Digital fonts are easily available today and their use has become widespread. Nevertheless, the visual quality of printed and displayed text and the technical quality of digital typefaces are often unsatisfactory. The foremost reason for this situation is that font manufacturing systems manipulate font representations through low-level operations. In this paper we examine several aspects of font quality, and present a method for enhancing the quality of a typeface given in today's standard representation, the outline (boundary) representation. The method is based on the usage of high-level typographic features, and includes enhancements to both individual glyphs and complete fonts. Glyph enhancements include elimination of redundant points, insertion of essential points, corrections to contour orientations and inter-penetrations, and vertical and horizontal coherence. Font enhancements include regularization of font weights and sizes, serif unification, and feature extraction and discrimination. Our method is comprised of several algorithms that have been implemented in a commercial font manufacturing system, achieving enhanced quality of the fonts produced. 相似文献
Virtual Reality - Virtual reality (VR) sickness is a condition that may occur during or after exposure to a virtual environment and can induce symptoms such as headache and eye strain. VR sickness... 相似文献
In the state-of-the-art parallel programming approaches OpenCL and CUDA, so-called host code is required for program’s execution. Efficiently implementing host code is often a cumbersome task, especially when executing OpenCL and CUDA programs on systems with multiple nodes, each comprising different devices, e.g., multi-core CPU and graphics processing units; the programmer is responsible for explicitly managing node’s and device’s memory, synchronizing computations with data transfers between devices of potentially different nodes and for optimizing data transfers between devices’ memories and nodes’ main memories, e.g., by using pinned main memory for accelerating data transfers and overlapping the transfers with computations. We develop distributed OpenCL/CUDA abstraction layer (dOCAL)—a novel high-level C++ library that simplifies the development of host code. dOCAL combines major advantages over the state-of-the-art high-level approaches: (1) it simplifies implementing both OpenCL and CUDA host code by providing a simple-to-use, high-level abstraction API; (2) it supports executing arbitrary OpenCL and CUDA programs; (3) it allows conveniently targeting the devices of different nodes by automatically managing node-to-node communications; (4) it simplifies implementing data transfer optimizations by providing different, specially allocated memory regions, e.g., pinned main memory for overlapping data transfers with computations; (5) it optimizes memory management by automatically avoiding unnecessary data transfers; (6) it enables interoperability between OpenCL and CUDA host code for systems with devices from different vendors. Our experiments show that dOCAL significantly simplifies the development of host code for heterogeneous and distributed systems, with a low runtime overhead.
Water-soluble silicon nanoparticles (SiNPs) have been synthesized with photoluminescence quantum yield more than 32% via a hydrothermal treatment of 3-aminopropyltriethoxysilane as silicon sources and maleic acid (MA) as surface-stabilizing ligands. Prepared SiNPs showed the presence of carboxylic acid groups through the incorporation of MA. The presence of 48.8 and 51.2% of Si–Si and Si–O binding was observed in the resulting carboxylic acid-functionalized SiNPs (COOH-SiNPs). As revealed by the fluorescence lifetime images, COOH-SiNPs possesses several fluorophores mainly composed of above Si–Si binding inside of single particle, which explains the excitation-dependent fluorescence emission behavior of COOH-SiNPs. Also, the presence of oxides mainly composed of Si–O binding and MA on the surface of COOH-SiNPs provides long-term stability for both fluorescence and dispersion. The potential use of COOH-SiNPs as fluorescence bioimaging agents for cellular media has been demonstrated. COOH-SiNPs showed excellent cell viability more than 91% for both MDAMB and MDCK cells even in 1,000 ppm concentration, and multicolor fluorescence imaging (blue, green, and red) of MDAMB cells was successfully accomplished with different excitation wavelengths. 相似文献
Machine Learning - The COVID-19 global pandemic is a threat not only to the health of millions of individuals, but also to the stability of infrastructure and economies around the world. The... 相似文献
Equations suitable for computing specific interfacial energies of precipitates dissolving by a first order transformation were developed on the basis of the singularities taking place at the critical temperature,Tc, under equilibrium conditions. These equations employ data which can be determined by differential scanning calorimetry. Also the conditions for reaching dynamic equilibrium of particle volume fraction belowTc are analysed in terms of a maximum permissible experimental heating rate. The results obtained for disperse order inCu-Al alloys are in good agreement with those expected from the observed particle features. 相似文献
Benzenoids are compounds associated with floral and fruity flavours in flowers, fruits and leaves and present a role in hormonal signalling in plants. These molecules are produced by the phenyl ammonia lyase pathway. However, some yeasts can also synthesize them from aromatic amino acids using an alternative pathway that remains unknown. Hanseniaspora vineae can produce benzenoids at levels up to two orders of magnitude higher than Saccharomyces species, so it is a model microorganism for studying benzenoid biosynthesis pathways in yeast. According to their genomes, several enzymes have been proposed to be involved in a mandelate pathway similar to that described for some prokaryotic cells. Among them, the ARO10 gene product could present benzoylformate decarboxylase activity. This enzyme catalyses the decarboxylation of benzoylformate into benzaldehyde at the end of the mandelate pathway in benzyl alcohol formation. Two homologous genes of ARO10 were found in the two sequenced H.vineae strains. In this study, nine other H.vineae strains were analysed to detect the presence and per cent homology of ARO10 sequences by PCR using specific primers designed for this species. Also, the copy number of the genes was estimated by quantitative PCR. To verify the relation of ARO10 with the production of benzyl alcohol during fermentation, a deletion mutant in the ARO10 gene of Saccharomyces cerevisiae was used. The two HvARO10 paralogues were analysed and compared with other α-ketoacid decarboxylases at the sequence and structural level. 相似文献
There is active debate regarding whether diagnosable depression exists on a continuum with subthreshold depressive symptoms or represents a categorically distinct phenomenon. To address this question, multiple indexes of dysfunction (psychosocial difficulties, mental health treatment history, and future incidence of major depression and substance abuse/dependence) were examined as a function of the extent of depressive symptoms in 3 large community samples (adolescent, adult, and older adult; N?=?3,003). Increasing levels of depressive symptoms were associated with increasing levels of psychosocial dysfunction and incidence of major depression and substance use disorders. These findings suggest that (a) the clinical significance of depressive symptoms does not depend on crossing the major depressive diagnostic threshold and (b) depression may best be conceptualized as a continuum. Limitations of the present study are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
This study examines the trends of public opinions concerning the introduction of hydrogen vehicles in Greater Stavanger as well as public attitudes towards the natural environment over the course of the three-year period. This study is based on two surveys of the hydrogen highway project (HyNor) which were collected in the Greater Stavanger region, the west coast of Norway, between 2006 and 2009 (n=2000). The results of the study highlight that – despite an increased awareness of hydrogen vehicles – the proportions of those with pro-environment attitudes who support hydrogen vehicles’ introduction decreased between 2006 and 2009. The results reveal that knowledge about sustainable environment can affect hydrogen energy's acceptance whereas the level of pro-environment attitudes can increase not only public acceptance of hydrogen vehicles, but also people's willingness to pay for hydrogen fuels. These results were consistently found throughout the observed periods, based on the Greater Stavanger's case. A set of recommendations was discussed to improve public acceptance of hydrogen vehicles, and the next avenue of research regarding analysis of public acceptance and awareness about hydrogen vehicles was proposed. 相似文献