Optical full Hadamard matrix multiplexing and noise effects: errata

The model for Poisson random noise under Hadamard multiplexing is revised. The new model accounts for the variation of the Hadamard multiplexed measurements, as well as the previously considered variation due to Poisson fluctuations. A numerical simulation matches the model prediction within uncertainty

Colour image processing and texture analysis on images of porterhouse steak meat

This paper outlines two colour image processing and texture analysis techniques applied to meat images and assessment of error due to the use of JPEG compression at image capture. JPEG error analysis was performed by capturing TIFF and JPEG images, then calculating the RMS difference and applying a calibration between block boundary features and subjective visual JPEG scores. Both scores indicated high JPEG quality. Correction of JPEG blocking error was trialled and found to produce minimal improvement in the RMS difference. The texture analysis methods used were singular value decomposition over pixel blocks and complex cell analysis. The block singular values were classified as meat or non- meat by Fisher linear discriminant analysis with the colour image processing result used as ‘truth.’ Using receiver operator characteristic (ROC) analysis, an area under the ROC curve of 0.996 was obtained, demonstrating good correspondence between the colour image processing and the singular values. The complex cell analysis indicated a ‘texture angle’ expected from human inspection

Optical full Hadamard matrix multiplexing and noise effects

Hadamard multiplexing provides a considerable SNR boost over additive random noise but Poisson noise such as photon noise reduces the boost. We develop the theory for full H-matrix Hadamard transform imaging under additive and Poisson noise effects. We show that H-matrix encoding results in no effect on average on the noise level due to Poisson noise sources while preferentially reducing additive noise. We use this result to explain the wavelength-dependent varying SNR boost in a Hadamard hyperspectral imager and argue that such a preferential boost is useful when the main noise source is indeterminant or varying

Forest vegetation management in Europe: current practice and future requirements

The book provides a record of the co-operation within Europe in the field of forest vegetation management through the Cost Action E47. The aims are: i)to provide a summary of the current state of the art' as it applies to forest vegetation management in Europe for scientists, practitioners and policymakers, affiliated to state, non-governmental or private commercial organizations; ii)to document existing forest weed control practices across Europe, and hence provide a resource of alternative solutions for individual countries sharing similar conditions and challenges; and iii)to identify common information gaps and future research needs, and hence potential future areas of collaboration for forest vegetation management scientists across Europe, along with barriers that may need to be overcome to achieve that aim.FORET;PEUPLEMENT FORESTIER;VEGETATION;CONCURRENCE VEGETALE;LUTTE;MODE DE TRAITEMENT;COOPERATION INTERNATIONALE;RECHERCHE DEVELOPPEMENT;DEVELOPPEMENT DURABLE;AMENAGEMENT FORESTIER;MAUVAISE HERBE;CONTROLE DE LA VEGETATION;PESTICIDE;LUTTE PHYTOSANITAIRE;IMPACT SUR L'ENVIRONNEMENT;DYNAMIQUE DE VEGETATION;HERBICIDE;BIODIVERSITE;ECOSYSTEME;HISTOIRE;GESTION FORESTIERE;EUROPE;VEGETATION FORESTIERE;ADVENTICE;ALTERNATIVES AUX HERBICIDES;

Lessons Learned from Continuous Commissioning® of a LEED Gold Building in Texas

The subject building is a relatively new building with 120,000 square feet located in Texas and was the first LEED® Gold building in the area. To earn the title of a green building, the designers of this high performance building included many conservation and energy related design features and construction practices. The energy related design features of the building include a roof mounted photovoltaic system, a green roof design, and connection to a district cooling system which utilizes thermal storage. Many of the operations and mechanical issues identified during the course of commissioning the subject building are items common to many commercial buildings, green or conventional. The potential cost savings from implementing the measures is 21% of the annual energy consumption with a simple payback of less than one year. The findings at the subject building suggest that: • High performance buildings have many of the same problems as conventional buildings since none of the issues and opportunities identified would generally be considered unique to high performance buildings • The potential for savings from commissioning the systems in high performance buildings is similar to that of conventional buildings and is as economically attractive

Impact of Nighttime Shut Down on the Prediction Accuracy of Monthly Regression Models for Energy Consumption in Commercial Buildings

