When debugging bugs, programmers often prepare test cases to reproduce buggy behaviours. However, for concurrent programs, test cases alone are typically insufficient to reproduce buggy behaviours, due to the nondeterminism of multi-threaded executions. In literature, various approaches have been proposed to reproduce buggy behaviours for concurrency bugs deterministically, but to the best of our knowledge, they are still limited. In particular, we have recognized three debugging scenarios from programming practice, but existing approaches can handle only one of the scenarios. In this paper, we propose a novel approach, called SPDebugger, that provides finer-grained thread controlling over test cases, programs under test, and even third party library code, to reproduce the predesigned thread execution schedule. The evaluation shows that SPDebugger handles more debugging scenarios than the state-of-the-art tool, called IMUnit, with similar human effort.

We propose a cache-aware method to accelerate texture-based volume rendering on a graphics processing unit (GPU) that is compatible with the compute unified device architecture. The proposed method extends a previous method such that it can maximize the average rendering performance while rotating the viewing direction around a volume. To realize this, the proposed method performs in-place rotation of volume data, which rearranges the order of voxels to allow consecutive threads (warps) to refer to voxels with the minimum access strides. Experiments indicate that the proposed method replaces the worst texture cache (TC) hit rate of 42% with the best TC hit rate of 93% for a 10243-voxel volume. Thus, the average frame rate increases by a factor of 1.6 in the proposed method compared with that in the previous method. Although the overhead of in-place rotation slightly decreases the frame rate from 2.0 frames per second (fps) to 1.9 fps, this slowdown occurs only with a few viewing directions.

Network servers and applications commonly use static IP addresses and communication ports, making themselves easy targets for network reconnaissances and attacks. Moving target defense (MTD) is an innovatory and promising proactive defense technique. In this paper, we develop a novel MTD mechanism, called Random Port and Address Hopping (RPAH). The goal of RPAH is to hide network servers and applications and resist network reconnaissances and attacks by constantly changing their IP addresses and ports. In order to enhance the unpredictability, RPAH integrates source identity, service identity and temporal parameter in the hopping to provide three hopping frequencies, i.e., source hopping, service hopping and temporal hopping. RPAH provides high unpredictability and the maximum hopping diversities by introducing port and address demultiplexing mechanism, and provides a convenient attack detection mechanism with which the messages from attackers using invalid or inactive addresses/ports will be conveniently detected and denied. Our experiments and evaluation on campus network and PlanetLab show that RPAH is effective in resisting various network reconnaissance and attack models such as network scanning and worm propagation, while introducing an acceptable operation overhead.

A floating-point multiplier with concurrent error detection capability by partial duplication is proposed. It uses a truncated multiplier for checking of the significand (mantissa) multiplication instead of full duplication. The proposed multiplier can detect any erroneous output with error larger than one unit in the last place (1 ulp) of the significand, which may be overlooked by residue checking. Its circuit area is smaller than that of a fully duplicated one. Area overhead of a single-precision multiplier is about 78% and that of a double-precision one is about 65%.

In this paper, we describe the fabrication of low leakage Superconductor/Insulator/Superconductor (SIS) junctions with a Nb/Al/AlOx/Al/Nb structure. In other words, an extra Al layer was added onto the top of the insulator in a conventional Nb/Al/AlOx/Nb junction. We measured the current and voltage (IV) characteristics of both the Nb/Al/AlOx/Al/Nb and Nb/Al/AlOx/Nb junctions at the temperature of liquid helium, and found that the sub-gap leakage current in the Nb/Al/AlOx/Al/Nb junctions was much lower than that of the Nb/Al/AlOx/Nb junctions. Our analysis of the IV characteristics indicates that the quality of the AlOx insulator used in the Nb/Al/AlOx/Al/Nb junction was close to ideal, while the insulator used in the Nb/Al/AlOx/Nb junction had possible defects. According to the scanning transmission electron microscope (STEM) images and energy-dispersive X-ray spectroscopy (EDX) analyses, it was evident that the Nb atoms diffused into the bottom electrode of the Nb/Al/AlOx/Nb junction, while a smaller number diffused into the bottom electrode of the Nb/Al/AlOx/Al/Nb junction. Therefore, we conclude that the extra Al layer effectively acted as a buffer layer that prevented the Nb atoms from diffusing into the insulator and bottom electrode. The presence of the top Al layer is expected to favorably improve the quality of junctions with a very high current density, and support the extension of the RF and IF bandwidths of SIS mixers.

This paper proposes secure regenerating codes that are composed of non-secure regenerating codes and a new all-or-nothing transform. Unlike the previous analysis of secure regenerating codes, the security of the proposed codes is analyzed in the sense of the indistinguishability. The advantage of the proposed codes is that the overhead caused by the security against eavesdropping is much less than that of previous secure regenerating codes. The security of the proposed codes against eavesdropping mainly depends on the new all-or-nothing transform.

