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Liu et al. proposed a quantitative-feedback-theory-based tracking control scheme to eliminate the mechanical vibration of XY table [6].
In that case, some neglected secondary factors in normal conditions could become key issues affecting dynamic performance.
And the residual vibration caused by high speed movement would seriously affect the positioning accuracy and stabilization time of the XY table.
So the x-axis position system motion produces the most significant mechanical resonance.
The achieved results are: For the complex electromechanical coupling system, the oversimplified analytical model could not reflect the actual physical properties of the system.

CRH2 type EMU was taken for example to discusses the important principles of ecological design from aspects of environment factors, modern humane ecological design, design methods and material technology.
Ecological design means environmental factors should be contained in the design, which can be used to determine the direction of design decisions.
Ecological measures and ecological factors of the design could be determined better according to a number of different external factors.
(c) Perfect property of anticorrosion can omit the coating design for the body.
The key of optimizing design process, using material or energy reasonably, minimizing the negative effect on the environment as well as human health, is the systematic analysis of the external factors that affect the product life cycle.

Injection Speed Control of Precision Injection Molding Based on CMAC Neural Network Kaiyuan Chen1 ,Mengxue Yan2 ,Ying Wang3 and Nanqiao Zhou4 1,2,3Department of Mechanical and Electrical Engineering, Foshan Polytechnic College, Foshan 528137, China 4Key Laboratory of Polymer Processing Engineering of Ministry of Education, National Engineering Research Center of Novel Equipment for Polymer Processing, South China University of Technology, Guangzhou 510640, China Keywords: CMAC; neural network; injection speed; PID control Abstract: Injection speed is one of the most important parameters during precision injection molding.
Introduction Precision injection plastic parts are widely used in many fields including machinery, electronics, communication and automobile because they have many advantages such as good mechanical property, high precision and superior dimensional stability, which replace part of high precision metal parts.
When the mathematical model of the controlled object changes and becomes nonlinear, the adjustment of PID controller is difficult according to the actual situation, which affects the control quality.
W refer to the CMAC network link weight matrix, and the parameter can be adjusted, then the i number of output can be described as (2) The learning algorithm for the CMAC network link weight matrix can be shown below: (3) where k is learning cycle, i is the number of output variable, j is the number of CMAC neuron, is learning factor with a value between 0 and 1, is desired output, is its actual output., and is vector of correlation space.
When the nozzle temperature decreases to 220℃, which affects the melt flowability, and the parameters of the control object change, from Fig. 5 it can be seen that the adjustment time of step response of injection speed using conventional PID control algorithm delays significantly, but the adjustment time using compound control algorithm of CMAC and PID almost remains unchanged.

For potential technology applications, YIG material was modified by substituting with rare earth elements to affect their magneto-optical, electrical and magnetic properties.
The magnetic properties of the sample were measured with vibrating sample magnetometer (VSM).
This behavior is attributed to the synthesis method and other factors that promote changes in the magnetic order of the cationic moments.
Magnetic properties of NdxY(1-x)Fe5O12 (x = 0.0, 0.2, 0.5, 0.8).
‘x’ Magnetic Properties Hc (kOe) Ms (emu.g-1) 1.

Based on the ray-tracing simulation, the luminous flux, CCT and ACU affected by the phosphor thickness, concentration and concentration distribution were obtained and studied.
Zong-Yuan Liu et al researched the luminous efficiency and color mixing fraction of conformal coating phosphor LED affected by phosphor thickness and concentration using optical simulation [5].
As far as we are concerned, there are few articles involved the ACU of conformal coated LED affected by the phosphor thickness, concentration and concentration distribution.
The reflection coefficient and absorption coefficients of the cone reflector cup were 0.95 and 0.05.The refractive index and scattering index of the phosphor silicone gel are very important as they determine the optical properties.
For some specific application, angular color uniformity (ACU) is an importance factor of the LED performance specification.

