Journal articles: 'Graph burning'

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García-Díaz, Jesús, Lil María Xibai Rodríguez-Henríquez, Julio César Pérez-Sansalvador, and Saúl Eduardo Pomares-Hernández. "Graph Burning: Mathematical Formulations and Optimal Solutions." Mathematics 10, no. 15 (August 5, 2022): 2777. http://dx.doi.org/10.3390/math10152777.

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The graph burning problem is an NP-hard combinatorial optimization problem that helps quantify how vulnerable a graph is to contagion. This paper introduces three mathematical formulations of the problem: an integer linear program (ILP) and two constraint satisfaction problems (CSP1 and CSP2). Thanks to off-the-shelf optimization software, these formulations can be solved optimally over arbitrary graphs; this is relevant because the only algorithms designed to date for this problem are approximation algorithms and heuristics, which do not guarantee to find optimal solutions. We empirically compared the proposed formulations using random graphs and off-the-shelf optimization software. The results show that CSP1 and CSP2 tend to reach optimal solutions in less time than the ILP. Therefore, we executed them over some benchmark graphs of order at most 5908. The previously best-known solutions for some of these graphs were improved. We draw some empirical observations from the experimental results. For instance, we find the tendency: the larger the graph’s optimal solution, the more difficult it is to find it. Finally, the resulting set of optimal solutions might be helpful as a benchmark dataset for the performance evaluation of non-exact algorithms.

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Mitsche, Dieter, Paweł Prałat, and Elham Roshanbin. "Burning number of graph products." Theoretical Computer Science 746 (October 2018): 124–35. http://dx.doi.org/10.1016/j.tcs.2018.06.036.

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Bessy, Stéphane, Anthony Bonato, Jeannette Janssen, Dieter Rautenbach, and Elham Roshanbin. "Burning a graph is hard." Discrete Applied Mathematics 232 (December 2017): 73–87. http://dx.doi.org/10.1016/j.dam.2017.07.016.

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Tan, Ta Sheng, and Wen Chean Teh. "Graph burning: Tight bounds on the burning numbers of path forests and spiders." Applied Mathematics and Computation 385 (November 2020): 125447. http://dx.doi.org/10.1016/j.amc.2020.125447.

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Khakzad, Nima. "A Graph Theoretic Approach to Optimal Firefighting in Oil Terminals." Energies 11, no. 11 (November 9, 2018): 3101. http://dx.doi.org/10.3390/en11113101.

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Effective firefighting of major fires in fuel storage plants can effectively prevent or delay fire spread (domino effect) and eventually extinguish the fire. If the number of firefighting crew and equipment is sufficient, firefighting will include the suppression of all the burning units and cooling of all the exposed units. However, when available resources are not adequate, fire brigades would need to optimally allocate their resources by answering the question “which burning units to suppress first and which exposed units to cool first?” until more resources become available from nearby industrial plants or residential communities. The present study is an attempt to answer the foregoing question by developing a graph theoretic methodology. It has been demonstrated that suppression and cooling of units with the highest out-closeness index will result in an optimum firefighting strategy. A comparison between the outcomes of the graph theoretic approach and an approach based on influence diagram has shown the efficiency of the graph approach.

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Chen, Jiahui, Yi Yang, Ling Peng, Luanjie Chen, and Xingtong Ge. "Knowledge Graph Representation Learning-Based Forest Fire Prediction." Remote Sensing 14, no. 17 (September 3, 2022): 4391. http://dx.doi.org/10.3390/rs14174391.

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Forest fires destroy the ecological environment and cause large property loss. There is much research in the field of geographic information that revolves around forest fires. The traditional forest fire prediction methods hardly consider multi-source data fusion. Therefore, the forest fire predictions ignore the complex dependencies and correlations of the spatiotemporal kind that usually bring valuable information for the predictions. Although the knowledge graph methods have been used to model the forest fires data, they mainly rely on artificially defined inference rules to make predictions. There is currently a lack of a representation and reasoning methods for forest fire knowledge graphs. We propose a knowledge-graph- and representation-learning-based forest fire prediction method in this paper for addressing the issues. First, we designed a schema for the forest fire knowledge graph to fuse multi-source data, including time, space, and influencing factors. Then, we propose a method, RotateS2F, to learn vector-based knowledge graph representations of the forest fires. We finally leverage a link prediction algorithm to predict the forest fire burning area. We performed an experiment on the Montesinho Natural Park forest fire dataset, which contains 517 fires. The results show that our method reduces mean absolute deviation by 28.61% and root-mean-square error by 53.62% compared with the previous methods.

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Данилов, I. Danilov, Попова, and I. Popova. "IMPROVEMENT AND CALCULATION OF TRAFFIC SIGNAL CYCLE TO REDUCE CONGESTION BY USING A PHASE COEFFICIENT." Alternative energy sources in the transport-technological complex: problems and prospects of rational use of 3, no. 1 (March 16, 2016): 298–301. http://dx.doi.org/10.12737/17768.

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The article describes the method of calculating the optimum values of the traffic light phase, which will minimize traffic congestion. Conditions of occurrence of traffic jams were analyzed. A graph of the phase factor of the burning time of traffic light was composed

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Šimon, Marek, Ladislav Huraj, Iveta Dirgová Luptáková, and Jiří Pospíchal. "Heuristics for Spreading Alarm throughout a Network." Applied Sciences 9, no. 16 (August 9, 2019): 3269. http://dx.doi.org/10.3390/app9163269.

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This paper provides heuristic methods for obtaining a burning number, which is a graph parameter measuring the speed of the spread of alarm, information, or contagion. For discrete time steps, the heuristics determine which nodes (centers, hubs, vertices, users) should be alarmed (in other words, burned) and in which order, when afterwards each alarmed node alarms its neighbors in the network at the next time step. The goal is to minimize the number of discrete time steps (i.e., time) it takes for the alarm to reach the entire network, so that all the nodes in the networks are alarmed. The burning number is the minimum number of time steps (i.e., number of centers in a time sequence alarmed “from outside”) the process must take. Since the problem is NP complete, its solution for larger networks or graphs has to use heuristics. The heuristics proposed here were tested on a wide range of networks. The complexity of the heuristics ranges in correspondence to the quality of their solution, but all the proposed methods provided a significantly better solution than the competing heuristic.

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Liu, Yangxun, Weinan Liu, Huihong Liao, Hasier Ashan, Wenhua Zhou, and Cangsu Xu. "An Experimental and a Kinetic Modelling Study of Ethanol/Acetone/Ethyl Acetate Mixtures." Energies 15, no. 9 (April 20, 2022): 2992. http://dx.doi.org/10.3390/en15092992.

