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Image colorization is a classic and important topic in computer graphics, where the aim is to add color to a monochromatic input image to produce a colorful result. In this survey, we present the history of colorization research in chronological order and summarize popular algorithms in this field. Early works on colorization mostly focused on developing techniques to improve the colorization quality. In the last few years, researchers have considered more possibilities such as combining colorization with NLP (natural language processing) and focused more on industrial applications. To better control the color, various types of color control are designed, such as providing reference images or color-scribbles. We have created a taxonomy of the colorization methods according to the input type, divided into grayscale, sketch-based and hybrid. The pros and cons are discussed for each algorithm, and they are compared according to their main characteristics. Finally, we discuss how deep learning, and in particular Generative Adversarial Networks (GANs), has changed this field.

Non-rigid registration of deformed 3D shapes is a challenging and fundamental task in geometric processing, which aims to non-rigidly deform a source shape into alignment with a target shape. Current state-of-the-art methods assume deformations to be near-isometric. This assumption does not reflect real-world conditions, for example in large-scale deformation, where moderate anisotropic deformations (e.g., stretches) are common. In this paper we propose two significant changes to a typical registration pipeline to address such challenging deformations. First, we introduce a method to estimate anisotropic non-isometric deformations and incorporate this into an iterative non-rigid registration pipeline. Second, we compute additional correspondences in non-isometrically deforming regions using reliable correspondences as landmarks and prune inconsistent correspondences. We compare the performance of our proposed algorithm to several state-of-the-art methods using existing benchmarks. Experimental results show that our method outperforms existing methods.

Atherosclerosis is the main cause of many cardiovascular diseases. Endothelial dysfunction is recognized as an early event in the development of atherosclerosis. Many drugs have been studied to mitigate hyperlipidemia-induced endothelial injury. Studies have demonstrated that neuropeptide substance P (SP) and its preferred receptor neurokinin receptor 1 (NK-1R) are involved in the pathological progression of cardiovascular disease. In this study, we show that aprepitant, a selective NK-1R antagonist, possesses beneficial effects that protect endothelial cells from oxidized low-density lipoprotein (ox-LDL)-induced inflammatory response and injury. Our data demonstrate that NK-1R is expressed in both aortic and vein-originated endothelial cells and that ox-LDL treatment induces NK-1R expression. Treatment with aprepitant suppresses induction of endothelial vascular adhesion molecule (VCAM-1 and E-selectin) and cytokine by ox-LDL. The presence of aprepitant mitigates adhesion of monocytes to endothelial cells and the reduction in eNOS/NO triggered by ox-LDL. Mechanistically, we demonstrate that aprepitant suppresses ERK5-KLF2 axis activation. Silencing of KLF2 abolishes the inhibitory role of aprepitant on ox-LDL-induced inflammatory response, suggesting that its action is dependent on KLF2. Collectively, our data support that aprepitant exerts an anti-inflammatory effect. Further research is required to investigate the therapeutic potential of aprepitant in vascular inflammation resulting from atherosclerosis.

Deformation transfer is an important research problem in geometry processing\ud and computer animation.A fundamental problem for existing deformation transfer\ud methods is to build reliable correspondences. This is challenging, especially\ud when the source and target shapes differ significantly and manual labeling is\ud typically used. We propose a novel deformation transfer method that aims at\ud minimizing user effort. We adapt a biharmonic weight deformation framework\ud which is able to produce plausible deformation even with only a few key points.\ud We then develop an automatic algorithm to identify a minimum set of key points\ud on the source model that characterizes the deformation well. While minimal user\ud effort is still needed to specify corresponding points on the target model for the\ud selected key points, our approach avoids the difficult problem of choosing key\ud points. Experimental results demonstrate that our method, despite requiring\ud little user effort, produces better deformation results than alternative solutions.\ud Keywords: shape deformation; biharmonic weights; key point selection;\ud deformation transfer

Selective catalytic reduction of NO by NH3 over supported vanadium oxide catalysts has been studied for decades, but the studies mostly concentrated on the dominant N2 product with much less attention paid to the formation of the undesired N2O product. In the present study, fundamental aspects of the N2O formation reaction were elucidated by a series of temperature-programmed surface reaction studies with isotopic labelled reactants. The surface vanadium oxide species on the TiO2 support are active sites for the N2O formation reaction, while tungsten species mainly function as promoters. Oxygen from NO, gaseous O2 and catalyst oxygen all function as oxygen sources for formation of N2O (∼50%, ∼30% and ∼20%, respectively). The rate-determining-step for N2O formation involves breaking of the ammonia N H bond. These new molecular level insights have the potential to guide the rational design of improved SCR catalysts for diesel engines with reduced N2O produced.

