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Billi, M., Mascareno, A., Henriquez, P. A., Rodriguez, I., Padilla, F., & Ruz, G. A. (2022). Learning from crises? The long and winding road of the salmon industry in Chiloe Island, Chile. Mar. Pol., 140, 105069.
Abstract: The rapid development of salmon aquaculture worldwide and the growing criticism of the activity in recent decades have raised doubts about the capacity of the sector to learn from its own crises. In this article, we assess the discursive, behavioral and outcome performance dimensions of the industry to identify actual learning and lessons to be learned. We focus on the case of Chiloe Island, Chile, a global center of salmon production since 1990 that has gone through two severe crises in the last 15 years (2007-2009 ISAV crisis and 2016 red tide crisis). On the basis of a multi-method approach combining qualitative analysis of interviews and statistical data analysis, we observe that the industry has discursively learned the relevance of both self-regulation and the wellbeing of communities. However, at the behavioral and outcome performance levels, the data show a highly heterogeneous conduct that questions the ability of the sector as a whole to learn from crises. We conclude that detrimental effects for ecosystems and society will increase if learning remains at the level of discourses. Without significant changes in operational practices and market performance there are no real perspectives for the sustainability of the industry. This intensifies when considering the uneven responses to governance mechanisms. The sector needs to adapt its factual performance to sustainable goals and reflexively monitor this process. The first step for achieving this is to produce reliable data to make evidence-based decisions that align the operational dynamics of the entire sector with a more sustainable trajectory in the near future, as well as advancing towards hybrid and more reflexive governance arrangements.
Keywords: Crisis; Learning; Discourse; Behavior; Outcome performance; Aquaculture; Salmon industry; Governance; Regulation
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Caceres, G., Nasirov, S., Zhang, H. L., & Araya-Letelier, G. (2015). Residential Solar PV Planning in Santiago, Chile: Incorporating the PM10 Parameter. Sustainability, 7(1), 422–440.
Abstract: This paper addresses an economic study of the installation of photovoltaic (PV) solar panels for residential power generation in Santiago, Chile, based on the different parameters of a PV system, such as efficiency. As a performance indicator, the Levelized Cost of Energy (LCOE) was used, which indicates the benefit of the facility vs. the current cost of electrical energy. In addition, due to a high level of airborne dusts typically associated with PM10, the effect of the dust deposition on PV panels' surfaces and the effect on panel performance are examined. Two different scenarios are analyzed: on-grid PV plants and off-grid PV plants.
Keywords: PV solar panels; efficiency; LCOE; dust; PM10; Santiago; Chile
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Cardenas, C., Guzman, F., Carmona, M., Munoz, C., Nilo, L., Labra, A., et al. (2020). Synthetic Peptides as a Promising Alternative to Control Viral Infections in Atlantic Salmon. Pathogens, 9(8), 600.
Abstract: Viral infections in salmonids represent an ongoing challenge for the aquaculture industry. Two RNA viruses, the infectious pancreatic necrosis virus (IPNV) and the infectious salmon anemia virus (ISAV), have become a latent risk without healing therapies available for either. In this context, antiviral peptides emerge as effective and relatively safe therapeutic molecules. Based on in silico analysis of VP2 protein from IPNV and the RNA-dependent RNA polymerase from ISAV, a set of peptides was designed and were chemically synthesized to block selected key events in their corresponding infectivity processes. The peptides were tested in fish cell lines in vitro, and four were selected for decreasing the viral load: peptide GIM182 for IPNV, and peptides GIM535, GIM538 and GIM539 for ISAV. In vivo tests with the IPNV GIM 182 peptide were carried out using Salmo salar fish, showing a significant decrease of viral load, and proving the safety of the peptide for fish. The results indicate that the use of peptides as antiviral agents in disease control might be a viable alternative to explore in aquaculture.`
Keywords: interfering peptides; viral treatment; RNA fish virusesViral infections in salmonids represent an ongoing challenge for the aquaculture industry. Two RNA viruses, the infectious pancreatic necrosis virus (IPNV) and the infectious salmon anemia virus (ISAV), have become a latent risk without healing therapies available for either. In this context, antiviral peptides emerge as effective and relatively safe therapeutic molecules. Based on in silico analysis of VP2 protein from IPNV and the RNA-dependent RNA polymerase from ISAV, a set of peptides was designed and were chemically synthesized to block selected key events in their corresponding infectivity processes. The peptides were tested in fish cell lines in vitro, and four were selected for decreasing the viral load: peptide GIM182 for IPNV, and peptides GIM535, GIM538 and GIM539 for ISAV. In vivo tests with the IPNV GIM 182 peptide were carried out using Salmo salar fish, showing a significant decrease of viral load, and proving the safety of the peptide for fish. The results indicate that the use of peptides as antiviral agents in disease control might be a viable alternative to explore in aquaculture.
