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81.
82.
It is difficult to render caustic patterns at interactive frame rates. This paper introduces new rendering techniques that relax current constraints, allowing scenes with moving, non-rigid scene objects, rigid caustic objects, and rotating directional light sources to be rendered in real-time with GPU hardware acceleration. Because our algorithm estimates the intensity and the direction of caustic light, rendering of non-Lambertian surfaces is supported. Previous caustics algorithms have separated the problem into pre-rendering and rendering phases, storing intermediate results in data structures such as photon maps or radiance transfer functions. Our central idea is to use specially parameterized spot lights, called caustic spot lights (CSLs), as the intermediate representation of a two-phase algorithm. CSLs are flexible enough that a small number can approximate the light leaving a caustic object, yet simple enough that they can be efficiently evaluated by a pixel shader program during accelerated rendering.We extend our approach to support changing lighting direction by further dividing the pre-rendering phase into per-scene and per-frame components: the per-frame phase computes frame-specific CSLs by interpolating between CSLs that were pre-computed with differing light directions. 相似文献
83.
84.
85.
包军卫 《单片机与嵌入式系统应用》2009,(3):51-52,55
描述一个基于单片机的智能型电子清纱器的系统结构和实现方案。系统采用RS-485总线技术,利用单片机改造传统的模拟电子清纱器,采用软硬件结合的抗干扰措施,实现了实时数据采集,数据存储、数据打印等高级功能。文中阐述了系统各组成部分的功能和实现方案,重点介绍了主、从机之间的通信规约以及通信软件模块的编程思路。 相似文献
86.
电子纸显示控制器S1D13521的人机交互设计 总被引:2,自引:0,他引:2
新型电子纸显示控制器SID13521的推出,为提升电子纸显示屏人机界面体验带来了强大技术支持。结合SID13521诸多新特性,本文建立一种控制一反馈人机交互结构模型,在此基础上设计了电子纸人机交互基本操控手势及界面布局,并通过动态视觉反馈设计提升交互体验。经在津科V30型手持阅读器上验证,该设计简便易行、效果良好。 相似文献
87.
This paper is concerned with the problem of boosting social annotations using propagation, which is also called social propagation. In particular, we focus on propagating social annotations of web pages (e.g., annotations in Del.icio.us). Social annotations
are novel resources and valuable in many web applications, including web search and browsing. Although they are developing
fast, social annotations of web pages cover only a small proportion (<0.1%) of the World Wide Web. To alleviate the low coverage
of annotations, a general propagation model based on Random Surfer is proposed. Specifically, four steps are included, namely
basic propagation, multiple-annotation propagation, multiple-link-type propagation, and constraint-guided propagation. The
model is evaluated on a dataset of 40,422 web pages randomly sampled from 100 most popular English sites and ten famous academic
sites. Each page’s annotations are obtained by querying the history interface of Del.icio.us. Experimental results show that
the proposed model is very effective in increasing the coverage of annotations while still preserving novel properties of
social annotations. Applications of propagated annotations on web search and classification further verify the effectiveness
of the model. 相似文献
88.
GUI软件测试文档辅助工具的设计与实现 总被引:1,自引:0,他引:1
GUI软件的应用越来越广泛的同时,GUI软件的测试任务变得也越来越重,如何减少GUI软件测试文档的编写负担成为一个值得关注的问题。文中介绍了一款自主研发的测试文档辅助工具AutoDoc的设计和实现,AutoDoc通过调用Windows底层的Hook消息处理函数,来监视用户操作及系统响应的各种消息,达到录制的目的。文中着重说明了工具实现过程中的解决方案,结合例子对工具进行实验,实验证明本工具可以有效地提高测试文档编写的效率。 相似文献
89.
Qin Yang Bingqing Ge Pei Yuan Shuting Luo Hongwei Zhang Zhengyu Zhao Jiujun Zhang Shidong Wang Xiaojun Bao Xiangdong Yao 《Advanced functional materials》2023,33(25):2214588
Electrocatalytic hydrogenation (ECH) is a burgeoning strategy for the sustainable utilization of hydrogen. However, how to effectively suppress the competitive hydrogen evolution reaction (HER) is a big challenge to ECH catalysis. In this study, amine (NH2 R)-coordinated Pd nanoparticles loaded on carbon felt (Pd@CF) as a catalyst is successfully synthesized by a one-step solvothermal reduction method using oleylamine as the reducing agent. An exceptional ECH reactivity on benzaldehyde is achieved on the optimal Pd@CF catalyst in terms of a high conversion (89.7%) and selectivity toward benzyl alcohol (89.8%) at −0.4 V in 60 min. Notably, the Faradaic efficiency for producing benzyl alcohol is up to 90.2%, much higher than that catalyzed by Pd@CF-without N-group (41.1%) and thecommercial Pd/C (20.9%). The excellent ECH performance of Pd@CF can be attributed to the enriched electrons on Pd surface resulted from the introduction of NH2 R groups, which strengthens both the adsorption of benzaldehyde and the adsorbed hydrogen (Hads) on Pd, preventing the combination of Hads to form H2, that is, inhibiting the HER. This study gives a new insight into design principles of highly efficient electrocatalysts for the hydrogenation of unsaturated aldehydes molecules. 相似文献
90.
Chenjie Song Yuhan Zhang Jinying Bao Zizheng Wang Lanying Zhang Jian Sun Ruochen Lan Zhan Yu Siquan Zhu Huai Yang 《Advanced functional materials》2023,33(17):2213771
Liquid crystalline polymers (LCPs), especially liquid crystalline elastomers (LCEs) can generate ultrahigh shape change amplitude but has lower mechanical strength. Although some attempts have been tried to improve the mechanical performance of LCE, there are still limitations including complicated fabrication and high actuation temperature. Here, a versatile method is reported to fabricate light-driven actuator by covalently cross-linking polyurethane (PU) into LCP networks (PULCN). This new scheme is distinct from the previous interpenetrating network strategy, the hydrogen bonds and covalent bonds are used in this study to improve the miscibility of non-liquid-crystalline PU and LCP materials and enhance the stability of the composite system. This material not only possesses the shape memory properties of PU but shows shape-changing behavior of LCPs. With a shrinkage ratio of 20% at the phase transition temperature, the prepared materials reached a maximum mechanical strength of 20 MPa, higher than conventional LCP. Meanwhile, the resulting film shows diverse and programmable initial shapes by constructing crosslinking density gradient across the thickness of the film. By integration of PULCN with near-infrared light-responsive polydopamine, local and sequential light control is achieved. This study may provide a new route for the fabrication of programmable and mechanically robust light-driven soft actuator. 相似文献