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Construction with recycled aggregate concrete – Influence on design and construction of reinforced concrete structures Apart from the need to reduce huge quantities of CO2 emitted in cement production in particular, an efficient use of diminishing natural resources such as sand and gravel is indispensable for a more eco efficient concrete production. In this context, the use of recycled aggregates seems to be a promising alternative to natural aggregates in conventional concrete to save natural resources. Since 1998, the use of recycled aggregate in structural concrete is allowed in Germany following the guideline issued by the German Committee for Structural Concrete (DAfStb). With the new edition of Eurocode 2 (FprEC2), regulations for the use of recycled aggregate concrete (RAC) are also included for the first time. Starting with the properties of RAC compared to natural aggregate concrete (NAC), the current regulations for design of RAC are compared and an outlook on future research focussing not only resource efficiency but also CO2 emission reduction in concrete production is given. [ABSTRACT FROM AUTHOR]

The use of energy by society is increasing and is not matched by the availability of raw materials. Fuel oil and coal are dwindling and even running out. Therefore, to overcome this problem the government issued Presidential Regulation No. 5 of 2006 concerning the National Energy Policy, where the utilization of biofuels is targeted at 2% in 2010 and 5% in 2025. To overcome this, methods are carried out by using renewable fuels and processing residual production materials such as the use of bagasse waste as fuel. Electrical energy sources from PLN and power plants in Indonesia are the main sources of electricity distribution used by consumers (industry). At PG. Kebon Agung has its own 4 steam power plants to meet the electrical energy needs needed to drive production machinery. Utilization of bagasse has the potential as a renewable fuel as a substitute for coal to gain resource and cost efficiency. In this study, the authors attach a cost comparison to the use of bagasse with other fuels, a comparison of the use of electrical energy from PLTU with PLN, and waste treatment to get efficiency and benefits in terms of costs and natural resources. With this research, it is hoped that readers can save resources and increase the efficiency of using biomass fuels. [ABSTRACT FROM AUTHOR]

Collective self-consumption is called to be a crucial part of the current energy transition. In addition to the advantages of individual self-consumption, the possibility of improving economic feasibility exists. This paper shows how matching production and consumption loads increase the rate of self-consumption. Still, how the electricity is distributed among a renewable energy community's prosumers would reduce the total costs of self-consumed energy. Possible criteria for the allocation of the generated electricity among shareholders are analysed. The study also evaluates the use of static and dynamic distribution coefficients, observing their results and applicability and sorting them to maximise self-consumption participants' savings. The results are questioned against them and a reference scenario without shared self-consumption installation. As the exploitation of renewable energy for self-consumption is closely linked to the energy market and regulations, the analysis is based on a territorial case study. It is shown that the highest savings occur when electricity is allocated following distribution coefficients that consider the customer's energy consumption better than investment participation or contracted power, even when the compensation of surpluses is added. These criteria can accomplish technical and economic objectives and are introduced in regulations that foster the requested changes in consumers' behaviour and prosumers for sustainability. [ABSTRACT FROM AUTHOR]

Collective self-consumption is called to be a crucial part of the current energy transition. In addition to the advantages of individual self-consumption, the possibility of improving economic feasibility exists. This paper shows how matching production and consumption loads increase the rate of self-consumption. Still, how the electricity is distributed among a renewable energy community’s prosumers would reduce the total costs of self-consumed energy. Possible criteria for the allocation of the generated electricity among shareholders are analysed. The study also evaluates the use of static and dynamic distribution coefficients, observing their results and applicability and sorting them to maximise self-consumption participants’ savings. The results are questioned against them and a reference scenario without shared self-consumption installation. As the exploitation of renewable energy for self-consumption is closely linked to the energy market and regulations, the analysis is based on a territorial case study. It is shown that the highest savings occur when electricity is allocated following distribution coefficients that consider the customer’s energy consumption better than investment participation or contracted power, even when the compensation of surpluses is added. These criteria can accomplish technical and economic objectives and are introduced in regulations that foster the requested changes in consumers’ behaviour and prosumers for sustainability.

