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Several parameters of casting process such as melt superheat, preheating temperature of mold, thermal conductivity of coating and flux powder, which affect the temperature distributions in both cast pipe and mold and the changed positions of melt solidifying at last are investigated.
Schematic diagram of the calculation for the angle factor.
Pittman: Configuration Factors for Exchange Radiant Energy between Axisymmetrical Sections of Cylinders, Cones, and Hemispheres and Their Bases (NASA Tech.
Mills: Recommended Values of Thermophysical Properties for Selected Commercial alloys (ASM Int., U.S. 2002)
Wada: Summary of Thermal Properties for Casting Alloys and Materials (National Technical Information Service, U.S. 1982)

Alloying Elements such as Mn, Ni, Cr and so on, which can affect the characteristics of phase transformation of steel, are added into steel in order to obtain optimum microstructure and mechanical properties.
As the kind of common micro alloy element, vanadium is used to improve the properties of steel, such as strength, wear resistance and so on [1-3].
Numerous researches reveal that [4-9], vanadium exists in the steel as the form of solid solution and carbonitride; In addition to the solution and precipitation strengthening, vanadium can notably affect the characteristics of phase transformation for steels.
But the diffusion coefficient of vanadium atoms is about 5 orders of magnitude lower than carbon atoms, therefore the diffusion and distribution of vanadium is one of controlling factors of pearlite transformation for heavy rail steel.
Materials for Mechanical Engineering.

Whilst the strongest tendon on the body, the Achilles tendon (AT) is also one of the tendons that are most commonly affected by spontaneous complete rupture [1, 2].
The model comprised of 13 segments, 12 joints and 23 degree-of-freedom (DOF) mechanical linkages, which enables enabled movements in the sagittal, frontal and coronal planes, and was actuated by 54 muscle-tendon units.
Biomechanical properties, such as viscoelasticity and tensile strength, are integral to tendon function and attributable to elastin and collagen fibres and their metabolism.
Due to the viscoelastic properties of the tendon, this high strain rate may result in large amount of stress, which is one of the major injury factors for acute Achilles tendon rupture.
Munro: Dorsiflexion Capacity Affects achilles tendon loading during Drop Landings.

Generally energy is lost in all kinds of brake systems (mechanical or hydraulic).
Hydraulic accumulators are characterized by a high value of energy that can be accumulated and recovered, combined with the properties of hydraulic control systems, enabling smooth control ratio, allows for the construction of drives, which are characterized by favorable properties.
From the several models of gas, after previous analysis, the most suitable Van der Waals model is used in simulations of the accumulator pneumatic subsystem [4]: (6) where: a – cohesion factor, b – co-volume factor.
Differentiating the equation of state we obtain the dependence on pressure increase: (7) Simulation studies of hydro-pneumatic accumulator properties Simulation tests are designed to answer the question, what parameters and how they affect the efficiency of the accumulator, then how to choose the optimal parameter values due to the efficiency of the accumulator in the drive system, which is a secondary energy source, in presence of varying, as a function of time, load of the hydraulic drive system.
The model allows us to calculate the characteristics of the parameters of the system and to determine the effect of both the accumulator design parameters such as shape, material properties and the properties of the process cycle, on efficiency of energy recovery.

The major factors which affect the efficiency of the antimicrobial additives are their migration rate and velocity in the polymer, the hidrophobity of the surfaces, and numerous interfacial phenomena.
These factors may motivate many researchers from many parts of material science because of the possibility and need of professional measure methods and instruments.
The antimicrobial property of a plastic is usually achieved by blending with antimicrobial agents, and the migration rate and velocity properties of these additives are the key factors of the effectiveness.
For the customers, it is very important that the chosen additive has to kill all microorganisms that may grow at the prospective conditions (and harmful to humans), do not migrate too fast, but do not seize in the matrix, and enhance, or at least do not worsen the technological, mechanical and optical properties of the product.
Evaluate the effect of biocide for the technological, mechanical and optical parameters of the plastic, measure the diffusion rate. 5.

