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The realization of HAMR involved some challenges from both optical design and media properties [3, 4].
It is based on the fact that the drastic decrease of the intrinsic magnetic properties of the medium (saturation magnetization Ms, anisotropy field, and coercive field Hc) when the temperature T of the media is increased.
Nevertheless, the lattice structure and the magnetic properties of the FePt-based alloys, correlated by the spin-orbital interaction, are affected by thermal agitation and, therefore, the heating and cooling issues are very important factors for HAMR media in both static and dynamic aspects [1].
Nevertheless, the technology based on lithography and nanoprinting involves the process of etching to form the magnetic bit, which damages the bit, thus affecting the magnetic anisotropy (and therefore the thermal stability) and increasing the switching field distribution.
A good choice of the layers separating the recording layer from the substrate (interlayer, seed layer and heat sink layer) is crucial from the viewpoint of the thermal design of HARM media so more as this design must take into consideration the magnetic, structural and even mechanical properties of the media configuration.

The formation mechanism and developmental properties of talus are analyzed in this paper.
It belongs to special weak surrounding rock, and easily affected by groundwater.
Fig.1 Talus forming process Through consulting the rock survey and geological data, obtains talus forming process of ZhaoTong in Yunnan Province: (1) In the process of crustal plates movement, the basin tectonic compression and uplift that lead to the formation of steep mountains; (2) In the inverse slope side, rock fracture exposed and the alternating structure of weak mud stones and hard rocks (sandstone or limestone) formed; (3) Due to the weak mud stone easy to weathering, chipping blocks along the slope rolled gradually accumulate in the toe or prominent slope station; (4) The impending hard rock under the action of external force and weathering fracture rolled along the slope depositing and mixing with weathered soft rock material; (5) With the increase of the deposit, and under the influence of factors , such as rainfall, talus gradually became thick, and may form sliding downward trend; (6) Talus tends to be stable.
Materials that composed of talus have large spatial variability on mechanical properties, it shows strong heterogeneity and anisotropy.

The transverse stresses σy, σz, τyz and other stresses away from the cutting plane will not affect the deformation on the boundary.
Two sets of tension-compression test data were recorded to examine the mechanical behaviour of the En8, one with the maximum loading strain of 0.026 and the other with the maximum strain approximate to 0.051.
Table 1 Measured Mechanical Properties of En8 (080M40) 0.2%Yield Stress (σ0) Elastic Modulus (E) Poisson's ratio (µ) Strain hardening exponent (n) Units MPa GPa Measured 450 195 0.295 6.5 The specimen containing the cold expanded hole was 100mm long, 40mm wide and 12mm thick, machined from a cold-drawn flat bar blank with cross section of 2" × 0.5" (49mm × 12.25mm).
However, efforts were made to minimize errors from each of these factors.
A multi-linear material model was used to represent the En8 mechanical behaviour in the FE analysis.

Actual mining process was studied through calculation with every step of 10m excavation, as open stope method was used for this mining, the support effect of artificial ore column was affected by designed strength construction process and other factors influences, roof-contacting was often not enough or pillar strength could not reach design requirements and resulted in movement and even collapse of goaf overlying rock stratum.
(b) AE distribution of overburden rock with mining 30m (a) Failure model of overburden rock (a) AE distribution of overburden rock with mining 20m (b) Schematic diagram of mechanical model Fig.1.
Failure and mechanical models diagram of overburden rock under mining layout Fig.2.
The microcracks of the gathered nucleation will greatly reduce the mechanical properties of rock material; with the increase of goaf and under the influences of tectonic stress, self-weight stress and external disturbances, macroscopic failure was produced in the so-called " tranquil period " of AE.

Even though SMA's have a lot of disadvantages, with the correct determination of properties a workable prototype should be able to be manufactured.
Aspects like electrical, thermal and mechanical behavior need to be designed simultaneously.
On the other side experimenting data can be invaluable due to the close relation with all the different factors.
Ashby, The selection of mechanical actuators based on performance indices.
Duerig, The Mechanical Aspects of Constrained Recovery, in Engineering aspects of Shape Memory Alloys, T.W.

