bluuebunny/crossref_metadata_2025 huggingface dataset:
WELDABILITY OF COBALT ALLOYS BY HYBRID METHODS
Authors:   FSI VUT Brno, Faculty of Mechanical Engineering, Institute of Welding and Surface Treatment, HERCIK TOMAS , SIGMUND MARIAN ,   FSI VUT Brno, Faculty of Mechanical Engineering, Institute of Welding and Surface Treatment, HRUBY PETR ,   FCH VUT Brno, Faculty of Chemistry, Institute of Material science
Published: October 2021

The article presents the current state of the use of cobalt in various industries and its possible elimination in the field of welding. In this area, it is used in the form of cobalt alloys which are affected by various mechanical and chemical influences. These alloys are produced by the secondary metallurgical area. The primary area is the chemical industry which reserves all the use of cobalt for the production of Li-ion batteries for electric vehicles at an increasing price. The primary area is the chemical industry which reserves all the use of cobalt for the production of Li-ion batteries for electric vehicles at an increasing price. As it becomes unprofitable for other areas, its savings must be sought. From the point of view of welding technology, the solution could be the use of unconventional and hybrid methods that do not require filler material for the connection of elements. Based on these aspects, the methods of a laser beam, electron beam, and combination of a laser beam with TIG method were selected. Verification of the suitability of the use of the mentioned methods was performed on the abrasion-resistant alloy Stellite 6B. The quality of the joints was evaluated by destructive methods such as microstructure, macrostructure, microhardness, and EDS. After evaluating the results of all samples, the hybrid method in the combination of a laser beam and TIG method seems to be the best.
CRYOGENIC MILLING OF METASTABLE AUSTENITIC STAINLESS STEEL AISI 347
Authors:   TU Kaiserslautern, Institute for Manufacturing Technology and Production Systems, Gutzeit K. , Basten S. ,   TU Kaiserslautern, Institute for Manufacturing Technology and Production Systems, Kirsch B. ,   TU Kaiserslautern, Institute for Manufacturing Technology and Production Systems, Aurich J.C. ,   TU Kaiserslautern, Institute for Manufacturing Technology and Production Systems
Published: October 2021

The metastable austenitic stainless steel AISI 347 offers the possibility to induce a phase transformation from γ-austenite to ε- and α’-martensite when machining. This knowledge is well understood during cryogenic turning and was already applied to improve the surface morphology of metastable austenitic steel. However, the potential of this in-process hardening method is so far limited to rotationally symmetrical components. The aim of this study is to investigate deformation induced phase transformation during cryogenic milling, aiming at an improved surface morphology and at the resulting beneficial surface properties of the workpiece for parts with complex geometries.
DEMONSTRATION OF A NEW APPROACH FOR MEASURING TOOLS WITH THE IMPINGEMENT SOUND OF AN AIR JET USING MACHINE LEARNING
Authors:   University Erlangen-Nuremberg, Institute of Resource and Energy Efficient Production Systems, Wuerschinger H. , Gross D. ,   University Erlangen-Nuremberg, Institute of Resource and Energy Efficient Production Systems, Muehlbauer M. ,   University Erlangen-Nuremberg, Institute of Resource and Energy Efficient Production Systems, Stadler M. ,   University Erlangen-Nuremberg, Institute of Resource and Energy Efficient Production Systems, Hanenkamp N. ,   University Erlangen-Nuremberg, Institute of Resource and Energy Efficient Production Systems
Published: October 2021

Monitoring the tool condition of machining processes is important but challenging. Several automated tool condition monitoring solutions are available, but often not used due to existing restrictions or disadvantages. A new approach can be the detection and measurement of tool conditions analyzing the sound of an air jet impingement on tools. Due to the availability of compressed air as a working and cleaning medium for many processes, this approach can be used for various condition monitoring and measuring tasks. In this paper the procedure and its functionality are first presented on simple shapes and then tested on the tool wear of inserts.
MODELLING OF PROCESS FORCES FOR COMPLEX MULTIAXIAL TURNING PROCESSES
Authors:   Leibniz Universitaet Hannover, Institut fuer Fertigungstechnik und Werkzeugmaschinen, Denkena B. , Kroedel A. ,   Leibniz Universitaet Hannover, Institut fuer Fertigungstechnik und Werkzeugmaschinen, Ellersiek L. ,   Leibniz Universitaet Hannover, Institut fuer Fertigungstechnik und Werkzeugmaschinen, Zender F. ,   Leibniz Universitaet Hannover, Institut fuer Fertigungstechnik und Werkzeugmaschinen
Published: October 2021

