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彩色测温方法中物体辐射色域的界定和划分

王安全,程晓舫,陆少松

《中国工程科学》 2002年 第4卷 第8期   页码 54-57

摘要:

介绍了彩色测温方法的基本原理,并基于可见光波段内光谱发射率的线性模型给出物体辐射颜色色品的表述;明确了一个色品最多只能求解出两个温度;解决了彩色测温方法中物体辐射色域的界定问题,并将辐射色域划分为温度单解域和双解域。

关键词: 辐射测温     彩色测温     色域     发射率    

我国海洋水色遥感应用工程技术的新进展

潘德炉,白雁

《中国工程科学》 2008年 第10卷 第9期   页码 14-24

摘要:

介绍了近年来我国在海洋水色遥感应用工程技术方面的新进展,包括以应用为导向的关键技术研究和各类应用示范系统的开发等。针对当前海洋水色遥感业务化应用服务所面临的问题和一些急需解决的关键工程技术进行了分析和展望。

关键词: 海洋水色遥感     业务化应用     中国海洋一号卫星    

An optimized solar-air degree-day method to evaluate energy demand for poultry buildings in different climate zones

Yang WANG, Baoming LI

《农业科学与工程前沿(英文)》 2020年 第7卷 第4期   页码 478-489 doi: 10.15302/J-FASE-2019289

摘要:

The degree-day method is widely used to determine energy consumption but cannot be directly applied to poultry buildings without improvements in its accuracy. This study was designed to optimize the degree-day calculation and proposes a solar-air degree-day method, which can be used to calculate the cooling and heating degree-days and the annual cooling and heating loads under different climate conditions for poultry buildings. In this paper, the solar-air degree-day method was proposed, which considers the effects of solar radiation with different wall orientations and surface colors. Five Chinese cities, Harbin, Beijing, Chongqing, Kunming and Guangzhou, were selected to represent different climate zones to determine the solar-air degree-days. The heating and cooling energy requirements for different climates were compared by DeST (Designer’s Simulation Toolkit) simulation and the solar-air degree-day method. Approaches to decrease energy consumption were developed. The results showed that the maximum relative error was less than 10%, and the new method was not significantly different from the DeST simulation ( >0.05). The accuracy of calculating energy requirements was improved by the solar-air degree-day method in the different climate zones. Orientation and surface color effects on energy consumption need to be considered, and external walls of different orientations should have different surface colors.

关键词: base temperature     energy consumption     solar radiation     orientation     surface color    

Investigations on color variations of Morpho rhetenor butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 394-400 doi: 10.1007/s11465-012-0347-y

摘要:

Experiments and simulations are carried out to investigate the optical properties of butterfly wing scales. The upper surface of a male butterfly wing presents a single-layer of scales, the microstructures of which are responsible for the brilliant blue color. The color varies from cyan blue to yellow green and soon afterwards returns back to cyan blue when some ethanol is dropped on the upper surface. At the start of the ethanol volatilization process, the reflection spectrum remains stable. As the ethanol further volatilizes, the peak reflectance decreases slightly, then increases dramatically. Meanwhile, the peak wavelength keeps approximately constant, then decreases, and keeps almost stable at the end of the process. Therefore, the optical properties depend strongly on the varying ambient conditions, including the refractive index and the thickness of the packing medium. Moreover, the possible causes for the scales in dark green region after several dropping ethanol experiments are clarified. This research benefits our understanding of the color variation mechanisms of the wing scales, and provides inspiration for further studies and applications.

关键词: Morpho rhetenor     microstructures     color variations     ambient medium    

Multi-color space threshold segmentation and self-learning k-NN algorithm for surge test EUT status

Jian HUANG,Gui-xiong LIU

《机械工程前沿(英文)》 2016年 第11卷 第3期   页码 311-315 doi: 10.1007/s11465-016-0376-z

摘要:

The identification of targets varies in different surge tests. A multi-color space threshold segmentation and self-learning k-nearest neighbor algorithm (k-NN) for equipment under test status identification was proposed after using feature matching to identify equipment status had to train new patterns every time before testing. First, color space (L*a*b*, hue saturation lightness (HSL), hue saturation value (HSV)) to segment was selected according to the high luminance points ratio and white luminance points ratio of the image. Second, the unknown class sample Sr was classified by the k-NN algorithm with training set Tz according to the feature vector, which was formed from number of pixels, eccentricity ratio, compactness ratio, and Euler’s numbers. Last, while the classification confidence coefficient equaled k, made Sr as one sample of pre-training set Tz′. The training set Tz increased to Tz+1 by Tz′ if Tz′ was saturated. In nine series of illuminant, indicator light, screen, and disturbances samples (a total of 21600 frames), the algorithm had a 98.65% identification accuracy, also selected five groups of samples to enlarge the training set from T0 to T5 by itself.