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The energy saving potential is related directly to the increase of gas application efficiency. Herewith, energy use efficiency is a complex concept, including not only the issues of technological efficiency, but also the requirements for the economic, social and environmental components of the processes. Meanwhile, the problem of energy efficiency assessment is a more general problem of effective use of resources in comparison with alternative energy and resource-using processes, reduced to comparable analysis conditions. In addition, efficiency should be distinguished from the point of view of consumers, producers and suppliers of energy resources, as well as from the point of view of general economic (state) efficiency.

New ventures must rigorously manage their resources because they suffer from the liabilities of newness and smallness. Digitalization, traditionally associated with resource savings, higher operational efficiency and more flexibility, implies great benefits for new ventures; however, this effect has not been empirically proven. Implementing the resource-based view, this article uses a survey with 102 new ventures to investigate how new ventures benefit from digitalization. We clustered the new ventures in three groups according to their degree of digitalization (low, medium or high) and conducted an analysis of variance to compare the benefits of digitalization among these groups. Our results show that a higher degree of digitalization in new ventures does not result in direct resource savings such as decreased human capital or office space needed; rather, it results in indirect savings through increased operational efficiency. It also leads to considerably greater market flexibility. Our findings assist founder and founder support initiatives in evaluating the necessity of investing in digitalization given the benefits realized. [ABSTRACT FROM AUTHOR]

How can cities, businesses and industries boost growth in the face of resource scarcity? Firstly, they can start by measuring their consumption in order to manage it more effectively. Then, all of us can to move away from a linear model of consumption. We can accelerate this transition today, thanks to IoT*, the digital revolution.At Veolia, we are the first to monitor and to optimize water, energy and material flows in real-time. We are developing smart monitoring centers called Hubgrade relying on connected products and artificial intelligence. With these centers, we are creating new jobs and business opportunities to save resources.Hubgrade boosts energy efficiency and water conservation measures. It optimizes material recovery and maximizes the use of renewable energy. However, this is only possible, with the focus on the human factor. * IoT – Internet of Things

The construction sector uses various metals like steel (for frames, reinforced concrete), iron (wrought iron for beams, trusses, girders), aluminium (ceiling and walls, window frames, HVAC systems etc.) and copper (cladding, electrical wiring, oil & gas lines). Due to increasing pressure on various resources like energy, chemicals and raw materials, economic edge can be sustained only through high resource efficiency. Adopting resource efficient cleaner production (RECP) measures will improve economic and environmental performance, including reducing greenhouse gas emissions; in turn, this will make them less vulnerable to changes in external conditions and more competitive. With co-funding from the EU SWITCH-Asia Programme, the project METABUILD (www.metabuild-southasia.org) aims at implementing sustainable production processes and practices in 400 SMEs across Bangladesh, Nepal and Sri Lanka besides creating a conducive environment for further adoption of sustainable production processes in the metal products supply chain for the building and construction sector. In Nepal, the project has already engaged with 82 metal industries. These cover different sectors such as fabrication, wire drawing, electrical cables, re-rolling, galvanizing/electroplating, casting etc. and are in multiple locations viz. Kathmandu, Lalitpur, Morang, Sunsari, Rupandehi, Bara, Parsa, Kaski districts. RECP measures such as use of daylight, replacement of inefficient lights by LED lights, power factor improvement, furnace modification, waste heat recovery, insulation etc. have been implemented. These have led to savings in energy and raw materials, at the same time reducing generation of wastes from these participating industries and improvement of occupational health and safety (OHS). This paper will explain the mode of engagement with industries, details of the resource efficiency measures implemented and estimated saving. [ABSTRACT FROM AUTHOR]

