Jae-Hoon JANG Sung-Hak LEE Kyu-Ik SOHNG
The Processing of high-dynamic-range (HDR) images is embodied by a lot of algorithms. This paper takes notice of one of these algorithms which is presented using the iCAM06. iCAM06 is capable of making color appearance predictions of HDR images based on CIECAM02 color predictions and incorporating spatial process models in the human visual system (HVS) for contrast enhancement. The effect of user controllable factors of iCAM06 was investigated and the best factor which corresponds with Breneman's corresponding color data sets was found. A suggested model improves color matching predictions for the corresponding color data set in Breneman's experiment.
Junichi NAKAYAMA Yasuhiko TAMURA Kiyoshi TSUTSUMI
By use of the shadow theory developed recently, this paper deals with the transverse electric (TE) wave diffraction by a perfectly conductive periodic array of rectangular grooves. A set of equations for scattering factors and mode factors are derived and solved numerically. In terms of the scattering factors, diffraction amplitudes and diffraction efficiencies are calculated and shown in figures. It is demonstrated that diffraction efficiencies become discontinuous at an incident wave number where the incident wave is switched from a propagating wave to an evanescent one, whereas scattering factors and diffraction amplitudes are continuous even at such an incident wave number.
Kentaroh KATOH Kazuteru NAMBA Hideo ITO
This paper proposes a scan design for delay fault testability of dual circuits. In normal operation mode, each proposed scan flip flop operates as a master-slave flip flop. In test mode, the proposed scan design performs scan operation using two scan paths, namely master scan path and slave scan path. The master scan path consists of master latches and the slave scan path consists of slave latches. In the proposed scan design, arbitrary two-patterns can be set to flip flops of dual circuits. Therefore, it achieves complete fault coverage for robust and non-robust testable delay fault testing. It requires no extra latch unlike enhanced scan design. Thus the area overhead is low. The evaluation shows the test application time of the proposed scan design is 58.0% of that of the enhanced scan design, and the area overhead of the proposed scan design is 13.0% lower than that of the enhanced scan design. In addition, in testing of single circuits, it achieves complete fault coverage of robust and non-robust testable delay fault testing. It requires smaller test data volume than the enhanced scan design in testing of single circuits.
Yukiko YAMAUCHI Sayaka KAMEI Fukuhito OOSHITA Yoshiaki KATAYAMA Hirotsugu KAKUGAWA Toshimitsu MASUZAWA
A desired property of large distributed systems is self adaptability against the faults that occur more frequently as the size of the distributed system grows. Self-stabilizing protocols provide autonomous recovery from finite number of transient faults. Fault-containing self-stabilizing protocols promise not only self-stabilization but also containment of faults (quick recovery and small effect) against small number of faults. However, existing composition techniques for self-stabilizing protocols (e.g. fair composition) cannot preserve the fault-containment property when composing fault-containing self-stabilizing protocols. In this paper, we present Recovery Waiting Fault-containing Composition (RWFC) framework that provides a composition of multiple fault-containing self-stabilizing protocols while preserving the fault-containment property of the source protocols.
Liping WANG Yusheng JI Fuqiang LIU
The integration of multihop relays with orthogonal frequency-division multiple access (OFDMA) cellular infrastructures can meet the growing demands for better coverage and higher throughput. Resource allocation in the OFDMA two-hop relay system is more complex than that in the conventional single-hop OFDMA system. With time division between transmissions from the base station (BS) and those from relay stations (RSs), fixed partitioning of the BS subframe and RS subframes can not adapt to various traffic demands. Moreover, single-hop scheduling algorithms can not be used directly in the two-hop system. Therefore, we propose a semi-distributed algorithm called ASP to adjust the length of every subframe adaptively, and suggest two ways to extend single-hop scheduling algorithms into multihop scenarios: link-based and end-to-end approaches. Simulation results indicate that the ASP algorithm increases system utilization and fairness. The max carrier-to-interference ratio (Max C/I) and proportional fairness (PF) scheduling algorithms extended using the end-to-end approach obtain higher throughput than those using the link-based approach, but at the expense of more overhead for information exchange between the BS and RSs. The resource allocation scheme using ASP and end-to-end PF scheduling achieves a tradeoff between system throughput maximization and fairness.
Kiyoshi NIKAWA Shouji INOUE Tatsuoki NAGAISHI Toru MATSUMOTO Katsuyoshi MIURA Koji NAKAMAE
We have proposed and successfully demonstrated a two step method for localizing defects on an LSI chip. The first step is the same as a conventional laser-SQUID (L-SQUID) imaging where a SQUID and a laser beam are fixed during LSI chip scanning. The second step is a new L-SQUID imaging where a laser beam is stayed at the point, located in the first step results, during SQUID scanning. In the second step, a SQUID size (Aeff) and the distance between the SQUID and the LSI chip (ΔZ) are key factors limiting spatial resolution. In order to improve the spatial resolution, we have developed a micro-SQUID and the vacuum chamber housing both the micro-SQUID and the LSI chip. The Aeff of the micro-SQUID is a thousand of that of a conventional SQUID. The minimum value of ΔZ was successfully reduced to 25 µm by setting both the micro-SQUID and an LSI chip in the same vacuum chamber. The spatial resolution in the second step was shown to be 53 µm. Demonstration of actual complicated defects localization was succeeded, and this result suggests that the two step localization method is useful for LSI failure analysis.
