EUREKA: Physics and Engineering最新文献

{"title":"Effect of particle size on ignition and oxidation of single aluminum: molecular dynamics study","authors":"Mahros Darsin, B. Fachri, Haidzar Nurdiansyah","doi":"10.21303/2461-4262.2023.002653","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002653","url":null,"abstract":"Alumina nanoparticle is one of the attractive nanoparticles synthesized by the plasma method. The oxidation step in this method is challenging to explain experimentally. This work was to perform a molecular dynamics simulation to determine the oxidation mechanism of aluminum nanoparticles with different sizes and oxidation levels in the oxide layer. This work was to perform a molecular dynamics simulation to determine the oxidation mechanism of aluminum nanoparticles with different sizes and oxidation levels in the oxide layer. The simulation method employed the ReaxFF potential. The material used is aluminum nanoparticles in three different sizes (8, 12, and 16 nm) with an oxide layer thickness of 0.5 nm. Aluminum nanoparticles were given a relaxation treatment of 300 K for 1 ps and then heated to a temperature of 3250 K with a heating rate of 5×1013 K/s and cooled to 300 K. The ensemble used is a canonical ensemble with the Nose/Hoover thermostat method. The result shows that the higher the temperature applied to the system, the more oxygen molecules adsorption occurs on the surface of the oxide layer and the diffusion of oxygen to the particle core. The higher temperature applied also causes gaps, or void spaces, between the core and the shell. The reaction barrier for diffusion of oxygen also decreased significantly due to void space, and the surface of the aluminum core dissociates to the surface (alumina shell). Particles with a smaller size have a shorter ignition delay time. In addition, the smaller the particle size, the more oxygen molecules' reacted with aluminum particles in the particle core","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81104247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research to determine the best value of both Z and OVC in micro-EDM using carbon coated electrode using topsis method","authors":"D. V. Pham","doi":"10.21303/2461-4262.2023.002790","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002790","url":null,"abstract":"In the machining process, it is difficult to solve problems due to the relationship between productivity and quality, for example, as the productivity increases, the quality of reprocessing may decrease. Some methods only address specific objectives, such as the quality of the machining method, the machining productivity, the quality, or even the cost. Electrical discharge machining (EDM) and micro-EDM are most commonly used for processing the surfaces of die and moulds. The amount of electrode wear in micro-EDM has a direct effect on the dimensional accuracy of the machined hole. Therefore, improving the corrosion resistance of electrodes in micro-EDM is still of great interest. The effective coating of thin film for the micro tool electrodes in the case of micro – EDM can lead to minimize the electrode wear which eventually improve the productivity and machining quality. In the present study, experiments were performed on micro – EDM using carbon coated tool electrode and optimized using Taguchi-Topsis to investigate optimum levels of Depth of cut (Z) and overcut (OVC). It was concluded that optimum conditions had improved significantly using carbon coated micro tool electrode. Optimal  levels of technological parameters include V=160 V, C=10000 pF, RPM=400 rpm, and Zopt=2,525 mm, OVCopt=72,856 μmm. The quality of the machined surface with the coated electrode at optimal conditions is analyzed and evaluated. The Topsis method is a suitable solution to this problem, and the steps to perform the calculation in this technique are simple","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"76 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77387149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Smart automated fish feeding based on IoT system using LoRa TTGO SX1276 and cayenne platform","authors":"A. O. Silalahi, A. Sinambela, Hans Mawito Panggabean, Jekson T. N. Pardosi","doi":"10.21303/2461-4262.2023.002745","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002745","url":null,"abstract":"One type of aquaculture that is commonly found in Indonesia is freshwater fisheries in the form of densely stocked fish ponds. An important factor that supports the success of this aquaculture is an appropriate and scheduled feeding system the fish. To address this problem, this paper proposed a smart automation system was designed and implemented to perform feeding management with solar panel as the power. To enhance the productivity of the fish, this paper proposing a new contribution based on Internet of Things (IoT) solution that could control and monitoring the schedule time and amount of feeding and the food behavior of fish. This system is accessed through the Cayenne website and using LoRa TTGO SX1276 to microcontroller and it showed that the schedule and amount of feed was successful with a high accuracy and the panel system also worked well in monitoring and controlling the power system. From the results of testing the entire system, it can be concluded that the feeding automation system can help optimize the productivity of freshwater aquaculture, and provides an innovative solution which user-friendly, secure, scalable, low