Security Design Patterns present the tried and tested design decisions made by security engineers within a well documented format. Patterns allow for complex security concepts, and mechanisms, to be expressed such that non-domain experts can make use of them. Our research is concerned with the development of pattern languages for advanced crypto-systems. From our experience developing pattern l...

Anti-patterns are motifs that are usually thought to be good solutions to some design or implementation problems, but back-fires badly when applied. Previous studies have reported that anti-patterns make object oriented systems hard to maintain. Anti-patterns motifs usually have dependencies with other classes in the system. In this paper, we propose to analyse these dependencies (with in parti...

Since the mid-1990’s the psychological and sociological concept of trust has received increasing attention in the field of electronic commerce by many scholars and was recognized as one of the main reasons why a high number of consumers are still reluctant from buying on the Internet. During about the same period of time the idea of design patterns and pattern languages, originally developed in...

Rectangulations are partitions of a square into axis-aligned rectangles. A number of results provide bijections between combinatorial equivalence classes of rectangulations and families of pattern-avoiding permutations. Other results deal with local changes involving a single edge of a rectangulation, referred to as flips, edge rotations, or edge pivoting. Such operations induce a graph on equi...

We review how the monotone pattern compares to other patterns in terms of enumerative results on pattern avoiding permutations. We consider three natural definitions of pattern avoidance, give an overview of classic and recent formulas, and provide some new results related to limiting distributions.

Software Design Patterns are reusable designs providing common solutions to the similar kind of problems in software development. Creational patterns are that category of design patterns which aid in how objects are created, composed and represented. They abstract the creation of objects from clients thus making the application more adaptable to future requirements changes. In this work, it has...

In this paper we consider the enumeration of binary trees avoiding non-contiguous binary tree patterns. We begin by computing closed formulas for the number of trees avoiding a single binary tree pattern with 4 or fewer leaves and compare these results to analogous work for contiguous tree patterns. Next, we give an explicit generating function that counts binary trees avoiding a single non-con...

FactoryDef : DPDef name = "Abstract Factory" L1 : LevelDef AF : RoleDef name = "Abstract Factory" L2 : LevelDef L3 : LevelDef CF : RoleDef name = "Concrete Factory" AP : RoleDef name = "Abstract Product" L4 : LevelDef CP : RoleDef name = "Concrete Product" root

I propose a modern OO language update of the Parameterized Factory Creational Pattern [Gamma95]. It is compact since it folds the Factory method into an abstract base class, and imposes a package structure on its concrete subclasses. The design is demonstrated in Java, but is also applicable to C# and other modern object-oriented languages.