1,721,018 research outputs found
Facility layout problem: Bibliometric and benchmarking analysis
Full text linkFacility layout problem is related to the location of departments in a facility area, with the aim of determining the most effective configuration. Researches based on different approaches have been published in the last six decades and, to prove the effectiveness of the results obtained, several instances have been developed. This paper presents a general overview on the extant literature on facility layout problems in order to identify the main research trends and propose future research questions. Firstly, in order to give the reader an overview of the literature, a bibliometric analysis is presented. Then, a clusterization of the papers referred to the main instances reported in literature was carried out in order to create a database that can be a useful tool in the benchmarking procedure for researchers that would approach this kind of problems
Coffee biowaste valorization within circular economy: an evaluation method of spent coffee grounds potentials for mortar production
Full text linkPurpose: Spent coffee grounds (SCG) are biowastes extensively generated within the coffee supply chain. Nowadays, their disposal represents an increasing environmental concern due to its toxicity and organic nature. With the estimated increase of coffee production and consumption in the upcoming years, there is an imperative need to find a proper reverse option, along with a novel industrial application, which allows for the valorization of this coffee by-product within a circular economy perspective. This study aims at investigating a potential reuse of spent coffee grounds to produce novel construction materials to be used for sustainable buildings. Methods: After having illustrated the forward flows within the coffee life cycle and the potential reverse flow options, an evaluation method based on multi-criteria analyses was elaborated to test not only the technical but also the environmental and economic performances of novel materials originating from the incorporation of SCG as an aggregate in natural hydraulic lime and geopolymer-based mortars. Moreover, we focus on the reuse of another waste streams— biomass fly ash—deriving from the paper-pulp industry, rarely investigated in both traditional construction applications and in geopolymer manufacture. The two (geopolymer- and lime-based) mortar typologies are here studied and compared as potential green material for applications in construction, with satisfying engineering performance and high insulation attitude, giving a new life to a common organic waste. Consequently, we compare eight formulations by means of multi-criteria approaches that are nowadays claimed as a useful and effective decision aiding support instrument to assess the development of new sustainable construction materials. They permit to consider simultaneously some controversial and often uncertain aspects like technological (as the usual scientific studies do), environmental, and economic (more difficult to easily approach and evaluate). For this purpose, in this paper, we have analyzed the performance of the novel bio-composite mortars using VIKOR and TOPSIS methods to rank a set of alternatives according to various evaluation criteria that often conflict one with each other. Results: Results show that adding spent coffee grounds can efficiently improve the technical and sustainable performances of the novel mortars for different applications in the building sector. The presence of SCG increases water absorption and improves the insulation performance along with an environmental impact reduction. The considered technological properties are highly promising—such as the improvement in thermal insulation. In particular, even the addition of only 5% SCG leads to a significant reduction of the thermal conductivity and consequently to a greater insulating performance. Conclusions: To date, most of the available literature on recycling SCG in construction materials do not consider mortar-based applications and, moreover, nor multi-criteria approaches. Therefore, our study proposes itself as an innovative track solution to food waste management lowering the employment of non-renewable natural resources and the costs associated to construction material production. At the same time, a novel and innovative way of such waste disposal is suggested, pursuing the sustainability and substantially reducing the environmental impact of construction and building materials. This study is a fundamental step in assessing the applicability of our designed and produced materials and its potentials to be produced at an industrial scale
From lab to industry: Scaling up green geopolymeric mortars manufacturing towards circular economy
No full textConstruction is nowadays considered an extremely energy intensive industry and one of the main sources of environmental pollution in the world. Therefore, the research and the development of novel energy-saving manufacturing processes and sustainable construction materials is more than ever urgent and challenging. This paper aims at identifying the industrial process for the production of novel geopolymers to be used as a greener substitute for cement, especially the Portland one, widely used for structural applications to significantly reduce the environmental impact of the construction industry. Here, the materials sustainability and the manufacturing process are improved by valorising and reusing wastes, deriving from the pulp-paper industry, as raw materials. This industry generates a great quantity of wastes that represent a real concern both for their environmental impact and cost of disposal. The new industrial process was evaluated after scaling up the laboratory procedure to an industrial dimension. Consequently, each small-scale process was deeply analysed (raw materials involved and processes) and transposed into a massive-production. The most relevant processes that show an elevated environmental impact were identified and the energy consumption of the whole process has been assessed resulting, for the analysed geopolymeric product, an embodied energy of 645 MJ/ton, being about one sixth of the OPC. Moreover, a preliminary economic analysis has been conducted in terms of raw materials involved in the proposed industrial process revealing a decreasing cost per ton increasing the waste recycling. All considered, the main conclusions are that the industrial scale up of the proposed geopolymeric product, assessed for the first time in literature along with the related proposed considerations, could be highly competitive to the Portland production involving greener processes with a much lower energy consumption and a greater financial saving by improving the wastes quantity