Introduction The misorientation angle between adjacent grains of steels, has become one of the major concerns for the study of some mechanical and toughness properties of irons [1-5], carbon steel [3, 6], stainless steel [7-8], other types of steels [8-10] and different alloys [11-12].
It can be observed that one of the major factors that make up the constitution of ferrite grains, different to its size, is their orientation with respect to their neighbouring grains.
This property has a strong influence on steels with low mechanical properties such as mild steels, like Grade A ship plate steels used for the construction of merchant ships.
Fig. 13c also shows that the twist boundary strongly affects the surface appearance of a steel and consequently the fracture toughness properties of the steel because, as mentioned above, twist boundary offers more resistance for cleavage propagation.
Ding et al., The effects of grain boundary misorientation on the mechanical properties and mechanism of plastic deformation of Ni/Ni3Al: A molecular dynamics study, Materials 13 (2020) 1–21

Specific properties of fly ash was determined using calorimetric measurement.
It was determined heat properties and total content of calcium oxide CaO.
Evaluation of properties of fly ash.
The combustion is not stable and it depends on the operation of power plants that the properties of fly ash are affected. 2) From a comparison of the ash ETH 10 and ETH 20 shows that they have different content of free CaO.
Zaldívar-Cadena et al., "Effect of Milling Time on Mechanical Properties of Fly Ash Incorporated Cement Mortars", Advanced Materials Research, Vol. 787, pp. 286-290, 2013 [9] K.

Prediction of Particle Impact on an Archimedes Screw Runner Blade for Micro Hydro Turbine Muhammad Ammar Nik Mu’tasim1, a, Nurul Suraya Azahari2,b and Ahmad Alif Ahmad Adam3,c 123Computational Analysis Group, Faculty of Mechanical Engineering, Universiti Malaysia Pahang,Pekan, 26600 Pekan, Pahang DarulMakmur.
The turbines extract energy from the fluid and change it into energy such as mechanical energy output and usually in rotating form or shaft.
Another factor that decreases the efficiency is due to erosion.
Previous researcher[4] states that the characteristics of the channel flow properties is observed in portable wind tunnel with rainfall simulation by using Reynolds-averaged Navier-Stokes (RANS) k-ε turbulence model.
The velocity vector was affected by the turbine blade as the stream of the turbine hit the wall and at the same time the velocity vector diverged in two direction which is upper and lower vertices.

After a comprehensive consideration of various factors, including variation of energy efficiency, room volume, air outlet size, and that the maximum air exchange rates of different rooms are fixed.
Fig. 1 Simulation model (source [2]) Table 1 Construction parameters of the simulation model Room Room area(m2) Orientation Area ratio of window to wall Window material Main bedroom 13.11 Southeast 0.28 Co-extruded hollow aluminum window Subaltern room 11.38 Northwest 0.33 Living room 39.33 Northwest 0.43 Single-layer aluminum window Table 2 Thermal performance of envelope Component Roof Exterior wall Interior wall Co-extruded hollow aluminum window Single-layer aluminum window U-factor( W/ (m2•K)) 2.18 2.69 1.52 2.9 6.5 Air Conditioning and Ventilation Schedule.
Since the air exchange rate is related to room volume, size and position of air outlets and so on, and considering the height of each floor in residential building is limited, no-pipe mechanical ventilation is more appropriate due to the mechanical ventilation with pipes installed in the ceiling, which then causes a need to do ceiling decoration.
Outlet size not only affects the appearance of the building, but also directly determines the supply air velocity, if the air quantity is large and the size of the outlet is limited, the wind speed of air inlet can be too strong, and even unsafe.
In the future, this method can be used in any typical residential buildings of Guangzhou so as to determine the approximate range of parameter a, b and c in the above function, and also the effect of construction factors to each parameter could be analyzed by this way, such as building orientation, floor, function of rooms, thermal properties of envelope.

Introduction Epoxy resins, due to the possibility of their modification, due to the presence of reactive hydroxyl and epoxy groups, with the production of materials with high physical and mechanical properties, are still the most promising among other organic high molecular weight substances [1-3].
Composite materials based on epoxy oligomers are widely used in practice due to high adhesion, high heat resistance, low brittleness, low shrinkage during curing, stability of technological properties and several other properties.
Due to such properties, materials based on epoxy resins are widely used in various industries: as film-forming substances in the refining industry, shipbuilding, construction, etc. [4,5].
Obtaining epoxy polymer composites for construction purposes with predetermined properties is usually associated with the use of physicochemical modification methods: the introduction of solid insoluble fillers and fillers, surfactants, inert plasticizers and thinners [6-8].
The elastic properties as well as the impact strength of matrix composites depend on various factors: temperature conditions of curing, mechanochemical effects during the hardening process, but to a greater extent on the type of hardener and its concentration.