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Nassr1,a and Wael Khair-Eldeen2,b 1Department of Civil Engineering, Assiut University, Assiut, 71516, Egypt 2Department of Mechanical Engineering, Assiut University, Assiut, 71516, Egypt aamrnassr@aun.edu.eg, bwaelmk@ittu.org Keywords: anchors, concrete, damage, dynamics, impact, strain rate, waves.
The ultimate load at splitting failure of an anchorage is affected by several factors such as the material properties of the concrete (concrete compressive strength); the size of the activated fracture surface (distances to the edges of the member or spacing in anchor groups); and the geometrical parameters of the anchors (anchor diameter and/or its embedment depth) [1].
It was found that the variation of the concrete strengths affected the loading capacity of the anchors by a maximum of 25%.

Fan1 1College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China, 210016 2College of Engineering, Nanjing Agricultural University, Nanjing, China, 210031 ashh@nuaa.edu.cn Keywords: Solid lubrication, Ti-6Al-4V, Grinding temperature, Microstructure Abstract.
The most influential factors affecting the grinding temperature were studied by conducting the experiments.
Microstructure of the ground surface layer.The microstructure of the ground surface layer is essential to the service property of the workpiece due to the distortion of crystal lattice during the plastic deformation of the surface layer under the grinding force.
The similitude of the microstructure of the surface layer with the mother material indicates that the lubricating property of the graphite and HBN are effective in reducing the frictional forces at the wheel-workpiece interface and the deformation of the surface layer of the workpiece.

In this paper, a stable and controllable mechanical device was designed and its reliability was tested and verified by theory design, underwater experiment and the finite element analysis.
And cracks would occur around the holes because of stress concentration phenomenon in the drilling process and there were inestimable factors affecting the piston cavity’s pressure ability.
The three-dimensional entity model with PVC materials properties was built in Pro/E software in the paper and the stress and strain of piston cavity could be analyzed [6,7] using powerful ANSYS finite element analysis function.

Placement Optimization for Thermal Performance of Embedded Power Chip Microwave Modules Using BP-GA Sheng Zhanga Zhaohua Wub Hongyan Huangc Pin Chend Tangwen Bie School of Mechanical & Electrical Engineering, Guilin University of Electronic Technology, Guilin, China 541004 aguxing916@126.com, bemezdj@guet.edu.cn, chhywangyi@163.com Keywords: Thermal Analysis, BP Algorithm Network, Genetic Algorithm, Microwave Modules, Optimization Design.
Introduction Temperature is the key factors which affect the working reliability of electronic devices.
The embedded-chips of components are the main source of heat, the position of the chip directly affects the distribution of the temperature field, the unreasonable layout of naked chip will lead to high temperature gradient and temperature in the internal and external microwave modules, and then reduce the reliability and performance of the microwave modules, so in the stage of placement optimization design for thermal performance in embedded high power multichip modules, using computer to simulate the temperature after placement is very necessary.
ALL materials, packaging body sizes and corresponding material properties are shown in table 1.

Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to examine thermal properties while the crystallinity was investigated by X-ray diffraction (XRD).
But recently, PLA has been focused on packaging application where PLA has to have suitable mechanical and physical properties accompanied by high molecular weight.
Thermal properties were characterized by differential scanning calorimeter (DSC, DSC 204 F1 Phoenix) and thermogravimetric analyzer (TGA, TGA/SDTA 851e).
(a) Fig 1 : 1H-NMR spectra of (a) succinic anhydride (b) hydroxylated prepolymer (c) chain-extended PLA Physical properties.
However, amount of succinic anhydride was not the only effective factor to increase molecular weight of PLA, when molar ratio between hydroxylated prepolymer and succinic anhydride was increased from 1:1 to 1:5, the increament of molecular weight of chain-extended PLA was slow, approximately 47% of weight increasing was obtained, implying that other factors such as reaction temperature and time should be considered.

Cotton is a hydrofilic textile fiber and, for this reason, it changes its properties according to the environment changes.
Moisture and Temperature are the two most important factors that lead a cotton Spinning sector and influence its quality.
Those two properties can change the entire Spinning process.
The humidity and the temperature are very important factors in a textile industry.
It may be seen through these values that even with this slight modifications, there was not major changes in the medium final result, therefore, it may be concluded temperature and humidity alterations have not affected considerably the count.

The main objective of the present work involved the study of the inhibitive properties of natural product as spearmint plant extract as a safety and an environmentally friendly corrosion inhibitor for low carbon steel in (3.5% NaCl) solution.
The effectiveness, or corrosion inhibition efficiency of a corrosion inhibitors is a function of many factors including but not limited to: fluid composition, quantity of water, and flow regime.
Where chemical analysis was performed using a spectral analysis of metals in the General Company for Mechanical Industries in Alexandria.
Table (1): Illustrates the percentages of the chemical composition of the carbon steel models used in research C % V % Ni % Mn % Fe % Rem. 0.25 0.19 1.45 97.17 Sample Preparation.Specimens were prepared as follows: 1- Sample Preparation. 2- Drying and washing sample . 3- Mechanical preparation of sample (polishing, grinding and cutting).
All of these compounds have properties of inhibition and this is consistent with the findings of other researchers.

The mechanical properties of the CFRP laminate are obtained from the standard coupon tests [2] and the here adopted mechanical properties of Matrix and Fibers are summarized in Tab. 1.
Fig.1 : Corner radius variation of the columns Table 1: Mechanical properties of CFRP Mechanical properties Fibers Matrix Modulus of elasticity [MPa] 211000 3000 Poisson’s ratio - 0.25 Compressive Strength [MPa] - 88.0 Tensile Strength [MPa] 4205 78.0 Table 2: Mechanical properties of concrete Mechanical properties C30 Modulus of elasticity Ecm [MPa] 29500 Poisson’s ratio 0.2 Compressive Strength [MPa] 30 Tensile Strength [MPa] 3 Fracture energy [J/m2] 90 In the first step of the study the parameters of the microplane model are calibrated for concrete and matrix.
As specified in [23] the concrete microplane parameters are set to correctly reproduce the macroscopic mechanical properties, minimizing the error between experimental and numerical stress-strain relationships in the case of unconfined concrete.
The concrete composition assumed for the numerical simulation of R75 is schematized in Fig. 11: Fig.11 : Concrete mesostructure:a) aggregates; b) mortar matrix; c) concrete Material properties and FE model The mechanical properties of CFRP used in the analysis are summarized in Tab. 1.
In Tab. 5  are summarized macroscopic properties of mortar matrix also used in the numerical study.

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.

Finite Element Analysis of the Pressing Screw in Screw Press Nanhui Yua, Shilong Li, Dewen Liu School of Mechanical Engineering, Wuhan Polytechnic University, Wuhan, 430023, China ananhui_yu@hotmail.com Keywords: Screw Press; Pressing Screw; Finite Element Analysis Abstract.
The construction of screw press is important, which directly affects the quantity and quality of produced oil [4].
So the analysis is made to each pressing screw respectively, meanwhile, it needs to consider the loads from mechanical conversion.
(a) No.4 pressing screw (b) No.7 pressing screw Fig. 2 Three-dimensional models of pressing screws According to the structure characteristics and load conditions of the pressing screw, Solid92 type element is selected to mesh its three-dimensional entity model, and 40Cr hardened and tempered steel is adopted as its material which has good comprehensive mechanical properties, the resulting finite element model is presented in Fig. 3.
In this paper, we only consider three major loads, that is, axial force, radial force and circumference force, but not include a number of other factors in the actual conditions.