In the context of the new round of industrial revolution, how to accelerate industrial transformation and upgrade and enhance Guangzhou's industrial competitiveness is an urgent problem to be solved. Based on the "Bow String Arrow" model, focus is turned on the new concept and new orientation of Guangzhou's industrial development, aiming to provide a comprehensive and scientific evaluation model for the regional competitiveness level, and the following conclusions are drawn:(1) for the traditional "Bow String Arrow" model, bows, strings, and arrows mean hard elements, soft elements, and main grippers, and except for the collaboration of bow and strings, the target and the bull's eye and the professionalism of the athletes are three indispensable elements, namely, development orientation, industrial synergy development and governance level of management; (2) an "internal drive mechanism" needs to be constructed for cultural development, ecological synergy and innovation for the industrial development of Guangzhou in the new era; (3) the development of regional competitiveness in Guangzhou requires the advantage of the Internet and international production capacity. With new R&D institutions and disruptive technologies as breakthroughs, characteristic towns will be created and industrial integration promoted.

Taking the literatures from the database of China National Knowledge Internet as the research objects and using bibliometrics method, based on citespace, the research on the transformation and upgrading of domestic manufacturing industry are visually analyzed from the aspects of paper publication, highly cited literature analysis, research hotspots and evolution trends. Through analysis, it is found that the domestic manufacturing transformation and upgrading research can be clearly divided into three stages, namely, 1998~2003, focusing on manufacturing development under the background of industrial restructuring, technological innovation, and economic growth; 2004~2007, focusing on equipment manufacturing industry, productive service industry, industrial clusters and global value chain; and from 2008 to the present, research hotspots having two characteristics. Before 2011, the focus was on the transformation and upgrading of industries or manufacturing industries. After 2011, the focus was on the research under the new environment of economic development, such as new normal, China Manufacturing 2025. On this basis, in-depth analysis is conducted on each stage of research and formation reasons, in order to provide reference for the relevant research on the transformation and upgrading of domestic manufacturing.

Silicon nitride ceramic ball is the key element of bearings in heavy equipment, and the ultra-precision grinding and polishing quality of the balls is an important factor affecting the bearing performance and life. From the angle of the processing method, the research progress of ceramic ball grinding and polishing technology is summarized. The method of ultra-precision compound polishing for different silicon nitride ceramic balls is compared and analyzed. A new method of grinding and polishing, that is, the method of cluster magnetorheological polishing, is put forward. Preliminary tests show that by the method of 3 hours of polishing, silicon nitride ceramic ball surface roughness Ra can reach 5 nm, and sphericity is 0.11 to 0.22 μm.

A three-degree-of-freedom (2R1T,R denotes rotation, T denotes translation) spheroid parallel mechanism that can be applied in the field of electronic assembly is proposed. The mechanism is composed of two equal-radius moving platform and base which are connected by three identical RSR (R denotes rotational pair, S denotes spherical pair) branches. The moving platform and the base are always symmetrical about a middle plane during the movement, and the moving platform can rotate around any lines within the plane of symmetry and translate along the center line of the two platforms. Based on the special geometric symmetry of the mechanism, its equivalent kinematics model was established. Then the dynamic model of the mechanism was established by using the Lagrange method. Through specific motion examples, the dynamics were validated using Mathematica calculations and ADAMS (Automatic Dynamic Analysis of Mechanical Systems) simulations. The correctness and validity of the learning model provide theoretical guidance for further research on the dynamic characteristics of the mechanism and system motion control.

The traditional vehicle design and optimization relies on the expert knowledge which leads to long development cycle, mass consumption of human resources and materials. In addition, this kind of method also determines that it cannot meet the market demand. The development of the finite element method provides a solution for vehicle structure design and optimization. Aiming at improving the handling stability and the structure safety, this research focuses on the lightweight design of a coach chassis. Firstly, a finite element model and its simplified model are constructed based on the finite element method. In this connection, the loading mode and working condition are defined. By combining the practical engineering situation, the chassis structure is modified and the objective function, cost function and variables are defined, and the proposed scheme for lightweight design of the coach chassis is proposed. The modal analysis, stress analysis and deformation analysis of the proposed scheme under bending condition, braking condition and steering condition are verified. The results show that the proposed lightweight design scheme effectively solves the lightweight optimization of the coach chassis based on the dynamic performance of the vehicle, as well as improving the handling stability and the structure safety.

