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Between 2019 and 2022, the team of the Kurdish-Italian Faida Archaeological Project (KIFAP) found thirteen Assyrian rock reliefs in Faida, Northern Iraqi Kurdistan. The archaeological mission was conducted by Professor Daniele Morandi Bonacossi from the Department of Humanities and Cultural Heritage (DIUM) of the University of Udine together with the Directorate of Antiquities of Duhok. The finding of the first ten rock reliefs of the VIII Century BC earned the title of the most important archaeological discovery of 2019, winning the prestigious 2022 International Archaeological Discovery Award Khaled al-Asaad. Four years later, on October 16th, 2022, the Faida Archaeological Park was officially opened, the first of its kind in Iraq.

Precise indoor localization of moving targets is a challenging activity which cannot be easily accomplished without combining different sources of information. In this sense, the combination of different data sources with an appropriate filter might improve both positioning and tracking performance. This work proposes an algorithm for hybrid positioning in Wireless Sensor Networks based on data fusion of UWB and inertial information. A constant-gain Steady State Kalman Filter is used to bound the complexity of the system, simplifying its implementation on a typical low-power WSN node. The performance of the presented data fusion algorithm has been evaluated in a realistic scenario using both simulations and realistic datasets. The obtained results prove the validity of this approach, which efficiently fuses different positioning data sources, reducing the localization error.

Dual fuel combustion has gained attention as a cost-effective solution for reducing the pollutant emissions of internal combustion engines. The typical approach is combining a conventional high-reactivity fossil fuel (diesel fuel) with a sustainable low-reactivity fuel, such as bio-methane, ethanol, or green hydrogen. The last one is particularly interesting, as in theory it produces only water and NOx when it burns. However, integrating hydrogen into stock diesel engines is far from trivial due to a number of theoretical and practical challenges, mainly related to the control of combustion at different loads and speeds. The use of 3D-CFD simulation, supported by experimental data, appears to be the most effective way to address these issues. This study investigates the hydrogen-diesel dual fuel concept implemented with minimum modifications in a light-duty diesel engine (2.8 L, 4-cylinder, direct injection with common rail), considering two operating points representing typical partial and full load conditions for a light commercial vehicle or an industrial engine. The numerical analysis explores the effects of progressively replacing diesel fuel with hydrogen, up to 80% of the total energy input. The goal is to assess how this substitution affects engine performance and combustion characteristics. The results show that a moderate hydrogen substitution improves brake thermal efficiency, while higher substitution rates present quite a severe challenge. To address these issues, the diesel fuel injection strategy is optimized under dual fuel operation. The research findings are promising, but they also indicate that further investigations are needed at high hydrogen substitution rates in order to exploit the potential of the concept.

A significant challenge in utilizing hydrogen in conventional internal combustion engines is achieving a balance between NOx emissions and brake power output. A lean premixed charge (Lambda ≈ 2.5) allows for efficient and stable combustion with minimal NOx emissions. However, this comes at the cost of reduced power density due to the higher air requirements of the thermodynamic process. While supercharging can mitigate this drawback, it introduces increased complexity, cost, and size. An intriguing alternative is the 2-stroke cycle, particularly in an opposed piston (OP) configuration. This study presents the virtual development of a single-cylinder 2-stroke OP engine with a total displacement of 0.95 L, designed to deliver 25 kW at 3000 rpm. Thanks to its compact size, high thermal efficiency, robustness, modularity, and low manufacturing cost, this engine is intended for use either as an industrial power unit or in combination with electric motors in hybrid vehicles. The overarching goal of this project is to demonstrate that internal combustion engines can offer a practical and cost-effective alternative to hydrogen fuel cells without significant penalties in terms of efficiency and pollutant emissions. The design of this novel engine started from scratch, and both 1D and 3D CFD simulations were employed, with particular focus on optimizing the cylinder’s geometry and developing an efficient low-pressure injection system. The numerical methodology was based on state-of-the-art commercial codes, in line with established engineering practices. The numerical results indicated that the optimized engine configuration slightly surpasses the target performance, achieving 29 kW at 3000 rpm, while maintaining near-zero NOx emissions (<20 ppm) and high brake thermal efficiency (~40%) over a wide power range. Additionally, the cost of this engine is projected to be lower than an equivalent 4-stroke engine, due to fewer components (e.g., no cylinder head, poppet valves, or camshafts) and a lighter construction.

