we construct a multiple authorities attribute-based designated confirmer signature scheme with unified verification. Finally, we prove the correctness and security of the proposed scheme.
In this letter, we propose a novel kind of uncertain query, top (k1,k2) query. The x-tuple model and the possible world semantics are used to describe data objects in uncertain datasets. The top (k1,k2) query is going to find k2 x-tuples with largest probabilities to be the result of top k1 query in a possible world. Firstly, we design a basic algorithm for top (k1,k2) query based on dynamic programming. And then some pruning strategies are designed to improve its efficiency. An improved initialization method is proposed for further acceleration. Experiments in real and synthetic datasets prove the performance of our methods.
Tomoya MATSUZAKI Takahiro ISHINABE Hideo FUJIKAKE
We investigated a control of the crystalline orientation of soluble organic semiconductor single crystals using liquid crystal solvents aligned by the electric field to improve the performance of organic thin-film transistors. We clarified that the semiconductor single crystal grows to the direction parallel to the liquid crystal alignment oriented by the lateral electric field.
Hironao SANO Ryota ISHIDA Tatsuya KURA Shunsuke FUJITA Shigeki NAKA Hiroyuki OKADA Takeshi TAKAI
Transparent organic light-emitting diodes (TOLEDs) were investigated with top electrode of indium-tin-oxide (ITO) by ion-plating method. High deposition rate of 4.4 nm/s was realized without plasma damage of under organic layer. In the TOLEDs with inverted structure, high transmittance of over 75% at 550 nm and bright emission of 1,850 and 1,410 cd/m2, from bottom and top side at 163 mA/cm2, respectively, were obtained.
Xiao ZHAO Lifeng HE Bin YAO Yuyan CHAO
This paper presents a new connected component labeling algorithm. The proposed algorithm scans image lines every three lines and processes pixels three by three. When processing the current three pixels, we also utilize the information obtained before to reduce the repeated work for checking pixels in the mask. Experimental results demonstrated that our method is more efficient than the fastest conventional labeling algorithm.
Dong-Hyun LIM Minook KIM Hyung-Min PARK
This letter presents a method for active noise cancelation (ANC) for headphone application. The method improves the performance of ANC by deriving a flexible independent component analysis (ICA) algorithm in a hybrid structure combining feedforward and feedback configurations with correlation-based wind detection. The effectiveness of the method is demonstrated through simulation.
Kun JIANG Xingshen SONG Yuexiang YANG
Index compression is partially responsible for the current performance achievements of Internet search engines. Among many latest compression techniques, Simple9 can pack as many integers as possible into a single 32-bit machine word using 9 different padding modes. However, the number of wasted bits in Simple9 remains large. In previous works, researchers have focused on reducing the unused trailing bits of the padding modes and have proposed various additional modes that make full use of the cases of the status bits. Instead, we focus on the wasted bits in the integer list, padding extra zeros for a complete dense mode when the number of integers is not enough to fit a complete mode. More precisely, we first propose a novel index compression method called SimpleD with dense padding modes to achieve a more compact storage compared with that of Simple9. We then design an innovative metric for extracting the inserted extra zero integers during the decoding phase. Experiments on the TREC WT2G and GOV2 datasets show that our encoder outperforms Simple9 while still retaining a very fast decompression speed.
Mototaka OCHI Yoko SHIDA Hiroyuki OKUNO Hiroshi GOTO Toshihiro KUGIMIYA Moriyoshi KANAMARU
An Al-N system optical absorption layer has been developed, to be used for Al-based metal mesh electrodes on touch screen panels. The triple-layered electrode effectively suppresses the optical reflection in both visible light and the blue color region and exhibits excellent wet etching property that accommodates micro-fabrication. Due to its high noise immunity and contact sensitivity originating from its low electrical resistivity, the proposed metal mesh electrodes are useful for touch-sensitive panels in the next generation ultra-high-resolution displays.
Yuki KOGA Tokiyoshi MATSUDA Mutsumi KIMURA Dapeng WANG Mamoru FURUTA Masashi KASAMI Shigekazu TOMAI Koki YANO
We have developed a capacitance sensor of frequency modulation for integrated touchpanels using amorphous In-Sn-Zn-O (α-ITZO) thin-film transistors (TFTs). This capacitance sensor consists of a ring oscillator, whose one stage is replaced by a reset transistor, sensing transistor, and sensing electrode. The sensing electrode is prepared as one terminal to form a sensing capacitor when the other terminal is added by a finger. The ring oscillator consists of pseudo CMOS inverters. We confirm that the oscillation frequency changes when the other terminal is added. This result suggests that this capacitance sensor can be applied to integrated touchpanels on flatpanel displays.
