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Fine truing will make the number of micro-blades spreading on the grinding wheel surface of the same depth increase, and the equality of the altitude of the micro-blades on the wheel surface is good.
It not only solves the problem of dressing and sharpening of cast-iron bonded wheels, but also makes it possible to apply diamond and CBN wheels made of super fine abrasive, to 5nm in grain size, to accurate mirror grinding [1].
When the tool is fed continually, each Journal Title and Volume Number (to be inserted by the publisher) 269 point on the workpiece will be electrolyzed at different speed and the profile of the workpiece will be the same as that of the cathode little by little until the shape of the cathode is copied on the workpiece.
As grinding goes on, the grains and the oxide layer wear out.
ELID started e ELID stabilized Worn-out Abrasive Protrusion ELID cycle Journal Title and Volume Number (to be inserted by the publisher) 271 Table 1 ELID grinding results Surface roughness Materials Area [mm] Rmax [nm] Ra [nm] Grit Size [#] SC-Si � 40 30 5 8000 WC-Co � 20 10 3 4000 AL2O3-TiC 30×30 20 5 4000 Si3N4 20×50 30 5 4000 SiC 30×50 30 5 4000 G7 � 30 30 5 4000 Table 2 ELID Grinding Removal Rate Materials Grinding conditions SiC Si3N4 Grinding speed [m/min] 1200 1200 Feed rate [m/min] 20 20 Depth of cut [µm] 30 30 Width of cut [mm] 10 10 Grit size [#] 140 140 Removal rate [mm3/min] 6000 6000 Feasibility of Applying ELID to Ultra-precision Grinding for the Raceway of Ball Bearings Machining Process of the Ring Raceway of Ball Bearings.

In this paper, an in-depth analysis of existing cloud storage system architecture, functionality, and security applications on demand, to study and propose a number of cloud storage systems to ensure data security algorithms and programs, and designed a user-oriented cloud storage data security institutional framework.
Figure.2 Prototype system cloud computing environment Built using a small LAN to simulate the entire cloud environment, LAN hosts using 7, where 1 host as a client; a host as a cloud administrator, occasional pieces Euca2ools security Eucalyptus on that machine, complete the entire platform a host of cloud computing portal platforms, components and installation CLC Walrus on this host;; 1 cluster hosts used to manage and configure, install CC components and memory control components on this host; the control and management end of the two hosts as a node server, a mainframe computing services used to run a number of virtual machine instances, a desk used for storage; well as paper introduces a host of TCTP.
Figure.4 Search Service Performance Testing According to the position of the block in the file allocation for each sub-block number as the name of a table column file_ attribute_ cf adopted Cassandra's Super Column Family structure, which means that the label information of the user and the corresponding file and each file.
SaaS data protection subsystem CA DataGuarder design goals are based on decentralized information flow control thought marking and tracing data, to provide fine-grained data protection.
This deployment model based on the credibility of the work aaS platform provides fine-grained data security mechanisms for the upper SaaS services to achieve the end-user data isolation.

Tang et al [9] present that the improvement in hardness is attributed to the fine scale precipitation of an ordered compound (CrCu2Zr, Mg) and Cu4Zr phase is on the grain boundary.
When the specimens aged at 450˚C for 5 min, a large number of solute atoms precipitate out from the matrix (Fig. 2(a)), which can be identified as G.P zones.
When the specimens are aged for 4 h, a great number of Cr precipitates are observed in the matrix, as shown in the Fig. 2(b).
Since precipitation process is mainly diffusion process, the Avrami law can be used to describe this dynamic process: f=1-exp(-btn) (3) Where the b and n is constant. b depends on the temperature of phase transformation, composition of supersaturation solid solution and size of crystal grain. n depends on the type of phase transformation and nucleation location.
A large number of precipitates can be observed due to the high aging temperature in the initial stage of aging.

