The sense of presence, that is, the sense of the website being psychologically transported to the consumer, has been identified as an important factor for bringing back the feeling of sociability and physicality that is lost in online shopping. Previous research has investigated how visual content in the design can influence the sense of presence in a website, but the focus has been limited to the domestic electronic commerce context. In this paper, we conduct an experimental study in a cross-border electronic commerce context to evaluate the effect of country-related pictures on the perception of country presence, visual appeal and trust in a foreign online store. Two experimental conditions were considered: country-related pictures and generic pictures, each one evaluated for Thai and Singaporean websites. It was hypothesized that country-related content in pictures included in the design of the foreign online store would result in a higher level of country presence, and that this would in turn result in higher visual appeal and trust in the website. We conducted a survey among Japanese online consumers, with a total of 1991 participants obtained. The subjects were randomly assigned into four groups corresponding to the combination of country-of-origin of the website and picture condition. We used structural equation modeling in order to analyze the proposed hypotheses. The results showed that for both the Thai and Singaporean websites, country-related pictures resulted in higher country presence, and visual appeal was positively influenced by this increase in country presence. However, country presence did not have a direct effect on trust; this effect was completely mediated by visual appeal. We discuss these results and their implications for cross-border electronic commerce.

We propose an effective technique for estimation of targets by ground penetrating radar (GPR) using model-based compressive sensing (CS). We demonstrate the technique's performance by applying it to detection of buried landmines. The conventional CS algorithm enables the reconstruction of sparse subsurface images using much reduced measurement by exploiting its sparsity. However, for landmine detection purposes, CS faces some challenges because the landmine is not exactly a point target and also faces high level clutter from the propagation in the medium. By exploiting the physical characteristics of the landmine using model-based CS, the probability of landmine detection can be increased. Using a small pixel size, the landmine reflection in the image is represented by several pixels grouped in a three dimensional plane. This block structure can be used in the model based CS processing for imaging the buried landmine. The evaluation using laboratory data and datasets obtained from an actual mine field in Cambodia shows that the model-based CS gives better reconstruction of landmine images than conventional CS.

The sense of presence is often used to evaluate the performances of audio-visual (AV) content and systems. However, a presence meter has yet to be realized. We consider that the sense of presence can be divided into two aspects: system presence and content presence. In this study we focused on content presence. To estimate the overall presence of a content item, we have developed estimation models for the sense of presence in audio-only and audio-visual content. In this study, the audio-visual model is expanded to estimate the instantaneous presence in an AV content item. Initially, we conducted an evaluation experiment of the presence with 40 content items to investigate the relationship between the features of the AV content and the instantaneous presence. Based on the experimental data, a neural-network-based model was developed by expanding the previous model. To express the variation in instantaneous presence, 6 audio-related features and 14 visual-related features, which are extracted from the content items in 500-ms intervals, are used as inputs for the model. The audio-related features are loudness, sharpness, roughness, dynamic range and standard deviation in sound pressure levels, and movement of sound images. The visual-related features involve hue, lightness, saturation, and movement of visual images. After constructing the model, a generalization test confirmed that the model is sufficiently accurate to estimate the instantaneous presence. Hence, the model should contribute to the development of a presence meter.

This work presents an approximate global optimization method for image halftone by fusing multi-scale information of the tree model. We employ Gaussian mixture model and hidden Markov tree to characterized the intra-scale clustering and inter-scale persistence properties of the detailed coefficients, respectively. The model of multiscale perceived error metric and the theory of scale-related perceived error metric are used to fuse the statistical distribution of the error metric of the scale of clustering and cross-scale persistence. An Energy function is then generated. Through energy minimization via graph cuts, we gain the halftone image. In the related experiment, we demonstrate the superior performance of this new algorithm when compared with several algorithms and quantitative evaluation.

A high frequency approximation method is proposed to obtain the scattering from rectangular dielectric cuboids. Our formulation is based on a Kirchhoff type aperture integration of the equivalent current sources over the surface of the scattering bodies. The derived formulae have been used to get the radar cross section of cuboids, and the results are compared with those by other methods, such as physical optics, geometrical theory of diffraction, the HFSS simulation and measurements. Good agreement has been observed to confirm the validity of our method.

It has been reported that a left-handed waveguide can be constituted using cutoff TE10 mode of rectangular waveguide. Because the cutoff TE10 mode shows effectively negative permittivity, the left-handed mode propagates by adding series capacitance in the form of short- or open-stubs. This paper suggests a constitution method of left-handed waveguides using cutoff TM mode. In this case, the cutoff TM mode shows effectively negative permeability. Therefore, a left-handed waveguide can be constituted by adding parallel inductance. In this paper, two types of the left-handed waveguides are designed using circular TM01 mode and rectangular TM11 mode, and the dispersion characteristics are numerically investigated. The validity of the constituting principle is confirmed by an experiment.

