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The discrete-time Distributed Bayesian Filtering (DBF) algorithm is presented for the problem of tracking a target dynamic model using a time-varying network of heterogeneous sensing agents. In the DBF algorithm, the sensing agents combine their normalized likelihood functions in a distributed manner using the logarithmic opinion pool and the dynamic average consensus algorithm. We show that each agent's estimated likelihood function globally exponentially converges to an error ball centered on the joint likelihood function of the centralized multi-sensor Bayesian filtering algorithm. We rigorously characterize the convergence, stability, and robustness properties of the DBF algorithm. Moreover, we provide an explicit bound on the time step size of the DBF algorithm that depends on the time-scale of the target dynamics, the desired convergence error bound, and the modeling and communication error bounds. Furthermore, the DBF algorithm for linear-Gaussian models is cast into a modified form of the Kalman information filter. The performance and robust properties of the DBF algorithm are validated using numerical simulations.

An ab initio study was carried out on coherent and semicoherent interfacial energies for fcc Fe/MCs (NaCl structure, M = Ti, Zr, Hf, V, Nb, Ta) systems. The group V transition metal carbides have lower coherent and semicoherent interfacial energies than group IV transition metal carbides. Also, the coherent interfacial energies for fcc Fe/MCs systems are lower than those for bcc Fe/MCs systems. The difference between semicoherent and coherent interfacial energy for fcc Fe/MC systems becomes larger as the misfit increases. The semicoherent interfacial energies at relaxed interfaces Fe/TiC, Fe/ZrC, Fe/HfC, Fe/VC, Fe/NbC and Fe/TaC were 0.600 J m−2, 0.661 J m−2, 0.946 J m−2, −0.050 J m−2, 0.320 J m−2 and 0.380 J m−2, respectively. In order to maximize precipitation strengthening effect in austenitic steel, VC is the most favorable precipitate under consideration.

An ab initio study was carried out on interface energies, misfit strain energies, and electron structures at coherent interfaces between bcc Fe and MCs (NaCl structure, MϭV, Nb, Ta). The interface energies at relaxed interfaces Fe/VC, Fe/NbC, and Fe/TaC were Ϫ0.120, Ϫ0.169 and Ϫ0.158 J/m 2 , respectively. Influence of bond energy was estimated using the discrete lattice plane/nearest neighbor broken bond (DLP/NNBB) model. It was found that the dependence of interface energy on the type of carbide was closely related to changes of the bond energies between Fe, M and C atoms before and after formation of the interfaces Fe/MC. The misfit strain energies in Fe/VC, Fe/NbC, and Fe/TaC systems were 0.086, 0.891 and 0.827 eV per 16 atoms (Fe; 8 atoms and MC; 8 atoms), respectively. The misfit strain energy became larger when difference of lattice parameters between the bulk Fe and the bulk MCs increased.KEY WORDS: interface energy; misfit strain energy; transition metal carbides; bcc iron; ab initio calculation.

A numerical simulation based on the finite element method was used to obtain the optimal electrodeposition condition at a patterned cathode. The calculated deposition rates agreed well with the measured ones. Influences of the following parameters on uniformity of electrodeposit have been studied; width of auxiliary electrode, gap between cathode and auxiliary electrode, distance between the inner wall of bath and auxiliary electrode, shape of auxiliary electrode, paddle velocity, gap between cathodes and paddles, anode size.