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One of the main problems for this system design is to measure long-time dynamic response signals and simultaneously estimate the structural dynamic properties.
In general, damage identification methods for structural health monitoring involve the structural dynamic properties.
Dynamic properties, such as natural frequencies, damping coefficients and mode shape, are directly related with structural stiffness or mass matrix.
To provide a common base of reference for the before and after damage cases, the eigen-values are used as normalization factors for the eigen-vectors.
Structural damages affect all three modes; especially, the first mode is dropped into 0.976.

It is known that the ultra-fine-grained structure in the material has increased physical and mechanical properties, which, in turn, favorably affects the quality of surface layer [4-12].
As a study of the roughness parameters of the machined surface was taken into account the following factors: arithmetical mean deviation of profile Ra µm; root mean square roughness – Rq, µm; the maximum height of the profile Rmax, µm; measured the height of irregularities Rz, µm; average step of roughness – Sm, µm.
R. 2018 Improving the performance properties of titanium alloy on the basis of grinding grain microstructure and surface modification. : dis. ...
Z. 2016 UFG structure and mechanical properties of magnesium alloy MG-1% CA.
Reception, structure and properties M. : Akademkniga.

The underlying factors for a stable buildup are local heat transfer, powder catchment efficiency, surface shape, roughness, and oxide layers.
However, martensitic steel is gaining more and more importance in turbo machinery parts due to its outstanding mechanical properties [6].
The lower the geometric factor κ, the lower the applied laser power.
According to the Hall-Petch rule [11], a homogenous microstructure indicates homogenous mechanical properties and a finer microstructure would lead to higher hardness.
This leads to the assumption that the martensite formation that mainly affects the hardness is mostly driven by the local heat flow during the solidification of the a melt pool and less by the global heat flow and geometry.

The microstructure is one of the factor concerning to cold cracking problem.
The first application is the tracking the microstructural change along various thermal cycle simulating heat affected zone.
These factors contribute to fine microstructure formation.
Thus, to secure good mechanical properties in the weld metal, it is important to understand the mechanism of intragranular acicular ferrite formation.
And it is expected that the acicular ferrite is formed in the heat-affected zone.

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.

Primary factors have a direct effect on the fretting process, whereas the secondary factors are only indirectly linked to the primary factors.
Table 1 gives the elastic properties of these materials.
Materials Properties.
Fatigue properties for 2014-T6/651 Aluminum alloy [11].
This research has found two factors to be responsible.

The resistance strain gauge is a key component of dynamic weighing system, but because of the resistance strain gauge temperature properties and long-term stability and so on some technical indicators can not meet the high accuracy of performance requirements for weighing sensor.
Variable, nonlinear and the random interference factors are contained in dynamic weighing process.
When the weighing speed is accelerated, vibration caused by the material impact and uncertainty of material in the air will affect the weighing precision, so in order to improve the weighing accuracy, sometimes it will have to lower the weighing speed.
There are many uncertain factors weighing process, such as mechanical parts have inertia characteristics, the weighing signal has a lag and the falling material has an impact on the scale body etc.
Because the instability caused by the incoming flow of the material and the pure lag from the mechanical inertia, it is very difficult to improve the control precision.

Analysis of Optimal Clamping Schemes for Aero-Multi-Frame Monolithic Components Hun Guo 1,2,a, Dunwen Zuo 1, Guoxing Tang 2, Min Wang 1 and Yangjing Guo3 1 College of Mechanical & Electrical Engineering, Nanjing University of Aero & Astron, Nanjing, China, 210016 2 School of Mechanical & Electrical Engineering, Changzhou Institute of Technology, Changzhou, China, 213002 3 Beijing Huayuanyitong Heating Supply Technology Development Co., Ltd.
Many researchers emphasize on investigating how clamping points, clamping order, and clamping force affect in-process dimensional precision and setting accuracy [5-8].
But they only focus on single factor, the combined factor of clamping force and milling force has been not considered.
The geometric dimension, its property value and the working parameters are listed in Table 1.
This study conclusion has been validated by the actual production. 3) But in this study other factors except for clamping force have been not considered, so this model need to still perfect further so that it is the purpose of this publication to address those specific needs of studying workpiece fatigue resistance in next study.

Introduction : BaZrO3, a refractory ceramic has good mechanical strength and chemical stability with a small coefficient of thermal expansion.
Newer methods are thus being tailored to produce nanocrystalline ceramics having sinterability at lower temperatures, phase homogeneity, fine particle size, unique magnetic, electrical, mechanical and optical properties.
From the experiments, it appears that a number of factors affect the variation in the reaction product formation, predominantly heat evolved, maximum reaction temperature, local O2 and CO2 concentration, redox reactions and heats of formation and decomposition of reactants and products.
Further investigating studies are required to co-relate these factors and predict course of reaction.

Uncertainty Evaluation of SEM-based Nanoroughness Measurement Fengxia Zhao 1, a, Qinghai Wang 2,b, Linna Zhang 1,c and Peng Zheng 1,d 1 School of Mechanical Engineering, Zhengzhou University, Zhengzhou, P.
China, 450001 2 Henan Mechanical and Electrical Vocational College, Zhengzhou, P.
The SEM first focuses an electron beam whose cross-sectional radius is very small (5-7nm) and then scans a sample in a raster way, producing information which is related to the properties of the sample.
Because an SEM image is formed from the interaction of incident electrons and a sample material, there are several factors, such as the wave character of incident electrons, magnification, scanning speed and resolution, etc, which contribute to uncertainties in the precision of nanoroughness measurements.
Suppose every two uncertainty factors above mentioned are non-correlated, then according to uncertainty combination equation presented in ISO GUM [6] the total uncertainty of SEM-based nanoroughness metrology can be derived from (1) Where is the uncertainty of extraction operation, is the uncertainty of filtration operation and is the uncertainty of fit operation.