bluuebunny/crossref_metadata_2025 huggingface dataset:
Derivation of Met-Ocean Conditions for the Simulation of Floating Wind Turbines: a European case study
Authors: Papi F. , Perignon Y. , Bianchini A.
Published: December 2022

Offshore wind turbines are subject not only to varying wind conditions during their lifetime, but also sea conditions. Therefore, in addition to wind speed, other sea-related quantities need to be considered to characterize a specific installation site. International standards suggest that, at a minimum, significant wave height, peak spectral period and wind/wave misalignment must be considered. In order to have a statistically significant description of the potential installation site, the long-term distributions of the three environmental variables must be determined. In this context, the objectives of the present work are twofold: firstly, to demonstrate the procedure trough which environmental conditions including wind and wave information can be derived using open-source tools. Secondly, an exemplary dataset is provided. The dataset is used both do demonstrate the procedure and provided as a ready-made example for use in future studies. The provided dataset is used in the EU-funded Horizon 2020 project FLOATECH.
PV-based hybrid residential microgrid with hydrogen and battery energy storage options: a Northern Italy case study
Authors: Damato A , Iamarino M. , Ferraro A , D’Angola A
Published: December 2022

Residential microgrids based on renewable energy sources (RES) are promising solutions for the ongoing energy transition but, at the same time, must also cope with the intermittency of the energy source and the limited energy storage capacity. To overcome such problems, RES-based microgrids usually rely on backup powering systems, such as a stable connection to the main grid or the presence of emergency electricity generators. In order to significantly increase the autonomy of the microgrid and limit the presence of backup solutions, an additional energy storage system based on hydrogen is proposed here, which complements the more classical option of energy storage in batteries. The microgrid under investigation is composed by a PV system, a lithium-ion battery for short term energy storage, and a hydrogen-based storage system composed of a PEM electrolyzer, a pressurized hydrogen tank and a low temperature PEM fuel cell stack. The system is managed by a control system which balances at each time the energy demand with the energy produced from different sources. Results reflect the role of hydrogen as efficient long-term storage option, while the battery fulfills short-terms storage needs. With properly sized components, the microgrid turns out to be fully autonomous during one year and can therefore work also in off-grid mode. The impact of an improved energy management approach is also highlighted, which may lead to increased hydrogen production and higher level of autonomy of the microgrid.
Application of an overset grid method for the performance analysis of flapping airfoils
Authors: Lemmi G. , Giaccherini S. , Marconcini M. , Pinelli L.
Published: December 2022

With the growing importance of renewable energy, the interest in energy-harvesting technologies based on flow-induced vibrations of airfoils has been rekindled in the past few years. Compared to conventional turbines, these devices are centrifugal stress-free and hence they are structurally more robust. They are also environmentally friendly due to the relatively low speeds, thus reducing the impact on flying animals. In order to numerically investigate these types of devices, mesh motion techniques must be used so that the computational grid can adapt to the time-varying shape of the domain and boundaries, thus preserving its robustness and quality. During the last years, many different dynamic mesh approaches have been developed to better predict the behaviour of a flow interacting with solid moving bodies. The aim of the present work is to apply and validate the overset grid method offered by the OpenFOAM software. In this type of mesh, one or more grid blocks are allowed to overlap with other sets of cells to solve the fluid domain with moving bodies, thus showing many potential advantages compared to the other existing dynamic mesh approaches. In the first part of this work, a numerical investigation of the flow over a stationary SD 7003 airfoil at low Reynolds number has been performed using an unsteady RANS approach. The computed results have then been compared to experimental and high-fidelity computational data available from the literature in order to validate the presented model in terms of numerical domain configuration, mesh refinement, and turbulence modelling. Subsequently, unsteady RANS simulations have been performed on the SD 7003 and NACA 0012 airfoils for two different amplitudes of flapping motion, i.e., 30° and 45°. Finally, the results obtained with the OpenFOAM overset grid solver have been compared with the numerical and experimental benchmarks presented by Kurtulus, showing an excellent agreement with both computed and measured data.
Experimental and numerical investigation of a micro-ORC system for heat recovery from data centers
Authors: Ancona M A , Bianchi M , Branchini L , Pascale A De , Melino F , Ottaviano S , Peretto A , Poletto C
Published: December 2022

