Tecnura

13-28

Authors: Fredy Alberto Amaringo Villa, Angelina del SocorroHormaza

Context:Agricultural residues have become uncon-ventional adsorbents of great interest due to their wide availability, minimum cost, and high efficien-cy. In this work, the adsorbent capacity of rice husk by-product (RH) in the Red 40 (R40) anionic dye re-moval was evaluated under a discontinuous system. Method: For determining the best conditions for the removal of this dye, a factorial design 23 was im-plemented, which allows to achieving a removal of 75.6% at pH = 2.0, an initial concentration of 15 mg/L, dosage of 8.0 g/L, and contact time of 18 hours. Results: The equilibrium, kinetics and thermody-namic properties of the process were evaluated. It was found that the Langmuir model best represents the experimental results with qmax of 2.74 mg/g and an adjustment coefficient of R2=0.987. Regarding kinetics, the pseudosecond order model with qt of 1.09 mg/g presented the best fit (R2 = 0.970). Finally, Gibbs free energy (ΔG = -1.11 KJ/mol) and entropy (ΔS = 23.9 J/mol*K) indicate a spontaneous pro-cess, while enthalpy showed that the removal of R40 constitutes an endothermic process, with ΔH = 6.71 KJ/mol. Furthermore, the activation energy of 14.1 KJ/mol suggests that the mechanism of adsorption of the R40 takes place through a physi-adsorption. Conclusions: These results indicate that the rice husk offers an adequate adsorbent capacity for the reten-tion of azo dye of contaminated effluents; besides, scaling up this process is feasible given its thermo-dynamic characteristics.

40 - 50

Authors: William Sáenz Rodríguez, Fernando Rivera Sánchez, Fernando Martínez Santa

Context: This paper is presents the design and imple-mentation of an 8-bit softcore RISC microprocessor able to be run on space-optimized FPGA, in order to be used for embedded applications. Method: The design of this microprocessor was de-veloped in Verilog hardware description language and can be implemented in FPGA from different manufacturers; therefore, the user has only to defi-ne the input and output ports according to the type of FPGA. This is an accumulator-type processor, but it has two different accumulators that can be used as pointers for indirect addressing. The processor is Harvard with a RAM of 8x256 bits, and a ROM that can be resized from 17x252 bits to 17x8K bits. Addi-tionally, it has one 8-bit input port, one 8-bit output port, and one 8-bit address port, which means that the processor can address more than 256 8-bit ou-tput and input ports/devices. Results: The developed processor, named “ZA-SUA,” was compared with PICOBLAZE softcore and other three similar processors of free distribution in the Web, and some improvements over those were found. Criteria such as the Flip Flops used, occupied LUTs, Slices in use, and maximum delay of each processor were analyzed, all these results were ob-tained from the implementation of the processors in the Xilinx FPGAs. Conclusions: The designed architecture is composed by two accumulators, which can be used either as source or destination for the operation of the ALU. This fact gives some flexibility to the design, doing it better than a single-accumulator processor, and get-ting it closer to the register-based processors

62 - 75

Authors: Espinel Duarte Luis Eduardo, Ladino Chaves Oswaldo, Iguarán Salinas Lauren Diane.

Context:This study presents the weak infrastructure that exists on long-haul roads. The municipality of Cachipay, Cundinamarca, is taken as a case study, which does not escape a series of mobility inconve-niences due to the failures of the road network. Method: The research was developed in the line of investigation of modeling and simulation of pro-blems, with the approach of a case study through inventory and damage analysis, developing two al-ternatives, and choosing the most appropriate one Results:The search for solutions to mobility problems in the municipality of Cachipay has generated an in-crease in vehicular traffic through the streets of the municipality, ranging from 67% to 46%, according o traffic counts recorded on weekdays against the holidays. Conclusions: Because it is a municipality near the ca-pital, Cachipay ought to have proposals that contribute to solve the deterioration of the streets and alternate roads, and to strengthen the municipal vehicle fleet