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Evaluation of thermal and spectroscopic properties of hybrid biocomposite OPW/ramie fiber for materials building

AIP Conference Proceedings 2023年第1期2554卷

作者： Indra Mawardi Samsul Rizal Sri Aprilia Muhammad Faisal 1Doctoral Program School of Engineering Post Graduate Program Universitas Syiah Kuala Banda Aceh 23111 Indonesia 2Department of Mechanical Engineering Politeknik Negeri Lhokseumawe Lhokseumawe 24301 Indonesia 3Department of Mechanical Engineering Universitas Syiah Kuala Banda Aceh 23111 Indonesia 4Department of Chemical Engineering Universitas Syiah Kuala Banda Aceh 23111 Indonesia

Environmentally friendly and sustainable buildings encourage researchers to develop natural fiber-based building materials. This investigation was prompted by the abundance of oil palm wood and the fact that it is rarely used as a building material. This study aims to investigate the thermal and spectroscopic properties of a hybrid bio-composite based on oil palm wood as a candidate for green building materials. The hybrid composite was fabricated from oil palm wood and ramie fiber as reinforcement and tapioca starch as a matrix. Oil palm wood particles and ramie fiber were pretreated in 100°C water and NaOH solution, respectively. Hybrid biocomposite was fabricated using hotpress at constant temperature and pressure, with variations of HBC1, HBC2, HBC3 and HBC4. Evaluation of thermal properties in thermogravimetric analysis, differential scanning calorimetry, and spectroscopic was carried out. Thermogravimetric and spectroscopic analysis showed that the HBC3 sample was more stable up to the temperature 358°C and the bigger crystal size is 3.45 nm, compared to other samples. These results showed that oil palm wood-based hybrid composites have the potential to be used as green building materials.

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An efficient multi-objective evolutionary approach for solving the operation of multi-reservoir system scheduling in hydro-power plants

arXiv

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arXiv 2021年

作者： Marcelino, Carolina Gil Leite, G.M.C. Delgado, C.A.D.M. De Oliveira, L.B. Wanner, E.F. Jiménez-Fernández, S. Salcedo-Sanz, S. Department of Signal Processing and Communications Universidad de Alcalá Spain Institute of Computing Federal University of Rio de Janeiro Brazil Post-Graduate Program in Systems Engineering and Computer Science Federal University of Rio de Janeiro Brazil Computing Department Federal Center of Technology Education of Minas Gerais Brazil

This paper tackles the short-term hydro-power unit commitment problem in a multi-reservoir system - a cascade-based operation scenario. For this, we propose a new mathematical modelling in which the goal is to maximize the total energy production of the hydro-power plant in a sub-daily operation, and, simultaneously, to maximize the total water content (volume) of reservoirs. For solving the problem, we discuss the Multi-objective Evolutionary Swarm Hybridization (MESH) algorithm, a recently proposed multiobjective swarm intelligence-based optimization method which has obtained very competitive results when compared to existing evolutionary algorithms in specific applications. The MESH approach has been applied to find the optimal water discharge and the power produced at the maximum reservoir volume for all possible combinations of turbines in a hydro-power plant. The performance of MESH has been compared with that of well-known evolutionary approaches such as NSGA-II, NSGA-III, SPEA2, and MOEA/D in a realistic problem considering data from a hydro-power energy system with two cascaded hydro-power plants in Brazil. Results indicate that MESH showed a superior performance than alternative multi-objective approaches in terms of efficiency and accuracy, providing a profit of $412,500 per month in a projection analysis carried out. © 2021, CC BY-NC-ND.

关键词： Multiobjective optimization

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Grid-Forming MMC: A Comparison Between Single- and Dual-Loop Control Approaches

Grid-Forming MMC: A Comparison Between Single- and Dual-Loop...