In the effort to enhance the recovery of waste energy, data centers are drawing attention because of the huge amount of heat discharged from the computer racks. Organic Rankine cycle (ORC) power systems are a viable solution to exploit servers’ waste heat, as it is available at very low temperatures. The purpose of this study is to assess the feasibility of integrating a micro-ORC system into data centers cooling systems and its potential energy saving. An experimental analysis is carried out on a kW-scale ORC test bench, with R134a as working fluid. Heat is supplied at temperatures and flow rates in the range respectively 40-55 °C and 1.8-5 m3/h, consistently with typical values observed in data centers application, showing the second law efficiency varying between 5% and 13%. Furthermore, a steady-state model of the micro-ORC has been recalibrated and validated against experimental data; the built-in volume ratio of the reciprocating piston expander has been optimized to improve the filling performance of the machine. A parametric analysis, varying the boundary conditions within their range of interest for this application, and the working fluid (R1234yf and R1234ze(E)), shows that a maximum second law efficiency of 30% is achievable with R1234ze(E).
Exergo-economic and exergo-environmental analysis of a binary geothermal power plant with solar boosting
Authors: Giusti E. , Ciappi L. , Ungar P. , Zuffi C. , Fiaschi D. , Manfrida G. , Talluri L.
Published: December 2022

The exploitation of renewable energies is a solution to the energy, economic and environmental issues related to the massive use of fossil resources. Thus, investing in renewable technologies is essential to achieve the carbon-neutral scenario within 2050. In this framework, geothermal energy may have a key role. In particular, power plants with a closed binary cycle are suitable for harnessing geothermal resources with low and medium enthalpy levels. They are prone to be integrated with other renewable devices to increase the global power output.

Geothermal fluid can be drawn constantly from underground throughout the day and seasons. Conversely, the availability and intensity of solar energy depend on weather conditions and the time of year. In Italy, geothermal energy is currently harvested for continuous electricity generation, while solar energy is mainly used for photovoltaic generation. For small-to-medium size plants, rated between 5 and 20 MWe, the geothermal and thermodynamic solar hybridization may lead to relevant benefits for the economic competitiveness regarding separate photovoltaic or thermodynamic solar systems.

This article aims to investigate the economic and environmental aspects of geothermal power plants with a closed binary cycle coupled with a topper cycle fed by linear parabolic solar collectors. The system operation in both design and off-design conditions was analysed, and exergo-economic and exergo-environmental simulations were conducted. The application site was selected near Torre Alfina (Italy). It has a water-dominant reservoir with a pressure of 44 bar, a temperature of 140 °C, and content of non-condensable gases (NCGs) approximately equal to 2% by weight. At the design point, the net power is 8.4 MW and the first and second principle efficiencies are 9.31% and 18.45%, respectively. The exergo-economic and exergo-environmental analyses indicate that the components with the highest economic and environmental impact are the condenser, the field of solar collectors, the evaporator, and the low-pressure turbine. The levelized cost of electricity (LCOE) is equal to 14.19 c€/kWh.
Re-designing district heating networks through innovative CO2 solutions
Authors: Ungar P , Milli L , Manfrida G , Fiaschi D , Talluri L
Published: December 2022

One of the main problems of current district heating networks is the significant heat losses that occur due to the high temperature of the heat distribution fluid (usually, water in the Italian climate conditions). Moreover, in ORC- or steam-turbine-based cogeneration power plants, the heat distribution fluid is heated directly by the condenser of the ORC cycle resulting in low efficiency of the power production section of the system. Considerable power is also employed for pumping the district heating flow rate through a long distribution ring. In this work, the effect of replacing water with low-temperature CO2 as a working fluid in a district heating network is analyzed. Specifically, a real district heating installation (the Biogenera-Calenzano network) providing at design conditions 850 kW of electricity and 1.7 MW (average) of heat is assessed using an experimental data set, simulating the equivalent working conditions with CO2 distributed through the network.

The proposed innovative solution continues to receive the heat from the condenser of an ORC cycle, but the temperature of the working fluid is significantly lower providing a relevant increase in the power production because of the reduction of the condenser temperature (determining an increase of the expansion ratio of the turbine). The increased power production of the turbine exceeds the power needed by local heat pumps which should be installed near the utilities of the district heating network to provide flexible heat on demand.
How to extrapolate 3D aerodynamic coefficients from HAWT CFD simulations: an inverse BEM approach
Authors: Mauro Stefano , Lanzafame Rosario , Messina Michele , Brusca Sebastian
Published: December 2022

In the present work the authors developed a methodology based on an inverse BEM method, to easily extrapolate 3D aerodynamic coefficients from HAWT CFD 3D simulation results. Specifically, since the BEM method was based on the solution of a discrete number of blade radial sections, the CFD model was implemented in Ansys Fluent in such a way to split the surface of one of the blades in a certain number of sections already at the CAD level. Therefore, the normal and tangential aerodynamic forces were calculated for each radial section and subsequently provided directly within the modified BEM code developed in Matlab. Thus, the BEM code iterated for the axial and tangential induction factors and calculated the lift and drag coefficients, the related local angle of attack, the torque, the power and the power coefficient for each specific operating condition simulated. The methodology proposed here was validated using the NREL Phase VI rotor geometry for which a very good agreement between numerical and experimental data was found. Furthermore, this allowed for an insight into the 3D effects over the blade since it was possible to compare the experimental 2D and the 3D lift and drag coefficients section by section.
Sustainable opportunities to recover power plants’ waste heat: a benchmark of techno-economically optimized heat pumps
Authors: Grisolia T , Vannoni A , Sorce A , Calabria M
Published: December 2022