The wireless power transfer (WPT) is a controllable and promising way to solve the energy scarcity problem of the devices in wireless networks. The non-orthogonal multiple access (NOMA) scheme is a new multiple access technique, which has been proposed to provide higher spectral efficiency (SE) and support massive user accesses. A wireless powered NOMA network consisting of one multiple-antenna power station, multiple single-antenna users and one single-antenna information receiver is considered. In the downlink, the power station transfers wireless energy to the users, while in the uplink, the users transmit their information to the information receiver in the NOMA manner. A practical scenario where the power station knows imperfect channel state information (CSI) of the downlink channel is viewed, and a robust resource allocation algorithm is proposed to jointly optimize the beamforming of the power station, the transmit powers of the users, and the time lengths of the downlink and uplink in order to maximize the throughput of the system. Simulation results show that the proposed robust design algorithm achieves significantly higher throughput than the non-robust benchmark scheme.

In order to solve the problems of endfire, miniaturization and broadband of the micro-Doppler effective radar, a compact broadband endfire array antenna is proposed.The four T-slotted antenna elements are symmetrically placed on the back of the substrate, and the feeding network is located on the front of the substrate, thus forming a coupling feed, which has same amplitude and the distribution of phase in the clockwise direction is 90°, 270°, 0°, 180°.After processing and measurement, the measured results are basically consistent with the simulated results, and the operating frequency band is 5.72~6.71 GHz, which has the absolute bandwidth of 0.99 GHz and satisfies the requirement of wideband characteristic.The antenna adopts an easy-to-integrate miniaturized planar design, and has broadband characteristic, good endfire performance, low processing cost, which can meet the practical application requirements of the micro-Doppler effective radar.

The moisture characteristics and microstructure of soft soil are the key factors in determining the physical and mechanical properties of soil. The relaxation time T₂ spectra and scanning electron microscope images of soft soil from Nansha District were obtained by means of nuclear magnetic resonance (NMR) and scanning electron microscopy (SEM). The water phase and pore size distribution of two types of soft soils were summarized based on SEM and NMR test results. The results show that the relaxation time T₂ distribution curve of Nansha soft soil is bimodal with two kinds of water in soil, the first state water being over 99% of the total water quality, and muck and mucky soil having many small pores mainly concentrated in the range of 0.1 μm to 20 μm. SEM images show that the three microstructure types of Nansha soft soil are in flocculent microstructure, honeycomb microstructure and clot microstructure. These methods also can calculate the microstructure parameters such as average pore radius, average pore area, surface porosity, pore shape factor and pore fractal dimension. The results of pore sizes obtained by the two methods are basically the same, but not completely consistent. Finally, the characteristics of the two methods and several issues in the application of SEM and NMR test are discussed.

Due to the anisotropic characteristic of natural soils, their effects should be considered in slope stability analysis. For soils, the expressions of shear strength parameters c and φ are proposed by incorporating an anisotropic state scalar parameter which is a joint invariant of material fabric tensor and normalized deviatoric stress tensor, and the validity of the formula is verified by existing test results. The formula of anisotropic strength parameter is applied to slope stability analysis and a large number of calculations are performed. The results show that slope safety factor can be reduced by 22.0% after considering the anisotropy of strength for the gentle slope with an angle of 14°. When the slope angle is increased to 55°, the relative difference of safety factor in isotropy and anisotropy is slightly more than 8.0%. It indicates that the anisotropy of soil strength has a greater impact on the gentle slope than on the steep slope, especially for high and gentle slopes, which deserves attention.

Difference of arch rib stiffness based on two concrete-filled steel tube arch bridge standard of GB 50923-2013 and JTG/T D65-06-2015, 15 groups of steel tubes and concrete according to the method of two specifications were calculated. In order to analyze rationality of the two specifications of arch rib stiffness, the FEM analysis of ANSYS was used to simulate a single arch rib. Finally, a standard steel tube concrete arch bridge was used to establish the finite element model and analyze the influence of horizontal bracing on its stability. The results indicate that the error of the calculation result of the rigidity of the arch rib is within 10%. The single arch rib simulated by ANSYS using the unified theory is more convenient and faster than using the double-element method, and the result of simulation is more consistent with the test result. The stability coefficient of arch bridge by using "X" brace is 4.3%, 0.6% and 17.8% higher than that of "H" brace, "K" brace and "一" brace respectively. When the number of bracing increased from zero to 2, the stability coefficient of standard CFST arch bridge increased by 41.2%, and the rate of increase was the highest. The number of bracing continued to increase, while the improvement rate of stability coefficient decreased. The bracing built between the span of 1/4 and 5/8 can make the stability of CFST arch bridge achieve the best effect.

