Zhejiang Gongshang University

About: Zhejiang Gongshang University is a education organization based out in Hangzhou, China. It is known for research contribution in the topics: Adsorption & Supply chain. The organization has 8258 authors who have published 7670 publications receiving 90296 citations. The organization is also known as: Zhèjiāng Gōngshāng Dàxué.

Web user clustering analysis based on KMeans algorithm

Abstract: As one of the most important tasks of Web Usage Mining (WUM), web user clustering, which establishes groups of users exhibiting similar browsing patterns, provides useful knowledge to personalized web services. In this paper, we cluster web users with KMeans algorithm based on web user log data. Given a set of web users and their associated historical web usage data, we study their behavior characteristic and cluster them. Experiment results show the feasibility and efficiency of such algorithm application. Web user clusters generated in this way can provide novel and useful knowledge for various personalized web applications.

Mechanisms and origins of switchable regioselectivity of palladium- and nickel-catalyzed allene hydrosilylation with N-heterocyclic carbene ligands: a theoretical study.

Abstract: The mechanisms and origins for the Pd- and Ni-catalyzed regioselective hydrosilylation of allene have been investigated by means of density functional theory (DFT) calculations. The free-energy profiles of Pd- and Ni-catalyzed reactions with small and bulky N-heterocyclic carbene (NHC) ligands are calculated to determine the mechanism for regioselectivities. The calculation results show that different metals (Ni vs Pd) lead to regiochemical reversals for the hydrosilylation of allene. The allylsilane is the major product via palladium catalysis with small NHC ligand, while the vinylsilane is the major product via nickel catalysis with bulky NHC ligand. Both electronic and steric factors play a key role in the regioselectivities for the hydrosilylation of allene via Pd and Ni catalysts. The calculation results are in good agreement with observed regioselectivities and could provide insights into the design of new catalysts for the regioselectivity of hydrosilylation reactions.