Current climate targets, adopted worldwide, pursue the decarbonization of all energy sectors. In power generation, the spread of RES has caused the shift of the Combined Cycle Gas Turbine (CCGT) power plants’ traditional role from providing constant baseload power to flexible operations providing services and backup capacity to the grid, as a consequence, the revenues opportunities on the traditional electricity markets (e.g., day-ahead, and intra-day markets) are no longer certain. At the same time is urgent to address a significant carbon intensity reduction in the heating sector, which is responsible for a large part of the current greenhouse gas emissions. Exploiting the low-exergy waste heat of CCGT’s water-cooled condenser as a thermal source for vapor compression heat pumps can meet two targets. On one hand, the revenues from heat production enhance the viability of the CCGT power plant, often essential for the security of the electrical supply. On the other hand, the heat delivered to the user represents a low-carbon alternative to traditional gas-fired boilers or even to air-sourced heat pumps characterized by lower efficiency. This work assesses the recovery of thermal energy from the sea cooling water at the bottoming cycle condenser of Tirreno Power 794 MWel CCGT in Vado Ligure through a high-temperature heat pump using R600 as a working fluid. Cooling water represents a privileged heat source and the integration into the power plant’s site allows running the HP at a lower cost than the electricity retail price. The case study takes into account the new Vado Ligure sports hall, to size the HP and explore the economic and environmental performances. The proposed layout is compared with the main solutions available: air source heat pump, gas, and electric boilers. The results show that on a lifespan of 20 years such integration of a heat pump with a CCGT could lead to consistent economical savings and emissions cuts.
Influence of the trigger time window on the detection of gas turbine trip
Authors: Losi E , Venturini M , Manservigi L , Bechini G
Published: December 2022

Gas turbine (GT) trip is one of the most disrupting events that affect GT operation, since its occurrence causes a reduction of equipment remaining useful life as well as revenue loss because of business interruption. Thus, early detection of incipient symptoms of GT trip is crucial to ensure efficient operation and lower operation and maintenance costs. This paper applies a data-driven methodology that employs a Long Short-Term Memory (LSTM) neural network and a clustering technique to identify the time point at which trip symptoms are triggered. The same methodology also partitions trips into homogeneous clusters according to their most likely trigger position. The methodology is applied to two real-world case studies composed of a collection of trips, of which the causes are different, taken from various fleets of industrial GTs. Data collected from twenty sensors during three days of operation before trip occurrence are analyzed. For each trigger scenario, this paper investigates different lengths of the training and testing time window (namely “trigger time window”), by considering up to 24, 18, 12 or 6 hours before and after the considered trigger position. The results demonstrate that longer time windows allow an improvement of the predictive capability.
Wells turbine efficiency improvements: experimental application of a speed control strategy
Authors: Licheri Fabio , Ghisu Tiziano , Cambuli Francesco , Puddu Pierpaolo
Published: December 2022

Systems based on the OWC principle allow to convert the sea-wave energy into electrical energy. The potential energy contained in the wave motion is first converted into the pneumatic energy of a bi-directional airflow, generated by the oscillatory displacement of a column of water inside a chamber. Then, an air turbine, such as the Wells turbine, placed at the top of the chamber, converts the pneumatic energy into mechanical energy at its shaft, which can be coupled to an electric motor to produce energy. The turbine’s performance is strongly affected by the non-stationary behavior of the airflow, which continuously changes its intensity. Control solutions based on the variation of the turbine rotational speed can overcome this limitation.

This work aims to study a speed-controlled Wells turbine with an experimental approach, making use of a turbine coupled to an Oscillating Water Column (OWC) simulator. A control law for the rotational speed has been defined and applied to the turbine in order to move the turbine’s operating conditions as close as possible to its maximum efficiency point, for the majority of the piston period.