The nuclear energy plays an important role in world energy production, and the safety of nuclear power plant has drawn increasing attention as well, where the decay heat removal system is an essential part of nuclear plants to ensure its passive safety. This paper aims to propose the way to achieve entirely passive cooling for spent fuel pool. A separate heat pipe assisted passive cooling system with a large cooling capability of 16 MW is discussed, which focuses on passive cooling in the condenser section by mean of natural draft air cooling. After comparing several condenser section configurations, the optimization of the cooling system is discussed to meet the demands of both high-efficiency heat transfer and economic feasibility. In order to find an overall optimal solution for the passive cooling system with the minimum cost, the multi-objective optimization method is employed to investigate a set of system parameters.

Elevated atmospheric CO2 (EC) and temperature (ET) strongly affect agricultural production, but the mechanism through which EC and/or ET influence starch granules and their relationship to cooked rice taste remain largely unknown. Therefore, a field experiment using a popular japonica cultivar grown in a temperature/free-air CO2 enrichment environment was conducted to investigate the responses of volume and fine structure of starch granules and their formation physiology to EC (+200 ppm) and/or ET (+1 °C) in 2015–2016. EC markedly enhanced the activity of soluble-starch synthase and granule-bound starch synthase by 28.0% and 27.9% respectively, thereby increasing the long chains and the volume of starch granules. However, EC decreased the activity of starch-branch enzyme by 7.5% possibly via the pathway of ethylene signalling (EC prominently decreased the ethylene evolution rate of rice grains by 28.8%), resulting in a remarkable decrease in α-1′6 glucosidic bonds and significant increase in the iodine-binding capacity and double helix in starch molecules. These EC-induced changes in morphology and fine structure of starch granules synergistically altered the thermal properties of rice flour and eventually improved the cohesiveness and taste of cooked rice, as suggested by the significant relationships between them. ET partially offset the beneficial EC effects in most cases. However, few remarkable CO2 × temperature or CO2 × year effects were detected, indicating that the effects of EC on starch granules and rice taste less varied with meteorological conditions. These findings have important implications on rice palatability and for the development of adaptive strategies in the starch industry in future environment.

Shape deformation is one of the fundamental techniques in geometric processing. One principle of deformation is to preserve the geometric details while distributing the necessary distortions uniformly. To achieve this, state-of-the-art techniques deform shapes in a locally as-rigid-as-possible (ARAP) manner. Existing ARAP deformation methods optimize rigid transformations in the 1-ring neighborhoods and maintain the consistency between adjacent pairs of rigid transformations by single overlapping edges. In this paper, we make one step further and propose to use larger local neighborhoods to enhance the consistency of adjacent rigid transformations. This is helpful to keep the geometric details better and distribute the distortions more uniformly. Moreover, the size of the expanded local neighborhoods provides an intuitive parameter to adjust physical stiffness. The larger the neighborhood is, the more rigid the material is. Based on these, we propose a novel rigidity controllable mesh deformation method where shape rigidity can be flexibly adjusted. The size of the local neighborhoods can be learned from datasets of deforming objects automatically or specified by the user, and may vary over the surface to simulate shapes composed of mixed materials. Various examples are provided to demonstrate the effectiveness of our method.

Window is a basic building element that can significantly influence the indoor thermal and lighting environment, in evaluating the shading performance of a window system with shading device, the solar heat gain coefficient (SHGC) is of key factor. This paper analyzed the optimal constant solar heat gain coefficient (SHGC) in several typical climate zones in USA and China, the SHGC values were compared according to their latitudes. Based on a grid shading configuration for window, the optimization of grid pitch for energy saving was conducted. The optimal SHGC decreases gradually with the decrease of latitude, the effect of shading device becomes more obvious. The window with optimal SHGC could reduce total building load up to 37.8% in selected USA cities and 24.8% in selected China cities. For the same city and grid pitch, more than 6 times difference emerges from summer to winter. The minimum geometrical shading coefficient (GSC) of grid shading increases with the decrease of latitude.