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Carrasco, M., Alvarez, F., Velazquez, R., Concha, J., & Perez-Cotapos, F. (2019). Brush-Holder Integrated Load Sensor Prototype for SAG Grinding Mill Motor. Electronics, 8(11), 14 pp.
Abstract: One of the most widely used electro-mechanical systems in large-scale mining is the electric motor. This device is employed in practically every phase of production. For this reason, it needs to be inspected regularly to maintain maximum operability, thus avoiding unplanned stoppages. In order to identify potential faults, regular check-ups are performed to measure the internal parameters of the components, especially the brushes and brush-holders. Both components must be properly aligned and calibrated to avoid electric arcs to the internal insulation of the motor. Although there is an increasing effort to improve inspection tasks, most inspection procedures are manual, leading to unnecessary costs in inspection time, errors in data entry, and, in extreme cases, measurement errors. This research presents the design, development, and assessment of an integrated measurement prototype for measuring spring tension and other key parameters in brush-holders used in electric motors. It aims to provide the mining industry with a new, fully automatic inspection system that will facilitate maintenance and checking. Our development research was carried out specifically on the brush system of a SAG grinding mill motor. These machines commonly use SIEMENS motors; however, the instrument can be easily adapted to any motor by simply changing the physical dimensions of the prototype.
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Concha-Riedel, J., Antico, F.C., Araya-Letelier, G. (2020). Mechanical and damage similarities of adobe blocks reinforced with natural and industrial fibres. Materia, 25(4), 11pp.
Abstract: Adobe is an earthen-based material that consists of the use of a clayey soil and, most of the times, straw fibres to manufacture blocks that are afterwards sundried. This study reviews the use of three types of fibres:
vegetal, industrial and animal, for the manufacture of adobe blocks. Overall, all the fibres increase at least one order of magnitude the impact strength of plain adobe blocks and reduced the shrinkage cracking of adobe plasters in at least 50% with respect to plain adobe. Compressive and flexural strength average values were not increased nor decreased by the addition of fibres. The intrinsic variability of the mechanical properties of plain adobe persists with any of the fibres tested in this study. Based on the findings of this study, we recommend using jute fibres with a dosage of 0.5% and a length of 30 mm. |
Crutchik, D., Morales, N., Vazquez-Padin, J. R., & Garrido, J. M. (2017). Enhancement of struvite pellets crystallization in a fullscale plant using an industrial grade magnesium product. Water Sci. Technol., 75(3), 609–618.
Abstract: A full-scale struvite crystallization system was operated for the treatment of the centrate obtained from the sludge anaerobic digester in a municipal wastewater treatment plant. Additionally, the feasibility of an industrial grade Mg(OH) (2) as a cheap magnesium and alkali source was also investigated. The struvite crystallization plant was operated for two different periods: period I, in which an influent with low phosphate concentration (34.0 mg P . L (-1)) was fed to the crystallization plant; and period II, in which an influent with higher phosphate concentration (68.0 mg P . L (-1)) was used. A high efficiency of phosphorus recovery by struvite crystallization was obtained, even when the effluent treated had a high level of alkalinity. Phosphorus recovery percentage was around 77%, with a phosphate concentration in the effluent between 10.0 and 30.0 mg P .L- 1. The experiments gained struvite pellets of 0.5- 5.0 mm size. Moreover, the consumption of Mg(OH) (2) was estimated at 1.5 mol Mg added . mol P recovered (-1). Thus, industrial grade Mg(OH) (2) can be an economical alternative as magnesium and alkali sources for struvite crystallization at industrial scale.