关键词: multi-color space     k-nearest neighbor algorithm (k-NN)     self-learning     surge test    

高等植物叶片色域的理论研究

程晓舫,董金一,范学良,丁金磊

《中国工程科学》 2006年 第8卷 第12期   页码 66-69

摘要:

利用叶绿素和类胡萝卜素的经典吸收光谱以及植物叶片中不含色素的其他物质成分的光谱,分别求得其在CIE1931色品图中的理论坐标,并根据色度学中的加法混色原理确定出高等植物叶色的理论域范围。实验数据与理论相吻合。

关键词: 高等植物     色素     吸收光谱     色度坐标     色域    

固态照明系统中颜色维持率的研究进展 Review

Maryam Yazdan Mehr, Willem Dirk van Driel, 张国旗

《工程(英文)》 2015年 第1卷 第2期   页码 170-178 doi: 10.15302/J-ENG-2015035

摘要:

本文全面回顾了固态照明 (SSL) 系统中颜色维持率 (也称颜色漂移) 的研究进展。首先介绍了颜色漂移及实际生产工艺中的颜色漂移实例,然后阐释了固态照明系统中不同部分的老化机制。通过对LED 产品中透镜/密封件所用的各种材料的介绍, 探讨了这些材料对颜色漂移的促进作用。本文还就行业对光通维持率的定义标准化、表征描述与预测所做的工作进行了简单的回顾。

关键词: LED,颜色漂移,光通量衰减,流明衰减    

Anefficient quadrature demodulator for medical ultrasound imaging

Hao ZHOU,Yin-fei ZHENG

《信息与电子工程前沿(英文)》 2015年 第16卷 第4期   页码 301-310 doi: 10.1631/FITEE.1400205

摘要: Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency (RF) signal. In quadrature demodulation, RF signal is multiplied with the sine and cosine wave reference signal and then low-pass filtered to produce the base-band complex signal, which has high computational complexity. In this paper, we propose an efficient quadrature demodulation method for B-mode and color flow imaging, in which the RF signal is demodulated by a pair of finite impulse response filters without mixing with the reference signal, to reduce the computational complexity. The proposed method was evaluated with simulation and in vivo experiments. From the simulation results, the proposed quadrature demodulation method produced similar normalized residual sum of squares (NRSS) and velocity profile compared with the conventional quadrature demodulation method. In the in vivo color flow imaging experiments, the time of the demodulation process was 5.66 ms and 3.36 ms, for the conventional method and the proposed method, respectively. These results indicated that the proposed method can maintain the performance of quadrature demodulation while reducing computational complexity.

关键词: B-mode ultrasound imaging     Color flow imaging     Quadrature demodulation     Finite impulse response filter    

Combination of ARTP mutagenesis and color-mediated high-throughput screening to enhance 1-naphthol yield

Chenggang Qiu, Alei Zhang, Sha Tao, Kang Li, Kequan Chen, Pingkai Ouyang

《化学科学与工程前沿(英文)》 2020年 第14卷 第5期   页码 793-801 doi: 10.1007/s11705-019-1876-2

摘要: Strain QCG of the aerobic bacteria is capable of producing 1-naphthol from naphthalene, this strain was first isolated and characterized in this study. Strain QCG was mutagenized to enhance 1-naphthol production, using atmospheric and room temperature plasma (ARTP) technology. Then, a microbial clone screening system was used to accelerate the operation. Meanwhile, a novel color-mediated high-throughput screening using 4-aminoantipyrine was performed to screen mutants. The optimal mutant strain QCG4 produced 19.58±0.34 mg∙L 1-naphthol from naphthalene that was 47.32% higher than that of the original strain (13.29±0.28 mg∙L ). In addition, the optimal conditions for 1-naphthol production via whole-cell catalysis of strain QCG4 were determined to be an OD of 40, 150 mg∙L naphthalene, and 7.5% dimethyl formamide as a co-solvent at pH 7.5 and 26°C for 3 h, resulting in 41.18±0.12 mg∙L 1-naphthol, i.e., the mutant strain produces a 2.1-fold higher yield compared to the original strain.