The experimental results prove the effectiveness of the proposed control strategy for moving the operating conditions and for obtaining operating conditions close to the best efficiency point for the majority of the wave period.
Analysis of satellite-derived data for the study of fouling in aircraft engines
Authors: Zanini Nicola , Suman Alessio , Friso Riccardo , Pinelli Michele
Published: December 2022

Atmospheric particulate is one of the main causes of performance degradation in gas turbine engines, especially in the aeronautical field where filter barriers are absent. The ingested particles can stick to the blade surfaces of the engine, varying their shape and roughness. As a consequence, engine performance degradation takes place. The type and the amount of the particles ingested depend on the flight zones and altitude. During their missions, aircrafts follow a prescribed path defined in terms of altitude, longitude, and latitude. During its route, the aircraft engine encounters different environments characterized by different temperature, pressure, and air composition. Regarding the latter issue, the knowledge of this characteristic can be key information when these statistics are needed for obtaining data useful for engine degradation assessment or prediction. Many satellites, such as the environmental satellite CALIPSO, are employed to study the terrestrial aerosol and clouds profile by using a LIDAR (Laser Detection and Ranging). This technology is commonly used to determine the distance between a light emitter and an object and it is based on the light refraction phenomenon. Backscatter coefficients profiles data, which characterize the distribution of particles and aerosols in the atmosphere, are available in the open literature from the findings of CALIPSO. In this work, a new methodology to estimate the aerosol type and concentration encountered by an aircraft during a mission is proposed. To test the feasibility of this method, two aircraft missions for different length scales (medium and long haul) are analyzed and an estimate of the particulate encountered by the engines is provided. The mission analysis has been conducted by discretizing the altitude profile, longitude, and latitude coordinates of each flight and then cross-referencing them with the particulate concentration obtained from CALIPSO data.
A Study on Accounting for Drift Velocities on Liquid Jets Injected in Cross Flow
Authors: Sahranavardfard Nasrin , Pandal Adrian , Rahantamialisoa Faniry Nadia Zazaravaka , Battistoni Michele
Published: December 2022

The efficiency and combustion performance of propulsion systems, like internal combustion (IC) engines and gas turbines, is known to be related to the performance of the fuel and air mixing process. Operating conditions and fuels are rapidly changing, therefore new CFD models which accurately accounts for all physical aspects, still maintaining a simple framework, are extremely important. In this work we consider the drift velocity contribution, which often is overlooked or neglected, defined as the velocity of the dispersed phase relative to the mixture volumetric mean velocity in a single fluid formulation, a key variable in two-phase mixture model. Water test cases are here considered for the study. The present work investigates the structure and the droplet velocity field of a plain liquid jet injected into a high-pressure air crossflow. Because of the large scale separation between the small features of the interface and the overall jet we use the diffuse-interface treatment in a single-fluid Eulerian framework. A Σ- Y family model is implemented in the OpenFOAM framework which includes liquid diffusion due to drift-flux velocities and a new formulation of the spray atomization. The main objective is to explore the droplet velocity distribution and the jet structure with and without considering the drift flux correction and compare the related results with the experimental data.
Towards a low-noise axial fan for automotive applications
Authors: Casari Nicola , Oliani Stefano , Pinelli Michele , Piovan Mattia , Paola Elisa de , Stoica Luana G. , Marco Alessandro Di , Mollica Enrico
Published: December 2022

The demand for quieter vehicles is pushing manufacturers of components for the automotive industry to seek for solutions to reduce the overall noise emissions. The cooling fan makes no exception: the aerodynamic interaction of the blades with the incoming flow generates turbulence and pressure fluctuations which ultimately translate into noise generation. A variety of expedients have been introduced to limit the produced noise, but no univocal solution has been found.

In modern research, Computational Fluid Dynamics (CFD) has been successfully applied to blades and fans for both the flow and acoustic field derivation. By including the acoustic field, researchers have been able to predict the effect of changes in the blade geometry on the overall sound emission. This work reports a conjugate numerical-experimental study of a reference profile in different flow conditions, in order to validate the CFD acoustic prediction and to lay the basis for improved candidates able to lower the fan-generated noise.
Robust Proportional-Derivative Control on SO(3) for Quadrotor under Inertia Perturbation
Authors: Setiawan N , Hidayatullah I R , Pratama G N P
Published: December 2022

The presence of inertia perturbation should not be ignored, it may harm the stability of quadrotor. There are many causes, one of them is due to the payload attached to the quadrotor. Here, the inertia perturbation comes from the payload that subject to the laying position and the mass. Although unknown, the mass and position of payload are limited to certain value. In this paper, we provide the robust Proportional-Derivative (PD) control of a quadrotor while considering the inertia perturbation. The control law is designed by generating torques in SO(3) group which will regulate the angles and the angular velocity to reach the equilibrium points. In the same time, the inertia perturbation is countered by a proposed compensator. The effectiveness of the control law is clarified by using numerical simulation. The results show that the control law prevails in stabilizing the quadrotor in both nominal condition and the condition under inertia perturbation. It is verified that the proposed control law can stabilize the quadrotor despite being under inertia perturbation.
A Vision and GPS Based System for Autonomous Precision Vertical Landing of UAV Quadcopter
Authors: Priambodo A S , Arifin F , Nasuha A , Muslikhin  , Winursito A
Published: December 2022

