Xibin Yang^*, Rui Li^†,‡, Jianfeng Zhu^*, Daxi Xiong^*

Molecular & Cellular Biomechanics, Vol.9, No.4, pp. 285-294, 2012, DOI:10.3970/mcb.2012.009.285

Abstract A new type of optocoupler applied to medical lighting system is proposed, and the principle, Etendue and design process is introduced. With the help of Tracrpro, modeling and simulation of the optocoupler is conducted and the parameters are optimized. Analysis of factors affecting the energy coupling efficiency is done. With a view towards the development of Ultra High Brightness Light Emitting Diodes (UHB-LEDs), which play an important role a new sources of lighting in various biomedical devices, including those used in diagnosis and treatment, a series of simulations are executed and a variety of solutions More >

Ying Xu¹, Shengping Shen^1,2

CMC-Computers, Materials & Continua, Vol.28, No.1, pp. 81-96, 2012, DOI:10.3970/cmc.2012.028.081

Abstract This paper considers the surface effect through the surface and bulk electric Gibbs free energy. The analytical expressions are derived for the effective elastic, dielectric and piezoelectric modulus for nano-structural elements in electromechanical coupling problems. Numerical examples for PZT are given to illustrate the size effects on the electromechanical properties of nano-particles, nano-wires and nano-films quantitatively. The solution shows that the electromechanical properties of piezoelectric nano-material are size-dependent but the size effects on the elastic property and dielectric property are different. More >

V. C. Loukopoulos¹, G. C. Bourantas²

CMES-Computer Modeling in Engineering & Sciences, Vol.88, No.6, pp. 531-558, 2012, DOI:10.3970/cmes.2012.088.531

Abstract Meshless Local Petrov-Galerkin (MLPG) approach is used for the solution of the Navier-Stokes and energy equations. More specific as a special case we apply the MLPG6 approach. In the MLPG6 method, the test function is chosen to be the same as the trial function (Galerkin method). The MLPG local weak form is written over a local sub-domain which is completely independent from the trial or test functions. The sizes of nodal trial and test function domains, as well as the size of the local sub-domain over which the local weak-form is considered, can be arbitrary.… More >

P.P. Prochazka¹, M.J. Valek¹

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.3, pp. 207-224, 2012, DOI:10.3970/cmes.2012.087.207

Abstract In classical theories of homogenization and localization of composites the effect of shape of inclusions is not taken into account. This is probably done because of very small fibers in classical composites based on epoxy matrix. Applying more precise theoretical and numerical tools appears that the classical theories desire corrections in this direction. Today many types of materials their fiber are much bigger and with various material properties are used and behave as typical composites. They enable producers to create the fiber cross-sections and model them in various shapes, so that it is meaningful to More >

Miaoxia Xie¹, Yueming Li¹, Hualing Chen^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.85, No.1, pp. 65-78, 2012, DOI:10.3970/cmes.2012.085.065

Abstract Energy finite element method(EFEM) is a promising method to solve high-frequency vibro-acoustic problem. Energy boundary element method (EBEM) is an effective way to compute high-frequency sound radiation in the unbounded medium. Vibro-acoustic coupling of cavity structure in anechoic chamber includes both the interior acoustic field and unbounded exterior acoustic field. In order to predict this kind of high-frequency vibro-acoustic coupling problem in anechoic chamber, an approach combined EFEM and EBEM is developed in this paper. As a numerical example, the approach is applied to solve the high-frequency vibro-acoustic coupling response of a cubic cavity structure More >

Seyfolah Saedodin, M.S. Motaghedi Barforoush, Mohsen Torabi^*

Frontiers in Heat and Mass Transfer, Vol.2, No.4, pp. 1-4, 2011, DOI:10.5098/hmt.v2.4.4001

Abstract In this paper, a simplifying approach for calculating the radiant energy is achieved using the concept of net radiation heat transfer and provides an easy way for solving a variety of situations. This method has been applied to calculate the net radiation heat transfer between two long concentric semi-cylinders. Then this method used to calculate reduction heat transfer when radiation shields with temperature-dependent emissivity applied between these objects. Moreover, using this method the percentage reduction in heat transfer between two surfaces was calculated. The findings reveal that, one radiation shield with lower emissivity can reduce More >

Q.X. Wu^a, Y.L. He^b, T.S. Zhao^a,b,*

Frontiers in Heat and Mass Transfer, Vol.2, No.3, pp. 1-14, 2011, DOI:10.5098/hmt.v2.3.2001

Abstract Running direct methanol fuel cells (DMFC) with concentrated fuel is desirable to maximize the specific energy of the fuel cell system and to improve the performance by mitigating the water flooding problem associated with diluted methanol operation. This article provides a comprehensive review of recent advances in understanding mass transport phenomena in DMFCs operating with concentrated fuel. The review starts with elaborating the key issues of mass transport of reactants and products associated with highly-concentrated methanol operation, followed by summarizing and discussing past experimental and numerical investigations into the effects of the membrane electrode assembly More >

Elena Jakubikova, David N. Bowman

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 127-128, 2011, DOI:10.3970/icces.2011.019.127

Abstract The Sun is an abundant source of energy capable of meeting all our energy needs if properly harvested. Some of the ways to utilize solar energy is conversion of sunlight to electricity via photovoltaic solar cells or to chemical fuels via photocatalytic synthetic cells. Many of such systems are designed around a photoactive molecule (a chromophore) anchored to a semiconductor. The conversion of sunlight to electricity occurs via absorption of light by the chromophore, followed by the interfacial electron transfer between the chromophore and semiconductor. We investigate the use of Fe(II)-polypyridine compounds as chromophores in More >

G. Seifert, S. Leoni, M. Baldoni

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.3, pp. 69-70, 2011, DOI:10.3970/icces.2011.017.069

Abstract Energy storage is particular important for advanced fuel-efficient vehicles and mobile applications, rechargeable batteries play a key role for such applications. Lithium-ion batteries are today the leading energy storage systems. However, the cathode materials remain insufficient for the use of lithium-ion batteries. To improve this drawback, cathode materials has to be developed further. Therefore, today, most research is focused on the cathode material, and a precise knowledge of the diffusion/transport behaviour of lithium cations inside battery-cathode materials is critical for improving energy density, material properties, and for estimating the impact of chemical substitution. Computer simulations… More >

Bo Mi Lee, In-Ho Kim, Hyung-Jo Jung

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.1, pp. 19-20, 2011, DOI:10.3970/icces.2011.019.019

Abstract Vibration energy harvesting, which converts ambient vibration energy into electrical energy, has been an attractive energy scavenging technique to power wireless sensors or low power devices. Even though vibration energy harvesting has drawbacks which are relatively low harvested power and narrow bandwidth, vibration energy scavenging is one of the promising alternative power techniques in that MEMS techniques can be applied to microminiaturize the system. Therefore, many researches have been done to overcome these problems(Lee et al.2010). This paper presents improvement efficiency on piezoelectric vibration energy harvesting device to surmount issues of vibration energy harvesting. Numerical More >