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The modulus and tooth number of double-circular-arc gear are the main factors influencing the gear bearing capacity.
According to the formula (3) and (4) , the safety factor formula: ,.
For the checked safety factors, the factor of double-circular-arc gear contact strength is bigger than the one of its bending strength, so the bending stress need to be further analyzed.
Zhu: Electrical and Mechanical Product Development, Vol. 21 (2008) No.5, p. 55-57
Zhang: Mechanical Research and Application, Vol. 22 (2009) No.2, p.16-18

Comparsion of Machining Stability of Up and Down Milling Te-Ching Hsiao 1, a and J-J.Junz Wang 2,b 1 Department of Mechanical Engineering, National Cheng Kung University, Tainan, 70101, Taiwan R.O.C.
In this model, the elementary cutting function, which represents the trajectory of cutting force for a certain local cutting edge, plays an important role in affecting machining stability of the different cutting configurations.
As shown in Eq.(17), Pxx and Pyy are the important factors that affect the stability of the one-dimension milling system.
Pa and Pb are key factors affecting the stability of this symmetric two-dimension milling system.
In these analyses, the elementary cutting function plays an important role of affecting machining stability for different cutting configurations, and this function with positive and negative value will lead to totally different chatter features.

Introduction Ultra-fine grained materials offer significant advantages in terms of high strain rate superplasticity and improved mechanical properties, compared to materials with conventional grain sizes [1].
These factors have led to a significant commercial interest in severe deformation processing.
This effect has previously been used to obtain superplastic properties in conventionally rolled sheet materials [10].
Other fundamental material properties also have a significant effect on the formation of an ultrafine grain structure during severe deformation.
These factors will require further investigation before successful commercial processes can be developed.

The results show that the magnified effect of acceleration response spectrum of each layer present more outstanding under far-field ground motions than under Suzhou artificial waves, with the increasing of bedrock peak ground acceleration, there is probability that the peak of long-period component of acceleration response spectrum appears higher than that of the short-period within 15m depth, which may adversely affect the long-period building structures.
Table 1 Borehole data of soil layers under Suzhou rail transit line 3 No.of layer Property of soil CZ1 CZ5 CZ18 d [m] ρ [g/cm3] d [m] ρ [g/cm3] d [m] ρ [g/cm3] 1 Miscellaneous fill, variegated, loose 0.9 1.97 1.0 1.90 1.0 1.88 2-1 Silt clay, gray~sallow, plastic 1.4 1.91 - 2.5 1.94 2-2 Silt clay, gray, soft~moderate plastic - 4.5 1.93 - 3-1 Clay, brown yellow, moderate~hard plastic 4.8 1.94 - 4.5 1.85 3-2 Silt clay, gray yellow, moderate plastic 8.2 1.96 7.4 1.89 10.6 1.82 3-3 Silt, gray-gray yellow, loose~moderate density 14.0 1.99 11.9 1.87 - 4-1 Silt clay, gray, fluidal~soft moderate plastic 17.3 1.96 14.2 1.95 13.0 1.83 4-2 Fine sand mixed silt, gray, medium dense - 17.2 1.91 18.3 1.85 5-1 Silt clay, gray, fluidal~soft plastic - 33.8 1.93 23.3 1.85 5-1A Silt, gray, medium dense - - 26.0 1.83 5-1 Silt clay, gray, fluidal~soft plastic - - 32.0 1.85 6-1 Clay, gray yellow, medium~hard dense 21.6 1.96 - - 6-2 Silt clay, gray yellow~caesious, moderate plastic
The deep soft site have double effects of magnification and absorption on earthquake motion [10], absorption is thought to be one of the intrinsic qualities of soils while the magnification effect is related with some other factors such as site characteristics, soil layers and frequency spectrum of input ground motion.
To take section CZ1 for example, contrasting borehole data of CZ1 section in the Tab. 1, and we can discover that the character of soil horizon take large changes at layer number 6 and 8, which are in the range of sediment hard soil, as hard soil intertonguing with layer number 3-3, 4-1, 7-1, 7-3 and 7-4, weak plane of poor mechanical property were formed, finally the soil would have large shearing deformations under seismic motions.
With the increasing input bedrock peak acceleration, there is probability that the spectral peak of long-period component of acceleration response appear higher than that of the short-period within the 15m depth, which may adversely affect the long-period building structures.