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With the world’s energy resources decreasing, ethanol/acetone/ethyl acetate mixed fuel has the potential as a fossil fuel alternative or oxygenated fuel additive. In this work, the burning characteristics of ethanol/acetone/ethyl acetate mixed fuels including 3 pure fuels, 9 binary fuels, and 7 ternary fuels were studied at a temperature of 358 K, the pressure of 1 bar, and the equivalence ratios of 0.7 to 1.4 in the constant volume combustion chamber (CVCC). The burning velocities of the ternary fuels were compared at ϕ = 0.8, 1.0, and 1.4. The results show that the laminar burning velocities of the mixed fuels are affected by the contents of ethanol, acetone, and ethyl acetate. The Markstein length, Markstein number, and burning flux were also analyzed in this paper. Furthermore, a detailed chemical mechanism comprising 506 species and 2809 reactions was reduced to a skeletal mechanism including 98 species and 642 reactions, using the directed relation graph with error propagation (DRGEP). The experimental and the simulated laminar burning velocities were compared. The results of laminar burning velocities show that the relative deviation of ETEAAC 112 is approximately 17.5%. The sensitivity coefficients, flame structure, and reaction paths of ethyl acetate were investigated with the skeletal and the detailed mechanisms. It is found that the key reaction path is retained in the skeletal mechanism.

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Hu, Xiaoxue, Jiacheng Hu, and Jiangxu Kong. "The Surviving Rate of IC-Planar Graphs." Symmetry 14, no. 6 (June 17, 2022): 1258. http://dx.doi.org/10.3390/sym14061258.

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Let k and n be two positive integers. Firefighting is a discrete dynamical process of preventing the spread of fire. Let G be a connected graph G with n vertices. Assuming a fire starts at one of the vertices of G, the firefighters choose k unburned vertices at each step, and then the fire spreads to all unprotected neighbors of the burning vertices. The process continues until the fire stops spreading. The goal is to protect as many vertices as possible. When a fire breaks out randomly at a vertex of G, its k-surviving rate, ρk(G), is the expected number of saved vertices. A graph is IC-planar if it has a drawing in which each edge cross once and their endpoints are disjoint. In this paper, we prove that ρ4(G)>1124 for every IC-planar graph G. This is proven by the discharging method and the locally symmetric of the graph.

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Chebotarev, Victor I., Anastasia P. Pirozhnikova, and Alla V. Koroleva. "Graph-Analytical Estimation Method of Natural Ventilation Efficiency during Natural Gas Combustion." Materials Science Forum 931 (September 2018): 901–4. http://dx.doi.org/10.4028/www.scientific.net/msf.931.901.

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Open burning of natural gas when using gas equipment in the premises of residential buildings is considered, taking into account the formation of combustion products, depending on the coefficients of excess air. Theoretical and experimental studies of combustion processes are presented. To determine the aerodynamic process in the ventilation duct, theoretical calculations of the dependence of the discharge at the entrance to the ventilation duct from the outside temperature of the atmospheric air were made. Graph-analytic method of evaluating the effectiveness of natural ventilation is carried out.

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Liu, Yangxun, Weinan Liu, Huihong Liao, Wenhua Zhou, and Cangsu Xu. "An Experimental and Kinetic Modelling Study on Laminar Premixed Flame Characteristics of Ethanol/Acetone Mixtures." Energies 14, no. 20 (October 15, 2021): 6713. http://dx.doi.org/10.3390/en14206713.

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Since both ethanol and acetone are the main components in many alternative fuels, research on the burning characteristics of ethanol-acetone blends is important to understand the combustion phenomena of these alternative fuels. In the present study, the burning characteristics of ethanol-acetone fuel blends are investigated at a temperature of 358 K and pressure of 0.1 MPa with equivalence ratios ranging from 0.7 to 1.4. Ethanol at 100% vol., 25% vol. ethanol/75% vol. acetone, 50% vol. ethanol/50% vol. acetone, 75% vol. ethanol/25% vol. acetone, and 100% vol. acetone are studied by the constant volume combustion chamber (CVCC) method. The results show that the laminar burning velocities of the fuel blends are between that of 100% vol. acetone and 100% vol. ethanol. As the ethanol content increases, the laminar burning velocities of the mixed fuels increase. Furthermore, a detailed chemical kinetic mechanism (AramcoMech 3.0) is used for simulating the burning characteristics of the mixtures. The directed relation graph (DRG), DRG with error propagation (DRGEP), sensitivity analysis (SA), and full species sensitivity analysis (FSSA) are used for mechanism reduction. The flame structure of the skeletal mechanism does not change significantly, and the concentration of each species remains basically the same value after the reaction. The numbers of reactions and species are reduced by 90% compared to the detailed mechanism. Sensitivity and reaction pathway analyses of the burning characteristics of the mixtures indicate that the reaction C2H2+H(+M)<=>C2H3(+M) is the key reaction.

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Zhou, Jun-mei, Fang Wei, Su-jun Liu, and Bi-meng Zhang. "Study on burning temperature versus time graph of moxa sticks in a novel animal moxibustion device." Journal of Acupuncture and Tuina Science 12, no. 3 (May 30, 2014): 194–98. http://dx.doi.org/10.1007/s11726-014-0772-z.

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Zhirnov, Andrey A., Konstantin V. Stepanov, Stanislav G. Sazonkin, Tatyana V. Choban, Kirill I. Koshelev, Anton O. Chernutsky, Alexey B. Pnev, Alexey O. Novikov, and Dmitriy A. Yagodnikov. "Study of Intra-Chamber Processes in Solid Rocket Motors by Fiber Optic Sensors." Sensors 21, no. 23 (November 25, 2021): 7836. http://dx.doi.org/10.3390/s21237836.

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In this study, an experimental study of the burning rate of solid fuel in a model solid propellant rocket motor (SRM) E-5-0 was conducted using a non-invasive control method with fiber-optic sensors (FOSs). Three sensors based on the Mach–Zehnder interferometer (MZI), fixed on the SRM E-5-0, recorded the vibration signal during the entire cycle of solid fuel burning. The results showed that, when using MZI sensors, the non-invasive control of solid fuel burnout is made possible both by recording the time of arrival of the combustion front to the sensor and by analyzing the peaks on the spectrogram of the recorded FOS signal. The main mode of acoustic vibrations of the chamber of the model SRM is longitudinal, and it changes with time, depending on the chamber length. Longitudinal modes of the combustion chamber were detected by MZI only after the combustion front passed its fixing point, and the microphone was unable to register them at all. The results showed that the combustion rate was practically constant after the first second, which was confirmed by the graph of the pressure versus time at the nozzle exit.

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Gohil, Vikram B., Adhish V. Vyas, and Dodiya Kinjal K. "A prospective study of uroflowmetry in 100 patients with lower urinary tract symptoms." International Surgery Journal 6, no. 10 (September 26, 2019): 3762. http://dx.doi.org/10.18203/2349-2902.isj20194438.

