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Highlights: [•] Decorative ethanol fireplaces in domestic appliances significantly increased in recent years. [•] There are different risk sources investigated by experimental and numerical approaches: flash phenomena, burn injuries. [•] The effect of such fireplaces on interior air quality was also investigated. [•] French standards and regulations related to this type of appliances are based on this work. [Copyright &y& Elsevier]

A significant part of the world’s population (about 40%) cooks their meals and provides heating for their homes using wood-burning heating devices. Due to the relatively low cost of fuel and their aesthetic design, solid fuel stoves capable of heat accumulation are convenient and common. The use of dedicated small-scale power generators provides also additional benefits. This paper presents the results of a study conducted to verify the possibility of generating power using stove-fireplaces with heat accumulation systems. In such units, the temperature of the flue gas should be kept at a certain level for the purposes of storing heat, which results from certain limitations of the thermoelectric generators. To verify the possibility of applying thermoelectric modules in such heating devices, a dedicated system with thermoelectric generators was selected from among various microcogeneration systems and implemented. Three types of heat exchangers were studied and the most efficient unit was selected for further testing. Two types of generators, with maximum operating temperatures of 320 and 175 °C, were compared. Subsequently, the characteristics of the latter were determined. The conducted tests allowed to determine the performance and the total efficiency of the generators that were used. It has been demonstrated that the maximum power of the generator would not exceed ca. 30 W e and that there is no economic justification for such a device. However, providing a self-powered and self-sufficient operation of stove-fireplaces with heat accumulation systems remains an important goal. [ABSTRACT FROM AUTHOR]

The existence of fire/hearths at Upper Palaeolithic sites is highly expected due to the cold glacial climate. However, fireplaces/hearths are missing at several Late Upper Palaeolithic Moravian (Czech Republic) sites. Here we discuss the possibilities of how to identify the presence of fire at archaeological sites using indirect methods. Our analysis focused on both potentially heated/burned artefacts and spatial distribution of fireplaces from within four Moravian (Czech Republic) sites. Colour and magnetic measurements may be indicative of heated cherts/flint recognition but macroscopic visual observation remains key for such estimations. Concerning the distribution of hearths within the four analysed sites, only Brno-Štýřice III site seems to have witnessed little post-depositional disturbance of its anthropogenic sediments and, at the same time, shows a good correlation of presumed fireplaces with the distribution of heated artefacts. [ABSTRACT FROM AUTHOR]

The paper presents quantitative approach for management decisions of the manufacturing system for production of fireplaces, related to evaluation of key parameters - productivity and throughput, which most authors and methodologies consider to be substantial. Methodology was based on creating the simulation model of the fireplace production line in software Witness; optimizing the production capacity by selecting constraints, based on results from simulation model; evaluating the simulation experiments with the goal to increase productivity; setting production to maximize sales profits using Simplex method. Simulation model was built according to a technological process of fireplaces in a semi-automated production. Improvement in a production process within theory of constraints philosophy is complemented by mathematical modelling - Simplex method, that estimate profit maximization in case the company management decides to produce more product variants. [ABSTRACT FROM AUTHOR]

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In light of the enculturation of landscapes by ethnographically documented hunter-gatherers, we should expect Mesolithic hunter-gatherers to have endowed their early Holocene landscapes with meaning. Attempts to find evidence for this have focussed on the unusual and exotic – those aspects of the archaeological record that seem immediately unrelated to subsistence. In this contribution, I suggest that fireplaces, ubiquitous on Mesolithic sites and often swiftly passed over in site reports as evidence for cooking alone, had played a key role in the process of landscape enculturation. Although we cannot reconstruct the specific meanings once attached to early Holocene landscapes, by appreciating the social and cultural significance of fireplaces we gain a more holistic view of the Mesolithic than is currently the case, whether in those studies that focus on settlement and subsistence or those that cite examples of ritual. In the course of making this argument, I summarise the evidence for fireplaces from Mesolithic Britain, noting the need for more systematic reporting. Finally, I provide a case study from western Scotland that seeks to view a suite of fireplaces in the context of the landscape topography, early Holocene environments, subsistence economy, and by drawing on selected ethnographic analogies. [ABSTRACT FROM AUTHOR]

An essay is presented on the comments of Swedish-Finnish naturalist Peter Kalm on energy use in Pennsylvania in mid-18th century including his observations of the Delaware Valley region. Kalm argues that trees and plants that withstand the winter in the state should be similar in Sweden. He argues against colonists' extravagant use of firewood on their open fireplaces. Also discussed is the Hopewell Furnace National Historic Site, which operates from 1771-1883.

Article presents usage of fireplaces with a water jacket and with an air turbine in a single-family detached home. Influence of usage of fireplaces on primary energy demand was also analysed.

Compact and highly performing photonic devices are characterized by non-intuitive geometries, a large number of parameters, and multiple figures of merit. Optimization and machine learning techniques have been explored to handle these complex designs, but the existing approaches often overlook stochastic quantities. As an example, random fabrication uncertainties critically determines experimental device performance. Here, we present a novel approach for the stochastic multi-objective design of photonic devices combining unsupervised dimensionality reduction and Gaussian process regression. The proposed approach allows to efficiently identify promising alternative designs and model the statistic of their response. Incorporating both deterministic and stochastic quantities into the design process enables a comprehensive analysis of the device and of the possible trade-offs between different performance metrics. As a proof-of-concept, we investigate surface gratings for fiber coupling in a silicon-on-insulator platform, considering variability in structure sizes, silicon thickness, and multi-step etch alignment. We analyze 86 alternative designs presenting comparable performance when neglecting variability, discovering on the contrary marked differences in yield and worst-case figures for both fiber coupling efficiency and back-reflections. Pareto frontiers demonstrating optimized device robustness are identified as well, offering a powerful tool for the design and optimization of photonic devices with stochastic figures of merit. [ABSTRACT FROM AUTHOR]

Mode division multiplexing (MDM) is currently one of the most attractive multiplexing techniques in optical communications, as it allows for an increase in the number of channels available for data transmission. Optical modal converters are one of the main devices used in this technique. Therefore, the characterization and improvement of these devices are of great current interest. In this work, we present a dataset of 49,736 near-field intensity images of a modal converter based on a long-period fiber grating (LPFG) written on a few-mode fiber (FMF). This characterization was performed experimentally at various wavelengths, polarizations, and temperature conditions when the device converted from LP 01 mode to LP 11 mode. The results show that the modal converter can be tuned by adjusting these parameters, and that its operation is optimal under specific circumstances which have a great impact on its performance. Additionally, the potential application of the database is validated in this work. A modal decomposition technique based on the particle swarm algorithm (PSO) was employed as a tool for determining the most effective combinations of modal weights and relative phases from the spatial distributions collected in the dataset. The proposed dataset can open up new opportunities for researchers working on image segmentation, detection, and classification problems related to MDM technology. In addition, we implement novel artificial intelligence techniques that can help in finding the optimal operating conditions for this type of device. [ABSTRACT FROM AUTHOR]