A monitoring program was developed to assess the cover of saltgrass managed for dust control on the saline dry Owens Lake. Although the original intent was to manage the vegetation as total cover that included green a...A monitoring program was developed to assess the cover of saltgrass managed for dust control on the saline dry Owens Lake. Although the original intent was to manage the vegetation as total cover that included green and senesced leaf and stem material, aged leaves that make up a large proportion of total cover were not differentiable spectrally from the background salt and lakebed. Hence, greenness-based indices were explored for detection of plant recruitment. Since all plant cover begins as green and growing, greenness indices provide a measure of all future cover whether living or senesced. The criteria for judging compliance were changed so that spatially variable vegetation cover measured as a milestone will need to be met in the future. A derivative of NDVI, NDVIx, calculated using scene statistics, proved highly accurate, to about 0.001 of this index and with an average signal to noise ratio of 64. This high level of accuracy allowed detection of small changes in vegetation growth and vigor. Performance according to the benchmark-as-par standard was determined through combined use of cumulative distribution functions and derivative maps.展开更多
Extensive dust control on the dry Owens Lake mainly uses constructed basins that are flooded with shallow depths of fresh water. This dust control is mandated by law as a minimum percent of the area of each individual...Extensive dust control on the dry Owens Lake mainly uses constructed basins that are flooded with shallow depths of fresh water. This dust control is mandated by law as a minimum percent of the area of each individual wetting basin. Wetted surfaces are evaluated for area and degree of wetness using the shortwave infrared (SWIR) band of Landsat TM, or similar earth observation satellite sensor. The SWIR region appropriate for these measurements lies within the electromagnetic spectrum between about 1.5 and 1.8 μm wavelengths. A threshold value for Landsat TM5 band 5 reflectance of 0.19 was found to conform with surfaces having a threshold for adequate wetting at a nascent point where rapid drying would occur following loss of capillary connection with groundwater. This threshold is robust and requires no atmospheric correction for the effects of aerosol scatter and attenuation as long as the features on the image appear clear. Monthly monitoring of surface wetting has proven accurate, verifiable and repeatable using these methods. This threshold can be calibrated for any Earth observation satellite that records the appropriate SWIR region. The monitoring program is expected to provide major input for the final phase of the dust control program that will have a focus to conserve water and resources.展开更多
The problem of identity is a hot issue frequently talked about in many literary works.Especially,the identity problem or the search for identity can be seen as one of the major themes in the literary works written by ...The problem of identity is a hot issue frequently talked about in many literary works.Especially,the identity problem or the search for identity can be seen as one of the major themes in the literary works written by ethnic writers.Louis Owens is a distinguished American Indian writer who has Choctaw,Cherokee,and Irish descent.In his debut work Wolfsong which was published in 1995,Louis Owens depicts the story about the protagonist Tom Joseph’s search for his lost American Indian identity.With deep knowledge and notion about American Indian culture and tradition,Owens reveals his worry about their own identity and precious culture and tradition which are disappearing gradually.This paper tries to analyze Tom Joseph’s search for his identity,and discusses how the American Indian tradition and culture influence his endeavor to find the lost American Indian identity.展开更多
The Owen’s T function is presented in four new ways, one of them as a series similar to the Euler’s arctangent series divided by 2π, which is its majorant series. All possibilities enable numerically stable ...The Owen’s T function is presented in four new ways, one of them as a series similar to the Euler’s arctangent series divided by 2π, which is its majorant series. All possibilities enable numerically stable and fast convergent computation of the bivariate normal integral with simple recursion. When tested computation on a random sample of one million parameter triplets with uniformly distributed components and using double precision arithmetic, the maximum absolute error was 3.45 × 10<sup>-</sup><sup>16</sup>. In additional testing, focusing on cases with correlation coefficients close to one in absolute value, when the computation may be very sensitive to small rounding errors, the accuracy was retained. In rare potentially critical cases, a simple adjustment to the computation procedure was performed—one potentially critical computation was replaced with two equivalent non-critical ones. All new series are suitable for vector and high-precision computation, assuming they are supplemented with appropriate efficient and accurate computation of the arctangent and standard normal cumulative distribution functions. They are implemented by the R package Phi2rho, available on CRAN. Its functions allow vector arguments and are ready to work with the Rmpfr package, which enables the use of arbitrary precision instead of double precision numbers. A special test with up to 1024-bit precision computation is also presented.展开更多
