基于局部线性变换的色阶映射算法

为了提高高动态图像显示的视觉效果,提出了一种基于局部线性变换的色阶映射算法;针对图像直接线性压缩能力较差的缺点,本文提出一种局部的线性变换模型;由于局部窗的结构,是利用局部窗的中心像素点与窗内的其他像素点的均值,方差的关系构造而成,因此基于局部线性变换的色阶映射算法能够抑制由具有高对比度的图像边缘所引起的鬼影和光晕现象;首先,根据线性变换将图像的色阶映射转换为求解泛函的最优解;其次,通过推导求解出线性变换的参数并将泛函最优化问题转换为求解一个线性方程组问题;最后求解线性方程组,得出视觉效果较好的低动态范围图像;有效避免传统色阶映射出现的光晕和亮度不连续的现象,能够更多的保留高动态图像的细节;最后通过实验结果对比分析,通过信息熵和对比度两个参数可以体现文中算法较好。     

高动态图像色调映射技术新进展*

传统显示设备受自身动态范围限制,无法很好地显示高动态图像的效果,需要用色调映射方法进行合理的动态域压缩,获得更好的图像显示质量。综述了现有高动态图像的色调映射技术,首先简要介绍了高动态图像色调映射方法的概念;再介绍了色调映射算子的分类,以色调映射处理方式为主分别介绍了空域不变算法、空域变化算法及混合算法这三大类算子近年来发展起来的各种新方法,并指出各种方法的技术优势及对此进行了归纳总结;最后阐述了该技术的应用领域及其继续发展的方向。     

一种动态CTCSS系统的设计与实现

该文提出了动态CTCSS控制模块,利用亚音频作为识别信号来实现转信台的有条件中转。模块中的单片机可以自动识别解码后的亚音频信号,并根据编程产生与接收亚音频相呼应的、指定的亚音频信号,既达到去除人为的同频干扰,又保障正常的通信需求。通过适当的亚音频分组,可以保证数个单位或部门的通信需求,相互之间不交叉,可有效地提高了频率的利用率。同时,利用该系统中的同播系统,可对各部门集中调度,提高了指挥的效率,该模块可广泛地应用于调度、抢险和报警等系统。     

《老人与海》——集悲喜于一身的完美混合体

海明威在<老人与海>的创作中独具匠心地为小说中的主要角色--圣地亚哥和大马林鱼赋予了悲喜兼备的特点,同时还折射出海明威自身所同时具备的悲和喜两个既相互对立又相互依存的方面.本文对小说中这两个主要角色以及小说作者从悲喜冈素两方面进行详细分析,帮助广大读者从一个全新的角度欣赏这部世界名著.     

基于时域自适应滤波及非局部平均的夜视图像去噪算法

为了增强夜视图像的可视性和清晰度,提出了一种适用于夜视环境的视频图像去噪和增强算法。首先在噪声消除方面,提出了一种基于卡尔曼结构更新的运动自适应时域滤波器。然后利用带有自适应限幅阈值的伽马校正调整RGB直方图,来增加去噪视频图像的动态范围。最后,使用非局部平均(NLM)去噪滤波器消除剩余噪声。提出的方法能够直接用于颜色滤波阵列(CFA)原始视频图像,以便获得较低的内存消耗。在夜间环境(低于0.1 lux)下,利用2百万像素CMOS传感器进行了具体测试,实验结果表明,相比现有的夜视图像增强方法,提出的视频图像增强法在夜间环境下均表现出了更加良好的性能指标。     

Synthesis of succinylated poly(4‐hydroxystyrene) and its application for negative‐tone photoresist

Atom transfer radical polymerization (ATRP) was used to prepare poly(acetoxystyrene) (PAS) with a controlled molecular weight and narrow polydispersity. Using 1‐phenylethylbromide (PEBr)/CuBr/Cu(0)/2,2′‐bipyridine as an initiating system, the heterogeneous ATRP of 4‐acetoxystyrene was carried out to form PAS as a precursor polymer. The reaction follows the first‐order kinetics with respect to the conversion of monomer. A linear molecular weight (polydispersities Mw/Mn = 1.07–1.27) indicates the “living”/controlled nature of polymerization. The obtained PAS was chemically modified to obtain succinylated poly(hydroxystyrene) (Succ‐PHS). The formulation of Succ‐PHS, crosslinker (benzoguanamine‐formaldehyde), and triphenylsulfonium triflate (TPST) as a photo acid generator (PAG) was carried out by UV irradiation using an i‐line tool. The performance of the resultant polymer as the negative resist pattern photoresist for photolithography was studied with instrumental techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3560–3566, 2007     

Lexical Tones and Word Learning in Mandarin-Speaking Children at Three Years of Age

Unlike Indo-European languages, Mandarin relies heavily on lexical tones to distinguish word identity. Using the intermodal preferential looking paradigm, this study examined 3-year-old Mandarin-speakers' ability to use Mandarin lexical tones in learning new words. Results showed that when children were presented with Tone 2 (rising) and Tone 4 (falling) pairs, children successfully learned both words. However, when children were presented with Tone 2 and Tone 3 (dipping) pairs, they learned the Tone 2 word but not the Tone 3 one. Children were then divided into two groups based on their learning performance on the Tone 3 word. Successful learning of Tone 3 words was observed in the high performers but not in the low performers, who consistently misused Tone 3 as Tone 2. This study showed that Mandarin-speaking 3-year-olds could use lexical tones to learn words under experimental conditions, and that the difficulty of Tone 3 acquisition may be related to its lower level of perceptual distinctiveness compared with other tones.     

音调/音量控制器芯片M61500FP及应用

介绍了内置QSurround系统的音响控制器IC、M61500FP的组成框图、引脚功能、控制信号与数据格式、功能特点及应用。     

轻型印刷纸的生产工艺与技术

文章通过对轻型印刷纸的产品特性、生产实践中的工艺技术条件作了介绍,并对生产中所遇到的产品质量和工艺技术问题进行若干讨论,使该产品在生产中得到不断的完善。     

Tinnitus and Hearing Loss in Hamsters (Mesocricetus auratus) Exposed to Loud Sound.

Hamsters were trained to go left and right to sounds on their left and right sides, respectively. Silent trials were occasionally given in which no sound was presented. Hamsters exposed to a loud 2- or 10-kHz tone in 1 ear often shifted their responding on the silent trials to the side of the exposed ear, suggesting that they perceived a sound in that ear (i.e., tinnitus). The degree of tinnitus was related to the degree of the accompanying hearing loss (estimated by the auditory brainstem response). However, a conductive hearing loss (plugging 1 ear) did not cause a hamster to test positive for tinnitus. Tinnitus could be demonstrated within minutes following tone exposure, indicating an immediate onset, as occurs in humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)