Technical Due Diligence: Study of Building Evaluation Practice

Technical due diligence (TDD) as an evaluation of the performance of constructed facilities has become an important new field of practice for consultants. Before the financial crisis started in autumn 2008, TDD represented the fastest growing activity in some consulting companies. TDD is usually carried out for buyers or sellers involved in real estate transactions. It can also be part of mergers, including real estate and other assets, or part of facilities management outsourcing. This paper is based on a case study and an interview survey of companies involved in TDD consulting in Denmark and Italy during 2009. The research identifies the current practice and compares it with the recommended practice in international guidelines. The current practice is very diverse and could, in many cases, be improved by a more structured approach and stricter adherence to international guidelines. However, the investigation of the current practice also identifies examples of value-adding practices, which can give the companies in question competitive advantages by differentiation and/or give input to improvements of the recommended practice guidelines.     

Simple tool to evaluate the impact of daylight on building energy consumption

This paper presents a simple building simulation tool for integrated daylight and thermal analysis. The tool is capable of importing the thermal and visual properties for different glazings and shading positions from the Window Information System (WIS) program. A coupled ray-tracing and radiosity methodology is used to derive the daylight levels for different sky conditions. Both detailed daylight distribution for a particular day and time and hourly discrete values on a yearly basis may be obtained. For an integrated simulation the hourly daylight levels are fed into an existing simple thermal simulation program capable of calculating energy demand and the indoor environment. Straightforward control systems for general and task lighting systems have been implemented together with a shading control strategy that adjusts the shading according to the indoor operative temperature, the risk of glare and the profile angle of the sun. The implemented daylight calculation method allows for shades from the window recess and overhang, and for distant shades blocking the sky vault. Comparisons with the ray-tracing program Radiance show that the accuracy of this approach is adequate for predicting the energy implications of photoresponsive lighting control. The amount of input is small, which makes the tool useful for integrated daylight optimisation in the early design process.     

Estimating forest parameters using Landsat ETM+ spectral responses and monocultured plantation fieldwork measurements data

Forest parameters, such as mean diameter at breast height (DBH), mean stand height (H) or volume per hectare (V), are imperative for forest resources assessment. Traditional forest inventory that is usually based on fieldwork is often difficult, time-consuming, and expensive to conduct over large areas. Therefore, estimating forest parameters in large areas using a traditional inventory approach combined with satellite data analysis can improve the spatial estimates of forest inventory data, and hence be useful for sustainable forest management and natural resources assessment. However, extracting practical information from satellite imagery for such purpose is a challenging task mainly because of insufficient knowledge linking forest inventory data to satellite spectral response. Here, we present the use of a cost-free Landsat-7 Enhanced Thematic Mapper Plus (ETM+) in order to explore whether it is possible to combine all available optical bands from a specific sensor for improving forest parameter spatial estimates, based on fieldwork at Lahav and Kramim Forests, in the Israeli Northern Negev. A generic strategy, based on morphological structuring element, convex hall and spectral band linear combination algorithms, was developed in order to extract the mathematical dependencies between the forest inventory measurements and linear combination sets of Landsat-7 ETM+ spectral bands, which yields the highest possible correlation with the forest inventory measured data. Using the mathematical dependency functions, we then convert the entire Landsat-7 ETM+ scenes into forest inventory parameter values with sufficient accuracy and tolerance errors needed for sustainable forest management. The root mean square error obtained between the measured and the estimated values for Lahav Forest are 0.70 cm, 0.29 m, and 1.48 m³ ha^?1 for the mean DBH, H, and V, respectively, and for Kramim forest are 0.61 cm, 0.70 m, and 6.31 m³ ha^?1, respectively. Furthermore, the suggested strategy could also be applied with other satellites data sources.     

Top-spray fluid bed coating: Scale-up in terms of relative droplet size and drying force

Top-spray fluid bed coating scale-up experiments have been performed in three scales in order to test the validity of two parameters as possible scaling parameters: The drying force and the relative droplet size. The aim was to be able to reproduce the degree of agglomeration as well as the mechanical properties of the coated granules across scale. Two types of placebo enzyme granule cores were tested being non-porous glass ballotini cores (180–350 μm) and low porosity sodium sulphate cores (180–350 μm). Both types of core materials were coated with aqueous solutions of Na₂SO₄ using Dextrin as binder. Coating experiments were repeated for various drying force and relative droplet size values in three top-spray fluid bed scales being a small-scale (Type: GEA Aeromatic-Fielder Strea-1), medium-scale (Type: Niro MP-1) and large-scale (Type: GEA MP-2/3). The tendency of agglomeration was assessed in terms of particle size fractions larger than 425 μm determined by sieve analysis. Results indicated that the particle size distribution may be reproduced across scale with statistical valid precision by keeping the drying force and the relative droplet size constant across scale. It is also shown that none of the two parameters alone may be used for successful scaling. Morphology and microscope studies indicated that the coating layer is homogenous and has similar structures across scale only when both the drying force and the relative droplet size were fixed. Impact and attrition tests indicated that it is possible to produce granules with similar attrition and impact strength across scale and that the two types of mechanical properties are inversely related.     