This research aims to develop an algorithm for the precision vertical landing process on a quadcopter using GPS sensors and computer vision. This research consists of 2 main parts: GPS-based control used by the quadcopter to return to the home area and computer vision-based control in the form of ArUco marker detection, which is used by the quadcopter in order to land precisely. Detection of the ArUco marker that is used goes through 2 stages: the application of threshold and ratio and the process of calculating the black and white area, which can then be searched for four corners of the marker. The algorithm designed works well on the Webots simulation program with mid-computer specifications. The ArUco marker detection process is fast and reliable, so it does not overload the processor unit so that the simulation process can run well. From 30 tests with different initial positions, the average error of the landing position of the quadcopter at coordinate X is 0.02 meters, and coordinates Y is 0.03 meters. All test results show that the quadcopter can land inside the landing pad area without any parts coming out.
Design of automatic water level control system using fuzzy logic
Authors: Khairudin M. , Hakim M. L. , Rahmawan O. A. , Alfiati W. N. , Widowati A , Prasetyo E.
Published: December 2022

With less rainwater that is absorbed into the ground, and the obstruction of water flow causes flooding. The floodgates on river dams are still using manual systems by utilizing human operators, in this case sometimes mistakes occur in decision making. The solution to this problem is to create an automatic sluice system, so that when the condition of the water discharge at the intake is excessive or insufficient, the sluice can open and close pursuant to the required automation of water flow. Measurement of water discharge using a water flow sensor, the results of the sensor readings will be forwarded to the actuator as a door actuator. In this study, the design of the floodgate control system on the dam was carried out through the fuzzy logic technique. The water level and flow sensor data are processed by fuzzy logic technique to control the opening of the floodgates and the condition of the weir. The benefit of this system is easy to monitor and control the floodgates on the weir, with proper control and supervision it will make the water flow evenly distributed, as well as provide early warning information to anticipate when river water overflows and has the potential to flood.
Design of Automatic Room Door Lock System Based on Face Recognition
Authors: Yatmono S , Nugraha AC , Khairudin M , Hakim ML , Pradityarahman Y , Mustaqim FA
Published: December 2022

Face recognition is a method for recognizing human faces using a camera. There are various applications of facial recognition technology, one of which is Face Unlock technology on smartphones which functions as a security feature to open smartphone access through the user’s face. In this study, the use of facial recognition technology is used to automatically open the door of the room according to the registered face. The research method used is the waterfall method which has 5 stages. The research stages consist of requirements analysis, design, implementation & unit testing, integration & system testing, and operation & maintenance. This study uses a Raspberry Pi 4 to perform an automation system. The face detection process is based on the YuNet detection model, as well as the face recognition process using the SFace facial recognition model.
The Experimental Investigation of Heating Rate Variant Method to Produce Power Output Generated by Thermoelectric Generator SP1848-SA
Authors: Atmoko N T , Riyadi T W B , Haikal  , Amarulloh  , Wijayanto H L
Published: December 2022

Thermoelectric Generators (TEG) are a type of energy conversion device that uses the Seebeck effect to directly transform heat energy into electrical energy. The source of heat that will be transformed using this technology is one of many elements that determine TEG performance. Through laboratory-scale experimental tests, this research will examine how the performance of TEG in producing electricity and the temperature distribution profile is affected by changing the heating rate. The hot surface of the TEG module is heated by the heating plate, which is thought of as a source of wasted heat produced by the internal combustion engine. There are three heating rates available: low heating rate (0.35 °C/min), middle heating rate (0.93 °C/min), and high heating rate (1.55 °C/min). To collect temperature data in this research using the Arduino microcontroller temperature data logger, temperature measurements were taken on the TEG module’s hot surface (Th), cold surface (Tc), and ambient temperature (Ta). Arduino data logger is used to measure the electrical output performance in the form of net power output (P) generated by the TEG. The outcomes demonstrate that the pace of heating on the hot surface of the TEG module will impact to the surface temperature differential and the efficiency of the TEG module in producing electricity. The efficiency of TEG in producing electricity in the form of an average net power output increases with an increased heating rate.
Re-design AC Power Failure Signal to Minimize False Signal of Emergency Shutdown System for Ethylene Plant
Authors: Ali M , Hermawan Y
Published: December 2022