Microbial-based cleaning products as a potential risk to human health: A review
No full textMicrobial-based cleaning products (MBCPs) have been introduced, on the market, as an alternative to traditional chemical cleaning. In addition to traditional detergents, MBCPs can perform their cleaning function, digesting the smallest particles of dirt and mitigating odours generated by environmental bacterium metabolic processes. Nevertheless, several aspects remain to be clarified and assessed, requiring further studies and new regulations to ensure safety. The particular composition of MBCPs makes it difficult to include these products in a specific class, making the European legal context incomplete and unclear. Moreover, MBCPs effects on human health are poorly documented. Exposure risks can be obtained indirectly by studies conducted in both microorganisms exposure and their metabolic products, such as enzymes, especially in workers. A further limiting factor for the accurate human health risk assessment due to MBCPs use is an incomplete indication about the MBCPs compositions. Moreover, additional factors such as host microorganisms, frequency and space of use, subject health condition, and age can determine different illness scenarios. The findings from the broad range of studies we have reviewed in this paper confirm the necessity of integrative investigation and regulation to address the use of MBCPs
Multi criteria evaluation of a sustainable alkali-activated concrete
No full textThe construction industry is one of the most polluting sectors worldwide. In order to reduce the environmental footprint, novel green materials and processes are being considered by valorising and reusing wastes. This work investigates the production of a novel and sustainable geopolymeric concrete reusing biomass fly ash from kraft paper-pulp industry. In particular, this paper aims to evaluate the best combination of the aggregate granulometry used in the material production. For this purpose, the multicriteria method TOPSIS has been implemented in order to obtain a rank of the concrete specimens. In this approach only mechanical aspects have been considered and future developments will include criteria related on the buildings environmental conditions. The environmental conditions during in site exposure could in fact vary the performance achieved by the materials in laboratory test and GIS software could be a useful tool to combine information about quality material components and environmental condition
ELECTRE TRI-based approach for sorting projects portfolio: Focus on the European strategy
Full text linkThe European Framework Programme for Research and Innovation aims to facilitate the collaboration between public and private sectors in delivering innovation. To achieve this goal, Union Research and Innovation Programme provides various financial instruments, among which the Horizon 2020 is one of the most significant. Since its implementation, the Horizon 2020 has stimulated the interest of several research organizations making the partnerships among companies their core business for improving local economy. In this context, technological districts are the main proponents of research and innovation spreading in the local territory. In Sicily, the AgroBioPesca district exploited these opportunities, undertaking the strategic “Call for ideas” proposal with the aim of building its own roadmap for research and innovation. To such an aim, AgroBioPesca collected several innovative project ideas coherent with some Technological Trajectories (TT) provided by Horizon 2020 and in line with the national and local operational programmes. These project ideas have been evaluated by a technical and scientific committee, taking into account specific criteria related to the Horizon 2020 technical guidelines. This paper aims to select the AgroBioPesca best projects portfolio by applying the multiple criteria sorting method (MCSM) ELECTRE TRI. A sensitivity analysis has lastly been conducted in order to verify the robustness of the solutions obtained
Firefly algorithm based upon slicing structure encoding for unequal facility layout problem
Full text linkFinding the locations of departments or machines in a workspace is classified as a Facility Layout Problem. Good placement of departments has a relevant influence on manufacturing costs, work in process, lead times and production efficiency. This paper analyses the problem of allocating departments with restrictions in terms of unequal area and rectangular shape within a facility, in order to minimize the sum of material handling costs taking into account the satisfaction of the aspect ratio requested. In particular, we propose for the first time a Firefly Algorithm based on the slicing structure encoding. The proposed method was tested comparing the results obtained from other authors on the same literature instance. The results confirm the effectiveness of the Firefly Algorithm in solving the Facility Layout Problem by generating the best solutions with respect to those provided by previous researches. (C) 2019 by the authors; licensee Growing Science, Canad
Evaluation of new functional pasta using TOPSIS methodology
No full textNowadays several studies are focused on the introduction of Opuntia in frequently consumed foods, such as pasta and bakery products. Food products containing Opuntia are in fact able to reduce body weight and plasma LDL cholesterol, lipids and glucose. Foods, that may provide health and wellness benefits, are known as "functional foods". The aim of this paper is the evaluation of a new functional pasta comprising Opuntia able to guarantee health benefits without altering the organoleptic properties of the final product. For this purpose, a set of samples, based on different concentration of Opuntia solution and process parameters, was prepared for the production of short and long pasta. The choice of the best sample was achieved by using a Multi-Criteria Decision-Making (MCDM) procedure in order to consider the quality of the final product and the production cost. In particular, Technique Ordered Preference by Similarity to the Ideal Solution (TOPSIS), one of the most widely used MCDM methods in decision support systems, was here implemented
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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