Luby Transform Coding Aided Iterative Detection for Downlink SDMA Systems

A Luby Transform (LT) coded downlink Spatial Division Multiple Access (SDMA) system using iterative detection is proposed, which invokes a low-complexity near-Maximum-Likelihood (ML) Sphere Decoder (SD). The Ethernet-based Internet section of the transmission chain inflicts random packet erasures, which is modelled by the Binary Erasure Channel (BEC), which the wireless downlink imposes both fading and noise. A novel log-Likelihood Ratio based packet reliability metric is used for identifying the channel-decoded packets, which are likely to be error-infested. Packets having residual errors must not be passed on to the KT decoder for the sake of avoiding LT-decoding –induced error propagation. The proposed scheme is capable of maintaining an infinitesimally low packet error ratio in the downlink of the wireless Internet for Eb/n0 values in excess of about 3dB

Adicción al teléfono móvil y ansiedad social entre adolescentes chinos: papel mediador de los problemas interpersonales

Objectives:Mobile phone addiction (MPA) has frequently report-ed to be correlated with psychological disorders such as depression, stress and anxiety among young population. However, the extent to which these factors are correlated with MPA and the potential mechanism underlying those relationships are conclusive. This study aimed to investigate the as-sociation between MPA level and social anxiety among Chinese adolescents, and examined the mediation effect of interpersonal problems between them. Methods: A sample of 1027 school-based students selected by a stratified-cluster random sampling method responded to questionnaires regarding MPA Index, Social Interaction Anxiousness Scale, Interpersonal Problems Inventory, and demographic variables. Spearman correlation and multiple linear regression analyses were performed to investigate the extent of the association between MPA and social anxiety, and Sobel test and bootstrapping sampling confirmed the mediating role ofinterpersonal problems.Results: Of all students in our study, 5.9% were MPA, and MPA score was positively correlated with social anxiety after controlled for de-mographic variables in the adjusted model. Multiple mediation regression analysis revealed that the interpersonal problem was a significant partial mediator between MPA and social anxiety. Conclusion:The MPA adolescents were a subgroup population who need to pay more attention to prevent social anxiety. Improving interpersonal problems might be aneffec-tive approach to deal with MPA-induced social anxiety in adolescents.Objetivos: Con frecuencia se ha informado que la adicción al teléfono móvil (MPA) está correlacionada con trastornos psicológicos como la depresión, el estrés y la ansiedad entre la población joven. Sin embargo, el grado en que estos factores se correlacionan con el AMP y el mecanismo potencial subyacente a esas relaciones son concluyentes. Este estudio tuvo como objetivo investigar la asociación entre el nivel de AMP y la ansiedad social entre adolescentes chinos y examinó el efecto de mediación de los problemas interpersonales entre ellos. Métodos: Una muestra de 1027 estudiantes escolares seleccionados mediante un método de muestreo aleatorio por conglomerados estratificados respondió a cuestionarios sobre el índice MPA, la escala de ansiedad por interacción social, el inventario de problemas interpersonales y variables demográficas. Se realizaron análisis de correlación de Spearman y de regresión lineal múltiple para investigar el alcance de la asociación entre la AMP y la ansiedad social, y la prueba de Sobel y el muestreo de arranque confirmaron el papel mediador de los problemas interpersonales. Resultados: De todos los estudiantes de nuestro estudio, el 5,9% tenían AMP, y la puntuación de AMP se correlacionó positivamente con la ansiedad social después de controlar las variables demográficas en el modelo ajustado. El análisis de regresión de mediación múltiple reveló que el problema interpersonal era un mediador parcial significativo entre la AMP y la ansiedad social. Conclusión: Los adolescentes del AMP fueron un subgrupo de población que necesita prestar más atención para prevenir la ansiedad social. Mejorar los problemas interpersonales podría ser un enfoque eficaz para abordar la ansiedad social inducida por el AMP en los adolescentes

Determining the Degree of [001] Preferred Growth of Ni(OH)\u3csub\u3e2\u3c/sub\u3e Nanoplates

