Storage and transportation of vegetable commercial seedlings becomes an important link along with the continuous expansion of planting areas of facility vegetables and vegetable seedling culture industry. In this stud...Storage and transportation of vegetable commercial seedlings becomes an important link along with the continuous expansion of planting areas of facility vegetables and vegetable seedling culture industry. In this study,pepper variety‘Nongda 24' was as the experimental material,and changes in the morphological and physiological indicators of plug seedlings in different low temperature( 6 and 11℃) and poor light environments were studied to find suitable storage environmental conditions. The results showed that pepper seedlings could be stored and transported for 14 days when storage temperature was 11℃ and light conditions such as light intensity and photoperiod were 30 μmol/( m^2·s)and 12 h/d by using a fluorescent lamp with R∶ B ratio of 1. 9,and 15 μmol/( m^2·s) and 24 h/d by using LED with R∶ B ratio of 1. 3,respectively. Moreover,the quality of pepper seedlings could be protected effectively. Compared to the fluorescent lamp,LED with high luminous efficiency and low energy consumption was suitable for the storage or long-distance transportation of pepper seedlings in low temperature and poor light environments.展开更多
An alternative way to perform fractional Fourier transform is proposed. The system is illuminated by a divergent beam. It has one more degree of freedom in arrangement than the previous system. Mathematically, the cho...An alternative way to perform fractional Fourier transform is proposed. The system is illuminated by a divergent beam. It has one more degree of freedom in arrangement than the previous system. Mathematically, the choice of focal length of one of the two lenses depends on an easily adjustable parameter which determines the location of illuminating point source.展开更多
Photosynthetic products are mainly produced by leaf and green silique of oil-seed rape （Brassica napus L.） at reproductive growth stage. This study aimed to compare photosynthetic features of leaf and green silique ...Photosynthetic products are mainly produced by leaf and green silique of oil-seed rape （Brassica napus L.） at reproductive growth stage. This study aimed to compare photosynthetic features of leaf and green silique of ‘Qinyou 7’ hybrid oilseed rape variety. Results showed that, during photosynthetic day time, net photosynthetic rate （PN） and sto-matal conductance （gs） of leaf were markedly higher than that of silique. Compared with silique, leaf had signifcant higher PN, gs, light saturated net photosynthetic rate （PNmax）, light saturation point （LSP）, and apparent quantum yield （AQY）, but lower light compensa-tion point （LCP）, CO2 compensation point （Γ） and carboxylation effciency （CE） under var-ious light densities and CO2 concentrations. Carboxylation activities of ribulose-1, 5-bis-phosphate carboxylase/oxygenase （Rubisco）, phosphoenolpyruvate carboxylase （PEPC） and chlorophyll a, b （Chl a, b） of leaf were signifcantly higher than that of silique shell. Our study demonstrated that leaf of oilseed rape at reproductive growth stage had higher photosynthetic capacity than green silique due to its higher carboxylation activity of pho-tosynthetic enzymes as well as higher gs and Chl contents. This study might have good implication in selecting a biological control strategy to enhance seed yield and oil produc-tion of oilseed rape.展开更多
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
Aims Screening tree species in tropical rainforest according to their shade tolerance is important to efficiently manage the native trees of economic significance in secondary forest enrichment regimes.The objective o...Aims Screening tree species in tropical rainforest according to their shade tolerance is important to efficiently manage the native trees of economic significance in secondary forest enrichment regimes.The objective of this study was to determine the whole-plant light compensation point(WPLCP)and compare the phenotypic plasticity in relation to growth and carbon allocation of Cariniana legalis and Gallesia integrifolia seedlings under low light availability.Methods Seedlings were cultivated for 77 days under conditions of five photosynthetically active radiation(PAR)(0.02,1.1,2.3,4.5 and 5.9 mol photons m^(−2)day^(−1))in three replicates.Growth and carbon allocation variables were determined.Important Findings Growth rates of C.legalis were higher and lower than those of G.integrifolia under 1.1 and 5.9 mol photons m^(−2)day^(−1),respectively.The WPLCP differed significantly between the two species.In accordance with the criteria of the shade tolerance classification for these two tropical tree species,our results showed that C.legalis had lower WPLCP and phenotypic plasticity in terms of higher growth rates and greater shade tolerance than G.integrifolia.From a practical point of view,we demonstrated that the differential linkage between growth and changing PAR between the two species can become a useful tool for comparing and selecting tree species in forest enrichment projects.展开更多
This paper proposes a modification of the filtered importance sampling method, and improves the quality of virtual spherical Gaussian light(VSGL)-based real-time glossy indirect illumination using this modification. T...This paper proposes a modification of the filtered importance sampling method, and improves the quality of virtual spherical Gaussian light(VSGL)-based real-time glossy indirect illumination using this modification. The original filtered importance sampling method produces large overlaps of and gaps between filtering kernels for high-frequency probability density functions(PDFs). This is because the size of the filtering kernel is determined using the PDF at the sampled center of the kernel. To reduce those overlaps and gaps, this paper determines the kernel size using the integral of the PDF within the filtering kernel. Our key insight is that these integrals are approximately constant, if kernel centers are sampled using stratified sampling. Therefore, an appropriate kernel size can be obtained by solving this integral equation. Using the proposed kernel size for filtered importance samplingbased VSGL generation, undesirable artifacts are significantly reduced with a negligibly small overhead.展开更多
基金Supported by National Key Research and Development Program of China(2017YFB0403901)
文摘Storage and transportation of vegetable commercial seedlings becomes an important link along with the continuous expansion of planting areas of facility vegetables and vegetable seedling culture industry. In this study,pepper variety‘Nongda 24' was as the experimental material,and changes in the morphological and physiological indicators of plug seedlings in different low temperature( 6 and 11℃) and poor light environments were studied to find suitable storage environmental conditions. The results showed that pepper seedlings could be stored and transported for 14 days when storage temperature was 11℃ and light conditions such as light intensity and photoperiod were 30 μmol/( m^2·s)and 12 h/d by using a fluorescent lamp with R∶ B ratio of 1. 9,and 15 μmol/( m^2·s) and 24 h/d by using LED with R∶ B ratio of 1. 3,respectively. Moreover,the quality of pepper seedlings could be protected effectively. Compared to the fluorescent lamp,LED with high luminous efficiency and low energy consumption was suitable for the storage or long-distance transportation of pepper seedlings in low temperature and poor light environments.
