This paper presents a novel test data compression scheme for SoCs based on block merging and compatibility. The technique exploits the properties of compatibility and inverse compatibility between consecutive blocks, consecutive merged blocks, and two halves of the encoding merged block itself to encode the pre-computed test data. The decompression circuit is simple to be implemented and has advantage of test-independent. In addition, the proposed scheme is applicable for IP cores in SoCs since it compresses the test data without requiring any structural information of the circuit under test. Experimental results demonstrate that the proposed technique can achieve an average compression ratio up to 68.02% with significant low test application time.

To implement a wideband bandpass filter with improved skirt-selectivity and out-band characteristics, a new parallel-coupled three-line unit with two short-circuited stubs symmetrically-loaded at the center line is proposed. Unlike most traditional ones, the passband of the proposed parallel-coupled three-line structure is based on the cross-coupling between non-adjacent lines rather than the direct-coupling between adjacent ones, whereas a pair of attenuation poles is found in the stopbands. After revealing its work mechanism, an efficient filter-design-scheme is correspondingly proposed for the presented structure. Firstly, based on a chebyshev-filter synthesis theory, a wideband passband filter consisting of a parallel-coupled two-line and two short-circuited stubs loaded at the input- and output- ports is designed. Furthermore, by putting a properly-designed 3/4-wavelength stepped-impedance resonator (SIR) in between the parallel-coupled two lines, two attenuation poles are then realized at the frequencies very close to the cutoff ones. Accordingly, the roll-off characteristics of the filter are significantly-improved to greater than 100,dB/GHz. Furthermore, two-section open-ended stubs are used to replace the short-circuited ones to realize a pair of extra attenuation poles in stopbands. To validate the proposed techniques, a wideband filter with a bandwidth of 3--5,GHz (Fractional bandwidth (FBW) $= (5,GHz-3,GHz)/4,GHz =50%)$ was designed, simulated, fabricated and measured. The measured responses of the filter agree well with the simulation and theoretical ones, which validates the effectiveness of the newly-proposed three-line unit and the corresponding design scheme.

Recent progress in research on the finite element method (FEM) for optical waveguide design and analysis is reviewed, focusing on the author's works. After briefly reviewing fundamentals of FEM such as a theoretical framework, a conventional nodal element, a newly developed edge element to eliminate nonphysical, spurious solutions, and a perfectly matched layer to avoid undesirable reflections from computational window edges, various FEM techniques for a guided-mode analysis, a beam propagation analysis, and a waveguide discontinuity analysis are described. Some design examples are introduced, including current research activities on multi-core fibers.

Nonlinearity compensation algorithm and soft-decision forward error correction (FEC) are considered as key technologies for future high-capacity and long-haul optical transmission system. In this report, we experimentally demonstrate the following three benefits brought by low complexity perturbation back-propagation nonlinear compensation algorithm in 224Gb/s DP-16QAM transmission over large-Aeff pure silica core fiber; (1) improvement of pre-FEC bit error ratio, (2) reshaping noise distribution to more Gaussian, and (3) reduction of cycle slip probability.

Location fingerprinting utilizes periodic beacons transmitted by Wireless Local Area Network (WLAN) Access Points (APs) to provide localization in indoor environments. Currently no method is able to quantify the effectiveness of localization information provided by individual APs. Such a metric would enable the optimal placement of new APs as well as eliminating redundant APs so as to reduce the resources consumed by indoor localization software in client devices. This paper proposes LocationInfo, a metric that utilizes walk test data for quantifying the localization efficacy of APs. The performance of LocationInfo is evaluated using two experimental settings. First, it is used for identifying the optimal location for new APs. Second, it is used for filtering out excess APs in a crowded WLAN environment. In both experiments, LocationInfo outperforms existing metrics.

