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Among many factors that influence the reliability of a flip-chip assembly using NCF interconnections, the most effective parameters are often the coefficient of thermal expansion (CTE), the modulus (E), and the glass transition temperatures (Tg).
Of these factors, the effect of Tg on thermal deformation and device reliability is significant; however, it has not been shown clearly what effect Tg has on the reliability of NCF.
The material properties of a NCF between the chip and a PCB have enormous effects on thermal fatigue.
Of these factors, the effect of Tg on thermal deformation and device reliability is significant; however, it has not been shown clearly what effect Tg has on the reliability of NCF.
This delamination is mainly affected by the shear strain at the edge of the chip.

This phenomenon which is defined as elastic recovery during unloading is one of the most important factors to influence the quality of sheet metal forming.
Spring-back could be affected by numerous factors during the process, including sheet thickness, tooling geometry, process parameters, lubrication conditions and material properties.
This assumption means that the material properties do not vary in different directions or orientations.
The aforesaid punch displacement should be precisely controlled in order to prevent the punch from penetrating the workpiece and also affecting the spring-back calculations.
[4] Tekiner: An experimental study on the examination of springback of sheet metals with several thicknesses & properties in bending dies, J. of Mater.

In this paper, we have engaged in the preliminary study on the production process and physical-mechanical properties of structural-building bamboo plywood, looking forward to provide a reference value and theoretical basis for its application in the construction field.
In order to prevent hot pressing thickness rebound after inflation, which affect the quality and machining efficiency sheet, the designed bamboo curtain's soak glue content is 7% ~ 8%, using the way of natural dry.
Results and Discussions In the same condition of MC and RC ,we can take orthogonal experiment with three factors and three levels of the pressing time, pressing temperature and sheet density ,and consider that the impact of the hot pressing process on the performance of bamboo plywood.
Conclusions (1) It can be seen that under different process conditions, the mechanical properties of bamboo plywood is substantially meet the “JG-T3026-1995 bamboo plywood templates”, more than the OSB/4 plate performance requirements and EN300-2006 requirements from the experimental results.
References [1] Zehui Jiang, Liang Chang, Zheng Wang: Physical and Mechanical Properties of Glued Structural Laminated Bamboo (CHINA WOOD INDUSTRY, China 2005) [2] Jian Han: Study on Relationship between Water Content of Thin Bamboo strips and Plybamboo Production Process (CHINA WOOD INDUSTRY, China 1998) [3] Jinming Chen.

Detecting DNA Using a Single Graphene Pore by Molecular Dynamics Simulations Wei Si1, Jingjie Sha2, Lei Liu , Jiapeng Li , Xiaolong Wei ,Yunfei Chen3 Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 210096, People’s Republic of China 1southeast_siwei@sina.com, 2major212@seu.edu.cn, 3yunfeichen@seu.edu.cn Keywords: dsDNA; graphene; MD simulation; gromacs; block current; translocating time Abstract：DNA charged negatively could be transported through a solid nanopore by the force of an electrical field.
Recently, the nice properties of graphene attract a lot of researchers.
For multiple graphene membranes, the factors affect DNA translocating time may occur, so we can’t just use the Van der Waals force as the dominating reason.
The main factors affecting DNA transport were the electrical field and diameter of pore, which can control the velocity of DNA.