Chandra Asri, the largest integrated petrochemical company in Indonesia, requires a reliable electrical system to ensure production. Electrical power was supplied by the grid from PT. PLN through a 150 kV system in parallel with captive generation. The electrical system uses the Emergency Shutdown System (ESD) to protect against various disturbances that can cause equipment damage and work accidents. ESD will only work if things happen according to a logic diagram that has been designed according to the needs. One time, there was a power outage due to the active ESD. This causes huge losses for the company. The results of the investigation showed that there were no disturbances to either the grid or the captive generator. It is suspected that there is a false signal that causes the ESD to activate from the DC charger signal. For this reason, efforts are needed to eliminate the possibility of this nuisance signal occurring in the future by redesigning the logic and signal source of AC power failure by considering the existing secondary selective electrical system. Modification of the ESD system is carried out in 5 stages, namely 1) fault analysis, 2) modification of logic diagram design, 3) system development, 4) testing, and 5) evaluation. The results of the redesign decided that modifications should be made to the ESD system and carried out on the next Turn Around Maintenance schedule because this modification requires an offline electrical system. The analysis and simulation results show that the ESD system is safe against similar disturbances. It is hoped that the redesign and modification of the ESD system can prevent signal interference in the AC Power Failure Signal.
Evaluation and Mitigation of Voltage and Current Unbalance at MSTP Undip Jepara
Authors: Denis  , Sinuraya E W , Soemantri M , Rafif I R
Published: December 2022

Marine Science Techno Park (MSTP) Diponegoro University is a central for the application of technology and research in the fisheries and marine sector under the auspices of Diponegoro University. After measuring the electrical power quality parameters, a voltage and current unbalance problem was found on each SDP and MDP at MSTP Undip Jepara Building. The final project is designed to mitigate current and voltage unbalance with a load equalization method in each phase using ETAP 12.6 software. According to the ANSI C84.1-1995 standard, the maximum current unbalance value is 5% and according to the IEEE 45-2002 standard, the maximum voltage unbalance value is 3%. The equalization results show that the load can decrease the value of current unbalance, voltage unbalance, and neutral current that already meets the standards. Based on the evaluation of existing conditions, the current unbalance value on the MDP decreased from 21.522% to 0.419%, the MDP bus voltage unbalance value decreased from 0.280% to 0.015%, and the neutral current decreased from 35.5 ampere to 1 ampere.
Development of Monitoring Device for Battery Charge/Discharge Control as Electrical Energy Storage in Mini-Generating Systems
Authors: Khairunnisa’  , Hartoyo  , Nursusanto U
Published: December 2022

The battery is one of the crucial elements in an electrical system. In electric vehicles, the batteries used are Li-Ion batteries. Most Li-Ion batteries are also reusable. In addition, waste Li-Ion batteries can be used as electrical energy storage devices, such as in mini-power generation systems. With the existence of several power plants that do not use fossil energy as a means of the production process, it will automatically reduce the impact of environmental pollution. This study uses electric vehicle batteries to be used as storage of electrical energy in a mini-generating system. In its implementation, a control monitoring tool is also made and developed to determine the charging and discharging of the battery. This monitoring system is useful for keeping the battery in great condition.
Machine Learning and Deep Learning for Maize Leaf Disease Classification: A Review
Authors: Setiawan W , Rochman E M S , Satoto B D , Rachmad A
Published: December 2022

Image classification of maize disease is an agriculture computer vision application. In general, the application of computer vision uses two methods: machine learning and deep learning. Implementations of machine learning classification cannot stand alone. It needs image processing techniques such as preprocessing, feature extraction, and segmentation. Usually, the features are selected manually. The classification uses k-nearest neighbor, naïve bayes, decision tree, random forest, and support vector machine. On the other side, deep learning is part of machine learning. It is a development of an artificial neural network that performs automatic feature extraction. Deep learning is capable of recognizing large data but requires high-speed computation. This article compare machine learning and deep learning for maize leaf disease classification. There are five research questions: how to get data, how machine learning and deep learning classify images, how the classification result compare both of them and the opportunities & challenges of research on maize leaf disease classification. The number of articles to review was 62, consisting of 18 articles using machine learning, 28 articles applying deep learning, and the rest are supporting articles.
Classification of Salt Quality based on Salt-Forming Composition using Random Forest
Authors: Rochman E M S , Rachmad A , Fatah D A , Setiawan W , Kustiyahningsih Y
Published: December 2022

Salt is part of the chemical that can be used and needed by humans in the field of consumption or industry. The formation of salt can be done in several ways, namely with seawater or lake water that is evaporated to produce salt crystals or through the process of mining rock salt. The results of the salt obtained will have a different composition depending on the process of formation, the difference in composition can affect the quality of the salt produced, so not all salt results are suitable for consumption. Generally, the salt quality classification process is still done manually, but this method takes a long time and is less effective. So, to overcome this problem, this research utilizes data mining science in classifying salt quality automatically using the Machine Learning algorithm, namely Random Forest. The data used in this study is a salt dataset with 7 attributes and 4 target classes totaling 349 data where the data is divided into training data and test data using k-fold cross validation with different k-fold values, namely 5-fold, 10-fold, and 20-fold. folds. The test results obtained indicate that the value of k = 10 has the best performance by achieving an AUC value of 96.1%, then for the classification accuracy is 87.7%, f1 score is 87.6%, precision is 87.7% and recall is 87.7%.
Analysis of Clusters Number Effect Based on K-Means Method for Tourist Attractions Segmentation
Authors: Jauhari A , Anamisa D R , Mufarroha F A
Published: December 2022

