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971.
无线携能通信(Simultaneous Wireless Information and Power Transfer,SWIPT)技术提高了频谱的利用率,同时可实现传统网络的节能减排,为网络提供了更智能的自治能力、更广泛的覆盖范围、更高度集成的系统能力等美好前景.针对这一新的研究领域,本文从资源优化分配和安全传输的角...  相似文献   
972.
在质量加权坐标系下用离散变量表示(DVR)方案研究了H2O基电子态2种特殊振动模式的振动光谱.计算中应用多项式函数拟合从头算结果得到的内坐标系下的基态解析势能面,经坐标变换得到质量加权坐标系下的相应势能面.分子的哈密顿形式在质量加权坐标下给出.用H2O振动能级的计算验证算法的可行性,从而为二维多光子电离光电子能谱的模拟奠定理论基础.  相似文献   
973.
Structural features of various molecular systems with symmetry of point groups ranging fromC 1 to the icosahedral symmetry are analyzed in the framework of the model suggested previously for the evaluation of order and disorder in the arrangement of atoms in a molecule based on the equationQ = I -P/3n (whereQ is the index of order, andP is the number of independent coordinates needed to fix ann-atomic molecule in the Cartesian coordinate system). TheQ value depends on various structural parameters of the molecule: the number of atoms in it, the symmetry, the dimensionality, and the number of structural degrees of freedom. The disorder indexP/3n = 1 -Q correlates with Shannon's entropy of information, andQ correlates with negentropy or excess information; this makes it possible to useP/3n as a new geometrical information molecular index that is obtained by a nonprobabilistic method. Analysis of the relationship between order and chaos in molecular systems, as well as of the specific order indexq =Q/n, makes it possible to identify both general and specific features of molecules.Translated from Izvestiya Akadernii Nauk. Seriya Khimicheskaya, No. 8, pp. 191219-121927, August, 1996.  相似文献   
974.
975.
Raman-based technologies have proved to be excellent tools for on-site and in-vivo analysis, due to the non-invasive nature of their detection, their capability of providing structure information, their high tolerance to aqueous samples, the ultra-sensitivity of surface-enhanced Raman scattering (SERS) and resonance Raman scattering (RRS), the high spatial resolution of tip-enhanced Raman scattering (TERS), and the ultrashort spectra-acquisition time for coherent anti-Stokes Raman scattering (CARS) and stimulated Raman scattering (SRS).In this review, we highlight the recent success of Raman-based technologies in various applications, including:
  • (1) 
    on-site surface analysis and chemical-reaction monitoring;
  • (2) 
    on-site identification of cultural objects, archeological studies and planetary science;
  • (3) 
    in-vivo analysis of cells and microorganisms;
  • (4) 
    in-vivo diagnosis inside human and animal bodies;
  • (5) 
    in-vivo fast Raman imaging and mapping;
  • (6) 
    the study of SERS processes; and,
  • (7) 
    assessment of nanomaterial safety.
  相似文献   
976.
Four commercially available formulations containing iron, zinc, and manganese were subjected to dissolution profile testing during 60 min and the dissolution was analyzed by ion chromatography. The obtained curves were analyzed directly by principal component analysis (PCA). The main trend (87.1% of variance) was connected with average dissolution percentage over the investigated time. The second component (11.2% of variance) is connected with shape of dissolution profile. All metals behave in the similar way and the differences were connected with excipients. An additional fit was completed on 12 kinetic models: first order kinetics (4 variants), Higuchi (2 variants), Hixson-Crowell (2 variants), Korsemeyer-Peppas, Logistic (2 variants), Peppas-Sahlin, Quadratic (2 variants), Weibull (3 variants), and Zero order kinetics (2 variants). The ranking of the fitting was performed by Akaike information criteria (AIC) values with additional PCA analysis on them, an approach presented in literature for the first time. The main trend (67.4% of variance) was connected with average fit. The second (14.8% of variance) is connected with differences of fitting ability to investigated dissolution curves. This methodology brought an overall look to trends and variances inside obtained data, both the profile shape and fitting ability to particular models.  相似文献   
977.
对"联邦滤波器信息分配系数的优选算法"一文的商榷   总被引:6,自引:0,他引:6  
介绍了联邦滤波算法和信息分配原理,指出《中国惯性技术学报》第11卷第6期“联邦滤波器信息分配系数的优选算法”一中存在一些问题,说明使用该优选算法进行信息分配,可能使主滤波器方差阵失去正定性;将联邦滤波用于GPS姿态测量,实验表明动态选择信息分配因子,相对于固定信息分配因子的算法并没有明显优势。  相似文献   
978.
信息技术与物理教学有机整合的实践探索   总被引:2,自引:0,他引:2  
从信息技术教育的目标和MCAI(多媒体计算机辅助教学)应用于物理教学的实践出发,剖析了信息技术是改革传统教学观念、实现教与学方式转变的行之有效的方法、途径和手段,为学生的主体学习、协作学习、创造性发挥提供了强有力的技术支持,使物理教学朝着自主、有特色的方向发展。实践性地探究了信息技术与物理学科教学合理、有机整合的策略。  相似文献   
979.
After being introduced by Shannon as a measure of disorder and unavailable information, the notion of entropy has found its applications in a broad range of scientific disciplines. In this paper, we present a systematic review on the applications of entropy and related information-theoretical concepts in the design, implementation and evaluation of cryptographic schemes, algorithms, devices and systems. Moreover, we study existing trends, and establish a roadmap for future research in these areas.  相似文献   
980.
In this paper, we deal with the critical problems in residue arithmetic. The reverse conversion from a Residue Number System (RNS) to positional notation is a main non-modular operation, and it constitutes a basis of other non-modular procedures used to implement various computational algorithms. We present a novel approach to the parallel reverse conversion from the residue code into a weighted number representation in the Mixed-Radix System (MRS). In our proposed method, the calculation of mixed-radix digits reduces to a parallel summation of the small word-length residues in the independent modular channels corresponding to the primary RNS moduli. The computational complexity of the developed method concerning both required modular addition operations and one-input lookup tables is estimated as Ok2/2, where k equals the number of used moduli. The time complexity is Olog2k modular clock cycles. In pipeline mode, the throughput rate of the proposed algorithm is one reverse conversion in one modular clock cycle.  相似文献   
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