关键词: Bacillus cereus QCG     naphthalene     1-naphthol     ARTP mutagenesis     high-throughput screening     4-aminoantipyrine    

Genomic regions under selection for important traits in domestic horse breeds

Xuexue LIU, Yuehui MA, Lin JIANG

《农业科学与工程前沿(英文)》 2017年 第4卷 第3期   页码 289-294 doi: 10.15302/J-FASE-2017155

摘要: Horses were domesticated 5500 years ago, thousands of years later than other domestic animals; however, in this relatively short period, domestic horses have had a great impact on human history by accelerating civilization, revolutionizing warfare and advancing agricultural production. Modern breeding using marker-assisted selection has greatly accelerated breeding progress. Therefore, identification of genetic markers underlying the traits of interest in domestic horses is the basis for the modern breeding system. In this review, we present an overview of genetic mapping studies and genome wide analyses to identify the genomic regions targeted by positive selection for four important aspects of horses, coat color, racing performance, gait and height at withers. The locus, for example, has been shown to be the main gene responsible for chestnut color, and the locus has been shown to control the muscle fiber growth in racing breeds. The missense mutation in is the causal mutation for the alternate gaits in horses. Height at withers, a quantitative trait, was mapped to four major loci (3:105547002, 6:81481064, 9:75550059 and 11:232597 32) that can explain 83% of the height variations in domestic horses.

关键词: horse     coat color     racing performance     gait     height    

Cell surface protein engineering for high-performance whole-cell catalysts

Hajime Nakatani,Katsutoshi Hori

《化学科学与工程前沿(英文)》 2017年 第11卷 第1期   页码 46-57 doi: 10.1007/s11705-017-1609-3

摘要: Cell surface protein engineering facilitated by accumulation of information on genome and protein structure involves heterologous production and modification of cell surface proteins using genetic engineering, and is important for the development of high-performance whole-cell catalysts. In this field, cell surface display is a major technology by exposing target proteins, such as enzymes, on the cell surface using a carrier protein. The target proteins are fused to the carrier proteins that transport and tether them to the cell surface, as well as to a secretion signal. This paper reviews cell surface display systems for prokaryotic and eukaryotic cells from the perspective of carrier proteins, which determine the number of displayed molecules, and the localization, size, and direction ( or terminal anchoring) of the passengers. We also discuss advanced methods for displaying multiple enzymes and a new method for the immobilization of whole-cell catalysts using adhesive surface proteins.

关键词: cell surface engineering     surface display     whole-cell catalysts     bioprocess    

An Exploration of Surface Integrity Remanufacturing for Aeroengine Components

Qiao Xiang,Yong He,Ting-hong Hou

《工程管理前沿(英文)》 2016年 第3卷 第2期   页码 107-114 doi: 10.15302/J-FEM-2016025

摘要: Surface integrity is the major factor impacting on the operation quality, service life and reliability of the aeroengine components. The surface integrity of aeroengine component is damaged by the failures such as crack, deformation, oxidation, corrosion, erosion, and microstructural degeneration. It adopts advanced remanufacturing technologies to restore or improve the surface integrity and regenerate these high value parts. This paper firstly puts forward the concept, namely surface integrity remanufacturing for aeroengine components, and its connotation. The key remanufacturing technologies have been developed to repair the components with surface damages. Ultimately, some application examples of surface integrity remanufacturing technologies as well as their effects in aeroengine maintenance are introduced. The discarded components have been reused and their service lives have been extended and their reliability has been increased by implementing surface integrity remanufacturing. It has realized “The Repaired Components Outpacing the New Ones”, material saving, energy saving, and emission reduction.

关键词: aeroengine component     surface integrity     remanufacturing     surface integrity remanufacturing    

Review on mechanism and process of surface polishing using lasers

Arun KRISHNAN, Fengzhou FANG

《机械工程前沿(英文)》 2019年 第14卷 第3期   页码 299-319 doi: 10.1007/s11465-019-0535-0

摘要: Laser polishing is a technology of smoothening the surface of various materials with highly intense laser beams. When these beams impact on the material surface to be polished, the surface starts to be melted due to the high temperature. The melted material is then relocated from the ‘peaks to valleys’ under the multidirectional action of surface tension. By varying the process parameters such as beam intensity, energy density, spot diameter, and feed rate, different rates of surface roughness can be achieved. High precision polishing of surfaces can be done using laser process. Currently, laser polishing has extended its applications from photonics to molds as well as bio-medical sectors. Conventional polishing techniques have many drawbacks such as less capability of polishing freeform surfaces, environmental pollution, long processing time, and health hazards for the operators. Laser polishing on the other hand eliminates all the mentioned drawbacks and comes as a promising technology that can be relied for smoothening of initial topography of the surfaces irrespective of the complexity of the surface. Majority of the researchers performed laser polishing on materials such as steel, titanium, and its alloys because of its low cost and reliability. This article gives a detailed overview of the laser polishing mechanism by explaining various process parameters briefly to get a better understanding about the entire polishing process. The advantages and applications are also explained clearly to have a good knowledge about the importance of laser polishing in the future.