Increasing demands regarding productivity and component quality are a major challenge in turning. To meet these demands, complex multiaxial turning processes like enhanced variants of the trochoidal turn-ing processes are increasingly used. For these processes, the tool path is optimized to achieve advanta-geous cutting conditions and thus higher productivity. However, the process forces and their relations to the process parameters for these processes are currently unknown, which complicates the process de-sign and calculation of required clamping forces. This paper presents a simulation based approach to estimate the process forces of complex multiaxial turning processes. Therefore, a dexel based material removal simulation is used to calculate the chip parameters, e.g. undeformed chip thickness, and the chip cross-sectional area. On this basis, the process forces are modelled as a function of the undeformed chip thickness and undeformed chip width. By this, the force model is parameterized and the calculated process forces are validated by comparison with process force measurements.
EXPERIMENTAL ANALYSIS OF THE ETCHING PROCESS FOR VALIDATION OF NON-CONVENTIONAL SLOT MACHINING IN AERO ENGINE COMPONENT MANUFACTURING
Authors:   Rolls-Royce Deutschland Ltd. & Co. KG, Germany, Baier C. , Weigold M. ,   Technical University of Darmstadt, Institute for Production Management, Technology and Machine Tools
Published: October 2021

To fulfill service life and integrity requirements when using a non-conventional process in aerospace industry, a comprehensive validation needs to be carried out. According to the state of the art, the characteristically resulting recast layer of wire electrical discharge machining (WEDM) can be reduced to a few microns. To meet existing requirements for eliminating the recast layer, it is essential for validation to consider the complete process chain consisting of WEDM and the subsequent processes. In this paper, the subsequent process etching in series production is investigated with regard to its suitability for the removal of the white brittle surface layer without leaving any residues. By using a Design of Experiment approach, the residue-free removal of the recast layer by electrolytic etching is investigated.
NUMERICAL METHODS FOR THE SIMULATION OF SEGMENTED CHIPS AND EXPERIMENTAL VALIDATION IN MACHINING OF TI-6AL-4V
Authors:   University of Stuttgart, Institute for Machine Tools, Menze C. , Wegert R. ,   University of Stuttgart, Institute for Machine Tools, Reeber T. ,   University of Stuttgart, Institute for Machine Tools, Erhardt F. ,   University of Stuttgart, Institute for Machine Tools, Moehring H.-C. ,   University of Stuttgart, Institute for Machine Tools, Stegmann J. ,   Leibniz University Hannover, Institute of Thermodynamics
Published: October 2021

The simulation of machining processes holds the opportunity for process improvement on many levels. Possible benefits that can be derived from accurate representations of the real processes on the tool from simulations include a prediction of tool wear, the shape of the chips produced, the forces, frictions and temperatures that arise and the residual stresses in the workpiece. These predictions can be used to improve the process in terms of its economic and ecological behaviour: Increasing the service life of the tools used through an improved understanding of the tool-workpiece interaction. The finite element method (FEM), among others, has emerged as a common method for simulating these processes. When simulating machining processes using FEM, a major challenge is to avoid or compensate for the mesh distortions caused by the massive, fast-moving deformation processes, but at the same time to allow the mesh to be discretised in some way to ensure chip removal. To this end, various approaches will be presented in the course of this work and the mesh-based approaches will be explored in depth. Among other things, a remeshing approach for these investigations was developed. The machining of TI6AL4V is used to illustrate these approaches, as its tendency to form segmented chips is particularly challenging to model.
INVESTIGATION OF LUBRICATING OILS FROM RENEWABLE RESOURCES FOR CRYOGENIC MINIMUM QUANTITY LUBRICATION
Authors:   University Erlangen-Nuremberg, Institute for Resource and Energy Efficient Production Systems, Meier T. , Gross D. ,   University Erlangen-Nuremberg, Institute for Resource and Energy Efficient Production Systems, Hanenkamp N. ,   University Erlangen-Nuremberg, Institute for Resource and Energy Efficient Production Systems
Published: October 2021