Hiroaki TAKEBE Yusuke UEHARA Seiichi UCHIDA
Anchor graph hashing (AGH) is a promising hashing method for nearest neighbor (NN) search. AGH realizes efficient search by generating and utilizing a small number of points that are called anchors. In this paper, we propose a method for improving AGH, which considers data distribution in a similarity space and selects suitable anchors by performing principal component analysis (PCA) in the similarity space.
Sheng-Ju KU Yuan OUYANG Chiachi HUANG
The technique of partial transmit sequences (PTS) is effective in reducing the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals. However, the conventional PTS (CPTS) scheme has high computation complexity because it needs several inverse fast Fourier transform (IFFT) units and an optimization process to find the candidate signal with the lowest PAPR. In this paper, we propose a new low-complexity PTS scheme for OFDM systems, in which a hybrid subblock partition method (SPM) is used to reduce the complexity that results from the IFFT computations and the optimization process. Also, the PAPR reduction performance of the proposed PTS scheme is further enhanced by multiplying a selected subblock with a predefined phase rotation vector to form a new subblock. The time-domain signal of the new subblock can be obtained simply by performing a circularly-shift-left operation on the IFFT output of the selected subblock. Computer simulations show that the proposed PTS scheme achieves a PAPR reduction performance close to that of the CPTS scheme with the pseudo-random SPM, but with much lower computation complexity.
Yuta IDA Chang-Jun AHN Takahiro MATSUMOTO Shinya MATSUFUJI
Amplify-and-forward (AF) relay multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems can achieve high data rate and high quality communications. On the other hand, it has to estimate all channels between the source-relay and relay-destination nodes in the destination node. In MIMO/OFDM systems, high time resolution carrier interferometry (HTRCI) has been proposed to achieve an accurate channel estimation (CE) with a small number of pilot signals. However, since it has many interferences, an accurate CE is not obtained and the system performance is degraded in AF relay MIMO/OFDM systems. Therefore, in this paper, we propose the complex HTRCI (C-HTRCI) pilot signal and the enhanced minimum mean square error (E-MMSE) equalization to achieve an accurate CE and to improve the system performance for AF relay MIMO/OFDM systems.
Chuan LV Tongjiang YAN Guozhen XIAO
Based on a unified representation of generalized cyclotomic classes, every generalized cyclotomic sequence of order d over $Z_{p_{1}^{e_{1}}p_{2}^{e_{2}}cdots p_{r}^{e_{r}}}$ is shown to be a sum of d-residue sequences over $Z_{p_{s}^{e_{s}}}$ for $sin {1,2,cdots,r }$. For d=2, by the multi-rate approach, several generalized cyclotomic sequences are explicitly expressed by Legendre sequences, and their linear complexity properties are analyzed.
Tatsuki KAWAGUCHI Yoshinori DOBASHI Tsuyoshi YAMAMOTO
Controlling fluid simulation is one of the important research topics in computer graphics. In this paper, we focus on controlling the simulation of cumuliform cloud formation. Using a previously proposed method for controlling cloud simulation the convergence speed is very slow; therefore, it takes a long time before the clouds form the desired shapes. We improved the method and accelerated the convergence by introducing a new mechanism for controlling the amount of water vapor added. We demonstrate the effectiveness of the proposed method by several examples.
Xiao WU Zhou JIN Dan NIU Yasuaki INOUE
An effective time-step control method is proposed for the damped pseudo-transient analysis (DPTA). This method is based on the idea of the switched evolution/relaxation method which can automatically adapt the step size for different circuit states. Considering the number of iterations needed for the convergence of the Newton-Raphson method, the new method adapts the suitable time-step size with the status of previous steps. By numerical examples, it is proved that this method can improve the simulation efficiency and convergence for the DPTA method to solve nonlinear DC circuits.