The ordered successive interference cancellation (OSIC) detector based on the minimum mean square error (MMSE) criterion has been proved to be a low-complexity detector with efficient bit error rate (BER) performance. As the well-known MMSE-Based OSIC detector, the MMSE-Based vertical Bell Laboratories Layered Space-Time (VBLAST) detector, whose computational complexity is cubic, can not attain the minimum BER performance. Some approaches to reducing the BER of the MMSE-Based VBLAST detector have been contributed, however these improvements have large computational complexity. In this paper, a low complexity MMSE-Based OSIC detector called MMSE-OBEP (ordering based on error probability) is proposed to improve the BER performance of the previous MMSE-Based OSIC detectors, and it has cubic complexity. The proposed detector derives the near-exact error probability of the symbols in the MMSE-Based OSIC detector, thus giving priority to detect the symbol with the smallest error probability can minimize the error propagation in the MMSE-Based OSIC detector and enhance the BER performance. We show that, although the computational complexity of the proposed detector is cubic, it can provide better BER performance than the previous MMSE-Based OSIC detector.

This paper deals with the security of chaos-based “true” random number generators (RNG)s. An attack method is proposed to analyze the security weaknesses of chaos-based RNGs and its convergence is proved using a master slave synchronization scheme. Attack on a RNG based on a double-scroll attractor is also presented as an example. All secret parameters of the RNG are revealed where the only information available is the structure of the RNG and a scalar time series observed from the double-scroll attractor. Simulation and numerical results of the proposed attack method are given such that the RNG doesn't fulfill NIST-800-22 statistical test suite, not only the next bit but also the same output bit stream of the RNG can be reproduced.

This paper proposes the first (practical) inner product encryption (IPE) scheme that is adaptively secure and fully attribute-hiding (attribute-hiding in the sense of the definition by Katz, Sahai and Waters), while the existing (practical) IPE schemes are either fully attribute-hiding but selectively secure or adaptively secure but weakly attribute-hiding. The proposed IPE scheme is proven to be adaptively secure and fully attribute-hiding under the decisional linear assumption in the standard model. The IPE scheme is comparably as efficient as the existing (practical) attribute-hiding IPE schemes. We also present a variant of the proposed IPE scheme with the same security that achieves shorter public and secret keys. A hierarchical IPE scheme can be constructed that is also adaptively secure and fully attribute-hiding under the same assumption. In this paper, we extend the dual system encryption technique by Waters into a more general manner, in which new forms of ciphertext and secret keys are employed and new types of information theoretical tricks are introduced along with several forms of computational reduction.

In this letter, we propose a blind adaptive algorithm for joint compensation of inter-block interference (IBI) and frequency-dependent IQ imbalance using a single time-domain equalizer. We combine the MERRY algorithm for IBI suppression with the differential constant modulus algorithm to compensate for IQ imbalance. The effectiveness of the proposed algorithm is shown through computer simulations.

Remote Access Trojans (RAT) is a spyware which can steal the confidential information from a target organization. The detection of RATs becomes more and more difficult because of targeted attacks, since the victim usually cannot realize that he/she is being attacked. After RAT's intrusion, the attacker can monitor and control the victim's PC remotely, to wait for an opportunity to steal the confidential information. As this situation, the main issue we face now is how to prevent confidential information being leaked back to the attacker. Although there are many existing approaches about RAT detection, there still remain two challenges: to detect RAT sessions as early as possible, and to distinguish them from the normal applications with a high accuracy. In this paper, we propose a novel approach to detect RAT sessions by their network behavior during the early stage of communication. The early stage is defined as a short period of time at communication's beginning; it also can be seen as the preparation period of the communication. We extract network behavior features from this period, to differentiate RAT sessions and normal sessions. For the implementation and evaluation, we use machine learning techniques with 5 algorithms and K-Fold cross-validation. As the results, our approach could detect RAT sessions in the communication's early stage with the accuracy over 96% together with the FNR of 10% by Random Forest algorithm.

