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61.
62.
高光谱成像技术因具有图谱合一的特点在作物品种鉴别方面具有较大潜力,但目前研究大多只提取利用了光谱信息,对图像信息没有进行有效利用。本文利用近红外高光谱成像仪采集了强筋、中筋、弱筋3个类型共计6个品种的单粒小麦种子高光谱图像,提取了长、宽、矩形度、圆形度、离心率等12个形态特征,并对图像中的胚乳和胚区域进行分割建立掩膜,提取了胚乳和胚区域的平均光谱信息。采用PLSDA和LSSVM方法建立基于图像信息的判别模型,结果表明强筋、弱筋两者二分类的识别率能达到98%以上,强筋、中筋两者二分类的识别率只能达到74.22%,说明近红外高光谱图像的形态信息能够反映品种间差异,但单独利用图像信息进行分类时准确度可能欠佳。采用SIMCA,PLSDA和LSSVM方法建立了胚乳和胚区域光谱信息的多分类模型,胚乳区域的分类效果较胚区域略好,说明籽粒不同部位的形状差异会影响分类效果。进一步融合光谱信息和图像信息,采用SIMCA,PLSDA和LSSVM方法建立融合模型,识别率较单独的图像或光谱信息模型均略有提升,PLSDA方法从原来的96.67%提升到98.89%, 表明充分挖掘高光谱图像所包含的形态特征和光谱特征可有效提高分类效果。 相似文献
63.
64.
在文献[1]关于电子 离子束缚态的基本概念的基础上, 对电子-离子束缚态三体系统给出严格的薛定谔方程, 给出能量的近似解:(1)对pep束缚态, 释放单能Ep≈12.5keV的X射线; (2)对D+eD+束缚态, 释放单能ED≈25keV的X射线, 同时引发少量的核聚变, 放出γ、质子、中子、氚、3He和4He。这是两个独立发生的过程。以Ni-H和氘气辉光放 电实验为例,用束缚态模型给出定量的解释。进而提出太阳耀斑发生过程中也包含电子-离子束缚态放射12.5keV和25keV两种X射线并引发少量核聚变的过程, 给出了观测结果验证。 相似文献
65.
Fusion-evaporation cross-sections for the α-induced reactions upon197Au,193Ir,191Ir,185Re,181Ta,121Sb and69Ga nuclei at bombarding energies near the Coulomb barrier have been measured by off-line observation of the γ-rays emitted
in the radioactive decay of the residual nuclei using stacked foil technique. The total fusion cross-section for the systems
have been compared with simple statistical model calculations using the code ALICE/91 as well as with the coupled channel
calculations that include the β2 and ν4 slatic deformations and dynamic couplings of the vibrational/rotational states of the target and the projet tile using the
code CCDEF. 相似文献
66.
Technique and instrumentation to detect reliably, multiplicity of neutrons emitted in sharp bursts (≤100 μs) has been developed
where a burst of as low as 15 neutrons and continuous emission of ⋍10−1 neutron/s may be detected. Using this technique, attempts were made to detect neutron emission from various experiments in
which anomalous nuclear effects (or what is commonly referred to as cold fusion) may be expected to occur. No neutrons, above
our detection threshold, were detected in the recent series of experiments. 相似文献
67.
Regression relations between the first main component, slope of the SBC curve towards the wavelength axis, and the degree
of mineralization of peat soils are established from experimental data. Errors in determination of peat soil productivity
are estimated using different spectral indices. For practical use it is recommended to measure the spectral brightness coefficients
of peat soils in the 0.50–0.75 μm range.
B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 1, pp. 102–106, January–February, 1998. 相似文献
68.
Tan Jichun Wei Xiaofeng Cheng Zhe Yuan Xiaodong Liu Lirong Shi ZHiquan 《Chinese Journal of Lasers》1998,7(1):46-50
GeometricArangementwithMultiplicityofLaserBeamsinTargetAreaTANJichunWEIXiaofeng1)CHENGZheYUANXiaodong1)LIULirongSHIZhiquan(De... 相似文献
69.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
70.
We present new theoretical calculations of nuclear fusion rates λ
f
J
from the resonant states of the muonic molecular ion 3Hedμ
++ with total angular momenta J=0,1. As a byproduct, new very accurate variational wave functions for these states have been obtained. Using these wave functions,
the probability density |Ψ(R=0)|2 in a fusion region has been calculated by extrapolating the variational solution to small internuclear distances by means
of the multi-channel adiabatic solution. Calculated fusion rates for the states J=0 and J=1 are: λ
f
0
=1.9·105s-1 and λ
f
1
=0.65·103s-1, respectively.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献