Oropharyngeal swab samples were collected from 438 live racing pigeons ( Columba livia), with and without signs of respiratory disease, that were housed in 220 lofts in 3 provinces in the western part of the Netherlands. Polymerase chain reaction (PCR) was used to identify Mycoplasma species and pigeon herpesvirus-1 (PHV-1) from the samples. In 8.6% of the pigeon lofts tested, signs of respiratory disease were present in pigeons at sampling, and in 30.9% of the sampled pigeon lofts, respiratory signs were observed in pigeons during the 6-month period immediately before sampling. A total of 39.8% of tested pigeons (54.5% of tested lofts) were positive for Mycoplasma species, and 30.6% of tested pigeons (48.6% of tested lofts) were positive for PHV-1. In 15.8% of the tested pigeons (26.8% of tested pigeon lofts), coinfection by Mycoplasma species and PHV-1 was identified. The number of pigeon lofts having pigeons coinfected by Mycoplasma species and PHV-1 was higher than that where only one of the infections was identified. Neither the presence of Mycoplasma species, PHV-1, nor the co-occurrence of both infections was significantly associated with signs of respiratory disease.

Vapor compression cycles have gained high importance due to increasing concerns regarding the decarbonization of heating and cooling applications.Typically, vapor compression cycles operate under dynamic conditions, making it difficult to predict their performance accurately. Dynamic simulation models present a decent solution for increasing the reliability of the performance assessment. However, the implementation of dynamic simulation models is a complex task, requiring a uniform description and model development. Therefore, this article introduces an open-source Vapor Compression Library called VCLib based on a literature review of existing libraries for modeling and simulation of vapor compression cycles. The VCLib combines simulation models from the refrigerant through the component to the system level. The simulation models in the VCLib strictly follow a modular and scalable modeling approach. Class diagrams vividly describe the structure of models, making the VCLib easy to use for new users, especially students.

The initial idea of using Lego Mindstorms Robots for student courses had soon to be expanded to a simulation environment as the user base in students grew larger and the need for parallel development and testing arose. An easy to use and easy to set up means of providing positioning data led to the creation of an indoor positioning system so that new users can adapt quickly and successfully, as sensors on the actual robots are difficult to configure and hard to interpret in an environmental context. A global positioning system shared among robots can make local sensors obsolete and still deliver more precise information than currently available sensors, also providing the base necessary for the robots to effectively work on shared tasks as a group. Further more, a simulator for robots programmed with Fujaba and Java which was developed along the way can be used by many developers simultaneously and lets them evaluate their code in a simple way, while close to real-world results.

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The efficiency of heat pump systems is highly dependent on the temperature gap between the sink and the source side. Therefore, it is necessary to accurately model the sink side to enable the most accurate and holistic analysis of building energy systems. In both residential and non-residential buildings, underfloor heating systems are becoming more and more widely used. The use of underfloor heating lowers the flow temperature of the heating system compared to a radiator, which increases the efficiency of a heat pump system. This paper provides an underfloor heating system model including automatic parametrization according to the European standard for surface embedded heating and cooling systems EN 1264. Since the model represents a whole underfloor system, it consists at the system level of the distributor and several heating circuits and takes the heat transfer at the smallest level from a pipe element through different floor layers into account. The model is verified for the system requirements according to European standard EN 1264. A parameter study with a variety of different underfloor heating parameters and floor layers shows that reductions in heat transfer in the underfloor heating system are compensated by an increase in the flow temperature. The highest influence on the temperature level of the system is exerted by the pipe spacing T , which raises the flow temperature by up to 10.9 K, from 36.6°C (T = 100 mm) to 47.5°C