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The precision processing machineries often require a stable working environment, because vibration is an important factor on reducing system performance.
For example, in the precision optical equipments, small vibration will affect the focus, and excessive vibration will cause the destruction of the system structure.
Another advantage of air spring is that the energy-storage capacity of air is much greater per unit weight than that of mechanical spring material, so that the pneumatic isolation system can result in a natural frequency for the system which is much lower than the vibration isolators made by mechanical springs [2].
The valve’s response affects the accuracy of the system significantly.
Dynamic Model of the PWM Pneumatic Isolation System Principle of Pulse Width Modulation (PWM) Modulation is the process of varying one or more properties of a transmission data signal with high frequency periodic waveform.

., Ltd, Changwon, Gyeongnam, Korea 2 Faculty of Mechanical & Aerospace System Engineering, Chonbuk National Univ., Chonju, Chonbuk, Korea a parrot@doosanheavy.com, bchjoo@doosanheavy.com, cH107527@doosanheavy.com, d yuhs@moak.chonbuk.ac.kr Keywords: Dissimilar weld joint, Filler metal, PWHT, Creep rupture strength, HAZ, T23, T91 Abstract.
In the viewpoint of boiler tube materials, economic component design for high temperature applications often entails the use of materials with different high temperature properties and costs and results in dissimilar weld joints.
This paper is concerned with the evaluation of material properties for T23/T91 dissimilar metal welds being newly used in the region of 600 o C and the estimates have been carried out to determine the optimized condition for post weld heat treatment (PWHT) holding time and to investigate the effect of filler metal for high temperature performance.
The Charpy tests that each notch was located at weld metal, T91 side heat affected zone (HAZ) and T23 side HAZ also showed satisfactory results above 30 Joule.
As a result, it was shown that stress reduction factor due to this type IV cracking could be 50% for 100,000hours test.

It is hard to get good adhesion and plastic property between copper layer and steel core.
It is necessary to make a finished product through the heat treatment in continuous drawing processing, it is easy to cause coating falling off or cracking, the mechanical properties and electrical characteristics of CCS are affected.
But because the thickness of copper coating layer are affected by some factors such as the temperature of steel, the temperature of liquid copper and the height of liquid surface[17], it is difficult to control the process.

Fig.1 Picture of the cantilever, Fig.2 Schematic diagram of CRAS, Fig.3 Picture of CRAS platform Table 1 Dimensions and physical properties of the cantilever Dimensions (mm) Density (kg/m3) Young modulus (GPa) Poisson ratio 600(L)×120(W)×20(H) 7800 214 0.33 Classical CRAS experimental modal test for modal frequency of the cantilever Experimental modal analysis of the real structure lies in that exciting force and moving response of each discrete excitation point are measured simultaneously, as the real structure is excited by hammer.
CRAS represents a computer random signal and vibration analytic system, which combined with vibration trial, data processing and computer, for experimental modal analysis of physical mechanical structure.
However, the fifth stage of modal frequency is lower than experimental modal test schemes, because that the mass of sensors would significantly affect the results
(3) For experimental modal test, many influencing factors would affect the results, including excitation position, force, direction, position of the sensors glue-attached on the cantilever, the stiffness and the isotropy of the cantilever, the property like adhesiveness and thickness of the glue, the mass of the sensors, stability of the system.

Introduction Silicon carbide (SiC), particularly 4H-SiC, has in the recent years been in focus due to excellent electronic properties.
The change in volume at the sphere origin can be expressed as ( )33 3 4 hs rrv − =∆ π (2) This change of volume will affect the radius of the sphere of radius R.
Several techniques for calculating the critical thickness of an epilayer have earlier been presented [4,5] but these techniques have mostly been based on mechanical equilibrium of a grown-in threading dislocation that determines the onset of interfacial misfit dislocations.
The screw dislocation was chosen since it has lower energy density than the pure edge dislocation by a factor of 1/(1-ν) [6].

