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BL.Optim: a configurable optimizer towards decision-making support for various scheduling and routing problem
No full textInternational audienceNowadays, there is a wide demand from many organizations to regularly route and schedule staff and goods to satisfy specific objectives. Scheduling and routing issues often require consideration of various businesses constraints under different industrial contexts, thereby ensuring the optimal use of resources. Decision-makers need customizable optimizers to specify business-oriented constraints and define their target planning generation needs. In our work, we present "BL.Optim", an optimizer with two-stage model-based architecture, which aims at capturing routing and scheduling requirement for a wide category of Constraint Satisfaction Problems (CSP). We demonstrated our approach on Home Health Care Routing and Scheduling Problems (HHCRSP), Home Meal Delivery Problems and Preventive Maintenance Scheduling and Routing Problems. The captured requirements are customizable by activating the necessary constraints facing the different realistic use cases. A series of CSP-based activable soft constraints and non-violated hard constraints are embedded in BL.Optim. To meet industrial requirements in solving the real-world cases with significant dimension, we opted for the Ant Colony Optimization algorithm for solution generation. Solutions generated by BL.Optim for HHCRSP are competitive against the manual scheduling result, with less 28% less assigned caregivers to perform required 142 services per day by respecting all the specified constraints
Sustainable management of plastic wastes in COVID-19 pandemic: The biochar solution
No full textInternational audienceTo prevent the COVID-19 transmission, personal protective equipment (PPE) and packaging materials have been extensively used but often managed inappropriately, generating huge amount of plastic waste. In this review, we comprehensively discussed the plastic products utilized and the types and amounts of plastic waste generated since the outbreak of COVID-19, and reviewed the potential treatments for these plastic wastes. Upcycling of plastic waste into biochar was addressed from the perspectives of both environmental protection and practical applications, which can be verified as promising materials for environmental protections and energy storages. Moreover, novel upcycling of plastic waste into biochar is beneficial to mitigate the ubiquitous plastic pollution, avoiding harmful impacts on human and ecosystem through direct and indirect micro-/nano-plastic transmission routes, and achieving the sustainable plastic waste management for value-added products, simultaneously. This suggests that the plastic waste could be treated as a valuable resource in an advanced and green manner
Clustering and exploring university students’ knowledge and attitude toward energy sustainability
No full textThe 8th International Conference on Energy and Environment Research ICEER 2021, 13–17SeptemberInternational audienceAn investigation of the attitudes and understanding of Indian university students, who are considered the country’s future workforce, was conducted to see if they could be classified into subgroups depending on their energy attitudes. The surveyed population was divided into four unique “personas”, each with a different level of engagement and a different perception of energy, using Hierarchical Cluster analysis. “Agents of Change”, “Mindful wanderer”, “Big talker”, and “Indifferent onlooker” were the four clusters identified. Energy knowledge was studied for fundamental energy themes, and the correlation test found a substantial positive relationship between energy knowledge and a person’s energy attitude. It also investigates how the findings on subgroups or personas can influence the construction of energy education curricula at different educational levels
Nanocellulose and its derivative materials for energy and environmental applications: Review
No full textInternational audienceThe application of biomass-derived renewable materials has generated great interest in recent research works. Among many such biopolymers, nanocellulose has become the leading topic in the sphere of sustainable material owing to the outstanding mechanical, chemical and thermal properties along with non-toxicity, surface functionality, ease of modification and sustainability. Nanocellulose is often considered to be a second-generation renewable resource and a better replacement for conventional petroleum-based products with or without any modifications. Even though some reviews have reported on some of the applications of nanocellulose, so far there is no comprehensive report gathering the extraction, properties, functionalization towards energy and environmental applications. This review aims to present the use of nanocellulose based materials for energy and environmental challenges. Important characteristics such as crystallinity, hydrophilicity, thermal decomposition and surface charge are described as a function of the targeted applications. In the latter part of this review, we have looked into the recent studies in the area of applications such as air pollution, heavy metal sorption, dye adsorption, biosensors, EMI shielding, fuel cell, solar cell, lithium-ion batteries and biofuels etc. However, a green, sustainable and scalable nanocellulose extraction is yet to be fulfilled. In our view, the bacterial nanocellulose based approach can address all these issues with the added advantage of producing a very high purity of nanocellulose. Hence this review is intended to provide new insights into the field of eco-friendly functional materials with included in-depth perspectives about nanocellulose and its future based on the current research trends
An original approach to assess the robustness of road freight transport plannings based on a dynamic risk identification
