Comparative study of vision tracking methods for tracking of construction site resources

Vision tracking has significant potential for tracking resources on large scale, congested construction sites, where a small number of cameras strategically placed around the site could replace hundreds of tracking tags. The correlation of vision tracking 2D positions from multiple views can provide the 3D position. However, there are many 2D vision trackers available in the literature, and little information is available on which one is most effective for construction applications. In this paper, a comparative study of various vision tracker categories is carried out, to identify which one is most effective in tracking construction resources. Testing parameters for evaluating categories of trackers are identified, and benefits and limitations of each category are presented. The most promising trackers are tested using a database of construction operations videos. The results indicate the effectiveness of each tracker in relation to each parameter of the test, and the most suitable tracker needed to research effective 3D vision trackers of construction resources.     

Structural Test and Diagnosis for Graceful Degradation of NoC Switches

Networks-on-Chip (NoCs) are implicitly fault tolerant and due to their inherent redundancy they can overcome defective cores, links and switches. This effect can be used to increase yield at the cost of reduced performance. In this paper, a new diagnosis method based on the standard flow of industrial volume testing is presented, which is able to identify the intact functions of a defective network switch rather than providing only a pass/fail result for the complete switch. To achieve this, the new method combines for the first time the precision of structural testing with information on the functional behavior in the presence of defects. This allows to disable defective parts of a switch after production test and use the intact functions. Thereby, only a minimum performance decrease is induced while the yield is increased. According to the experimental results, the method improves the performability of NoCs since 56.86?% and 72.42?% of defects in two typical switch models only impair one switch port. Unlike previous methods for implementing fault tolerant switches, the developed technique does not impose any additional area overhead and is compatible with many common switch designs.     

Development of building energy asset rating using stock modelling in the USA

The US Building Energy Asset Score helps building stakeholders quickly gain insight into the efficiency of building systems (envelope, electrical and mechanical systems). A robust, easy-to-understand 10-point scoring system was developed to facilitate an unbiased comparison of similar building types across the country. The Asset Score does not rely on a database or specific building baselines to establish a rating. Rather, distributions of energy use intensity (EUI) for various building use types were constructed using Latin hypercube sampling and converted to a series of stepped linear scales to score buildings. A score is calculated based on the modelled source EUI after adjusting for climate. A web-based scoring tool, which incorporates an analytical engine and a simulation engine, was developed to standardize energy modelling and reduce implementation cost. This paper discusses the methodology used to perform several hundred thousand building simulation runs and develop the scoring scales.     

Simulation-based coefficients for adjusting climate impact on energy consumption of commercial buildings

This paper presents a new technique for and the results of normalizing building energy consumption to enable a fair comparison among various types of buildings located near different weather stations across the United States. The method was developed for the U.S. Building Energy Asset Score, a whole-building energy efficiency rating system focusing on building envelope, mechanical systems, and lighting systems. The Asset Score is based on simulated energy use under standard operating conditions. Existing weather normalization methods such as those based on heating and cooling degrees days are not robust enough to adjust all climatic factors such as humidity and solar radiation. In this work, over 1000 sets of climate coefficients were developed to separately adjust building heating, cooling, and fan energy use at each weather station in the United States. This paper also presents a robust, standardized weather station mapping based on climate similarity rather than choosing the closest weather station. This proposed simulated-based climate adjustment was validated through testing on several hundreds of thousands of modeled buildings. Results indicated the developed climate coefficients can adjust the climate variations to enable a fair comparison of building energy efficiency.     

FePt/reduced graphene oxide composites for high capacity hydrogen storage

Here, reduced graphene oxide (rGO) was modified with iron and platinum nanoparticles by solvothermal method. The structural order and textural properties of the graphene based materials were studied by BET, TEM, XRD, TGA and XPS techniques. Hydrogen storage properties of GO, platinum loaded reduced graphene oxide (Pt-rGO), iron loaded reduced graphene oxide (Fe-rGO), and iron platinum loaded reduced graphene oxide (FePt-rGO) have been investigated in the pressure range of 0.05 to atmospheric pressure and at 77 and 87 K. This gives hydrogen adsorption capacities of about 1.2, 2.1, 1.9, and 2.7 wt% at 77 K for GO, Pt-rGO, Fe-rGO, and FePt-rGO, respectively. The isosteric heat of adsorption (Q_st) was investigated as a function of hydrogen uptake at 77 and 87 K over the pressure range of 0.05 to atmospheric pressure. The isosteric heat of adsorption for FePt-rGO (9.2 kJ/mol) was found to be higher than the isosteric heat of adsorption for GO (6.1 kJ/mol) indicating a favorable interaction between hydrogen and surface of the reduced graphene oxide.