Parameter estimation and arrangement optimization of particle dampers on the cantilever rectangular plate

The particle damper as a passive means for vibration suppression, is preferred due to its simplicity and easy to implement and control, with no need for any auxiliary power equipment. The bottleneck of the design for the particle damper is that damping performance is influenced by many parameters including particle material and size, packing ratio and cavity dimensions of enclosure such as length, width and diameter. In fact, the overall damping effect of particle damper is closely related to the primary structure system parameters. However, the influences of the excitation point, dampers arrangements, excitation force amplitude, and excitation force type for overall damping effect are scarce reported in the open literatures. How to exert particle damper on the structure and how many particles filled within the cavity, which are needed to face the problem in the engineering practice. In the face of doubt above-mentioned, the above questions will be clarified in this paper. At the same time, an optimization algorithm by the application of genetic algorithms of BP neural network is carried out in order to get most excellent damping effect. These will offer significance guidance to design and conduct particle dampers implement in the specific engineering practice with reference significance

Localization, Globalization, and Traveling Chinese Culture

In their article Localization, Globalization, and Traveling Chinese Culture Chengjun Wang and Junhong Ma discuss three main channels of the traveling of Chinese culture to the outside world. Focusing on the situation of bilingualism (i.e., Chinese and English) and the need of spreading Chinese literature and culture especially in the English-speaking world, Wang and Ma argue for localization and globalization. Further, Wang and Ma argue that in order to narrow the gap of the cultural divide between China and the West. In addition to the need for bilingualism especially in the case of translation, they posit that especially the writing of the literary history of Chinese is needed in both English and Chinese (hence their argumentation with regard to bilingualism)

Time-varying influence of interest rates on stock returns: evidence from China

Whether a stock market should matter or not when monetary policy is concerned seems to be a controversial issue. The purpose of this study is to indicate whether the central bank should use monetary policy to help the stock market or not. Based on macroeconomic data such as interest rate and the stock market, we adopt a novel Bayesian time-varying regression model and determine that the impact of interest rate changes on stock returns varies over time in China, after controlling various macroeconomic factors. Although on average interest rates negatively impact stock price returns, they tend to have an abnormal positive effect at market high points, following a time-varying dynamic pattern. Surprisingly, during periods of overheated economic development, an increase in interest rates cannot suppress the rise in stock prices. Therefore, policymakers need to pay attention when accelerating the marketisation of interest rates and initiating the preventive role of timely and strategic adjustment of interest rates

Efficiency and risk in sustaining China’s food production and security: Evidence from micro-level panel data analysis of Japonica rice production

Sustainable food production and food security are always challenging issues in China. This paper constructs a multi-element two-level constant-elasticity-of-substitution (CES) model to assess technological progress in, and its contribution to, japonica rice production in China. The results show that the speed of technological progress in the production of japonica rice on average was 0.44% per annum in 1985–2013, and technological progress has contributed significantly to the growth of japonica rice production in China. Robustness checks show that the results appear to be sensitive to which sub-sample is used. Labour and some other inputs are found to be significant but negative, especially during the middle sampling period of 1994–2006 and in eastern and western regions. This has important policy implications on the impact of rural-to-urban migration and farmers’ human development. View Full-Tex

Thermodynamic properties of the itinerant-boson ferromagnet

Thermodynamics of a spin-1 Bose gas with ferromagnetic interactions are investigated via the mean-field theory. It is apparently shown in the specific heat curve that the system undergoes two phase transitions, the ferromagnetic transition and the Bose-Einstein condensation, with the Curie point above the condensation temperature. Above the Curie point, the susceptibility fits the Curie-Weiss law perfectly. At a fixed temperature, the reciprocal susceptibility is also in a good linear relationship with the ferromagnetic interaction.Comment: 5 pages, 5 figure

Probing phase transition in neutron stars via the crust-core interfacial mode

Gravitational waves emitted from the binary neutron star (BNS) systems can carry information about the dense matter phase in these compact stars. The crust-core interfacial mode is an oscillation mode in a neutron star and it depends mostly on the equation of the state of the matter in the crust-core transition region. This mode can be resonantly excited by the tidal field of an inspiraling-in BNS system, thereby affecting the emitted gravitational waves, and hence could be used to probe the equation of state in the crust-core transition region. In this work, we investigate in detail how the first-order phase transition inside the neutron star affects the properties of the crust-core interfacial mode, using a Newtonian fluid perturbation theory on a general relativistic background solution of the stellar structure. Two possible types of phase transitions are considered: (1) the phase transitions happen in the fluid core but near the crust-core interface, which results in density discontinuities; and (2) the strong interaction phase transitions in the dense core (as in the conventional hybrid star case). These phase transitions' impacts on interfacial mode properties are discussed. In particular, the former phase transition has a minor effect on the M-R relation and the adiabatic tidal deformability, but can significantly affect the interfacial mode frequency and thereby could be probed using gravitational waves. For the BNS systems, we discuss the possible observational signatures of these phase transitions in the gravitational waveforms and their detectability. Our work enriches the exploration of the physical properties of the crust-core interfacial mode and provides a promising method for probing the phase transition using the seismology of a compact star.Comment: 18 pages, 14 figure

