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福建平潭岛红色风沙色变机理探讨
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作者 俞鸣同 王茜 《亚热带资源与环境学报》 2018年第3期1-8,共8页
平潭岛流水老红砂具有显著的红色、黄色色变现象。采集流水剖面27个样品,做粒度、电导率、色度、光谱等分析,研究表明:红色沙具有高红度值(a)、高黄度值(b)、低亮度值(L)的特点,而黄色沙a值低、b值低、L值高,色度参数a值和b值与红色的... 平潭岛流水老红砂具有显著的红色、黄色色变现象。采集流水剖面27个样品,做粒度、电导率、色度、光谱等分析,研究表明:红色沙具有高红度值(a)、高黄度值(b)、低亮度值(L)的特点,而黄色沙a值低、b值低、L值高,色度参数a值和b值与红色的赤铁矿和黄色的针铁矿有关,红化是含铁硅酸盐矿物风化生成的针铁矿,在暖干气候下脱水转化成赤铁矿,使黏土和石英砂粒染红色;黄化或褪色是赤铁矿在相对湿润的气候条件下发生复杂的化学反应形成针铁矿,使沉积物呈黄色或褪色。红色沙和黄色沙交错反映了流水剖面的形成环境具有明显的干湿变化。 展开更多
关键词 风沙沉积 色度变化 气候变化
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基于人脸视频的心率检测研究综述 被引量:3
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作者 欧卫华 陈龙保 《贵州师范大学学报(自然科学版)》 CAS 2021年第4期10-20,F0003,共12页
心率是反应人体生理状态的重要指标。目前,以接触式为主流的心率检测方法需要直接皮肤接触,无法进行远程测量,易导致不卫生、不舒适等问题。近年来,基于远程光学体积描记术(Remote photoplethysmography,rPPG)的心率检测方法受到广泛关... 心率是反应人体生理状态的重要指标。目前,以接触式为主流的心率检测方法需要直接皮肤接触,无法进行远程测量,易导致不卫生、不舒适等问题。近年来,基于远程光学体积描记术(Remote photoplethysmography,rPPG)的心率检测方法受到广泛关注,该方法无须接触即可远程测量,解决了不卫生、不舒适等问题。介绍了人脸视频心率检测的背景;总结了通过人脸视频进行心率检测的基本原理和一般流程;归纳了目前主流的检测方法、常用数据集和评价指标,并从兴趣区域(ROI)的选取、滤波去噪方法和心率信号分离算法等方面进行了实验比较;最后指出了该方向存在的问题及未来研究趋势。 展开更多
关键词 远程光学体积描记术 人脸视频 心率检测 色度变化
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Response of Ecosystem Service Value Based on Land Use Changes and Analysis of its Driving Factors in Typical Hilly Region with Red Soil 被引量:6
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作者 邹金浪 王金政 +1 位作者 王鹏 乐文年 《Agricultural Science & Technology》 CAS 2010年第11期150-154,共5页
The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation w... The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation was employed to explore the contribution level of the indicators such as total population,urbanization level,proportion of primary industry and investment of social fixed assets on ecosystem service value,and the correlation analysis was also carried out.The results showed that the ecosystem service value in Xingguo County during 1996-2005 mainly was woodland,and the decrease of woodland area was the major reason for the sustained reduction of ecosystem service value.With the further increase of market demand and the incentives of local government,the garden area rapidly increased during 2001-2005,and the influence degree of garden towards the changes of ecosystem service value was only second to woodland,ranking No.2.Four socio-economic indicators had different correlation degree with ecosystem service value during the different research periods.Total population,urbanization level and proportion of primary industry had high correlation degree with ecosystem service value,whereas the influence degree of various socio-economic indicators on ecosystem service value was equal with each other day by day.Urbanization level,investment of social fixed assets and total population had significant negative correlation with ecosystem service value,while the proportion of primary industry had positive correlation with ecosystem service value. 展开更多
关键词 Ecosystem service value Land use change Gray correlation analysis Driving factor Hilly region with red soil
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新型路面雾封层材料耐久性能试验研究 被引量:2
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作者 李佳宁 张新天 《中国市政工程》 2022年第6期82-85,126,共5页
沥青路面在使用过程中,不仅会受到车辆荷载的重复作用,还会受到水温条件等环境因素影响,导致路面产生裂缝、车辙变形、表层材料松散脱落等损害,雾封层技术可有效修复沥青路面的各种初期病害。常规雾封层材料多为乳化沥青,表现出耐久性... 沥青路面在使用过程中,不仅会受到车辆荷载的重复作用,还会受到水温条件等环境因素影响,导致路面产生裂缝、车辙变形、表层材料松散脱落等损害,雾封层技术可有效修复沥青路面的各种初期病害。常规雾封层材料多为乳化沥青,表现出耐久性不足、使用性能难以保持良好状态等缺陷。与常规雾封层相比,水性环氧改性丙烯酸为主要原材料的新型雾封层在抗滑性、耐磨性、抗渗性、抗水侵损害和抗老化性能等多方面具有优势。通过模拟温度、浸水、紫外线老化及行车荷载碾压条件,试验分析新型雾封层与常规雾封层材料的耐久性差异,提出了基于路用性能与色度的雾封层耐久性试验评价方法。 展开更多
关键词 新型雾封层 水性环氧改性丙烯酸 环境条件模拟 色度变化 抗老化性能
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EFFECTIVE APPEARANCE MODEL FOR PROBABILISTIC OBJECT TRACKING 被引量:1
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作者 Wang Shupeng Ji Hongbing 《Journal of Electronics(China)》 2009年第4期503-508,共6页
This paper presents a robust object tracking approach via a spatially constrained colour model. Local image patches of the object and spatial relation between these patches are informative and stable during object tra... This paper presents a robust object tracking approach via a spatially constrained colour model. Local image patches of the object and spatial relation between these patches are informative and stable during object tracking. So, we propose to partition an object into patches and develop a Spatially Constrained Colour Model (SCCM) by combining the colour distributions and spatial configuration of these patches. The likelihood of the candidate object is given by estimating the confidences of the pixels in the candidate object region. The appearance model is learnt from the first frame and the tracking is carried out by particle filter. The experimental results show that the proposed tracking approach can accurately track the object with scale changes, pose variance and partial occlusion. 展开更多