Use of Models to Support the Monitoring Requirements in the Water Framework Directive

Implementation of the EU Water Framework Directive (WFD) poses many new challenges to European water managers. Monitoring programmes play a key role to assess the status and identify possible trends in the environmental conditions of river basins; to gain new knowledge on water processes and to assess to which extent implemented measures actually have the expected effects in terms of improving the environmental status. Despite a general acknowledgement in the scientific community on the benefits of using monitoring and modelling jointly, it has not been the common practise in the European monitoring programmes so far. Several obstacles may be identified which limits the joint use of monitoring and modelling, such as lack of the required skill, lack of time, lack of confidence in models but also a lack of awareness on how models can be used in practise. In this paper we provide examples on how modelling can support the monitoring programmes to meet the objectives of the monitoring programmes in the WFD more efficiently. The extent to which the monitoring requirements in the WFD can be expected to supply sufficient data for modelling purposes is further addressed. This question is, however, not well posed, as the data requirement for modelling is highly dependent on the required accuracy of the model results.     

Organocatalysis in Natural Product Synthesis: A Simple One‐Pot Approach to Optically Active β‐Diols

Optically active β‐diols have been prepared using an organocatalytic one‐pot approach from α,β‐unsaturated aldehydes using (E)‐benzaldehyde oxime as nucleophile in an oxa‐Michael reaction with subsequent in situ reduction or Grignard addition. With this protocol at hand, two biologically active compounds, an insect sex pheromone and a glycerol kinase substrate have been synthesized.     

Surface-Enhanced Raman Scattering Detection of pH with Silica-Encapsulated 4-Mercaptobenzoic Acid-Functionalized Silver Nanoparticles

Sensors based upon surface-enhanced Raman spectroscopy (SERS) are attractive because they have narrow, vibrationally specific spectral peaks that can be excited using red and near-infrared light which avoids photobleaching, penetrates tissue, and reduces autofluorescence. Several groups have fabricated pH nanosensors by functionalizing silver or gold nanoparticle surfaces with an acidic molecule and measuring the ratio of protonated to deprotonated Raman bands. However, a limitation of these sensors is that macromolecules in biological systems can adsorb onto the nanoparticle surface and interfere with measurements. To overcome this interference, we encapsulated pH SERS sensors in a 30 nm thick silica layer with small pores which prevented bovine serum albumin (BSA) molecules from interacting with the pH-indicating 4-mercaptobenzoic acid (4-MBA) on the silver surfaces but preserved the pH-sensitivity. Encapsulation also improved colloidal stability and sensor reliability. The noise level corresponded to less than 0.1 pH units from pH 3 to 6. The silica-encapsulated functionalized silver nanoparticles (Ag-MBA@SiO(2)) were taken up by J774A.1 macrophage cells and measured a decrease in local pH during endocytosis. This strategy could be extended for detecting other small molecules in situ.     

APPLICATION OF AERIAL DIGITAL PHOTOGRAPHY FOR MACROPHYTE COVER AND COMPOSITION SURVEY IN SMALL RURAL STREAMS

Macrophytes are a key biological component in many fluvial ecosystems. In altered streams, they can become highly dominant features, covering extensive parts of the channel with cascading effects on stream conditions and biological composition. The aim of this study is to examine the possibility of using information collected by aerial digital photography‐spectral analysis (ADP‐SA) as an alternative, cost‐effective methodology to the commonly used spectral procedure at a large (section) scale, and to the ground level visual survey (gridded frame) at a smaller (organism) scale. Cladophora glomerata and Nasturtium officinale, were selected as the targeted macrophyte species and classified at the same time (species relative cover) by using the three methodologies. Our findings show that the ADP‐SA methodology was able to detect species and relative cover in similar accuracy (≤10% differences) at the two spatial scales. ADP‐SA had a better spatial resolution than both the hyperspectral and the visual methodology (4 cm vs. 1 m and 10 cm, respectively) and was capable to differentiate submerged from emergent plants. However, on a smaller scale, ground level work is suitable and essential for detecting rarer species and is not hindered by weather, canopy cover or multi‐layered plant composition. ADP‐SA can therefore add a cost‐effective and nonsubjective practice to the existing tool kit of macrophyte surveys, particularly in small streams, which require high spatial resolution. Copyright © 2013 John Wiley & Sons, Ltd.