Threshold-based Clustering with Hard Regularization for Intrusion Detection Systems

Alkyl alkanoate derivatives of substituted piperazines are stabilizers for synthetic polymeric materials normally subject to deterioration caused by ultraviolet light. The compounds may be formed by reacting a substituted piperazine with an acrylate or reacting a substituted piperazine with an alpha -haloalkanoate. Polymeric compositions containing these stabilizers may also contain a hindered phenolic compound. A typical embodiment is n-octadecyl- beta -(15{7,15-diazadispiro[5,1,5,3]hexadecane}propionate.