Introduction Hamilton equation plays an important role in the physical modeling, and generalized Hamiltonian system describes the more widely dynamic system in[1], Compared with the traditional differential equation, generalized Hamiltonian systems differential equation is equivalent to traditional differential equation, but its structure and damping matrix provide internal coupling dynamic mechanism for system, Hamiltonian energy function can be used as Lyapunov function in some conditions, Therefore, through the establishment of the generalized Hamiltonian model to study the stability and control of the system is a new approach, On the aspect of generalized Hamiltonian system modeling theory, how to determine the Hamiltonian function is a core problem, because without a proper Hamiltonian function, the Hamiltonian system obtained can't reflect the system dynamic properties of internal relationships correctly.
Changing the circuit parameters and time constant of transfer function, some group of simulation results may be obtained, by analysis, the simulating response characteristics of equivalent circuit and the transfer function are consistent in step input ,while the former inhibition is stronger, but this factor does not affect the energy relationship of entire branch.
(9) (10) (11) Where δ is the rotor (rad), D is the damping coefficient, rf is the resistance of excitation winding in per unit, Tj is the inertia time constant (s), ωB is the base value of angular velocity, ω1＝ω-1=Δω, ω is the angular velocity in per unit, mt is the mechanical torque, uf is the exciation voltage in per unit, the pf in (11) is the generalized momentum of excitation winding, defined as: pf =Xf Eq´/Xad.

It was assumed that impact of the sample size would affect the supporting bodies, so called size effect [3].
Wu, "Experimental Study on Size Effect in Strength of Pervious Concrete and its Associated Factor", Advanced Materials Research, Vols. 634-638, pp. 2684-2692, Jan. 2013
Bittner et al., Experimental Investigation of the Mechanical Properties of Textile Glass Reinforcement, Applied Mechanics and Materials (2015), Vol 732, pp. 45–48, 10.4028/www.scientific.net/AMM.732.45

Analysis of organic pollutants from biologically treated coking wastewater in a multiple barrier method Huiqin Zhang1,2,a, Chunsong Ye1,b, Fan Yang1, Xian Zhang1, Hong Yang3,c and Guangrong Liu1 1School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072, China 2Hubei university of technology, Wuhan 430068, China 3CSIC Environmental Engineering Co.
Table 1 The properties of coking wastewater biologically treated pH COD (mg/L) TOC (mg/L) Turbidity NH3-N (mg/L) Total hardness (mg/L) 7.70 790.0 129.1 151 112.6 696.4 2.2 Materials and instruments The solutions were prepared with FeCl3 (AR, ≥99.0%), APAM (AR, ≥85.0%), FeSO4·7H2O (AR, ≥99.0%), H2O2 (AR, 30%, w/w), CH2Cl2 (AR, ≥99.5%) provided by National Pharmaceutical Group Chemical Reagent Co., Ltd (Shanghai, China).
Results and discussion 3.1 the CF process FeCl3 and APAM were selected as coagulant and organic polymer coagulant-aid in the CF process[12]. the purpose of this experiment is to investigate the effect of the coagulation elixir on the COD removal of coking wastewater (Fig. 1), the optimized concentration of APAM was fixed to 0.8 mg/L discussed by single factor experiment, the Fig. 1 showed that 320.0 mg/L of FeCl3 solution with the pH value approached to 3.5 was best in the CF process and the COD removal increased to 72.0%.
The pH value limits the performance of FO process and affects the speciation of iron and decomposition of H2O2[15], the water sample after FO process contains a lot of iron ion and pH was 3.0-3.5.

Its reliability is a key factor for the safe operation of the ship.
Smith et al.’s (2005) work aimed at describing how much a conceptual decision may affect the improvement of reliability.
Zhu et al. (2017) presented a comprehensive review of the state-of-the-art online sensors for measuring lubricant properties (e.g. wear debris, water, viscosity, aeration, soot, corrosion, and sulfur content) [20].
Pawashe et al. (2017) discussed the oil fault diagnosis techniques and change of oil properties and contamination [21].
Fenton, ‘Applying Bayesian Belief Networks to System Dependability Assessment’, in Safety-Critical Systems: The Convergence of High Tech and Human Factors, F.

This factor can interfere directly in the properties of the material obtained.
Rossi, Magnetic properties of Fe3O4 nanoparticles coated with oleic and dodecanoic acids, J.
Pandey, Influence of crystallite size on the magnetic properties of Fe3O4 nanoparticles, J.
Quíjada, Study of the Influence of Magnetite Nanoparticles Supported on Thermally Reduced Graphene Oxide as Filler on the Mechanical and Magnetic Properties of Polypropylene and Polylactic Acid Nanocomposites, Polymers (Basel). 13 (2021) 1635
V Ramanujan, Magnetic nanostructures: Synthesis, properties, and applications, in: Springer Handb.