• Journal of Information Processing Systems
• /
• v.16 no.2
• /
• pp.460-477
• /
• 2020

As one of the most significant challenges in the virtual data center, the virtual data center embedding has attracted extensive attention from researchers. The existing research works mainly focus on how to design algorithms to increase operating revenue. However, they ignore the energy consumption issue of the physical data center in virtual data center embedding. In this paper, we focus on studying the energy-aware virtual data center embedding problem. Specifically, we first propose an energy consumption model. It includes the energy consumption models of the virtual machine node and the virtual switch node, aiming to quantitatively measure the energy consumption in virtual data center embedding. Based on such a model, we propose two algorithms regarding virtual data center embedding: one is heuristic, and the other is based on particle swarm optimization. The second algorithm provides a better solution to virtual data center embedding by leveraging the evolution process of particle swarm optimization. Finally, experiment results show that our proposed algorithms can effectively save energy while guaranteeing the embedding success rate.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.4 no.3
• /
• pp.39-44
• /
• 2005

With the development of high speed and accuracy machining, the micro-chips are formed in the machining process and broken particles are circulated with the cutting fluid. The surface roughness and accuracy of part are deteriorated because the metal particles included in the cutting fluid are embedded on machined surface. In this study, the influences of particles for the machined surface according to filtering degrees are evaluated and the embedding mechanism is suggested.

• Proceedings of the KSME Conference
• /
• 2003.11a
• /
• pp.1157-1162
• /
• 2003

Behavior of aluminum alloy embedding a particle was investigated at room temperature under ECAP. Finite element analysis by using ABAQUS shows that ECAP is a useful tool for eliminating residual porosity in the specimen, and much more effective under friction condition. The simulation, however, shows considerably low density distributions for matrix near a particle at which rich defects may occur during severe deformation. Finite element results of effective strains and deformed shapes for matrix with a particle were compared with theoretical calculations under simple shear stress. Also, based on the distribution of the maximum principal stress in the specimen, Weibull fracture probability was obtained for particle sizes and particle-coating layer materials. The probability was useful to predict the trend of more susceptible failure of a brittle coating layer than a particle without an interphase in metal matrix composites.

• Korean Chemical Engineering Research
• /
• v.46 no.1
• /
• pp.137-141
• /
• 2008

Copolymerization of ethylene and ${\alpha}$-olefin using $rac-Et[Ind]_2ZrCl_2/MAO$ catalyst embedded onto polysty-rene was examined. The embedded catalyst was prepared by polymerizing a small amount of styrene with $rac-Et[Ind]_2ZrCl_2$. The catalytic activities of the embedded catalyst were higher than those of the homogeneous catalystregardless of comonomer type and the characteristic of the active sites of the embedded catalyst was not affected duringthe embedding process. Based on the DSC and NMR analyses of the produced copolymers, it was thought that theembedded catalyst had similar or slightly better comonomer incorporation ability. Furthermore, the copolymers produced by the embedded catalyst had higher bulk densities and better particle morphology than those by the homogeneous catalyst.

• Journal of the Semiconductor & Display Technology
• /
• v.16 no.4
• /
• pp.36-40
• /
• 2017

With an attempt to enhance the visibility of laser beam, we have investigated a black matrix with scattering particles by ray tracing simulations. As the scattering particle density is increased, the detected power by the receiver is increased, thereby enhancing the visibility. In reality, the visibility is reduced with increasing incident angle (away from the normal incidence) of laser beam, a phenomenon also observed by ray tracing simulations. It is due to the fact that the mean path is increased within a highly absorptive BM layer or a smaller number of rays hit the BM area when the incident angle is high. Embedding a number of scattering particles into BM may bring in crosstalk among pixels. However, it is negligible because scattered rays inside highly absorptive BM are re-scattered due to the high scattering particle density, decreasing the power of scattered rays into the active areas.

