No abstract

The negative effect caused by the degradation of nature and its ecosystems by the production of unbridled energy, drives in recent years the reduction of environmental impacts generated by high energy consumption through policies and proposals focused on the generation of rational energy. Although there are international laws and conventions in favor of energy sustainability, backed by international standards for energy management, such as ISO 50001, there is a lack of disclosure of cases of research studies focused on different entities that produce goods and services in countries developing. This paper presents the analysis of the electricity consumption of the University of Unicomfacauca in Popayán-Colombia, which leads to the generation of proposals for savings, energy efficiency and generation of photovoltaic energy for self-consumption; the first phase of the study consists in carrying out the energy inventory of the equipment and facilities; the second phase consists of the diagnosis, load inventory, macro consumption analysis and definition of energy saving and efficiency measures; the third phase involves the implementation of the proposed measures taking into account the cost benefit; the fourth phase, monitoring and evaluation of the measures implemented is carried out. The results show the model for the total monthly and annual electricity consumption, the energy analysis of the electrical system of the specified substations in maximum active power and apparent power, the load index and the electric power consumption; Likewise, the energy analysis of the lighting system and the viability of generating photovoltaic energy for self-consumption.

One of the main sources of economic income in Colombia's agricultural sector is the marketing of coffee with a high contribution to the country's economy. However, trends in coffee industry 4.0 show that the coffee roasting process is where more value aggregation is presented and at the same time is one of the most complex because multiple factors are involved such as grain moisture, volume, variety and heat and mass transfer variables. The main objective of this work was to design and implement a fluidized bed system for the study of the effect of temperature control on the physical properties of roasted coffee from Cauca-Colombia. The development of the work was addressed in 4 sequential phases: CAD design, Digital manufacture, temperature control design and the systems analysis. The proposed fluid bed system features a control system for the RoR (rate of rise) that can be adjusted between 3 to 20°C/min, and provide a prediction in the events of the standard roasting profile (Turning Point, Yellow, First Crack, Development time, Second Crack, Drop).

This investigation is concerned with the mechanical behavior of Shape Memory Alloy Hybrid Composite Beams (SMAHC), that consist of a circular bar of NiTi alloy incorporated in a 500 mm long cylindrical pipe of polypropylene (PP), with external diameter 50 mm and nominal wall thickness 7 mm, wound with a nylon/epoxy layer. The Ni-Ti alloy was characterized using: scanning electron microscopy (SEM); X-ray diffraction (XRD) and Differential thermal analysis (DSC). The nominal chemical composition of the alloy is 50.05 %Ni / 49.95%Ti, and the softer martensite is the predominant phase at room temperature. The approximate martensite (M) to Austenitic (A) phase transformation temperatures were Mstart = 32°C, Mfinal = 46°C, Astart = 38 °C and Afinal = 60°C. For temperature T<Mfinal, Ni-Ti bar presents 100% martensitic phase, whereas for T>Afinal it is fully converted in the Austenitic phase; and its elasticity modulus increases by a factor up to three times. This significant change in stiffness of Ni-Ti, without changing its mass, has motivated the application of such alloy in machine vibration control. The SMAHC beams were subjected to static three-point bending tests, in the elastic regime. Experimental results showed that, in average, at 21°C, the PP pipes effective flexural elastic modulus increased 112%, from 757 MPa to 1609 MPa, when the Ni-Ti bar and the external layer of nylon/epoxy were incorporated to the PP pipe, creating a smart beam. These last results indicate that the SMAHC beam can work as an adaptative structure.

The roasting coffee process is the compilation of time-temperature-dependent physical and chemical transformations induced by heat. Through the study of the time-temperature curve, the correct definition of the degree of roasting of coffee is an area of active and non-trivial research, which intervenes in obtaining consistent roasting profiles reflected in the acceptability of the drink perceived by consumers. This paper used the methodology of response surfaces (RSM) with the central composite design (CCD). A consumer study was conducted with 104 individuals, each tasting 13 cups of specialty coffee from Cauca-Colombia. Predictive equations for acidity and body perception were obtained. The roasting profile points in charge, turning point, yellow, brown, first crack, and drop step were included. Mathematical models predict the acidity and body perceptions by integrating the roasting profile points characteristics of coffee. The Cauca coffee beans produced using the optimied conditions contribute to obtaining a roasting time/ temperature of 468 s at 192 °C, respectively, with acidity (9/15) and body (5.5/15) in the (0-15) intensity consumer's perception scale.