• Dataset of plates lifetime were obtained by 3 casting methods and chemical composition. • A two-steps model for prediction of the full lifetime of plates of Hadfield steel was proposed. • The prediction model combines regression trees with multilayer perceptron (MLP) • MLP provides accurate weaŕs models considering the chemical composition. • Regression trees provide visual information about dataset structure to build MLP. Highly tensile manganese steel is in great demand owing to its high tensile strength under shock loads. All workpieces are produced through casting, because it is highly difficult to machine. The probabilistic aspects of its casting, its variable composition, and the different casting techniques must all be considered for the optimisation of its mechanical properties. A hybrid strategy is therefore proposed which combines decision trees and artificial neural networks (ANNs) for accurate and reliable prediction models for ore crushing plate lifetimes. The strategic blend of these two high-accuracy prediction models is used to generate simple decision trees which can reveal the main dataset features, thereby facilitating decision-making. Following a complexity analysis of a dataset with 450 different plates, the best model consisted of 9 different multilayer perceptrons, the inputs of which were only the Fe and Mn plate compositions. The model recorded a low root mean square error (RMSE) of only 0.0614 h for the lifetime of the plate: a very accurate result considering their varied lifetimes of between 746 and 6902 h in the dataset. Finally, the use of these models under real industrial conditions is presented in a heat map, namely a 2D representation of the main manufacturing process inputs with a colour scale which shows the predicted output, i.e. the expected lifetime of the manufactured plates. Thus, the hybrid strategy extracts core training dataset information in high-accuracy prediction models. This novel strategy merges the different capabilities of two families of machine-learning algorithms. It provides a high-accuracy industrial tool for the prediction of the full lifetime of highly tensile manganese steel plates. The results yielded a precision prediction of (RMSE of 0.061 h) for the full lifetime of (light, medium, and heavy) crusher plates manufactured with the three (experimental, classic, and highly efficient (new)) casting methods. [ABSTRACT FROM AUTHOR]

Svenson (2011) showed that choices of one of two alternative productivity increases to save production resources (e.g., man-months) were biased. Judgments of resource savings following a speed increase from a low production speed line were underestimated and following an increase of a high production speed line overestimated. The objective formula for computing savings includes differences between inverse speeds and this is intuitively very problematic for most people. The purpose of the present studies was to explore ways of ameliorating or eliminating the bias. Study 1 was a control study asking participants to increase the production speed of one production line to save the same amount of production resources (man-months) as was saved by a speed increase in a reference line. The increases judged to match the reference alternatives showed the same bias as in the earlier research on choices. In Study 2 the same task and problems were used as in Study 1, but the participants were asked first to judge the resource saving of the reference alternative in a pair of alternatives before they proceeded to the matching task. This weakened the average bias only slightly. In Study 3, the participants were asked to judge the resources saved from each of two successive increases of the same single production line (other than those of the matching task) before they continued to the matching problems. In this way a participant could realize that a second production speed increase from a higher speed (e.g., from 40 to 60 items /man-month) gives less resource savings than the same speed increase from a first lower speed (e.g., from 20 to 40 items/man-month. Following this, the judgments of the same problems as in the other studies improved and the bias decreased significantly but it did not disappear. To be able to make optimal decisions about productivity increases, people need information about the bias and/or reformulations of the problems.

The essence of the economic mechanism of resource savings and the reasons of the relationships between them are defined in this article. Also the place and the role of each of the blocks are analyzed.

The most important aspect of sustainability in manufacturing is the preservation of energy and natural resources. For modern production, optimized processes that minimize negative impacts on the environment are becoming increasingly important. This can be achieved by increasing energy efficiency through low, clean, and renewable energy consumption. There are many ways to produce less pollution, emissions, and waste in machining: by using more environmentally friendly cooling methods; by applying methods that reduce or eliminate the need for utilization of cooling lubrication; improving the energy efficiency of machining operations; determining the optimal cutting conditions that save resources by increasing machining productivity or reducing the metal removal rate (MRR); minimizing power consumption; and reducing carbon dioxide emissions. This article gives an idea of modern manufacturing with a focus on analyzing the current state of machining operations in terms of saving production resources and ensuring more environmentally friendly production using greener cooling methods of machining such as Dry, Conventional cooling systems, Minimum quantity of lubricant (MQL), Minimum quantity of cooling lubrication (MQCL), Nanofluids, Biodegradable Vegetable Oils, Cryogenic Lubrication, and High-Pressure Cooling (HPC). Finally, the important modern trends of providing resource-saving and environmentally efficient technologies in modern sustainable manufacturing are discussed in this paper. • Present review article deals with the sustainability and resource saving aspects during machining operations. • Different cooling conditions were presented. • Waste minimizing, recycling, pollution etc. were discussed during machining oeprations. [ABSTRACT FROM AUTHOR]