No full textInternational audienceThe road freight transport sector contributes significantly to the delivery of goods. Today, more than 90% of goods are conveyed using the road transport mode. In the same time, customers' requirements become more and more numerous and accurate, which increases the complexity of planner work. The aim of this work is to propose to planners robustness indicators measuring the chance the planned tour could respect the requirements. Based on a planning system giving several feasible daily schedules, our approach allows to dynamically identify the risks that could impact each planning and then simulate the influence of those risks on the plans' activities to assess the robustness indicators. They are composed of an indicator measuring the probability to respect the customers' requirements and two actionable data. These actionable data give to planners information on levers they could use to increase the robustness of the plan
Torrefaction of cellulose, hemicelluloses and lignin extracted from woody and agricultural biomass in TGA-GC/MS: Linking production profiles of volatile species to biomass type and macromolecular composition
No full textInternational audienceThe production of volatile species in torrefaction of cellulose, hemicellulose and lignin extracted from woody and agricultural biomass was quantified as a function of temperature. The novel coupling of TGA to GC/MS through a heated storage loop system allowed sampling volatile species released at 11 different temperatures in a single torrefaction experiment between 200 and 300 °C, at 3 °C.min−1. The results showed that the use of extracted fractions obtained from different biomass samples led to the detection of a higher number of species (23) than in previous studies with commercial compounds, obtaining a higher degree of detail in the characterization of the production of volatile species in torrefaction. Volatile species were generally released in this study from lower temperatures than those previously reported for commercial compounds. This may be due to the better preservation of cellulose, hemicellulose and lignin properties in extracted fractions thanks to the optimized extraction procedure. Volatile species production profiles were assessed based on the formation mechanisms proposed in the literature and the production of polysaccharide-based fractions was shown to be correlated to their sugar composition. Finally, production profiles allow identifying the temperature range to enhance the production of a given volatile species in torrefaction
Infrared thermography applied to the validation of thermal simulation of high luminance LED used in automotive front lighting: Review
No full textInternational audienceAutomotive front lighting evolved toward digital and adaptive high definition beams. In order to create such functions, multiple LED designs are replaced with new LED concepts involving only one high luminance LED. The luminous energy emitted by such a semiconductor light source, up to 3000lm (i.e. 10W), induces high density of energy up to 40W that requires to be thermally managed. Indeed, optical performances and reliability of components are directly linked to the LED temperature. Thus, accurate and efficient numerical models must be developed. In this paper, the validation of the high luminance LED thermal model is achieved by comparing numerical simulations with experimental data. The full characterization of the components is managed in order to build the corresponding thermal model. Then, a well-designed experimental set-up was developed to proceed to LED temperature measurement thanks to IR thermography, involving a camera equipped with a macro lens G1. A temperature uncertainty calculation is performed to introduce a tolerance range for the validation of the software. Finally, the commercial FVM software FloEFD™ is used to compute the LED thermal model. Numerical simulations are compared to experimental data. The agreement between computations and IR thermography is fair, which reinforces the use of the developed model with acceptable accuracy
Nifedipine dissolution rate improvement using supercritical carbon dioxide RESS and SAS process: application to transdermal delivery
No full textInternational audienc
The crucial role of the binder in biochar briquetting for sustainable energy production
No full textInternational audienceFossil-based CO2 emissions need urgently to be reduced to fight against global warming and the associated degradation of the environment. Biochar produced by biomass pyrolysis is a promising sustainable fuel alternative with a high fixed carbon and a relatively low volatile matter and ash content. However, densification is required to overcome its low density, which is the main inconvenient for its use. In this sense, briquetting forms biochar agglomerates with a suitable size, shape, density, composition and energetic content, which eliminates challenges associated with transportation, storage and handling of powdered material. In addition, it improves the fuel's energy density, hydrophobicity, mechanical strength and durability.The choice of the binder in biochar agglomeration is critical for guaranteeing optimal mechanical properties with fewer emissions and without compromising the calorific value. According to the literature, the most interesting binders for biochar densification include organic compounds, such as starch, molasses, lignin, and bio tar, and inorganic compounds, such as cement, clay, lime, plastic waste, and asphalt. Co-densification combining organic and inorganic binders would benefit from their synergic interaction leading to improved combustion and mechanical properties [1]. The operating conditions of the combustion process of the densified biosourced fuel need to be well controlled in terms of Quality, Health, Safety & Environment (QHSE). Common emissions are SO2, NOx, particulate matter, and volatile organic compounds (VOC). Their severity depends on the biomass type and the chemical composition of the briquette, including the binder [2].In this context, the aim of this study is to prepare and optimize the formulation of biochar briquettes from renewable raw materials and binders, so as to propose an alternative biosourced fuel. Preliminary results showed that biotar, starch and lime produce briquettes with high strength and high calorific value when properly formulated in the biochar composite
Desenvolvimento de implantes subcutâneos microestruturados de anfotericina B por spray-drying para tratamento local da leishmaniose cutânea.