The literature review of the studies shows that it is possible to increase the strength, operation and thermal protective characteristics of building ceramics owning to the formation of the porous structure with the prevailing number of pores of 0.5-10 microns diameter, as well as the formation in the pore walls stable long-term compounds, micro-reinforcing the ceramic matrix.
The data are the consequence of the directed action of wollastonite as a micro-reinforcing component, in combination with the superplasticizer S-3, on the sintering of clay mass and the formation of the structure of the ceramic matrix with the porosity, redirected to decreasing the number of dangerous and reserve pores (by 40-43%) and to increasing the number of intermediate and safe pores (by 2-4%).
Chudakova, Modification of fine-grained concrete with micro- and nano-particles of schungite and titanium dioxide, Bulletin of BSTU. 2 (2010) 67-70
Kuzmin, Fine-grained concrete of composite binder, IOP Conf.

That is to say, using simple but interactive elements as well as finite number of unknowns to approximate the practical system with infinite number of unknowns Optimization is a technology that finds the optimal solution.
Since the bamboo shell was anisotropic material, both the tensile strength and compressive strength parallel to the grain were excellent.
The compressive strength parallel to grain of a double-layer bamboo with a thickness of 0.2mm was enhanced to about 30MPa and the tensile strength was enhanced to 80MPa after processed by the 502 glue.
The thickness of the shell was set to 3.5mm, the model mass equaled to the final volume subtracted the plate’s volume and then multiplied by its density. 1.4 Modeling and computing Taking the box section as example, detail steps were as follows: 1) Name the work file as ANSYS OPT1. 2) Define the material element as BEAM188 and SHELL63. 3) Define entity parameters TK=3.5mm. 4) Define material property: EI=1e4MPa, v=0.3. 5) Build geometry model (points, lines, surfaces). 6) Define variables A, B, C and their initial values. 7) Define the size and type of the section. 8) Mesh and define section. 9) Apply constraints and loads. 10) Solve and obtain results. 11)Extract parameters, sum the total volume, and obtain the maximal stress. 12) Build optimization file. 13) Define design variables A, B, C, D, E, F, G, state variable maximal stress element SEQV and target function VOLU. 14) Set the number of output 15) Run and solve 16) Extract the results.

It can be seen that the grain size of as-solid solution treated Y-containing alloy (Fig. 3b) is finer than that of Y-free alloy (Fig. 3a).
It suggests that the trace yttrium can effectively increase the nucleation number and inhibit the growth of precipitates.
Owing to its large atomic radius, yttrium distributes in the grain boundaries and defects such as Fig. 2 Variation of conductivity of the alloys with aging time and temperature (a) Cu-0.6Cr-0.15Zr-0.05Mg-0.02Si alloy (b)Cu-0.6Cr-0.15Zr-0.05Mg-0.02Si-0.05Y alloy (b) (a) (c) (d) Fig. 3 OM of alloys after rolling and then aging (a) Cu-0.6Cr-0.15Zr-0.05Mg-0.02Si alloy after solid solution treating (b) Cu-0.6Cr-0.15Zr-0.05Mg-0.02Si-0.05Y alloy after solid solution treating (c) Cu-0.6Cr-0.15Zr-0.05Mg-0.02Si alloy after 80% rolling+480˚C×8h aging (d) Cu-0.6Cr-0.15Zr-0.05Mg-0.02Si-0.05Y alloy after 80% rolling+480˚C×8h aging dislocations and blocks the short range diffusion tunnel of Cr and Zr atoms, whereas it lowers the diffusion rate of Cr and Zr in the copper and inhibits the growth of the precipitates such as Cr-rich and Zr-rich particles.
However, it is not clear yet that how yttrium addition can increase the nucleation number in Cu-Cr-Zr-Mg-Si alloy.
They aggregate gradually along some close-packed planes and then become the solute-rich zones, which results in the increasing of nucleation number of precipitates.