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Brazilian Power Electronics Conference, COBEP

作者： Cleiton M. Freitas Edson H. Watanabe Luís F. C. Monteiro Rio de Janeiro State University Rio de Janeiro Brazil Electrical Engineering Program - COPPE Federal University of Rio de Janeiro Rio de Janeiro Brazil Post-Graduate Prog. of Electronic Eng. Rio de Janeiro State University Rio de Janeiro Brazil

ISBN: (纸本)9781665421300

This work presents an analysis of the grid-forming Modular Multilevel Converter (MMC), in the frequency domain, when it is controlled through single or dual-loop implementation. The dual-loop approach presents an inner current-loop control gathered with the external voltage-loop control, whereas the single-loop only presents a voltage-loop control for the grid-forming capability. In both cases, the control algorithms were implanted in a natural reference frame, including resonant controllers. The paper follows an impedance-modeling approach for introducing the analytical representation of the MMC in the frequency domain. These representations are, in fact, the linearized Teéenin-equivalent models of the single- and dual-loop grid-forming MMC. The results showed that the inner current-loop control is a feasible approach for damping specific resonant peaks of the Thevenin-equivalent impedance. In other words, the current-control loop adds a resistive parcel in MMC impedance in the frequency range in which the resonant peaks appear. As a consequence, the LC resonance between this impedance and the capacitor bank in the main bus is damped. The article also contains some switching-level EMTDC/PSCAD simulations to validate the work.

关键词： Damping Analytical models Shape Frequency-domain analysis Capacitors Resonant frequency Switches

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Application Alkali Treatment Rice Husk - CaCl2 as Moisture Absorber of Coconut Palm Sugar Granule 6

Application Alkali Treatment Rice Husk - CaCl2 as Moisture A...

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6th International Conference on Sustainable Agriculture, Food and Energy: Inclusive Agri-Food Energy Production for Community Empowerment in a Changing Climate, SAFE 2018

作者： Agriawati, D.P. Warsiki, E. Iskandar, A. Noor, E. Post Graduate Program of Agroindustrial Technology Bogor Agricultural University Bogor Indonesia Department of Agroindustrial Technology Faculty of Agricultural Engineering and Technology Bogor Agricultural University Bogor Indonesia

Rice husk is high fiber agricultural wastes and with CaCl2 impregnated, it would be potential to develop as a composite moisture absorber. In this case, the rice husk - CaCl2 composite can absorb and control the moisture in headspace of packaging to stabilize the water activity of the product. This study was aimed to develop moisture absorber from rice husk - CaCl2 and apply the sachet of moisture absorber into the package of coconut palm sugar granule (CSG). Moisture absorber was prepared by impregnated the surface of modified rice husk using sodium hydroxide (5% w/v) and CaCl2 with the concentration of 5, 10 and 15 % w/v. Physical parameters of CSG were analyzed. Rice husk - CaCl2 15% has the highest moisture absorption. Meanwhile, the using of rice husk - CaCl2 as moisture absorber was able to maintain the moisture content of CSG during storage at the condition as about 2% with RH 70%. © 2019 IOP Publishing Ltd. All rights reserved.

关键词： Chlorine compounds

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A new Normalized Index for Ranking Papers in Systematic Literature Reviews

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Decision Analytics Journal 2024年 10卷

作者： Steffen, Vilmar de Oliveira, Maiquiel Schmidt Brusamarello, Claiton Zanini Trojan, Flavio Academic Departments of Engineering (DAENG) Federal University of Technology - Parana (UTFPR) Rua Gelindo Joao Folador 2000 Parana Francisco Beltrao 85602-863 Brazil Academic Department of Physics Statistics and Mathematics (DAFEM) Federal University of Technology - Parana (UTFPR) Rua Gelindo Joao Folador 2000 Parana Francisco Beltrao 85602-863 Brazil Academic Department of Electronics (DAELE) Federal University of Technology - Parana (UTFPR) Rua Doutor Washington Subtil Chueire 330 Parana Ponta Grossa 84017-220 Brazil Post-graduate Program in Production Engineering (PPGEP) Federal University of Technology - Parana (UTFPR) Rua Doutor Washington Subtil Chueire 330 Parana Ponta Grossa 84017-220 Brazil

The number of journals, and consequently the number of papers, has grown significantly, which makes it necessary to use suitable tools in systematic literature reviews. Several methodologies have been proposed for this purpose, and one of these methods is the index calculation used to rank the papers in order of importance. This study proposes a new index called the Normalized Index for Ranking Papers to rank the papers in a systematic literature review, which is considered mainly indicators provided by the Centre for Science and Technology Studies journal indicators. For this index calculation, importance weights are assigned by the researchers, and the indicators used in the index are normalized. For ranking the final portfolio, the proposed method considers a weighted average of indicators (impact factors) in which the paper was published and a value that represents approximately the number of citations per year. The journal self-citation index benefits the journals with lower self-citation practices. A Systematic Literature Review (SLR) was carried out to analyze the final portfolio's results involving Multi-criteria Decision Analysis in airports. The indicators normalization enables the importance of each metric to be decided by the researcher according to the choice of the weights, not by the difference in the indicators’ magnitude. The importance of an article can be proved initially by the journal indicators in which the paper was published and by citations per year. © 2024 The Authors

