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Fig. 1 Combustion chamber mesh Influencing factors and laws of NOx emission (a) (b) (c) Fig. 2 The curves of cylinder pressure, temperature and NOx emission of different influencing factors There are many factors affect NOx generation in the combustion process of diesel engines.In this paper,the main (emphasis is placed on the influence of )five factors including intake temperature, load, fuel injection advance angle, engine speed and intake lag angle.
Fig. 2(c) shows the comparison of NOx emissions when different influence factors change.
The NOx emissions value calculated when five factors changes are shown in Table 3.
Whereas Fig. 3(b) shows that the maximum temperature in cylinder is 165 K, lower than that of diesel engine, due to DME’s physicochemical properties, the combustion temperatures on average in cylinder decrease.
Experimental Research on Influencing Factors of NOx Emission for Diesel Engine.

In order to determine the optimum joint conditions, four key process parameters affecting the joint quality of laser transmission joint of 1mm thick PET film and PC film，namely，laser power, scanning speed, clamping pressure and scanning number are optimized by response surface methodology in this paper.
Laser transmission joining for dissimilar materials with many outstanding advantages, such as high precision , biocompatibility property, low distortion to the substrate materials and minimal heat-affected zone is emerging as a major joining process, especially in present years[5,6,7,8,9].
But the most common problem is that only a few reports express the optimization of joint parameters in terms of process input factors in order to determine the optimal joint conditions.
Experimental design The experiment based on response surface methodology (RSM) with four factors at five levels each was applied to find out the optimum levels.
The following independently key process parameters affecting joint quality are identified to carry out the experiments: laser power(P), scanning speed (S), clamp pressure (F) and scanning number(N).

Physical and mechanical properties of the gypsum cement pozzolan composite.
Physical and mechanical properties of the gypsum cement pozzolan composite.
Physical and mechanical properties of the gypsum cement pozzolan composite.
Physical and mechanical properties of the gypsum cement pozzolan composite.
The quantity of these values obtained as a result of the preliminary experiments are taken for the main levels factors.

Compared with inorganic materials, conjugated organic materials are more predominant in properties such as large nonlinear optical susceptibility, fast response, high resistance to laser radiations, low dielectric constant, and ease of processing.
The solution was kept at 0℃ for 1h with vigorous mechanical agitation.
The thermo-optic property of HEPU.
Thermo-optic coefficient (dn/dT) is the variation of refractive index depended on the temperature and is the main factors to affect the driver power and response speed of the optical switch.
Transmission loss of optical waveguide devices is produced mainly by the following factors: waveguide material loss caused by scattering and absorption; substrate surface finish by polishing process constraints, irregular interface leading coupling loss between guided mode and radiation mode; curved waveguide surface, causing the loss caused by energy radiation.

Finite element analysis of bicycle saddle based on ergonomics Ying Xin1, a, Xiuping Yang 2,b and Lei Zhang3,c 1Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems,Tianjin University of Technology Tianjin 300384,China 2School of Mechanical Engineering,Tianjin University of Technology Tianjin 300384,China 3School of Fine Arts,Tianjin University of Technology Tianjin 300384,China axinying913@163.com, byhp420@sina.com, czhanglei_885@sina.com Keywords: Finite element method, Man-machine engineering, Bicycle-saddle.
Seating comfort is an important factor for bicycle-rider.
It was shown that riding on discomfort saddle could affect the blood circulation system, genitourinary system of human, and harm to their health.
The main purpose of the present work is to introduce a fairly detailed finite- element model for a seated human and for a generic bicycle saddle to carry out a preliminary computational finite element analysis of the seated-human/saddle interactions in order to help identify the factors which affect seating comfort/discomfort.
Table 1 Inertial parameters of human body's rigid link Fig.1 Multi-rigid body Fig.2 Finite element model Finite element analysis of seated human/saddle Igs file was imported into the finite element analysis software, ansys, then the relevant material properties of human body and the saddle were given.

In the production of net-shape parts, the challenge is a constant process behavior and product quality, even if the properties of the semi-finished parts are affected by uncertainty.
When using single stroke bulk metal forming processes like closed-die forging, the geometric properties of the product are strongly depending on the volume of the blank.
Apart from the influence factors described by [3, 4] the aim is to examine if the movement pattern has an influence as well.
The influencing factors are the infeed per revolution, the inclination angle and the movement pattern.
In terms of control theory, adjusting just one system variable without affecting the other is called decoupling.

When we established the model, according to the structure and the work characteristics of the universal joint, maintaining its mechanical properties, The components which are not involved in power transmission and details of solid form which influence on contact situation lightly are ignored.
According to the material properties of the joint, in the Engineering Data module of ANSYS Workbench, define the universal joint material property, set as shown in table 1.
In order to facilitate research, on the premise of ensuring not to affect the analysis of structure, assume that the input shaft is the axis of the cylindrical shell, and the output shaft is the three pivots.
The fatigue life simulation analysis According to the selected materials, refering to the mechanical engineering material performance data handbook, enter the material S-N curve, and input the scaling factor of constant amplitude alternating stress load.
Accordingly, the safety factor of the needles, three pivots and spherical rings is relatively low when universal joint is under variable load conditions.

The large deformation Rigid-visco-plastic FEM program DEFORM-2DTM is used, and thermo-mechanical coupling effect are considered.
But, these models could not really account for many factors, for example, flow stress varying strain, strain rate and temperature, fracture, serrated chip and residual stress.
For the temperature calculations, the thermal properties of workpiece and tool are provided.
It is an important factor influencing cutting force.
Palmer and P.L.B Oxley: Proceedings of International Mechanical Engineers Vol. 173 (1959), p. 623 [5] E.

Large variety of factors, often with random nature, affecting the output parameters of the modeling object do not allow the deterministic approach’s use for its behavior analysis [4].
Taking into account the whole variety of known probabilistic laws, the effect of exponential growth of the probability of an event occurring with an increase in quantitative parameters affecting it comes first.
A typical example of this provision validity is the exponential dependence of the probability of a dangerous defect exist in the analyzed volume of a structural material on its value - the so-called scale factor (SF) of strength [1, 4].
Mechanical engineering: technologies, equipment, personnel
Int J Fatigue 82:540–549 [25] Yuri T, Ono Y, Ogata T (2003) Effects of surface roughness and notch on fatigue properties for Ti-5Al-2.5Sn ELI alloy at cryogenic temperatures.

Factors Affecting the Viscosity of Asphalt Grouting Asphalt grouting used in stone revetments is grouting made of bitumen, stone powder, sand, and gravel (can be added), at high temperatures with high fluidity, can fill itself into hollow slots between stones.
In addition, other physical and mechanical properties of aggregates such as solidity, aggregate origin also have significant impact on bitumen consumption, viscosity of composite materials [4, 5]
The optimal bitumen content depends on the type of bitumen, the proportion of ingredients, mechanical properties of loose materials (stone powder, sand, and gravel) and needs to be tested to determine [4, 5, 10]
As mentioned above, the physical and mechanical properties of the materials constituting the composite material have a direct effect on the viscosity of the mixture.
The influencing factors, the variability of the influencing factors (according to domestic and foreign experience), experimental scenarios are identified and experiments are conducted according to scripts.