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Background: Uroflowmetry is diagnostic procedure of various urinary tract diseases like urethral stricture, benign prostatic hyperplasia, neurogenic bladder, detrusor muscle overactivity by calculating the rate of urine expulsion against the time unit in second. Uroflowmetry is simple and non-invasive diagnostic method.Methods: This is a prospective study of 100 cases which fulfil inclusion and exclusion criteria. After taking informed written consent of the patients, they have gone under uroflowmetry study by Urocap 3 uroflowmeter, and graphs were obtained and result analysed.Results: Maximum number of patients has prolonged curve graph were diagnosed as benign prostate hypertrophy (BPH) (53%), dysfunctional voiding curve for detrusor overactivity (20%) intermittent flow curve for neurogenic bladder (7%), Box variety for urethral stricture (7%).Conclusions: In present study we found that uroflowmetry is helpful in diagnosis of certain urological pathologies. Common lower urinary symptoms were burning micturition, frequency and difficulty in micturition. Age group from 50-70 years was often presented with bladder outflow obstruction. Uroflowmetry overall useful in diagnosis of BPH and urethral stricture which can be supported by ultrasonography of prostate with PVRV and RGU respectively to avoid other invasive and more difficult pressure or flow urodynamic study.

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Rettelbach, Tabea, Moritz Langer, Ingmar Nitze, Benjamin Jones, Veit Helm, Johann-Christoph Freytag, and Guido Grosse. "A Quantitative Graph-Based Approach to Monitoring Ice-Wedge Trough Dynamics in Polygonal Permafrost Landscapes." Remote Sensing 13, no. 16 (August 5, 2021): 3098. http://dx.doi.org/10.3390/rs13163098.

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In response to increasing Arctic temperatures, ice-rich permafrost landscapes are undergoing rapid changes. In permafrost lowlands, polygonal ice wedges are especially prone to degradation. Melting of ice wedges results in deepening troughs and the transition from low-centered to high-centered ice-wedge polygons. This process has important implications for surface hydrology, as the connectivity of such troughs determines the rate of drainage for these lowland landscapes. In this study, we present a comprehensive, modular, and highly automated workflow to extract, to represent, and to analyze remotely sensed ice-wedge polygonal trough networks as a graph (i.e., network structure). With computer vision methods, we efficiently extract the trough locations as well as their geomorphometric information on trough depth and width from high-resolution digital elevation models and link these data within the graph. Further, we present and discuss the benefits of graph analysis algorithms for characterizing the erosional development of such thaw-affected landscapes. Based on our graph analysis, we show how thaw subsidence has progressed between 2009 and 2019 following burning at the Anaktuvuk River fire scar in northern Alaska, USA. We observed a considerable increase in the number of discernible troughs within the study area, while simultaneously the number of disconnected networks decreased from 54 small networks in 2009 to only six considerably larger disconnected networks in 2019. On average, the width of the troughs has increased by 13.86%, while the average depth has slightly decreased by 10.31%. Overall, our new automated approach allows for monitoring ice-wedge dynamics in unprecedented spatial detail, while simultaneously reducing the data to quantifiable geometric measures and spatial relationships.

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Saba, Tanzila, Amjad Rehman, Khalid Haseeb, Saeed Ali Bahaj, and Gwanggil Jeon. "Energy-Efficient Edge Optimization Embedded System Using Graph Theory with 2-Tiered Security." Electronics 11, no. 18 (September 16, 2022): 2942. http://dx.doi.org/10.3390/electronics11182942.

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The development of the Internet of Things (IoT) network has greatly benefited from the expansion of sensing technologies. These networks interconnect with wireless systems and collaborate with other devices using multi-hop communication. Besides data sensing, these devices also perform other operations such as compression, aggregation, and transmission. Recently, many solutions have been proposed to overcome the various research challenges of wireless sensor networks; however, energy efficiency with optimized intelligence is still a burning research problem that needs to be tackled. Thus, this paper presents an energy-efficient enabled edge optimization embedded system using graph theory for increasing performance in terms of network lifetime and scalability. First, minimum spanning trees are extracted using artificial intelligence techniques to improve the embedded system for response time and latency performance. Second, the extracted routes are provided with full protection against anonymous access in a two-tiered system. Third, the IoT systems collaborate with mobile sinks, and they need to be authenticated using lightweight techniques for the involvement in routing sensed information. Moreover, edge networks further provide the timely delivery of data to mobile sinks with less overhead on IoT devices. Finally, the proposed system is verified using simulations, revealing its significance to existing approaches.

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Wada, Akihiko, Takashi Shizukuishi, Junko Kikuta, Haruyasu Yamada, Yusuke Watanabe, Yoshiki Imamura, Takahiro Shinozaki, Ko Dezawa, Hiroki Haradome, and Osamu Abe. "Altered structural connectivity of pain-related brain network in burning mouth syndrome—investigation by graph analysis of probabilistic tractography." Neuroradiology 59, no. 5 (March 30, 2017): 525–32. http://dx.doi.org/10.1007/s00234-017-1830-2.

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Yu, Xin, Tao Zhang, Jin Feng Wang, Zhi Wei Li, Lin Yi, and Yu Feng Li. "Research on Correlation between Insulation Performances and Damage Degree of Burned Cable." Materials Science Forum 922 (May 2018): 180–85. http://dx.doi.org/10.4028/www.scientific.net/msf.922.180.

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In this paper, the insulation near the fault point of a breakdown 220 kV cable joint for burned cable, which kept burning for about one hour, was investigated. The relationship between insulation performance and damage degree of burned cable was analyzed by comprehensive test of material performance. Differential scanning calorimetry (DSC) test results showed that the shoulder peak temperature could reflect the heat history of the materials. There was a correlation between damage degree and the characteristic absorption peak of spectrum (IR) graph. The result of mechanical performance was different obviously. The results of broadband dielectric spectrum showed that the relative permittivity and dielectric loss factor for samples close to the fault point were smaller. By the microstructure observation of sample crystal distribution form, the above conclusions were proved. As a conclusion, DSC, IR, SEM and dielectric performance analysis results matched the real situation, showed that these methods was feasible and effective to judge the damage degree of burned cable.

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Thamattoor Raman, Krishna Mohan. "Simulation of Spread and Control of Lesions in Brain." Computational and Mathematical Methods in Medicine 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/383546.

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A simulation model for the spread and control of lesions in the brain is constructed using a planar network (graph) representation for the central nervous system (CNS). The model is inspired by the lesion structures observed in the case of multiple sclerosis (MS), a chronic disease of the CNS. The initial lesion site is at the center of a unit square and spreads outwards based on the success rate in damaging edges (axons) of the network. The damaged edges send out alarm signals which, at appropriate intensity levels, generate programmed cell death. Depending on the extent and timing of the programmed cell death, the lesion may get controlled or aggravated akin to the control of wild fires by burning of peripheral vegetation. The parameter phase space of the model shows smooth transition from uncontrolled situation to controlled situation. The simulations show that the model is capable of generating a wide variety of lesion growth and arrest scenarios.

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Al Rashdi, Shabib Sulaiman Ali, Ganesh Patil, Noura Ali Moosa Al Balushi, and A. M. Saravanan. "Biogas production potential from palm waste in Sultanate of Oman." Research Journal of Biotechnology 17, no. 12 (November 25, 2022): 159–64. http://dx.doi.org/10.25303/1712rjbt1590164.