Cryogenic minimum quantity lubrication using liquid carbon dioxide (CO2) has increasingly become the focus of research in recent years. With this cooling strategy it is possible to cool and lubricate the cutting zone individually by regulating the oil and liquid CO2 flow. The oil used has a significant influence on the process stability and performance. The aim of this study is to identify the influence of 15 different base oils from renewable sources on a milling process of X2CrNiMo17-12-2 with cryogenic minimum quantity lubrication. For this purpose, a non additivated sunflower, coconut and rapeseed oil and additional bio-based oils, such as synthetic ester and fatty alcohol, will be tested and compared to a conventional mineral oil regarding wear, process forces and productivity. In addition, the impact of the bio-based oils on rough turning of X2CrNiMo17-12-2 and finishing turning of 100Cr6 with cryogenic minimum quantity lubrication is evaluated and compared to the milling performance. The results have been analyzed in comparison to conventional emulsion flood cooling and recommendations have been given for the future development of sustainable lubricants to be applied with cryogenic cooling strategy.
INFLUENCE OF CONTOUR RADIUS AND FIBER ORIENTATION ON HEAT ACCUMULATION DURING MACHINING OF UNIDIRECTIONAL CFRP
Authors:   Hamburg University of Technology, Institute of Production Management and Technology, Mehnen J. , Hintze W. ,   Hamburg University of Technology, Institute of Production Management and Technology, Koeppe M. ,   Hamburg University of Technology, Institute of Production Management and Technology
Published: October 2021

The production of carbon fiber reinforced plastic (CFRP) parts requires edge trimming after primary shaping. Heat accumulates in convex workpiece sections, leading to increased temperatures compared to straight edges, possibly compromising the material. Existing analytical models assume constant thermal conditions and are therefore unable to calculate temperature fields of curved workpiece contours. Accordingly, a numerical simulation for straight contours was extended to convex geometry sections with different radii. The paper outlines this temperature simulation and presents results for various radii and fiber orientations when machining unidirectional CFRP. Temperature measurements during milling of unidirectional CFRP are used to calibrate the simulation.
FRAMEWORK FOR COUPLED DIGITAL TWINS IN DIGITAL MACHINING
Authors:   ModuleWorks GmbH, Aachen, Germany, Plakhotnik D. , Curutiu A. ,   Module Works SRL, Bucharest, Romania, Zhulavskyi A. ,   Sumy State University, Sumy, Ukraine, Beudaert Xavier ,   IDEKO S Coop: Elgoibar, Spain, Munoa Jokin ,   IDEKO S Coop: Elgoibar, Spain, Stautner M. ,   ModuleWorks GmbH, Aachen, Germany
Published: October 2021

This paper presents a further elaboration of the use of the digital twin concept in digital machining. The main goal of the research is an attempt to combine digital representations of different objects involved in the machining process in a holistic manner. Digital twins of the in-process workpiece, cutting tool, clamping, and machine tool along with the process twin are connected in a framework in which all these elements can influence each other. The framework shows different levels of integration of different digital twins and practical recommendation on the implementation. Besides, the framework supports a simulation layer that provides data for the intensity of the interaction. Such interactions can result in, for instance, cascading calculations of cutter workpiece engagement, cutting forces, tool wear, tool deflection, chatter, and so on. Eventually, a design for a software mockup was elaborated to present the developed framework. The entire workflow to simulate part machining in such a digital representation can be used as an ultimate tool for CAM simulation and NC verification within the Zero Defect Manufacturing paradigm.
UTILIZATION OF MACHINE LEARNING APPROACHES FOR TOOL WEAR DETECTION AND PREDICTION IN THE CIRCULAR SAWING PROCESS OF METALLIC MATERIALS
Authors:   University of Stuttgart, Institute for Machine Tools, Georgi P. , Eschelbacher S. ,   University of Stuttgart, Institute for Machine Tools, Moehring H.-C. ,   University of Stuttgart, Institute for Machine Tools
Published: October 2021