High-Power and Ultralong-Life Aqueous Zinc-Ion Hybrid Capacitors Based on Pseudocapacitive Charge Storage

© 2019, © 2019, The Author(s). Rechargeable aqueous zinc-ion hybrid capacitors and zinc-ion batteries are promising safe energy storage systems. In this study, amorphous RuO2·H2O for the first time was employed to achieve fast and ultralong-life Zn2+ storage based on a pseudocapacitive storage mechanism. In the RuO2·H2O||Zn zinc-ion hybrid capacitors with Zn(CF3SO3)2 aqueous electrolyte, the RuO2·H2O cathode can reversibly store Zn2+ in a voltage window of 0.4–1.6 V (vs. Zn/Zn2+), delivering a high discharge capacity of 122 mAh g−1. In particular, the zinc-ion hybrid capacitors can be rapidly charged/discharged within 36 s with a very high power density of 16.74 kW kg−1 and a high energy density of 82 Wh kg−1. Besides, the zinc-ion hybrid capacitors demonstrate an ultralong cycle life (over 10,000 charge/discharge cycles). The kinetic analysis elucidates that the ultrafast Zn2+ storage in the RuO2·H2O cathode originates from redox pseudocapacitive reactions. This work could greatly facilitate the development of high-power and safe electrochemical energy storage.[Figure not available: see fulltext.]

A Pipeline VLSI Architecture for High-Speed Computation of the 1-D Discrete Wavelet Transform

In this paper, a scheme for the design of a high-speed pipeline VLSI architecture for the computation of the 1-D discrete wavelet transform (DWT) is proposed. The main focus of the scheme is on reducing the number and period of clock cycles for the DWT computation with little or no overhead on the hardware resources by maximizing the inter- and intrastage parallelisms of the pipeline. The interstage parallelism is enhanced by optimally mapping the computational load associated with the various DWT decomposition levels to the stages of the pipeline and by synchronizing their operations. The intrastage parallelism is enhanced by decomposing the filtering operation equally into two subtasks that can be performed independently in parallel and by optimally organizing the bitwise operations for performing each subtask so that the delay of the critical data path from a partial-product bit to a bit of the output sample for the filtering operation is minimized. It is shown that an architecture designed based on the proposed scheme requires a smaller number of clock cycles compared to that of the architectures employing comparable hardware resources. In fact, the requirement on the hardware resources of the architecture designed by using the proposed scheme also gets improved due to a smaller number of registers that need to be employed. Based on the proposed scheme, a specific example of designing an architecture for the DWT computation is considered. In order to assess the feasibility and the efficiency of the proposed scheme, the architecture thus designed is simulated and implemented on a field-programmable gate-array board. It is seen that the simulation and implementation results conform to the stated goals of the proposed scheme, thus making the scheme a viable approach for designing a practical and realizable architecture for real-time DWT computation

A Pipeline VLSI Architecture for Fast Computation of the 2-D Discrete Wavelet Transform

In this paper, a scheme for the design of a high-speed pipeline VLSI architecture for the computation of the 2-D discrete wavelet transform (DWT) is proposed. The main focus in the development of the architecture is on providing a high operating frequency and a small number of clock cycles along with an efficient hardware utilization by maximizing the inter-stage and intra-stage computational parallelism for the pipeline. The inter-stage parallelism is enhanced by optimally mapping the computational task of multi decomposition levels to the stages of the pipeline and synchronizing their operations. The intra-stage parallelism is enhanced by dividing the 2-D filtering operation into four subtasks that can be performed independently in parallel and minimizing the delay of the critical path of bit-wise adder networks for performing the filtering operation. To validate the proposed scheme, a circuit is designed, simulated, and implemented in FPGA for the 2-D DWT computation. The results of the implementation show that the circuit is capable of operating with a maximum clock frequency of 134 MHz and processing 1022 frames of size 512 × 512 per second with this operating frequency. It is shown that the performance in terms of the processing speed of the architecture designed based on the proposed scheme is superior to those of the architectures designed using other existing schemes, and it has similar or lower hardware consumption