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1.
Fast image codecs are a current need in applications that deal with large amounts of images. Graphics Processing Units (GPUs) are suitable processors to speed up most kinds of algorithms, especially when they allow fine-grain parallelism. Bitplane Coding with Parallel Coefficient processing (BPC-PaCo) is a recently proposed algorithm for the core stage of wavelet-based image codecs tailored for the highly parallel architectures of GPUs. This algorithm provides complexity scalability to allow faster execution at the expense of coding efficiency. Its main drawback is that the speedup and loss in image quality is controlled only roughly, resulting in visible distortion at low and medium rates. This paper addresses this issue by integrating techniques of visually lossless coding into BPC-PaCo. The resulting method minimizes the visual distortion introduced in the compressed file, obtaining higher-quality images to a human observer. Experimental results also indicate 12% speedups with respect to BPC-PaCo.  相似文献   
2.
In the last few decades, global warming, environmental pollution, and an energy shortage of fossil fuel may cause a severe economic crisis and health threats. Storage, conversion, and application of regenerable and dispersive energy would be a promising solution to release this crisis. The development of porous carbon materials from regenerated biomass are competent methods to store energy with high performance and limited environmental damages. In this regard, bio-carbon with abundant surface functional groups and an easily tunable three-dimensional porous structure may be a potential candidate as a sustainable and green carbon material. Up to now, although some literature has screened the biomass source, reaction temperature, and activator dosage during thermochemical synthesis, a comprehensive evaluation and a detailed discussion of the relationship between raw materials, preparation methods, and the structural and chemical properties of carbon materials are still lacking. Hence, in this review, we first assess the recent advancements in carbonization and activation process of biomass with different compositions and the activity performance in various energy storage applications including supercapacitors, lithium-ion batteries, and hydrogen storage, highlighting the mechanisms and open questions in current energy society. After that, the connections between preparation methods and porous carbon properties including specific surface area, pore volume, and surface chemistry are reviewed in detail. Importantly, we discuss the relationship between the pore structure of prepared porous carbon with surface functional groups, and the energy storage performance in various energy storage fields for different biomass sources and thermal conversion methods. Finally, the conclusion and prospective are concluded to give an outlook for the development of biomass carbon materials, and energy storage applications technologies. This review demonstrates significant potentials for energy applications of biomass materials, and it is expected to inspire new discoveries to promote practical applications of biomass materials in more energy storage and conversion fields.  相似文献   
3.
现有的图像修复方法在处理大面积缺失或高度纹理化的图像时,通常会产生扭曲的结构或与周围区域不一致的模糊纹理,无法重建合理的图像结构。为此,提出了一种基于推理注意力机制的二阶段网络图像修复方法。首先通过边缘生成网络生成合理的幻觉边缘信息,然后在图像补全网络完成图像的重建工作。为了进一步生成视觉效果更逼真的图像,提高图像修复的精确度,在图像补全网络采用推理注意力机制,有效控制了生成特征的不一致性,从而生成更有效的信息。所提方法在多个数据集上进行了实验验证,结果表明该图像修复方法的结构相似性指数达到了88.9%,峰值信噪比达到了25.56 dB,与现有的图像修复方法相比,该方法具有更高的图像修复精确度,生成的图像更逼真。  相似文献   
4.
在传统的轮胎表面缺陷依靠人工检测,存在劳动强度高、受人的主观影响大以及效率低下的问题。针对这一现象,研究了一种基于机器视觉的轮胎表面缺陷3D检测系统。该系统依靠机器视觉系统获取检测轮胎的表面图像,然后创建3D模型、判定缺陷类型,最终实现实时自动预警,为轮胎生产商提供一种自动化检测方案。系统集成了先进的技术、软件和工具,配套的信息管控系统可以对轮胎型号和生产数据进行采集、存储、分析,以便在生产过程中实现更高效、更可靠的质量控制,具有较高的实际应用推广价值。  相似文献   
5.
向森 《电子测试》2021,(6):125-126
电路板在我们的日常生活中非常常见,这就使得印刷电路板的缺陷检测显得尤为重要。AOI作为新兴的检测PCB板缺陷的系统,在生产实际中正在被大家熟知并且应用。相较于传统的检测方式,AOI系统比较灵活,无论是在检测时间还是系统运算上,或者是对相关技术人员的要求相较于传统方式都比较有优势,本文就AOI系统在实际中的应用展开讨论,分析并且介绍了在实际应用中的具体细则。  相似文献   
6.