cost and go green, reliable","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"600 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76446626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing an image’s compression while keeping quality standards utilizing new mathematical technology","authors":"A. Abdulrahman, J. A. Eleiwy, Ibtehal Shakir Mahmoud, Hassan Mohamed Muhi-Aldeen, F. S. Tahir, Y. Khlaponin","doi":"10.21303/2461-4262.2023.002903","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002903","url":null,"abstract":"The rapid development of technology led to the need to keep pace with it, especially in the field of image processing, because of its importance in the need to get better results. In this paper, new discrete Chebyshev wavelet transforms (DChWT) derived from Chebyshev polynomials (ChP) were proposed and characterized. In terms of orthogonality and approximation (convergence) in the field of mathematics, (ChP) were qualified to transform into discrete wavelets called (DChWT), depending on the mother function with operators (s, r), and were used in image processing to analyze them in the low filter and the high filter so that the image is analyzed into coefficients. Proximity and detail coefficients, which lead to dividing the image into four parts, low left (LL), in which the proximity coefficients are concentrated while the rest of the parts are centered on the detail coefficients, which are high left (HL), low right (LR), and high right (HR), and image compression through the new filter, which has proven its efficiency at level (8) in our results. The results of the proposed wavelets in this work were reached in calculating quality standards in the image obtained after the compression process after comparing them with the results obtained using the standard wavelet used in HaarSymlet 2, Conflict 2, and Daubecheis 2. The most important of these standards is a mean square error (MSE), peak signal-to-noise ratio (PSNR), bit per pixel (BPP), compression ratio (CR), and table one. In this paper, the efficiency of the proposed new wavelets is explained after adding it to MATLAB and according to a specific program to drop in with the basic wavelets to take on their role in important tasks in the image processing area, like artificial intelligence","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"61 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84480578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of fishing boat collision models in extreme weather using computer simulation","authors":"Sunardi, Moch. Agus Choiron, Sugiarto, P. Setyarini","doi":"10.21303/2461-4262.2023.002601","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002601","url":null,"abstract":"The incidence of fishing boat accidents in Indonesia is very worrying, with 342 people dying during 2018–2020. Based on this, it is crucial to investigate the construction strength of fishing vessels against the possibility of a collision. In this study, the fishing boat due to the impact load was investigated in extreme weather conditions using Finite Element Method (FEM) analysis. Traditional fishing boat was constructed by measuring the thickness of the hull, deck, keel, frames, and longitudinal structure of the fishing boat. The collision model is carried out with an impactor in the form of a mooring pole during extreme weather with a wave height of 6 meters and wind speeds 30 knots. Variations in velocity and frame spacing as in actual conditions are modeled to obtain differences in deformation, absorption energy values, and plasticity of boat construction due to collisions. The collision speed of 30 and 20 knots are set on the extreme weather conditions, while the collision speed of 7 knots is set on operating speed. Frame spacing of 0.5 and 0.6 meters is built according to the boat's frame spacing in the field. Computer simulation is carried out using application software ANSYS Research License. The fishing boat material used is mahogany wood with tested by using impact test with a toughness value of 39.1 kJ/m2. Based on the simulations results, the impact velocity has an effect deformation wider crash area and hull stress value. The speed of the ship collision was 7 knots, the collision did not damage the hull, but the construction failed at speeds of 20 and 30 knots. The closer of frame spacing, the higher collision performance of structure to withstand impact are indicated by the higher energy absorption. At a ship collision speed of 30 knots, the absorption energy of the construction at 0.5-meter frame spacing is 49.8 kJ, greater than 0.6-meter frame spacing with a value of 29.6 kJ","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"112 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85138072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Choosing the best machine tool in mechanical manufacturing","authors":"N. H. Son, T. Hieu, N. M. Thang, H. N. Tan, Nguyen Tien Can, Pham Thi Thao, Nguyen Chi Bao","doi":"10.21303/2461-4262.2023.002771","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002771","url":null,"abstract":"Machine tools are indispensable components and play an important role in mechanical manufacturing. The equipment of machine tools has a huge effect on the operational efficiency of businesses. Each machine tool type is described by many different criteria, such as cost, technological capabilities, accuracy, energy consumption, convenience in operation, safety for