Authors: Moon Kyu Lee, Jae Bong Choi, Kui Won Choi, H.N. Lim

Abstract: In the area of biomaterials, the structures with negative Poisson’s ratio are able to be
applied to the polymer component of prosthesis, artificial blood-vessel and catheter. To induce its
characteristic, previous studies postulated many structural shapes such as non-convex shape with reentrant
corners and re-entrant honeycomb. In this study, we proposed the rotational particle
structures and investigated the Poisson’s ratio and the ratio (Ee/E) of the elastic modulus of these
structures based on structural design variables using finite element method.
The auto-meshing preprocessor was coded using MATLAB in order to construct numerical
models as design variables and perform finite element analysis (FEA) effectively. Three selected
design variables were the ratio of fibril’s length to particle’s diameter (0.2~2.0), the ratio of fibril’s
length to its width (0.02~0.2) and the angle of fibril about horizontal axis (0 degree ~ tangential
angle). Finite element model has 2D plain stress quadratic element and composed of 515 particles
and 6-linked fibrils per each particle. For all of 213 cases, one side of each model is applied a
tension, 0.1% strain and analyze Poisson’s ratio and the ratio (Ee/E) of the elastic modulus.
As the ratio of fibril’s length to particle’s diameter increased and the ratio of fibril’s diameter to
fibril’s length decreased fixing the fibril’s angle with 45 degree, the negative Poisson effect of
rotational particle structures increased. The ratio of elastic modulus of these structures decreased
with Poisson’s ratio. The results show the reasonable values as compared with the previous
analytical results.

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Authors: Xiao Feng Zhuang, Qing Kai Zeng, Bing Ren, Zhen Hua Wang, Yue Lu Zhang, Li Ya Shen, Mei Bi, Jian Huang, Ke Tang, Ling Yun Shi, Yi Ben Xia, Lin Jun Wang

Abstract: In this paper, the threshold voltage of diamond film-based metal-semiconductor field effect transistors (MESFETs) has been simulated using Silvaco TCAD tools. The drain current (Id) versus gate voltage (Vg) relationship, and the distribution of acceptors in diamond surface conduction layer were also investigated. From the simulation results, it was found that the gate length contributed the most to the threshold voltage, while the doping depth almost had no impact on the threshold voltage value.

1093

Authors: Zhuo Zhang, Jian Ping Gao

Abstract: Flow path on the highway is longer, driving exits the more dangerous. Based on the mechanical theory, the calculation models of the flow path length in different sections were built by FDM and multiple linear regression method. The flow path length of different section and different longitudinal slope was studied. The results show that: in addition to straight line and circle curve, when the number of lane is more than 4 and longitudinal slope is greater than 4%, the flow path length at other sections almost exceeded the prescribed value. Made the flow path length as control index, the amendment value on the maximum longitudinal slope of highway is proposed.

1672

Authors: Hai Jun Zhao, Hai Xia Wang, Jia Dong Chang, Qi Li, Li Ping Tian

Abstract: Using orthogonal experimental design method structure parameters of work piece for muffler element with inserted tube are determined. Flow noise regeneration of them is measured on the self development test bench. Relationship model on total sound power of flow regeneration noise and structure parameter and flow velocity is established utilizing Multiple linear regression method, model parameters are solved making use of hyper static least square method. Significance test of the model is performed, the law of total sound power level for muffler element flow regeneration noise changing with the parameters is discussed. Result shows that the established models is all highly significant under 0.01 levels, and inserted length of outlet tube and inn-diameter of inlet tube have higher effect on the flow generation noise, and decreasing the inserted length and the inn-diameter are in favor of reducing flow generation noise. But inserted length of inlet tube and expansion ratio have little effect on the flow generation noise.

1149

Authors: En Dong Wang, Yan Yin, Qing Du

Abstract: Shear-thinning power-law fluid is a kind of non-Newtonian fluid in which the viscosity is a function of shear rate. Impinging jets system is used to study the breakup characteristics of power-law liquid sheets formed by two symmetrical round jets in this study. High quality images are obtained from the experiment with a high speed camera and breakup length is extracted from the images. Closed-rim sheet, web-like sheet and ligaments sheet are observed with the increase of jet velocity. A series of images show that the wave length on the surface of sheets tends to decline as the jet velocity increases. At a low We number, the breakup length increases with an increasing We number. However, it first increases and then decreases when the liquid sheet breaks up at a high We number. The liquid jets with larger diameter collide to each other and lead to a liquid sheet with a smaller breakup length.

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