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Study on the Photosynthetic Characteristics of Six Varieties(Strains)in Chinese Chestnut
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作者 Lizhi FU Yong YANG +6 位作者 Xiaoxiao KANG Meng WANG Jing LIU Xuan WANG Dongsheng WANG Liyang YU Hai’e ZHANG 《Agricultural Biotechnology》 2024年第1期9-14,57,共7页
[Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis effici... [Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis efficiency breeding and application in Chinese chestnut.[Methods]Six Chinese chestnut varieties of Castanea mollissima‘Yanbao’,C.mollissima‘Yanqiu’,C.mollissima‘Yanchang’,C.mollissima‘Yanjia’,C.mollissima‘Qianxi 37’,and C.mollissima‘Hybrid 22’were used as the materials.Using the portable photosynthesis system Li-6400,we measured the photosynthetic characteristics and diurnal variation of leaf samples of six different chestnut varieties or strains.We fitted the light response curves and photosynthetic parameters using the leaf floating model.Additionally,we determined the chlorophyll content in the leaves using a UV-visible spectrophotometer.[Results]Among the six chestnut varieties or strains,‘Yanqiu’exhibited a significantly higher photosynthetic light saturation point(P LSP)compared to other five varieties,and‘Hybrid 22’ranked second,indicating that these two varieties had the strongest adaptation to high light intensity.The photosynthetic light compensation point(P LCP)of‘Yanchang’was significantly higher than other five varieties,and"Qianxi 37"ranked second,indicating that these two varieties had the strongest adaptation to low light intensity.Additionally,they exhibited higher chlorophyll content and maintained good photosynthetic characteristics even in shaded environments with weak light stress.Varieties‘Yanbao’and‘Yanjia’showed higher P LSP and lower P LCP,indicating that these two varieties have a wider range of adaptation to light intensity.They were capable of efficiently utilizing light across a broader spectrum of intensities.‘Yanqiu’had the highest maximum net photosynthetic rate(P n,max)and the lowest dark respiration rate(R d),along with the highest chlorophyll content.It indicated that‘Yanqiu’has strong photosynthetic capacity and organic matter accumulation ability.It also had the highest P LSP,enabling it to fully utilize the high light environment of the Yanshan Mountains and possessed high light efficiency characteristics.The P n,max of‘Yanqiu’was significantly higher than other varieties.‘Hybrid 22’and‘Yanbao’also exhibited significantly higher P n,max compared with‘Yanjia’and‘Qianxi 37’.‘Yanchang’had the lowest P n,max.The order of P n,max among the six chestnut varieties or strains was as follows:‘Yanqiu’>‘Hybrid 22’>‘Yanbao’>‘Yanjia’>‘Qianxi 37’>‘Yanchang’.[Conclusions] 展开更多
关键词 Chinese chestnut Diurnal variation of photosynthesis light response model light response curve CHLOROPHYLL
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Research and Application of Caideng Model Rendering Technology for Virtual Reality
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作者 Xuefeng Wang Yadong Wu +1 位作者 Yan Luo Dan Luo 《Journal of Computer and Communications》 2024年第4期95-110,共16页
With the development of virtual reality (VR) technology, more and more industries are beginning to integrate with VR technology. In response to the problem of not being able to directly render the lighting effect of C... With the development of virtual reality (VR) technology, more and more industries are beginning to integrate with VR technology. In response to the problem of not being able to directly render the lighting effect of Caideng in digital Caideng scenes, this article analyzes the lighting model. It combines it with the lighting effect of Caideng scenes to design an optimized lighting model algorithm that fuses the bidirectional transmission distribution function (BTDF) model. This algorithm can efficiently render the lighting effect of Caideng models in a virtual environment. And using image optimization processing methods, the immersive experience effect on the VR is enhanced. Finally, a Caideng roaming interactive system was designed based on this method. The results show that the frame rate of the system is stable during operation, maintained above 60 fps, and has a good immersive experience. 展开更多
关键词 Virtual Reality Caideng Model lighting Model Point light Rendering
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Effect of green flickering light on myopia development and expression of M1 muscarinic acetylcholine receptor in guinea pigs 被引量:5
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作者 Yuan Tao Xiao-Li Li +3 位作者 Li-Yuan Sun Yu-Hua Wei Xiao-Ting Yu Hong Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第11期1755-1760,共6页
AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor(mAChR) M1 in the eyes of guinea pigs.METHODS: Thirty guinea pigs(15-20 days ... AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor(mAChR) M1 in the eyes of guinea pigs.METHODS: Thirty guinea pigs(15-20 days old) were randomly divided into three groups(n=10/group). Animals in group I were raised in a completely closed carton with green flickering light illumination. Those in group II were kept in the open top closed carton under normal natural light. Guinea pigs were raised in a sight-widen cage under normal natural light in group III. The refractive status and axial length were measured before and after 8 weeks' illumination. Moreover, total RNA extracted from retinal, choroidal, and scleral tissues were determined by real-time reverse transcription polymerase chain reaction(RT-PCR). The expressions of the receptor M1 were also explored in the retina, choroid, and sclera using immunohistochemistry.RESULTS: There was a remarkable reduction in refractive error and increase in axial length after 8-weeks' green flickering light stimulation(P〈0.001). The expression of M1 receptor mRNA in sclera and retina in myopia group were remarkably lower than that in group II and III(P〈0.01). Significant reduced expression of M1 receptor stimulated by green flickering light in retina and sclera tissues were also observed(P〈0.05). However, there was no M1 receptor expression in choroid in 3 groups.CONCLUSION: Myopia can be induced by 8 weeks' green flickering light exposure in the animal model. M1 receptor may be involved causally or protectively in myopia development. 展开更多
关键词 guinea pigs green flashing light myopia model muscarinic acetylcholine RECEPTOR
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Lighting Model of the Real World in Augmented Reality
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作者 周雅 闫达远 赵虎 《Journal of Beijing Institute of Technology》 EI CAS 2004年第2期165-168,共4页
Construction of a lighting model of the real world is one of the critical aims in an augmented reality (AR) system. The theory of lighting modeling used in computer graphics(CG) is applied in this study. The position... Construction of a lighting model of the real world is one of the critical aims in an augmented reality (AR) system. The theory of lighting modeling used in computer graphics(CG) is applied in this study. The position of the real light-source is first conjectured from light and shade of the registration image element by element using a ray tracking algorithm. Then the virtual light-source and virtual fiducial are constructed in the CG environment, in which, the Phong model is used to draw the light effect. By comparing the CG scene with the real image, one can modify the parameters of the lighting model over and over again, until the lighting effect of the CG scene is close enough to that of the real image. It is proved that this method works well in the indoor AR system. The method can be used feasibly in most applications with some improvements. 展开更多
关键词 augmented reality lighting model REGISTRATION
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Three-Dimentional Surface Light Irradiance Reconstruction in Bioluminescence Tomography
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作者 陈春晓 刘高 +3 位作者 张倩 李婷婷 王正盛 黎宁 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第6期652-659,共8页
Reconstruction of 3D surface irradiance distribution using multiple views captured by charged coupled device(CCD)camera is the basis of solving the light source in bioluminescence tomography(BLT).A simple and convenie... Reconstruction of 3D surface irradiance distribution using multiple views captured by charged coupled device(CCD)camera is the basis of solving the light source in bioluminescence tomography(BLT).A simple and convenient mapping technique based on the pin-hole imaging model and Lambert′s cosine law was presented to establish the relationship between gray levels and irradiance intensities.Compared with previous integrating sphere camera calibration used in BLT,the proposed method can effectively avoid heavy burden of simulation experiment to obtain the corresponding relationship of gray levels and irradiance intensities.The accuracy and feasibility of the proposed method are validated with no more than 1mm location error by different types of phantom experiments.The mapping approach is also applicable to other noncontact optical imaging system. 展开更多
关键词 light propagation model irradiance reconstruction bioluminescence tomography(BLT) pin-hole imaging
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Influence of plant architecture on maize physiology and yield in the Heilonggang River valley 被引量:11
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作者 Shoubing Huang Yingbo Gao +3 位作者 Yebei Li Lina Xu Hongbin Tao Pu Wang 《The Crop Journal》 SCIE CAS CSCD 2017年第1期52-62,共11页
The size and distribution of leaf area determine light interception in a crop canopy and influence overall photosynthesis and yield. Optimized plant architecture renders modern maize hybrids(Zea mays L.) more producti... The size and distribution of leaf area determine light interception in a crop canopy and influence overall photosynthesis and yield. Optimized plant architecture renders modern maize hybrids(Zea mays L.) more productive, owing to their tolerance of high plant densities. To determine physiological and yield response to maize plant architecture, a field experiment was conducted in 2010 and 2011. With the modern maize hybrid ZD958, three plant architectures, namely triangle, diamond and original plants, were included at two plant densities, 60,000 and 90,000 plants ha-1. Triangle and diamond plants were derived from the original plant by spraying the chemical regulator Jindele(active ingredients,ethephon, and cycocel) at different vegetative stages. To assess the effects of plant architecture, a light interception model was developed. Plant height, ear height, leaf size,and leaf orientation of the two regulated plant architectures were significantly reduced or altered compared with those of the original plants. On average across both plant densities and years, the