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Introduction Hydraulic manifold block has been widely used in the hydraulic system, which shall directly affect the design efficiency, quality and cost of the whole system.
When all the wire meshes are completed, connect genetic factors of each network, which forms the gene representation in the net (chromosome encoding).
penalty function (11) fitness function (12) In the formulas, , are respectively the value of inequality constraint and ; and are respectively the total length of the path and the value of the sum of auxiliary hole , is the penalty factor.
The mutation operation is to imitate the phenomenon of gene mutations in the evolution of organism, thus the chromosome structures and object properties are changed.
References [1].Mingqiang Li and Jisong Kou: The Fundamental Theory and Applications of Genetic Algorithms (Science Press, china 2002) (In Chinese) [2] Tao Li and Yu Luo: Journal of Southwest University of Science and Technology.Vol.19 (2004),P. 27 (In Chinese) [3] Zhankui Wang and Xiqu Chen: Journal of Engineering Design.Vol.15 (2008), p.66 (In Chinese) [4] Wanhui Liu, Shujun Tian, Chunqiang Jia and Yuning Cao: China Mechanical Engineering.

Sanding in well/reservoir is considered a life-cycle problem, which changes with time due to constraints imposed by operational factors of exploration, drilling, production and stimulation.
In summary, the following factors were identified as being critical to sanding (Fig. 1): • Pressure depletion • High fluid flow rates • Onset of water cut • Abrupt shut in and re-opening 3.
Many effective medium models relate the elastic properties of rocks to porosity over the range of porosities from 0 to 100%, and should be modified to recognize the critical porosity divider.
Operational data such as reservoir depletion, drawdown and fluid properties are also required to evaluate the tendency of a completion to produce sand.
R., 1970, : Method for Determining Permeability from Reservoir Rock Properties, Trans.

So the fire system in high-rise building is the key measures to protect the establishment of people's personal and property safety.
The detector should be selected according to the initial form, development characteristics, and the fire room height, environmental conditions cause reasons for false positives and other factors to decide in the detection region.
Fire electrical line laying mode and points for attention Laying electrical lines of building fire protection is first step in fire and electrical systems of buildings when installing the first link, Factors and electric circuit is the most vulnerable to the formation of the building fire hazards.
In practical engineering, in order to not affect the appearance of the building, concealed form generally is use during line laying.
Because of the fire pump, smoke exhaust fan, fire elevator and fire control center equipment is important for the fire safety of high-rise building, the project shall use good electrical properties, physical properties, mechanical properties and fire resistance of mineral insulated cable.

The authors studied a lot of 31 adult patients with haemophilia, with multiple joints affected by arthropathy.
Recent in vivo studies, on human and animal models, indicate that the tendinal tissue has elastic properties, with important implications on the interaction between tendon and muscle during locomotion.[16, 17, 18] Studies on animal model proved that the stretching of the tendon and the following recoil during relaxation may provide enough elastic energy, reducing the energy costs of locomotion.
The children with haemophilia often experience imobilization periods or periods of partial support (after acute haematrhrosis), periods that can decondition the tendons of the lower limbs, modifying their mechanical properties concerning their ability to store and release elastic energy, disturbing the mechanism of reducing the energy costs of gait.
Studies investigating te mechanical properties of the tendons and their relation with imobilization, with joint damage and with the physical performance are still required.
Mechanical energy fluctuation during walking of healthy and ACL reconstructed subjects.

The lime saturation factor (KH), silica ratio (SM) and aluminum ratio (AM) of the raw material have a major impact on the quality of clinker, Table 1 shows the main chemical components of raw materials and ingredients values.
Leaching properties of clinkers: The leachabilities of critical minor elements present in the clinkers were determined using the Solid Waste-Extraction Procedure for Leaching Toxicity (HJ/T299-2007) [8].
The vaporization of Cd was greatly affected by the low melting and boiling points of Cd and its chloride compound.
Fig.5 XRD patterns of cement clinker prepared from the raw meal with the addition of CdO (1: C3S; 2: C2S) Fig.6 Leaching characteristics of clinker after adding CdO into raw materials compared with that CdO was not added (μg/L) Leaching properties of clinkers.
Furthermore, the leaching potential of heavy metals under different environmental conditions is another important factor.

