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Countries with emerging legislation on the waste electrical and electric equipment (WEEE), but limited infrastructure, may find in other, more robust, systems the tools to develop adaptable and socioeconomically viable management schemes. Additives found in the plastics in electronic goods, such as brominated flame retardants (BFRs), are components of a safety system, but introduce characteristics that result in their waste being hazardous. Established and emerging regulatory systems need to implement legislation that impacts the management of WEEE, to reduce risks to human health and the environment, while maximising opportunities for resource recovery from widely varying materials. To assess the context of developed and emerging regulatory systems, a baseline study was undertaken of WEEE plastics in Scotland and Uruguay. For the identification of BFRs in plastics, an internationally validated screening methodology using X-ray fluorescence was adopted at different processing operations. It was observed that, using a threshold of 830 mg/kg for Br as a BFR tracer, in Scotland, more than 70% of the plastics would be recyclable, while, in Uruguay, that fraction dropped to 50%. These results, and the wider literature discussion, highlight the impact that regulatory frameworks have on the quality and recyclability of recovered material. We identify future actions to be considered by policy-makers for a more sustainable regulatory approach. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The application of mulching film has significantly contributed to improving agricultural output and benefits, but residual film has caused severe impacts on agricultural production and the environment. In order to realize the accurate recycling of agricultural residual film, the detection of residual film is the first problem to be solved. The difference in color and texture between residual film and bare soil is not obvious, and residual film is of various sizes and morphologies. To solve these problems, the paper proposes a method for detecting residual film in agricultural fields that uses the attention mechanism. First, a two-stage pre-training approach with strengthened memory is proposed to enable the model to better understand the residual film features with limited data. Second, a multi-scale feature fusion module with adaptive weights is proposed to enhance the recognition of small targets of residual film by using attention. Finally, an inter-feature cross-attention mechanism that can realize full interaction between shallow and deep feature information to reduce the useless noise extracted from residual film images is designed. The experimental results on a self-made residual film dataset show that the improved model improves precision, recall, and mAP by 5.39%, 2.02%, and 3.95%, respectively, compared with the original model, and it also outperforms other recent detection models. The method provides strong technical support for accurately identifying farmland residual film and has the potential to be applied to mechanical equipment for the recycling of residual film. [ABSTRACT FROM AUTHOR]

In this paper, the mixed refrigeration cycle of Skikda APCI (Air Products and Chemicals Inc.) process in Algeria was studied thermodynamically in order to determine the optimal operating conditions. The energy and exergy balance equations for each process component were established. The distribution of the exergy destruction of the basic cycle equipment revealed that the compressors had the highest exergy destruction rate. The effects of operating conditions on performance coefficient of the cycle (COP) and exergy efficiency of the APCI process were evaluated; mainly the inlet temperature of the compressors, natural gas (NG) temperature after cooling in the main cryogenic heat exchanger (MCHE) and inlet temperature of the mixed refrigerant (MR) expansion valve. The results of the numerical simulation validated using Aspen HYSYS software indicate that the COP and exergy efficiency of the basic cycle are 2.66 and 59.99% respectively. These results can be improved by reducing the inlet temperature of the compressor and the expander as well as that of the NG after cooling in the MCHE. Finally, the results of the optimization performed using the genetic algorithms (GA) are in agreement with those of the literature. They show signs of improvement in the COP and exergy efficiency of the APCI process by 1.48% and 3.64% respectively compared to the basic cycle. [ABSTRACT FROM AUTHOR]

The passive mobilization of the hand joints by means of dedicated equipment accelerates patient recovery and decreases significantly the costs of therapy. For this reason, research and development of such equipment is essential. Important reductions in the development cycle duration of such equipment can be achieved by means of a specific technique known as Model-Based Design. Starting from these considerations, this paper puts forward a Model-Based Design approach to the study of a new concept of rehabilitation equipment of the hand joints actuated by a pneumatic muscle. The originality of the paper consists in the MATLAB-based rendering of the functional model of the rehabilitation equipment actuation system and in the presented simulation results. The purpose of this research was to obtain information concerning the behavior of the proposed system and to predict its performance prior to it being built physically. After simulation, the results are compared to the operational performance of the experimental model. The conclusion shows that the proposed operational model describes accurately the actual behavior of the system and can be used for future optimization of the rehabilitation equipment. [ABSTRACT FROM AUTHOR]

