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Boundedness and convergence of perturbed corrections for helium-like ions in ground states
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Applying the improved Rayleigh SchrSdinger perturbation theory based on an integral equation to helium-like ions in ground states and treating electron correlations as perturbations, we obtain the second-order corrections to wavefunctions consisting of a few terms and the third-order corrections to energicity. It is demonstrated that the corrected wavefunctions are bounded and quadratically integrable, and the corresponding perturbation series is convergent. The results clear off the previous distrust for the convergence in the quantum perturbation theory and show a reciprocal development on the quantum perturbation problem of the ground state helium-like systems. 相似文献
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The performance of the so-called superconvergent quantum perturbation theory (Wenhua Hal et al2000 Phys. Rev. A 61 052105) is investigated for the case of the ground-state energy of the helium-like ions. The scaling transformation τ → τ/Z applied to the Hamiltonian of a two-electron atomic ion with a nuclear charge Z (in atomic units). Using the improved Rayleigh-SchrSdinger perturbation theory based on the integral equation to helium-like ions in the ground states and treating the electron correlations as perturbations, we have performed a third-order perturbation calculation and obtained the second-order corrected wavefunctions consisting of a few terms and third-order energy corrections. We find that third-order and higher-order energy corrections are improved with decreasing nuclear charge. This result means that the former is quadratically integrable and the latter is physically meaningful. The improved quantum perturbation theory fits the higher-order perturbation case. This work shows that it is a development on the quantum perturbation problem of helium-like systems. 相似文献
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应急广播是政府及相关部门向公众提供紧急信息的一种手段,是国家应急体系和国家公共服务体系的重要组成部分。我国的应急广播系统除了发布预警信息之外,还承担着政策宣传和舆论引导的职责,尤其是在边疆少数民族地区,承担了维护社会稳定的重要职能。因此,应急广播系统的传输安全、信息完整性的保护尤为重要。针对广播系统的业务特点以及广播领域常见的攻击破坏方式,提出了一种适用于各类应急广播传输通道的保护方式,可以有效抵御重放攻击方式。 相似文献
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调频广播以其技术的成熟性和部署实施的方便性广泛应用于我国新农村“村村响”系统中。调频广播传输带宽窄,传输数据效率低,针对应急广播信息安全保护标准中要求的数据保护,要采用基于SM2算法的数字签名方式,存在一定的传输问题。根据标准要求,此方式下要传输的附加保护信息最少要74 Byte,其中数字签名有64 Byte,调频广播终端接收此数据需要2~5 s,且在接收过程中极易因干扰出错,因此需要重复传输,严重影响应急广播消息的播发效率。因此,提出了一种基于SM2算法适用于调频广播这类窄带传输的信息保护签名算法,在保障一定安全强度的前提下,减少了要传输的附加保护信息长度,提升了应急广播指令的传输效率。 相似文献
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以噻二唑-2-氨甲基酚(1)为原料, 与异硫氰酸苯酯反应, 以中等到良好的产率得到噻二唑基N-苯基取代硫脲类化合物(3a~3i); 而化合物1与活性较高的N,N-二甲胺基硫代甲酰氯反应, 则可以得到—NH和—OH同时反应的含有N,N-二甲基硫脲和N,N-二甲基硫代氨基甲酸芳酯官能团的产物. 利用核磁共振、 红外光谱以及高分辨质谱等手段对产物结构进行了表征. 相似文献
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对矿区人员入矿、出矿及重要生产活动行为进行精准定位与准确识别是实现矿区智能安全生产的重要基础.针对复杂的矿区生产环境,提出一种基于MK-YOLOV4的矿区人员无标注视频检索方法,实现对矿区重要关口监控无标注视频的多人员目标检测和各人员身份重识别.首先,提出MK-YOLOV4算法,实现无标注视频多人员检测,在YOLOV4... 相似文献