The Chemical composition and grain-size analysis of the high performance superfine mineral powder are presented in Tables 1 and 3, respectively.
Table 1 Chemical composition of the cement and superfine mineral powder % Chemical composition SiO2 CaO Al2O3 Fe2O3 MgO SO3 Alkali Content LOSS ∑ cement 24.30 52.51 8.85 2.53 4.26 2.28 0.48 3.79 99.20 mineral powder 35.06 28.51 19.86 3.31 8.21 0.99 - 1.6 97.54 Table 2 Mineral composition of cement % Mineral composition C2S C3S C3A C4AF Content 19.75 56.88 7.89 9.74 Table 3 Grain-size analysis of the high performance superfine mineral powder Cumulative percentage(%) <10 <25 <50 <75 <90 Particlesize(µm) 1.228 3.070 8.670 18.000 26.780 Chloride ions erosion tests Mixing proportions and performance parameters.
Table 4 Mixing proportions of the testing concrete Number Cement (kg/m3) Mineral powder (kg/m3) Coarse aggregate (kg/m3) Fine aggregate (kg/m3) Water (kg/m3) Pumping agent (kg/m3) w/c A1 340 130 1050 700 172 9.4 0.38 A2 320 170 1050 700 170 9.8 0.36 A3 300 190 1050 700 166 9.8 0.35 A4 280 220 1050 700 164 10.0 0.34 N.B Water in the pumping agent is measured as 6 kg Table 5 Performance of the fresh concrete Number Air content (%) Initial slump (mm) Initial slump flow (mm) 1h slump (mm) 1h slump flow (mm) Compressive strength (Mpa) 3d 7d 28d A1 5.2 220 520 180 390 23.2 33.6 46.2 A2 5.3 230 540 185 410 23.0 34.2 50.3 A3 5.3 235 550 190 420 22.8 34.9 51.6 A4 5.4 240 580 200 450 22.7 35.8 53.8 Results of chloride ions erosion tests.
Table 6 Mixing proportions of sulfate resistance concrete Number Cement /(kg/m3) Mineral powder /(kg/m3) Coarse aggregate (kg/m3) Fine aggregate (kg/m3) Water (kg/m3) Pumping agent /(kg/m3) w/c Superpla -sticizer Air entraining agent K1 500 0 1050 700 170 1.25 10.00 0.34 A4 280 220 1050 700 170 1.25 10.00 0.34 Pag1.

This machining method involves bringing the workpiece into surface contact with a wheel with a large number of effective cutting edges.
However, it also presents a number of problems: it is difficult to supply the machining fluid to the cutting point and loading occurs easily; the depth of cut is shallow, the length of cut is long, and the cutting edges tend to dull; the dynamic pressure of the machining fluid causes the workpiece to float, and in cases of low machining pressure, machining does not advance; and the workpiece is often scratched.
The supply of machining fluid has been improved by a number of methods, including the design of multiple grooves on the wheel surface, and various measures have been applied to reduce the effects of dynamic Fig. 1 Principle of plane honing pressure [4].
In our experiment, however, in order to minimize vibration from the machining system, damage to the workpiece, uneven wear of the wheel, and release of abrasive grains, an ultra-precision plane honing machine was developed and manufactured in which the wheel rotation axis and the workpiece rotation axis were supported by high-rigidity hydrostatic oil bearings.
This indicates that material is removed by abrasive grains in ductile micro-cutting mode.

PREN (pitting resistance equivalent number) of this steel is (13 – 16.5).
On-site measurement with portable X-ray detector was limited only to elements with atomic number higher then 22 (Ti).
Particles of δ ferrite occurring principally along the boundaries of the prior austenite grains correlate with the direction of solidification of the cast steel (Fig. 9).
The segregation and inhomogenity of chemical composition typical for grain boundaries may cause the weakening of passivation effect on the steel surface.
[6] Calculation of pitting resistance equivalent numbers (PREN), information on http://www.bssa.org.uk/topics.php?

The average surface area of the nodules was calculated by dividing the total surface area of all particles per unit volume (SV) by the volumetric number of particles (grain density NV):
These parameters for Eq. (5) were calculated by the Saltykov’s secant method for SV , (6) and by the Saltykov’s method of invers diameter for NV , (7) where: PL – the number of intersections of the surface of graphite nodules per unit length of the secants, F – total surface area of the analyzed metallographic sections, di – diameters of the 2D sections i.
Cumulative distribution function of grain nodules in the sample I and II obtained by Eq. 2 (a) and volumetric cumulative number of the spherical graphite particles (b).