The system’s interface, designed using C++ Builder, can access data which includes the geometrical angles and dimensions of tool, the sizes of work, the relative position between tool and work, properties of tool and work, cutting conditions, etc..
It is known that modeling is one of some key techniques, in which geometrical angle and structural parameters of cutting tool are important factors.
It directly affects the operation and results of the simulation system.
It is necessary to configure properties of material.
Before the simulating of machining process, geometric properties and material property of elements, contact relationship of bodies, mechanics and thermal conductivity between milling tool and workpiece need to be defined and evaluated.

These properties could be accomplished by a series of several technological precautions, one of which is the composition of the concrete mixture itself.
These properties are vital for the construction of white boxes.
A number of factors, such as properly designed construction and its flawless implementation, as well as the proper design of the concrete mixture composition itself, ensure the hydro-insulation property of a functional white box. [1] Properties such as low water absorption, high resistance to groundwater penetration under pressure and low volume changes are extremely important for these types of concrete.
The Analysis of Used Additives The experiment verifies the basic properties of hardened concrete associated with the water impermeability of white boxes.
These properties are shown in the diagram below and in Table 1.

With a long-span prestressed concrete T-rigid frame bridge as studied object, based on the display analysis function of the LS-DYNA software, this paper represents the simulating process of the contact and collision between the drift-ice and T-rigid frame bridge pier, and the influence of various factors was analyzed, such as model boundary condition, contact types of river ice and pier, algorithm and element connection transition area.
Affected by a number of factors, the strength of river ice, the failure form of ice sheet, the speed and direction of wind, the flow rate and direction of water and ice sheet, as well as the forms of bridge pier and ice-breaking mass.
The ductile brittle transition is an important property of river ice, the river ice fails in ductile style at low strain rate, while is brittle at high strain rate.
The mechanical properties tests of river ice indicated, the ductile to brittle failure of demarcation point of strain rate of the river ice is from o.0476x10-3s-1 to 0.952x10-3s-1[8,9].
Experimental research on mechanical properties of river ice.

The block not only meets the design requirements, its physical and mechanical properties and quality also meet such standards as “Normal concrete small hollow block(GB8239-1997)”, “Lightweight aggregate concrete small hollow block(GB15229-1994)” ,and “Small fly ash hollow block(TC862-2000)”.
The mixing quality is to determine the main factors of the block stable quality, in order to ensure the uniformity of the mixture, we should divide the mixing in 3 steps.
The carbonation of fly ash concrete block usually refers to that the CO2 in the air and Ca(OH)2 in the cement react to generate CaCO3 and water in the presence of water.With the carbonation, the Ca2+ concentration in the fly ash concrete is reduced, in order to maintain the balance, Ca(OH)2 will continue to dissolve, the above process continued, resulting in the liquid phase alkalinity and the alkali would to reduce, to a certain extent, the surrounding other calcium hydration products will decompose, carbonation, thus affecting the durability of concrete.
Beijing:Goal Preparation Technology,2002. ( In chinese) [3] Danshen Shen，Zhene Chan.The cement consists of fly ash[M]. the Science & Technology Press in Shanghai,1992. ( In chinese) [4] Peiyun Chi，Feng Liang,Shikuan Lu.The Test Study of High Properties and Green Concrete With Big Ratio Fly Ash[J].Fly Ash in CHINA,2002(3)：54～55. ( In chinese) [5] Jueshi Qian.

Because there are differences in the physical and mechanical properties of soil, in different types of geotechnical media, the development of these phenomena in quantity are not identical.
Experimental methods can determine the equation of media properties, including dynamic and static compression curve σ (ε) equation.
(1) (2) Where is peak particle velocity (ft/sec), is the peak acceleration (g), f is coupling factor, c is seismic wave velocity, is the distance to the explosion (ft), W is the charge weight (lb), n is attenuation factor of soil. f is 1; c is 1000ft/s, n is 2.75, W is 500.44 lb.
One reason is that the element size affects numerical results.
This will affect the numerical results.