1. User Interface System
- An user interface is something that connects between two entities. Every computer system that interacts with users has an user interface. This is the combination of hardware and software that enables the users to use the system. It is the user interface that makes the system most used. The user interface forms an important component of an information retrieval system since it connects the users to the organized information resources.
- Strive for consistency in terminology, layout, instructions, fonts and colour
- Provide shortcuts for skilled users.
- Provide appropriate and informative feedback about the sources and what is being searched for.
- Design for closure so that users know when they have completed searching the entire collection or have viewed every item in a browser list.
- Permit reversal of actions so that users can undo or modify actions;for example, they should be able to modify their queries or go back to the previous state in a search session.
- Support user control, allowing users to monitor the progress of a search and be able to specify the parameters to control a search.
- Reduce short-term memory load;the system should keep track of some important actions performed by the users and allow them to jump easily to a formerly performed action.
- Simple error-handling facilities to allow users to rectify errors easily;all error messages should be clear and specific.
- Provide plenty of space for entering text in search boxes.
- Provide alternative interfaces for expert and novice users.
2. Query Processing System
3. Database Modeling System
- Data modeling is a process by which the data requirements of an organisation or an application area are represented. Data exists as facts, figures and other bits of knowledge. When lot of data items are put together in a useful form one can get information. A data model is a schema to represent the real world using information concepts and structures. A model of data is a particular type of structure or manner of visualizing a data structure. A data structure is a collection of data elements or objects and relationships among them. A data model is a plan for building a database. It is a description of the data about entities, events, activities and their associations within an organization. The purpose of data model is to represent data which should be understandable. It is only then it can be used in some application. Modeling gives consideration only to the constituent elements and sequencing or placement of data elements within other elements. A data model in IRS is primarily a descriptive structure of data, not necessarily its meaning. Before 1980s, the two most commonly used database models were hierarchical and network systems. There are various data models now in use such as
- A flexible and easy to use Guided Search mode that does not require knowledge of the
- Dialog command language
- A robust Command Search mode that uses the powerful Dialog command language
- experienced searchers can easily use
- Database selection tools to help pinpoint the right database for your search
- Integrated database descriptions, pricing information, and other search assistance
- Easy to use forms to create and modify Alerts (current awareness updates)
- Search results available in HTML or text formats