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In Oman, palm wastes are estimated at thousands of tons per year. Imagine that this huge amount of waste can be used as an alternative to energy or as a fuel. This project shows the possibility of obtaining cellulose from waste palm trees to protect Oman from the environmental damage caused by burning these wastes. The result obtained from the first experiment was that 80g of raw material gave about 2.5 – 3g of cellulose. In the second experiment, 3.3g of raw material gave about 1.8 – 1.9g of cellulose, while in the third experiment, 4g of the same raw material of the second experiment gave about 1.5 - 1.6g of cellulose. The final products' FTIR showed the functional groups and compared them with the pure cellulose graph. The biogas was produced at the end of this project by using an anaerobic digester. The total volume of the anaerobic digester has been calculated as 7.2 m3 to do the digestion process.

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Simon, Marek, Ladislav Huraj, Iveta Dirgova Luptakova, and Jiri Pospichal. "How to Burn a Network or Spread Alarm." MENDEL 25, no. 2 (December 20, 2019): 11–18. http://dx.doi.org/10.13164/mendel.2019.2.011.

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This paper compares centrality indices usage within a heuristic method for a fast spread of alarm, or crucial information. Such indices can be used as a core part within more sophisticated optimisation methods, which should determine a graph parameter - burning number, defining, how fast can an alarm spread through all nodes. In this procedure at each time step a new chosen node is alarmed (i.e. burned) “from outside”, and already alarmed nodes at each time step then alarm their neighbours. The procedure ends, when all the nodes are alarmed (i.e. burned). The optimisation heuristic should choose such ordered sequence of nodes, which are to be alarmed “from outside”, that their number, equal the number of time steps (i.e. burning number) necessary to alarm the whole network, is minimised. The NP completeness of the problem necessitates a usage of heuristics. However, even the heuristics can be slower, reaching towards a global optimum, or faster, exchanging part of the quality for a time. This paper studies the usage of centrality indices in a simpler and faster heuristic. It should be useful e.g. for a mobile network of cars or drones, when an optimal solution cannot be computed in advance, or take too much CPU time, since the connections within the dynamic network might not exist any longer. A wide range of centrality indices was tested on selected networks, both real as well as artificially generated. While the performances of indices substantially differ for different types of networks, results show, which centrality indices work well across all tested networks.

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Chernenko, A. S., G. L. Shyngarov, M. A. Ivanov, V. V. Kalinchak, and A. K. Kopiyka. "Measuring the burnout rate of flammable liquids." Physics of Aerodisperse Systems, no. 60 (December 15, 2022): 105–19. http://dx.doi.org/10.18524/0367-1631.2022.60.267068.

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The article discusses the express method proposed by the authors for experimental measurement of the mass burnout rate of liquid combustible substances. Describes the experiments carried out with various liquids, which impregnated products made of porous heat-resistant material in the form of spheres or flat cylindrical "tablets" of different diameters. These products were placed on digital scales and set on fire. A video camera connected to a computer recorded the readings of the scales and simultaneously monitored the combustion process, fixing the value of the current time t. When processing the video file, the dependence of the mass of the liquid burning on the sample on time M = f(t) was plotted. On this graph, a linear section was allocated to measure the mass loss rate, and the specific mass burnout rate of the liquid ṁ was calculated from it. The results were compared with data obtained by other researchers in experiments using various methods for determining ṁ: in particular, with the methods of "stationary sphere", "suspended drop", burnout in a tubular burner, and also from a flat free surface.

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Mitrovic, N. S., B. S. Zlatkov, M. V. Nikolic, A. M. Maricic, O. S. Aleksic, S. R. Djukic, and H. Danninger. "Soft magnetic properties of MnZn ferrites prepared by powder injection moulding." Science of Sintering 44, no. 3 (2012): 355–64. http://dx.doi.org/10.2298/sos1203355m.

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In this study, properties of soft-magnetic manganese zinc ferrite manufactured by powder injection moulding - PIM technology were presented. A powder consisting of Mn1- xZnxFe2O4 with small addition of hematite ?-Fe2O3 was mixed with an organic binder (wax and thermoplastic) to form ferrite feedstock. The ferrite feedstock was injected in a mould with a cavity shaped like a small cylinder with a hole on the main axis. Injection moulded samples were then solvent, thermally debinded and sintered in air atmosphere. Structure of sintered sample was characterized using X-ray diffractometry, scanning electron microscopy and thermomagnetic measurements. Magnetic properties were measured by hysteresis graph at different frequencies up to 1 kHz. Sintered sample contains a mixture of two phases Mn0.6Zn0.4Fe2O4 (68 wt. %) and ?-Fe2O3 (32 wt. %). The Curie temperature is TC ? 220?C for the green sample but after the heating up to 470?C, TC increase up to about 300?C. The high increase of normalized magnetic permeability of about 800 % was observed due to melting and burning of binder. The hysteresis loop of sintered MnZn ferrite toroidal cores has an R-shape with saturation of 0.44 T and remanence ratio of 0.49. The low value of coercivity (only 47 A/m) was related to the presence of ?-Fe2O3 crystalline phase and attained already optimum density (? ? 4.8 g/cm?) i.e. observed low level of porosity. Attained relative magnetic permeability ?r ? 2000 as well as power losses Ps ? 21 W/kg for sintered sample (at 1 kHz; 0.39 T) is in agreement with the MnZn ferrite commercial samples.

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Baubek, Askar, Michael Zhumagulov, Nurlan Kartjanov, Samal Sadykova, and Muratbek Arpabekov. "Experimental test of Water-Oil Emulsion Combustion." E3S Web of Conferences 178 (2020): 01012. http://dx.doi.org/10.1051/e3sconf/202017801012.

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This report dwells on the scientific study of the vortical device. The device is designed for efficient combustion of fossil fuels. Oil-water emulsion was taken as an example of alternative fuel. Although the functionality of the burner device is not limited to this fuel only. The innovative burner device under investigation is based on principal of vortical motion of fuel air mixture. There is a precombustion chamber specially designed, where inflammation and partial combustion of the swirling flow takes place. The article describes experiment on defining the geometric dimensioning of the burner discharge nozzle in relation to a combustion chamber. The position of the outlet nozzle inside of the burner is the main input parameter of this research. The authors analyzed the influence of this parameter on the pressure inside the combustion chamber and the electric load of the fan for the supplying combustion air. The position ranged from 0 to 120%. The optimal position is at 50% of the total length of the burner chamber. The pressure graph has an extremum in this position, and the electric energy consumption by the fan changes less significantly with further deepening of the output nozzle than earlier. The Results are presented for cold (air blowing only) and hot experiment (burning). This experiment proved the need for the design of the inner part of the discharge nozzle, which is a design feature of the burner device for which the European patent was obtained. The patent link is presented in the list of references.

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Mitsche, Dieter, Paweł Prałat, and Elham Roshanbin. "Burning Graphs: A Probabilistic Perspective." Graphs and Combinatorics 33, no. 2 (February 6, 2017): 449–71. http://dx.doi.org/10.1007/s00373-017-1768-5.

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Liu, Huiqing, Ruiting Zhang, and Xiaolan Hu. "Burning number of theta graphs." Applied Mathematics and Computation 361 (November 2019): 246–57. http://dx.doi.org/10.1016/j.amc.2019.05.031.

