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In the present study, the development of pigmented cement mortar for outdoor applications, aiming to replace traditional finishes, especially in pool settings, was investigated. The study used the properties of workability, particle size, and strength from a commercial sample (CS) as a reference, complying with regulations for pool finishes. In the initial stage, the additive/binder (A/B) and water/cement (W/C) ratios were varied to achieve workability similar to the CS reference. Compression strength and porosity were evaluated as response variables according to ASTM C642 standards at 1, 7, and 28 days of curing. In a subsequent stage, the aggregate/cement ratio was reduced to enhance mechanical performance and reduce porosity. Additionally, colorants were introduced, and compression strength at 1, 7, and 28 days, three-point flexural strength, and the percentage of permeable pores at 28 days were assessed. Pigmented mortars exhibited compressive strengths exceeding 35 MPa, flexural strengths exceeding 5 MPa, and a volume percentage of pores below 8% after 28 days of curing. [ABSTRACT FROM AUTHOR]

In the new global economy, the transport system has become a central issue to the public policy design. This article presents a model of vehicle technology adoption that determines the probability of technology selection. A system dynamics and Analytic Hierarchy Process (AHP) approach was used to analyze the adoption of electric vehicle technologies from the Colombian market. Previous research has tended to focus on environmental impact rather than the political, economic, and infrastructure one. The model considers the interaction of market share, political, and infrastructure variables that interact in the transport system. The study proves a novel approach related to modeling strategy, segmentation of the Colombian vehicular market, and results of market scenarios, including peace agreements, economic growth, and infrastructure. The results allow us to understand the relevance and impact of alternative policies on penetration of non-conventicnal technologies (electric vehicles) in Colombia. [ABSTRACT FROM AUTHOR]

The increase in environmental pollution and oil prices and the depletion of reserves to meet future demand have forced researchers to develop new alternative sources of fuel for mobility. This article discusses the infrastructure and environment impact assessment of electric vehicles (henceforth EVs) through a model for EVs massiflcation in Bogota, D.C., based on models of system dynamics, which takes into account the interaction of variables whose condition changes over time. The article presents the outcomes of the potential impact on infrastructure and environment due to the massiflcation of EVs in Bogota, D.C. The design of the model of massiflcation of EVs takes into account the characteristics of vehicles and users' needs in the city. Based on this model, the increase in EVs and its impact on infrastructure and environment for the next 20years were estimated. [ABSTRACT FROM AUTHOR]

Increasing air pollution, increasing oil prices and diminishing oil reserves all together lead to the search of alternative fuels for mobility. This paper proposes an EV (Electric Vehicle) massification projection model for the city of Bogota, based on a dynamic system methodology. A three steps model was formulated: first step considers technical and economic requirements for different EV technologies, a second step includes the massification model proposed and the final step consider a projection for EV quantity. Results of an EV massive deployment potential study for Bogota are presented. The EV massive use projection model here presented considering both the needs of potential users and EV's features; the proposed model also analyzes four different EV technologies considered as four different future scenarios. A growth of 2% to 8% in Bogota's EV fleet for the next 20 years has been estimated by applying this model. [ABSTRACT FROM AUTHOR]

This paper contains the analysis of the impact, performance, and effect on power quality of the semi-fast charging cycle of electric vehicles (EVs) within the electrical grid. The results allowed to obtain an electric model of the EV charging cycle. The procedures and results of tests on the DC semi-fast charging cycle of EVs used for the public transportation in Bogota D.C. are presented. Some tests to the EV charging cycle were applied in steady state in order to evaluate the performance and the power quality of EVs. The fact that the charging system has a total harmonic current distortion (THDi) of 7% and a total harmonic voltage distortion (THDv) that satisfactorily comply with local and international regulations is highlighted. Tests were performed in transient state of the charger and their analysis was done by using Continuous Wavelet Transform (CWT). Results in transient state of the beginning of the DC charging cycle of EVs reveal that the harmonics of greater impact are 3°, 4°, and 5°. Finally, based on the analysis of the presented results, a simulation profile of the charging system was designed using the Matlab Sim Power Systems tool. The obtained model shows an error of 2% compared to measurements in steady state. This model will be useful in decision-making on the processes of system planning in case that EVs will be massified within the public transportation in Colombia. [ABSTRACT FROM AUTHOR]

This paper presents the impact evaluation of a possible massive implementation of EV charging facilities over the electric distribution grid of Bogota, Colombia. Chargers are represented using a model based on tests with real charging systems. Likewise, the topologies used are based on existing networks. The simulation method adopted offers the possibility of comparing different charging scenarios for each studied network. The main evaluation criteria are: voltage behavior in the nodes, voltage regulation and changeability of the distribution transformers. Simulation results are given by comparing quantitative values obtained via progressive inclusion of chargers in the distribution network. The presented values depict three different scenarios: office use (slow daytime charging), residential use (slow nighttime charging) and commercial use (semi-fast daytime charging).The impact on the distribution network produced by massive EV recharge depends mainly on the behavior of users: start time and duration of recharge. [ABSTRACT FROM AUTHOR]

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