An equivalent-circuit model is an effective tool for the analysis and design of metamaterials. This paper describes a systematic and theoretical method for the circuit modeling of meta-atoms. We focus on the structures of wired metallic spheres and propose a method for deriving a sophisticated equivalent circuit that has the same topology as the wires using the partial element equivalent circuit (PEEC) method. Our model contains the effect of external electromagnetic coupling: excitation by an external field modeled by voltage sources and radiation modeled by the radiation resistances for each mode. The equivalent-circuit model provides the characteristics of meta-atoms such as the resonant frequencies and the resonant modes induced by the current distribution in the wires by an external excitation. Although the model is obtained by a very coarse discretization, it provides a good agreement with an electromagnetic simulation.

In this paper, a printed elliptical monopole antenna for wideband circular polarization is proposed. The antenna's structure is asymmetric with regard to the microstrip line. The section of the ground plane that overlaps the elliptical patch is removed. With simulations, the relationship between the antenna's geometrical parameters and the antenna's axial ratio of circularly polarized wave is clarified. The operational principle for wideband circular polarization is explained by the simulated electric current distributions. The simulated and measured bandwidths of the 3dB-axial ratio with a 2-VSWR is approximately 88.4% (2.12GHz-5.47GHz) and 83.6% (2.20GHz-5.36GHz), respectively.

In this paper, we propose a method to find similar sentences based on language resources for building a parallel corpus between English and Korean from Wikipedia. We use a Wiki-dictionary consisted of document titles from the Wikipedia and bilingual example sentence pairs from Web dictionary instead of traditional machine readable dictionary. In this way, we perform similarity calculation between sentences using sequential matching of the language resources, and evaluate the extracted parallel sentences. In the experiments, the proposed parallel sentences extraction method finally shows 65.4% of F1-score.

With the popularization of Internet of things (IoT), the interaction between human and IoT has become a daily life. In this interaction, the objects of IoT usually require access to personal data, which are often sensitive. We propose a lightweight privacy-preserving model based on the trust evaluation that it can effectively protect privacy based on simple threshold detection. The key issue we address in this work is how to construct trust model so that non trusted objects were prevented from accessing private data. This work can be considered as a lightweight approach to access control for privacy-preservation. The main algorithm in the proposed model is a kind of dynamic self-adjusting trust evaluation mechanism that uses a combination of interaction information occurs between the human and the Internet of things, between the human and the human. According to the given threshold, the trust model can determine the data level of object access in the IoT. We have implemented a prototype of the proposed scheme, thereby demonstrating the feasibility of the proposed scheme on resource-constrained devices.

The mixer is a crucial circuit block in a WiMax system receiver. The performance of a mixer depends on three specifications: conversion gain, linearity and noise figure. Many mixers have been recently proposed for UWB and wideband systems; however, they either cannot achieve the high conversion gain required for a WiMAX system or they are prone to high power consumption. In this paper, a folded mixer with a high conversion gain is designed for a 2-11GHz WiMAX system and it can achieve a 20MHz IF output signal. From the simulation results, the proposed folded mixer achieves a conversion gain of 18.9 to 21.5dB for the full bandwidth. With a 0.2 to 4.4dBm IIP3, the NF is 13.5 to 17.6dB. The folded mixer is designed using TSMC 0.18µm CMOS technology. The core power consumption of the mixer is 11.8mW.

Advances in intelligent vehicle systems have led to modern automobiles being able to aid drivers with tasks such as lane following and automatic braking. Such automated driving tasks increasingly require reliable ego-localization. Although there is a large number of sensors that can be employed for this purpose, the use of a single camera still remains one of the most appealing, but also one of the most challenging. GPS localization in urban environments may not be reliable enough for automated driving systems, and various combinations of range sensors and inertial navigation systems are often too complex and expensive for a consumer setup. Therefore accurate localization with a single camera is a desirable goal. In this paper we propose a method for vehicle localization using images captured from a single vehicle-mounted camera and a pre-constructed database. Image feature points are extracted, but the calculation of camera poses is not required — instead we make use of the feature points' scale. For image feature-based localization methods, matching of many features against candidate database images is time consuming, and database sizes can become large. Therefore, here we propose a method that constructs a database with pre-matched features of known good scale stability. This limits the number of unused and incorrectly matched features, and allows recording of the database scales into “tracklets”. These “Feature scale tracklets” are used for fast image match voting based on scale comparison with corresponding query image features. This process reduces the number of image-to-image matching iterations that need to be performed while improving the localization stability. We also present an analysis of the system performance using a dataset with high accuracy ground truth. We demonstrate robust vehicle positioning even in challenging lane change and real traffic situations.

In this letter, we propose a novel speech separation method based on perceptual weighted deep recurrent neural network (DRNN) which incorporate the masking properties of the human auditory system. In supervised training stage, we firstly utilize the clean label speech of two different speakers to calculate two perceptual weighting matrices. Then, the obtained different perceptual weighting matrices are utilized to adjust the mean squared error between the network outputs and the reference features of both the two clean speech so that the two different speech can mask each other. Experimental results on TSP speech corpus demonstrate that the proposed speech separation approach can achieve significant improvements over the state-of-the-art methods when tested with different mixing cases.