In this paper, we derive the exact average symbol error probability (SEP) of M-ary phase-shift keying and quadrature amplitude modulation signals over Stacy fading channels. The Stacy fading is modelled by a three-parameter generalized gamma or physically α-µ fading distribution, spanning a wide range of small-scale fading such as Rayleigh, Nakagami-m, and Weibull fading. The average SEP is generally expressed in terms of (generalized) Fox's H-functions, which particularizes to the previously known results for some special cases. We further analyze the diversity order achieved by orthogonal space-time block codes in multiple-input multiple-output (MIMO) Stacy fading channels.
Dongju KIM Myonghee PARK Jeongho PARK Kyunbyoung KO
The authors present an accurate analysis for multicode code division multiple access (CDMA) systems equipped with a multipath interference canceler (MPIC) over multipath fading channels. This letter verifies that the previous analysis has used the additional Gaussian approximation (AGA) for multipath interferences so that there is the performance mismatch between the previous analysis and simulations. Furthermore, it is confirmed that the proposed analysis, which does not use AGA, provides an analytical bound.
Kentaroh KATOH Kazuteru NAMBA Hideo ITO
This paper presents a scan design for delay fault testability of 2-rail logic circuits. The flip flops used in the scan design are based on master-slave ones. The proposed scan design provides complete fault coverage in delay fault testing of 2-rail logic circuits. In two-pattern testing with the proposed scan design, initial vectors are set using the set-reset operation, and the scan-in operation for initial vectors is not required. Hence, the test application time is reduced to about half that of the enhanced scan design. Because the additional function is only the set-reset operation of the slave latch, the area overhead is small. The evaluation shows that the differences in the area overhead of the proposed scan design from those of the standard scan design and the enhanced scan design are 2.1 and -14.5 percent on average, respectively.
Dongju KIM Kyunbyoung KO Jeongho PARK Daesik HONG
This letter presents an analytical method for 64-QAM CDMA systems equipped with a multipath interference canceler (MPIC) over multipath fading channels. Numerical results obtained from the proposed analysis indicate that an MPIC is required in order to mitigate the effects of multipath interference and to effectively increase the system capacity.
This paper proposes a method providing efficient test compression. The proposed method is for robust testable path delay fault testing with scan design facilitating two-pattern testing. In the proposed method, test data are interleaved before test compression using statistical coding. This paper also presents test architecture for two-pattern testing using the proposed method. The proposed method is experimentally evaluated from several viewpoints such as compression rates, test application time and area overhead. For robust testable path delay fault testing on 11 out of 20 ISCAS89 benchmark circuits, the proposed method provides better compression rates than the existing methods such as Huffman coding, run-length coding, Golomb coding, frequency-directed run-length (FDR) coding and variable-length input Huffman coding (VIHC).
Masataka AKANE Yasuyuki NOGAMI Yoshitaka MORIKAWA
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.
Shouhei KOUSAI Mototsugu HAMADA Rui ITO Tetsuro ITAKURA
A novel automatic quality factor (Q) tuning scheme for an low-power and wideband active-RC filter is presented. Although Q-tuning is effective to reduce the power consumption of wideband active-RC filters, there are several problems since the Q-tuning normally relies on a magnitude locked loop (MLL). MLL is not accurate due to the amplitude detection circuits, and occupied area and power consumption tends to be large due to its complexity. In addition, flexibility to the reference signal may be the problem, since the reference signal which has a fixed accurate frequency is required. In order to solve these problems, we propose a Q-tuning scheme, which does not require a MLL. Therefore, proposed Q-tuning scheme has good accuracy, small die area, low power consumption and flexibility to the reference signal. In our proposed scheme, Q is tuned by adjusting the phase of an integrator to 90 degrees. The phase of an integrator is adjusted by detecting and controlling the oscillation frequency of a two-stage ring-integrator to the cutoff frequency of a filter, since the phase shift of an integrator is exactly 90 degrees at the oscillation frequency. The frequency is easily detected and controlled by counters and variable resistors, respectively. The Q-tuning circuit with a 5th-order Chebyshev LPF is implemented in a 0.13 µm CMOS technology. The tuning circuit occupies 0.12 mm2 and consumes 2.6 mW from 1.2 V supply.