针对当前用户侧分布式储能存在的成本较高、利用率低、布局分散等问题,提出一种分布式储能双层合作共享策略,通过分时复用提高储能资源的利用率和经济性。首先,阐述以社区为上层单元、以用户为下层单元的分布式储能双层点对点(peer to p...针对当前用户侧分布式储能存在的成本较高、利用率低、布局分散等问题,提出一种分布式储能双层合作共享策略,通过分时复用提高储能资源的利用率和经济性。首先,阐述以社区为上层单元、以用户为下层单元的分布式储能双层点对点(peer to peer,P2P)共享交易模式。其次,将分布式储能合作共享问题分解为容量交易子问题和成本分摊子问题。接着,采用交替方向乘子(alternating direction method of multipliers,ADMM)算法构建分布式储能容量双层交易模型,上层侧重于社区间储能共享优化,而下层旨在解决社区内用户储能共享优化。在此基础上,进一步设计一种基于改进Owen值法的双层成本分摊策略,上层采用Shapley值法进行社区间成本分摊,而在下层通过双边Shapley值法完成社区内成本再分摊,以此解决广泛用户群体带来的维数灾和隐私保护问题,同时兼顾各方收益均衡。最后,通过算例仿真验证所提P2P合作共享模式的可行性和优越性,以及成本分摊策略的公平性。展开更多
In our previous studies, we identified 3 Trichoderma strains with anti-Fusarium oxysporum activity, including T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886. Here, we evaluated the effects of these 3 T...In our previous studies, we identified 3 Trichoderma strains with anti-Fusarium oxysporum activity, including T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886. Here, we evaluated the effects of these 3 Trichoderma strains on preventing cucumber fusarium wilt through pot culture and greenhouse culture experiments. All 3 Trichoderma strains demonstrated higher control effects toward cucumber fusarium wilt than previous studies, with efficacies over 78%. Additionally, inoculation with the 3 Trichoderma strains significantly promoted the quality and yield of cucumbers. Among the 3 strains, Trichoderma 866 was the most effective, with disease control efficacy of 78.64% and a cucumber yield increase of 33%. Furthermore, seedlings inoculated with Trichoderma exhibited significantly increased measures of plant height, stem diameter, leaf area, aboveground fresh weight, underground fresh weight, chlorophyll content, and nitric nitrogen content, as well as the activities of several stress-resistance enzymes, including superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), polyphenol oxidase(PPO), and ascorbate oxidase(AAO). In addition, the plants inoculated with Trichoderma showed decreased cell membrane permeability and malondialdehyde(MDA) content in the leaves. Together, our results suggest that T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886 inoculations inhibit F. oxysporum infection, stimulate the metabolism in cucumbers, and enhance the activities of stress-resistance enzymes, which consequently promote the growth of cucumber plants, prevent cucumber fusarium wilt, and improve the yield and quality of cucumbers. T. harzianum is a commonly used biocontrol fungus, while few studies have focused on T. asperellum or T. koningense. In this study, strains of T. asperellum and T. pseudokoningii showed excellent plant disease prevention and growth promoting effects on cucumber, indicating that they also have great potential as biocontrol fungi.展开更多
文摘A monitoring program was developed to assess the cover of saltgrass managed for dust control on the saline dry Owens Lake. Although the original intent was to manage the vegetation as total cover that included green and senesced leaf and stem material, aged leaves that make up a large proportion of total cover were not differentiable spectrally from the background salt and lakebed. Hence, greenness-based indices were explored for detection of plant recruitment. Since all plant cover begins as green and growing, greenness indices provide a measure of all future cover whether living or senesced. The criteria for judging compliance were changed so that spatially variable vegetation cover measured as a milestone will need to be met in the future. A derivative of NDVI, NDVIx, calculated using scene statistics, proved highly accurate, to about 0.001 of this index and with an average signal to noise ratio of 64. This high level of accuracy allowed detection of small changes in vegetation growth and vigor. Performance according to the benchmark-as-par standard was determined through combined use of cumulative distribution functions and derivative maps.
文摘Extensive dust control on the dry Owens Lake mainly uses constructed basins that are flooded with shallow depths of fresh water. This dust control is mandated by law as a minimum percent of the area of each individual wetting basin. Wetted surfaces are evaluated for area and degree of wetness using the shortwave infrared (SWIR) band of Landsat TM, or similar earth observation satellite sensor. The SWIR region appropriate for these measurements lies within the electromagnetic spectrum between about 1.5 and 1.8 μm wavelengths. A threshold value for Landsat TM5 band 5 reflectance of 0.19 was found to conform with surfaces having a threshold for adequate wetting at a nascent point where rapid drying would occur following loss of capillary connection with groundwater. This threshold is robust and requires no atmospheric correction for the effects of aerosol scatter and attenuation as long as the features on the image appear clear. Monthly monitoring of surface wetting has proven accurate, verifiable and repeatable using these methods. This threshold can be calibrated for any Earth observation satellite that records the appropriate SWIR region. The monitoring program is expected to provide major input for the final phase of the dust control program that will have a focus to conserve water and resources.
