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91.
The body color in animals results from billions of years of their natural evolution in order to evade natural enemies, catch
quarries or display themselves beauty, investigation on mechanisms of structural light is an important aspect of bionics.
Based on the phenomenon of Papilio maackii ménétriès’ blue scales changing into green ones immediately after dropping some alcohol aqua on the underwing surface and
soon returning back to the original color, the relationship between microstructure, optics characteristic of scales and changing
color effect were studied using the Olympus Stereomicroscope, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy
(TEM) and Ultraviolet (UV)-Visible Spectrophotometer. The color variation mechanisms of blue scales of Papilio maackii ménétriès in Chinese Northeast were revealed in this paper. When visible lights traveled through the concaver structure with
multilayer reflector and the filled medium with different refractive indices, the reflected lights in definite wavelengths
produced interference and color at that wavelength came into being. It has important academic reference value to biomimetics
design of video stealth materials.
Recommended by Prof. SONG YuQuan, Member of Editorial Committee of Science in China, Series E: Technological Sciences
Supported by the National Natural Science Foundation of China (Grant Nos. 50635030, 30570235), the Key Project of Chinese
Ministry of Education (Grant No. 105059), and Fok Ying Tong Education Foundation (Grant No. 101020) 相似文献
92.
Duan-Shin Lee Benjamin Melamed Amy R. Reibman Bhaskar Sengupta 《Performance Evaluation》1992,16(1-3):21-34
The transport of video images is likely to be a major application of high-speed networks of the future. These applications are capable of utilizing the high bandwidths that will become available with the advent of B-ISDN. In this paper, we propose a new methodology (called TES) for modeling the frame bitrate stream generated by compressed video sources. The main characteristic of this method is that it can model an arbitrary marginal distribution and approximate the autocorrelation structure of the random bitrate process generated by compressed frames. We present a modeling example utilizing this method, based on data from a video coding algorithm employing a layering technique. Using the source model, we develop a simulation model of a multiplexer of video sources. We show that this model can be used to address a number of design issues that arise in this class of problem. In particular, we show that for a layered video coding algorithm, it is possible to have a gain in the number of sources multiplexed at the cost of some loss of low priority packets. 相似文献
93.
饮料包装的计算机控制和管理 总被引:1,自引:1,他引:0
着重介绍计算机技术在饮料包装方面应用的发展情况,灌装生产流水线的计算机控制和管理,自动装卸搬运系统和计算机仓库管理系统等。 相似文献
94.
Masahiro Baba Goh Itoh Haruhiko Okumura 《Journal of the Society for Information Display》2007,15(3):205-211
Abstract— In this paper, a software‐processed edge‐ and level‐adaptive overdrive (SELAO) method, which is a novel overdrive technique that utilizes not only a temporal change of gray levels but also a spatial edge intensity of motion pictures, is proposed. The SELAO method is a software video‐processing technology to improve motion‐picture quality rendered on LCDs more than is possible with a conventional SLAO method without edge‐adaptive overdrive, and it works in real time on commonly used personal computers (PCs). 相似文献
95.
The Video Server Estimator (VSE) is an analytical tool which allows a user to perform a cost/performance analysis of video servers with hierarchical storage. The underlying model comprises multiple systems, main memory, expanded storage, disks and a tape library. The main objective of the tool is to optimally allocate the video files to different storage media based on the system parameters and the video file request probability distribution. The cost and the size of the video server that can accommodate a customer profile are determined. Furthermore, the impact of design parameters on the cost and performance are examined through a parametric analysis. 相似文献
96.
本文介绍ISDN的基本概念 ,中国ISDN业务飞速发展的状况。并结合实际 ,着重讨论了ISDN与电视会议系统、ISDN与Internet的接入等当今ISDN应用最广泛的业务。 相似文献
97.
J. A. LYNCH H. J. H. MACFIE† G. C. MEAD‡ 《International Journal of Food Science & Technology》1991,26(6):653-668
A panel of experienced assessors was used to test the effect of irradiation at 2.5kGy (250krad) on the sensory quality of 1-day and 21-day-old turkey breast fillets stored at 1°C in either oxygen-permeable polythene or an oxygen-impermeable barrier film. In the application of Free Choice Profiling and Generalized Procrustes Analysis, assessors used their own terms to describe the appearance, odour and flavour of the samples.
The irradiated samples showed negligible growth of micro-organisms across 21 days of storage. Radiation treatment resulted in an intense pink colour in the raw and cooked samples, which was maintained during storage in oxygen-impermeable film, but decreased in samples exposed to oxygen during storage. Radiation also produced a set of unpleasant raw odour notes variously described as sour, rancid, mature, bad meat or putrid in the samples stored in oxygen-impermeable film. These notes were unlike the sulphurous notes previously associated with protein denaturation in irradiated chicken and were apparently distinct from the odour notes that developed in corresponding non-irradiated samples. 相似文献
The irradiated samples showed negligible growth of micro-organisms across 21 days of storage. Radiation treatment resulted in an intense pink colour in the raw and cooked samples, which was maintained during storage in oxygen-impermeable film, but decreased in samples exposed to oxygen during storage. Radiation also produced a set of unpleasant raw odour notes variously described as sour, rancid, mature, bad meat or putrid in the samples stored in oxygen-impermeable film. These notes were unlike the sulphurous notes previously associated with protein denaturation in irradiated chicken and were apparently distinct from the odour notes that developed in corresponding non-irradiated samples. 相似文献
98.
T. R. Black 《Journal of Computer Assisted Learning》1987,3(4):204-213
Abstract In the past, authoring systems have been used to generate computer-assisted learning materials that have often followed the rather restrictive programmed learning format. A number of innovative ways of using recently developed systems to develop CAL packages that include a wider range of learning activities (access to data bases, simulations, interactive video, etc.) are described. Analogous to the concept of a media selection model, a computer delivery mode selection model is presented as an aid to decision making for designers. This increase in flexibility should broaden the applicability of computerassisted learning (CAL) to a wider range of educational objectives and raise the level of the cognitive emphasis in learning packages, as well as facilitate the implementation of visually appealing materials. The paper also implies a standard of acceptability for authoring systems. 相似文献
99.
Information Visualization Within a Digital Video Library 总被引:1,自引:0,他引:1
The Informedia Digital Video Library contains over a thousand hours of video, consuming over a terabyte of disk space. This paper summarizes the multimedia abstractions used to represent this video in prior systems and introduces the visualization techniques employed to browse and navigate multiple video documents at once. 相似文献
100.
Modified Atmosphere Packaging Affects Ascorbic Acid, Enzyme Activity and Market Quality of Broccoli 总被引:1,自引:0,他引:1
Reduced ascorbic acid (RAA) content, total chlorophyll and green color retention, enzyme activities and texture changes were followed in broccoli spears packaged in polymeric film and nonpackaged during 96 hr storage (10°C). Concentrations within packages monitored by gas chromatography were (CO2,) 8% and (02) 10%. RAA retention, moisture content, total chlorophyll and color retention were greater in packaged broccoli. No differences were found between packaged and nonpackaged broccoli for ascorbate oxidase and peroxidase activities, or texture. 相似文献