EDM is best suited for machining high strength conductive materials since neither mechanical contact nor cutting is necessary [1].
When tools are miniaturized, the surface microstructure and material texture begin to affect the mechanical properties of the components; thus undesirably increasing the structural sensitivity.
Micro tools used for micro punching and micro cutting require sufficient mechanical strength to withstand the load during machining.
Yates algorithm for finding significant factors of the overcut of the produced holes Fig.4 Half normal probability plot for the overcut of the micro holes Regression analysis is also performed to find out the relationship between process variables and performance characteristics considered.

Dynamic Analysis and Structural Optimization for a Logging While Drilling Neutron Instrument Chao WEIa, Qiu-yue SUNb, Yuan-ying QIUc and Jun-jie YE* School of Electro-Mechanical Engineering, Xidian University, Xi’an 710071, China aweichao1927@163.com,bsunqiuyue900816@163.com, cyyqiu@mail.xidian.edu.cn, *ronkey6000@sina.com Keywords: Logging while drilling neutron instrument, Dynamic analysis, Topological form improvement, Structural parameter optimization Abstract.
The uniqueness of the function and structure form of the LWD neutron instrument studied in this paper leads to its particularity of the dynamic characteristics and influencing factors.
Due to structural complexity, the geometric model of the LWD neutron instrument is simplified as follows: deleting chamfering, holes and thread relief groove and simplifying the local components which compose of many small parts but have little influence on the mechanical properties of the whole model.
Therefore, it can be concluded that the modals of the x and y directions are easy to be inspired to cause the resonances and this will make the root-mean-square value of the acceleration response enlarge and then affect the precision of the instrument readings.
Li, Mechanical Vibration Theory, Zhejiang University, Hangzhou, 2005.

All these forces would affect the tensile, bending, and flexural strength of the boat structure and its hull in particular, and since bending is actually consists of tensile and compression therefore only tensile and flexural strength of the material are investigated in this research.
For safety reason the thickness is multiplied by 1.5 as safety factor, and therefore for the chosen boat the proposed thickness of the side hull will be 10 mm, and the bottom hull will be 18 mm.
In the case study application on a 28 m patrol boat the composite thickness efficiency of the VARTM method could reach as high as 45% compare to hand lay-up method, and this will also affect the production cost of the boatyard.
ASTM D3039-00, Standard Test Method For Tensile Properties Of Polymer Matrix Composite Materials.
[12]Wonderly Christopher et al. (2005)Comparison of mechanical properties of glass fiber/vinyl ester and carbon fiber/vinyl ester composites.

L length of the workpiece liquid mass fraction R Radius of the workpiece h convective heat transfer coefficient Greek Symbols sensible heat Δt time step size H total enthalpy ΔV control volume k thermal conductivity ΔH nodal latent heat laser peak intensity τ pulse width latent heat for fusion κ absorption coefficient ms millisecond α thermal diffusivity enthalpy source term λ under-relaxation factor
T temperature σ Stefan-Boltzmann constants t time σc temperature slope of surface tension Source term for laser r-momentum source term z-momentum source term Subscripts Superscripts S solid phase n number of iteration L liquid phase 0 previous time step m melting point Introduction Laser assisted manufacturing process has become popular in the manufacturing industry because of its better accuracy, precision, less heat affected
Laser energy, duty cycle, frequency, pulse width and beam radius and mechanical and optical properties of the processed material are the parameters that greatly influence the laser-material interaction during the machining process and subsequent surface finish.
Titanium alloy is the workpiece material and its thermo-physical properties are taken from literature [10].
Yilbas, Study of affecting Parameters in Laser Hole drilling of sheet metals, Journal of Engineering Materials and Technology. 109 (1987) 282-287

However, the material of the fabrication properties limits the conversion ratio of the thermoelectric modules [4].
The temperature variation rate is a critical factor in enhancing the electric response of pyroelectric devices while pyroelectric materials and geometry are determined.
The different heat transfers also affected the efficiency of the Olsen cycle.
Although a commercial PZT bulk material possesses excellent pyroelectric properties, a thick pyroelectric material with a high thermal capacity obstructed quick temperature variations.
Therefore, various patterns in pyroelectric sheets were greatly to affect the efficiency of pyroelectric harvesting converters.