Coded cooperative spatial modulation based on multi-level construction of polar code

Telecommunication Systems - A spatial modulation scheme based on the multi-level construction of polar code is proposed and its performance over Rayleigh and Rician fading channels is evaluated....     

Distributed Polar Coded Single Carrier-FDMA Based on Multilevel Construction Over Multipath Channels

Wireless Personal Communications - A multilevel constructed polar coded single carrier frequency division multiple access (MLPC-SCFDMA) scheme is proposed and its bit-error rate performance over...     

Estimating layout of cluttered indoor scenes using trajectory-based priors

Given a surveillance video of a moving person, we present a novel method of estimating layout of a cluttered indoor scene. We propose an idea that trajectories of a moving person can be used to generate features to segment an indoor scene into different areas of interest. We assume a static uncalibrated camera. Using pixel-level color and perspective cues of the scene, each pixel is assigned to a particular class either a sitting place, the ground floor, or the static background areas like walls and ceiling. The pixel-level cues are locally integrated along global topological order of classes, such as sitting objects and background areas are above ground floor into a conditional random field by an ordering constraint. The proposed method yields very accurate segmentation results on challenging real world scenes. We focus on videos with people walking in the scene and show the effectiveness of our approach through quantitative and qualitative results. The proposed estimation method shows better estimation results as compared to the state of the art scene layout estimation methods. We are able to correctly segment 90.3% of background, 89.4% of sitting areas and 74.7% of the ground floor.     

A novel countermeasure technique for reactive jamming attack in internet of things

Multimedia Tools and Applications - In recent years, Internet of Things (IoT) has attracted significant attention because of its wide range of applications in various domains. However, security is...     

Intercomparison of Terahertz Dielectric Measurements Using Vector Network Analyzer and Time-Domain Spectrometer

We describe a method for direct intercomparison of terahertz permittivities at 200 GHz obtained by a Vector Network Analyzer and a Time-Domain Spectrometer, whereby both instruments operate in their customary configurations, i.e., the VNA in waveguide and TDS in free-space. The method employs material that can be inserted into a waveguide for VNA measurements or contained in a cell for TDS measurements. The intercomparison experiments were performed using two materials: petroleum jelly and a mixture of petroleum jelly with carbon powder. The obtained values of complex permittivities were similar within the measurement uncertainty. An intercomparison between VNA and TDS measurements is of importance because the two modalities are customarily employed separately and require different approaches. Since material permittivities can and have been measured using either platform, it is necessary to ascertain that the obtained data is similar in both cases.     

Electrical resistivity and flexural strength of mullite-bonded porous SiC: Effect of transition metal additives

The influence of various transition metal (Mo, Co, Ni, and Fe) additives on the electrical and mechanical properties of mullite-strengthened SiC sintered in the range of 1100–1500°C under an Ar atmosphere was investigated. Kaolin was added as a low-temperature sintering aid in the designed formulations. The addition of metal additives reduced the electrical resistivity, enhanced the mechanical strength, and produced samples with an approximately 40% porosity. The decrease in electrical resistivity was attributed to the in situ formation of electrically conductive metal silicides, whereas the conversion of kaolin to mullite enhanced the mechanical properties. The comparative study shows that at the same metal-additive content (15 wt%), Fe was the most effective element to reduce the electrical resistivity and increase the flexural strength, which were recorded as 8.0 × 10⁰ Ω cm and 20 ± 2 MPa, respectively, of the samples sintered at merely 1300°C.     

Graphite Filler-Based Nanocomposites with Thermoplastic Polymers: A Review

This up-to-date review comprehends the research performed on three important types of thermoplastic polymers, i.e., polyamide, polyimide, and poly(amide-imide). Graphite has been discussed as indispensable nanofiller to form significant categories of polyamide/graphite, polyimide/graphite, and poly(amide-imide)/graphite nanocomposite. Main focus of this review was to outline the properties and potential of these polymers and their composites. Studies have demonstrated considerable enhancement in the strength, thermal, electrical, rheology, and wear properties of these polymers upon graphite addition. Significance of polyamide, polyimide, poly(amide-imide), and graphite-based composites have been discussed keeping in view the challenges and future demands for contemporary technical applications.     

Thermal management of newly developed non-noble metal-based catalytic converter to reduce cold start emissions of small internal combustion engine

In this study, thermal management of a newly developed non-noble metal-based catalytic converter, more suitable to smaller engines, has been investigated. Two different approaches are explored; first, use of phase change material (PCM) to keep the converter hot beyond light off temperature during shorter soak times and second, electrically heating up converter before or after engine cold start-up to reduce cold start emissions. The converter used had light off temperatures of 195 and 206°C for carbon monoxide and hydro carbons, respectively. Results showed that 1?kg of PCM was capable of keeping the converter hot beyond light off temperatures for a soak time of 2.5?h. Similarly, use of glow plugs also decreased the light off time of the converter to less than 2?min as compared to 13?min without thermal management measures.