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Supplementary Material 1

The DC distribution system has advantages over AC systems on power losses, control complexity, compatibility to DGs (Distributed Sources) and so on. The basic power flow problem in DC system is different from AC system in mathematical domain, bus types and component models. To construct the foundation of DC power system analysis, this paper analyzes the power flow problems in DC distribution system first, including bus types, power flow equations, Jacobian matrix and so on. It is pointed out that voltage regulation in DC power system only needs enough power capacity instead of generator with excitation system like AC system. Then, based on the DC bus voltage regulation property, the power flow path control and virtual topology reconfiguration technologies is proposed. The corresponding equivalent Jacobian matrixes are presented. Those technologies reveal that the DC power system can achieve much higher flexibility in power flow control. At last, simulation verification with MATLAB/SIMULINK is presented.

Flexible bearing is an important component of harmonic reducer which is widely used in automation equipment, especially in industrial robots. Studying its mechanical characteristics has great significance. In this article, the theoretical model of contact force between rolling elements and outer ring is established based on three bending moment equations, and the characteristics of CSF-40-80 flexible bearing are also studied by finite element method analysis. Analysis of equivalent stress at static state has shown that it already has large equivalent stress before load and that external load has a great influence on it. The dynamic and contact characteristics of it after actual assembly are also presented in this article. The displacements and velocities at different locations at different times of the movement are found to be different, which can provide a reference for the manufacture of flexible bearing.

The void underneath semi-rigid base is a common defect in roads. There are some difficulties in the detection and repair for this kind of hidden damage, as well as in the evaluation of the effects of grouting treatment. For the detection and maintenance of roads, it is essential to study the detection and judging for voids underneath base and the evaluation of the spread of grout. Through theoretical analysis, numerical simulation and analysis of real data, this research generated the characteristics of under-base voids of different types and dimensions on GPR images, proposed the detecting and dimension-measuring methods for under-base voids, and studied the process and effects of data analysis techniques. (1) The characteristics of under-base voids of different types (air-filled, water-filled or grout-treated) and dimensions (height and horizontal dimensions), on A-scan and B-scan GPR image respectively, were analyzed theoretically. (2) Approaches for detecting voids and for estimating its height were studied, focusing on voids with a height ranging from 0.01m to 0.3m. (3) The approach for estimating the horizontal dimension of voids was studied, focusing on voids with a length ranging from 0.04m to 0.52m. (4) The data processing process was discussed. Also, the effects of different data processing techniques were studied in terms of noise filtering and attenuation compensation, and their influence on the image characteristics was also discussed., Comment: Master's thesis, in Chinese

GpsB regulatory protein and StkP protein kinase have been proposed as molecular switches that balance septal and peripheral (side-wall like) peptidoglycan (PG) synthesis in Streptococcus pneumoniae (pneumococcus); yet, mechanisms of this switching remain unknown. We report that ΔdivIVA mutations are not epistatic to ΔgpsB division-protein mutations in progenitor D39 and related genetic backgrounds; nor is GpsB required for StkP localization or FDAA labeling at septal division rings. However, we confirm that reduction of GpsB amount leads to decreased protein phosphorylation by StkP and report that the essentiality of ΔgpsB mutations is suppressed by inactivation of PhpP protein phosphatase, which concomitantly restores protein phosphorylation levels. ΔgpsB mutations are also suppressed by other classes of mutations, including one that eliminates protein phosphorylation and may alter division. Moreover, ΔgpsB mutations are synthetically lethal with Δpbp1a, but not Δpbp2a or Δpbp1b mutations, suggesting GpsB activation of PBP2a activity. Consistent with this result, co-IP experiments showed that GpsB complexes with EzrA, StkP, PBP2a, PBP2b, and MreC in pneumococcal cells. Furthermore, depletion of GpsB prevents PBP2x migration to septal centers. These results support a model in which GpsB negatively regulates peripheral PG synthesis by PBP2b and positively regulates septal ring closure through its interactions with StkP-PBP2x.

The magnetic measurements have been carried out in single phase, polycrystalline superconducting sample---DyBa2Cu3-O7−x compound. The magnetization anomaly at 12–13 K range under the external magnetic field is observed and considered as the evidence of an antiferromagnetic ordering in this compound. From the experimental data of lower and upper critical fields, we deduce the crucial normal and superconducting parameters such as Hc (O); kGL; γ; λep; and etc. Using the Allen-Dynes strong e-p coupling Tc formula, we estimate the value of Tc and find a well coincidence with the experimental results. We believe that the phonon-mediated electron-pairing mechanism may be possible to explain the 90 K superconductivity.

The superconducting transition are determined by both resistance and AC susceptibility measurements in Dyx Ba1−xCuO3−y compound system. Their composition dependence has also been studied. We find that the zero-resistance temperature transition occurs at 94.1K for x=0.33 while X-ray diffraction analysis shows that it corresponds to a single phase which is an orthohombic perovskite structure with a =3.889 A , b =3.849 A and c =11.739 A .

The high-Tc superconductivity has been observed in SmxBa1−xCuO3−y compound system by both resistance and A.C. susceptibility measurements. The optimum composition is x=0.35 with zero-resistance transition temperature being 90.8K. The X-ray diffraction analysis indicates that this is an orthorhombically distorted perovskite structure with a =3.998 A , b =3.976 A and c =11.996 A .

An anomalous resistance drop was observed near 190K in the R-T measurement on a sample in Bi-Sr-Ca-Cu-O system and the transition completed at 80K. After keeping the sample at room temperature for 10h, the temperature dependence of the resistance changed from semiconducting to metallic behavior, while the ending of the transition remained at 80K. This might be an evidence of the existence of a metastable superconducting phase in Bi-Sr-Ca-Cu-O system with Tc as high as 190K.

In this paper, we report the I-V characteristics of rolling-quenched Al-Si-Ge strips. The results show the occurrence of voltage steps and hysteresis behavior in the superconducting transition region.