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Brittle materials are popularly used as engineering materials for excellent properties.
It could be found that the material properties led to the different surface characteristics of brittle materials.
By the comparisons of surface topographies during the grinding process and the surface roughness after precision grinding between different materials, the mechanism of surface formation for different brittle material were discussed with relation to their mechanical properties.
Moreover, for the ceramic is sintered body, its mechanical properties are better than the other brittle materials.
The surface characteristic of silicified marble was affected by the natural pores.

A cylindrical PMLSM has no crosswise breaking so its magnetic field evenly distributes along the axial direction, but the starting thrust was easily affected by voltage fluctuation.
Fig. 2 Meshing process of the radially magnetized cylindrical PMLSM The permanent magnets (PMs) of a PMLSM are the excitation source and can be set by the coercivity in the PM material properties.
Mechanical & Electrical Engineering Vol. 27 (2) (2010), p. 86, In Chinese
Mechanical & Electrical Engineering Vol. 21 (11) (2004), p. 35, In Chinese
Ye: Technology Manual of Linear Motor (Mechanical Engineering Press, Beijing, China 2003), in Chinese.

It was found that both these factors were dependent on the diameter of the electrode.
Material Properties.
The thermal and mechanical property of copper material is listed in table 5.
The model is created by giving proper thermo-mechanical properties of the copper.
It was found that Pulse on time and Pulse off time were the most significant factors affecting the response parameters.

Introduction With the development of mining subsidence research, the basic understanding was generally acknowledged by scholars at home and abroad that the geological and mining factors were the two main factors affecting the development of mining subsidence [1-4].
Currently more research results were made on the influence of various mining factors [5-6], and fewer research results were made on the influence of geologic factors in the development of mining subsidence [7].
Weathered layer is not considered in the frame structure because of its complex properties, and covering stratified structure framework is designed as: "sand bed-soil-bedrock layer-2-2coal bed- baseboard".
The setting of the physical and mechanical parameters.
The physical and mechanical parameters of coal seam and rock and soil layer in the model are assigned based on Table 3.

However, in actual operation, due to technology, working conditions, design and many other factors, may cause abnormal vibration of automatically benchmarked devices.
Modal is a natural vibration characteristics of the mechanical structure, each mode has a specific natural frequency, damping ratio and mode shapes.
Also, according to ω = 2πf can be obtained for each order natural frequency of the system that modal frequencies, mode shapes that modal shape. 4.MODAL ANALYSIS The steps of modal analysis have: modeling, setting the material properties, the definition of the boundary conditions, meshing, solving, view the results, the process shown in Figure 2.
Its material properties are shown in Table 1.
Material properties Description Modulus of elasticity/Gpa Poisson ratio Density/ 45 200 0.3 7.85 Meshing has a direct impact on the whole calculation results.

On the down-side, it can affect dimensional accuracy by causing subsurface damage and introducing residual stresses.
As regards the structure of the part to be machined, the relationship between processing, structure, properties and behavior of a material is extremely important because it is known that this structure, which depends on how it is processed, exerts a high influence on the properties of the obtained products and their performance depends directly on these properties [9].
Thus, castings have mechanical properties that depend on aspects of its structure, such as grain size, dendritic, lamellar or fibrous spacing, and defects such as heterogeneities in the chemical composition, size and shape of inclusions, porosity, which in turn is a function of the conditions of solidification and, therefore, affect its mechanical properties [9].
With the increasing demands of modern industry for materials with enhanced properties and better ease of mechanical forming, controlling the kinetics of the solidification process of metals and alloys comes every day consolidating itself as an object of study of extreme importance to obtain materials with homogeneous properties and increasingly suitable for practical use.
On this way, considerable research [10-19] have been made ​​in recent decades in order to establish in a systematic way the influence of various operating parameters and thermal phenomena involved in the solidification on the resulting structure, seeking to raise the mechanical properties and therefore, the performance of the materials solidified by experimental procedures which were implemented in the vast majority of directional vertical upward and downward solidification systems.

Our investigations also concluded that other environmental factors can also play a secondary contribution in limiting service life of the refractory lining in the superstructure, particularly in the upper wall region.
The upper walls are subject to mechanical abrasion during cleaning operations, so some degree of abrasion resistance is necessary in the refractory lining to cope with the mechanical stress endured during cleaning.
This knowledge of the strengths and weaknesses of the existing material technologies was then used as the basis for a series of reformulations to find the optimum balance of bond and aggregate chemistry and product granulometry that produced the maximum improvement in alkali and thermal shock performance without negatively affecting other important properties.
Table 1: Physical properties of materials studied.
By working closely with aluminium producers, the main factors limiting furnace lining performance in the Superstructure (inc. upper walls, roof and flue) of Al melt-hold furnaces have been identified as severe alkali attack and thermal shock, with abrasion and aluminium alloy reactions identified as secondary factors in the upper walls. 2.

More recent applications tend to develop MMC in order to improve tensile and fatigue properties and to lighten the material.
The final properties are dependent on the amount, size and distribution of the TiC particles, as well as on the steel matrix microstructure obtained after processing and treatments.
The TiC particle size was determined by Rietveld refinement and estimated to 25 nm after mechanical alloying.
The last factor that may affect the transformation kinetics is the changes in nucleation sites.
We can expect that the main factors that affect the kinetics of ferrite formation are on one side the local composition of the austenite at the TiC/austenite interface that depends on the interactions between the TiC and the matrix during the complete treatment, as well as the increase in nucleation sites.

It is aimed to test structural performance of old beams, to see if different structural use affects the performance and deformation of the wooden elements.
At first glance, it is seen that selected wooden pieces have been affected by mostly moisture; especially the ones have connection with masonry parts of the building.
Properties of Beam Elements Sample Name Original Dimensions in section (b*h mm) Approximate Specimen dimensions (b*h*l cm) Use in Structural System Deterioration type B01 160*160 A(5*5*20) Old Main (supporting) beam color change, some holes but they effects only the surface B (5*5*20) C (5*5*20) B05 75*135 A(5*5*20) New Secondary beam - B(5*5*20) Table 7.
References [1] EN 384:2004 Structural timber-Determination of characteristic values of mechanical properties and density [2] EN 408:2003 Timber structures - Structural timber and glued laminated timber - Determination of some physical and mechanical properties [3] M.
Karaman, Wooden Load Bearing Structural Elements of Kula Traditional Houses Case Study of Zabunlar and Goldeliler Houses, in J.Grill (Ed.), Proceedings of the International Conference on Wood Science for Preservation of Cultural Heritage: Mechanical and Biological Factors held by Cost Action IE0601, November 5-7, Braga, 2008 (2010), pp.316-322.

The intensity of reflected radiation depends on the optical surface properties of the encountered material.
On this fact is based the possibility of identification of certain components of the mixture, if the optical properties are considerably different from other components.
The limit of demarcation between reflectance of coal and different types of sterile is influenced by disturbing factors that occur at the plant operating detection under practical conditions such as: material humidity, the variability level of the material on the conveyor belt, the existence of a light background ambient.
The intensity of the reflected radiation depends on the optical properties of surface of the met environment.
On this fact lies the possibility to identify the presence of certain components in a composition if optical properties sensibly differ from other components, [2].