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Garcia-Diaz, Jesus, Julio Cesar Perez-Sansalvador, Lil Maria Xibai Rodriguez-Henriquez, and Jose Alejandro Cornejo-Acosta. "Burning Graphs Through Farthest-First Traversal." IEEE Access 10 (2022): 30395–404. http://dx.doi.org/10.1109/access.2022.3159695.

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Zhang, Ruiting, Yingying Yu, and Huiqing Liu. "Burning Numbers of t-unicyclic Graphs." Bulletin of the Malaysian Mathematical Sciences Society 45, no. 1 (October 4, 2021): 417–30. http://dx.doi.org/10.1007/s40840-021-01194-9.

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Zhang, Ruiting, Yingying Yu, and Huiqing Liu. "Burning Numbers of t-unicyclic Graphs." Bulletin of the Malaysian Mathematical Sciences Society 45, no. 1 (October 4, 2021): 417–30. http://dx.doi.org/10.1007/s40840-021-01194-9.

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Li, Yinkui, Xiaoxiao Qin, and Wen Li. "The generalized burning number of graphs." Applied Mathematics and Computation 411 (December 2021): 126306. http://dx.doi.org/10.1016/j.amc.2021.126306.

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Zhang, Ruiting, Yingying Yu, and Huiqing Liu. "Correction to: Burning Numbers of t-unicyclic Graphs." Bulletin of the Malaysian Mathematical Sciences Society 45, no. 2 (January 10, 2022): 953. http://dx.doi.org/10.1007/s40840-021-01238-0.

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Sim, Kai An, Ta Sheng Tan, and Kok Bin Wong. "On the Burning Number of Generalized Petersen Graphs." Bulletin of the Malaysian Mathematical Sciences Society 41, no. 3 (November 30, 2017): 1657–70. http://dx.doi.org/10.1007/s40840-017-0585-6.

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Saha, Manabendra, Giovanni Gitto, and Bassam B. Dally. "Burning characteristics of grape marc under mild combustion conditions." Experimental Thermal and Fluid Science 114 (June 2020): 110059. http://dx.doi.org/10.1016/j.expthermflusci.2020.110059.

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Yagodka, Evgeniy Alekseevich, and Aleksey Aleksandrovih Zhabin. "Support for management decision-making based on express fire modeling technologies based on a field model." Technology of technosphere safety 95 (2022): 102–20. http://dx.doi.org/10.25257/tts.2022.1.95.102-120.

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Introduction. In order to improve the well-being of citizens and economic growth of the state in the Russian Federation reform of control and Supervisory activity, which is based on the introduction of a risk-based approach when planning inspections, developing and applying safety requirements, including fire safety. To implement a risk-based approach, it is necessary to take into account the degree of risk of harm to legally protected values, which requires an assessment of fire risks based on deterministic methods (techniques). However, the complexity of these methods does not allow them to be applied in an operational mode without special software and highly qualified specialists, which makes it difficult to implement a risk-based approach and may lead to making unjustified management decisions. Goals and objectives. To support management decision-making when implementing a risk-based approach, it is necessary to develop an information equivalent of basic (full, detailed) versions of fire risk assessment methods that meet the conditions of brevity, simplicity and accessibility to a wide range of specialists, while ensuring high accuracy of calculation results. Method of research. To obtain the results, we used general scientific and special methods of scientific knowledge – system, regression, retrospective and comparative analysis, synthesis, generalization, graph theory, and numerical experiment. Research result. Rapid fire risk assessment formulas have been developed that allow determining the required evacuation time when the critical values of three fire hazards are reached: loss of visibility, elevated temperature and HCl, when two types of solid fire loadings are burning in rooms with an area of 1000 to 10000 m2 and a height of 10 to 20 m. Express formulas are developed on the basis of a field mathematical model of fire, the relative error of calculations based on Express formulas is no more than 8 %. Conclusion. The use of Express formulas as a support for management decision-making will allow officials of GPN bodies in the shortest possible time (up to 5 minutes) and with high reliability (accuracy) make informed decisions about the presence (absence) of violations of mandatory fire safety requirements that pose a threat to the life and health of people, and the need to apply administrative measures, which will exclude cases of insufficient measures taken by the audited persons to ensure the safety of citizens, as well as unjustified restrictions on the right to risk their own property. Keywords: rapid assessment, fire risk, risk-based model, fire hazards, state fire supervision.

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Janssen, Remie. "The Burning Number of Directed Graphs: Bounds and Computational Complexity." Theory and Applications of Graphs 7, no. 1 (2020): 1–14. http://dx.doi.org/10.20429/tag.2020.070108.

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Lysenko, O. M., H. M. Veremiichuk, and O. A. Siryi. "RESEARCH OF BURNING OF AGRICULTURAL PELLETS IN BOILERS WITH CAPACITY UP TO 25 kW." Thermophysics and Thermal Power Engineering 46, no. 3 (August 17, 2022): 99–108. http://dx.doi.org/10.31472/ttpe.3.2022.10.

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The main purpose of this research is to determine the main dependence’s of the agricultural pellets combustion process and to study the influence of regime parameters on the distribution of temperatures in the combustion chamber, as well as to analyze the biofuels productivity characteristics. Research methods: experimental and theoretical. Results. The research of biofuel combustion process was carried out at the experimental facility of solid fuel boiler with a pellet burner for a passive type house heating. During experimental researches samples of wood pellets, rapeseed pellets and beets pulp were used. On the received graphs the changes in the temperature state of the combustion chamber at the stage of pelletʼs ignition, burning and fading were reflected. It was found that the largest increase in temperature occurs near the wall of the boiler, which is opposite to the burner. As can be seen on the graphs, temperature fluctuations occur as a result of the periodic burning of biofuel in the burner and the arrival of a new portion of pellet from the hopper. As the experiments showed, the temperature level at burning of rapeseed pellets is much lower than in comparison with wood pellets, and to go to the established mode of burning of beet pulp pellets is generally problematic. It is obvious that when setting up the fuel supply system and modes of operation of the fuel it is necessary to take into account heat physical characteristics of fuel, first of all moisture and heat capacity, as well as yield of volatile combustible components. For this purpose, a gas analysis was carried out when burning wood pellets. The selection of combustion products was done in the wild immediately after the boiler. As a result, the NOx and CO concentrations of the appropriate temperature were obtained at the sample site. The nitrogen oxide concentrations should be considered moderate, which cannot be argued about the concentration of carbon monoxide, which requires further research. The obtained results can be used to increase the efficiency of combustion process at burning biofuel in boilers of low power communal and industrial heat power, social-budget sphere and individual-household sector.

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Ahmed, Wasim, Josep Vidal-Alaball, Joseph Downing, and Francesc López Seguí. "COVID-19 and the 5G Conspiracy Theory: Social Network Analysis of Twitter Data." Journal of Medical Internet Research 22, no. 5 (May 6, 2020): e19458. http://dx.doi.org/10.2196/19458.