文摘The problem of identity is a hot issue frequently talked about in many literary works.Especially,the identity problem or the search for identity can be seen as one of the major themes in the literary works written by ethnic writers.Louis Owens is a distinguished American Indian writer who has Choctaw,Cherokee,and Irish descent.In his debut work Wolfsong which was published in 1995,Louis Owens depicts the story about the protagonist Tom Joseph’s search for his lost American Indian identity.With deep knowledge and notion about American Indian culture and tradition,Owens reveals his worry about their own identity and precious culture and tradition which are disappearing gradually.This paper tries to analyze Tom Joseph’s search for his identity,and discusses how the American Indian tradition and culture influence his endeavor to find the lost American Indian identity.
文摘The Owen’s T function is presented in four new ways, one of them as a series similar to the Euler’s arctangent series divided by 2π, which is its majorant series. All possibilities enable numerically stable and fast convergent computation of the bivariate normal integral with simple recursion. When tested computation on a random sample of one million parameter triplets with uniformly distributed components and using double precision arithmetic, the maximum absolute error was 3.45 × 10<sup>-</sup><sup>16</sup>. In additional testing, focusing on cases with correlation coefficients close to one in absolute value, when the computation may be very sensitive to small rounding errors, the accuracy was retained. In rare potentially critical cases, a simple adjustment to the computation procedure was performed—one potentially critical computation was replaced with two equivalent non-critical ones. All new series are suitable for vector and high-precision computation, assuming they are supplemented with appropriate efficient and accurate computation of the arctangent and standard normal cumulative distribution functions. They are implemented by the R package Phi2rho, available on CRAN. Its functions allow vector arguments and are ready to work with the Rmpfr package, which enables the use of arbitrary precision instead of double precision numbers. A special test with up to 1024-bit precision computation is also presented.
文摘针对当前用户侧分布式储能存在的成本较高、利用率低、布局分散等问题,提出一种分布式储能双层合作共享策略,通过分时复用提高储能资源的利用率和经济性。首先,阐述以社区为上层单元、以用户为下层单元的分布式储能双层点对点(peer to peer,P2P)共享交易模式。其次,将分布式储能合作共享问题分解为容量交易子问题和成本分摊子问题。接着,采用交替方向乘子(alternating direction method of multipliers,ADMM)算法构建分布式储能容量双层交易模型,上层侧重于社区间储能共享优化,而下层旨在解决社区内用户储能共享优化。在此基础上,进一步设计一种基于改进Owen值法的双层成本分摊策略,上层采用Shapley值法进行社区间成本分摊,而在下层通过双边Shapley值法完成社区内成本再分摊,以此解决广泛用户群体带来的维数灾和隐私保护问题,同时兼顾各方收益均衡。最后,通过算例仿真验证所提P2P合作共享模式的可行性和优越性,以及成本分摊策略的公平性。
基金support from the National Key R&D Program of China (2018YFD0201202)the National Science and Technology Basic Work, China (2014FY120900)the 948 Program of China (2011-G4)
文摘In our previous studies, we identified 3 Trichoderma strains with anti-Fusarium oxysporum activity, including T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886. Here, we evaluated the effects of these 3 Trichoderma strains on preventing cucumber fusarium wilt through pot culture and greenhouse culture experiments. All 3 Trichoderma strains demonstrated higher control effects toward cucumber fusarium wilt than previous studies, with efficacies over 78%. Additionally, inoculation with the 3 Trichoderma strains significantly promoted the quality and yield of cucumbers. Among the 3 strains, Trichoderma 866 was the most effective, with disease control efficacy of 78.64% and a cucumber yield increase of 33%. Furthermore, seedlings inoculated with Trichoderma exhibited significantly increased measures of plant height, stem diameter, leaf area, aboveground fresh weight, underground fresh weight, chlorophyll content, and nitric nitrogen content, as well as the activities of several stress-resistance enzymes, including superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), polyphenol oxidase(PPO), and ascorbate oxidase(AAO). In addition, the plants inoculated with Trichoderma showed decreased cell membrane permeability and malondialdehyde(MDA) content in the leaves. Together, our results suggest that T. asperellum 525, T. harzianum 610, and T. pseudokoningii 886 inoculations inhibit F. oxysporum infection, stimulate the metabolism in cucumbers, and enhance the activities of stress-resistance enzymes, which consequently promote the growth of cucumber plants, prevent cucumber fusarium wilt, and improve the yield and quality of cucumbers. T. harzianum is a commonly used biocontrol fungus, while few studies have focused on T. asperellum or T. koningense. In this study, strains of T. asperellum and T. pseudokoningii showed excellent plant disease prevention and growth promoting effects on cucumber, indicating that they also have great potential as biocontrol fungi.