Waste electrical and electronics equipment (WEEE) recyclers have become a boon for countries as they assist to reduce carbon emissions by recycling the WEEE in the most ecofriendly way. The evaluation and choice of optimal WEEE recycling partner is a significant and multifaceted decision for the managerial experts because of the involvement of several qualitative and quantitative criteria. Thus, the aim of the article is to propose a novel methodology by integrating a combined compromise solution approach and similarity measure within the context of single-valued neutrosophic sets (SVNSs) and, then, used to solve the decision-making problem. In this approach, the criteria weights are evaluated by a new procedure based on a similarity measure. For this, a novel similarity measure is introduced for SVNSs and also presented its efficiency over existing similarity measures. To investigate the efficiency and practicality of the introduced approach, a case study of WEEE recycling partner selection is taken under the SVNSs environment. Finally, comparison and sensitivity analysis are made to check the robustness and stability of the developed methodology. The outcomes of this article exemplify that the developed approach is more suitable and well consistent with existing approaches. [ABSTRACT FROM AUTHOR]

The active digitalization of the healthcare system has given impetus to the emergence of a new type of enterprise—high-tech medical organizations (HMO). Their main distinguishing feature is the use of innovative high-tech medical equipment. However, the high cost of this equipment has become a factor slowing down the development of such organizations. This paper considers the life-cycle contract (LCC) as a special form of interaction between stakeholders and investments throughout the life cycles of equipment. Moreover, to provide technological support, continuous acquisition and life-cycle support (CALS) technologies, which are based on the same principles of working with the life cycle as LCC, are proposed. This question turned out to be a significant research gap, which was not sufficiently reflected in the available world studies. Thus, the aim of the current study is to describe the features of the use of LCC for HMO using CALS technologies and the impact of the life cycle of high-tech medical equipment on LCC, as well as to present the innovative component of the proposed model. Based on the analysis of the literature and the best world practices, the authors propose a visualization of the interaction of all stakeholders within the LCC for HMO. Such a decision is extremely relevant for developing organizations, public authorities and investors around the world. [ABSTRACT FROM AUTHOR]

This study aimed to compare the status of implementation of the Solid Waste Management (SWM) in the Municipality of Candijay, Bohol, Philippines for the year 2015 and 2020 to find ways for the sustainability of the implementation of the Town's Solid Waste Management. Wastes were collected monthly for one year from the five sampled barangays with 122 households. Field investigations, on-site waste measurements and characterizations were conducted. This is a mixed method employing QUANT-Qual approach. Descriptive statistics which include percentages, and weighted mean were used for the quantitative approach while narrative analysis for the qualitative was used. The results revealed that from the previous data of SWM implementation found out that the average biodegradable waste generated in the year 2015 which was 46.14% decreased to 10.94% as a result of home proper waste disposal. Likewise, the recyclable waste which had 27.27%, the number decreased to 26.08%. Since residual wastes should be collected, the collection increased to 59.85% from 15.42% due to acquisition of additional garbage trucks. For special waste, from 11.16% previously collected, it decreased to 3.13%. There was significant difference between the biodegradable, residual and special wastes. In the present SWM implementation, innovation played an important role in recycling waste materials. Shredded plastics and crashed glasses were converted into mixture to create concrete products. The shredded biodegradable wastes were converted into organic fertilizers. The produce out of these shredded materials were used to generate income which played an important role to sustain the solid waste implementation. Thusly, the level of implementation was already properly practiced. Solid Waste Management had employed organizational structure for implementation and dissemination of personnel's function. Additional equipment and personnel were acquired. To sustain the proper SWM, recycling equipment, public awareness, funding, expertise of personnel, equipment and facilities, innovations and other provisions must be provided. [ABSTRACT FROM AUTHOR]

