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This paper describes the development results of S tolerant Pt-Pd-based Diesel Oxidation Catalyst (DOC) which can be applied for passive DOC application, targeting Euro 4 and India BS4 emission standards with a view of the fact that in India the sulfur content is different in the 13 main cities compared to rest of the country. In order to develop a cost-effective DOC to meet Euro 4 and India BS4 legislation, Pt-Pd-based DOC was studied. Firstly, the effect of Pd used together with Pt in catalytic oxidation performance was studied. DOCs having different Pt to Pd ratios were evaluated in the engine exhaust. The results revealed that CO (Carbon Monoxides) and HC (Hydrocarbons) oxidation activity over Pt-Pd DOC were significantly improved as compared to Pt-only DOCs. It was also revealed that there is an optimum Pt to Pd ratio to give the best light-off performance under conditions tested. Advantage of Pd use with Pt was also confirmed in terms of thermal stability.

Finite element analysis is a well-established methodology in structural dynamics. However, optimization and/or probabilistic studies can be prohibitively expensive because they require repeated FE analyses of large models. Various reanalysis methods have been proposed in order to calculate efficiently the dynamic response of a structure after a baseline design has been modified, without recalculating the new response. The parametric reduced-order modeling (PROM) and the combined approximation (CA) methods are two re-analysis methods, which can handle large model parameter changes in a relatively efficient manner. Although both methods are promising by themselves, they can not handle large FE models with large numbers of DOF (e.g. 100,000) with a large number of design parameters (e.g. 50), which are common in practice. In this paper, the advantages and disadvantages of the PROM and CA methods are first discussed in detail.

In applications of the Energy Finite Element Analysis (EFEA) there is an increasing need for developing comprehensive models with a large number of elements which include both structural and interior fluid elements, while certain parts of the structure are considered to be exposed to an external fluid loading. In order to accommodate efficient computations when using simulation models with a large number of elements, joints, and domains, a substructuring computational capability has been developed. The new algorithm is based on dividing the EFEA model into substructures with internal and interface degrees of freedom. The system of equations for each substructure is assembled and solved separately and the information is condensed to the interface degrees of freedom. The condensed systems of equations from each substructure are assembled in a reduced global system of equations. Once the global system of equations has been solved the solution for each substructure is pursued.