关键词： Importance weight Journal indicator Multiple criteria Normalized Index for Ranking Papers Rank index Systematic Literature Review

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Solid State Fermentation of Rice Straw Pulp with a Local Trichoderma reesei for Single Cell Protein Production: Effects of Temperature, Initial Medium pH and Fermentation Time

Solid State Fermentation of Rice Straw Pulp with a Local Tri...

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International Conference on Science and Innovated engineering 2018, i-COSINE 2018

作者： Novita, E. Zaki, M. Said, S.D. Post-Graduate Study Program Chemical Engineering Department Faculty of Engineering Syiah Kuala University Darussalam-Banda Aceh23111 Indonesia Chemical Engineering Department Faculty of Engineering Syiah Kuala University Darussalam-Banda Aceh23111 Indonesia

Indonesia is one among countries that produce abundant of rice straw every year generated as post-harvesting residue from paddy field all over country. This abundant amount residue is highly potential to be utilized as carbon source in producing single cell protein (SCP) in solid state fermentation system. SCP is a microbial protein that can be used as alternative protein for substitution of available conventional protein sources such as;fish meal, soy bean, and corn Stover for animal feed production. This research was conducted to evaluating the effects of initial medium pH of substrate (mixed rice straw pulp-urea), fermentation time and fermentation temperature on SCP production by Trichoderma reesei in solid state fermentation (SSF). The results showed that the highest SCP yield (19.71%) was produced at the initial medium pH of 5 and temperature of 30 °C at SSF conditions of C/N ratio 20:1 for 12 days of fermentation time. © Published under licence by IOP Publishing Ltd.

关键词： Urea

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Effects of Ultraviolet-Enhanced Ozonation on Degradation of Ammonia and Urea in Fertilizer Plant Wastewater

Effects of Ultraviolet-Enhanced Ozonation on Degradation of ...

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International Conference on Science and Innovated engineering 2018, i-COSINE 2018

作者： Muhammad Yusuf, A.R. Mulana, Farid Said, Syahiddin Dahlan Post-Graduate Study Program Chemical Engineering Department Syiah Kuala University Darussalam-Banda Aceh23111 Indonesia Chemical Engineering Department Syiah Kuala University Darussalam-Banda Aceh23111 Indonesia

Ammonia and urea contained in fertilizer plant wastewater are pollutants to the environment. High concentration of ammonium and urea in wastewater can affects algae blooms in ecosystem which will generate various diseases in aquatic biota. It is known that there are many methods for degradation of ammonium and urea contained in fertilizer plant wastewater. One of potential method is ultraviolet-enhanced ozonation. Ozonation is oxidation with O3 that generates hydroxyl radicals which subsequently react with organic contaminants, while UV irradiation can break down O3 molecules and produce radical ions OH. The objectives of this study were to examine the effects of the utilization of the ultraviolet-enhanced ozonation method in degradation of various initial ammonium (100-300 ppm) and urea concentration (100-300 ppm) in inlet feed of ozonation-UV irradiation combination system. Some important variables such as contact time (0-120 minutes) and ozone feed rate of 0.2, 0.6, and 1.21 g/h were evaluated. Degradation process was carried out in two steps;ozonation and UV irradiation. Ozonation process was carried out in a contacting tank at constant feed flow rate of 1.5 l/min and at room temperature, while UV irradiation process was conducted in pipeline equipped with UV lamp at various contact time. The ultraviolet-enhanced ozonation could degraded ammonium and urea nitrogen up to 83.6% and 63.8%, respectively, at ozone feed rate 1,21 g/h, contacting time 60 and 120 min, initial feed concentration of ammonia (100 ppm) and urea (40 ppm). © Published under licence by IOP Publishing Ltd.

关键词： Ozonization

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Effects of ultraviolet-enhanced ozonation on the degradation of ammonia and urea in fertilizer plant wastewater

Effects of ultraviolet-enhanced ozonation on the degradation...