Biomass-derived humins produced in the biorefining of biomass represent an attractive feedstock for thermochemical processes. This work examines the purification and characterization of humins derived from sugarcane bagasse and rice husks (H-SCB and H-RH, respectively), followed by the kinetic and thermodynamic analysis of its pyrolysis. Pyrolysis was assessed via thermogravimetric analysis, and a global reaction model was adopted to address pyrolysis kinetics. To boost the quality of fit between the kinetic model and thermoanalytical data, the analyses are based on Vyazovkin's method. The activation energy of H-SCB increased from 166.09 to 329.76 kJ mol−1. In contrast, the activation energy of H-RH decreased from 163.31 to 84.99 kJ mol−1. According to the results of the generalized master-plot approach, the governing reaction mechanism shifted among order-based models, nucleation, and diffusion-controlled particle mechanisms. Thermodynamic properties showed that the process is endothermic, with the thermal decomposition of H-SCB being more reactive (ΔSaverage = -0.004 kJ mol−1 K−1) compared to H-RH (ΔSaverage = -0.05 kJ mol−1 K−1). Also, the heat absorbed helps the humins to achieve a more ordered state close to a conversion of 0.50. Furthermore, a difference of about 7 kJ mol−1 between the enthalpy of the reaction and the average activation energy indicates the formation of favorable product with humins’ considerable bioenergy potential. These findings are the first reported data on the forecast kinetic curves and pyrolysis mechanism of biorefinery-derived humins, and these results will enable process design for the thermochemical conversion of these emerging materials to produce energy and other products.

The numerical study presented in this article is based on an automotive diesel engine (2.8 L, 4-cylinder, turbocharged), considering a NG–H₂ blend with 30 vol% of H₂, ignited by multiple diesel fuel injections. The 3D-CFD investigation aims at improving BTE, CO, and UHC emissions at low load, by means of an optimization of the diesel fuel injection strategy and of the in-cylinder turbulence (swirl ratio, SR). The operating condition is 3000 rpm – BMEP = 2 bar, corresponding to about 25% of the maximum load of a gen-set engine, able to deliver up to 83 kW at 3000 rpm (rated speed). The reference diesel fuel injection strategy, adopted in all the previous numerical and experimental studies, is a three-shot mode. The numerical optimization carried out in this study consisted in finding the optimal number of injections per cycle, as well as the best timing of each injection and the fuel mass split among the injections. The analysis revealed that combustion can be improved by increasing the local concentration of the more reactive fuel (diesel): in detail, the best strategy is a two-shot mode, with SOI1 = −35°CA AFTDC and SOI2 = −20°CA AFTDC, injecting 70% of the total diesel fuel mass at the first shot. As far as the SR is concerned, the best compromise between performance and emissions was found for a relatively low SR = 1.4. The optimization permitted to extract the full potential of the H₂ enrichment in the DF H₂/NG–diesel combustion also at low loads: in comparison to the DF NG case, combustion efficiency, and gross indicated thermal efficiency have been improved by 45.7% and 61.0%, respectively; CO- and UHC-specific emissions have been reduced by about 85.0%. Comparing CDC to the optimized DF 30 vol% H₂/NG–diesel case, soot emissions are completely canceled, CO₂-specific emissions have been reduced by approximately 42.0%, NOₓ-specific emissions by 33.8%. However, further work has to be done in order to reach comparable values of HC and CO, which are still higher than in a standard diesel combustion.

Rape-seed biodiesel is an interesting option to address the problem of decreasing availability of conventional fossil fuels, as well as to reduce the CO2 emissions of internal combustion engines. The present paper describes an experimental campaign carried out on a current production 4-cylinder, 4-stroke naturally aspirated diesel engine, running on standard diesel fuel and on three different blends of rape-seed biodiesel (20%-50%-100%). Performance, emissions and in-cylinder pressure traces were measured at full load. It was found that the influence of rape-seed biodiesel in the fuel blend is not constant at each operating condition. However, as the biodiesel content increases, full load performance tends to drop, in particular brake specific fuel consumption (maximum worsening: +18%), while soot emission goes down. The maximum improvement observed in terms of soot concentration is 37.5%, at 1200 rpm. The combustion analysis revealed that the main differences among the fuels occur in the first phase of combustion: the burn rate is slower for biodiesel blends at low speeds, and faster at high.

