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Figure 1: Comparison of traditional text-based image retrieval, conventional SBIR, and the proposed fine-grained SBIR framework.Introduction Sketches are known to be able to capture object appearance and structure more intuitively and precisely than bare texts. However, to date the main focus of sketch-based image retrieval (SBIR) has been on retrieving photos of the same category, overlooking an important property of sketches -they can capture fine-grained variations of objects such as pose (standing vs. sitting) and iconic pattern (textures on a cow's body). By further leveraging this descriptive power of sketches, in this paper, for the first time we introduce fine-grained SBIR. That is to study how sketches can be used to differentiate fine-grained variations of objects for retrieval, specifically pose variations. Figure 1 contrasts text-based image retrieval and conventional SBIR with our proposed fine-grained SBIR. Methodology Key to this problem is introducing a mid-level sketch representation that not only captures object pose, but also possesses the ability to traverse sketch and photo domains. Specifically, we learn deformable part-based model (DPM) [3] to discover and encode the various poses and parts in sketch and image domains independently, and employ graph matching [1] to establishing the correspondence between DPMs from different domains. The DPM is a two-layer structure, composed of root filter and part filters. We denote DPM as M = (r, G), where r = (w, h, f ) specifies the width w, height h and global appearance feature of the root filter; and G = (V, E, A) represents the star graph composed of the part filters. For the star graph G, V represents a set of nodes, E, edges, and A, attributes. Our matching objective for DPM accounts for both appearance and geometric information encoded in DPM, as well as both layers of representation, i.e., root filter r and part filter star graph G. Given two DPMs M R and M T , the similarity function is defined as:

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A total synthesis of the novel sesquiterpene anthecularin 1, isolated from Greek Anthemis auriculata, based on an intramolecular [5+2] (1,3-dipolar) cycloaddition involving the oxidopyrylium ion 12 derived from the furanmethanol 9, is described.

This article presents semiparametric joint models to analyze longitudinal measurements and survival data with a cure fraction. We consider a broad class of transformations for the cure-survival model, which includes the popular proportional hazards structure and the proportional odds structure as special cases. We propose to estimate all the parameters using the nonparametric maximum likelihood estimators (NPMLE). We provide the simple and efficient EM algorithms to implement the proposed inference procedure. Asymptotic properties of the estimators are shown to be asymptotically normal and semiparametrically efficient. Finally, we demonstrate the good performance of the method through extensive simulation studies and a real-data application.

This paper presents the experimental and numerical investigation on resistance of two-storey steel sub-frames subjected to a middle column removal scenario. Two different types of 1/2 scaled steel sub-frames with seismic configuration were fabricated and tested, they are: (1) welded connections with gross beam section (GBS) and (2) welded connections with reduced beam section (RBS, typically used for energy dissipation in earthquake design). Based on the test results, finite element models using explicit software LS-DYNA which can accurately replicate the response of the frames were created and validated. Using the validated model, the parametric studies were also performed to investigate the effect of different parameters on the progressive collapse resistance of the frame. Base on the experimental and numerical studies, the failure mechanism and collapse resistance capacities of these two types of frame systems are first time investigated. The test results indicated that the welded connections with RBS exhibits better performance due to the guaranteed formation of plastic hinges at the location of reduced section, as well as the avoidance of welding heat effect and brittle weld fracture at beam to column connections. Thus, RBS exhibits larger deformation capacity which is favorable in mitigating the possible progressive collapse.

The supervised single‐channel speech enhancement presents one mixture recording at the input of the neural network and updates network parameters in order to generate an output as the reconstructed speech signal. However, current neural networks‐based single‐channel speech enhancement methods are not able to fully utilise pertinence with the specific frequency range of speech signals with limited computational complexity. In this study, the authors studied the power spectral density of mixtures with human speech and noise interferences. Based on the theory that the speech signal distributes at the lower band, they proposed a method to train signal approximation (SA) based neural networks with the lower frequency band of the speech mixture to improve the performance. To realise the lower band approach for single‐channel speech enhancement, the method uses a long short‐term memory (LSTM) block to exploit short‐time Fourier transform of the desired frequency range. Furthermore, in order to improve the speech enhancement performance within reverberant room environments, the dereverberation mask and the enhanced ratio mask are exploited as the training targets of two LSTM blocks, respectively. The detailed evaluations confirm that the proposed method outperforms the state‐of‐the‐art methods.

Irregular needling embroidery has a very high artistic value as a Changzhou craftwork. Artists use stitches of rich colors and apply different types of stitch categories from course to fine on multiple layers to express objects. This paper proposes an irregular needling embroidery rendering method based on image. We first decompose the image into different regions, vector fields and image detail information to guild the subsequent simulation process. Then we hierarchically render the image with a series of layers and propose a multilayer rendering technique. Additionally, we build a stitch dictionary and present a method to simulate the threads. Experimental results demonstrate that the method proposed in this paper transfers reference images quickly and efficiently into their irregular needling embroidery simulations.