original plants showed higher yield than the triangle and diamond plants,probably because of larger leaf area. The two-year mean grain yield of the original and diamond plants were almost the same at 90,000 plants ha-1(8714 vs. 8798 kg ha-1). The yield increase(up to 5%) of the diamonds plant at high plant densities was a result of increased kernel number per ear, which was likely a consequence of improved plant architecture in the top and middle canopy layers. The optimized light distribution within the canopy can delay leaf senescence, especially for triangle plants. The fraction of incident radiation simulated by the interception model successfully reflected plant architecture traits. Integration of canopy openness is expected to increase the simulation accuracy of the present model. Maize plant architecture with increased tolerance of high densities is probably dependent on the smaller but flatter leaves around the ear. 展开更多
关键词 MAIZE light interception YIELD light interception model Leaf senescence
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Agricultural Load Modeling Based on Crop Evapotranspiration and Light Integration for Economic Operation of Greenhouse Power Systems 被引量:2
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作者 Zeming Li Junyong Liu +2 位作者 Yue Xiang Xin Zhang Yanxin Chai 《CSEE Journal of Power and Energy Systems》 SCIE CSCD 2021年第5期1113-1121,共9页
The threat of environmental degradation attracts great attention to clean energy production and transportation.However,the limited scope of energy consumption causes the large-scale of clean energy sources to be aband... The threat of environmental degradation attracts great attention to clean energy production and transportation.However,the limited scope of energy consumption causes the large-scale of clean energy sources to be abandoned in Sichuan province.In the meantime,the development of modern greenhouse cultivation has transformed the agriculture industry to develop a brand-new type of electrical load in the grid.Consequently,the agricultural load can be used to consume the clean energy while facilitating plant growth.In this paper,an innovative agricultural load model is proposed based on crop evapotranspiration and daily light integration.Furthermore,the proposed agricultural load model is also applied to investigate the electricity consumption of five types of crop planting.The results illustrate that the power consumption is primarily driven by an artificial lighting compensation system. 展开更多
关键词 Agriculture load model crop evapotranspiration model daily light integration model power consumption
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The impacts of climate change on hydrology in a typical glacier region A case study in Hailuo Creek watershed of Mt.Gongga in China
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作者 GuoFeng Zhu YuanQing He +4 位作者 DaHe Qin HongKai Gao Tao Pu DongDong Chen Kai Wang 《Research in Cold and Arid Regions》 CSCD 2016年第3期227-240,共14页
The glaciers of the Hengduan Mountains play an important role in the hydrology processes of this region. In this study, the HBV Light model, which relies on a degree-day model to simulate glacier melting, was employed... The glaciers of the Hengduan Mountains play an important role in the hydrology processes of this region. In this study, the HBV Light model, which relies on a degree-day model to simulate glacier melting, was employed to simulate both glacier runoffand total runoff. The daily temperature and precipitation at the Hailuo Creek No. 1 Glacier from 1952 to 2009 were obtained from daily meteorological observed data at the glacier and from six national meteorological stations near the Hailuo Creek Basin. The daily air temperature, precipitation, runoff depth, and monthly potential evaporation in 1995, 1996, and 2002 were used to obtain a set of optimal parameters, and the annual total runoff and glacier runoff of the Hailuo Creek Glacier (1952--2009) were calculated using the HBV Light model. Results showed the average annual runoff in the Hailuo Creek Basin was 2,114 mm from 1952 to 2009, of which glacial melting accounted for about 1,078 mm. The river runoff in the Hailuo Creek catchment increased as a result of increased glacier runoff. Glacier runoff accounted for 51.1% of the Hailuo Creek stream flow in 1994 and increased to 72.6% in 2006. About 95% of the increased stream flow derived from the increased ~lacier runoff. 展开更多
关键词 HBV light model runoff depth glacier runoff Hailuo Creek Basin glacier mass balance
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Multi-aperture optical imaging systems and their mathematical light field acquisition models
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作者 Qiming QI Ruigang FU +2 位作者 Zhengzheng SHAO Ping WANG Hongqi FAN 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2022年第6期823-844,共22页
Inspired by the compound eyes of insects,many multi-aperture optical imaging systems have been proposed to improve the imaging quality,e.g.,to yield a high-resolution image or an image with a large field-ofview.Previo... Inspired by the compound eyes of insects,many multi-aperture optical imaging systems have been proposed to improve the imaging quality,e.g.,to yield a high-resolution image or an image with a large field-ofview.Previous research has reviewed existing multi-aperture optical imaging systems,but few papers emphasize the light field acquisition model which is essential to bridge the gap between configuration design and application.In this paper,we review typical multi-aperture optical imaging systems(i.e.,artificial compound eye,light field camera,and camera array),and then summarize general mathematical light field acquisition models for different configurations.These mathematical models provide methods for calculating the key indexes of a specific multiaperture optical imaging system,such as the field-of-view and sub-image overlap ratio.The mathematical tools simplify the quantitative design and evaluation of imaging systems for researchers. 展开更多