The rapidly increasing atmospheric CO2 is accompanied by global warming. However, the effects of the elevated CO2 concentration (EC) and/or air temperature (ET) on starch morphology, structure and thermal properties which considerably contribute to the taste of cooked rice have not been reported to date. Therefore, a field experiment using a temperature/free-air CO2 enrichment facility was conducted with EC (+200 ppm) and/or ET (+1 °C) treatments from 2014 to 2016. The surface area of starch granules and proportion of large starch granules were significantly increased by EC and ET, but the most significant increases of 3.4% and 5.9%, respectively, were induced by the combined treatment. EC did not change the crystalline type but altered the order structure of starch molecules: EC averagely decreased the ratios of 1045/1022 and 1022/995 cm−1 by 2.6% and 3.3% respectively, however, significantly increased the crystallinity by 4%. For most cases, EC significantly increased the gelatinization temperature and pasting viscosity of starch, decreased setback, enthalpy and protein content and eventually improved rice taste. Results of correlation analysis suggested that EC affected the thermal properties of starch and the taste of cooked rice mainly by improving the size and molecule order structure of starch granules. Small and few significant ET and EC × ET effects were detected, indicating that the EC influence will be predominant in future climate. These findings will help in improving rice palatability and developing the starch industry.

Although problems are a fundamental dynamics of tourism knowledge production, a systematic, exclusive, and in-depth study of tourism problems or tourism problemology has been overlooked. This study, which represents the first time to examine the nature of tourism problemology, aims to fill this gap. A theoretical model is developed and partially tested through a survey of 212 Chinese tourism researchers. Results show that researchers generally consider problems as difficulties or contradictions that require resolution. Moreover, personal/environmental factors influence the researchers’ understanding of problems, and such understanding further affects their evaluation and selection of problems at the early stage of research. The study highlights the significance of problems as an important, yet overlooked reflexivity of tourism knowledge production.

3D model deformation has been an active research topic in geometric processing. Due to its efficiency, linear blend skinning (LBS) and its follow-up methods are widely used in practical applications as an efficient method for deforming vector images, geometric models and animated characters. LBS needs to determine the control handles and specify their influence weights, which requires expertise and is time-consuming. Further studies have proposed a method for efficiently calculating bounded biharmonic weights of given control handles which reduces user effort and produces smooth deformation results. The algorithm defines a high-order shape-aware smoothness function which tends to produce smooth deformation results, but fails to generate locally rigid deformations.\ud \ud To address this, we propose a novel data-driven approach to producing improved weights for handles that makes full use of available 3D model data by optimizing an energy consisting of data-driven, rigidity and sparsity terms, while maintaining its advantage of allowing handles of various forms. We further devise an efficient iterative optimization scheme. Through contrast experiments, it clearly shows that linear blend skinning based on our optimized weights better reflects the deformation characteristics of the model, leading to more accurate deformation results, outperforming existing methods. The method also retains real-time performance even with a large number of deformation examples. Our ablation experiments also show that each energy term is essential.

Amyloid fibrillogenesis has been involved in at least 40 different degenerative diseases. The 51-residue polypeptide hormone insulin, which is associated with type II diabetes, has been demonstrated to fibrillate in vitro. With bovine insulin as a model, the research presented here examines the influence of two simple, unstructured d,l -lysine-co-glycine ( d,l -lys-co-gly) and d,l -lysine-co-L-phenylalanine ( d,l -lys-co-phe) copolypeptides, on the in vitro fibril formation process of bovine insulin at pH 2.0 and 55 °C. Our results showed that amyloid fibrillogenesis of insulin may be suppressed by both copolypeptides in a concentration-dependent fashion. In addition, the copolypeptides with higher molar fractions of glycine or l -phenylalanine residue, which are considered to possess higher hydrophobic interacting capacities, demonstrated the superior inhibitory potency against insulin fibril formation. Our findings suggest that the association of insulin and copolypeptides, which is likely dominated by hydrophobic interactions and hydrogen bonding, may mitigate the extent of insulin fibrillogenesis. We believe the results from this work may contribute to the understanding of the molecular factors affecting amyloid fibrillation and the molecular mechanism(s) of the interactions between the unstructured polypeptides and amyloid-forming proteins.

