R.D. Phillips¹, M.S. Hossain¹, L.T. Watson^1,2, R.H. Wynne³, Naren Ramakrishnan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.97, No.2, pp. 175-197, 2014, DOI:10.3970/cmes.2014.097.175

Abstract Clusters, typically mined by modeling locality of attribute spaces, are often evaluated for their ability to demonstrate ‘enrichment’ of categorical features. A cluster enrichment procedure evaluates the membership of a cluster for significant representation in predefined categories of interest. While classical enrichment procedures assume a hard clustering definition, this paper introduces a new statistical test that computes enrichments for soft clusters. Application of the new test to several scientific datasets is given. More >

Kai Wang¹, Guojian Li¹, Qiang Wang^1,2, Huimin Wang¹, Jiaojiao Du¹, Jicheng He¹

CMC-Computers, Materials & Continua, Vol.38, No.2, pp. 79-89, 2013, DOI:10.3970/cmc.2013.038.079

Abstract Study on the behaviors of the melting and coalescence of clusters in atomic scale may create new structure at nanoscale, which is a very important research field. The structural evolutions of clusters Cu₃₂₁, Co₃₂₁, and Ni₃₂₁ during their melting and coalescence processes were studied using molecular dynamics simulation with a general embedded atom method in this paper. It was found that the geometries of Cu₃₂₁ and Co₃₂₁ transformed to icosahedron from fcc near their melting points, which leads to the increase of their melting points. Concerning the coalescence, it was found that Cu atoms easily formed a coating More >

Guojian Li¹, Qiang Wang¹, Yongze Cao¹, Kai Wang¹, Jiaojiao Du¹, Jicheng He¹

CMC-Computers, Materials & Continua, Vol.30, No.3, pp. 195-206, 2012, DOI:10.3970/cmc.2012.030.195

Abstract This paper studies the influence of Ag atomic segregation on the structural evolutions of the mixed (PdAg)₃₀₉ clusters during the heating processes by using molecular dynamics with a general embedded atom method. The results show that the Ag atomic segregation makes the cluster exhibit a segregate-melting stage in which the energy does not monotonic increase with the increase of temperature. In this stage, the cluster first transforms to form a disorder structure from the initial icosahedron and then a decahedron. By comparing with the cases in the pure Pd₃₀₉, Ag₃₀₉, and core-shell (PdAg)₃₀₉, it is found that More >

J.E. Lee¹and S.J. Kim²

CMES-Computer Modeling in Engineering & Sciences, Vol.86, No.2, pp. 93-112, 2012, DOI:10.3970/cmes.2012.086.093

Abstract As the option trading nowadays has become popular, it is important to simulate efficiently large amounts of option pricings. The purpose of this paper is to show valuations of large amount of options, using network distribute computing resources. We valuated 108 options simultaneously on the self-made cluster computer system which is very inexpensive, compared to the supercomputer or the GPU adopting system. For the numerical valuations of options, we developed the option pricing software to solve the Black-Scholes partial differential equation by the finite element method. This yielded accurate values of options and the Greeks More >

Guojian Li, Qiang Wang, Yongze Cao, Jiaojiao Du, Jicheng He

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 119-120, 2011, DOI:10.3970/icces.2011.019.119

Abstract This paper studies the size-dependent freezing of Co, Co-Ni, and Co-Cu clusters by using molecular dynamics with a general embedded atom method. There is size effect occurs in these three types of clusters. The clusters with large sizes always freeze to form their bulk-like structures. However, the frozen structures for small sizes are generally related to their compositions. The icosahedral clusters are formed for Co clusters (for 3.2 nm diameter) and also for Co-Ni clusters but at a larger size range (for 4.08 nm). Upon Co-Cu clusters, decohedral structure is obtained for small size (for More >

Cheng-Hung San¹, Chuang-Pin Chiu¹, Che-Wun Hong^1,2

CMC-Computers, Materials & Continua, Vol.26, No.3, pp. 167-186, 2011, DOI:10.3970/cmc.2011.026.167

Abstract An improvement in the catalytic process of oxygen reduction reactions is of prime importance for further progress in low temperature fuel cell performance. This paper intends to investigate this problem from a fundamental quantum mechanics viewpoint. For this purpose, a hybrid density functional theory is employed to analyze the catalytic mechanism of the oxygen reduction at the fuel cell cathode. Major steps in the oxygen reduction that include the oxygen adsorption on solid metal clusters (e.g. Cu and Pt) and complete four proton transfer steps are simulated. Proton transfer processes from hydroniums to the adsorbed More >

Zone-Ching Lin¹, Chen-Hsing Cheng²

CMES-Computer Modeling in Engineering & Sciences, Vol.68, No.1, pp. 25-54, 2010, DOI:10.3970/cmes.2010.068.025

Abstract This study considers loadings on the multi-layer web frame structure and uses a novel method of the modified analytical hierarchy process (AHP) combined with modified theory of inventive problem solving (TRIZ) clustering to perform the creative structure design. The engineering knowledge of multi-layer web frame structure comprises such issues as vibration, yielding and buckling strength. Using the modified AHP, this study firstly applies the ratios of occurrence numbers of related keywords on different hierarchies to analyze the techniques and functions of multi-layer web frame structure, and finds out the priority order of feasible design decisions. More >

Jong Keun Moon¹, Seung Jo Kim²

CMES-Computer Modeling in Engineering & Sciences, Vol.67, No.3, pp. 239-264, 2010, DOI:10.3970/cmes.2010.067.239

Abstract Large structural problems with high precision and complexity require a high-performance computation using the efficient parallel algorithm. The purpose of this paper is to present the parallel performance of thermal-structural coupled analysis tested on a parallel cluster system. In the coupled analysis, the heat transfer analysis is carried out, and then the structural analysis is performed based on temperature distribution. For the automatic and efficient connection of two parallel analysis modules, the several communication patterns were studied. The parallel performance was demonstrated for the sample and the real application problems, such as a laminated composite More >

Che-Wun Hong^1,2, Chia-Yun Tsai¹

CMES-Computer Modeling in Engineering & Sciences, Vol.67, No.2, pp. 79-94, 2010, DOI:10.3970/cmes.2010.067.079

Abstract This paper describes the quantum mechanical simulation on the photonic properties of group-III nitride clusters, whose bulk types are common materials for light emitting diodes (LEDs). In order to emit different colors of light using the same semiconductor materials, it is possible to vary the band gap by controlling the quantum dot sizes or doping a third atom theoretically. Density functional theory (DFT) calculations are performed to analyze a set of binary (GaN)_n (3≤n≤32) and ternary In_xGa_1-xN (0≤x≤0.375) clusters to study their photonic characteristics. The ground state structures are optimized to calculate the binding energies using More >

MARCOS MORGAN

BIOCELL, Vol.32, No.1, pp. 9-26, 2008, DOI:10.32604/biocell.2008.32.009

Abstract The clustered protocadherins (Pcdhs) are single-pass transmembrane proteins that constitute a subfamily within the cadherin superfamily. In mammals, they are arranged in three consecutive clusters named α, β, and γ. These proteins are expressed in the nervous system and are targeted to mature synapses. Interestingly, different neurons express different subsets of isoforms; however, little is known about the functions and expression of the clustered Pcdhs.
Previous phylogenetic analyses that compared rodent and human clusters postulated the recent occurrence of gene duplication events. Using standard phylogenetic methods, I confirmed the prior observations, and I show that… More >