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Department of Mechanical Engineering, Salman bin Abdulaziz University, Alkharj, KSA.
Considering the Jacobian matrix of a robot manipulator, the condition number is an error amplifying factor of actuators, so affecting the accuracy of the Cartesian velocity of the gripper.
In order to achieve a global property of the manipulator, the global conditioning index (CGI) is used.
In order to achieve a global property of the manipulator, the following adaptation is used.
Dou, Optimum design of a 3-RRR planar parallel manipulators, Journal of Mechanical Engineering Science, 224 (2010) 411-418

According to this, one of the most important factors is environment pH.
It has strong effect on the kinetics of the anodic reaction and therefore properties of passive layer.
By decreasing pH the passive layer tends to dissolution and loses its protective properties [3].
It is known that the environment, the chemical composition, heat treatment and the microstructure can be affecting the pitting potential [19].
Frankel, Pitting corrosion of metals a review of the critical factors, J.

If the outburst happens, the results of it will affect the normal mining process, destroy the equipment, threaten the worker’s life, etc..
In the paper, we think that the study on the physical and mechanical properties of coal and rock with and without gas is the primary task to resolve the outburst problem in the mine.
In order to study the creep properties of rock-liked materials, laboratory experiments are the main methods to investigate time-dependent mechanical properties of rocks through long-term testing and observations, strict control of the testing conditions and elimination of the effects of secondary factors in time-dependency [5-8].
Analyzing the previous experimental results of coal creep properties and considering the shortcoming of General Kelvin model, one nonlinear damage creep model of coal is founded based on the general Kelvin model.
As the general Kelvin model can describe the elastic and viscous deformation perfectly, so in the following, we choose the Kelvin model as the basic model to describe the creep properties of coal.

Due to the exceptional properties of these superalloys their machining becomes very difficult and time-consuming; They damage the cutting tool, and excessive use of lubricants eventually affect the material handling and cost.
Introduction Nimonic and other nickel-based alloys are promising materials for use in nuclear and gas power plants for turbine components due to their exceptional mechanical and thermal properties [1].
The advanced properties of these Nickel-based superalloys make them very difficult to machine, and therefore, their machining costs are sometimes unbearable [2].
The solid lubrication technique effectively increases the machinability of the Nimonic 90 superalloy; however, future work needs to be done in this domain such that the lubricative material, method, and economic factors are equally considered.
Wood, “Tribological performance of surface texturing in mechanical applications—a review,” Surf Topogr, vol. 8, no. 4, p. 043001, Dec. 2020

Together with excellent mechanical and corrosion properties at high temperatures, such characteristics are very attractive for applications in the aeronautical, aerospace and automotive industries.
However, the current high selling price, due to high costs of production and raw materials and the need of very specific equipment, are limitative factors for further applications.
The comparison of such profiles with hardness ones gives insight in the role of the oxygen concentration in the properties of the alloy and in the choice of the most suitable materials for TiAl production Introduction During the last decade several intermetallic alloy systems have been identified as potential candidate materials for applications at high temperatures.
The best compromise between high temperature properties and room temperature ductility, is achieved with a two-phase microstructure (�2 + �), for a volume ratio �2 /� between 5 and 15%.
As a consequence, chemical composition gradients can be found, at room temperature, from the surface to the inside of castings, leading to significant changes in their mechanical and technological properties, like a surface “hard case”, usually called “alpha-case”.

Petersen et al. [3] have analyzed product development using firm dependent decisions factors such as product quality and process selection and a SC design factor.
They differ in formability, weldability, corrosion resistance, and hardness properties.
The major factors that influence AA process selections are classified into three categories: material factors (mechanical and physical properties, alloy specification), geometry factors (part shape, envelope size, weight, dimensional tolerance, surface finish, secondary operations) and production factors (lead time, production volume and rate) [11].
These factors can be viewed as a forward design factors as it focuses on SC forward material flow activities.
In a context of a CLSC, it is necessary to consolidate these factors with the reverse logistics design constraints.

Physical and mechanical property of the material was a key basis to determine the slope stability of waste pile.
Different material composition and diameter combination are all key factors that influence slope stability of waste pile.
As far as slope stability of the waste pile is concerned, difference of gradation and strain history are key factors of influence on failure.
References [1] Guanglong Huang, Jian Zhou, Xiaonan Gong: Stress-strain and Shear Strength Properties of Rock and Soil Materials of Waste Pile in Open Pit Mines.
[9] Jingping Wu, Yao Chu, Zhigang Lou: Influence of Particle Breakage on Deformation and Strength Properties of Calcareous Sands.

Microwave Absorbing Properties of Flaky Fe-Si-Al Alloy Powder-Rubber Composites Kyung-Sub Lee1,a , Yeo-Chun Yun2,b , In-Bum Jeong 3,c , and Sung-Soo Kim 4,d 1-3 R&D Center, Changsung Corporation, 11-9, Namdong Industrial Area, Namdong-ku, Incheon, Korea 4 Department of Materials Engineering, Chungbuk National University, heungduk-ku, Gaesin-dong 12, Cheongju 361-763, Korea a kslee121@changsung.com, b ycyun@changsung.com, c ibjeong@changsung.com, d sskim@chungbuk.ac.kr Keywords: magnetic composite, absorber, reflection loss, permeability, permittivity, flake Abstract.
The frequency profile of complex permeability (μr) and permittivity (εr) and their relationship with microwave absorbing properties are investigated in soft magnetic metal-polymer composite materials.
Thin flake Fe-Si-Al particles were prepared by mechanical forging of spherical powders using an attrition mill.
It is evident that the permittivity of magnetic composite was strongly affected by the thickness of flaky powder and aspect ratio variation as shown in figures 3 and 4.
This is believed that the decrease of the permittivity and density of the flexible sheets manufactured in calendaring process may be factors responsible for the shift to high frequency of maximum reflection loss peak.

Materials are differ in their mechanical and physical properties, behavior under different conditions of external influence.
Creating a mathematical model to describe the deformation of low alloy high strength steel is impossible without taking into account the physical and mechanical properties of the material.
In the literature, the properties of HSLA steels are inadequate, it’s need further research.
It is therefore necessary to study changes in the plastic properties of steel on the degree of deformation and external factors in the conditions of metallurgical production of continuous cold rolling mill.
The advantage of the engineered algorithm (determining hardening curve of the steel by the theoretical model) is the account of the main factors (the total degree of preceding deformation, strip temperature, strain rate) that affect on the level of yield strength in the process of cold rolling.

The nature of an electrolyte used for aluminium anodising is a key factor which determines the type of oxides grown on the surface [1].
It was reported that some mixed acid and organic acid as anodising electrolytes can decrease the film dissolution rate, then increase the film formation efficiency and improve the film properties [6].
Since the AAO membrane characteristic were affected by anodising voltage, the controlling of the anodising voltage is essential in order to gain desired characteristic of AAO membrane for specific purpose [9].
Some formation factors affecting the dissolution behaviour of anodic oxide films on aluminum in H3PO4.
International Journal of Mechanical and Materials Engineering (IJMME), Vol. 5, No. 1, 53-58