The current development of tourism potential can have an impact on the implementation of regional autonomy. Madura is an island located at the northern tip of East Java Province, which has tourist attractions spread over four regencies, namely Bangkalan, Sampang, Pamekasan, and Sumenep. However, there are still many attractions that tourists have not touched. Therefore, the Madurese government tries to develop the existing potential. However, the development of this potential has not been carried out evenly by the government. This is due to the lack of grouping of data on the number of tourists, making it difficult for the tourism office to analyze the dominant visitor effect based on the variables that become characteristics in mapping the entrance ticket to increase the potential of tourism objects in Madura. There are 21 tourist objects in Bangkalan. There are several influencing factors to mapping, such as: Gender, age, occupation, education, and marital status. In this study, the admission ticket mapping system applies the K-Means method by dividing tourist objects into three groups including, (C1) high cluster, (C2) medium set, and (C3) low cluster. K-Means functions to map objects by mapping the analysis of data mining applications that can increase the number of tourist visits that impact the introduction of tourist objects and improve the country’s foreign exchange through the development of facilities and infrastructure.
IoT Based Renewable Energy Practicum Kit Design to Support learning and research
Authors: Widiyanto N , Asnawi R
Published: December 2022

In the era of the industrial revolution 4.0, various industries are required to implement internet of things technology, one of which is in the energy industry, so that internet of things technology becomes knowledge that must be mastered by electrical engineering program students. The implementation of internet of things technology in education is the development of a renewable energy practicum kit design to support the learning of renewable energy power plant practices in small-scale field laboratories. The internet of things-based practicum device will make it easier for students or researchers to observe and analyze any changes in data due to changes in weather parameters or changes in load. This practicum kit can be used for the practice and research of Renewable Solar Power plant and Wind Power plant. The observable data are data on the generated side and the usage side. The generated side is in the form of parameters of weather and climate conditions such as light intensity and wind speed, electrical parameters such as current, voltage, power and energy while the usage side is in the form of parameters such as current, voltage, power, energy, power factor and frequency. With the practicum kit with Internet of Things technology, it is hoped that students or a researcher can prove practical results with existing theories quickly and easily.
Research on Lifting and Installation of 132kV Power Transformer
Authors: Zhang Yu-Lei , Du Jian-Wei , Liu Hong-Tao , Zhang Miao-Chen
Published: December 2022

In this paper, the installation process of a transformer in the distribution room of a large power plant in the Middle East is analyzed in detail. According to the special geographical and climatic conditions of the construction site, combined with the previous construction experience of the enterprise, we select reasonable lifting machinery, design the handling path and handling method, and improve the support structure. At the same time, the key elements of transformer installation are analyzed and introduced to provide a reference for subsequent similar construction.
Embedded Digital Tuning Radio Based on stm32
Authors: Hu Xiaohui , Jin Jing
Published: December 2022

With the development of science and technology, people’s demand for material culture is also increasing. The development of radio with good sound quality, easy portability, certain technological content, and moderate price can meet market demand well. The embedded digital tuning radio based on stm32 uses a 32-bit embedded chip with fast processing speed, convenient development, and high-cost performance. At the same time, it is combined with TDA audio decoding chip to achieve digital decoding, cooperates with the LM386 power amplifier module to achieve high-quality audio output, and displays the search frequency through the OLED LCD screen, with high display brightness and clear display effect. The whole work is very in line with the aesthetics of modern people and enhances the technological impression of products such as radios in people’s minds.
Design of a Drum Brake Turnover Machine
Authors: Tian Feng , Zhu Jinfeng , Zhang Zhenshe
Published: December 2022

In order to meet the demand of turning over brakes in an automatic assembly line of drum brakes, a drum brake turnover machine is designed. SolidWorks software is used to complete the three-dimensional modeling of the mechanical structure of the whole device; The control system of the drum brake turnover machine based on Schneider M241 PLC is designed, and the AC servo system control based on CANopen BUS is realized. The precise control of the position of reclaiming, overturning, discharging and turning angle of the drum brake is achieved. The engineering application results show that the equipment has a high degree of automation, stable operation, and good economy.
An accurate measuring method for the internal jaw stiffness of deformable silicon arms
Authors: Saren Qimuge , Zhang Zhijing , Zhu Dongsheng , Zhang Tingyu , Su Taiyu
Published: December 2022

