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Introduction Copper matrix composites have the potential for use as wear resistant and heat resistant materials; brush and torch nozzle materials and for applications in electrical sliding contacts such as those in homopolar machines and railway overhead current collector systems where high electrical/thermal conductivity and good wear resistant properties are needed [1, 2].
Several factors that affect machinability are work-piece related (mechanical properties, microstructure), tool related (strength, geometry), and machine related (accuracy, force requirements, surface roughness, chip morphology) [10].
The surface qualities of a workpiece are essential not only for dimensional accuracy and aesthetics, but also for other physical and chemical properties such as fracture toughness, corrosion resistance, and fatigue life.
Feed rate was an influential factor in determining sampling length.
Looking at the parameters affecting the surface roughness in the machining of composite materials it is possible to say that cutting parameters have a significant effect.

Results indicated that the frictional factor and the wear rate of nanometric ZrO2 ceramics decreased significantly under identical working and frictional conditions compared with ZrO2.
However, its high fragility and low strength restricted its application in the weight-bearing parts in the human body, so the selective addition of second-phase particles and whiskers as well as other methods were adopted to improve its mechanical properties.
Xu Shuhua and Huang Chuanyong also made studies on the microstructures and properties of HA-ZrO2 composite materials.
He believed that the phase-transition ZrO2 toughened ceramics had better mechanical properties than other dental ceramics, and its chemical stability also met the requirement when it was used as dental ceramics.
Quinn et al. studied the effects of microstructures and the chemical composition on the mechanical properties of dental ceramics and also believed that ZrO2 ceramics possessed better mechanical properties as dental ceramics.

Introduction Generator is a kind of mechanical equipment that converts other forms of energy.
In the process of curing and heating of stator coil, the curing curve is divided into three sections, one group of heating curing curve showed as Fig.1: Fig. 1 Solidification curve of stator bar Firstly, we analyzed epoxy resin from physical properties [4].
We found three-stage heating curve meets the requirements of the gelling process of epoxy resin: Through the three-stage curve, adverse effects caused by the heating of the epoxy could be lowered to the minimum, also, make the temperature of the bar cold down to the curing temperature slowly; From the analysis of automatic control theory, the set value for ramp function, the overshoot of the system will be greatly reduced, environmental factors, coupling factors such as disturbance of the system will be reduced too, the heating temperature will be coincide with the given temperature better.
Based on the above analysis, the most important processing parameters of generator stator bar are t1, T2, t1, T2 these four parameters, these four parameters directly affect the final processing results of the wire rod.
Analyzing how these two parameters affect bar’s dielectric loss is same as researching how they affect last processing effect.

The analysis of the scientific literature was made at the base of theoretical considerations about the problems that have been encountered with hip resurfacing prosthesis and the factors that could affect the clinical performance of the hip resurfacing prosthesis.
These problems will be discussed below in details after a concise analysis of the factors that could affect the clinical performance and the risk of fracture in the case of hip resurfacing arthroplasty.
These factors could be classified in: patient, surgical, and postoperative factors.
Patient factors included sex and proximal femoral bone quality.
The manufacturing processes will modify not just the alloys structure and consequently the properties (like influence on the incidence of hypersensitivity responses), but also the surface.

However, analyzing the stability and vibrations it is also important to consider the drill string in the form of a cylindrical shell which is affected by diverse loadings and factors of the environment.
This property qualitatively distinguishes the behaviour of shells at the loss of stability from the behaviour of rods and plates.
We analyzed the influence of shell's length, pressure of a gas flow, material properties and compressing load on the magnitudes and modes of shell vibrations.
As a result, it was found out that the second and third modes substantially affect the nature of undulation in the median surface of a shell.
Advances in Mechanical Engineering (2014)

Introduction A large number of experimental results have confirmed that mechanical properties of rocks are anisotropic, such as the tensile/compressive strength [1], drillability [2,3], fracture toughness [4], and so on.
Anisotropy is a common property of many typically rocks [5].
SPE 16658, 1987 [7] A Lubinski, Woods H B., Factors affecting the angle of inclination and dog-legging in rotary bore holes.