Many non-photorealistic rendering techniques exist to produce artistic effects from given images. Inspired by various artists, interesting effects can be produced by using a minimal rendering, where the minimum refers to the number of tones as well as the number and complexity of the primitives used for rendering. Our method is based on various computer vision techniques, and uses a combination of refined lines and blocks (potentially simplified), as well as a small number of tones, to produce abstracted artistic rendering with sufficient elements from the original image. We also considered a variety of methods to produce different artistic styles, such as colour and 2-tone drawings, and use semantic information to improve renderings for faces. By changing some intuitive parameters a wide range of visually pleasing results can be produced. Our method is fully automatic. We demonstrate the effectiveness of our method with extensive experiments and a user study.

Bas-reliefs are a form of flattened artwork, part-way between 3D sculpture and 2D painting. Recent research has considered automatic bas-relief generation from 3D scenes. However, little work has addressed the generation of bas-reliefs from 2D images. In this paper, we propose a method to automatically generate bas-relief surfaces from frontal photographs of human faces, with potential applications to e.g. coinage and commemorative medals.\ud \ud Our method has two steps. Starting from a photograph of a human face, we first generate a plausible image of a bas-relief of the same face. Secondly, we apply shape-from-shading to this generated bas-relief image to determine the 3D shape of the final bas-relief. To model the mapping from an input photograph to the image of a corresponding bas-relief, we use a feedforward network. The training data comprises images generated from an input 3D model of a face, and images generated from a corresponding bas-relief; the latter is produced by an existing 3D model-to-bas-relief algorithm. A saliency map of the face controls both model building, and bas-relief generation.\ud \ud Our experimental results demonstrate that the generated bas-relief surfaces are smooth and plausible, with correct global geometric nature, the latter giving them a stable appearance under changes of viewing direction and illumination.

The rapid expansion of e-commerce at the beginning of 21st century has had a significant impact on intellectual property management. A particular area of concern is the misuse of trademarks and trademark protection. Trademarks are proprietary words and images with high reputational value; they are important assets, often used as a marketing tool, which require infringement protection. One of the issues considered during infringement litigation is the visual, conceptual and phonetic similarity of different trademarks. In particular, the conceptual similarity of trademarks is an area never previously studied in information retrieval. This paper focuses on this important aspect by proposing a conceptual model of the comparison process, aimed at retrieving conceptually similar trademarks. The proposed model employs natural language processing and semantic technology to compute the conceptual similarity between trademarks.

Trademarks are distinctive visual symbols with high reputational value, due to the perception of quality and innovation associated with them. They are important reputational assets used as a marketing tool to convey a certain assurance of quality, innovation, and the standards, which the manufacturer seeks to maintain. This motivates the need for trademark protection by providing a solution to prevent infringement. This problem can be addressed by developing retrieval systems capable of comparing the visual similarity of trademarks. This paper contributes to the research in this field by proposing an innovative trademark retrieval technique with improved retrieval performance due to the integration of global and local descriptors. The global descriptor employed is the Zernike moment's coefficients. The local descriptor is the edge-gradient co-occurrence matrix, derived from the contour information that is considered very important in human perception of visual similarity. The proposed retrieval technique is tested using the standard MPEG-7 shape database of 1400 images and the MPEG-7 trademark database of 3260 images. The results show 5% precision/recall improvement in the case of the MPEG-7 shape database, as well as 2.35% Bull's eye score improvement and 19.8% NMRR score improvement for the 10 randomly selected trademarks from the MPEG-7 trademarks database.

This study aims to test whether core-periphery structure (C/PS), a widely practiced and important form of structure, exists in tourist destination image (TDI). Past tourism research has identified three-dimensional and causal-networking structures of TDI, but generally fails to recognize C/PS as an alternative. This study develops a conceptual model of C/PS of TDI via a synthesis of existing works on structure, structuralism, and C/PS. Testing the model, quantitatively and qualitatively in the context of Beijing city, demonstrates that TDI can be core-peripherally structured. This alternative TDI structure expands existing perspectives in understanding the structures of TDI, offers useful tools for destination image management, and highlights the complex, pluralistic and constructed nature of mental struc- tures. Keywords: destination image, core-periphery, structure, structuralism, constructivism, Beijing. 2012 Elsevier Ltd. All rights reserved.