Determining the degree of preferred growth of low-dimensional materials is of practical importance for the improvement of the synthesis methods and applications of low-dimensional materials. In this work, three different methods are used to analyze the degree of preferred growth of the Ni(OH)2 nanoplates synthesized without the use of a complex anion. The results suggest that the preferred growth degree of the Ni(OH)2 nanoplates calculated by the March parameter and the expression given by Zolotoyabko, which are based on the analysis and texture refinement of the X-ray diffraction pattern, are in good accordance with the results measured by SEM and TEM imaging. The method using the shape function of crystallites is not suitable for the determination of the preferred growth degree of the Ni(OH)2 nanoplates. The method using the March parameter and the expression given by Zolotoyabko can be extended to the analysis of block materials

Multiplex Limited Penetrable Horizontal Visibility Graph from EEG Signals for Driver Fatigue Detection

This work was supported by National Natural Science Foundation of China under Grant Nos. 61473203, 61873181 and the Natural Science Foundation of Tianjin, China under Grant No. 16JCYBJC18200.Peer reviewedPostprin

Wavelet multiresolution complex network for analyzing multivariate nonlinear time series

Z. K. Gao was supported by National Natural Science Foundation of China under Grant No. 61473203, and the Natural Science Foundation of Tianjin, China under Grant No. 16JCYBJC18200Peer reviewedPostprin

Bis{2-[(E)-benzyl­imino­meth­yl]-4-methyl­phen­olato-κ2 N,O}cobalt(II)

In the title complex, [Co(C15H14NO)2], the CoII atom, situated on an inversion centre, is coordinated by two O and two N atoms from two symmetry-related bidentate Schiff base ligands in a slightly distorted square-planar geometry. The two phenolate rings form a dihedral angle of 10.53 (2)°

The NTSC VLBI System and its application in UT1 measurement

In order to measure the Universal Time (UT1) in real time, National Time Service Center (NTSC) has built a VGOS-like (VLBI Global Observing System) broadband VLBI network, which includes three 13-m radio telescopes located in Jilin, Sanya and Kashi, and a data analysis center in Xi'an. Each station is equipped with a highly stable hydrogen atomic clock and a self-developed VLBI backend, and is co-located with two GPS receivers. This VGOS-like VLBI network may play an important role in improving the Chinese broadband VLBI technology and making valuable contributions to domestic VLBI measurements of UT1. In this paper, we introduce the specifications of this VLBI network, and present the UT1 measurements at C-band conducted in 2018 using the Jilin-Kashi baseline of this network. The comparisons between our UT1 estimates and those provided by IERS suggest that the NTSC VLBI network is capable to determine UT1 accurate at the level of 58.8 microseconds

Single-Atom Reversible Lithiophilic Sites toward Stable Lithium Anodes

Lithiophilic sites with high binding energy to Li have shown the capability to guide uniform Li deposition, however, the irreversible reaction between Li and lithiophilic sites causes a loss of lithiophilicity. Herein, the concept of using reversible lithiophilic sites, such as single-atoms (SAs) doped graphene, as a host, is systematically inspected in the context of Li metal battery (LMB) performance. Here, it is proposed that the binding energy to Li atoms should be within a certain threshold range, i.e., strong enough to inhibit Li dendrite growth and weak enough to avoid host structure collapse. Six kinds of SAs are utilized; doped 3D graphene, nitrogen-doped 3D graphene, and pure 3D graphene, whose performance in LMBs are compared with each other. It is discovered that the SA-Mn doped 3D graphene (SAMn@NG) has the most reversible lithiophilic site, in which adsorption strength with Li is suitable to guide uniform deposition and keep the structure stable. During Li plating/stripping, the changes of the atomic structures in SAMn@NG, such as change of bond length and bond angle around Mn atoms are much smaller than those on SAZr@NG, although its binding energy is higher, enabling a much-improved battery performance in SAMn@NG. This work provides a new insight to design lithiophilic sites in LMBs