A cappuccino is prepared by adding about 50 mL frothing, foaming milk to a cup of espresso. Whole milk is best for foaming and the ideal milk temperature when adding it to the espresso is 65 °C. The espresso itself may be warmer than that. During the heating the milk should not burn, as that would spoil the taste. The best way is to heat the milk slowly while stirring to froth the milk and create foam. But modern cappuccino machines in restaurants do not have time for slow heating. Could we heat the milk by just adding hot water? That’s the question we pose to our high school students first. How many mL of 90 °C hot water would be needed to heat 50 mL of milk from a refrigerator temperature (say 4 °C) to 65 °C? Assume that the specific heat of milk is the same as that of water. Students answer the question on a worksheet and practice their computation skills. The answer: 122 g. This would mean an unacceptable dilution of the milk, 2.5 mL of water for every mL of milk. What would the answer be if we use boiling hot water of 100 °C? Students calculate again, then the answer is 87 g, still an unacceptable dilution. What then? What if we use steam?
Current methods for energy diagnosis in heating, ventilation and air conditioning (HVAC) systems are not consistent with process and instrumentation diagrams (P&IDs) as used by engineers to design and operate these systems, leading to very limited application of energy performance diagnosis in practice. In a previous paper, a generic reference architecture – hereafter referred to as the 4S3F (four symptoms and three faults) framework – was developed. Because it is closely related to the way HVAC experts diagnose problems in HVAC installations, 4S3F largely overcomes the problem of limited application. The present article addresses the fault diagnosis process using automated fault identification (AFI) based on symptoms detected with a diagnostic Bayesian network (DBN). It demonstrates that possible faults can be extracted from P&IDs at different levels and that P&IDs form the basis for setting up effective DBNs. The process was applied to real sensor data for a whole year. In a case study for a thermal energy plant, control faults were successfully isolated using balance, energy performance and operational state symptoms. Correction of the isolated faults led to annual primary energy savings of 25%. An analysis showed that the values of set probabilities in the DBN model are not outcome-sensitive. Link to the formal publication via its DOI https://doi.org/10.1016/j.enbuild.2020.110289
Current symptom detection methods for energy diagnosis in heating, ventilation and air conditioning (HVAC) systems are not standardised and not consistent with HVAC process and instrumentation diagrams (P&IDs) as used by engineers to design and operate these systems, leading to a very limited application of energy performance diagnosis systems in practice. This paper proposes detection methods to overcome these issues, based on the 4S3F (four types of symptom and three types of faults) framework. A set of generic symptoms divided into three categories (balance, energy performance and operational state symptoms) is discussed and related performance indicators are developed, using efficiencies, seasonal performance factors, capacities, and control and design-based operational indicators. The symptom detection method was applied successfully to the HVAC system of the building of The Hague University of Applied Sciences. Detection results on an annual, monthly and daily basis are discussed and compared. Link to the formail publication via its DOI https://doi.org/10.1016/j.autcon.2020.103344
Lightweight, renewable origin, mild processing, and facile recyclability make thermoplastics the circular construction materials of choice. However, in additive manufacturing (AM), known as 3D printing, mass adoption of thermoplastics lags behind. Upon heating into the melt, particles or filaments fuse first in 2D and successively in 3D, realizing unprecedented geometrical freedom. Despite a scientific understanding of fusion, industrial consortium experts are still confronted with inferior mechanical properties of fused weld interfaces in reality. Exemplary is early mechanical failure in patient-specific and biodegradable medical devices based on Corbion’s poly(lactides), and more technical constructs based on Mitsubishi’s poly(ethylene terephthalate), PET. The origin lies in contradictory low rate of polymer diffusion and entangling, and too high rate of crystallization that is needed to compensate insufficient entangling. Knowing that Zuyd University in close collaboration with Maastricht University has eliminated these contradictory time-scales for PLA-based systems, Corbion and Mitsubishi contacted Zuyd with the question to address and solve their problem. In previous research it has been shown that interfacial co-crystallization of alternating depositioned opposite stereo-specific PLA grades resulted in strengthening of the interface. To promote mass adoption of thermoplastics AM industries, the innovation question has been phrased as follows: What is a technically scalable route to induce toughness in additively manufactured thermoplastics? High mechanical performance translates into an intrinsic brittle to tough transition of stereocomplex reinforced AM products, focusing on fused deposition modeling. Taking the professional request on biocompatibility, engineering performance and scalability into account, the strategies in lowering the yield stress and/or increasing the network strength comprise (i) biobased and biocompatible plasticizers for stereocomplexed poly(lactide), (ii) interfacial co-crystallization of intrinsically tough polyester based materials formulations, and (iii) in-situ interfacial transesterification of recycled PET formulations.
To optimize patient care, it is vital to prevent infections in healthcare facilities. In this respect, the increasing prevalence of antibiotic-resistant bacterial strains threatens public healthcare. Current gold standard techniques are based on classical microbiological assays that are time consuming and need complex expensive lab environments. This limits their use for high throughput bacterial screening to perform optimal hygiene control. The infection prevention workers in hospitals and elderly nursing homes underline the urgency of a point-of-care tool that is able to detect bacterial loads on-site in a fast, precise and reliable manner while remaining with the available budgets. The aim of this proposal titled SURFSCAN is to develop a novel point-of-care tool for bacterial load screening on various surfaces throughout the daily routine of professionals in healthcare facilities. Given the expertise of the consortium partners, the point-of-care tool will be based on a biomimetic sensor combining surface imprinted polymers (SIPs), that act as synthetic bacterial receptors, with a thermal read-out strategy for detection. The functionality and performance of this biomimetic sensor has been shown in lab conditions and published in peer reviewed journals. Within this proposal, key elements will be optimized to translate the proof of principle concept into a complete clinical prototype for on-site application. These elements are essential for final implementation of the device as a screening and assessment tool for scanning bacterial loads on surfaces by hospital professionals. The research project offers a unique collaboration among different end-users (hospitals and SMEs), and knowledge institutions (Zuyd University of Applied Sciences, Fontys University of Applied Sciences and Maastricht Science Programme, IDEE-Maastricht University), which guarantees transfer of fundamental knowledge to the market and end-user needs.
The objective of Sustainable Solid Biofuel project is to contribute to a zero-waste and low-carbon emission production of charcoal by evaluating the feasibility and energy efficiency of three different conversion technologies. According to the IEA’s World Energy Outlook 2015 3 billion (more than a third of the global population) use solid biomass as wood, charcoal, or animal waste for cooking and heating1. Charcoal is one of the most widely used of the solid biofuels. In current charcoal production processes the gas stream from pyrolysis are mostly directly released to the environment which wastes energy and causes serious environmental pollution. However, the production of charcoal can be improved to be practiced on a sustainable basis by careful selection of wood or alternative biomass source as wood waste or agricultural residues and further focusing on harvesting strategy and production techniques. In the conversion process it is necessary to increase the energy efficiency while reducing emissions. Further sustainability can be increased by processing the smoke that is exhausted from the kiln, that correspond to roughly one third of the whole biomass. Within the volatile components in the smoke there are chemicals which can be used, for example, as industrial cleaners or wood preservatives and thus one of the environmental drawbacks of charcoal production can be eliminated and turned into another product input. Brazil is the world's largest charcoal producer2 consequently the state of the art of the recearch in this field can be found in Brazil. In this Sustainable Solid Biofuels project one of the leading universities of Brazil, the Universidade Federal de Viçosa (UFV) is joining forces with Avans University of Applied Sciences and two Dutch SMEs Privium B.V. and Charcotec B.V. to carry out the evaluation of the improvements that can be achieved in the energy efficiency.