Currently, a correspondent host will have difficulties in establishing a direct session path to a mobile host because of the partial deployment of MIPv6-aware mobile hosts. Even MIPv6-aware hosts will spend up to several seconds to obtain the new location of the mobile host during Layer 3 (L3) handover. This paper proposes an application-level mobility management scheme that can solve the problems related to the increase of Internet traffic end-to-end delay under the current situation that most of the mobile devices are MIPv6-non-aware. The proposed Secure Mobility Management Application (SMMA) enables the updates of care-of address to be faster and more reliable even when L3 handovers occur frequently. SMMA uses a cross-layer approach for session mobility management with the support of Binding Updates to the home agent via IPSec tunnels. The main feature of SMMA is to handle the session-related mobility management for which operation starts just after the completion of name resolution as a pre-call mobility management, which operates in conjunction with the DNS. Our session-related mobility management introduces three new signaling messages: SS-Create for session state creation, SS-Refresh for session state extension and SS-Renewal for updating new care-of address at the mid-session. Finally, this paper analyzes the work load imposed on a mobile host to create a session state and the security strength of the SS-Renewal message, which depends on the key size used.

The body-of-revolution finite-difference time-domain method (BOR-FDTD) based on the locally one-dimensional (LOD) scheme is extended to a frequency-dependent version for the analysis of the Drude and Drude-Lorentz models. The formulation is simplified with a fundamental scheme, in which the number of arithmetic operations is reduced by 40% in the right-hand sides of the resultant equations. Efficiency improvement of the LOD-BOR-FDTD is discussed through the analysis of a plasmonic rod waveguide and a plasmonic grating.

This paper presents a new information-theoretical evaluation method, for the resistance of cryptographic implementation against side-channel attacks. In conventional methods, the results of actual attacks have been often used empirically. However, these experimental methods have some problems. In the proposed method, a side-channel attack is regarded as a communication channel model. Then, a new evaluation index “the amount of leakage information” can be defined. The upper-bound of this index is estimated as the channel capacity. The proposed evaluation using this index can avoid the problems of conventional methods. Consequently, the proposed method provides some benefits: (1) It provides rationale for evaluation; (2) It enables execution of numerical evaluation and mutual evaluation among several kinds of countermeasures. This research achieves a unification of evaluation indexes for resistance against side-channel attack. This paper applies the proposed method to correlation power analysis against implementations of stream cipher Enocoro-128 v2. As a result, we confirmed its effectiveness.

This paper presents a measurement circuit structure for capturing SET pulse-width suppressing pulse-width modulation and within-die process variation effects. For mitigating pulse-width modulation while maintaining area efficiency, the proposed circuit uses massively parallelized short inverter chains as a target circuit. Moreover, for each inverter chain on each die, pulse-width calibration is performed. In measurements, narrow SET pulses ranging 5ps to 215ps were obtained. We confirm that an overestimation of pulse-width may happen when ignoring die-to-die and within-die variation of the measurement circuit. Our evaluation results thus point out that calibration for within-die variation in addition to die-to-die variation of the measurement circuit is indispensable.

In this study, we address the problem of salient region detection. Recently, saliency detection with contrast based approaches has shown to give promising results. However, different individual features exhibit different performance. In this paper, we show that the combination of color uniqueness and color spatial distribution is an effective way to detect saliency. A Color Adaptive Thresholding Watershed Fusion Segmentation (CAT-WFS) method is first given to retain boundary information and delete unnecessary details. Based on the segmentation, color uniqueness and color spatial distribution are defined separately. The color uniqueness denotes the color rareness of salient object, while the color spatial distribution represents the color attribute of the background. Aiming at highlighting the salient object and downplaying the background, we combine the two characters to generate the final saliency map. Experimental results demonstrate that the proposed algorithm outperforms existing salient object detection methods.

This paper proposes a new spectrum sharing scheme which uses one-sided collaboration. In the proposed system, the transmitter of the secondary system relays the primary signal and overlays its own data on the retransmitted primary signal. The results of the theoretical analysis show that the proposed scheme with regenerative relay allows the secondary system to communicate at the same speed as the primary system that disregards the presence of the secondary system.

