Thermography is becoming more widely used amongst construction professionals for energy related defect detection in buildings. Until quite recently, most of the research and practical use of building thermography has centred on employing a building walk-around or walkthrough methodology to detect sources of unacceptable energy use. However, thermographers are now creating new building thermography methodologies that seek to address some of the known limitations, such as camera spatial resolution, transient climatic conditions and differences in material properties. Often such limitations are misunderstood and sometimes ignored. This study presents a review of the existing literature, covering both well-established and emerging building thermography methodologies. By critically appraising techniques and observing methodology applications for specific energy related defects, a much clearer picture has been formed that will help thermographic researchers and thermographers to decide upon the best methodology for performing building thermography investigations and for the invention of new approaches. Whilst this paper shows that many of the different passive building thermography methodologies seek to address particular building issues such as defects and energy use, it has also demonstrated a lack of correlation between the different methodology types, where one methodology is often chosen over another for a particular reason, rather than making use of several methodologies to better understand building performance. Therefore this paper has identified the potential for using several passive building thermography methodologies together in a phased approach to building surveying using thermography. For example, a less costly and faster survey could be conducted to quickly identify certain defects before enabling more time consuming and expensive surveys to hone in on these with greater detail and spatial resolution if deemed necessary.

The value of mandatory securities disclosure is intensely debated. Two big questions occupy much of the attention: Do more accurate share prices contribute to the efficient provision of goods and services in the economy? Even if they do, will mandatory disclosure effectively contribute to share price accuracy? To date, the debate has been largely theoretical. This Article sheds much needed empirical light on the matter. After introducing a new technique from financial economics-R 2-to measure share price accuracy, the Article starts by discussing recent R 2 studies by ourselves and others addressing the first question. Using both cross country and cross industry comparisons, the results show that more accurate share prices improve capital allocation and thus do in fact contribute to the efficient provision of goods and services in the economy. The Article then presents a new R 2 study that we have conducted addressing the second question. The study examines the effect of a December 1980 change in the SEC's disclosure rule requiring every issuer's filings to contain a section with management's discussion and analysis of the issuer's financial results (the "MD&A" rule). The change required managers to disclose any material information suggesting that the issuer's most recent results are not necessarily indicative of future results. Our study shows that share prices became more accurate a result of the changed rule, suggesting that mandatory disclosure can in fact be effective.

a b s t r a c tBuilding thermography traditionally captures the thermal condition of building fabric at one single point in time, rather than changes in state over a sustained period. Buildings, materials and the environment are, however, rarely in a thermal equilibrium, which therefore risks the misinterpretation of building defects by employing this standard methodology. This paper tests the premise that time-lapse thermography can better capture building defects and dynamic thermal behaviour. Results investigating the temporal resolution required for time-lapse thermography over two case study houses found that under typical conditions small temperature differences (approximately 0.2 K) between thermal areas could be expected for 30-min image intervals. Results also demonstrate that thermal patterns vary significantly from day-to-day, with a 2.0 K surface temperature difference experienced from one day to the next. Temporal resolutions needed adjusting for different types of construction. Time-lapse experiments raised practical limitations for the methodology that included problems with the distance to target and foreground obstructions. At the same time, these experiments show that time-lapse thermography could greatly improve our understanding of building transient behaviour and possible building defects. Time-lapse thermography also enables enhanced differentiation between environmental conditions (such as clear sky reflections), actual behaviour and construction defects, thereby mitigating the risk of misinterpretation.

a b s t r a c tMany buildings suffer from defects in the building envelope, such as missing insulation, thermal bridging, cracks and moisture problems. Thermography is one technology that can help to identify such defects. However, there are different approaches towards assessing the building envelope. Pass-by thermography is an emerging method, which is used to capture single thermal images of external building elevations. Compared with traditional walk-through thermography, it is much quicker and cheaper to perform. Yet it is currently unclear how successful this methodology is at detecting building defects. This paper qualitatively compares pass-by thermography and walk-through thermography. A set of 122 residential dwellings in South West England was inspected using the both methodologies. Results show that substantially more defects were detected using walk-through thermography, with internal inspections yielding the greatest number of detected defects. Significant constraints with walk-past thermography were identified, such as unknown occupancy behaviour, transient climatic conditions, fixed viewing angles and spatial resolution limitations, which were all found to have a greater impact on image results than during walk-through thermography.Although trends in conductivity defects were found from target comparison analysis between similar dwellings, viewing single external elevations under walk-past thermography was found to miss many different defect types, which would have normally been discovered during traditional walk-through thermography.

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Bad corporate governance" is often invoked to explain poor enterprise performance, but the catch phrase is never precisely definedneither its consequences for the real economy, nor its causes in particular countries has been adequately explained. This paper uses Russian enterprise examples to address these open questions in corporate governance theory. We define corporate governance by looking to the economic functions of the firm rather than to any particular set of national corporate laws. Firms exhibit good corporate governance when their managers maximize residuals and, in the case of investor-owned firms, make pro rata distributions to shareholders. First, using this definition, we develop a typology that shows the channels through which bad corporate governance can inflict damage on the real economy. The topology helps identify vulnerabilities to corporate governance problems that may appear in any country and it suggests a new way to tailor policy responses. Second, we explain the causes of poor corporate performance in Russia by looking to the particular conditions prevailing at privatization-untenable initial firm boundaries and insider allocation of firm shares-and the bargaining dynamics that followed. The focus on initial conditions helps expand a comparative corporate governance literature built on United States, Western European, and Japanese models. Lessons from Russian fiascos counsel caution as to "stakeholder" proposals-including labor or local communities in formal corporate governance-and generate testable hypotheses regarding potential losses from the multiple large block share ownerships typical of many U.S. firms, especially close corporations.

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