引用

International Conference on Science and Innovated engineering 2018, i-COSINE 2018

Ammonia and urea contained in fertilizer plant wastewater are pollutants to the environment. High concentration of ammonium and urea in wastewater can affects algae blooms in the ecosystem which will generate various diseases in aquatic biota. It is known that there are many methods for degradation of ammonium and urea contained in fertilizer plant wastewater. One of the potential method is ultraviolet-enhanced ozonation. Ozonation is oxidation with O3 that generates hydroxyl radicals which subsequently react with organic contaminants, while UV irradiation can break down O3 molecules and produce radical ions OH. The objectives of this study were to examine the effects of the utilization of the ultraviolet-enhanced ozonation method in degradation of various initial ammonium (100-300 ppm) and urea concentration (100-300 ppm) in inlet feed of ozonation-UV irradiation combination system. Some important variables such as contact time (0-120 minutes) and ozone feed rate of 0.2, 0.6, and 1.21 g/h were evaluated. Degradation process was carried out in two steps;ozonation and UV irradiation. Ozonation process was carried out in a contacting tank at a constant feed flow rate of 1.5 l/min and at room temperature, while UV irradiation process was conducted in pipeline equipped with a UV lamp at various contact time. The ultraviolet-enhanced ozonation could degrade ammonium and urea nitrogen up to 83.6% and 63.8%, respectively, at ozone feed rate 1,21 g/h, contacting time 60 and 120 min, initial feed concentration of ammonia (100 ppm) and urea (40 ppm). © Published under licence by IOP Publishing Ltd.

关键词： Urea

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Fuzzy sports motivational system for measuring psychological and training issues in running recreational practice and adherence

Fuzzy sports motivational system for measuring psychological...

引用

Decision Aid Sciences and Application (DASA), International Conference on

作者： Vanessa C. M. Ribeiro Ernesto Araujo Biomedical Engineering Post-Graduate Program Universidade Anhembi Morumbi (UAM) SP Brazil Universidade Anhembi-Morumbi (UAM) São Paulo SP Brazil Centro de Inovação Tecnologia e Educação (CITE) SP Brazil Inteligência Artificial em Tecnologia (IATECH) SP Brazil

ISBN: (纸本)9781665416351

A fuzzy system for assessing sports adherence and practice by taking into account motivational training and psy-chological factors for recreational runners is proposed in this paper. Running is a sport that has continuously been increasing and recreational runners, mostly characterized by amateur ath-letes, are characterized as presenting diverse and multifaceted profile. Such running sports practitioners present interests from promotion of health and attending races up to achieve social interaction and obtain pleasant moments. In consonance with this perspective, the proposed fuzzy IF-THEN system is designed by employing psychological and practice aspects to assess the level of interest, motivation, and adherence of recreational runners. In this sense, the fuzzy inference system uses as linguistic input variables the psychological level of satisfaction concerning the training in group (collective training) and coach's professional expertise (professional quality of the coach), two prominent motivation factors among recreational sports practitioners. The fuzzy set theory and fuzzy logic is used to represent the subtle and subjective reasoning concerning the sport perception. Such a fuzzy motivational assessment enables to stratify and score, by qualitatively and quantitatively measure, the impact in the adherence in the sports practice of recreational runners.

关键词： Training Fuzzy logic Input variables Current measurement Psychology Linguistics Cognition

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Multilevel Single-Phase Four-Leg AC-DC-AC Converter

Multilevel Single-Phase Four-Leg AC-DC-AC Converter

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IEEE Energy Conversion Congress and Exposition

作者： Phelipe L. S. Rodrigues Cursino B. Jacobina Antonio M. N. Lima Post-Graduate Program in Electrical Engineering - PPgEE – COPELE Federal University of Campina Grande (UFCG) Paraíba Brazil Federal University of Campina Grande (UFCG) Paraíba Brazil

ISBN: (数字)9781728158266

ISBN: (纸本)9781728158273

This paper presents a single-phase four-leg ac-dc-ac converter, with one leg shared by the grid side and the load side. The proposed topology can generate input and output voltages with seven levels, presenting reduced harmonic distortion, in addition to using reduced voltage switches. The space-vector pulsewidth modulation strategy (SV-PWM), the control technique, the system model, and a comparison with a three-leg topology will be presented. As for performance comparison parameters, harmonic distortion in currents and voltages, the average switching frequency, and semiconductor losses will be used. The topology was simulated and assembled in the laboratory to obtain experimental results.

关键词： Topology Legged locomotion Switching frequency Mathematical model Switches Pulse width modulation Load modeling

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