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The dismantling and recycling of junction boxes, which is an important part of the photovoltaic module recycling process, was tested and designed scientifically. The equipment framework was built by three-dimensional simulation, and then the design of dismantling and recycling equipment for junction boxes of waste crystal silicon photovoltaic modules was completed through the experimental test and data analysis. The experimental results show that the initial idea of the dismantling scheme is correct, and the structure is feasible. However, some problems were not considered. This study provides reliable data support for the subsequent equipment development and ensures the smooth development of the subsequent design work. [ABSTRACT FROM AUTHOR]

The steel industry has had a great boom with the passage of time since it expanded with industrialization, many are those who have experimented in facilitating the production of steel from iron as a mineral, because its manufacture is expensive and is required in different economic sectors. The production process of this industrial sector generates environmentally polluting waste, which has been the subject of study; that is why recycling was used as an input for this type of industry, obtained from disused items, known as scrap, including ferrous and non-ferrous objects, being the interest of the iron and steel industry those containing iron and steel. Thus, since the 40's, ferrous scrap has been included as a raw material in the manufacturing process of the steelworks and it is necessary to determine how this element impacts the process, Therefore, a bibliographic review was carried out to provide the advantages and a priori studies of different experiences in the world with this input and to prove that it contributes positively not only to the steel industry but to the world in general. It was concluded that the recycling of post-consumer equipment favors the environment, reduces costs in the manufacturing process and minimizes the mining exploitation of iron and other elements. [ABSTRACT FROM AUTHOR]

Bioelectrochemical systems (BESs) use electrochemically active microorganisms to convert the chemical energy of organic matter into electrical energy, hydrogen, or other useful products through redox reactions. Microbial electrolysis cell (MEC) is one of the most common BESs which are able to convert organic substrate into energy (such as hydrogen and methane) through the catalytic action of electrochemically active bacteria in the presence of electric current and absence of oxygen. In the past decades, BESs have gained growing attention because of their potential, but there is still a limited amount of research is done for the environmental effects of BESs. This study initially provides an update review for MECs including general historical advancement, design properties, and operation mechanisms. Later, a life cycle assessment (LCA) study was conducted using a midpoint approach, which is TRACI methodology with EIO-LCA model to identify the potential impacts to the environment whether adverse or beneficial using the MECs to produce hydrogen with domestic wastewater as a substrate. The results show that the cumulative negative impacts were substantially larger than the positive impacts by contrast with the expectations, and the cumulative output data show that human health non-cancer impact provides the highest environmental effects than others mainly because of the inorganic chemicals, pumping and wastewater recycling equipment step. In addition, global warming potential and smog creation potential are also elevated mainly due to electricity usage, inorganic chemical and glassware reactor production. Later we are externally normalized each impact category to compare the results at the normalization level, and we again found that human health (cancer or non-cancer) potential provides the most negative impact on the environment in the MEC system originates on human health indicators. [ABSTRACT FROM AUTHOR]

From a practical point of view, a turbine load cycle (TLC) is defined as the time a turbine in a power plant remains in operation. TLC is used by many electric power plants as a stop indicator for turbine maintenance. In traditional operations, a maximum time for the operation of a turbine is usually estimated and, based on the TLC, the remaining operating time until the equipment is subjected to new maintenance is determined. Today, however, a better process is possible, as there are many turbines with sensors that carry out the telemetry of the operation, and machine learning (ML) models can use this data to support decision making, predicting the optimal time for equipment to stop, from the actual need for maintenance. This is predictive maintenance, and it is widely used in Industry 4.0 contexts. However, knowing which data must be collected by the sensors (the variables), and their impact on the training of an ML algorithm, is a challenge to be explored on a case-by-case basis. In this work, we propose a framework for mapping sensors related to a turbine in a hydroelectric power plant and the selection of variables involved in the load cycle to: (i) investigate whether the data allow identification of the future moment of maintenance, which is done by exploring and comparing four ML algorithms; (ii) discover which are the most important variables (MIV) for each algorithm in predicting the need for maintenance in a given time horizon; (iii) combine the MIV of each algorithm through weighting criteria, identifying the most relevant variables of the studied data set; (iv) develop a methodology to label the data in such a way that the problem of forecasting a future need for maintenance becomes a problem of binary classification (need for maintenance: yes or no) in a time horizon. The resulting framework was applied to a real problem, and the results obtained pointed to rates of maintenance identification with very high accuracies, in the order of 98%. [ABSTRACT FROM AUTHOR]