关键词: laser polishing     surface roughness     process parameters     mechanism    

Tribological study on the surface modification of metal-on-polymer bioimplants

《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0682-6

摘要: The tribological performance of artificial joints is regarded as the main factor of the lifespan of implanted prostheses. The relationship between surface roughness and coefficient of friction (COF) under dry and lubricated conditions is studied. Results show that under dry test, friction coefficient is not reduced all the time with a decrease in surface roughness. On the contrary, a threshold of roughness value is observed, and frictional force increases again below this value. This critical value lies between 40 and 100 nm in Sa (roughness). This phenomenon is due to the transfer of friction mechanisms from abrasion to adhesion. Under wet test, COF always decreases with reduction in surface roughness. This result is mainly attributed to the existence of a thin layer of lubricant film that prevents the intimate contact of two articulating surfaces, thus greatly alleviating adhesion friction. Furthermore, surface texturing technology is successful in improving the corresponding tribological performance by decreasing friction force and mitigating surface deterioration. The even-distribution mode of texturing patterns is most suitable for artificial joints. By obtaining the optimal surface roughness and applying texturing technology, the tribological performance of polymer-based bioimplants can be greatly enhanced.

关键词: artificial joints     surface roughness     friction     surface texturing    

Development of surface reconstruction algorithms for optical interferometric measurement

Dongxu WU, Fengzhou FANG

《机械工程前沿(英文)》 2021年 第16卷 第1期   页码 1-31 doi: 10.1007/s11465-020-0602-6

摘要: Optical interferometry is a powerful tool for measuring and characterizing areal surface topography in precision manufacturing. A variety of instruments based on optical interferometry have been developed to meet the measurement needs in various applications, but the existing techniques are simply not enough to meet the ever-increasing requirements in terms of accuracy, speed, robustness, and dynamic range, especially in on-line or on-machine conditions. This paper provides an in-depth perspective of surface topography reconstruction for optical interferometric measurements. Principles, configurations, and applications of typical optical interferometers with different capabilities and limitations are presented. Theoretical background and recent advances of fringe analysis algorithms, including coherence peak sensing and phase-shifting algorithm, are summarized. The new developments in measurement accuracy and repeatability, noise resistance, self-calibration ability, and computational efficiency are discussed. This paper also presents the new challenges that optical interferometry techniques are facing in surface topography measurement. To address these challenges, advanced techniques in image stitching, on-machine measurement, intelligent sampling, parallel computing, and deep learning are explored to improve the functional performance of optical interferometry in future manufacturing metrology.

关键词: surface topography     measurement     optical interferometry     coherence envelope     phase-shifting algorithm    

标题 作者 时间 类型 操作

彩色测温方法中物体辐射色域的界定和划分

王安全,程晓舫,陆少松

期刊论文

我国海洋水色遥感应用工程技术的新进展

潘德炉,白雁

期刊论文

An optimized solar-air degree-day method to evaluate energy demand for poultry buildings in different climate zones

Yang WANG, Baoming LI

期刊论文

Investigations on color variations of Morpho rhetenor butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

期刊论文

Multi-color space threshold segmentation and self-learning k-NN algorithm for surge test EUT status

Jian HUANG,Gui-xiong LIU

期刊论文

高等植物叶片色域的理论研究

程晓舫,董金一,范学良,丁金磊

期刊论文

固态照明系统中颜色维持率的研究进展

Maryam Yazdan Mehr, Willem Dirk van Driel, 张国旗

期刊论文

Anefficient quadrature demodulator for medical ultrasound imaging

Hao ZHOU,Yin-fei ZHENG

期刊论文

Combination of ARTP mutagenesis and color-mediated high-throughput screening to enhance 1-naphthol yield

Chenggang Qiu, Alei Zhang, Sha Tao, Kang Li, Kequan Chen, Pingkai Ouyang

期刊论文

Genomic regions under selection for important traits in domestic horse breeds

Xuexue LIU, Yuehui MA, Lin JIANG

期刊论文

Cell surface protein engineering for high-performance whole-cell catalysts

Hajime Nakatani,Katsutoshi Hori

期刊论文

An Exploration of Surface Integrity Remanufacturing for Aeroengine Components

Qiao Xiang,Yong He,Ting-hong Hou

期刊论文

Review on mechanism and process of surface polishing using lasers

Arun KRISHNAN, Fengzhou FANG

期刊论文

Tribological study on the surface modification of metal-on-polymer bioimplants

期刊论文

Development of surface reconstruction algorithms for optical interferometric measurement

Dongxu WU, Fengzhou FANG

期刊论文