In order to realize the memory cutting of a shearer, made use of the memorizedcutting path and acquisitioned cutting parameters, and realized the teaching and playbackof the cutting path.In order to optimize the memory cutting path of a shearer, took intoaccount the constraints of coal mining craft, coal quality and the adaption faculty of coalmining equipments.Genetic algorithm theory was used to optimize the memory cutting ofshearer and simulate with Matlab, and realized the most valuable mining recovery rate.The experimental results show that the optimization of the memory cutting path of ashearer based on the genetic algorithm is feasible and obtains the most valuable memorycutting path, improving the ability of shearer automatic cutting.
Isolating reductive silver kernel from shell is a challenging task but is quite important to understand the embryonic form during the formation of silver nanoclusters.The intercalation of suitable anionic species may be of benefit for passivating then capturing such highly active kernel.Herein,we successfully isolated a novel silver thiolate nanocluster[Ag_(13)@Ag_(76)S_(16)(Cyh S)_(42)(p-NH_(2)-Ph As O_(3))_(4)]^(3+)(SD/Ag89 a,Cyh SH=cyclohexanethiol)that contains a well-isolated icosahedral Ag_(13) kernel passivated by four Ag S_(4)^(7-) tetrahedra and four p-NH_(2) Ph As O_(3)^(2-) piercing from outer Ag_(72) shell.Of note,this Ag_(13) kernel is the largest isolable subvalent silver kernel beneath the silver shell with extremely legible core-shell boundary ever before and represents a precise embryonic model formed in the reducing Ag(I)to Ag(0)followed by aggregating to large silver nanoparticles.The reductive role of DMF and the introduction of anionic passivation layer(APL)synergistically modulate the reduction kinetics,facilitating the capture of ultrasmall subvalent silver kernel.SD/Ag89 a emits in near infrared(NIR)region(λ_(em)=800 nm)at low temperature.The synthetic strategy shown in this work opens up new opportunities for precisely capturing and recognizing diverse reductive silver kernels in different systems.
In this paper,the authors can prove the existence of translating solutions to the nonparametric mean curvature flow with nonzero Neumann boundary data in a prescribed product manifold M^(n)×R,where M^(n) is an n-dimensional(n≥2)complete Riemannian manifold with nonnegative Ricci curvature,and R is the Euclidean 1-space.
High performance can be obtained for the integrated power electronics module（IPEM） by using a three-dimensional packaging structure instead of a planar structure. A three- dimensional packaged half bridge-IPEM （HB-IPEM）, consisting of two chip scale packaged MOSFETs and the corresponding gate driver and protection circuits, is fabricated at the laboratory. The reliability of the IPEM is controlled from the shape design of solder joints and the control of assembly process parameters. The parasitic parameters are extracted using Agilent 4395A impedance analyzer for building the parasitic parameter model of the HB- IPEM. A 12 V/3 A output synchronous rectifier Buck converter using the HB-IPEM is built to test the electrical performance of the HB-IPEM. Low voltage spikes on two MOSFETs illustrate that the three-dimensional package of the HB-IPEM can decrease parasitic inductance. Temperature distribution simulation results of the HB-IPEM using FLOTHERM are given. Heat dissipation of the solder joints makes the peak junction temperature of the chip drop obviously. The package realizes three-dimensional heat dissipation and has better thermal management.