Minoru SAKAIRI Ayako NISHIMURA Daisuke SUZUKI
For the purpose of the application of odor to information technology, we have developed an odor-emitting apparatus coupled with chemical capsules made of alginic acid polymer. This apparatus consists of a chemical capsule cartridge including chemical capsules of odor ingredients, valves to control odor emission, and a temperature control unit. Different odors can be easily emitted by using the apparatus. We have developed an integrated system of vision, audio and olfactory information in which odor strength can be controlled coinciding with on-screen moving images based on analytical results from the odor scanner.
In this paper, the impacts of using multiple transmit antennas under doubly correlated MIMO channels on CDMA uplink code acquisition is studied. The performance of a MIMO code acquisition system is analyzed by considering spatial fading correlations, which depend on antenna spacing and azimuth spread at both MS and BS. The detection performance and mean acquisition time in the presence of spatially correlated MIMO channel are presented on a frequency selective fading channel and compared with the cases of spatial fading decorrelation via numerical evaluation. It is observed that the acquisition performance relies on the degree of spatial fading correlations. In addition, it is surprisingly seen that a MIMO code acquisition system provides worse performance than SIMO.
Xiaobo DENG Yiming PI Zhenglin CAO
A new constant false alarm rate (CFAR) detection scheme based on the goodness-of-fit (GoF) test is proposed to deal with the problem of extended object detection in high resolution synthetic aperture radar (SAR) images. The performance of this detector is compared with that of the traditional detectors using the MSTAR database. Results show that the proposed detector is superior to the traditional detectors in controlling false alarms in nonhomogeneous environment where boundaries widely exist.
Keiji GOTO Toru KAWANO Toyohiko ISHIHARA
We study the high-frequency asymptotic analysis methods for the scattered fields by a cylindrically curved conducting surface excited by the incident wave on the curved surface from the convex side. We first derive the novel hybrid ray-mode solution for the scattered fields near the concave surface by solving a canonical problem formulated under the assumption that the cylindrically curved conducting surface possesses only one edge. Then by applying the ray tracing technique and the idea of Keller's GTD (Geometrical Theory of Diffraction), the solutions derived for the canonical problem are extended to account for the problem of the radiation from and the scattering by the other edge of the cylindrically curved surface. We confirm the validity of the novel asymptotic representations proposed in the present study by comparing both with the numerical results obtained from the method of moment and the experimental results performed in the anechoic chamber.
Yoshiaki SONE Wataru IMAJUKU Naohide NAGATSU Masahiko JINNO
Bolstering survivable backbone networks against multiple failures is becoming a common concern among telecom companies that need to continue services even when disasters occur. This paper presents a multiple-failure recovery scheme that considers the operation and management of optical paths. The presented scheme employs scheme escalation from pre-planned restoration to full rerouting. First, the survivability of this scheme against multiple failures is evaluated considering operational constraints such as route selection, resource allocation, and the recovery order of failed paths. The evaluation results show that scheme escalation provides a high level of survivability even under operational constraints, and this paper quantitatively clarifies the impact of these various operational constraints. In addition, the fundamental functions of the scheme escalation are implemented in the Generalized Multi-Protocol Label Switching control plane and verified in an optical-cross-connect-based network.
This paper deals with a new formulation for the diffraction of a plane wave by a periodic grating. As a simple example, the diffraction of a transverse magnetic wave by a perfectly conductive periodic array of rectangular grooves is discussed. On the basis of a shadow hypothesis such that no diffraction takes place and only the reflection occurs with the reflection coefficient -1 at a low grazing limit of incident angle, this paper proposes the scattering factor as a new concept. In terms of the scattering factor, several new formulas on the diffraction amplitude, the diffraction efficiency and the optical theorem are obtained. It is newly found that the scattering factor is an even function due to the reciprocity. The diffraction efficiency is defined for a propagating incident wave as well as an evanescent incident wave. Then, it is theoretically found that the 0th order diffraction efficiency becomes unity and any other order diffraction efficiencies vanish when a real angle of incidence becomes low grazing. Numerical examples of the scattering factor and diffraction efficiency are illustrated in figures.
Muhammad Mahbub ALAM Choong Seon HONG
For successful data collection in wireless sensor networks, it is important to ensure that the required delivery ratio is maintained while keeping a fair rate for every sensor. Furthermore, emerging high-rate applications might require complete reliability and the transfer of large volume of data, where persistent congestion might occur. These requirements demand a complete but efficient solution for data transport in sensor networks which reliably transports data from many sources to one or more sinks, avoids congestion and maintains fairness. In this paper, we propose congestion-aware and rate-controlled reliable transport (CRRT), an efficient and low-overhead data transport mechanism for sensor networks. CRRT uses efficient MAC retransmission to increase one-hop reliability and end-to-end retransmission for loss recovery. It also controls the total rate of the sources centrally, avoids the congestion in the bottleneck based on congestion notifications from intermediate nodes and centrally assigns the rate to the sources based on rate assignment policy of the applications. Performance of CRRT is evaluated in NS-2 and simulation results demonstrate the effectiveness of CRRT.