What is BIM?

Building Information Modelling (BIM) is a new three-dimensional modelling technology and an integrated process that allows the building professionals of various disciplines to explore the building project digitally, before it is built.

3D versus 2D

Traditionally, in a two-dimensional drawing, each building professional prepares their own plans. Due to the limitations of a two-dimensional drawing, certain design clashes (e.g., pipes running into the air-con ventilation tubes) would appear only during construction. With BIM, a three-dimensional model of a project and drawings can be shared among these professionals. This allows the professionals – architects, engineers and contractors – to analyse and resolve potential design clashes before construction begins. BIM will facilitate better teamwork among the professionals, helping to reduce unnecessary reworks when the project is being constructed.

Building professionals: How BIM benefits them?

Architects can:
• create three-dimensional models (that help other professionals to visualise his drawings)
• perform sustainability analysis,
• co-ordinate the work on the project with other professionals from various disciplines, and
• produce construction documents and drawings quickly.

Structural engineers can:
• perform structural analysis of the buildings in the project, and
• design and produce construction documents and drawings of the building structures quickly.

Structural professionals can:
• erect the structural steel connections of a building easily,
• determine the multi-material configuration for rebar and steel members,
• fabricate precast panel elements with greater accuracy.

M&E engineers can:
• determine the locations of all electrical installations within the building project, and
• plan the distribution and routes of mechanical equipment during construction.

Contractors can:
• get an overview of the entire construction process through the computer simulation and
• determine, review and optimise the sequence of the building’s construction.

RFID Security Technology

An RFID system consists of a tag (transponder) and a reader (interrogator). The technology of RFID deals with the remote collection of information stored on a tag using radio frequency communications. Information stored on the tag can range from as little as an identification number, to kilo-bytes of data written to and read from the tag, to dynamic information maintained on the tag, such as temperature histories. The information from the tag/reader combination is either presented to a human operator typically using a hand-held device with a alpha-numeric display or a host computer which automatically manages the information.

Critical performance variables in an RFID system involve the range at which communication can be maintained, the size of the information space contained on the tag, the rate at which the communication with the tag can take place, the physical size of the tag, the ability of the system to "simultaneously" communication with multiple tags, and the robustness of the communication with respect to interference due to material in the path between the reader and the tag. Several factors determine the level of performance that can be achieved in these variables. The factors include the legal/regulatory emission levels allowed in the country of use, whether or not a battery is included in the tag to assist its communication back to the reader, and the frequency of the RF carrier used to transport the information between the tag and the reader.

Frequency

Over the course of decades of RFID development, industry has evolved RFID solutions that variously trade the regulatory constraints, the signal propagation characteristics of various RF carrier frequencies, and the economics of tag size and optional batteries. These solutions employ only a few RF frequencies around which the vast majority of RFID systems are fielded today. The RF frequencies include relatively narrow bands centered at: 125/134KHz or low frequency (LF) 13.56MHz or high frequency (HF) 433/869/915MHz or ultra-high frequency (UHF) 2.45/5.8GHz or micro-wave (uW) These frequency values are commonly referred to the RFID technology. Thus, tags and readers combinations are described as employing LF, HF, UHF, or uW technology