Svenson (2011) showed that choices of one of two alternative productivity increases to save production resources (e.g., man-months) were biased. Judgments of resource savings following a speed increase from a low production speed line were underestimated and following an increase of a high production speed line overestimated. The objective formula for computing savings includes differences between inverse speeds and this is intuitively very problematic for most people. The purpose of the present studies was to explore ways of ameliorating or eliminating the bias. Study 1 was a control study asking participants to increase the production speed of one production line to save the same amount of production resources (man-months) as was saved by a speed increase in a reference line. The increases judged to match the reference alternatives showed the same bias as in the earlier research on choices. In Study 2 the same task and problems were used as in Study 1, but the participants were asked first to judge the resource saving of the reference alternative in a pair of alternatives before they proceeded to the matching task. This weakened the average bias only slightly. In Study 3, the participants were asked to judge the resources saved from each of two successive increases of the same single production line (other than those of the matching task) before they continued to the matching problems. In this way a participant could realize that a second production speed increase from a higher speed (e.g., from 40 to 60 items /man-month) gives less resource savings than the same speed increase from a first lower speed (e.g., from 20 to 40 items/man-month. Following this, the judgments of the same problems as in the other studies improved and the bias decreased significantly but it did not disappear. To be able to make optimal decisions about productivity increases, people need information about the bias and/or reformulations of the problems. [ABSTRACT FROM AUTHOR]

Abstract: A methodology for estimation of natural resource savings due to fly ash utilization in road construction in India is presented. Analytical expressions for the savings of various resources namely soil, stone aggregate, stone chips, sand and cement in the embankment, granular sub-base (GSB), water bound macadam (WBM) and pavement quality concrete (PQC) layers of fly ash based road formation with flexible and rigid pavements of a given geometry have been developed. The quantity of fly ash utilized in these layers of different pavements has also been quantified. In the present study, the maximum amount of resource savings is found in GSB followed by WBM and other layers of pavement. The soil quantity saved increases asymptotically with the rise in the embankment height. The results of financial analysis based on Indian fly ash based road construction cost data indicate that the savings in construction cost decrease with the lead and the investment on this alternative is found to be financially attractive only for a lead less than 60 and 90km for flexible and rigid pavements, respectively. [Copyright &y& Elsevier]

The new fertilization program in Villa Clara provides each time more fertilizer recommendations for sugar-cane growing. It begins with the reception of soil samples up to issue the recommendations at field level, including soil analysis and its control. The use of this program (based on the experience of agrochemical service) allows cane growers to save resources, mainly fertilizer carriers, so as it helps to preserve soil, avoiding its deterioration. Another major characteristic of this program is the instauration of a monitoring network of the fertilizer recommendations, which allows, if it is necessary, to make corrections on time. It is an automated system, so that human errors are reduced to a minimum at making recommendations. Automation is not only applied in the software for fertilizer necessities, but for all soil lab calculations as well. [ABSTRACT FROM AUTHOR]

• Strategy kept setpoints when either cooling or heating was needed in the greenhouse. • Fogging lowered VPD and ventilation lowered enthalpy while heating increased it. • Transpiration cooled the greenhouse air by adding up to 84.5% of the water vapor. • Control not effective when it wasn't psychrometrically possible to reach setpoints. Climate in greenhouses is continuously influenced by the outside environmental conditions. Outside conditions are always variable, especially in locations with extreme climates. Under non-extreme climates, greenhouses equipped with natural ventilation systems coupled with on–off controllers may be sufficient to effectively maintain appropriate climate conditions for plant growth. However, additional and flexible climate control systems, such as variable frequency drive (VFD) controllers, may be needed under extreme environments. In this study, the performance of a greenhouse climate control strategy, which considers plant transpiration, includes heating, operates variable vent configurations and a fogging system on a VFD basis, was tested by computer simulations. The strategy uses a set point of air specific enthalpy (55.8 kJ kg−1) to control the heaters and vents while a set point of Vapor Pressure Deficit (VPD) of 1.0 kPa is used to control the fogging system. Simulations were performed for two locations with different climates to test the strategy's capabilities. Set points were effectively maintained whenever cooling demands existed in the greenhouse. For that, the crop played a key role by adding to the atmosphere on average 55.14 and 84.53% of the water vapor by means of plant transpiration for the first and second locations, respectively. When demands for heating existed, the set points were maintained whenever it was psychrometrically possible. When the outside air is at high humidity levels, the set points cannot be achieved under this approach. Under such conditions, the set points may be continuously and simultaneously kept if a dehumidification action is added to the strategy. [ABSTRACT FROM AUTHOR]