Compared to 2D textures, solid textures can represent not only the bounding surfaces, but also their interiors. Existing solid texture synthesis methods pay little attention to the generation of conforming textures that capture geometric structures or reflect the artists’ design intentions. In this paper, we propose a novel approach to synthesizing solid textures using 2D exemplars. The generated textures locally agree with a tensor field derived from user sketching curves. We use a deterministic approach and only a small portion of the voxels needs to be synthesized on demand. Correction is fundamental in deterministic texture synthesis. We propose a history windows representation, which is general enough to unifiedly represent various previous correction schemes, and a dual grid scheme based on it to significantly reduce the dependent voxels while still producing high quality results. Experiments demonstrate that our method produces significantly improved solid textures with a small amount of user interaction.

In this paper we present a new algorithm which turns an unstructured triangle mesh into a quad dominant mesh with edges well aligned to the principal directions of the underlying surface. Instead of computing a globally smooth parameterization or integrating curvature lines along a tangent vector field, we simply apply an iterative relaxation scheme which incrementally aligns the mesh edges to the principal directions. We further obtain the quad dominant mesh by dropping the not-aligned diagonal edges from the triangle mesh. A post-processing stage is introduced to further improve the results. The major advantage of our algorithm is its conceptual simplicity since it is merely based on elementary mesh operations such as edge collapse, flip, and split. Various results are presented in the paper; they show a good alignment to surface features and rather uniform distribution of mesh vertices. This makes them well suited, e.g., as Catmull-Clark Subdivision control meshes.

Phase change materials can exist in two different phases, the amorphous and the crystalline phase, which exhibit distinctly different physical properties. It is possible to repeatedly switch the state of these materials, from the amorphous phase to the crystalline phase by heating the material above its crystallization temperature, and from the crystalline to the amorphous phase by melt-quenching. Phase change materials have been utilized very successfully in all modern optical re-writable storage media such as CDs, DVDs and Blu-ray disks. Recently, they have also been applied to solid-state memory devices where their large difference in electrical resistivity is used to store information. This paper reviews the unique properties of phase change materials in particular as they are important for their application to these devices.

A novel channel-program and erase method is presented to replace the FN tunneling operation for SONOS cells in NAND architecture for the first time [Hsu TH, Wu JY, King YC, Lue HT, Shih YH, Lai EK, et al. A novel channel-program–erase technique with substrate transient hot carrier injection for SONOS memory application. In: Tech digest 2006 European solid-state device research conference (ESSDERC); 2006. p. 222–5], [1] . The proposed operation utilizes substrate transient hot electron (STHE) injection and substrate transient hot-hole (STHH) injection for programming and erasing, respectively. Gate bias polarity serves to control whether hot electrons or hot holes are injected into the nitride storage layer. More efficient program and erase operations are achieved compared to the conventional Fowler–Nordheim (FN) tunneling method. The new technique operates at lower programming voltages and with shorter duration pulses, thus increases the programming throughput. Moreover, good program/erase disturb immunity, cycling endurance and data retention are demonstrated.

The extraction of curvature information for surfaces is a basic problem of Geometry Processing. Recently an integral invariant solution of this problem was presented, which is based on principal component analysis of local neighborhoods defined by kernel balls of various sizes. It is not only robust to noise, but also adjusts to the level of detail required. In the present paper we show an asymptotic analysis of the moments of inertia and the principal directions which are used in this approach. We also address implementation and, briefly, robustness issues and applications.

Most approaches to least squares fitting of a B-spline surface to measurement data require a parametrization of the data point set and the choice of suitable knot vectors. We propose to use uniform knots in connection with a feature sensitive parametrization. This parametrization allocates more parameter space to highly curved feature regions and thus automatically provides more control points where they are needed.

The charge trapping behavior of SiON thin films using various processing methods are studied. The transient analysis method [Lue HT, Shih YH, Hsieh KY, Liu R, Lu CY. A transient analysis method to characterize the trap vertical location in nitride-trapping devices. IEEE Electron Dev Lett 2004;25:816–8] reveals that SiON has a higher capture efficiency than SiN so that gate injected electrons are mostly stopped at the interface between top oxide and trapping layer, independent of whether the SiON is formed by thermal oxidation of SiN or direct LPCVD deposition. On the other hand, the excess Si piling-up behavior is observed during oxidation process over SiN, and it shows correlation with the native negative charge. Therefore, the effect of excess Si piling-up and SiON trapping layer are discriminated for the first time.