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Background Since the beginning of December 2019, the coronavirus disease (COVID-19) has spread rapidly around the world, which has led to increased discussions across online platforms. These conversations have also included various conspiracies shared by social media users. Amongst them, a popular theory has linked 5G to the spread of COVID-19, leading to misinformation and the burning of 5G towers in the United Kingdom. The understanding of the drivers of fake news and quick policies oriented to isolate and rebate misinformation are keys to combating it. Objective The aim of this study is to develop an understanding of the drivers of the 5G COVID-19 conspiracy theory and strategies to deal with such misinformation. Methods This paper performs a social network analysis and content analysis of Twitter data from a 7-day period (Friday, March 27, 2020, to Saturday, April 4, 2020) in which the #5GCoronavirus hashtag was trending on Twitter in the United Kingdom. Influential users were analyzed through social network graph clusters. The size of the nodes were ranked by their betweenness centrality score, and the graph’s vertices were grouped by cluster using the Clauset-Newman-Moore algorithm. The topics and web sources used were also examined. Results Social network analysis identified that the two largest network structures consisted of an isolates group and a broadcast group. The analysis also revealed that there was a lack of an authority figure who was actively combating such misinformation. Content analysis revealed that, of 233 sample tweets, 34.8% (n=81) contained views that 5G and COVID-19 were linked, 32.2% (n=75) denounced the conspiracy theory, and 33.0% (n=77) were general tweets not expressing any personal views or opinions. Thus, 65.2% (n=152) of tweets derived from nonconspiracy theory supporters, which suggests that, although the topic attracted high volume, only a handful of users genuinely believed the conspiracy. This paper also shows that fake news websites were the most popular web source shared by users; although, YouTube videos were also shared. The study also identified an account whose sole aim was to spread the conspiracy theory on Twitter. Conclusions The combination of quick and targeted interventions oriented to delegitimize the sources of fake information is key to reducing their impact. Those users voicing their views against the conspiracy theory, link baiting, or sharing humorous tweets inadvertently raised the profile of the topic, suggesting that policymakers should insist in the efforts of isolating opinions that are based on fake news. Many social media platforms provide users with the ability to report inappropriate content, which should be used. This study is the first to analyze the 5G conspiracy theory in the context of COVID-19 on Twitter offering practical guidance to health authorities in how, in the context of a pandemic, rumors may be combated in the future.

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Wilkinson, Kerry, Renata Ristic, Imogen McNamara, Beth Loveys, WenWen Jiang, and Mark Krstic. "Evaluating the Potential for Smoke from Stubble Burning to Taint Grapes and Wine." Molecules 26, no. 24 (December 13, 2021): 7540. http://dx.doi.org/10.3390/molecules26247540.

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It has been well established that bushfire/wildfire smoke can taint grapes (and therefore wine), depending on the timing and duration of exposure, but the risk of smoke contamination from stubble burning (a practice employed by some grain growers to prepare farmland for sowing) has not yet been established. This study exposed excised bunches of grapes to smoke from combustion of barley straw and pea stubble windrows to investigate the potential for stubble burning to elicit smoke taint. Increased levels of volatile phenols (i.e., chemical markers of smoke taint) were detected in grapes exposed to barley straw smoke (relative to control grapes), with smoke density and the duration of smoke exposure influencing grape volatile phenols. However, the sensory panel did not perceive wine made from grapes exposed to low-density smoke to be tainted, despite the presence of low levels of syringol providing compositional evidence of smoke exposure. During the pea stubble burn, grapes positioned amongst the burning windrows or on the edge of the pea paddock were exposed to smoke for ~15–20 and 30–45 min, respectively, but this only resulted in 1 µg/kg differences in the cresol and/or syringol concentrations of smoke-affected grapes (and 1 µg/L differences for wine), relative to controls. A small, but significant increase in the intensity of smoke aroma and burnt rubber flavor of wine made from the grapes positioned amongst the burning pea stubble windrows provided the only sensory evidence of any smoke taint. As such, had vineyards been located immediately downwind from the pea stubble burn, it is unlikely that there would have been any smoke contamination of unharvested grapes.

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Kerimova, Z. K., and K. Y. Alieva. "Production of emulsion crème from the Izabella grape seeds and the study of its pharmacocosmetological properties." Reviews on Clinical Pharmacology and Drug Therapy 10, no. 3 (September 15, 2012): 50–52. http://dx.doi.org/10.17816/rcf10350-52.

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Using the method of polyfraction extraction, the oil, spiritus and water extractions from the Izabella grape seeds were received by means of hexane taking out, the emulsion crème of the water/oil type on that base was developed. The treatment effect of emulsion crème on the thermic and chemical burnings was determined in the experiment. During the primary cosmetology trial the emulsion crème was effective for removal and prevention of wrincklies.

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De Silva, S. J., Udara S. P. R. Arachchige, and A. H. L. R. Nilmini. "Comparative Study of Bioethanol Production from Waste Banana Fruits and Grape Fruits." Asian Journal of Chemistry 34, no. 9 (2022): 2253–56. http://dx.doi.org/10.14233/ajchem.2022.23770.

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Petroleum consumption in the transportation sector causes severe damage to the environment. Bioethanol is used as a biofuel or fuel additive because of its properties that give clean burning, reducing air pollution and avoiding global warming. Still, Sri Lanka depends on petroleum fuel. As a result, Sri Lanka generates 270000 tons of fruit waste per year, including bananas, and it is time to investigate alternatives to fossil fuel. It would diminish environmental pollution and reduce the dependence on imported fossil fuels. In present study, the waste of bananas and grapes is used to produce bioethanol using S. cerevisiae (Baker’s yeast). Temperatures of 30 ºC and pH 5.0 were maintained in the fermentation medium. This study shows that waste grapes have a higher ethanol concentration, 6.08% greater than bananas at 5.11%. The grape and banana ethanol yields are 46.77 g/L and 39.46 g/L, and the specific gravity shows 0.871 and 0.882, respectively.

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Svobodová, Nicole, Martin Benýšek, and Radek Štefan. "Analysis of Zone Fire Models and their Application in Structural Fire Design." Solid State Phenomena 322 (August 9, 2021): 127–35. http://dx.doi.org/10.4028/www.scientific.net/ssp.322.127.

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This paper is focused on a comparison of zone fire modelling software tools and their application in structural fire design. The analysis of the zone models is performed for five selected computer programs, namely Argos, Branzfire, B-RISK, CFAST, and OZone. The limits and input parameters ofthe zone fire modelling software tools are described. In each software, two variants of the analysed compartment are created for simulating two types of fire scenario, including the fuel-controlled fire and the ventilation-controlled fire. The burning regimes are defined based on two heat release rate(HRR) curves, determined according to EN 1991-1-2. The HRR curves parameters are used as the main input data into the fire modelling software. The fire simulation method in each fire modelling software is selected based on the software capabilities. Although each program requires a different amount of input parameters, the aim was to create the same model in all programs and to compare the results. The fire modelling software outputs are exported into a spreadsheet. Subsequently, a comparison of the resulting graphs is performed, particularly the heat release rate graphs and the upper layertemperature evolution graphs. The fire resistance assessment of a simply-supported concrete slab panel is performed for all zone fire models and then the results are compared. The fire modelling software tools are finally quantitatively and qualitatively evaluated and compared to assess their differences.