In a broader sense, however, the quantified value of any factor that affects the process can be regarded as a parameter.
Another major factor affecting shell thickness and liquid pool length is overheating.
In cases of solidification ending in columnar dendrites or a very small zone of equiaxed dedritic zone, excessive segregation results in compromised mechanical parameters at the places that solidified last.
The chemical analysis of carbon and sulfur content, as well as the evaulation of metallographic structure and mechanical properties (by tensile and impact testing) in these points would be done for verification of the program.

Currently, Paul Geraghty of LLNL and François Guillet of France have developed corresponding devices for different mechanical mitigation technology respectively[3,4].
The spindle fixture and axis Z are connected by bolt joints, so the vibration generated from the high-speed rotation movement of the spindle will affect the stability of the moving axis, and thus indirectly affect the processing quality.
Considering the input properties of drivers and the need of high-precision feed amount, a kind of velocity&acceleration feed forward control strategy with Notch filters based on the traditional PID control algorithm is applied to the system of machine tool.
Depending on the corrector loop type selected, the level of this output voltage can be the result of two gain factors, the PID corrector and the feed forward loop.
Chun-Hong, Modelling vibration transmission in the mechanical and control system of a precision machine[J].

Experimental Research on Microelectroforming with Ultrasonic Agitation Pingmei Ming1,2,a , Di Zhu 2,b , Yangyang Hu2,b and Yongbin Zeng2,b 1 School of Mechanical and Power Engineering, Henan Polytechnic University, Jiaozuo, China 2 College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China a mpm@hpu.edu.cn; bDZhu@nuaa.edu.cn Keywords: Microelectroforming, Ultrasonic agitation, Microdevices, Surface topography Abstract.
Ultrasonic agitation or vibration of electrode (anodes or cathode) is frequently considered to solve the problem of mass transport limitation during electrodeposition of metals within deep, high-aspect-ratio features, for it is beyond most traditional agitation-techniques used today by providing both increased mass transport of reactive species to the cathode as well as mechanically affecting the electrochemical reactions taking place on the cathode.
Conclusions that ultrasound use clearly affected deposit properties and coating mechanisms, such as catalyst specific area, stirring dependence, surface energy evolution, dihydrogen desorption, and structure of coating, were obtained in the document [3].
(a) Air pump agitation (P=0) (b) Ultrasonic agitation (P= 4W/cm 2 ) (c) Ultrasonic agitation (P= 6W/cm 2 ) (d) Ultrasonic agitation (P= 8W/cm 2 ) (e) Ultrasonic agitation (P= 10W/cm 2) (f) Ultrasonic agitation (P= 12W/cm 2) (g) Ultrasonic agitation (P= 14W/cm 2 ) (h) Ultrasonic agitation (P= 16W/cm 2 ) Fig.2 Deposit morphology caused by air pump agitation and high frequency sonication of different level of power intensities The observation of these disparities between surface morphologies is believed to be attributed to the following factors: (1) mass transport rate with the use of ultrasonic agitation is much higher due to the acoustic streaming serving as local mass transport pumps for ions and other species in the electrolyte near the cathode surface, which narrows the extension of diffusion-transport and reduces concentration gradients, and this effect increases with the increasing of power sonication[2,6]

Micro-Opto-Electro-Mechanical System (MOEMS) has the advantages of small size, light weight, little energy consumption, high reliability, high-volume production and so on.
The detection principle of traditional sensors is adopted, i.e. physical laws and physical property changes.
MEMS (Micro-Electro-Mechanical System) manufacturing technology is used.
The miniaturization on the geometric size of micro-sensor not only maintains its original sensing properties, but also improves its temperature stability, which makes it less susceptible to the interference of outside temperature.
The basic model of passive accelerometer Using Laplace transform, the transfer function from acceleration to the displacement of mass can be gotten (4) Where, is the resonant frequency; is the quality factor.