Efficiency plays a major role in many areas of the mechanical processing of metals. Especially in basic provision of raw material, for example by cutting components to length during sawing, high penetration and thus efficiency as well as high robustness of the process is required. Here, the sawing tool and its durability is the decisive component in the process. In today's state of the art, at least in modern sawing machines, the condition is recorded via the sawing tool course or also via the motor current. This gives the operator an initial indication of the tool condition. In current machines an extensive sensory recording for e.g., accelerations as a characteristic for the tool condition is not used. The aim of the investigations described in the paper was to use measurement data from various internal and external sensors to record the state of the sawing tool wear and to analyse it using machine learning approaches. For this purpose, cutting tests were carried out on a modern sawing centre and the acquired measurement data were an-alysed using a convolutional neural network (CNN). During the tests, the internal and external sensors were compared to show which of the sensors used provides the best results in detecting wear on sawing tools. The investigations show that the CNN is suitable for detecting tool wear by means of the sensors used, which can be used for on-line monitoring. Finally, an outlook is given, and it is shown how the CNN can be used for active control in the sawing process.
DEVELOPMENT OF A MEASURING AND CONTROL UNIT FOR AN INTELLIGENT ADJUSTMENT OF PROCESS PARAMETERS IN SAWING
Authors:   University of Bayreuth, Chair Manufacturing and Remanufacturing Technology, Schreiner F. , Thorenz B. ,   University of Bayreuth, Chair Manufacturing and Remanufacturing Technology, Schmidt J. ,   University of Bayreuth, Chair Manufacturing and Remanufacturing Technology, Friedrich M. ,   University of Bayreuth, Chair Manufacturing and Remanufacturing Technology, Doepper F. ,   Fraunhofer IPA Project Group Process Innovation, Germany
Published: October 2021

Sawing frozen wood differs significantly from sawing unfrozen wood. Temperatures below zero degrees result in an increasing hardness of wood, rising cutting forces and a progression of tool wear. Currently, the adaption of process parameters due to different wood temperatures is based on operator experience, leading to overloaded saw blades, hence causing considerable economic damage by increasing production downtime. This paper presents the development of a measuring and control unit featuring an integrated database of processing values enabling operators to use most suitable process parameters, thus extending the service life of circular saw blades and increasing the performance of sawmills.
IDENTIFICATION OF THE ROOT CAUSE OF SURFACE TOPOGRAPHY INACCURACIES BY MEANS OF PROCESS MONITORING: INDUSTRIAL EXAMPLES
Authors:   Ideko, Dynamics and Control, Elgoibar, Spain, Gil M. , Beudaert X. ,   Ideko, Dynamics and Control, Elgoibar, Spain, Munoa J. ,   Ideko, Dynamics and Control, Elgoibar, Spain, Barrenetexea D. ,   Ideko, Dynamics and Control, Elgoibar, Spain, Sanchez J.A. ,   University of the Basque Country, Department of Mechanical Engineering, Bilbao, Spain
Published: October 2021

The surfaces of machined workpieces contain the signature of the manufacturing process. Indeed, the surface inaccuracies can be related to process parameters and machine vibrations. This paper aims at using process monitoring to identify the origin of surface topography defects. Thus, vibration and other process parameter measurements are correlated with profile measurements to establish the relationship between vibrations and surface topography for various process conditions. As each machine and process anomaly is reflected differently in the time and frequency domain, different analyses are applied both to temporal signals such as vibrations and to geometric signals obtained from the micro-geometry of the workpiece. Experimental results validate the diagnostic method and verify that the procedure is effective for the identification of topography defects originated not only from chatter vibrations but also from forced vibration coming from the kinematical chain (unbalance, beating...). The diagnostic method is successfully applied in various machining operations such as turning and grinding.
DYNAMIC CHARACTERIZATION OF MILLING BASED ON INTERRUPTED FEED MOTION
Authors:   MTA-BME Lendulet Machine Tool Vibration Research Group, Department of Applied Mechanics, Budapest University of Technology and Economics, Kiss Adam K. , Bachrathy D. ,   Department of Applied Mechanics, Budapest University of Technology and Economics
Published: October 2021

