The design of information architecture is an essential step in an uncertain environment, where the rates of external and internal change and the rate of technological change are high. Currently, the world of systems development has been dominated by structured methodologies for large-scale projects and by object-oriented or visual-oriented approaches. In this paper we compare and contrast structured and object-oriented modeling techniques in terms of their parameters such as understandability of the representation, and the dynamics of their processes.

Object-oriented modeling techniques are based on the concept that data and behavior should be encapsulated together and that the issues surrounding both must be taken into consideration in order to model software that is extensible, scalable and flexible. On the other hand the main concept underlying structured modeling is that every model can be viewed as a set of smaller models or distinct elements that are organized into hierarchical structure. Hence, Structured Modeling (SM) inspired the development of certain languages by giving perspective for building models from smaller objects, as in the case of object-oriented modeling features.

The Structured Modeling Language (SML) is one of the simplest and common languages that support the structured modeling semantic framework. SML has the capability unlike in other modeling systems to support error-checking; the use of hierarchical organization as an approach to managing model complexity, and also as a visual device for model navigation; has complete independence between the general structure of a class of models and instantiating data, a feature that promotes the reuse of each of these, conciseness, efficient communication, and dimensional flexibility. The structured modeling projects allow the development of models formed by entity-relationship diagrams, data flow diagrams and state chart diagrams. A directed acyclic graph is often used to represent the dependencies that exist among them.

Likewise, Unified Modeling Language (UML) is the official language for object-oriented modeling in all areas. Therefore, UML is the industry-standard language for specifying, visualizing, constructing, and documenting the artifacts of software systems. It simplifies the complex process of software design, creating a "blueprint" for construction.  In application, object-oriented projects allow the development of UML diagrams such as: use case diagrams, class diagrams, collaboration diagrams, sequence diagrams, and state char diagrams. Its understandability together with separation of concerns and modularization, leads to homogeneity of and consistency between model parts, views and aspects.

Object-oriented modeling is more flexible than structured-modeling as it allows for interchanging of component modules among whole-system models as well as making it easier to maintain and change the component modules. This modular design also promotes concept sharing and reusability. Further, it supports visual presentation that includes semantic content, data integrity, and also supports both structural and data independence. As a result, it represents the real world as closely as possible. However in real life application, it has steep learning curve, its complex and posses high system overhead that slows transactions.

Likewise SM supports conceptual simplicity, data independence, data integrity and is proposed as a cure for information disarray i.e. fragmentation, redundancy, inconsistency and inscrutability in the context of high technology manufacturing. Its disadvantages include: complex implementation, difficult to manage, lacks structural independence, and implementation limitations.

Structured modeling and Object-oriented modeling are both similar in a sense that they both support static data models. That is, concepts such as Objects, Classes, Inheritance, and Classes Hierarchy, etc in structured modeling play almost the same roles, hence, are clearly in the scope of static data models and can be managed the way objects are managed in object-oriented modeling technique. Another similarity lies in their functional model, which represents the transformational aspects of the system and data-flow mechanism. That is, it describes the data and control flow within the system.

However, the object-oriented modeling has dynamic model feature, which is not present or limited in structured modeling. Dynamic models help to break down a problem into its sub-problems. It can be used during design, when details as dataflow and conditional constraints have to be modeled. For the implementation phase it can serve in two ways. It gives a specification of the software component and it can be generated from the existing code, to represent the actual state of the project. Therefore, the dynamic model shows behavior and function. But since, the functional model is often considered part of dynamic model, the structured modeling has some limited capabilities of dynamic model.

 Research shows that object-oriented modeling promotes better understanding of requirements, clear designs, and more easily maintainable systems than structure modeling technique. Since structure modeling is used in simulations, this concept can be used to add object-oriented modeling features to give it the dynamic system capability.

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