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Frišták, Vladimír, Eduardo Moreno-Jimenéz, Teresa Fresno, and Elena Diaz. "Effect of Physical and Chemical Activation on Arsenic Sorption Separation by Grape Seeds-Derived Biochar." Separations 5, no. 4 (December 19, 2018): 59. http://dx.doi.org/10.3390/separations5040059.

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The utilization of carbon-rich pyrolysis materials in the separation processes of metalloids plays a crucial role in analytes pre-concentration techniques and opens a burning issue in new sorbents development. This study characterized the effect of physical and chemical activation with subsequent iron impregnation of grape seed-derived biochar on sorption removal of As from model aqueous solutions. Sorbents that were produced in slow pyrolysis process at 600 °C were characterized by SEM, elemental, and specific surface area analysis. Sorption separation of As by the studied materials was characterized as on contact time and an initial concentration dependent process reaching sorption equilibrium in 1440 min. Air activated biochar (A1GSBC) showed about 7.7 times and HNO3 activated biochar (A2GSBC) about 6.8 times higher values of Qmax as compared to control (GSBC). A1GSBC and A2GSBC can be easily and effectively regenerated by alkali agent in several cycles. All of these results showed the practical use of the activation process to produce effective sorption materials with increased surface area and improved sorption potential for anionic forms separation from liquid wastes.

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Ferreira de Gouveia, José Rafael, Cristina Rodrigues Nascimento, José Galdino De Oliveira Júnior, Geber Barbosa De Albuquerque Moura, and Pabrício Marcos Oliveira Lopes. "Correlação entre Área Plantada x Queima da cana-de-açúcar no Litoral e Zona da Mata de Pernambuco." Revista Brasileira de Geografia Física 15, no. 2 (April 21, 2022): 841. http://dx.doi.org/10.26848/rbgf.v15.2.p841-855.

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Servindo como matéria-prima para a produção de biomassa e biocombustíveis, a cana-de-açúcar se apresenta como uma cultura vastamente utilizada. No estado de Pernambuco, sua produção ocorre nas mesorregiões Metropolitana do Recife e Mata Pernambucana. O estado apresenta relevo acidentado, o que dificulta a utilização de máquinas colheitadeiras, neste sentido, a colheita é realizada de forma manual com a queima para despalha e posterior corte. Esta prática implica em diversos prejuízos para a fauna e flora local, além de contribuir com o efeito estufa. Este artigo tem como objetivo avaliar a correlação entre área plantada e a queima da cana-de-açúcar nas mesorregiões citadas, através de dados obtidos de imagens de satélites. Para tanto, foram utilizadas imagens do sensor MODIS a bordo das plataformas combinadas TERRA e AQUA a fim de identificar as áreas afetadas pela queima. Os mapas disponibilizados pelo Mapbiomas foram empregados para a caracterização da cobertura vegetal das áreas analisadas. Para caracterizar a prática da queima e a resposta da vegetação, foram utilizados os gráficos do Índice de Vegetação da Diferença Normalizada (NDVI) disponibilizados pelo SATVeg. Os dados demonstram que o coeficiente de correlação entre o NDVI e a ocorrência dos focos de calor é fraco. Apesar disto, os valores mais baixos do índice NDVI coincidem com o período de queima, o que evidencia a utilização desta prática para a realização da colheita da cana-de-açúcar. Desta maneira, as técnicas de sensoriamento remoto possibilitaram a identificação de áreas de produção de cana-de-açúcar com base nas áreas afetadas pela queima.Palavras-Chave: NDVI, imagens de satélite, focos de calor, cobertura vegetal. Correlation between Planted Area x Sugar Cane Burning on the Coast and Zona da Mata of Pernambuco A B S T R A C TServing as a raw material for the production of biomass and biofuels, sugarcane presents itself as a widely used crop. In the state of Pernambuco, its production takes place in the Metropolitana do Recife and Mata Pernambucana mesoregions. The state has a rugged terrain, which makes it difficult to use harvesting machines, in this sense, the harvest is carried out manually with burning for husk and subsequent cutting. This practice entails several damages to the local fauna and flora, in addition to contributing to the greenhouse effect. This article aims to evaluate the correlation between planted area and sugarcane burning in the aforementioned mesoregions, using data obtained from satellite images. For this purpose, MODIS sensor images aboard the combined TERRA and AQUA platforms were used in order to identify the areas affected by the burning. The maps provided by Mapbiomas were used to characterize the vegetation cover of the analyzed areas. To characterize the practice of burning and the response of vegetation, the Normalized Difference Vegetation Index (NDVI) graphs provided by SATVeg were used. The data demonstrate that the correlation coefficient between the NDVI and the occurrence of hot spots is weak. Despite this, the lowest values of the NDVI index coincide with the burning period, which shows the use of this practice to carry out the sugarcane harvest. In this way, remote sensing techniques enabled the identification of sugarcane production areas based on the areas affected by the burning.Keywords: NDVI, satellite images, hot spots, vegetation cover.

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Cheng, Xi, Jianming Wu, Yulin Li, Chenguang Yao, and Guisheng Yang. "SEBS-based thermoplastic elastomers containing aluminum hypophosphite and melamine cyanurate: Thermal degradation, flame retardancy, and mechanical properties." Journal of Fire Sciences 37, no. 2 (March 2019): 137–54. http://dx.doi.org/10.1177/0734904119830591.

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Aluminum hypophosphite combined with melamine cyanurate and poly(phenylene oxide) was applied to flame-retard TPE-S system (blends of SEBS and polyolefin). The flame-retardant properties of the TPE-S/AHP/MCA/PPO were investigated by LOI and vertical burning test (UL-94). The results indicated that TPE-S containing 16 wt% AHP, 20 wt% MCA, and 10 wt% PPO reached a V-0 rating in the UL-94 test, and its LOI value was 28.2%. It performed well in the cone calorimeter (reduction in peak heat release rate from 2001 to 494 kW m−2). Thermogravimetric-Fourier transform infrared spectroscopy tests showed that AHP and MCA acted in gaseous phase, while AHP and PPO helped to form char residue. The SEM graphs demonstrated that continuous and compact films cover bubbles of the char layer in TPE-S/AHP/MCA/PPO. The proposed flame-retardant mechanisms of such systems were summarized.

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Kenan, Çeven, Günaydin Karakan, and Nejla Çeven. "Impact of weft yarn type and fabric weft density on burning behavior, tearing strength and air permeability for different types of antibacterial drapery fabrics." Tekstilna industrija 69, no. 1 (2021): 4–16. http://dx.doi.org/10.5937/tekstind2101004k.

