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Methods Determining the Weights of Characteristics in Mechanical Products Design on Case-base Reasoning Aimin Jia, Kun Zhub and Quansheng Huangc College of Mechanical & Electrical Engineering,Hohai University, Changzhou, Jiangsu,213022,China ajam@ustc.edu, bzhukun80074925@126.com chuangquans@126.com Keywords: Case-based reasoning, Weights of case characteristics, Analytic hierarchy process, Roughness set theory, Combination weighting method.
It is more obvious in some areas which mechanical experiences occupy a certain position.
Subjective weighting assignment is given subjectively by experts according to experiences and practical judgment of themselves, therefore it maybe affected by some factors like experts’ mood and outside environment and the result is often different of everyone.
Some definitions and properties of related conceptions are as follows: (1) The conception of equivalent set ① The definition of equivalent set Definition 1: for （one or some attributes included in A）, is true, so objects and are equivalent about attribute set A.

Cooling rates during quenching contribute to the development of final microstructure and hence mechanical properties.
It is therefore necessary to design and optimise heat treatment processes to ensure the best possible mechanical properties are obtained homogenously.
Date, Modeling of microstructure and mechanical properties of heat treated components by using Artificial Neural Network, Mater.
Talamantes-Silva, Use of controlled heat treatment to predict mechanical properties in steel components, Ironmak.
Hong, Effects of alloying elements on mechanical and fracture properties of base metals and simulated heat-affected zones of SA 508 steels, Metall.

Thermo-mechanical experiments were carried out to study the effect of deformation speed and temperature on the behaviour of a non-quenched and tempered steel during hot forging.
Theoretical guidance for the process of hot forging, mold optimization and the control of microstructure properties should be effectively provided to promote the accuracy of the finite element method to simulate the forging process of non-quenched and tempered steel, On account of the hot forming behaviour was affected by many factors, the proper high temperature flow stress-strain model which can reflect micro-deformation mechanism is the foundation of accurate simulation [2].
ƒIn a variety of stress level, the relationship between flow stress and strain rate can be represented as Eq(7): (7) A is the structure factor, in units of s-1; α is stress level parameter, in units of MPa-1; and α = β / n.
According to the linear relationship the average value of hot deformation activation energy Q was obtained as 534.55KJ/mol, as well as the structure factor A was calculated as1.2903 × 1019s-1.
Therfore, proper process should be selected in compliance with material properties and to achieve the requirements of the parts

These requirements may involve long-term mechanical properties, early-age strength, toughness, volume stability and long-life in severe conditions.
Experimental studies on autogenous shrinkage have revealed that both the type of cement and w/c are influencing factors [31].
The evolution of the resistance against deformation, i.e. of the mechanical properties, is different for different types of cement and different mix compositions.
Not only the chemical composition, but also the fineness of the cement and the curing temperature determine how the microstructure of the system and the associated mechanical properties develop with progress of the hydration process.
Bentz: Influence of Shrinkage-Reducing Admixtures on Early-Age Properties of Cement Pastes.

Abstract: This research focuses on the development of low cost powder metallurgy (PM) Ti alloys suitable for application in PM thermomechanical processing with mechanical properties comparable to those of wrought Ti6Al4V alloy.
The higher YS and UTS are because of two factors: firstly, the severe deformation during thermomechanical processing results in extra strong interparticle cohesion; secondly, the comparatively high oxygen content of the starting Ti or Ti6Al4V HDH powders.
The physical and mechanical properties such as sintered density and tensile properties are presented and compared.
The tensile properties of the as sintered samples are shown in Fig. 3 as a comparison with the tensile properties of the further thermomechanically treated samples.
Further thermomechanical treatment by ODF and PCE did not improve the properties.

The bio-corrosion properties of the high pure magnesium in the Hank's solution were investigated in this paper, the results showed that high pure magnesium had a low corrosion rate and hydrogen release in Hank's solution, when the pH value of solution was controlled at 7.5, the corrosion rate was under 0.2mm/year, the production of hydrogen was about 0.15ml/cm2, and if the solution wasn't controlled on pH value, the corrosion rate was about 0.02 mm/year, production of hydrogen was about 0.1ml/cm 2 .
Today, with the advance of alloying technology and metal processing, the properties of magnesium and its alloys have been significantly improved.
The kinetic clotting time test is to determine the extent of the intrinsic clotting factors activated after the material contacting blood.
Our results indicated that the high purity magnesium has better thromboresistant property than 316L steel.
This low corrosion rate will not impact the mechanical integrity of implant magnesium materials and the production of hydrogen in the corrosion process is too tiny to affect the host tissue.

It is crucial to note that organic soil is not suitable for construction purposes due to its hazardous properties.
In the field of geopolymers, various factors such as the aluminosilicate source, the activating solution, and the curing environment, play pivotal roles in shaping the material's characteristics[11].
Among these factors, the Si/Al molar ratio of the aluminosilicate source stands out as a critical determinant, significantly influencing the mechanical strength and microstructure of geopolymers.
The physiochemical properties of organic soil are given in Table 1.ss Table 1.
Physiochemical properties of Organic soil.

RPC is an ultra-high-strength, high-ductility, low-porosity cementitious composite material with advanced mechanical and physical properties.
RPC technology can create materials that extend from those with traditional heterogeneous characteristics normally associated with concrete to more homogeneous materials that have isotropic properties and energy absorption capabilities that approach the characteristics of metals [1-5].
This paper investigates the factors which have influences on the strength of RPC.
Testing The compressive strength and flexural strength are measured according to GB/T50081-2002, "Standard for test methods of mechanical properties on ordinary concrete".
[10] HUANG Li-dong, XING Feng, DENG Liang-peng, and HUANG Pei-hong: Study on Factors Affecting the Strength of Reactive Powder Concrete, Journal of Shenzhen University Science and Engineering, 2004, 21(2), pp. 178-182(in Chinese).

So the performance of the filler zone directly affects the temperature of the outlet water.
Among the many affecting factors, such as filling method, filling height, filling depth ect, the cleanliness of the filler should not be underestimated.
It is imperative to study how fouling affects the filler’s heat and mass transfer performance.
Taking these factors, we can assume the following: firstly, the air flow is two-dimensional; secondly, the shear carrying when air sweeps over the water film can be ignored.
Once the filler layer is fouled, the heat and mass transfer performance is affected.

These elastic structures interact with the fluid dynamics, affecting recirculation zones and flow separation downstream of the BFS.
By investigating the influence of various parameters, such as the elasticity of the fin, their positioning, and their length, this study seeks to enhance comprehension of how these factors affect fluid flow rates and thermal behavior.
The fluid flowing within the conduit is the air, while the thermophysical properties are listed in Table 1.
Thermophysical properties of air and steel at 20°C [52].
In fact, the maximum displacement occurring just below the top of the fin is attributed to the interplay between fluid dynamics and the mechanical properties of the fin.