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The factors which limit the usual techniques are many folded.
This inherent inadequacy of these fluids makes the heat removal mechanism less effective even with the best utilization of their flow properties.
Effective heat transfer improvement affects many different fields.
Nanoparticles velocity and temperature at the channel entrance is equal to the local fluid properties.
Geometry of the Microchannel Thermophysical properties of air and Al2O3 naoparticles are given in table 1.

Introduction More difficult machine materials have been developed with the advancement of both industry and technology due to their higher strength to weight ratio, heat resistant, tougher and hardness properties.
New advances in material science have produced high-tech ceramics, composite materials, and metallic engineering materials with excellent mechanical, thermal, and electrical conductivity properties that are well suited for spark erosion or electric discharge machining (EDM).
These research primarily focus on how the EDM process characteristics such as current, dielectric pressure, voltage, pulse on time, duty cycle etc., effect on machining properties like MRR, SR, Taper angle and TWR.
Perumal et al. [2] has conducted experiment on the basis of the Taguchi strategy approach to study the effects of machining factors like spark on time, discharge voltage and current.
Gugulothu [6] have been investigated on how process variables affect EDM of Ti-6Al-4V.

Improved surface properties (hardness, corrosion resistance) can be obtained using the LEHCPEB treatment.
As a result, improved surface properties of the material, often unattainable with conventional surface treatment techniques, can be obtained fairly easily.
This is particularly true for tribological [2,4,6,7] and corrosion properties [7-10].
The surface properties revealed in Fig. 1 must be determined by the final structure-phase states generated by the LEHCPEB thermo-mechanical treatment.
The so-formed homogeneous layers were demonstrated to improve the corrosion properties of these dual phase alloys; as illustrated in Fig. 1 for the 316L steel.

Artificial Neural Network Modeling of Injection Upsetting Load Prediction Önder Ayer1,a, Sedat Bingöl2,b, Tahir Altinbalik1,c 1Trakya University, Faculty of Engineering, Mechanical Engineering Department, 22180, Edirne, TURKEY 2Dicle University, Faculty of Engineering, Mechanical Engineering Department, Diyarbakır, TURKEY aonderayer@trakya.edu.tr, bsbingol@dicle.edu.tr, ctahira@trakya.edu.tr Keywords: Lateral extrusion, Injection upsetting, Artificial Neural Networks.
Mechanical and physical properties of the parts so manufactured are also high.
Albeit its advantageous as referred above the most important factor which limits the lateral extrusion is tool stresses.
One of the most important factor that affects the material flow is geometrical ratio of the primary deformation zone, another one is instantaneous die filling ratio.
That the areas in the die that have not been filled in are left at small amounts and that material flow to these small areas is very hard and difficult however is another factor which leads to increase of the load.

These changes will inevitably affect the existing PFA.
But some components’ properties may be changed (such as material properties) or replaced by an updated one.
They may be replaced by the updated one due to their material properties changes, process modification or structural optimization etc.
On the other hand, the PFA evolution is complex, and it involves in many factors.
The weight value of each influence factor, threshold value δ of degree of similarity and the threshold value ε of consumption quantity of component are all key factors which influence the PFA evolution outcome.

Some materials with excellent mechanical properties and corrosion resistance, such as stainless steel, are regarded as the ideal selections for preparation of metal working screen, but they cannot be shaped using electrodeposition technique..
Through-mask electrochemical micromachining (Through-mask EMM), which can process any metal materials regardless of their mechanical properties, has been preferentially applied to fabricate micro-& meso-scale hole array because of its some unique merits, such as short process time, good surface finish, and better controllability and flexibility.
Although, during through-mask EMM, undercutting dissolution is generally inevitable due to the isotropic nature of metal removal process, desired hole contour with good surface can be obtained by taking into proper consideration of some key factors including mass transport, current distribution and design of mask artwork[2,3].
Like Model-1, the change in composite mask thickness caused by either insulation mask or inert metal mask affects only magnitude of current density at each point of the workpiece surface.
Although it is also found that a favorable distribution profile of current density can be observed if only inert metal mask is applied, current densities on the workpiece are too small to etch metal electrochemically, resulting in an extremely low machine rate and a bad machining accuracy.In view of other factors, including etching rate, machining accuracy, mass transfer and mask fabrication, 0.05mm thick inert metal mask and 0.05mm thick insulation mask with a wall side angle of 45o of composite masks are selected in this study.

