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Numerical Study of Defect Free Elbows Subjected to In-Plane Bending Moment Chen Wanga, YinPei Wangb, PeiNing Lic , Jin Chend, XiaoMing Sune Key Lab of Safety Science of Pressurized System, Ministry of Education，School of Mechanical Engineering, East China University of Science and Technology, Shanghai, 200237, China acwang@ecust.edu.cn, bypwang@ecust.edu.cn, cpeiningli@ecust.edu.cn, dchenjin@ecust.edu.cn, exms@ecust.edu.cn Keywords: Elbow; Limit Load; FE Analyses; In-Plane Opening/ Closing Bending Moment Abstract.
Finite element analysis for elbows In piping system, it is inevitable that the plastic load-carrying capacity of elbows is affected by the constraint of connecting tangent straight pipes, flange and other equipments.
Since the aim of the present work is to assess limit loads and elastic plastic responses, elastic-perfectly plastic material modal is used in this study, with the other material properties chosen, as shown in Table 2.
Material properties The Young’s modulus E [MPa] 2.1X105 Yield stress sy [MPa] 320 Poisson’s ratio ν 0.3 Due to symmetry in geometry and loading, symmetry conditions are fully utilized in the FE models to reduce the number of elements and computing time.
The limit load of elbow with long bending radius (R＝1.5Dm) is greater than that of elbow with the short bending radius (R＝1.0Dm) under the same bending mode and the thickness radius ratio t/rm, but the influence degree of bending radius on limit load is the smallest among the influence factors (R/Dm, t/rm, and the bending mode of In-Plane moment)

Introduction In mechanical process, drilling is the most common process in metal machining.
Then, the motor rotational speed control condition was changed to clarify whether discharge probability is affected by control conditions.
Workpiece material Chrome steel(SCr420) Tool electrode material Copper tungsten Hole diameter (mm) φ3.4 Tip diameter (mm) φ3 Critical speed (min-1) 3200 Control condition (10V-0V), (10V-3V) Open state voltage (V) 100 Pulse frequency (kHz) 1 Discharge current (A) 3.2 Duty factor (%) 50 Polarity Tool electrode(+) Table 2 Experimental conditions 0.4mm φ3mm φ3.4mm 2mm Fig.6 Setting position of tool electrode. 30° Tool electrode Workpiece Fig.7 and Fig.8 shows input voltage and rotational speed chart at control condition 10V-0V and control condition 10V-3V, respectively.
The discharege current, duty factor and machining time are 3.2 A, 50 % and 120 seconds, respectively.
Suzuki, EDM properties of various kinds of polycrystalline diamond (PCD) electrode, Journal of the Japan Society of Grinding Eng.

The friction and wear properties of PEEK and PTFE based composites sliding under rigorous alkaline were comparatively investigated.
The property of sealing materials is a decisive factor in a sealing system.
Many efforts have been made to improve the anti-wear and the mechanical properties of PTFE[12] and PEEK[13] by means of incorporation with various kind of fillers.
Among numerous inorganic fillers, potassium titanate whiskers (PTWs, i.e., K2O·6TiO2) have been found to be promising structural reinforcers for polymers and ceramic composites because of their excellent mechanical properties, wear resistance, chemical and thermal stability[14-16].
Friction and wear properties of these composites were comparatively studied under alkaline solution.

So it becomes the major factor to prevent the door from closing.
Analysis of working principles Loads and deflection analysis on the seals Energy for closing automotive door mostly depends on the compression load deflection properties of the seals.
It consumes much energy which deeply affects on the total energy by the seal system.
So the energy consumed by the venting holes should not be ignored and that the venting holes should be seen as one of major factors in the future research.
Desmet.(2008) ‘Low-frequency dynamic analysis of automotive door weather-strip seals’, Journal of Mechanical Systems and Signal Processing, Vol.22,pp. 1248-1260

However, quality of cast steels is highly relative to fabrication technologies e.g. shrink cavity shapes and sizes were greatly affected by the cooling velocity of cast process and the wear resistance of high Cr cast steel was mostly relative to austenite content [5].
Mechanical properties are around 188 GPa for Young's modulus, 254 MPa 0.2% proof strength, 453 MPa ultimate tensile strength, 26 % elongation, and 45 % reduction of area.
In the test process, test loading level of stress intensity factor range, ∆K, is defined as ( ) max1 KRK −=∆ ; ( )WafWBPK maxmax = ; ( ) ( )( ) ( ) 5.1 4 3 2 126.572.1432.1364.4886.0 αααα αα −+ −+−+=Waf ; Wa=α (1) ×100 150µm c ×100 150µm b ×500 50µm ferrite pearlite a Table 1 Specimen geometries and initial loading levels Specimen ∆K0 (MPam 1/2) R a0 (mm) B (mm) W (mm) 1 7.04 0.1 14.119 10.03 50.02 2 6.90 0.1 14.510 10.02 50.00 3 7.24 0.1 15.049 10.04 50.05 4 7.00 0.1 15.186 10.02 50.05 5 7.00 0.1 13.987 10.03 50.02 B W a aO Fig.2 CT specimen for present study a. a - curve 0.0E+00 2.0E+06 4.0E+06 6.0E+06 8.0E+06 1.0E+07 1.2E+07 1.4E+07 1.6E+07 0 1 2 3 4 ∆a (mm) (cycles) b. da /d -∆K data 1.0E-08 2.1E-07 4.1E-07 6.1E-07 8.1E-07 1.0E-06 1.2E-06 0 2 4 6 8 ∆K (MPa.m^0.5) da /d (mm.cycle^-1) da/dN-∆K data ∆Kmin data Fig. 3 Test a- and da/d -∆K data for the present material.
Table 2 Minimum da/d -∆K data from the present tests Specimen da/d min (mm.cycle -1) ∆Kmin (MPa.m 1/2) 1 1.08×10-7 4.7125 2 1.79×10-7 5.0718 3 1.30×10-7 4.7687 4 1.18×10-7 4.3755 5 1.02×10-7 4.2681 where Pmax is maximum value of a cyclic test load; Kmax is maximum value of stress intensity factor with respect to Pmax.
Test data for minimum stress intensity factor range, K∆ min, values and corresponding crack growth rate, da/d min, values of the specimens are given in Table 2.

