3,836 research outputs found

    Generalized Signal Alignment For MIMO Two-Way X Relay Channels

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    We study the degrees of freedom (DoF) of MIMO two-way X relay channels. Previous work studied the case N<2MN < 2M, where NN and MM denote the number of antennas at the relay and each source, respectively, and showed that the maximum DoF of 2N2N is achievable when Nβ‰€βŒŠ8M5βŒ‹N \leq \lfloor\frac{8M}{5}\rfloor by applying signal alignment (SA) for network coding and interference cancelation. This work considers the case N>2MN>2M where the performance is limited by the number of antennas at each source node and conventional SA is not feasible. We propose a \textit{generalized signal alignment} (GSA) based transmission scheme. The key is to let the signals to be exchanged between every source node align in a transformed subspace, rather than the direct subspace, at the relay so as to form network-coded signals. This is realized by jointly designing the precoding matrices at all source nodes and the processing matrix at the relay. Moreover, the aligned subspaces are orthogonal to each other. By applying the GSA, we show that the DoF upper bound 4M4M is achievable when Mβ‰€βŒŠ2N5βŒ‹M \leq \lfloor\frac{2N}{5}\rfloor (MM is even) or Mβ‰€βŒŠ2Nβˆ’15βŒ‹M \leq \lfloor\frac{2N-1}{5}\rfloor (MM is odd). Numerical results also demonstrate that our proposed transmission scheme is feasible and effective.Comment: 6 pages, 6 figures, to appear in IEEE ICC 201

    Rotation-invariant features for multi-oriented text detection in natural images.

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    Texts in natural scenes carry rich semantic information, which can be used to assist a wide range of applications, such as object recognition, image/video retrieval, mapping/navigation, and human computer interaction. However, most existing systems are designed to detect and recognize horizontal (or near-horizontal) texts. Due to the increasing popularity of mobile-computing devices and applications, detecting texts of varying orientations from natural images under less controlled conditions has become an important but challenging task. In this paper, we propose a new algorithm to detect texts of varying orientations. Our algorithm is based on a two-level classification scheme and two sets of features specially designed for capturing the intrinsic characteristics of texts. To better evaluate the proposed method and compare it with the competing algorithms, we generate a comprehensive dataset with various types of texts in diverse real-world scenes. We also propose a new evaluation protocol, which is more suitable for benchmarking algorithms for detecting texts in varying orientations. Experiments on benchmark datasets demonstrate that our system compares favorably with the state-of-the-art algorithms when handling horizontal texts and achieves significantly enhanced performance on variant texts in complex natural scenes

    Production of biscuits by substitution with different ratios of yellow pea flour

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    To promote the commercialization of yellow pea flour (YPF) due to its nutritional benefits. Four biscuits with different YPF ratio (10%–50%) were conducted to explore the optimal addition percentage. The effects of YPF on the rheological and baking performance of biscuits were performed. The results showed that the substitution ratio of YPF and milling methods had a critical impact on the rheological properties of dough. The dough stability decreased gradually while a softening degree increased with YPF ratio increased. In a term of biscuits, the dimensions of length (L), width (W), thickness (T) and color (L*) of biscuits reduced as YPF addition ratio increased, while colors (a* and b*) and hardness apparently increased. In addition, milling methods had a great influence on the texture and sensory evaluation of four biscuits. The dimensions and color parameters of biscuits from fine flours were larger than that from coarse flours, whereas hardness from fine flours was relatively softer, indicating flour with fine particle size could accelerate the extension and expansion of dough network, and improve Maillard reaction during baking. The highest sensory score for short and tough biscuits was obtained given at YPF ratio of 30% without compromising the qualities of biscuits
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