Carbide-derived carbon (CDC) films prepared on silicon carbide are known to have excellent tribological properties in dry nitrogen.
Acting as a solid lubricant, these carbon layers can be useful in applications such as bearings, SiC-based microelectromechanical systems (MEMS), electrical contacts, biomedical implants, and mechanical seals.The tribological performance of carbon is strongly affected by the environmental conditions of the test or application.
Carbide-derived carbon films have shown an opposite effect, with excellent frictional properties in dry nitrogen and moderately good in air.
The behavior of CDC in dry nitrogen may be explained by a number of factors.
However, onionlike structures are known to form in CDC films [13] and are associated with excellent frictional properties in MoS2 [14].

From a numerical point of view, pounding has been traditionally studied by either one of two models, that are: a) stereo-mechanical, or b) force-based.
The impact force can be evaluated by the following expression: Fpt,δ=khd∙x1t-x2t-gpn+chdt∙x1t-x2t x1-x2-gp>0 x1-x2>0 (3) Fpt,δ=khd∙x1t-x2t-gpn x1-x2-gp>0 x1-x2≤0 Fpt,δ=0 x1-x2-gp≤0 where the Hertz coefficient is assumed equal to n=32; the stiffness coefficient khd depends on both mechanical and geometrical properties of the colliding bodies.
Since it was observed that earthquake direction can affect the maximum response [14], both forward and backward seismic attacks were considered.
As can be gathered, given a seismic zone, the displacement amplification increases for decreasing mechanical characteristics of the foundation soil.
Response amplification factor α12 of mass-1, defined as multiplication factor of the non-pounding response of mass-2 are plotted in Fig. 5 against period ratio t.

During start-up of a hydrotronic system under thermal shock conditions elements of hydraulic components warm up in a non-uniform way, due to varying material and shape properties.
Determination of the Clearance Height in Cooperating Elements of Hydraulic Components During Start-up under Thermal Shock Conditions [4, 5] During start-up of a hydraulic system under thermal shock conditions elements of hydraulic components warm up in a non-uniform way due to varying material and shape properties.
The changes of clearance magnitude between cooperating elements of hydraulic components during actuation of device in aforementioned conditions depend on many factors, i.e.: load, ambient and oil temperatures, oil flow rate.
It is possible to evaluate the effective clearance during start-up period (τ) of the frozen component, on the basis of equation: )()()( ττ τ t pm e llll ∆−∆+= (1) Oil pressure affects both movable and immovable elements of the hydraulic component and generates deformation.
Jasiński: Methods of determination of correct operation area for hydraulic component in low ambient temperatures, Developments in Mechanical Engineering, vol. 2, Gdańsk (2008) [4] R.

Eq. (5) can also be written in terms of the natural frequency and the damping factor
Therefore, the frequency of these period functions depends upon the mechanical vibration.
Unless otherwise specified, the material properties and dimensions of the FSCBVT harvester in the simulations are listed in Table 1.
Material properties and dimensions of the energy harvester Basis layer E rb b L M (N/m2) (kg/m2) (m) (m) (kg) 200*109 7.8 *103 0.01 0.1 0.1 Piezoelectric layers C11 rp e31 e33 (N/m2) (kg/m2) (C/m2) (nF/m) 2* 109 2.4* 103 -5.8 4.956 Fig. 3(a) shows the effect of h0 on the natural frequency of the cantilever harvester, and the parameter in this simulation is set to be hp=0.2mm.
Because the parameter is affected by the geometric parameters of a FSCBVT harvester, we analyse the impact of geometric parameters on the inherent electromechanical coupling parameter.