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Drapery fabrics are textile products utilized for home and decorative textiles. Recently there have been new functional requirements for the drapery fabrics such as flame retardancy, antimicrobial efficiency, UV protection, etc. This study has been conducted to investigate the effect of weft yarn type and weft density on drapery fabrics' burning behaviour, tearing strength and air permeability properties. "A special inherently flame-retardant yarn" was used as the warp and weft yarns of the woven drapery fabrics while "a special inherently and antibacterial yarn" was also used as the weft yarn in some of the sample groups. Two main fabric groups each consisting of 12 woven drapery samples with different weft yarns and weft densities were separately evaluated among themselves by using SPSS Statistical software package and bar graphs. Burning behaviours of the samples in terms of damage length and damage width with the ignition source were satisfying both for the drapery samples with the special inherently flame-retardant weft yarn as well as those with the special inherently flame retardant and antibacterial yarn weft yarns. In other words, usage of inherently flame retardant and antibacterial yarn as the weft yarns did not contribute negatively on the flame retardancy of drapery fabrics. The results of two-way ANOVA test indicated that weft yarn type was a significant factor for tearing strength in warp and weft wise while weft density and the interaction of weft yarn type and weft density factors were non-significant factors on tear strength values in warp and weft wises at significance level of 0.05. Additionally, correlation analyses revealed that weft yarn tenacity values were highly correlated with the drapery fabrics' weft tearing strength values. Moreover, weft yarn type, weft density and their interaction were influential factors on air permeability of the drapery fabrics at significance level of 0.05.

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Florindo, Tiago, Ana I. Ferraz, Ana C. Rodrigues, and Leonel J. R. Nunes. "Residual Biomass Recovery in the Wine Sector: Creation of Value Chains for Vine Pruning." Agriculture 12, no. 5 (May 7, 2022): 670. http://dx.doi.org/10.3390/agriculture12050670.

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Waste management is a current and transversal problem in all production areas, including agriculture. Within this economic activity, wine production generates a large amount of waste, namely, that resulting from the winemaking activity itself, such as pomace and grape stalks, and waste resulting from the management of the vineyards, with operations such as vine pruning. The management of vine pruning residuals has traditionally been conducted by burning leftovers on-site, without any use for the energy produced. This research analyzed the potential for the valorization of residual biomass resulting from vine pruning by creating a business model based on value chains of local scale. For this analysis, several samples of residues resulting from the “Loureiro” vine variety planted in Ponte de Lima (northern Portugal) were collected and characterized. The objective of the small-scale business model created, in addition, to solving the environmental problems related to the disposal of waste from agricultural activities, a value chain can be established, contributing to increasing the income of the farmers while introducing a circular bioeconomy and sustainable rural development practices.

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Lyubov, V. K., D. G. Chukhchin, and A. N. Popov. "Thermal Engineering Tests of Heating Boiler Houses when Working on Peat Fuel." ENERGETIKA. Proceedings of CIS higher education institutions and power engineering associations 65, no. 5 (October 4, 2022): 422–35. http://dx.doi.org/10.21122/1029-7448-2023-65-5-422-435.

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Modern development of society and the economy is generally accompanied by abandonment of non-renewable fuels in the system of existing attitudes toward environmental issues and resource conservation. The paper presents the results of complex operational tests of КВм-2.0 water boilers with automatic stoker and КВр-0.4K at heat supply facilities of the Arkhangelsk region under the typical operating conditions on coal, fuel mixtures, and also peat briquettes and sod peat. Experimental work was carried out using modern methods and advanced technical means. Within the framework of the research on the conversion of boilers to peat fuel, balance experiments were carried out; technical, economic and environmental performance indicators were obtained; the selection and analysis of focal residues were carried out, fine solid and soot particles polluted into the environment were studied in detail. The paper presents graphs of changes in gross efficiency, heat loss with exhaust gas, heat loss with incomplete combustion, and concentrations of sulfur and nitrogen oxides during the cycle between loading peat briquettes into the КВр-0.4K boiler, as well as graphs of changes in the heat balance components and gross efficiency all boiler units under investigation. The conversion of heat generating plants to peat fuel combustion makes it possible to achieve a significant reduction in emissions of solid and soot particles without upgrading ash-collecting plants. Complex experimental studies conducted of existing hot water boilers with a nominal heating capacity of 0.4 and 2.0 MW have shown the possibility, as well as the energy-environmental efficiency of burning briquetted and sod peat in the combustion chambers of these heat generating plants.

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Summerson, Vasiliki, Claudia Gonzalez Viejo, Alexis Pang, Damir D. Torrico, and Sigfredo Fuentes. "Review of the Effects of Grapevine Smoke Exposure and Technologies to Assess Smoke Contamination and Taint in Grapes and Wine." Beverages 7, no. 1 (January 25, 2021): 7. http://dx.doi.org/10.3390/beverages7010007.

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Grapevine smoke exposure and the subsequent development of smoke taint in wine has resulted in significant financial losses for grape growers and winemakers throughout the world. Smoke taint is characterized by objectional smoky aromas such as “ashy”, “burning rubber”, and “smoked meats”, resulting in wine that is unpalatable and hence unprofitable. Unfortunately, current climate change models predict a broadening of the window in which bushfires may occur and a rise in bushfire occurrences and severity in major wine growing regions such as Australia, Mediterranean Europe, North and South America, and South Africa. As such, grapevine smoke exposure and smoke taint in wine are increasing problems for growers and winemakers worldwide. Current recommendations for growers concerned that their grapevines have been exposed to smoke are to conduct pre-harvest mini-ferments for sensory assessment and send samples to a commercial laboratory to quantify levels of smoke-derived volatiles in the wine. Significant novel research is being conducted using spectroscopic techniques coupled with machine learning modeling to assess grapevine smoke contamination and taint in grapes and wine, offering growers and winemakers additional tools to monitor grapevine smoke exposure and taint rapidly and non-destructively in grapes and wine.

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Rice, I. G. "Split Stream Boilers for High-Temperature/High-Pressure Topping Steam Turbine Combined Cycles." Journal of Engineering for Gas Turbines and Power 119, no. 2 (April 1, 1997): 385–94. http://dx.doi.org/10.1115/1.2815586.

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Research and development work on high-temperature and high-pressure (up to 1500°F TIT and 4500 psia) topping steam turbines and associated steam generators for steam power plants as well as combined cycle plants is being carried forward by DOE, EPRI, and independent companies. Aeroderivative gas turbines and heavy-duty gas turbines both will require exhaust gas supplementary firing to achieve high throttle temperatures. This paper presents an analysis and examples of a split stream boiler arrangement for high-temperature and high-pressure topping steam turbine combined cycles. A portion of the gas turbine exhaust flow is run in parallel with a conventional heat recovery steam generator (HRSG). This side stream is supplementary fired opposed to the current practice of full exhaust flow firing. Chemical fuel gas recuperation can be incorporated in the side stream as an option. A significant combined cycle efficiency gain of 2 to 4 percentage points can be realized using this split stream approach. Calculations and graphs show how the DOE goal of 60 percent combined cycle efficiency burning natural gas fuel can be exceeded. The boiler concept is equally applicable to the integrated coal gas fuel combined cycle (IGCC).

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Journal articles on the topic 'Graph burning'

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