关键词 Object tracking Appearance model Particle filter Adaptive scale
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Impacts of Global Warming Perturbation on Water Resources in Arid Zone: Case Study of Kaidu River Basin in Northwest China 被引量:6
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作者 MUPENZI Jean de la Paix 《Journal of Mountain Science》 SCIE CSCD 2011年第5期704-710,共7页
The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the p... The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the past 29 years from 1979 to 2007 were collected and analyzed using parametric and non-parametric methods, the connection between temperature and precipitation by the combination of grey correlation analysis method and the hypothesis testing for trend of climate change. The results show a high increase in temperature in the study area as well as an extreme and highly variable hydrological regime in this region, where flash floods can exceed the total runoff from a sequence of years. These variations may be due to the geographical location of the Kaidu River Basin in arid zone. It also reveals that precipitation has a much greater impact on stream flow than that of temperature. The development of new approaches was proposed as responses to climate change in this arid region. 展开更多
关键词 Global warming Kaidu River TEMPERATURE Precipitations Stream flow
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Effect of the Thickess on Color of Porcelain Laminate Veneer 被引量:1
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作者 陆支越 章非敏 殷新民 《Journal of Nanjing Medical University》 2003年第2期74-77,共4页
Objective : To evaluate the color change of the two-layer porcelain laminate veneer after adding veneering porcelain of different thickness to the 0. 2 mm thick aluminum oxide. Methods : Ten aluminum oxide disks were ... Objective : To evaluate the color change of the two-layer porcelain laminate veneer after adding veneering porcelain of different thickness to the 0. 2 mm thick aluminum oxide. Methods : Ten aluminum oxide disks were randomized into 2 groups. Each of five disks was veneered with Vita Lumin Shade 54 porcelain of thickness 0/0.4 mm and 0. 6 mm respectively. The L'a'b* color notations of the substrate covered with nan-veneered disks and 2 thickness porcelain veneered disks were measured separately and the color differences (AE) were calculated. Results ?Statistically significant differences in color coordinates of dark substrates were recorded after the substrate was covered by an aluminum oxide disk and also after the addition of veneering porcelain to the aluminum oxide disks in group 1 (P=0. 000 2) and group 2(P=0. 007 5) and between 2 groups (P=0. 000 1). Conclusion -The ability of masking underlying discoloration was increased and shifted to gray when the thickness of veneering porcelain increased. 展开更多
关键词 porcelain laminate veneer thickness COLOR
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Retting of Musa sapientum Pseudostem with Pectin Decomposting Bacteria
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作者 H. Rasmina M. S. Naimah +2 位作者 H. Aziah Y. N. Kiew Y. Konami 《Journal of Agricultural Science and Technology(B)》 2011年第8期1238-1244,共7页
The upper and lower portions of Musa sapientum pseudo-stem sheaths were exposed in four types of treatments: pectin decomposing bacteria, magnesium oxide (MgO), both pectin decomposing bacteria and MgO and control.... The upper and lower portions of Musa sapientum pseudo-stem sheaths were exposed in four types of treatments: pectin decomposing bacteria, magnesium oxide (MgO), both pectin decomposing bacteria and MgO and control. The fibre strength properties were tested using SIRIM Standard methods and colour changed using gray scale. The bioaugmentation of pectin decomposing bacteria together with MgO additions were found to enhance retting process and reduced retting periods 52% and yielded better strength on the fibres. The lower portion pseudo-stem sheaths gave the higher strength than upper portion. Colour changed showed that the bioaugmentation of pectin bacteria enhanced the degradation colouring compound in banana fibres. 展开更多
