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Aiming to deal with thermal error of NC machine tool which can cause reduce of machining accuracy, this paper uses an external error compensation which interacts with NC controllers and PMAC multi-axis and then revises the tool path by adding the error tested in real-time by PMAC card. The processing accuracy is improved eventually. This method can compensate machine geometric errors and thermal errors in real-time. Comparing with other methods of error preventing, this method is more effective and affordable.

We present a newly developed algorithm for three-dimensional (3D) magnetotelluric model based on the vector finite element method. In this paper, unstructured grids which are composed of irregular tetrahedrons are used in our finite element model, which can be refined locally and adaptively according to the complex geometry of computational domain or subsurface structure. For obtaining more accurate solutions, secondary field rather than total field is numerically computed, which makes the errors limited to relatively small secondary field. Traditional node-based finite element method does not satisfy the condition that the normal electrical field is discontinuous at the interface of electric separatrix and the electrical current density is divergence-free throughout the regions without source, which obviously violates Maxwell equations. In order to overcome these drawbacks of node-based finite element, vector finite element method is employed to solve the secondary field-based partial differential equation. Moreover, in this study, the heterogeneous permeability is taken into consideration in our algorithm, as a consequence, which can deal with heterogeneous permeability model. The accuracy of our approach is verified by comparing with previously published numerical simulations of a COMMEMI-3D model. The advantages of our approach are also illustrated by the numerical simulations of model with arbitrary topography and complicated anomalous body. In addition, the simulation results of the irregular anomaly and the complex model of arbitrary terrain are both ideal results. It proves that the effect of 3D terrain is more serious and complex than that of two-dimensional (2D) terrain, and dealing with 3D models or data with 2D algorithm may bring in large errors. In the area where the magnetic permeability is abnormal, the magnetic permeability has an important influence on the numerical simulation results, and the magnetic permeability must be treated as an independent parameter in the magnetotellurics survey.

The total reflection of the wave will occur twice and the lightning over-voltage will be increased by 2 times when the lightning wave along the line reached in the disconnect switch are derived through the analysis of the accident 66kV transformer insulation breakdown. This will lead to the switch breakdown and discharge to be grounded. In this case the breaker is between the arrester and the transformer and the transformer will withstand 2 times arrester residual voltage result in the transformer breakdown. Finally, effective preventive measures combined with the practical experience are proposed.

A wearable-optimized implementation of a sleep stage classification algorithm that has low detection latency, high detection accuracy and low resource consumption is developed and successfully implemented on a low-power FPGA microsystem for closed-loop electrical brain stimulation. This implementation uses EEG and EMG signals as inputs and classifies stages of sleep. By structurally merging multichannel FIR and window averaging filters into one reconfigurable, multipurpose filter, the new implementation maintains a sleep detection accuracy of 79.7%, a REM detection sensitivity of 98.2%, a REM detection specificity of 89.2% and a detection latency of 0.982 ms, while consuming 6.8 times fewer logic elements and 96.28% less power compared with the current state of the art implementation. With its high performance and low resource usage, this implementation enables a low-power wearable microsystem to perform neural recording, real-time REM sleep stage detection, and closed-loop responsive brain stimulation as a tool to study the mechanisms of neurodegenerative diseases.

A control strategy which based on minimum instantaneous equivalent fuel consumption was proposed in this paper. The important parameters that affected the calculation of instantaneous fuel consumption were analyzed. The important parameters include battery equivalent fuel consumption, penalty function to maintain the battery SOC and the revise of the regenerative braking energy. More precise expression of minimum instantaneous fuel consumption was deduced. Under the simulation platform of ADVISOR software, orthogonal optimization of parameters was performed and the range of important parameters in the optimization of expression was determined.

The equivalent salt deposit density (ESDD) is an important characteristic of our country which is used to measure insulator deposition level. The contamination of the insulator would reach saturation after a period of time.In order to increase the specific creepage distance, disc suspension porcelain insulator lower surface inward concave, which makes the rain washing the upper surface difficult, that cause the saturation time of lower surface longer than upper surface .For studying the operation insulator contamination saturation time and reflecting the ESDD of the actual operation line accurately,this paper adopts a comparison method between empty hanging insulator surface and operation insulator surface to measure the ESDD , the field experimental results further verify that the saturated time of disc suspension insulator lower surface is longer, so as to lay the foundation for the ESDD measurement.

This paper discusses the application research on high-tech tax preference policy of manufacturing. Analyzing high-tech tax preference policy of the current manufacturing;The disadvantages of high-tech tax preference policy in production manufacturing;Suggestions for further implementing the high-tech tax preference policy of manufacturing.

Juniperus pingii (Ping's juniper) is a threatened conifer species endemic to China, and a good knowledge of its population genetics would be essential to formulate effective conservation strategies. In this study, ten polymorphic microsatellite loci were isolated, and characterized for their utility using 58 individuals from two geographically distinct populations. In population XGLL, the number of alleles per locus (N (A)) ranged from four to 11, with an average of 6.2 per locus; the observed (H (O)) and expected heterozygosity (H (E)) ranged from 0.205 to 0.854 and from 0.423 to 0.754, with an average of 0.347 and 0.527, respectively. In population BM, N (A), H (O) and H (E) ranged from four to eight, from 0.198 to 0.454 and from 0.339 to 0.853, with an average of 5.8, 0.294 and 0.556, respectively. Following the sequential Bonferroni correction, only one locus (Jp07) was found to deviate significantly from Hardy-Weinberg equilibrium within population XGLL, and no significant linkage disequilibrium was detected in any of these loci within either population. These polymorphic microsatellite loci would be useful for population genetic studies of this conifer species.

A digital pulsar backend based on a Field Programmable Gate Array (FPGA) is developed. It is designed for incoherent de-dispersion of pulsar observations and has a maximum bandwidth of 512 MHz. The channel bandwidth is fixed to 1 MHz, and the highest time resolution is 10 μs. Testing observations were carried out using the Urumqi 25-m telescope administered by Xinjiang Astronomical Observatory and the Kunming 40-m telescope administered by Yunnan Observatories, targeting PSR J0332+5434 in the L band and PSR J0437–4715 in the S band, respectively. The successful observation of PSR J0437–4715 demonstrates its ability to observe millisecond pulsars.

Three compounds, 20-O-acetyl-[3-O-(2'E,4'Z)-decadienoyl]-ingenol (1), 20-O-acetyl-[5-O-(2'E,4'Z)-decadienoyl]-ingenol (2) and 3-O-(2'E,4'Z)-decadienoylingenol (3), were isolated from Euphorbia kansui under the bioassay-guided method. Each compound showed the same antinematodal activity against the nematode, Bursaphelenchus xylophilus, at a minimum effective dose (MED) of 5 microg/cotton ball.