The increasing demand for navigation and automation has led to the development of a number of accurate and precise navigation applications that make use of the Global Navigation Satellite System (GNSS) and additional sensors. One of the precise navigation techniques in GNSS, the real-time kinematic (RTK) technique, is well known. In this method, once the correct integer ambiguities are found in the carrier phase observation data, position can be determined to within 10cm. In particular, the advent of QZSS and BeiDou satellites can increase the availability of RTK-GNSS (relative to RTK using only GPS). It is understood that the increasing availability of RTK-GNSS will improve the performance of the integration of GNSS with additional sensors because the errors due to the inertial measurement unit (IMU) accumulate as time goes on. On the other hand, GNSS tends to suffer from multipath errors, especially in urban environments. To overcome this problem, a method was developed for improving RTK-GNSS using a low-cost IMU and conventional vehicle speed sensors. In this study, the quality of the complete observation data was assessed based on the carrier-to-noise ratio and satellite elevation angle, and the least-squares ambiguity decorrelation adjustment method and the ratio test were used to obtain fixed positions. We used speed information obtained from Doppler measurements as an alternative source of information; information from the IMU and vehicle speed sensor (integrated with the RTK-GNSS via a Kalman Filter) was used when there were no visible satellites. We also used the IMU and vehicle speed sensors to detect wrong fixes in the RTK-GNSS. A position and orientation system for land vehicles (Applanix) was used to estimate the reference positions. During GNSS outages, it is important to accurately determine the last heading of the car for precise navigation. In this study, it was found that GNSS Doppler-based direction data are required to obtain better direction information. The results of the experiment demonstrate that our proposed method is, to some extent, beneficial as an alternative to the conventional RTK-GPS in an urban environment.

A novel directional coupler loaded with feedback capacitances on the coupled lines is presented. Its effect of enhancing the coupling is qualitatively shown by deriving an equation for the coupling. Besides, a method to compensate for the phase difference between the even and odd modes of the coupler is presented. To demonstrate, a novel tandem 3-dB coupler consisting of the proposed coupled lines is designed and described. In addition, a waveguide (rectangular coaxial line) 8×8 HYB matrix using planar double-layer structure that is composed of the proposed tandem 3-dB couplers and branch-line couplers, which is operated in S-band, is designed and fabricated showing excellent performance.

This paper describes a hierarchical and cooperative transport system with demand responsive buses to improve service quality of public transport system in city area and its suburbs. To provide the demand responsive buses generally requires planning route and schedule called dial-a-ride problem. However, the problem complexity increases with the increasing of the number of requests. Therefore, we propose the hierarchical and cooperative transport system. Framework of the system can reduce scale of the problem by grouping customers. We have evaluated the proposed system on a static simulation and a dynamic microscopic simulation. The simulation result has shown the system could improve service quality by reducing customer's load. Moreover, the result of the dynamic simulation have provided the detailed features of the system.

The phenomenon of stochastic resonance (SR) in a mono-threshold-system-based detector (MTD) with additive background noise and multiplicative external noise is investigated. On the basis of maximum a posteriori probability (MAP) criterion, we deal with the binary signal transmission in four scenarios. The performance of the MTD is characterized by the probability of error detection, and the effects of system threshold and noise intensity on detectability are discussed in this paper. Similar to prior studies that focus on additive noises, along with increases in noise intensity, we also observe a non-monotone phenomenon in the multiplicative ways. However, unlike the case with the additive noise, optimal multiplicative noises all tend toward infinity for fixed additive noise intensities. The results of our model are potentially useful for the design of a sensor network and can help one to understand the biological mechanism of synaptic transmission.

The sliding discrete Fourier transform (DFT) is a well-known algorithm for obtaining a few frequency components of the DFT spectrum with a low computational cost. However, the conventional sliding DFT cannot be applied to practical conditions, e.g., using the sine window and the zero-padding DFT, with preserving the computational efficiency. This paper discusses the extension of the sliding DFT to such cases. Expressing the window function by complex sinusoids, a recursive algorithm for computing a frequency component of the DFT spectrum using an arbitrary sinusoidal window function is derived. The algorithm can be easily extended to the zero-padding DFT. Computer simulations using very long signals show the validity of our algorithm.

Two spanning trees T1,T2 of a graph G = (V,E) are independent if they are rooted at the same vertex, say r, and for each vertex v ∈ V, the path from r to v in T1 and the path from r to v in T2 have no common vertices and no common edges except for r and v. In general, spanning trees T1,T2,…,Tk of a graph G = (V,E) are independent if they are pairwise independent. A graph G = (V,E) is called a 2-chordal ring and denoted by CR(N,d1,d2), if V = {0,1,…,N-1} and E = {(u,v)|[v-u]N = 1 or [v-u]N = d1 or [v-u]N = d2, 2 ≤ d1 < d2 ≤ N/2}. CR(N,d1,N/2) is 5-connected if N ≥ 8 is even and d1 ≠ N/2-1. We give an algorithm to construct 5 independent spanning trees of CR(N,d1,N/2),N ≥ 8 is even and 2 ≤ d1 ≤ ⌈N/4⌉.

This letter proposes a situation-adaptive detection algorithm for the improved efficiency of the detection performance and complexity in the MIMO-OFDM system. The proposed algorithm adaptively uses the QRD-M, DFE, and iterative detection scheme in according to the detection environment. Especially, the proposed algorithm effectively reduces the occurrence probability of error in the successive interference cancellation procedure by the unit of the spatial stream. The simulations demonstrate that the adaptive detection method using the proposed algorithm provides a better trade-off between detection performance and complexity in the MIMO-OFDM system.