No full textTherapy for localized cutaneous leishmaniasis (LCL) is based on multiple parenteral or intralesional (IL) injections with drugs that may cause severe systemic toxicity. Pain, malaise, and the need for frequent visits to distant medical centers are obstacles to adherence to treatment. Previously, our group showed the unprecedented use of biodegradable PLGA (poly-lactic co-glycolic acid) microparticles loaded with amphotericin B (AmB/PLGA) with a dual function of vectoring to infected skin macrophages and depot-controlled release, aiming the IL treatment of LCL in a single dose fashion. In this thesis, we proposed optimizing AmB/PLGA production using the spray-drying technique to allow fewer toxic solvents and scale-up production, different from the previously used method of solvent emulsification and evaporation. For differentiated distribution of AmB in the polymer matrix, sets of bi-fluid (matrix) and tri-fluid (core-membrane) nozzles were used, in addition to blends of PLGA with polylactic acid (PLA) or polyvinylpyrrolidone (PVP). Forty microparticles were produced, and some were physically characterized by SEM, DSC, FTIR, and Raman. Drug content and release rate were determined by spectrometry. For all selected AmB/PLGA microparticles, the average process yield was 50-90 %. SEM images showed spherical and rough topology. In vitro release kinetics using Franz cell permeation showed 65 % free AmB in 72 hours versus 10 % AmB/PLGA microparticles. DSC and FTIR studies observed that spray drying did not alter the physical-chemical characteristics of AmB or PLGA. Cytotoxicity studies appreciated that the different AmB/PLGA produced were not toxic to macrophages. Studies in vivo of cutaneous hypersensitivity (MEST) and histopathological analysis in mice treated with IL injections of AmB/PLGA found a small transient inflammation with increased TNF- α production. Efficacy studies in BALB/c mice infected in the pina ear with Leishmania amazonensis found that a single IL injection with AmB/PLGA better- controlled lesion growth and experienced a 5-fold parasite burden reduction compared to free AmB (Anforicin B®). In summary, this study shows the feasibility of using the scale-up spray-drying method with a tri-fluid nozzle to produce PLGA/AmB microparticulate implants in the IL treatment of cutaneous leishmaniasis.Non disponibleA terapia da leishmaniose cutânea localizada (LCL) é baseada em múltiplas injeções parenterais ou intralesionais (IL) com fármacos que podem causar grave toxicidade sistêmica. Dor, mal-estar e a necessidade de visitas frequentes a centros médicos distantes são obstáculos para adesão ao tratamento. Em estudos anteriores, nosso grupo mostrou o uso inédito de micropartículas biodegradáveis de PLGA (ácido poli-lático co-glicólico) carregadas com a anfotericina B (AmB/PLGA) com função dupla de vetorização para os macrófagos infectados da pele e depot de liberação controlada, visando o tratamento IL da LCL em dose única. Nesta tese, propusemos otimizar a produção de AmB/PLGA usando a técnica de spray-drying por permitir o uso de solventes menos tóxicos e ser escalonável industrialmente, diferente do método anteriormente utilizado de emulsificação e evaporação do solvente. Para distribuição diferenciada da AmB na matriz polimérica, foram utilizados conjuntos de bicos bi-fluido (matricial) e trifluido (núcleo-membrana) além de blendas de PLGA com ácido poli-lático (PLA) ou polivinilpirrolidona (PVP). Foram produzidas 40 partículas, das quais algumas foram selecionadas para serem caracterizadas fisicamente por MEV, DSC, FTIR e Raman. O teor e taxa de liberação do fármaco foram determinados por espectrometria. Para todas as micropartículas de AmB/PLGA preparadas, o rendimento médio do processo foi de 50-70 %, o tamanho médio na faixa de 10,6 - 17,3 μm, e teor médio do fármaco entre 50-90 %. Imagens de microscopia eletrônica de varredura (MEV) mostraram topologia esférica e rugosa. In vitro, a cinética de liberação usando permeação em células de Franz mostrou 65 % de AmB livre em 72 h contra 10 % das micropartículas de AmB/PLGA. Estudos de DSC e FTIR mostraram que o spray-drying não alterou as características físico-químicas da AmB ou do PLGA. Estudos de citotoxicidade mostraram que as diferentes AmB/PLGA produzidas não foram tóxicas para macrófagos. Estudos de hipersensibilidade cutânea (MEST) in vivo e análise histopatológica de camundongos tratados com injeções IL com AmB/PLGA mostraram uma pequena inflamação transitória com produção aumentada de TNF-α. Estudos de eficácia em camundongos BALB/c infectados na orelha comLeishmania amazonensis mostraram que uma única injeção IL com AmB/PLGA controlou bem melhor o crescimento da lesão e reduziu em 5 vezes a carga parasitária em comparação com a AmB livre (Anforicin B®). Em resumo, este estudo mostra a viabilidade do uso do método escalonável de spray drying com bico tri-fluido para a produção de implantes microparticulados de PLGA/AmB no tratamento da leishmaniose cutânea