The internal jaw stiffness of the silicon arm and its uniformity directly determine the geometric position of the clamped part, which in turn affects the geometric accuracy of the fusion target ball. The slight variation of the silicon arm jaw stiffness caused by machining errors is a crucial factor affecting the geometric accuracy of the micro-target. To accurately detect the variation of internal jaw stiffness caused by machining errors, this paper proposes a multi-point stiffness detection method combining micro-feed force application and high-precision image inspection. An experimental measurement device is also built to measure the jaw stiffness of the silicon arm sample. The proposed method, which can obtain the micro-deformation data of the internal jaws under small loads and accurately fit the stiffness, provides a new way to measure tiny, thin-walled, brittle cantilever beam structures.
Research on Motion Analysis and Simulation Technology of Double Ship Floating Installation of Large Structures
Authors: Liu Ming
Published: December 2022

The offshore platform is developing towards the trend of large-scale, complex and centralized. Compared with the single-ship floating installation, the double-ship floating installation can be applied to the installation of more complex and diversified offshore platforms and can improve the safety of installation. It is the development direction of large-scale offshore platform installation technology. In this paper, the motion analysis and simulation technology of double ship floating installation are deeply studied. Through momentum analysis, load model, and motion model establishment, the kinematics simulation is carried out under the South China Sea working condition, which provides basic kinematics data for double ship floating installation.
Design of Hollow Horn Based on Four-terminal Network Method
Authors: Zhao Hua , Jia Haili , Chang Jinxin , He Hailong , Cao Yanwen
Published: December 2022

When designing the horn of the ultrasonic transducer for rotary machining, the traditional analytical method cannot consider the complex assembly cross-section of the horn, resulting in a large final simulation error and design error. At the same time, when the design diameter of the transducer is too large, the size of the back mass obtained by the traditional analytical method is too thin. This paper combines the four terminal network method and the finite element method, selects the sandwich piezoelectric transducer, takes the ER spring chuck commonly used in rotary machining as an example, derives the transmission matrix corresponding to the geometric cross-section shape, and then uses the four-terminal network method and the traditional analytical method to design two sets of stepped ultrasonic transducers with the design frequency of 22 kHz for analysis and comparison. Finally, through the analysis, it is verified that the ultrasonic transducer designed by the four-terminal network method has a performance closer to the theoretical design.
Research on multi-module parallel current equalization technology for high-power phase shifting full-bridge converters
Authors: Zhao Jiawei , Yang Ziwei , Liu Shichao , Dong Yu , Yang Shuaifei , Li Yang , Wu Chunyu , Liu Yang
Published: December 2022

DC/DC converter parallel power systems are widely used in high-power applications. However, the hardware parameter differences and communication time differences between modules can cause problems for the parallel current equalization of multiple modules. This paper summarizes and analyzes several parallel current equalization methods based on phase-shifted full-bridge circuits for multiple modules. The working principles of these methods are analyzed, and their respective advantages and disadvantages are given. Meanwhile, based on the traditional three-loop current equalization method, an improved three-loop current equalization control method is proposed, which improves the dynamic response of the system and ensures the operation efficiency of the power supply and the precision of current equalization between modules. The effectiveness of the improved method is also verified by simulation.
A Brief Analysis of the Working Load and Stroke of the Linear Actuator for the Passenger Aircraft Cargo Door
Authors: Wang Xiaolu , Wang Danyang , Guo Peng , Niu Guangran , Liu Ruijun , Guo Yucheng
Published: December 2022

Towards the cargo door actuator of the passenger aircraft, the load type during service is analyzed, and the load profile is identified and illustrated. For the door actuation system composed of a rear support beam, linear actuator, door, etc., the theoretical working load and stroke of the actuator are calculated, as well as the load and stroke when the components are elastomers. The comparison results show that the reduction of the door stiffness will increase the actuator load, and the reduction of the rear support beam and actuator stiffness will increase the stroke. This study can provide a reference for engineering problems such as door system stiffness allocation, door opening stroke design, and evaluation.
Simulation of Electric Vehicles Based on Simulink
Authors: Yang Qingzheng
Published: December 2022

Due to the increasing popularity of electric vehicles in recent years, the research and development requirements for electric vehicles are also increasingly high. This paper is based on Simulink modeling simulation and simulation debugging to get the impact of each parameter on the performance of the car. The content includes: understanding the basic structure of pure electric vehicles and related performance requirements; Based on various data summary data, the battery, motor, and other models of the electric vehicle are designed. Learn Matlab, Simulink-related knowledge, and simulation modeling. This paper analyses electric vehicles, the basic mechanism, performance characteristics, and key links of electric vehicles and other parts of the matching design. Finally, the design, modeling, simulation, and testing in the development process of automotive embedded systems can be organically combined to form a relatively complete development mode. Through analysis, it is found that the simulation model of this design plays an important role in improving development efficiency.