initial 3.1.2 Nodes are connected detail size If you do not consider the material factors, the node connection detail size is mainly determined by the width and thickness of the strengthening ring.
Reinforcement ring for the outer limit of the two weldments thickness difference due to welding, makes reinforcement ring thickness generally taken closest to the beam flange thickness of the plate thickness, and therefore does not consider the reinforcement ring thickness factors to consider strengthening the ring width node rigid .
Similarly, in order to strengthen links with the outside point to strengthen the links point not consider strengthening the ring thickness factor nodes rigid.
The node initial stiffness of the web thickness 3.2 Creating strengthen the ring steel pipe concrete node stiffness calculation model At present, the theoretical analysis of semi-rigid steel frame joints have been maturing CFST column - steel beam joint with pure steel structure node there are some of the same mechanical properties, in the reference model of pure steel structure node, according to the previous computational analysis, select a power function model to strengthen the ring steel pipe concrete column node M-θ curve expression Mu connection limit bending moment carrying capacity (N•mm); M value for the node at the moment (N• mm); θ beams and columns relative rotation angle (rad); C1 = 37.699, C2 = 18.831 K is a normalization constant, is determined by the following formula K = d-0.2005ts0.6079bj0.3349h1.3329b0.7141t0.6879 Where d is the CFST column diameter (mm); ts for the steel pipe wall thickness (mm); bj to strengthen the ring width (mm); h for beam high (
In all influencing factors, the impact of joint stiffness beams sectional height, and the thickness of the beam web almost no effect of joint stiffness

The results could provides the test data and theoretical basis for the mechanism of the processing performance affected by the dynamic behavior of machine tools.
In the machining process, there are many factors (the status, pose and cutting parameters of the tool, workpiece materials etc.) to affect the magnitude and direction of the cutting force.
In the case of cutting force no mutations (in the change of normal range), along with the extension of time, cutting tool wear and other factors, solve the reliability of the model.
This provides the test data and theoretical basis for the mechanism of the processing performance affected by the dynamic behavior of machine tools
Chinese Mechanical Engineering, 2008, 9(16):1908-1911

It was also observed that different input parameters have pronounced affect on the formation of oxide scale inside the steam generator tube.
It was also observed that due to formation of scale the thermal conductivity in the boiler tubes was affected and the remaining life of boiler tubes was decreased and accelerated creep damage.
The trend was same for all the models, however the affect was more severe with the increase of both the flue gas and steam temperature.
As stated earlier, the building of scale around the inside wall of the tube causes a layer of material with different thermal properties compared to the original wall itself.
One of the controlling factors for the development of scale is the effect of temperature as shown in Fig 3.

Among the various surface techniques, electroless Ni-P plating is of special interest due to its good properties and convenience.
The two kind of time and deposited time were used as three factors of the orthogonal test, and each factor include three levels, the orthogonal test was carried out.
Table 2 shows details of the factors and levels.
Table 2 Factors and levels of the orthogonal test Levels Factors pickling time (A) (s) activated time (B) ( min ) deposite time(C) ( h ) 1 30 2 1.0 2 40 6 1.5 3 50 10 2.0 Firstly, the substrate specimens were treated for 10 minutes in the degreasing fluid with temperature of 70-80 Celsius degree.
K1, K2 and K3 means average value of evaluation result of corresponding level of every factor.

A two-story frame column longitudinal reinforced HRB400, three-tier framework of beam longitudinal reinforcement HRB335, the stirrups HPB235 reinforced productions, the average mechanical properties of the reinforcement is shown in Table 1.
The model cell size is 0.03 m .for the element shape all hexahedral size model unit deformation of the cell, affect the calculation accuracy.
Fig.5 Geometry plastic-strain chart of frame body Comparison of ductility factor results between the simulation results and the tests is shown in Table 2.
Table 2 Comparison of ductility coefficient results Results Displacement ductility factor Mean of Displacement ductility factor Comparison of results (simulated value / experimental value) Forward Reverse Mean The test results Forward 3.29 3.89 0.824 0.855 0.843 Reverse 4.49 The simulation results Forward 2.71 3.28 Reverse 3.84 Conclusion It’s possible for simulation the reinforced concrete frame structure with specially-shaped columns by ANSYS10.0.

Experimental details The workpiece material is H-13 steel which is widely used in die&mould industries because of its good mechanical and thermal properties.
In order to study the influence of different cutter postures on machined surface topograph, we design single factor experiment of cutter postures.
The roughnesses in different scales are linked with machining process and material property closely.
The roughness of frequency band D6 is almost the largest that means the feed per tooth and radial depth of cut are the main factors influencing the surface topography.
This shows that the changing of cutter postures affects the frequency band D7.