关键词 Multi-aperture optical imaging system Artificial compound eye light field camera Camera array light field acquisition model
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中国耕地中低产田空间分布格局及产能提升潜力(英文) 被引量:6
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作者 闫慧敏 冀咏赞 +3 位作者 刘纪远 刘芳 胡云锋 匡文慧 《Journal of Geographical Sciences》 SCIE CSCD 2016年第3期259-271,共13页
With a continuously increasing population and better food consumption levels, im- proving the efficiency of arable land use and increasing its productivity have become funda- mental strategies to meet the growing food... With a continuously increasing population and better food consumption levels, im- proving the efficiency of arable land use and increasing its productivity have become funda- mental strategies to meet the growing food security needs in China. A spatial distribution map of medium- and low-yield cropland is necessary to implement plans for cropland improvement In this study, we developed a new method to identify high-, medium-, and low-yield cropland from Moderate Resolution Imaging Spectroradiometer (MODIS) data at a spatial resolution of 500 m. The method could be used to reflect the regional heterogeneity of cropland productiv- ity because the classification standard was based on the regionalization of cropping systems in China. The results showed that the proportion of high-, medium-, and low-yield cropland in China was 21%, 39%, and 40%, respectively. About 75% of the low-yield cropland was lo- cated in hilly and mountainous areas, and about 53% of the high-yield cropland was located in plain areas. The five provinces with the largest area of high-yield cropland were all located in the Huang-Huai-Hai region, and the area amounted to 42% of the national high-yield cropland area. Meanwhile, the proportion of high-yield cropland was lower than 15% in Hei- Iongjiang, Sichuan, and Inner Mongolia, which had the largest area allocated to cropland in China. If all the medium-yield cropland could be improved to the productive level of high-yield cropland and the low-yield cropland could be improved to the level of medium-yield cropland, the total productivity of the land would increase 19% and 24%, respectively. 展开更多
关键词 food security light use efficiency model cropland productivity high- medium- and low-yield crop-land potential productivity
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Non-Destructive Crack Detection of Preserved Eggs Using a Machine Vision and Multivariate Analysis 被引量:3
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作者 WANG Fang ZHANG Shu TAN Zuojun 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第3期257-262,共6页
Pidan or century egg, also known as preserved egg, is one of the most traditional and popular egg products in China. The crack detection of preserved eggshell is very important to guarantee its quality. In this study,... Pidan or century egg, also known as preserved egg, is one of the most traditional and popular egg products in China. The crack detection of preserved eggshell is very important to guarantee its quality. In this study, we develop an image algorithm for preserved eggshell's crack detection by using natural light and polarized image. Four features including crack length, crack state coefficient, maximum projection and angular point are extracted from the natural light image by morphology calculus algorithms. The support vector machines(SVM) model with radial basis kernel function is established using the four features with an accuracy of about 92%. The detection accuracy is improved to 94% by using a new characteristic parameter of crack length on polarization image. The Multi-information fusion analysis indicates the potential for cracks detection by a real-time synthesis imaging system. 展开更多
关键词 preserved egg crack morphology calculus algorithms polarized light support vector machines(SVM) model
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Theoretical calculation of kerma coeffcients for n+^(16)O reaction below 30 MeV
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作者 渠文静 柳继锋 孙小军 《Chinese Physics C》 SCIE CAS CSCD 2009年第1期31-35,共5页
On the basis of the light nuclear reaction model, a new kerma coefficient formula has been developed. In terms of the analysis for n+^16O reactions below 30 MeV, the average energies of all kinds of the emitted parti... On the basis of the light nuclear reaction model, a new kerma coefficient formula has been developed. In terms of the analysis for n+^16O reactions below 30 MeV, the average energies of all kinds of the emitted particles are presented. The calculated partial kerma coefficients agree well with the existing experimental data. The discrepancies of the total kerma coefficients between the calculation and the measurement are analyzed in detail. 展开更多
关键词 kerma coefficient light nucleus reaction model energy balance
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