This study presents an experimental method for detecting and avoiding chatter vibrations that occur during general milling processes. The main idea is to capture the so-called dominant spectral properties from the transient vibrations of the milling process, which gives a good approximation for its dynamical behavior and provides a quantitative measure of stability. To induce transient vibration, the machining process is momentarily interrupted. Therefore, the method offers the possibility that the stability limit can be forecasted by extrapolation from stable and accurate measurement points without reaching harmful vibration on the machine tool. We present laboratory tests with momentary interrupted straight tool path to demonstrate the applicability of the proposed method.
MULTI-PHASE SIMULATION OF THE LIQUID COOLANT FLOW AROUND ROTATING CUTTING TOOL
Authors:   Chemnitz University of Technology, Institute for Machine Tools and Production Processes (IWP),, Topinka L. , Braeunig M. ,   Chemnitz University of Technology, Institute for Machine Tools and Production Processes (IWP),, Putz M. ,   Fraunhofer Institute for Machine Tools and Forming Technology IWU, Germany, Dix M. ,   Fraunhofer Institute for Machine Tools and Forming Technology IWU, Germany
Published: October 2021

The heat generated during the cutting processes significantly influences the manufacturing accuracy. For many machining tasks, the use of cooling lubricant is essential to achieve the necessary cooling and lubricating effect in the cutting zone. A reduction of a coolant supply due to resource-efficient or ecological efforts has an impact on the temperature field in the cutting tool and clamping system, which affects the thermal behavior of the frame structure and can cause its thermo-elastic deformations leading to machining inaccuracies. In this paper, the multi-phase CFD model for simulation of liquid coolant flow around the cutting tool was developed. The effect of rotation of the cutting tool causing turbulences was taken into account and the simulation of coolant flow was based in Eulerian approach as a continuous flow. Furthermore, this paper considers the modification of the simulation model for thermal simulations of the influence of coolant flow on the temperature field of the cutting tool and clamping system.
USING GAMIFICATION ON THE SHOP FLOOR FOR PROCESS OPTIMIZATION IN MACHINING PRODUCTION
Authors:   Siemens Energy, Industrial Application, Turbo Machinery, Dewald M. , Kohn O. ,   Institute for Production Management, Technology and Machine Tools (PTW), Technical University of Darmstadt, Dehorn Y. ,   Siemens Energy, Industrial Application, Turbo Machinery, Howaldt H. ,   Siemens Energy, Industrial Application, Turbo Machinery, Ebben A. ,   Siemens Energy, Generation, Large Rotating Equipment, Kratzke N. ,   Siemens AG, Digital Industries, Center of Competence, Machine Tool Systems, Janssen F. ,   Siemens Energy, Industrial Application, Turbo Machinery, Weigold M. ,   Institute for Production Management, Technology and Machine Tools (PTW), Technical University of Darmstadt
Published: October 2021

The optimization of production processes is even in 2021 still an up-to-date topic, where the use of data is discussed, and the utilization has proven to be effective in specific applications in the last 10 years. Despite increasing access to information directly from the production process and more available computing resources, the data still holds unused potential. Even ongoing digitalization does not replace a deep understanding of the underlying processes and a focus on online automation misses the potential including expertise of shop floor employees. Thus, besides automation and data-driven improvements it is important to support employees with innovative methods to exploit the full potential of the Internet of Things. Principles of gamification offer an opportunity to incorporate the shop floor personnel, to take their full attention on optimization of the process supporting them in their day-to-day job. Appropriate visualization creates incentives for continuous process optimization.
METHOD FOR SAFE EXPERIMENTAL TESTING OF MACHINE TOOL USABLE SPINDLE POWER
Authors:   Czech Technical University in Prague, Czech Institute of Informatics, Robotics and Cybernetics, Department of Industrial Production and Automation, Kolar P. , Janota M. ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, Research Centre of Manufacturing Technology, Sveda J. ,   Czech Technical University in Prague, Czech Institute of Informatics, Robotics and Cybernetics, Department of Industrial Production and Automation, Kozlok Tomas ,   TOS Varnsdorf a.s., Varnsdorf, Czech Republic
Published: October 2021

