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Numerical Simulation Research of Precision Injection Molding Control Method Based on P-V-T Properties of Polymers XIE Peng Cheng1,a, GUO Xiao Long1,b, GOU Gang1,c, DING Yu Mei1,d, ZHANG You Chen1,e, YANG Wei Min1,2,f 1College of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China 2State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China axiepengcheng@gmail.com, bxiaolonggd@gmail.com,cgougang1986@gmail.com, ddingym268@gmail.com, ezhangyc@mail.buct.edu.cn, fyangwm@mail.buct.edu.cn Keyword: Precision injection molding; P-V-T; P-T control method.
P-V-T (Pressure-Specific-volume-Temperature) properties are inherent characteristics of polymers.
Introduction Injection molding as a complex forming process, a variety of factors affect the quality of the molded parts, such as weight, orientation and shrinkage.
The constant specific-volume control was regarded as an ideal packing control based on P-V-T properties of polymers before the gate frozen up and then drops to atmosphere.
References [1] Jian Wang, Pengcheng Xie, Yumei Ding, Weimin Yang, On-line testing equipment of P-V-T properties of polymers based on an injection molding machine.

This process is included in the group of indirect additive techniques, that is, the properties of the part that comes out from the printing stage (green part) is far from the final properties, hence post-processing is required.
After debinding, the part is highly porous and weak, thus, the mechanical properties are poor
Other parameters can also influence the final properties, such as part orientation, which generates the stair effect and therefore affects the surface quality; also, the exposure time between two consecutive layers, which affects the mechanical, physical and microstructural properties of the printed parts [9].
The geometry, symmetry or thickness of the part are factors that influence the curling effect.
Chartier, Numerical prediction of elastic properties for alumina green parts printed by stereolithography process, J.

Properties such as straightness, dimensional stability, unlimited length and interchangeability with unjointed timber make it suitable for the above cited applications.
Several timber-related factors are also known to affect the strength of finger-joints, such as species, density, and natural defects, while others are related to the gluing process.
In order to better understand the mechanical behaviour of timber beams in bending, a non-linear numerical analysis is necessary.
The material properties for Spruce wood are: E1 = 12.7GPa; E2=E3=0.43GPa; n12=n13=0.39; n23 = 0.51; G12=G13=0.73 GPa; G23 = 0.03 GPa; syield = 55 MPa; Q = 0.75 GPa; b=17; F= 0.35; G = 0.4; H = 0.6; L = 1.5; M = 1.5; N = 1.45.
Cohesive zone models (CZM’s) were used to simulate these fractures, whose properties were estimated from literature data.

Jiang et al.[3] set up a one-dimensional multi-layer model with burn damage, which showed that the thick of epidermis and dermis affect the temperature and burn injury. 2004, Y.
Finally, find out the factors that influent the effectiveness of freezing, and provide a reference for the follow-up work.
The thermal physical properties of the pork tissue are showed in table 1[12].
Meanwhile, there is phase change in the process of liquid nitrogen freezing the pork tissue, and the thermal physical properties of biological tissue and the state of it are related [13], so we should consider the change of the thermal physical properties in simulation.
Since there are not clearly thermal physical properties of the pork tissue, we use the thermal physical properties of soft tissue, refer to the thermal physical properties in the literature [13].

Compared with the theoretical analysis, meshing feature and strength properties of the WN gear driving are gained.
In addition, taking into account the impact of factors of the fact manufacturing error and installation error in the design, in order to avoid the contact of the sharp tooth area, the curvature radius of tooth concave surface is larger than the one of convex surface with the meshing of gear tooth.
In this study, in order to study the tooth - contact vice -slave tooth of gear drive, taking the convex and concave arc tooth surface as contact model for three-dimensional geometry, for combined impact of a variety of factors in meshing, live meshing simulation and contact strength is analyzed under the load engagement of WN gear.
[2] Wang Wei, Luo Shanming, Chen Lifeng: Mechanical design and manufacturing, 2009, (2):72-73
[5] HE Song, GUNDA Rajendra: ASME Journal of Mechanical Design, 2007, 129(1):1064-1075

But there are two main factors (difficulties in processing and monitoring the integrity of materials [1]) preventing them from achieving further development.
First of all, since OF material properties are similar to reinforcing fibers of composite materials, they can be easily embedded in arbitrary shapes.
Thus embedded OF will alter the stress and strain in the vicinity of the embedded OF, destroy the materials’ integrality and continuity in some way, and even may degrade mechanical properties of composite materials [3,4].
Lee et al [2] evaluated the effects of embedded OF (φ125μm) on the tensile properties of unidirectional and cross-ply E glass-exposy system, and their results also showed no significant difference in the tensile strength.
This can be attributed to manufacturing variations. 2) Only when 3 OF are embedded in the bending sample, it has abou18% reduction. 3) Different embedded layers have different influence (Sample S3-2/3 affected most).

One of the key factors in the development of high-performance ESC systems lies on the properties of its active electrode material and the electrolyte.
These promising properties of ILs can be linked back to their unique structures that are formed by weak interactions of large cations and charge-delocalized anions [1, 8].
To address these challenges, intensive exploration on the selection of IL composition and properties has been carried out in various literatures [14-16].
Another effort in enhancing the mechanical and electrochemical properties of IL-based electrolytes was demonstrated by tethering ILs to titania nanoparticles to produce a solid electrolyte.
Surface tension is a physical phenomenon brought about by the cohesive forces between liquid molecules and is considered as one of the important properties that may affect the electrochemical performance of an electrolyte system.

China aLevinzhwen@126.com,bhoujunxing@126.com,cnewroom@126.com Keywords: Health management; Hybrid Systems; Mechanical Electrical and Hydraulic Integration(MEHI) systems; Fault diagnosis and Prognosis.
The degradation process of Mechanical Electrical and Hydraulic Integration(MEHI)systems have the characteristics of the hybrid system.
The physical properties of the system are expressed through the model and the changes of the parameters in the model are directly related to some certain physical states.
The systems involve many factors which are mutually related and restricted, and it is necessary to know whether there is a connection between the factors in order to establish a structural model of the system.
System modeling is the most crucial step in the diagnosis process and the quality of the model directly affects the diagnosis conclusion is right or not.

All these superior electrical properties are attributed to the CS powder, which makes more uniform do- pant distribution throughout the multilayer ZnO varistors.
The uniformity in the distribution of additives is an important factor to influence the figures of merit of ZnO varistors.
Electrical properties.
It is well known that physical properties of ZnO varistor materials depend strongly on the microstructure, including grain size and boundary characteristics.
The chemical homogeneity of specific dopants and the ceramic micro- structure play an important role in the electrical properties of varistors.

Therefore, the absorber material should have good mechanical properties and oxidation resistance at a high temperature; what’s more, high specific surface area must include to guarantee enough areas for thermal exchange [3~8].
So, the composite which is synthesized by the silicon carbide and andalusite will obviously endow the composite with good mechanical performance, thermal shock resistance, refractoriness and other properties.
This approach of these composites has the advantages of good thermal performance and mechanical properties.
Formula composition, firing system and microstructure are the main factors that affect the refractoriness.
The proportion of differential particles of SiC affects the properties of fired samples.