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Crutchik, D., Rodrigues, S., Ruddle, D., & Garrido, J. M. (2018). Evaluation of a low-cost magnesium product for phosphorus recovery by struvite crystallization. J. Chem. Technol. Biotechnol., 93(4), 1012–1021.
Abstract: BACKGROUND: The development of a cost-effective process of struvite crystallization requires the selection of appropriate sources of alkali and magnesium. In this study, the effectiveness of two industrial grade products, MgO and Mg(OH)(2), as magnesium and alkali sources to recover phosphorus as struvite were investigated and compared in a first set of experiments. Subsequently, the use of industrial Mg(OH)(2) was compared in two different struvite crystallization systems, an upflow fluidized bed reactor (FBR) and a continuous stirred tank reactor (CSTR) coupled to a settler tank. RESULTS: At the same operational conditions, the consumption of MgO was higher than Mg(OH)(2) consumption. Moreover, industrial Mg(OH)(2) consumption for FBR and the CSTR operation was 1.6 and 1.1 1 mol Mg added mol(-1) P precipitated, respectively. This difference was caused by the high mixing intensity and the higher contact time between the Mg(OH)(2) slurry and the influent in the CSTR, favouring the conversion. CONCLUSIONS: Both industrial grade magnesium products are promising options for struvite crystallization. However, Mg(OH)(2) was more effective than the starting material, MgO, to recover phosphorus. Struvite crystallization by adding an industrial grade Mg(OH)(2) could be economically viable with regard to alternative physico-chemical P removal processes using metal salts, increasing the attractiveness of this P recovery process. (C) 2017 Society of Chemical Industry.
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Giustinianovich, E. A., Campos, J. L., Roeckel, M. D., Estrada, A. J., Mosquera-Corral, A., & del Rio, A. V. (2018). Influence of biomass acclimation on the performance of a partial nitritation-anammox reactor treating industrial saline effluents. Chemosphere, 194, 131–138.
Abstract: The performance of the partial nitritation/anammox processes was evaluated for the treatment of fish canning effluents. A sequencing batch reactor (SBR) was fed with industrial wastewater, with variable salt and total ammonium nitrogen (TAN) concentrations in the range of 1.75-18.00 g-NaCl L-1 and 112 – 267 mg-TAN L-1. The SBR operation was divided into two experiments: (A) progressive increase of salt concentrations from 1.75 to 1833 g-NaCl L-1; (B) direct application of high salt concentration (18 g-NaCl L-1). The progressive increase of NaCl concentration provoked the inhibition of the anammox biomass by up to 94% when 18 g-NaCl L-1 were added. The stable operation of the processes was achieved after 154 days when the nitrogen removal rate was 0.021 +/- 0.007 g N/L.d (corresponding to 30% of removal efficiency). To avoid the development of NOB activity at low salt concentrations and to stabilize the performance of the processes dissolved oxygen was supplied by intermittent aeration. A greater removal rate of 0.029 +/- 0.017 g-N L-1 d(-1) was obtained with direct exposure of the inoculum to 18 g-NaCl L-1 in less than 40 days. Also, higher specific activities than those from the inoculum were achieved for salt concentrations of 15 and 20 g-NaCl L-1 after 39 days of operation. This first study of the performance of the partial nitritation/anammox processes, to treat saline wastewaters, indicates that the acclimation period can be avoided to shorten the start-up period for industrial application purposes. Nevertheless, further experiments are needed in order to improve the efficiency of the processes. (C) 2017 Elsevier Ltd. All rights reserved.
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Melo, I. C., Alves, P. N., Queiroz, G. A., Yushimito, W., & Pereira, J. (2023). Do We Consider Sustainability When We Measure Small and Medium Enterprises' (SMEs') Performance Passing through Digital Transformation? Sustainability, 15(6), 4917.
Abstract: Small-medium enterprises (SMEs) represent 90% of business globally. Digital Transformation (DT) affects SMEs differently from larger companies because although SMEs have more flexibility and agility for adapting to new circumstances, they also have more limited resources and specialization capabilities. Thus, it is fundamental to measure SMEs' performance considering different perspectives. Here, we describe and analyze the state-of-the-art of DT in SMEs, focusing on performance measurement. We center on whether the tools used by SMEs encompass the triple bottom line of sustainability (i.e., environmental, social, and economic aspects). To do so, in December 2021, we performed a comprehensive systematic literature review (SLR) on the Web of Science and Scopus. In addition, we also explored a novel approach for SLR: topic modeling with a machine learning technique (Latent Dirichlet Allocation). The differences and interchangeability of both methods are discussed. The findings show that sustainability is treated as a separate topic in the literature. The social and environmental aspects are the most neglected. This paper contributes to sustainable development goals (SDGs) 1, 5, 8, 9, 10, and 12. A conceptual framework and future research directions are proposed. Thus, this paper is also valuable for policymakers and SMEs switching their production paradigm toward sustainability and DT.