The goal of this study is to develop a clean and efficient thermal unit for a generator set (gen-set) rated at 80 kW, exploring the potential of Dual-Fuel (DF) combustion (Natural Gas-Diesel) on high-speed Compression Ignition (CI) engines. Typically, the most comparable commercial gen-sets are made up of Heavy-Duty (HD) Diesel engines, whose cost and complexity will probably increase to meet more stringent emissions standards. The conversion of a light-duty Diesel engine may permit to match the high efficiency of Diesels with the low emissions of DF combustion at an affordable cost. Moreover, the new thermal unit would be more compact and lighter. Running on Natural Gas (NG) is less expensive than using Diesel fuel, and it offers more opportunities to reduce the environmental impact (e.g., NG can be easily obtained from biomass, in the same site where the gen-set is installed). Last but not the least, in case of interruption of NG supply, the system can be easily switched to conventional Diesel operation, offering a higher fuel flexibility. Despite the large number of scientific publications concerning DF engines, very few of them consider high-speed units equipped with modern Common Rail injection systems. Even more limited are the investigations on the combustion process at medium-high loads (BMEP > 10 bar), carried out by measuring in-cylinder pressure and optimizing all the fundamental control parameters (injection strategy for both Diesel fuel and NG, boost pressure, EGR rates, etc.). It should be observed that the use of state-of-the-art injection systems and the accurate calibration of their parameters at each operating condition is the only way to maximize the benefits of NG in terms of reduction of soot emissions while addressing the well-known issues related to the increase of some pollutants (HC, CO, and NOₓ). This study reviews the results of a theoretical and experimental activity carried out on a four-cylinder, Common Rail, 2.8-liter turbocharged Diesel engine. A gas injection system is installed upstream of the intake plenum, and an open Electronic Control Unit (ECU) is used to calibrate all the most important engine parameters. Thanks to the deep insight into the combustion process provided by in-cylinder pressure analysis and measurement of pollutant emissions, the study presents some general guidelines for setting the control strategy in this type of DF engine. Considering the operating condition at maximum power (BMEP = 12 bar, 3000 rpm, brake power = 83 kW), the following advantages are observed with comparison to the standard Diesel engine: soot is more than halved, NOₓ emissions are reduced by 32% and CO₂ by 31%, and Brake Thermal Efficiency (BTE) increases from 35.8% to 39%. The only drawback is the increase of one order of magnitude of both CO and HC, requiring a specific oxidation catalyst. Another outcome of the study is the limitation on the use of DF NG-Diesel combustion at low loads: the experimental activity demonstrates that it is very difficult to achieve complete combustion of an ultra-lean air-NG premixed charge so that BTE tends to drop. At these conditions, it appears to be more convenient to switch back to standard Diesel operations.

A high prevalence of vitamin D deficiency (VDD) in children has been observed worldwide, but there are few studies on the nutritional status of vitamin D (VD) in healthy infants. The main cause of deficiency in healthy children is breastfeeding without supplementation and lack or insufficiency of sun exposure. The aims of this study were to determine serum concentrations of 25(OH)D and verify its association with parathyroid hormone (PTH) concentrations and use of VD supplementation in healthy infants aged ≥ 6 to ≤ 24 months attended at two Primary Health Care Units in Ribeirão Preto city, São Paulo, Brazil. A cross-sectional, observational and analytical study was performed in which serum concentrations of 25(OH)D, PTH, alkaline phosphatase (AP), calcium (Ca), phosphorus (P) and albumin were determined in 155 healthy infants. Information on sun exposure, sociodemographic aspects of mothers and clinical and nutritional characteristics of infants were obtained through interviews with responsible infants's legal representatives. Ten infants (6%) presented deficient 25(OH)D serum concentration (≤20ng/ml) and 46 (30%), insufficient (21 to 29ng/ml). No changes in serum P, Ca and albumin concentrations were detected. Only one infant had an increase in PTH serum concentrations. 35% (55/155) of infants had high AP e 40% (22/55) presented insufficient serum concentrations of 25(OH)D but none presented deficient ones. There was a weak association between serum concentrations of 25(OH)D and PTH and an association between serum concentrations of 25(OH)D and P when adjusted for sex, age and BMI. There were no associations between inadequate serum concentrations of 25(OH)D (deficient ou insufficient), sun exposure and VD supplementation. This study found a low prevalence of deficient 25(OH)D serum concentration and high prevalence of insufficient ones which was not associated with changes in serum PTH, AP, P, Ca and albumin concentrations, VD supplementation and the formula volume intake.

Objectives To analyse intake of vitamin A (VA) and retinol concentrations in maternal blood, breast milk (BM), and the umbilical cord (UC) of newborns, and to determine the associations among these variables. Methods We performed a cross-sectional, epidemiological study of 180 mother–newborn dyads. Maternal and UC blood samples and BM were collected. VA intake by the mother over 30 days was assessed using a questionnaire. Results Mean retinol concentrations in maternal serum, the UC, and BM were 0.65 ± 0.27, 0.36 ± 0.18, and 2.95 ± 2.70 µmol/L, respectively. Retinol concentrations <0.70 µmol/L were found in 57.2% of maternal blood samples and in 94.9% of UC samples. A total of 27.9% of BM samples showed retinol concentrations <1.05 µmol/L. Mean VA intake by the mothers was 1041.33 ± 1187.86 µg retinol activity equivalents/day and was inadequate (<550 µg retinol activity equivalents/day) in 44.7%. Conclusions High proportions of insufficient retinol concentrations were observed in the UC, maternal blood, and BM. A high percentage of pregnant women had inadequate VA intake. Mothers with insufficient serum retinol concentrations had newborns with lower retinol concentrations in the UC. Higher retinol concentrations were observed in maternal blood and the UC with a higher VA intake.