To make the best use of talents, to ensure and improve the quality of service, and to save the operating costs of enterprises, the division of labor of mobile communication base stations is optimized based on multi-station and multi-task constraints. Combining the "Role-Based Collaboration" engineering theory method with its E-CARGO model, the sub-division task division of the base station is modeled; combined with historical simulation data, the Group Role Assignment method is used to make first the one-to-multiple stagnation point assignment for the maintenance personnel, and then the many-to-many division of labor assignment. Through an experimental simulation, the method is proven efficient and reliable, which enables the generation team to maximize the execution force under multi-station and multi-task constraints, thus providing effective support for human resource decision makers.

To deal with noise reduction of kernel fuzzy spectral clustering for obtaining a better cluster capability, a new spectral clustering based on local outlier factor was presented. With the proposed method the distribution features of outliers were analyzed. Based on the analysis result, the cluster center candidate object was proposed by using local filter factor algorithm. And then a process was constructed to filter the noise data and highlighted normal data's influence in the clustering center adjustment. Secondly, the local filter factor was presented by using local outlier factor between two arbitrary objects. Then the local filter factor was used as weighting factor to improve the similarity measure of kernel fuzzy spectral clustering. The improved similarity measure made weight between normal data and normal data became bigger and weight between normal data and noise data smaller. Therefore, the improved kernel fuzzy spectral clustering can reduce greatly the sensitivity of outliers. The validity experiment and stability experiment results show the proposed method has better clustering accuracy and robustness.

An approach for failure prediction for stochastic DESs modeled by stochastic finite state automata is proposed. Firstly, the notion of predictability of failure events of stochastic systems is formalized. Then a predictor automaton is constructed by introducing the probability transition matrix, and a necessary and sufficient condition of the predictability of stochastic systems is presented. Based on the fault predictor, a method for checking whether the considered stochastic DES has been equipped with the capability of failure prediction is developed by computing the extended Markov matrix, which results in the realization of accurate prediction of the failure events before occurring.

The objectives of this study are to investigate the fluxes of N₂O from urban wetlands, and to find the related environmental factors. The enclosed static chamber-gas chromatography method is used to analyze the N2O fluxes of Canna indica (CI), Colocasia tonoimo (CT) and Aphelandra ruellia(AR) from December 2013 to November 2014 in the typical urban wetland of the Haizhu Lake in Guangzhou City. The results shows that the average annual fluxes of N₂O in the water-free areas are 0.029 mg·m^-2·h^-1 for CI, 0.089 mg·m^-2·h^-1for CT, and 0.013 mg·m^-2·h^-1 for AR, and are 0.016 mg·m^-2·h^-1 for CI, 0.0069 mg·m^-2·h^-1for CT, 0.022 mg·m^-2·h^-1 for AR in the water areas. Differences in N₂O fluxes between different seasons are obvious. Water level and temperature are significant factors affecting N₂O emission, while the influence of different plants community type is not significant. The N₂O emission flux goes to the largest when the temperature is at 25~35℃.

To investigate the anti-aging effect of compound oral liquid of astragalus on skin, SD rats were randomly divided into medicated serum group and non medicated serum group and given compound oral liquid of astragalus and saline solution at the dose of 10 ml·kg^-1 once a day by intragastrical administration for 7 days, respectively. Firstly, 10% serum was added to senescence of human fibroblasts model which had been treated with 200 nM mitomycin (MMC) for 48 h. The experiment confirmed that medicated serum group has a significant role in promoting the proliferation of fibroblasts. Secondly, the expression of filaggrin in Episkin and collagen types I and Ⅲ in three-dimensional dermal aging model was evaluated after being treated with serum by immunofluorescence staining and Elisa kit, respectively. The results shows that compound astragalus oral liquid is helpful to the expression of filaggrin in epidermis to improve the function of skin barrier and water retention capacity, and collagen types I and Ⅲ to enhance mechanical properties of skin and reduce wrinkles. In conclusion, compound oral liquid of astragalus shows good effect of anti-aging on skin.

Styrene (St) and 4-vinylpyridine (4VP) were used as monomers to prepare a series of mPEG₄₅-P(St-co-4VP)/P(St-co-4VP) polymer nano-objects of different morphologies in methanol/water at 70℃, mediated by binary mixture of mPEG₄₅-DDMAT and DDMAT. Effects of[St]₀/[4VP]₀ molar ratio, degree of polymerization (DP) of the core-forming block,[mPEG₄₅-DDMAT]/[DDMAT] molar ratio on the assemblies were investigated by transmission electron microscopy (TEM), scanning electron microcopy (SEM) and ¹H NMR spectroscopy.