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Melo, I. C., Queiroz, G. A., Junior, P. N. A., de Sousa, T. B., Yushimito, W. F., & Pereira, J. (2023). Sustainable digital transformation in small and medium enterprises (SMEs): A review on performance. Heliyon, 9(3), e13908.
Abstract: Small and medium enterprises (SMEs) are responsible for 90% of all business and 50% of employment globally, mostly female jobs. Therefore, measuring SMEs' performance under the digital transformation (DT) through methods that encompass sustainability represents an essential tool for reducing poverty and gender inequality (United Nations Sustainable Development Goals). We aimed to describe and analyze the state-of-art performance evaluations of digital transformation in SMEs, mainly focusing on performance measurement. Also, we aimed to determine whether the tools encompass the three pillars of sustainability (environmental, social, and economic). Through a systematic literature review (SLR), a search on Web of Science (WoS) and Scopus resulted in the acceptance of 74 peer-reviewed papers published until December 2021. Additionally, a bibliometrics investigation was executed. Although there was no time restriction, the oldest paper was published in 2016, indicating that DT is a new research topic with increasing interest. Italy, China, and Finland are the countries that have the most published on the theme. Based on the results, a conceptual framework is proposed. Also, two future research directions are presented and discussed, one for theoretical and another for practical research. Among the theoretical development, it is essential to work on a widely accepted SME definition. Among the practical research, nine directions are identified-e.g., applying big data, sectorial and regional prioritization, cross-temporal investigations etc. Researchers can follow the presented avenues and roads to guide their researchers toward the most relevant topics with the most urgent necessity of investigation.
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Nasirov, S., & Agostini, C. A. (2018). Mining experts' perspectives on the determinants of solar technologies adoption in the Chilean mining industry. Renew. Sust. Energ. Rev., 95, 194–202.
Abstract: The energy demand in Chile arises mostly from mining, its largest industry that accounts for about 35% of total electricity consumption. Energy generation to satisfy this demand depends completely on imported fossil fuels. As a result, the mining industry faces several energy related challenges. In particular, the cost and environmental impact of fuel sources are threatening the competitiveness of the industry and urge for new developments. In that regard, the importance of using clean and cost-competitive renewable energy sources has increased significantly in Chile and several government policies helped to increase the investment in them. The impact has been particularly large in the development of solar energy in the northern part of the country, where almost all mines are located. In fact, the country has become one of the largest solar markets in Latin America thanks to its abundant solar resources, favorable market conditions, and successful policy reforms. Solar energy then, could play a significant role as an alternative to satisfy the mining industry's energy demand offering a broad range of technological solutions. This study examines the key issues – barriers and drivers-influencing the adoption of solar technologies in the Chilean mining industry from the perspective of mining actors. As a result of the analysis the paper also provides a scope for appropriate policy interventions.
Keywords: Mining industry; Energy challenges; Solar energy; Chile
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Parrado, C., Girard, A., Simon, F., & Fuentealba, E. (2016). 2050 LCOE (Levelized Cost of Energy) projection for a hybrid PV (photovoltaic)-CSP (concentrated solar power) plant in the Atacama Desert, Chile. Energy, 94, 422–430.