workers, working noise, etc. If the selection of machine is only based on one or several criteria, it will be really easy to make mistakes, which means it is not possible to choose the real best machine. A machine is considered to be the best only when it is chosen based on all of its criteria. This work is called multi-criteria decision-making (MCDM). In this study, the selection of machine tools has been done using two different multi-criteria decision-making methods, including the FUCA method (Faire Un Choix Adéquat) and the CURLI method (Collaborative Unbiased Rank List Intergration). These are two methods with very different characteristics. When using the FUCA method, it is necessary to normalize the data and determine the weights for the criteria. Meanwhile, if using the CURLI method, these two things are not necessary. The selection of these two distinct methods is intended to produce the most generalizable conclusions. Three types of machine tool, which are considered in this study, include grinding machine, drilling machine and milling machine. The number of grinders that were offered for selection was twelve, the number of drills that were surveyed in this study was thirteen, while nine were the number of milling machines that were given for selection. The objective of this study is to determine the best solution in each type of machine. The results of ranking the machines are very similar when using the two mentioned methods. Specially, in all the surveyed cases, the two methods FUCA and CURLI always find the same best alternative. Accordingly, it is possible to firmly come to a conclusion that the FUCA method and the CURLI method are equally effective in machine tool selection. In addition, this study has determined the best three machines corresponding to the three different machine types","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"101 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80388098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combination of symmetry point of criterion, compromise ranking of alternatives from distance to ideal solution and collaborative unbiased rank list integration methods for woodworking machinery selection for small business in Vietnam","authors":"Tran Van Dua","doi":"10.21303/2461-4262.2023.002763","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002763","url":null,"abstract":"Woodworking industry plays an important role in the development of Vietnam’s economy. The efficiency of woodworking process depends a lot on the machinery used in the woodworking process. Selecting the best option among a variety of machines is tedious and complex work. However, if the choice of machine is based only on the subjective opinion of the customer, it will lead to mistakes. That mistake is understood that the customer will choose the option that is not the best among the machines proposed by the supplier. Instead, machine selection must be based on all machine parameters. This is called multi-criteria decision making (MCDM). There are MCDM methods, when used it is necessary to know the weights of the criteria. However, there are also methods that do not need to know the weights of the criteria. CRADIS (Compromise Ranking of Alternatives from Distance to Ideal Solution) is a method that, when used, is required to weight the criteria. In contrast, this problem is unnecessary when using the CURLI (Collaborative Unbiased Rank List Integration) method. In this study, three kinds of machinery commonly used for small business in woodworking field were selected. The three kinds of machinery mentioned in this study include wood milling machine, wood saw machine, wood planer. The SPC (Symmetry Point of Criterion) method was used to calculate the weights of the criteria for each kind of machinery. This is the youngest method among the methods of determining the weights for the criteria, it was only found in 2023. The two methods include CRADIS and CURLI were used to rank the machinery kinds. The result showed that in all the surveyed situation, the best alternative is always determined consistently when using CRADIS and CURLI methods. Accordingly, three best alternatives with three different machinery kinds (milling machine, saw machine and planer) were found in this study","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"2015 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87808464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact elements of feed grinder: a review","authors":"R. Iskakov, S. Issenov, Gulmira Kubentaeva","doi":"10.21303/2461-4262.2023.002820","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002820","url":null,"abstract":"The article deals with the issue concerning the working bodies of technological equipment designed for grinding pieces and particles of feed raw materials. The most profiTable feed raw materials are by-products and waste materials of animal origin, which have a valuable high-protein content. An alternative way of mandatory waste disposal is their processing, including mechanical grinding to obtain feed products. In the process of grinding, particular importance is given to the working bodies, with the help of which the raw material is directly divided into parts. In this case, the destruction of the feed material often occurs by means of impact. Impact phenomena have proven to be highly effective in the process of intense cracking and chipping, which leads to the desired separation of the crushed particles into smaller