关键词 Banana pseudo-stem banana fibre RETTING pectin decomposing bacteria catalyst MgO.
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Greenhouse Gases Trapping
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作者 Terpugov Daniil Terpugov Grigory 《Journal of Chemistry and Chemical Engineering》 2013年第1期50-55,共6页
Climate change is the main problem of mankind, especially because of it's increasing speed and by specialists' forecast the situation will become worse. Climatic changes are correlated with the degradation of biosph... Climate change is the main problem of mankind, especially because of it's increasing speed and by specialists' forecast the situation will become worse. Climatic changes are correlated with the degradation of biosphere. It is a question of saving life on authors planet. The authors should begin taking strong measures, else Earth has a chance to repeat the destiny of Mars and Venus, as some scientists are afraid of. So reasoning like "When will it be and will it be at all" is for lazy, careless and selfish people. Now, because of the industrial emission of greenhouse gases, the temperature of the atmosphere is growing, the climate is changing: sudden temperature differences, snowfalls where it used to be impossible, thickness of arctic ice decrease is about 40% (a great ice-hole has been found on the north pole), repetition of droughts has increased in 8 times, power of hurricanes-2 times, increased power of floods. This is the result of lack of foresight, over-materialism and greediness, unwillingness to see the consequences because of the momentary advantages. How it is possible to trap CO2, SO2 and other gases? Commercially gas purification at thermoelectric power stations, ferrous and non-ferrous metallurgy plants, cement and chemical plants is being made with filters and cyclones that trap solid parts, and using different absorptive and adsorptive methods. Unfortunately at present there is no effective method of COE trapping. 展开更多
关键词 Climate change greenhouse gases carbon dioxide trapping direct osmosis.
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Industrial Carbon Emissions Status and Analysis Based on Energy Consumption
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作者 Cao Zi Shen Zhenyao 《Chinese Journal of Population,Resources and Environment》 2011年第1期33-41,共9页
With frequent disastrous weathers and increasingly prominent GHG effects in recent years, normal existence and development of mankind are facing unprecedented threats and challenges. GHG emissions mitigation for the g... With frequent disastrous weathers and increasingly prominent GHG effects in recent years, normal existence and development of mankind are facing unprecedented threats and challenges. GHG emissions mitigation for the global climate changes has been the focus of concern of the world. As the biggest developing country and the second largest country of carbon-emission, China attaches importance to the carbon emission reduction. The major GHG component is carbon dioxide and in China, the emis- sion of carbon dioxide is mainly from industrial production. In the paper, the status and trend of Coz emission from industrial departments, high-carbon emission and its specific industries are shown in statistics. Meanwhile, the policy environment, industrial organization structure and technology of carbon high emission are all discussed based on practical situations in these departments and industries. At the end, through the analysis of gray correlation, correlativity is explored for both fossil energy consumption and total carbon emission, and also for the production value and carbon emission of each industrial sector. Some policy proposals for the establishment of low-carbon industries and transition of economic development pattern are set forth. 展开更多
关键词 industrial carbon emissions carbon intensity gray correlation emission reduction approach
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The dynamics of color signals in male threespine sticklebacks Gasterosteus aculeatus 被引量:4
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作者 Meike HIERMES Ingolf P. RICK +1 位作者 Marion MEHLIS Theo C. M. BAKKER 《Current Zoology》 SCIE CAS CSCD 2016年第1期23-31,共9页