Densification Mechanism of Warm Compaction for Iron-based Powder Materials Shengguan Qua , Yuanyuan Lib, Wei Xia c and Weiping Chend College of Mechanical Engineering, South China University of Technology, Guangzhou 510640, P.
Densification of warm compaction is affected by many factors, and current research about warm compaction generally limits in powders formula, lubricants types and lubrication patterns of die wall [3,4].
Water atomized iron powder was selected as object of study because iron-based materials have extensive application potential, Chemical composition, particle size and properties of which are shown in Table 1. 98.7wt.% iron power and 0.6wt.% colloid graphite were dry blended with 0.7wt.% lubricant EBS, polytetrafluoroethylene, stearic acid barium and zinc, respectively.
Table 1 Chemical composition and properties of water atomized iron powder Chemical composition [%] Tap density Apparent density Flowability Particle size distribution [%, in volume] Fe C O [g·cm¯³] [g·cm¯³] [s ·(50g)¯¹] <45µm 45~76µm 76~125µm >125µm Balance ≤0.035 ≤0.15 3.8 2.98 26.7 21.3 28.0 48.0 2.7 5 13 14 15 16 17 18 19 1 2 3 6 7 8 9 10 11 12 4 Fig. 1 Experimental apparatus for measuring forces in powder compaction process 1-Steel ball; 2-Carrier rod; 3-External die bolster; 4-Upper sensor; 5-Inside die; 6-Upper punch; 7-Binding bolt M16; 8-Compression block; 9-Heater plate; 10-Powder; 11-Lower punch; 12-Lower sensor; 13-Cushion block of die plate; 14-Die plate; 15-Binding bolt M20; 16-Bolt M16; 17-Support plate; 18-Side force sensor; 19-Shore.

The difference in cationic field strength of individual rare-earth might result in different grain boundary phase properties and microstructure [6,7].
The samples were hot pressed at 1850 °C/1h (SiC) or at 1750 °C/2h (Si3N4) under mechanical pressure of 30 MPa in Ar+N2 (SiC) or N2 (Si3N4) atmosphere, respectively.
The formation of SiC-AlN solid solution affects the properties of sintered SiC, namely decreases the macro-hardness [16].
The reason for lower macro-hardness is the influence of several factors like triple pockets, porosity, grain size, indentation size effect, etc., but mainly the grain boundary phase composition in polycrystalline materials.

As a wide band gap semiconducting material, silicon carbide (SiC) exhibits many excellent properties for high temperature, high frequency and high power applications [3].
And SiC 1D nanostructures have shown many outstanding performances except for excellent mechanical properties.
These defects easily get affect by temperature variations or fluctuations.
The important factor here is the temperature, which controls the evaporation and condensation of the SiO gas through its small fluctuations due to Ar gas flowing effect.
The key factor is the use of carbon and varying substrate locations.

Design and Optimization of Runner and Gating System for Magnesium Piston Casting through Numerical Simulation Kangpei Zhao1, a, Jinhong Li 2,b and Qianghan Fang1,c 1Department of Mechanical Engineering, Shandong Jiaotong University, Jinan,250023, China 2College of Science, Shandong Polytechnic University, Jinan, Shandong, 250353, China akpzhao@sdjtu.edu.cn, blijinhong77@126.com, c sdjtufqh@126.com Keywords: Numerical Simulation; Gating system; Die casting die; Magnesium alloy Abstract.
Introduction As the lightest engineering material, magnesium alloys have the characteristics of high specific strength, heat conductivity, elastic modular, liquidity, resisting shielding property and electromagnetic interference.
This series of excellent properties make it widely used in automobile, aerospace, electron and communication.
Another key factor of magnesium die casting process is the filling time, which depends on wall thickness, flow distance and die temperature.
This turbulent flow filling pattern may easily lead to gas hole in die casting, which will affect the final quality.

Mechanical and tribological interactions between the billet and the extrusion tooling (stem, container and die) result in complex compressive and shear stresses in the billet.
Any inhomogeneity in extrudate temperature at the die exit within each extrusion cycle and between extrusion cycles may lead to undesirable variations in the shape, dimensions, microstructure and mechanical properties of the extruded product.
A constant friction factor of 1 was assumed at the workpiece/tooling interfaces.
The lower temperature inhomogeneity on the cross section of the profile leads to more homogeneous microstructures and mechanical properties of the extruded product.
These clearly present additional advantages as far as extrusion die performance and lifespan are concerned and should be taken into consideration in tool steel selection for extrusion dies, die heat treatment and surface treatment, all of which affects hot strength, hardness, fatigue resistance, wear resistance and in turn die costs, die performance and die life.