Abstract: This study calculates the LCOE (Levelized Cost of Energy) on the PSDA (Atacama Solar Platform) for a solar-solar energy mix with the objective of evaluate new options for continuous energy delivery. LCOE was calculated for three 50 MW (megawatt) power plants: A PV (photovoltaic), a CSP (concentrated solar power) plant with 15 h TES (thermal energy storage) and a hybrid PV-CSP plant constituted with 20 MWp of PV and 30 MW of CSP with 15 h TES. Calculations present two scenario projections (Blue Map and Roadmap) until 2050 for each type of plant. Due to the huge solar resource available in northern Chile, the PV-CSP hybrid plant results to be a feasible option for electricity generation, as well as being effectively able to meet electricity demand profile of the mining industry present in the area. This type of energy could mitigate long-term energy costs for the heavy mining activity, as well as the country CO2 emissions. Findings point out that PV-CSP plants are a feasible option able to contribute to the continuous delivery of sustainable electricity in northern Chile. Moreover, this option can also contribute towards electricity price stabilization, thus benefiting the mining industry, as well as reducing Chile's carbon footprint. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords: LCOE; PV; CSP; Mining industry; Solar resource; Hybrid
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Rozas Andaur, J. M., Ruz, G. A., & Goycoolea, M. (2021). Predicting Out-of-Stock Using Machine Learning: An Application in a Retail Packaged Foods Manufacturing Company. Electronics, 10(22), 2787.
Abstract: For decades, Out-of-Stock (OOS) events have been a problem for retailers and manufacturers. In grocery retailing, an OOS event is used to characterize the condition in which customers do not find a certain commodity while attempting to buy it. This paper focuses on addressing this problem from a manufacturer’s perspective, conducting a case study in a retail packaged foods manufacturing company located in Latin America. We developed two machine learning based systems to detect OOS events automatically. The first is based on a single Random Forest classifier with balanced data, and the second is an ensemble of six different classification algorithms. We used transactional data from the manufacturer information system and physical audits. The novelty of this work is our use of new predictor variables of OOS events. The system was successfully implemented and tested in a retail packaged foods manufacturer company. By incorporating the new predictive variables in our Random Forest and Ensemble classifier, we were able to improve their system’s predictive power. In particular, the Random Forest classifier presented the best performance in a real-world setting, achieving a detection precision of 72% and identifying 68% of the total OOS events. Finally, the incorporation of our new predictor variables allowed us to improve the performance of the Random Forest by 0.24 points in the F-measure.
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Varas, M., Basso, F., Bosch, P., Contreras, J. P., & Pezoa, R. (2022). A horizontal collaborative approach for planning the wine grape harvesting. Oper. Res., 22(5), 4965–4998.
Abstract: Horizontal collaboration is a strategy that has increasingly been used for improving supply chain operations. In this paper, we analyze the benefits of using a collaborative approach when optimally planning the wine grape harvesting process. Particularly, we assess how labor and machinery collaborative planning impacts harvesting costs. We model cooperation among wineries as a coalitional game with transferable costs for which the characteristic function vector is computed by solving a new formulation for planning the wine grape harvesting. In order to obtain stable coalitions, we devise an optimization problem that incorporates both rationality and efficiency conditions and uses the Gini index as a fairness criterion. Focusing on an illustrative case, we develop several computational experiments that show the positive effect of collaboration in the harvesting process. Moreover, our computational results reveal that the results depend strongly on the fairness criteria used. The Gini index, for example, favors the formation of smaller coalitions compared to other fairness criteria such as entropy.
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Zuniga-Barra, H., Toledo-Alarcon, J., Torres-Aravena, A., Jorquera, L., Rivas, M., Gutierrez, L., et al. (2022). Improving the sustainable management of mining tailings through microbially induced calcite precipitation: A review. Miner. Eng., 189, 107855.
Abstract: Mining activities offers evident potential economic benefits for mineral rich countries. However, mining operations can produce a series of environmental impacts. Many of them are associated with the generation and management of tailings. Biogeochemical processes have potential to modify the properties of particulate solids, such as tailings. Microbial induced calcite precipitation (MICP) is probably the most studied biogeochemical process. It promotes calcite precipitation, as a result of biological activity of different microorganisms. Available research indicates that MICP is a tool that has the potential to contribute to a more sustainable management of tailing deposits. Indeed, MICP have been reported as a technology suitable for removal and/or immobilization of heavy metals, creation of impermeable barriers, prevention of soil liquefaction and control of windblown dust emissions. However, several challenges still need to be addressed to enable relible full-scale implementation, requiring research in the near future. These are consideration of the particular chemical composition of tailings, reduction of urea requirements, determination of optimal reagents dosage, evaluation of the long term stability of the treatment and calculation of costs associated to ecah particular application.
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