We prepared a bR thin film by the wire-bar coating technique, and investigated the transient photo-current characteristics of the bR photocell. The transient photo-current signal of bR photocells prepared by the wire-bar coating technique and the dip coating technique was compared. An almost identical transient photo-current signal intensity was obtained both for the wire-bar coating technique and dip coating technique, while the thickness of bR thin film prepared by the wire-bar coating technique is slightly thinner than that prepared by the dip-coating technique. Transparent conductive oxide dependence of the transient photo-current signal is almost the same dependence for the bR photocells with a bR thin film prepared by both techniques. Application of the wire-bar coating technique is significant from the viewpoints of the bR's sample consumption as well as simplicity of sample preparation.

Driving safety related innovations received increasing interest from automotive industry. We performed an experiment to observe what situations are related to the secured feelings drivers feel when they drive, and found out that drivers need to have four to seven seconds to react possible collision when they operate onboard Human Machine Interface (HMI) devices and check display devices. We explored the distance of semantic space to see what factors of HMI interaction lead to the secured feeling in that time period, and extracted 32 types of factors that lead to the secured feelings. Furthermore, in the process of investigating the semantic space distance, the indicators relating to the secured feelings obtained in the prior studies were further determined to be ‘The layout of the operation device is the same as the driver's image' and ‘The driver can use the word he uses every day to give instructions’ in this time period.’, which were more concrete factors of the secured feelings.

Establishing drivers' trust in the automated driving system is critical to the success of automated vehicles. The focus of this paper is learning what drivers of automated vehicles need to feel confident during braking events. In this study, 10 participants drove a test vehicle and each experienced 24 different deceleration settings. Prior to each drive, it was indicated to each participant what the expected brake starting and stopping positions would be. During each drive, participants maintained a set speed, and then stopped the vehicle when they saw a signal to apply the brakes. After each drive, the participants were asked what their perceived safety level was during the deceleration setting they just experienced. The results revealed that ‘jerk’ movements have significant influence on drivers' perceived safety. For this study, we have named this jerk movement impression jerk (IJ). Using IJ, clearly divides the secure and anxious feelings of the drivers along with individual differences.

In order to prevent the synonym substitution breaking the balance among frequencies of synonyms and improve the statistical undetectability, this paper proposed a novel linguistic steganography based on synonym run-length encoding. Firstly, taking the relative word frequency into account, the synonyms appeared in the text are digitized into binary values and expressed in the form of runs. Then, message are embedded into the parities of runs' lengths by self-adaptively making a positive or negative synonym transformation on boundary elements of two adjacent runs, while preserving the number of relative high and low frequency synonyms to reduce the embedding distortion. Experimental results have shown that the proposed synonym run-length encoding based linguistic steganographic algorithm makes fewer changes on the statistical characteristics of cover texts than other algorithms, and enhances the capability of anti-steganalysis.

Controlling synchrony as well as desynchrony in a network of neuronal oscillators has been one of the focus issues in nonlinear science and engineering. It has been well known that spike stimuli injected commonly to multiple neurons can synchronize them if the strength of the common spike stimuli is high enough. Our recent study showed that this common spike-induced synchrony could be suppressed by introducing heterogeneity to inhibitory connections, through which the common spikes are transmitted. The aim of the present study is apply this methodology to electronic neurons as a real physical hardware. Using an Axon-Hillock circuit that represents basic properties of the leaky integrate-and-fire (LIF) neuron, our experiment demonstrated that the method was quite effective for desynchronizing the neuron circuits. The experimental results are also in a good agreement with the linear response theory that describes the input-output relationship of LIF neurons. Our method of suppressing the neuronal synchrony should be of practical use for enhancement of neural information processing as well as for improvement of pathological state of the brain.

In this paper, a hardware efficient design methodology for a configurable-point multiple-stream pipeline FFT processor is presented. We first compared the memory and arithmetic components of different pipeline FFT architectures, and obtained the conclusion that MDF architecture is more hardware efficient than MDC for the overall processor. Then, in order to reduce the computational complexity, a binary-tree representation was adopted to analyze the decomposition algorithm. Consequently, the coefficient multiplications are minimized among all the decomposition probabilities. In addition, an efficient output reorder circuit was designed for the multiple-stream architecture. An 128∼2048 point 4-stream FFT processor in LTE system was designed in SMIC 55nm technology for evaluation. It owns 1.09mm2 core area with 82.6mW power consumption at 122.88MHz clock frequency.

Anonymous password-based authentication protocols are designed to provide not only password-based authentication but also client anonymity. In [22], Qian et al. proposed a simple anonymous password-based authentication protocol (SAPAKE). In this paper, we reconsider the SAPAKE protocol [22] by first showing that an (third party) active attacker can impersonate the server and compute a session key with probability 1. After giving a formal model that captures such attacks, we propose a simple and secure anonymous password-based authentication (for short, S2APA) protocol that provides security against modification attacks on protocol-specific values and is more efficient than YZWB09/10 [32], [33] and SAPAKE [22]. Also, we prove that the S2APA protocol is AKE-secure against active attacks as well as modification attacks under the computational Diffie-Hellman problem in the random oracle model, and provides unconditional client anonymity against a semi-honest server, who honestly follows the protocol.