Regression models of measured energy use in buildings are widely used as baseline models to determine retrofit savings from measured energy consumption. It is less expensive to determine savings from monthly utility bills when they are available than to install hourly metering equipment. However, little is known about the impact of nighttime shut off on the accuracy of savings determined from monthly data. This paper reports a preliminary investigation of this question by comparing the heating and cooling energy use predicted by regression models based on monthly data against the predictions of calibrated hourly simulation models when applied to a medium-sized university building in Texas with (i) DDCAV system operating 24 hours per day, (ii) DDCAV system with nighttime shut down, (iii) DDVAV system operating 24 hours per day, and (iv) DDVAV system with nighttime shut down. The results of the four cases studied indicate : 1) when the AHUs are operated 24 hours/day, the annual prediction error of the cooling regression models is less than 0.5% of the annual cooling energy consumption; however, 2) when the AHUs are operated with nighttime shut down, the annual prediction error of the cooling models becomes as high as 6% of annual energy consumption. It should be noted that the cases considered here include only single end-uses of energy and have not investigated energy-use data which includes multiple end-uses. Modified regression models are therefore recommended when AHUs are not operated 24 hours per day and the temperature pattern is significantly different between pre and post retrofit years

Lessons Learned from Continuous Commissioning of the Robert E. Johnson State Office Building, Austin, TX

The Robert E. Johnson State Office building is a 5-story, 303,389 square foot office building built in 2000 located in downtown Austin, TX. The original building design included a number of energy conservation measures that were incorporated into the final construction. During the investigation of the building, four energy conservation measures were identified, three of which deal with conventional HVAC systems. The fourth is related to the currently unutilized daylighting system which was one of the energy conservation measures of the original building design. Utilizing this system would lead to approximately 18.5% annual lighting energy savings or 5.6% annual whole building energy savings based on a DOE-2 simulation analysis. Three main lessons were learned from the experience with the Robert E. Johnson building: • The traditional design-construction-operation team must include the energy conservation analysis team • The entire building process should be reorganized to assure that complete information is provided and passed on from the energy conservation analysis team • High performance buildings should be continuously monitored and analyze

Bridging the Gap Between Commissioning Measures and Large Scale Retrofits in Existing Buildings

Most often commissioning of existing buildings seeks to reduce a building’s energy consumption by implementation of operational changes via the existing equipment. In contrast, large scale capital retrofits seek to make major changes to the systems installed in the building to reach the same goal. The purpose of the investigations presented here is to find energy-saving measures which economically fall between the retro-commissioning measures which typically have very short paybacks and the large scale capital retrofits which typically have significantly longer paybacks. Based on a simulation analysis of three previously retro-commissioned university buildings, it was determined that all three are currently consuming more energy than would be expected under ideal operating conditions. The simulation estimated annual savings potential for the three buildings range from 28-44% of whole building energy consumption. A research level assessment of each has been conducted to identify the reasons why the subject buildings are not operating as efficiently as possible and energy saving measures are presented to bring the buildings as close to ideal operation as possible. This work seeks to determine if an on-site assessment can identify commissioning measures that realize a substantial portion of the indicated savings potential or whether it appears that there are reasons that would preclude commissioning measures from achieving significant savings. If it is not practical to implement commissioning measures due to antiquated controls, missing sensors, or other reasons, these investigations identify rapid payback retrofit measures that achieve as much of the projected savings as possible. The analysis indicates that 30-100% of the estimated savings potential can be realized in the three subject buildings with estimated paybacks of less than 3 years

Pre-Retrofit Lighting Study at the University of Texas at Arlington

In the summer of 1993 the University of Texas at Arlington Physical Plant Department submitted a request to the Energy Systems Lab to conduct a lighting study to determine the most cost-effective method of implementing energy-saving lighting retrofits in U.T. Arlington classrooms without compromising the Illuminating Engineering Society (IES) recommended minimum lighting levels. A preliminary series of field tests was undertaken to get a sampling of classroom lighting levels on the U.T. Arlington campus and to determine whether lamp locations within the fixture would impact the amount of light output. This was followed by a series of lab tests conducted at the Energy Systems Lab, located on the Texas A&M University campus, to compare the light output of fixtures with different combinations of lamp types and locations within the fixture. In order to evaluate the impact of the proposed lighting retrofit, a study was made to determine the capital investment required as weighed against energy cost savings. The results of the study are presented in the paper and a summary table is provided to take into account lamp and ballast performance compared with capital expenditure with respect to meeting IES minimum footcandle levels. Based on the report findings it was recommended that a full, comprehensive survey be undertaken at UTA, to ensure that minimum lighting levels will be maintained, while also ensuring that the capital investment is the most cost-effective