文摘An alternative way to perform fractional Fourier transform is proposed. The system is illuminated by a divergent beam. It has one more degree of freedom in arrangement than the previous system. Mathematically, the choice of focal length of one of the two lenses depends on an easily adjustable parameter which determines the location of illuminating point source.
基金supported by the Key R&D Program Project of Shaanxi Province,China(2018NY-025)the Key R&D Program Project of Shaanxi Province,China(2017ZDXM-NY-007)
文摘Photosynthetic products are mainly produced by leaf and green silique of oil-seed rape （Brassica napus L.） at reproductive growth stage. This study aimed to compare photosynthetic features of leaf and green silique of ‘Qinyou 7’ hybrid oilseed rape variety. Results showed that, during photosynthetic day time, net photosynthetic rate （PN） and sto-matal conductance （gs） of leaf were markedly higher than that of silique. Compared with silique, leaf had signifcant higher PN, gs, light saturated net photosynthetic rate （PNmax）, light saturation point （LSP）, and apparent quantum yield （AQY）, but lower light compensa-tion point （LCP）, CO2 compensation point （Γ） and carboxylation effciency （CE） under var-ious light densities and CO2 concentrations. Carboxylation activities of ribulose-1, 5-bis-phosphate carboxylase/oxygenase （Rubisco）, phosphoenolpyruvate carboxylase （PEPC） and chlorophyll a, b （Chl a, b） of leaf were signifcantly higher than that of silique shell. Our study demonstrated that leaf of oilseed rape at reproductive growth stage had higher photosynthetic capacity than green silique due to its higher carboxylation activity of pho-tosynthetic enzymes as well as higher gs and Chl contents. This study might have good implication in selecting a biological control strategy to enhance seed yield and oil produc-tion of oilseed rape.
文摘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.
基金Marcelo S.Mielke gratefully acknowledge CNPq(Brazilian National Council for Scientific and Technological Development)for the award of fellowship of scientific productivity(305477/2018-8).
文摘Aims Screening tree species in tropical rainforest according to their shade tolerance is important to efficiently manage the native trees of economic significance in secondary forest enrichment regimes.The objective of this study was to determine the whole-plant light compensation point(WPLCP)and compare the phenotypic plasticity in relation to growth and carbon allocation of Cariniana legalis and Gallesia integrifolia seedlings under low light availability.Methods Seedlings were cultivated for 77 days under conditions of five photosynthetically active radiation(PAR)(0.02,1.1,2.3,4.5 and 5.9 mol photons m^(−2)day^(−1))in three replicates.Growth and carbon allocation variables were determined.Important Findings Growth rates of C.legalis were higher and lower than those of G.integrifolia under 1.1 and 5.9 mol photons m^(−2)day^(−1),respectively.The WPLCP differed significantly between the two species.In accordance with the criteria of the shade tolerance classification for these two tropical tree species,our results showed that C.legalis had lower WPLCP and phenotypic plasticity in terms of higher growth rates and greater shade tolerance than G.integrifolia.From a practical point of view,we demonstrated that the differential linkage between growth and changing PAR between the two species can become a useful tool for comparing and selecting tree species in forest enrichment projects.
文摘This paper proposes a modification of the filtered importance sampling method, and improves the quality of virtual spherical Gaussian light(VSGL)-based real-time glossy indirect illumination using this modification. The original filtered importance sampling method produces large overlaps of and gaps between filtering kernels for high-frequency probability density functions(PDFs). This is because the size of the filtering kernel is determined using the PDF at the sampled center of the kernel. To reduce those overlaps and gaps, this paper determines the kernel size using the integral of the PDF within the filtering kernel. Our key insight is that these integrals are approximately constant, if kernel centers are sampled using stratified sampling. Therefore, an appropriate kernel size can be obtained by solving this integral equation. Using the proposed kernel size for filtered importance samplingbased VSGL generation, undesirable artifacts are significantly reduced with a negligibly small overhead.
