Experiments on NO2 reveal a substructure underlying the optically excited isolated hyperfine structure (hfs) levels of the molecule. This substructure is seen in a change of the symmetry of the excited molecule and is...Experiments on NO2 reveal a substructure underlying the optically excited isolated hyperfine structure (hfs) levels of the molecule. This substructure is seen in a change of the symmetry of the excited molecule and is represented by the two “states” and of a hfs-level. Optical excitation induces a transition from the ground state of the molecule to the excited state . However, the molecule evolves from to in a time τ0 ≈ 3 μs. Both and have the radiative lifetime τR ≈ 40 μs, but and differ in the degree of polarization of the fluorescence light. Zeeman coherence in the magnetic sublevels is conserved in the transition →, and optical coherence of and is able to affect (inversion effect) the transition →. This substructure, which is not caused by collisions with baryonic matter or by intramolecular dynamics in the molecule, contradicts our knowledge on an isolated hfs-level. We describe the experimental results using the assumption of extra dimensions with a compactification space of the size of the molecule, in which dark matter affects the nuclei by gravity. In , all nuclei of NO2 are confined in a single compactification space, and in , the two O nuclei of NO2 are in two different compactification spaces. Whereas and represent stable configurations of the nuclei,represents an unstable configuration because the vibrational motion in shifts one of the two O nuclei periodically off the common compactification space, enabling dark matter interaction to stimulate the transition →with the rate (τ0)−1. We revisit experimental results, which were not understood before, and we give a consistent description of these results based on the above assumption.展开更多
Accidents such as support failure and excessive deformation of roadways due to drastic changes in strata behaviors are frequently reported when mining the extra-thick coal seams Nos.3e5 in Datong coal mine with top-co...Accidents such as support failure and excessive deformation of roadways due to drastic changes in strata behaviors are frequently reported when mining the extra-thick coal seams Nos.3e5 in Datong coal mine with top-coal caving method,which significantly hampers the mine's normal production.To understand the mechanism of strata failure,this paper presented a structure evolution model with respect to strata behaviors.Then the behaviors of strata overlying the extra-thick coal seams were studied with the combined method of theoretical analysis,physical simulation,and field measurement.The results show that the key strata,which are usually thick-hard strata,play an important role in overlying movement and may influence the mining-induced strata behaviors in the working face using top-coal caving method.The structural model of far-field key strata presents a 'masonry beam' type structure when'horizontal O-X' breakage type happens.The rotational motion of the block imposed radial compressive stress on the surrounding rock mass of the roadway.This can induce excessive deformation of roadway near the goaf.Besides,this paper proposed a pre-control technology for the hard roof based on fracture holes and underground roof pre-splitting.It could effectively reduce stress concentration and release the accumulated energy of the strata,when mining underground coal resources with top-coal caving method.展开更多
超大规模多输入多输出(Extra-Large Scale Multiple-Input Multiple-Output,XL-MIMO)是未来的第六代移动通信(The 6th Generation Mobile Communication Technology,6G)关键技术之一,但是由于XL-MIMO系统采用了超大规模天线阵列,其信号...超大规模多输入多输出(Extra-Large Scale Multiple-Input Multiple-Output,XL-MIMO)是未来的第六代移动通信(The 6th Generation Mobile Communication Technology,6G)关键技术之一,但是由于XL-MIMO系统采用了超大规模天线阵列,其信号处理需求非常庞大,增加了计算复杂度。这对信号的检测算法有了更高的要求,由此对XL-MIMO系统中低复杂度算法进行研究是十分重要的。首先介绍了XL-MIMO系统信道模型,然后引入了预编码技术,将随机Kaczmarz算法和传统的MMSE算法在完美非平稳信道的归一化传输功率的误码率情况、用户数量复杂度情况、天线数量复杂度情况进行了仿真分析与比较。结果表明随机Kaczmarz算法具有更低的计算复杂度,并且是一种可以准确实现的快速算法。展开更多
文摘Experiments on NO2 reveal a substructure underlying the optically excited isolated hyperfine structure (hfs) levels of the molecule. This substructure is seen in a change of the symmetry of the excited molecule and is represented by the two “states” and of a hfs-level. Optical excitation induces a transition from the ground state of the molecule to the excited state . However, the molecule evolves from to in a time τ0 ≈ 3 μs. Both and have the radiative lifetime τR ≈ 40 μs, but and differ in the degree of polarization of the fluorescence light. Zeeman coherence in the magnetic sublevels is conserved in the transition →, and optical coherence of and is able to affect (inversion effect) the transition →. This substructure, which is not caused by collisions with baryonic matter or by intramolecular dynamics in the molecule, contradicts our knowledge on an isolated hfs-level. We describe the experimental results using the assumption of extra dimensions with a compactification space of the size of the molecule, in which dark matter affects the nuclei by gravity. In , all nuclei of NO2 are confined in a single compactification space, and in , the two O nuclei of NO2 are in two different compactification spaces. Whereas and represent stable configurations of the nuclei,represents an unstable configuration because the vibrational motion in shifts one of the two O nuclei periodically off the common compactification space, enabling dark matter interaction to stimulate the transition →with the rate (τ0)−1. We revisit experimental results, which were not understood before, and we give a consistent description of these results based on the above assumption.
基金supported by the Special Funding Projects of“Sanjin Scholars”Supporting Plan(Grant No.2050205)
文摘Accidents such as support failure and excessive deformation of roadways due to drastic changes in strata behaviors are frequently reported when mining the extra-thick coal seams Nos.3e5 in Datong coal mine with top-coal caving method,which significantly hampers the mine's normal production.To understand the mechanism of strata failure,this paper presented a structure evolution model with respect to strata behaviors.Then the behaviors of strata overlying the extra-thick coal seams were studied with the combined method of theoretical analysis,physical simulation,and field measurement.The results show that the key strata,which are usually thick-hard strata,play an important role in overlying movement and may influence the mining-induced strata behaviors in the working face using top-coal caving method.The structural model of far-field key strata presents a 'masonry beam' type structure when'horizontal O-X' breakage type happens.The rotational motion of the block imposed radial compressive stress on the surrounding rock mass of the roadway.This can induce excessive deformation of roadway near the goaf.Besides,this paper proposed a pre-control technology for the hard roof based on fracture holes and underground roof pre-splitting.It could effectively reduce stress concentration and release the accumulated energy of the strata,when mining underground coal resources with top-coal caving method.
文摘超大规模多输入多输出(Extra-Large Scale Multiple-Input Multiple-Output,XL-MIMO)是未来的第六代移动通信(The 6th Generation Mobile Communication Technology,6G)关键技术之一,但是由于XL-MIMO系统采用了超大规模天线阵列,其信号处理需求非常庞大,增加了计算复杂度。这对信号的检测算法有了更高的要求,由此对XL-MIMO系统中低复杂度算法进行研究是十分重要的。首先介绍了XL-MIMO系统信道模型,然后引入了预编码技术,将随机Kaczmarz算法和传统的MMSE算法在完美非平稳信道的归一化传输功率的误码率情况、用户数量复杂度情况、天线数量复杂度情况进行了仿真分析与比较。结果表明随机Kaczmarz算法具有更低的计算复杂度,并且是一种可以准确实现的快速算法。