• Proceedings of the KSME Conference
• /
• 2008.11a
• /
• pp.175-180
• /
• 2008

Thermoelectric materials convert temperature difference to electric power for power generation and vice versa for refrigeration. Recent advances in enhancing the thermoelectric figure-of-merit shed light on efficient power generation from the waste heat available in industries and vehicles. Nanoscale phenomena with both nanoscale constituent-embedded bulk samples and nanoscale materials proving enhanced thermoelectric performance have been widely reviewed. Bulk materials of crystal-orientation and nano-structured particle embedding seem to promise a higher thermoelectric figure-of-merit and an effective power generation application. As a preliminary study, Si-Ge nanocomposite was prepared with spark plasma sintering method and its properties were examined.

• Journal of the Korean institute of surface engineering
• /
• v.41 no.6
• /
• pp.255-263
• /
• 2008

Generally, deposition mechanism of diamond particle is mainly embedding effect in the kinetic spray process. Accordingly, in spite of high cost, helium gas was employed as process gas to get high diamond fraction in the composite coating. In this study, the deposition behavior of bronze/diamond by kinetic spray process was compared using different process gas (helium and nitrogen). Bare (mean size of $5{\mu}m$, $20{\mu}m$) and nickel coated diamond (mean size of $26{\mu}m$) were deposited on Al 6061-T6 substrate with fixed process temperature and pressure. For comparison with experimental results, plastic deformation behavior of nickel layer was simulated by finite element analysis (using ABAQUS/Explicit 6.7-2). The size, broken ratio, and fraction of diamond in the composite coating were analyzed through scanning electron microscopy and image analysis method. The uniform distribution and deposition efficiency of diamond particles in the coating layer could be achieved by tailoring the physical properties of the feedstock.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.23 no.6 s.165
• /
• pp.968-978
• /
• 1999

The effective elastic properties of materials containing spherical inclusions were calculated by the elastic wave scattering theory. In the formulation additional scattering fields by the presence of random multiple scatterers that affects the effective properties were found by the single scattering approximation. In calculating the scattering fields the ensemble average on the displacements and strains inside the scatterer was found from the static approximation at long wavelength limit. The displacements were assumed to be equal to the incident field, while the strains were calculated by Eshelby's equivalent inclusion principle on the single inclusion problem. Four different models were considered and they reflected different degrees of multiple scattering effects based on the approximation introduced in the process of embedding the inclusion in the matrix. The expressions for the effective elastic constants were given in each model, and their relations to the results obtained from other scattering theory and elasticity theory were discussed. The theoretical predictions were compared with experimental results on the epoxy matrix composites containing tungsten particles of different sizes and volume fractions

• Composites Research
• /
• v.27 no.3
• /
• pp.83-89
• /
• 2014

The purpose of this study is to improve the strength and thermal conductivity of polybutylene terephthalate (PBT) by embedding various additives. Specimens were prepared using PBT pellets embedded with glass fibers (GF) and boron nitride (BN) powders. The test results showed that tensile strength decreased, and thermal conductivity increased with increasing BN contents. with thermal shock cycles conducted, unfilled PBT showed a considerable decrease in failure strain and strength, whereas strength and thermal conductivity of glass fiber and BN particle-embedded PBT had little differeces. With increasing BN, the thermal conductivity of PBT composites was highly improved.

• Geomechanics and Engineering
• /
• v.13 no.6
• /
• pp.1027-1044
• /
• 2017

Membrane penetration is the most important factor influencing the measurement of volume change for triaxial consolidated-drained shear test for coarse-grained soil. The effective pressure p, average particle size $d_{50}$, thickness $t_m$ and elastic modulus $E_m$ of membrane, contact area between membrane and soil $A_m$ as well as the initial void ratio e are the major factors influencing membrane penetration. According to the membrane deformation model given by Kramer and Sivaneswaran, an analytical solution of the membrane penetration considering the initial void ratio is deduced using the energy conservation law. The basic equations from theory of plates and shells and the elastic mechanics are employed during the derivation. To verify the presented solution, isotropic consolidation tests of a coarse-grained soil are performed by using the method of embedding different diameter of iron rods in the triaxial samples, and volume changes due to membrane penetration are obtained. The predictions from presented solution and previous analytical solutions are compared with the test results. It is found that the prediction from presented analytical solution agrees well with the test results.