Sun-Mi PARK Ku-Young CHANG Dowon HONG Changho SEO
A field multiplication in the extended binary field is often expressed using Toeplitz matrix-vector products (TMVPs), whose matrices have special properties such as symmetric or triangular. We show that such TMVPs can be efficiently implemented by taking advantage of some properties of matrices. This yields an efficient multiplier when a field multiplication involves such TMVPs. For example, we propose an efficient multiplier based on the Dickson basis which requires the reduced number of XOR gates by an average of 34% compared with previously known results.
Yukio OGAWA Go HASEGAWA Masayuki MURATA
In a multi-tenant data center, nodes and links of tenants' virtual networks (VNs) share a single component of the physical substrate network (SN). The failure of a single SN component can thereby cause the simultaneous failures of multiple nodes and links in a single VN; this complex of failures must significantly disrupt the services offered on the VN. In the present paper, we clarify how the fault tolerance of each VN is affected by a single SN failure, especially from the perspective of VN allocation in the SN. We propose a VN allocation model for multi-tenant data centers and formulate a problem that deals with the bandwidth loss in a single VN due a single SN failure. We conduct numerical simulations (with the setting that has 1.7×108bit/s bandwidth demand on each VN, (denoted by Ci)). When each node in each VN is scattered and mapped to an individual physical server, each VN can have the minimum bandwidth loss (5.3×102bit/s (3.0×10-6×Ci)) but the maximum required bandwidth between physical servers (1.0×109bit/s (5.7×Ci)). The balance between the bandwidth loss and the required physical resources can be optimized by assigning every four nodes of each VN to an individual physical server, meaning that we minimize the bandwidth loss without over-provisioning of core switches.
Mingyi GAO Takayuki KUROSU Karen SOLIS-TRAPALA Takashi INOUE Shu NAMIKI
High gain extinction ratio and stable control of the phase in phase sensitive amplification are fundamental to realize either phase regeneration or quadrature squeezing of phase modulated signals in an efficient and robust manner. In this paper, we show that a combination of our previously demonstrated “sideband-assisted” dual-pump phase sensitive amplifier with a gain extinction ratio of more than 25dB, and a phase-locked loop based stabilization technique, enable efficient QPSK quadrature squeezing. Its stable operation is exploited to realize phase de-multiplexing of QPSK signals into BPSK tributaries. The phase de-multiplexed signals are evaluated through measurement of constellation diagrams, eye diagrams and more importantly, BER curves. The de-multiplexed BPSK signals exhibited an OSNR penalty of less than 1dB compared to the back-to-back BPSK signals.
Kazuma OUCHIDA Naoki HONMA Yoshitaka TSUNEKAWA
This paper proposes a new method that combines signal modulation and FDTD (Finite-Difference Time-Domain) simulations to reduce the computation time in multiple-antenna analysis. In this method, signals are modulated so as to maintain orthogonality among the excited signals; multiple antennas are excited at the same time. This means just one FDTD simulation is needed whereas the conventional method demands as many simulations as there are transmitting antennas. The simulation of a 2×2 multi-antenna system shows that the proposed method matches the performance of the conventional method even though its computation time is much shorter.
Shoichiro KAWASHIMA Keizo MORITA Mitsuharu NAKAZAWA Kazuaki YAMANE Mitsuhiro OGAI Kuninori KAWABATA Kazuaki TAKAI Yasuhiro FUJII Ryoji YASUDA Wensheng WANG Yukinobu HIKOSAKA Ken'ichi INOUE
An 8-Mbit 0.18-µm CMOS 1T1C ferroelectric RAM (FeRAM) in a planar ferroelectric technology was developed. Even though the cell area of 2.48 µm2 is almost equal to that of a 4-Mbit stacked-capacitor FeRAM (STACK FeRAM) 2.32 µm2[1], the chip size of the developed 8-Mbit FeRAM, including extra 2-Mbit parities for the error correction code (ECC), is just 52.37 mm2, which is about 30% smaller than twice of the 4-Mbit STACK FeRAM device, 37.68mm2×2[1]. This excellent characteristic can be attributed to the large cell matrix architectures of the sectional cyclic word line (WL) that was used to increase the column numbers, and to the 1T1C bit-line GND level sensing (BGS)[2][3] circuit design intended to sense bit lines (BL) that have bit cells 1K long and a large capacitance. An access time of 52 ns and a cycle time of 77 ns in RT at a VDD of 1.8 V were achieved.