Based on the properties of titanium alloy material and the external characteristics of the impeller blades, proposed control method for machining distortion of impeller blades.
High cutting temperatures will directly affect the quality of the cutting surface.
By changing the scale factor, find the distance between different points on the tool axis vector .
Then introducing proportional factor.
Journal of Mechanical Engineering. 2005,41(11):pp.134~139

In the latter, the TiB2-Al composite synthesis under a free fall MGE, for example, has made clear that the lack of mass migration and the improvement of wetting between TiB2 and Al under the MGE affect the formation of a fine and dense cermet-like structure in the products.
With this intermediate metal layer, the produced ceramic lined pipe has not only high strength and toughness of metals and high resistance against corrosion and abrasion of ceramics but also high resistance against thermal and mechanical shock.
The experimental date on mechanical properties of the produced long ceramic-lined pipe shows that the differences of these properties in the direction of pipe length are negligibly small within the present testing precision, except for the data near the pipe end.
The duration of produced ceramic and metal in molten phases would be an important factor.
Therefore, it is considered that heat and gas gravitational transportation affects the combustion propagation.

Part build orientation also affects the surface, i.e. built on the X, Y, or Z axis and has the biggest impact on part strength and surface aesthetics.
The second process that was evaluated was a mechanical mass finishing process.
Since this mechanical process does induce forces on the parts, it is not intended for very small or intricate parts.
For antenna and electronic applications, this is a limiting factor on both the size and complexity of geometries that can be built.
Further work is being done to optimize the FDM PC-ABS formulation to enhance mechanical part properties.

According to the geological and hydrological conditions, the size and shape of the cross-section, the length of the tunnel, the engineering support form, the buried depth, the construction technology and equipment, the project duration and other factors, underground construction projects have a variety of construction methods.
Shield construction has many characteristics such as high degree of automation, saving manpower, fast speed of construction, excavate at once, and not affected by climate, can control the ground settlement, reduce the impact on ground buildings, the underwater excavation does not affect the water transport, in the tunnel under the condition of long, large buried depth, shield in subway construction is more economic and reasonable.
At present, from the construction management and technical measures have some new progress, such as pre grouting and freezing of the soil reinforcement, can significantly improve the safety of excavation construction of Shield Crossing Rivers, As shown in Fig 4, the use of new technology of river diversion pile cofferdam construction is simple, detachable, material recycling, short time limit and no pollution to the river; As shown in Fig 5, new technology channel seepage “two Cloth one Membrane” is better than the reinforced concrete rigid flexible and economic structure seepage, with higher properties; stronger resistance to deformation, little affect the river ecological.
To this end, around quickly closed, low pollution, the respect such as mechanical operation appeared a lot of new type of special equipment.

These operations are often difficult due to composite mechanical and thermal properties: heterogeneity, anisotropy and low thermal conductivity [1,2].
The predominant factor influencing Sa-parameter is grits size.
Consequently, mechanical properties of the material are affected and chips removal becomes easier.
This value depends also on other factors such as material bulking.
Grit size and feed per revolution are also key factors to assure required surface roughness and improve productivity, respectively.

Design of Control System Based on PLC for Polycrystalline Silicon Decomposition Furnace Han Qiang and Luo Yuan-lin College of Mechanical Engineering Donghua University, Shanghai, China hanq@dhu.edu.cn, luoyuanlin600@163.com Keywords: PolycrystallineSilicon; DecompositionFurnace; PLC;Auto-tuning PID Abstract.
When siliane decomposition reaction happen, the furnce pressure and temperature control, not only affect product quaility, more important is directly impact on safty.
Frame of control system Auto-tuning PID control Schneider Twido PLC has the function of auto-turning PID, it is assumption that the temperature transfer function of target is In the funcion, K is proportional factor,K=(change of output)/(change of input); L is dead time;T is property of time; And , R is the slope of output.
LiLi, “Research and application of the temperature fuzzy-PID control system for thermo-mechanical simulator,” 2010 Chinese Control and Decision Conference, CCDC 2010, p3434-3438, 2010