Body coloration and color patterns are ubiquitous throughout the animal kingdom and vary be- tween and within species. Recent studies have dealt with individual dynamics of various aspects of coloration, as it is in m... Body coloration and color patterns are ubiquitous throughout the animal kingdom and vary be- tween and within species. Recent studies have dealt with individual dynamics of various aspects of coloration, as it is in many cases a flexible trait and changes in color expression may be context-de- pendent. During the reproductive phase, temporal changes of coloration in the visible spectral range (400-700 nm) have been shown for many animals but corresponding changes in the ultravio- let (UV) waveband (300-400 nm) have rarely been studied. Threespine stickleback Gasterosteus aculeatus males develop conspicuous orange-red breeding coloration combined with UV reflect- ance in the cheek region. We investigated dynamics of color patterns including UV throughout a male breeding cycle, as well as short-term changes in coloration in response to a computer- animated rival using reflectance spectrophotometry and visual modeling, to estimate how colors would be perceived by conspecifics. We found the orange-red component of coloration to vary during the breeding cycle with respect to hue (theta/R50) and intensity (achieved chroma/red chroma). Furthermore, color intensity in the orange-red spectral part (achieved chroma) tended to be increased after the presentation of an artificial rival. Dynamic changes in specific measures of hue and intensity in the UV waveband were not found. In general, the orange-red component of the signal seems to be dynamic with respect to color intensity and hue. This accounts in particular for color changes during the breeding cycle, presumably to signal reproductive status, and with limitations as well in the intrasexual context, most likely to signal dominance or inferiority. 展开更多
关键词 breeding season color change color signals STICKLEBACK structural coloration UV coloration
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Design and synthesis by redox polymerization of a bio-based carboxylic elastomer for green tire 被引量:5
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作者 Xinxin Zhou Runguo Wang +5 位作者 Weiwei Lei He Qiao Haoling Ji Liqun Zhang Kuo-Chih Hua Joseph Kulig 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第10期1561-1569,共9页
Poly(dibutyl itaconate-co-isoprene-co-methacrylic acid)(PDIM) elastomer was designed and synthesized by redox emulsion polymerization under mild conditions. PDIM has high molecular weight, relatively high yield, and l... Poly(dibutyl itaconate-co-isoprene-co-methacrylic acid)(PDIM) elastomer was designed and synthesized by redox emulsion polymerization under mild conditions. PDIM has high molecular weight, relatively high yield, and low glass transition temperature(Tg). The structure of PDIM was determined by FTIR and NMR, and the carboxyl content was obtained by titration in a non-proton solvent. Tensile strength and elongation at break increased with increasing carboxyl content. In addition, the interaction between PDIM and silica was elucidated by rubber process analyzer(RPA) and TEM, and the results showed that the silica-PDIM interaction was strong, but the silica-silica interaction was weak. 展开更多
关键词 carboxylic rubber bio-based elastomer SYNTHESIS redox polymerozation green tire
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Analysis of Generalized Ghost Dark Energy in LQC and Galileon Gravity
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作者 mahasweta biswas ujjal debnath 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第1期121-126,共6页
A so-called ghost dark energy was recently proposed to explain the present acceleration of the universe.The energy density of ghost dark energy,which originates from Veneziano ghost of Quantum Chromodynamics(QCD),in a... A so-called ghost dark energy was recently proposed to explain the present acceleration of the universe.The energy density of ghost dark energy,which originates from Veneziano ghost of Quantum Chromodynamics(QCD),in a time dependent background,can be written in the form,ρD=αH + βH^2 where H is the Hubble parameter.We investigate the generalized ghost dark energy(GGDE) model in the setup of loop quantum Cosmology(LQC) and Galileon Cosmology.We study the cosmological implications of the models.We also obtain the equation of state and the deceleration parameters and differential equations governing the evolution of this dark energy model for LQC and Galileon Cosmology. 展开更多
关键词 ghost dark energy loop equation cosmology Galileon gravity
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