Introduction: Conventional methods used to determine the strength of concrete have significant limitations in terms of time, costs, and operational efficiency. A 28-day curing period is required for a specimen to be considered ready for testing and its maximum strength to be measured. In addition, these traditional techniques involve the destruction of the samples after testing, which generates an irreparable loss of material and economic resources. This procedure not only increases project costs but also causes significant delays in the execution of the works, affecting their schedule, quality, and economic viability. Objective: Design a multiple linear regression model to predict the compressive strength of plain normal strength concrete at 7, 14 and 28 days. Methodology: Initially, information was collected on variables involved in the dosage of concrete and which influence compressive strength. For the training and testing stage of the model, the hold-out technique was used. The metrics used to evaluate the predictive capacity and validation of the model were R2, RMSE, MAPE. For the validation stage, laboratory tests of the materials were conducted, and concrete specimens were produced with a resistance of 240 kg/cm2 at 28 days, cured in the laboratory under controlled conditions. Results: The age of the concrete is the variable that presents the highest linear correlation value (0.648), of the 27 variables initially considered for the construction of the model, 13 were statistically significant for the model with 90% confidence. Conclusion: The analyses showed that the Multiple Linear Regression model generates acceptable predictions with a mean absolute percentage error of 7%. General Area of Study: Civil Engineering. Specific area of study: Materials. Type of study: Original articles.

Introduction. The energy crisis in Ecuador, driven by high dependence on hydropower and climate variability, has affected residential dwellings, with power outages, higher costs, and lower quality of life. This situation requires an effective response in terms of public policies and household energy consumption habits. Objective. To characterize energy consumption in residential dwellings in the Andean region of Ecuador, through the implementation of surveys and electricity consumption measurements, to identify energy efficiency patterns and opportunities that contribute to the reduction of energy consumption and the mitigation of the current energy crisis. Methodology. Surveys of residential households in Cuenca. Data was analyzed exploratorily. The assumptions of normality were verified with the Shapiro-Wilk test and homogeneity of variance with the Levene test. Statistical tests, t-tests and ANOVA were applied. In addition, linear regression was used to analyze the association between variables and energy consumption. Finally, clustering was applied. Results. Energy consumption is not associated with the type of housing, sector, socioeconomic level, size, expenses, the number of people, bathrooms, and bedrooms. The energy consumption profile does not show clear patterns in relation to the factors analyzed. The appliance with the highest energy demand in homes is the refrigerator. Conclusion. In Cuenca's residential homes, the average energy consumption is 84.8 kWh, with a variability of 17.5 kWh. A higher average consumption can be seen in apartments and in homes with a medium socioeconomic level. There are no significant patterns related to the type of housing or the socioeconomic level; however, the high consumption of the refrigerator suggests an opportunity to implement energy efficiency measures. General Area of Study: Energy and Sustainability. Specific area of study: Energy consumption. Type of study: Original article.

Introduction: A mineral extraction company located in the province of El Oro decided to begin implementing an environmental management system based on ISO 14001:2015 requirements. To do so, it analyzed each of the requirements in their content and subsequently designed a simple but effective methodology that met these requirements. The company decided to use requirement 4.1 (understanding the organization and its context) as a pilot test. The overall objective of this research was to develop a SWOT analysis proposal and a mineral extraction process diagram that complies with the ISO 14001 requirement, taken as a sample. This approach will serve to plan the entire management system, since requirement 4.1 (understanding the organization and its context) constitutes one of the most important guidelines for its overall environmental management. The methodology used was to create work teams with senior and middle management. Analysis and discussion sessions were held, and worksheets were used to collect information, which was then prioritized to work with the most relevant information. In the case of the process diagram, a block diagram was created that provided an overview of mineral extraction, and the inputs and outputs were subsequently identified and written, resulting in the final process diagram required for the company to continue with its ISO 1400 implementation. The results obtained were matrices that were simultaneously adjusted to what the requirement requested and resulted in a SWOT matrix detailing the external and internal issues relevant to the company's mission and that affect the expected results of the environmental management system as required by the requirement. The conclusion is that with the final deliverables obtained, the company fully complies with requirement 4.1: understanding of the organization and its context. It also has a general and accurate view of its business environment, as well as an internal description. All the above, with the idea that the company can subsequently determine its environmental objectives that will allow it to manage its environmental aspects and therefore prevent significant environmental impacts. General study area: Environmental Management Systems Specific study area: Compliance with requirement 4.1 of the ISO 14001 Standard: Type of article: Systematic bibliographic review.