The recently suggested regular-type triangular quadrature amplitude modulation (TQAM) provides considerable power gain over square quadrature amplitude modulation (SQAM) at the expense of a slight increase in detection complexity. However, the power gain of the TQAM is limited due to the constraint that signal points should be regularly located at the vertexes of contiguous equilateral triangles. In this paper, we investigate two irregular (optimum and suboptimum) TQAMs where signal points are irregularly distributed while preserving the equilateral triangular lattice, and calculate achievable power gains of the proposed constellations. We also address optimum and suboptimum bit stream mapping methods and suggest a simple and optimum detection method for the constellations to be meaningful in practical implementation, and present analytical and simulation results. The proposed constellations can provide the asymptotic power gains of 0.825dB and 0.245dB over SQAM and regular TQAM, respectively.

The k-error linear complexity of periodic sequences is an important security index of stream cipher systems. By using an interesting decomposing approach, we investigate the intrinsic structure for the set of 2n-periodic binary sequences with fixed complexity measures. For k ≤ 4, we construct the complete set of error vectors that give the k-error linear complexity. As auxiliary results we obtain the counting functions of the k-error linear complexity of 2n-periodic binary sequences for k ≤ 4, as well as the expectations of the k-error linear complexity of a random sequence for k ≤ 3. Moreover, we study the 2t-error linear complexity of the set of 2n-periodic binary sequences with some fixed linear complexity L, where t < n-1 and the Hamming weight of the binary representation of 2n-L is t. Also, we extend some results to pn-periodic sequences over Fp. Finally, we discuss some potential applications.

Now that the subject of green computing is receiving a lot of attention, the energy consumption of datacenters has emerged as a significant issue. Consolidation of Virtual Machines (VMs) reduces the energy consumption since VM live migration not only optimizes VM placement, but also switches idle nodes to sleep mode. However, VM migration may negatively impact the performance of the system and lead to violations in SLA (Service Level Agreement) requirements between end users and cloud providers. In this study, we propose a VM consolidation mechanism that reduces the energy consumption of datacenters, eliminates unnecessary migrations, and minimizes the SLA violations. Compared to previous studies, the proposed policy shows a reduction of 2% to 3% in energy consumption, 13% to 41% in VM migration frequency, and 15% to 50% in SLA violations.

This paper proposes a so called quasi-linear support vector machine (SVM), which is an SVM with a composite quasi-linear kernel. In the quasi-linear SVM model, the nonlinear separation hyperplane is approximated by multiple local linear models with interpolation. Instead of building multiple local SVM models separately, the quasi-linear SVM realizes the multi local linear model approach in the kernel level. That is, it is built exactly in the same way as a single SVM model, by composing a quasi-linear kernel. A guided partitioning method is proposed to obtain the local partitions for the composition of quasi-linear kernel function. Experiment results on artificial data and benchmark datasets show that the proposed method is effective and improves classification performances.

In LTE (Long Term Evolution)-Advanced system, a transparent MU-MIMO (Multi-User Multiple-Input Multiple Output) scheduling is basically considered, so the performance degradation in channel estimation may occur due to the unpredictable interference from co-scheduled layers. In order to detect and mitigate the interference, traditional binary hypothesis testing based interference detection method and iterative channel estimation method can be applied. However, there are two major problems. First, the binary hypothesis testing based interference detection is not suitable solution for LTE-Advanced system which has four dynamically changing interference hypotheses. Second, the conventional iterative operation does not guarantee sufficient performance gain with limited iteration time due to the estimation error in initial estimation stage. To overcome these problems, we introduce an enhanced iterative channel estimation method which considers simple matrix operation-based partial interference estimation. Based on the outcomes of the partial interference estimation, we can not only detect interference layers individually, but also partially eliminate the interference in initial channel estimation stage. Consequently, the proposed method can effectively mitigate the interference adaptively to the dynamically changing interference condition.