Table 1 Compared with the traditional fixed-wing and rotary-wing aircraft property Fixed-wing aircraft Rotary-wing aircraft Flapping-wing aircraft Advantages Fast and stable No take off distance; agile Biomimetic; low noise; low cost; no take off distance; agile disadvantages A long take off distance; High cost; Poor flexibility Noisy; high cost; low speed Affected by airflow Table 2 Compared with aircrafts which imitating insect and hummingbird property Flapping-wing aircrafts imitating insect and hummingbird Bird-like flexible flapping wing aircraft advantages Miniature size High efficiency by flexible flapping; Energy saving by gliding disadvantages energy-intensive; Mechanical Wear Large Difficult hovering Bionics Mechanism and the Design of Flapping-Wing Aircraft As the structure of the bird’s wing (Fig. 1), the feather would open and close while flapping, and the three joint bones would bend while flapping upward and stretch while flapping downward, this could decrease the resistance
A Summary of Factors Influencing Lift and Drag of the Aircraft 1.
Aerodynamic parameters are modeled and used to analysis the influence factor in the flapping process.

Web-based Case Report Form Design For Clinical Trial Lingli Fu1,a, Tao Chen2,b 1Department of Computer Science and Software, Hebei University of Technology, Tianjin, China 2Department of Mechanical Engineering, Hebei University of Technology, Tianjin, China aamy_fu@163.com, byesonme@gmail.com Keywords: clinical data management, electronic data capture, electronic case report form.
The design of the CRF is a critical factor in the capture of high quality data in clinical data management.
CRF must be changed corresponding with the contents of protocol changed that will affect data collection. 2) Only collect information related with project research, and avoid collecting unnecessary information, reduce duplicated and interactive information.
In addition, questions format and order should be reasonable, and consistent with business and clinical trials procedures. 4) Design the objective-based and quantitative problems as far as possible, which will avoid the influence of subjective factors on the clinical data.
In design, there have some display properties for particular items, such as text, multi-text, radio box, check box, select box.

The mechanical properties of WPC are influenced by many factors, such as the moisture content of the raw materials, temperature in processing and molding pressure, When wood powder moisture content is higher, the process is more prone to "bridge" and "hold stem" phenomenon, and this charging discontinuous can make products production down and reduce the performance.
The conveyor plate conveying materials affect analysis Tab.3 The gliding angles of wood powder, PVC, the mixture of wood powder and PVC when they slide from the top surface of the conveyor plate at each heating temperature T /℃ angle/° 40 50 60 70 80 90 100 110 120 130 140 wood powder 25 24 22 20 22 21 20 21 20 22 22 PVC 26 27 29 31 37 glue the mixture 26 20 20 21 23 22 23 23 glue It could be saw that PVC and the mixture of wood powder and PVC glued with conveyor plate respectively at the heating temperature 90 ℃ and 120 ℃from table 3, sticky materials effect as shown in figure 3 and 4. it was just that PVC softened at 82 ℃and adsorbed on conveyor plate, but mixture began to stick material at 110 ℃.
(3)The friction coefficient of the mixture of wood powder and PVC is much smaller than PVC powder alone in the transmission process, because the PVC is easy to soften and sticky, synthesizing every factor, selecting 80 ℃ as the drying temperature of transportation and the effect is best.

Such wear coefficients may theoretically depend on rolling process factors such as, strip temperature, strip grade, roll type, roll oxidation or roll-bite lubrication [9,12,14].
Though, neither analytical relation linking these factors nor details about the parametrization of the wear coefficients (by considering the variation of these factors during the rolling process) are generally provided.
The wear tuning coefficient K of the chosen wear models can be defined by relating multiple rolling factors.
However, 3 different parametrization approaches have been established to link these rolling factors.
In other words, the amount of wear generated by a same rolled strip (and same rolling conditions) at the beginning and at the end of the rolling campaign should be different due to the weakness of the thermo-mechanical roll properties.

A Flow-Dependent Secondary-shortest Path Algorithm for Naval ship Evacuation Chong Liu1, a, Changhua Qiu1, b 1College of Mechanical and Electrical Engineering, Harbin Engineering University, Harbin, Heilongjiang, 150001, China a liuchong@hrbeu.edu.cn, b qiuchanghua@hrbeu.edu.cn Keywords: Navy ship Evacuation, secondary-shortest Path, flow-Dependent Network optimization.
There is a great deal of factors that come into play and can affect the efficiency of the evacuation.
Unique to naval ship situations, the first evacuee group to travel a closed door or hatch will incur a delay, the group size and the flux of the door will also affect the evacuee travel time [4].
The main idea of this algorithm takes into account the following property: the second shortest path p2 in G is the shortest path in a new network G', obtained from G removing the shortest path p1[7].Let’s define G'Path as the final set of shortest path Bg', g'∈G', G' is a set of evacuee groups who requires secondary-path planning.