ones. However, it is found that crushers have insufficient efficiency of impact elements. The work analyzes the processes of impact grinding from the standpoint of a number of scientific hypotheses, theories, modeling, simulation, experience and approbation, presented in various scientific publications. When studying and improving the theory of impact, attention is paid to nonlinear problems, cracking, modernization of the theory of brittle fracture, diagrams of force changes during impact force, impact equations, wave theory of impact, peridynamic theory. It should be noted that the main scientific results are directly reflected in the improvement of the design features of hammers. It has been revealed that the main improvement in the design of impact elements is in the direction of increasing the efficiency of working surfaces and developing the combination of impact with cutting, abrasion and crushing","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73698918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical comparison and efficiency analysis of three vertical axis turbine of H-Darrieus type","authors":"Angie Guevara-Munoz, D. Hincapie-Zuluaga, J. Sierra-Del Rio, M. A. Rodriguez-Cabal, E. Torres-López","doi":"10.21303/2461-4262.2023.002593","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002593","url":null,"abstract":"Hydropower is an important source of energy in Latin America. Many countries in the region, including Brazil, Peru, Colombia, and Chile, rely heavily on hydropower plants to meet their energy needs. However, there are also challenges related to the use of hydropower in the region, such as the construction of dams that can have negative impacts on ecosystems and local communities. A new alternative is the production of energy through hydrokinetic turbines because they are a clean and renewable energy source that does not emit greenhouse gases. In addition, its production is predictable and can be generated in a variety of environments, from coasts to rivers and canals. Within the hydrokinetic turbines are the H-Darrieus turbines although they are still under development, they are seen as an important opportunity to diversify the energy matrix and reduce dependence on fossil fuels. The main purpose of this study is to determine and compare the efficiency of three Darrieus H-type vertical axis hydrokinetic turbines numerically. The turbines were configured with different solidities. The NACA 0018 profile was used for the turbine design. The study was carried out using the ANSYS® Fluent 2022R2 software, two-dimensional (2D) simulations set up constant operating conditions. Rotation speed variations have been set between 21 and 74 RPM with 10 rpm increments. Furthermore, the General Richardson extrapolation method is used for the analysis of mesh convergence, monitoring the turbine power coefficient as a convergence parameter. The numerical results show that the turbine H-Darrieus with a solidity of 1.0, a wider operating range, and lower power and torque coefficient. At low TRS, the largest solidity provided the best efficiency and the greatest self-starting capability, but it also had the smallest operating range","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"75 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90146890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A simple sinusoidal quadrature oscillator using a single active element","authors":"Suphaphorn Panikhom, A. Suksawad, Thitiporn Janda, A. Jantakun","doi":"10.21303/2461-4262.2023.002688","DOIUrl":"https://doi.org/10.21303/2461-4262.2023.002688","url":null,"abstract":"This study describes a simple design for a single active element sinusoidal oscillator with a quadrature signal. A current conveyor transconductance amplifier (CCTA), a single resistor, and two grounded capacitors are used in the first circuit. The second circuit is improved by using a current-controlled current conveyor transconductance amplifier (CCCCTA) and two grounded capacitors without a passive resistor, which means the grounded capacitor is suitably implemented for the IC fabrication. The oscillation condition and frequency of both circuits can be controlled using the same method that concurrently adjusts the DC bias current and the resistance as well as the oscillation frequency can be independently adjusted by capacitances. The CCTA is achieved by cascading the integrated circuits (IC) AD844 and LM13700, made by Analog Devices Corporation and Texas Instruments, respectively, which are available for commercial purchase. The sinusoidal quadrature signals in the time-domain and frequency-domain can be shown with computer simulations and the results of experiments. The Monte Carlo Analysis is also utilized to examine the oscillation frequency with the influence of passive element tolerance errors. The predicted oscillation frequency has a standard variation of about 20.04 kHz, with a maximum frequency of approximately 346.89 kHz and a minimum frequency of approximately 259.09 kHz. In addition, the mean and median frequencies are 296.10 and 293.98 kHz, respectively. The results of this study indicate that computer simulation and experiment are similar to a theoretical analysis, making them suiTable for use in the teaching of electrical and electronic engineering","PeriodicalId":11804,"journal":{"name":"EUREKA: Physics and Engineering","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83610577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}