Cloud computing has rising as a new popular service paradigm with typical advantages as ease of use, unlimited resources and pay-as-you-go pricing model. Cloud resources are more flexible and cost-effective than private or colocation resources thus more suitable for storing the outdated backup data that are infrequently accessed by continuous data protection (CDP) systems. However, the cloud achieves low cost at the same time may slow down the recovery procedure due to its low bandwidth and high latency. In this paper, a novel block-level CDP system architecture: MYCDP is proposed to utilize cloud resources as the back-end storage. Unlike traditional delta-encoding based CDP approaches which should traverse all the dependent versions and decode the recovery point, MYCDP adopts data deduplication mechanism to eliminate data redundancy between all versions of all blocks, and constructs a version index for all versions of the protected storage, thus it can use a query-and-fetch process to recover version data. And with a specific version index data structure and a disk/memory hybrid cache module, MYCDP reduces the storage space consumption and data transfer between local and cloud. It also supports deletion of arbitrary versions without risk of invalidating some other versions. Experimental results demonstrate that MYCDP can achieve much lower cost than traditional local based CDP approaches, while remaining almost the same recovery speed with the local based deduplication approach for most recovery cases. Furthermore, MYCDP can obtain both faster recovery and lower cost than cloud based delta-encoding CDP approaches for any recovery points. And MYCDP gets more profits while protecting multiple systems together.

In recent years, computation offloading, through which applications on a mobile device can offload their computations onto more resource-rich clouds, has emerged as a promising technique to reduce battery consumption as well as augment the devices' limited computation and memory capabilities. In order for computation offloading to be energy-efficient, an accurate estimate of battery consumption is required to decide between local processing and computation offloading. In this paper, we propose a novel technique for estimating battery consumption without requiring detailed information about the mobile application's internal structure or its execution behavior. In our approach, the relationship is derived between variables that affect battery consumption (i.e., the input to the application, the transmitted data, and resource status) and the actual consumed energy from the application's past run history. We evaluated the performance of the proposed technique using two different types of mobile applications over different wireless network environments such as 3G, Wi-Fi, and LTE. The experimental results show that our technique can provide tolerable estimation accuracy and thus make correct decisions between local processing and computation offloading.

Coalition Structure Generation (CSG) is a main research issue in the domain of coalition games. A majority of existing works assume that the value of a coalition is independent of others in the coalition structure. Recently, there has been interest in a more realistic settings, where the value of a coalition is affected by the formation of other coalitions. This effect is known as externality. The focus of this paper is to make use of Maximum Satisfiability (MaxSAT) to solve the CSG problem where externalities may exist. In order to reduce the exponentially growing number of possible solutions in the CSG problem, we follow the previous works by representing the CSG problem as sets of rules in MC-nets (without externalities) and embedded MC-nets (with externalities). Specifically, enlightened by the previous MC-net-based algorithms exploiting the constraints among rule relations to solve the CSG problem, we encode such constraints into weighted partial MaxSAT (WPM) formulas. Experimental results demonstrate that an off-the-shelf MaxSAT solver achieves significant improvements compared to the previous algorithm for the same set of problem instances.

The main purpose of this paper is to apply the boundary integral equation (BIE) method to the analysis of spoof localized surface plasmons (spoof LSPs) excited in a perfectly conducting cylinder with longitudinal corrugations. Frequency domain BIE schemes based on electric field integral equation (EFIE), magnetic field integral equation (MFIE) and combined field integral equation (CFIE) formulations are used to solve two-dimensional electromagnetic (EM) problems of scattering from the cylinder illuminated by a transverse electric plane wave. In this approach effects of spoof LSPs are included in the secondary surface current and charge densities resulting from the interaction between the plane wave and the cylinder. Numerical results obtained with the BIE schemes are validated by comparison with that of a recently proposed modal solution based on the metamaterial approximation.