Computer software for modeling physical behavior, namely thermal, electrical, electro-thermal, thermo-mechanical behavior of electronic and opto-electronic devices, namely, data processing and storage devices, CD-ROMs, hard disk units, wireless communications devices and mobile phones, active components used in all kinds of cable and wireless networks, measurement and control systems, and parts for electronic and opto-electronic devices, namely, semiconductor devices such as discrete diodes, transistors and integrated circuits, micro-electro mechanical systems, multi-chip modules, printed circuit boards and system enclosures; discrete and integrated solid-state temperature sensors and measurement tools, namely, infrared imaging units, liquid crystals, thermometers and thermocouples, thermal transient testers, and thermal analyzers, thermostats used for steady-state or dynamic thermal characterization of electronic and optoelectronic data processing, storage and communications devices, measurement and control systems and parts thereof, namely, semiconductor devices, micro-electro mechanical systems, multi-chip modules, printed circuit boards and system enclosures