In this research, the performance of serial two-stage compression (STC) cycle and bypass two-stage compression (BTC) cycle on the household refrigerator-freezers is tested in the laboratory. Then, based on the results of the experiments, exergy, exergoeconomic analyses, and cycle optimization are carried out. Considering that replacing refrigerants in household refrigerator-freezers is one of the approaches to increase the performance and environmental impact of these systems, R436A refrigerant (46% Isobutene and 54% Propane mixture) is used and analyzed to replace previous refrigerants. Finally, the multi-objective optimization of the mentioned cycles is performed with both refrigerants. For analyses, two models of refrigerator-freezers with different cycles are used (STC cycle with R134a refrigerant and BTC cycle with R-600a refrigerant). In both models, two evaporators for refrigerator-freezer compartments are used. International standards (IEC 62552) are used to test refrigerator-freezers. MATLAB and REFPROP 9.1 software are used to model the systems. According to the results of the analyses, the STC cycle with R436A refrigerant has more total exergy destruction rate (0.727 kW) compared to R134a refrigerant. In the BTC cycle, in which the fresh food compartment (FFC) and freezer compartment (FZC) operate, the total exergy destruction rate with R-600a refrigerant (0.422 kW) is less than with R436A refrigerant. In the case of the BTC cycle in which only the FZC operates, the total exergy destruction rate with R-600a refrigerant (0.455 kW) is less than with R436A refrigerant. The most exergoeconomic factor among cycle equipment is related to the compressor (about 98%). The highest COP value between cycles is related to the STC cycle with R134a refrigerant. [ABSTRACT FROM AUTHOR]

Introduction: In Cuba, chemical industry is characterized by low profitability, ineffective technological investments, a high number of failures, and high operating costs. This is due to the lack of foresight and technical evaluations of aspects related to reliability, maintainability and availability. Objective: To propose an evaluation and improvement procedure for reliability, maintainability and availability of the industry, during its life cycle. Materials and Methods: Used tools and methods such as reliability, maintainability, availability and criticality were analyzed, and their influence on various stages life cycle of an equipment or system was incorporated in this analysis. Results and Discussion: A procedure that integrates a group of techniques and tools was proposed, in order to apply them throughout the facilities life cycle, which will allow predicting and minimizing the occurrence of stoppages due to failures, as well as the identification of the most critical areas and equipment. Conclusions: This procedure covers the entire life cycle of an equipment or installation, facilitates decision-making according to the industry stage when repairing or replacing equipment or installation and enables the generation of maintenance policies to be applied for the optimization of operational and stadium costs. [ABSTRACT FROM AUTHOR]

A die for Al alloy casting must be designed to achieve the expected quality levels. Moreover, the casting unit cost must be regarded as the objective function to be minimised. It can be expressed as a function of the quantity of materials and energy to be used, cycle time and equipment investment. This work compares the performance of the die with inserts manufactured using the usual 1.2343 steel with that of the innovative 1.2383. The latter is considered due to its enhanced thermal conductivity, despite being more expensive. Simulation experiments are designed to evaluate different die layouts. The quality design solutions are evaluated against the cost objective function in order to identify the optimal die choice. A case study on gravity die casting (GDC) of an AlSi7Mg0.3 engine head shows faster solidification dynamics when using 1.2383 instead of 1.2343 steel. This reduces the feeder volume, thus increasing the production yield and speeding up the cycle time with a leverage effect. The higher investment cost for the inserts is rapidly returned thanks to the reduction in variable costs. The Return On Investment (ROI) with the improved die in the new solution is short compared with the life of the die. [ABSTRACT FROM AUTHOR]