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Tolerance analysis is a very important tool for chip design in the microelectronics industry. The usual method for tolerance analysis is Monte Carlo simulation, which, however, is extremely CPU intensive, because in order to yield statistically significant results, it needs to generate a large sample of function values. Here we report on another method, recently introduced in several fields, called stochastic response surface method, which might be a viable alternative to Monte Carlo simulation for some classes of problems. The application considered here is on the tolerance analysis of the current of a submicrometer n⁺‐n‐n⁺ diode as a function of the channel length and the channel doping. The numerical simulator for calculating the current is based on the energy transport hydrodynamical model introduced by Stratton, which is one of the most widely used in this field.

Heritage or historic building information modelling (BIM), often referred to as HBIM, is becoming an established feature in both research and practice. The advancement of data capture technologies such as laser scanning and improved photogrammetry, along with the continued power of BIM authoring tools, has provided the ability to generate more accurate digital representations of heritage buildings which can then be used during renovation and refurbishment projects. Very often these representations of HBIM are developed to support the design process. What appears to be often overlooked is the issue of conservation and how this can be linked to the BIM process to support the conservation management plan for the building once it is given a new lease of life following the refurbishment process. The paper aims to discuss these issues.

The paper presents a review of the context of conservation and HBIM, and then subsequently presents two case studies of how HBIM was applied to high-profile renovation and conservation projects in the UK. In presenting the case studies, a range of issues is identified which support findings from the literature noting that HBIM is predominantly a tool for the geometric modelling of historic fabric with less regard for the actual process of renovation and conservation in historic buildings.

Lessons learnt from the case studies and from existing literature are distilled to develop a framework for the implementation of HBIM on heritage renovation projects to support the ongoing conservation of the building as an integral part of a BIM-based asset management strategy. Five key areas are identified in the framework including value, significance, recording, data management and asset management. Building on this framework, a conceptual overlay is proposed to the current Level 2 BIM process to support conservation heritage projects.

This paper addresses the issue of HBIM application to conservation heritage projects. Whilst previous work in the field has identified conservation as a key area, there is very little work focusing on the process of conservation in the HBIM context. This work provides a framework and overlay which could be used by practitioners and researchers to ensure that HBIM is fully exploited and a more standardised method is employed which could be used on conservation heritage renovation projects.