Multi-channel and single-channel image denoising are on two important development fronts. Integrating multi-channel and single-channel image denoisers for further improvement is a valuable research direction. A natural assumption is that using more useful information is helpful to the output results. In this paper, a novel multi-channel and single-channel fusion paradigm (MSF) is proposed. The proposed MSF works by fusing the estimates of a multi-channel image denoiser and a single-channel image denoiser. The performance of recent multi-channel image denoising methods involved in the proposed MSF can be further improved at low additional time-consuming cost. Specifically, the validity principle of the proposed MSF is that the fused single-channel image denoiser can produce auxiliary estimate for the involved multi-channel image denoiser in a designed underdetermined transform domain. Based on the underdetermined transformation, we create a corresponding orthogonal transformation for fusion and better restore the multi-channel images. The quantitative and visual comparison results demonstrate that the proposed MSF can be effectively applied to several state-of-the-art multi-channel image denoising methods.  相似文献   
7.
Biomass gasification technology under microwave irradiation is a new and novel method, and the energy conversion performances during the process play a guiding role in improving the energy conversion efficiencies and developing the gasification simulation models. In order to improve the energy utilization efficiency of microwave biomass gasification system, this study investigated and presented the energy conversion performances during biomass gasification process under microwave irradiation, and these were materialized through detailing (a) the energy conversion performance in the microwave heating stage, and (b) the energy conversion performance in the microwave assisted biomass gasification stage. Different forms of energies in the biomass microwave gasification process were calculated by the method given in this study based on the experimental data. The results showed that the useful energy (energy in silicon carbide (SiC), 18.73 kJ) accounted for 31.22% of the total energy input (electrical energy, 60.00 kJ) in the heating stage, and the useful energy (energy in the products, 758.55 kJ) accounted for 63.41% of the total energy input (electrical and biomass energy, 1196.28 kJ) in the gasification stage. During the whole biomass gasification process under microwave irradiation, the useful energy output (energy in the products, 758.55 kJ) accounted for 60.38% of the total energy input (electrical and biomass energy, 1256.28 kJ), and the energy in the gas (523.40 kJ) product played a dominate role in product energy (758.55 kJ). The energy loss mainly included the heat loss in the gas flow (89.20 kJ), magnetron loss (191.80 kJ) and microwave dissipation loss (198.00 kJ), which accounted for 7.10%, 15.27% and 15.76% of the total energy, respectively. The contents detailed in this study not only presented the energy conversion performances during microwave assisted gasification process but also supplied important data for developing gasification simulation models.  相似文献   
8.
潘杰  李焰 《化工进展》2020,39(11):4503-4515
化学转化膜是金属表面主要的处理方法之一,具备良好的附着力和耐蚀性,能为铝合金提供一定的临时防护。传统的六价铬酸盐化学转化膜在日渐严苛的环保压力下已经逐渐淘汰,取而代之的是近几年发展迅猛的三价铬及无铬锆基化学转化膜。铝合金可分为铸造铝合金和变形铝合金,按照所含主要合金元素和热处理状态可分为若干个系列和型号。本文选取几种典型的变形铝合金,综述了不同铝合金微观组织对转化膜成膜过程的影响,化学转化液添加剂、预处理和后处理工艺对转化膜性能的调控及作用机理,以及几种典型商业钝化剂在变形铝合金表面的应用。总结了目前变形铝合金表面锆基化学转化膜仍面临的问题和发展趋势,未来化学转化膜需在满足新型铝合金发展要求的基础上,通过不同有机、无机添加剂以及外场作用对转化膜的成膜均一性、完整性进行调控,以提高转化膜的综合性能。  相似文献   
9.
溶液浓差能驱动的逆电渗析反应器制氢实验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
低品位热能制氢技术首先是将热能转换为溶液浓差能,然后通过逆电渗析(RED)反应器将溶液浓差能转换成氢能。为了验证RED反应器能将溶液浓差能转换为氢能,探索关键运行参数变化对能量转换过程的影响。设计了一个由40个膜对所构成的RED反应器,以NaCl水溶液为工作溶液,NaOH水溶液为电极液的制氢系统。通过改变浓/稀溶液入口浓度,溶液过膜流速以及输出电流来考察对RED反应器产氢率、制氢效率和能量转换效率的影响。实验结果发现,浓/稀溶液入口浓度,过膜流速变化均会影响RED反应器的输出电流。在外电路短接条件下,输出电流越大,反应器产氢率和制氢效率越高,但能量转换效率越低。  相似文献   
10.
模拟量模块采用RS485通讯网路,将分散的现场数据点的模拟量经AD变换传输到主机或由PC控制远程主站点。模拟量模块具有计量数据采集、测量数据采集、设备开关状态采集和对外逻辑控制等多项功能,主要用作各种测控终端的数据采集、控制和显示设备,适用于各行业的自动化、信息化系统。本文介绍了一种模拟量模块的应用。  相似文献   
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