The regenerative chatter during milling is a consequence of the machine tool dynamic compliance and the specific setting of the cutting process. The basic request on the machine structure is to enable a stable cut with dominant portion of the installed spindle power. In order to improve the dynamic properties of newly-designed machine tools, the machine tool structures are optimized using various advanced simulation methods and are made of various advanced materials. The final design should be tested experimentally. The test of usable spindle power provides important feedback on the machine tool design. The testing of large machine tools is time consuming due to the significantly varying machine dynamic compliance dependent on the working space. Due to the installed high power and large diameter tools used, the occurrence of chatter might be dangerous with a high risk of machine tool damage. The article presents a method for the safe and time-effective experimental testing of the machine tool usable spindle power. The method is based on the experimental identification of the cutting force coefficients and the experimental identification of machine tool behavior with the support of extrapolation models based on identified experimental data. The dynamic compliance is measured within a rough network of measurement points in the machine working space. The measured dynamic compliance results are characterized by a model based on modal identification data. Only a few cutting tests are done for the cutting force coefficient identification. Finally, a map of the usable spindle power is calculated. This approach makes it possible to calculate the results with respect to the real machining process and the current machine tool conditions across the whole working space in an acceptable time. The approach is demonstrated on a real case study.
Synthesis and Characterization of Magnesium Acetate Doped MAPbI3 Perovskite Solar Cells with Carbon Electrodes
Authors:   Department of Physics, Universitas Negeri Malang, Yusra Deris Afdal , Mufti Nandang ,   Department of Physics, Universitas Negeri Malang, Latifah Eny ,   Department of Physics, Universitas Negeri Malang
Published: October 2021

The organometal perovskite trihalide (MAPbI3) based solar cell has attracted the attention of many researchers because it has the potential to be a third-generation solar cell that has high efficiency, flexibility and transparency. However, this perovskite solar cell is sensitive to the environment and less stable. In this study, a performance study of perovskite solar cells with the addition of magnesium acetate was carried out in the MAPbI3 synthesis process and the use of carbon electrodes. In general, the perovskite solar cell arrangement in this study consisted of ITO/TiO2 mp/MAPbI3/carbon paste. Mesoporous TiO2 (mp) coating was carried out using the screen printing method, while MAPbI3 coating was carried out with a two-stage spin coating with the addition of magnesium acetate after PbI2 coating in the first stage. The samples obtained were then characterized using an X-Ray Diffractometer (XRD). Analysis of the performance of solar cells was carried out by measuring I-V and photoresponses using a solar simulator. XRD results show that MAPbI3 film has been formed even though there is still impurity of PbI2. The resulting solar cell performance has a value of Voc equals 3.45 V and Jsc equals 0.04 with an efficiency of around 0.09 per cent. In the measurement of the response photo, the increase in time value was 7.29 s and the decay time was 34.38 s. The low-efficiency value is probably due to the absence of a layer of hole transfer materials (HTM) and the presence of PbI2 impurities. However, the stability of the photoresponse pattern against time has shown quite good results even though the response is increased or the decay is slow.
Trayectorias del pensamiento crítico social y ambiental desde la investigación. Caso Maestría de Desarrollo Sostenible y Medio Ambiente
Authors: Torres-Mendivelso Marisol , García-Naranjo Martha Lucia
Published: October 2021

Se presentan los resultados del estudio documental que tuvo como objetivo interpretar las trayectorias del pensamiento crítico social y ambiental en las tesis de la Maestría en Desarrollo Sostenible y Medio Ambiente de la Universidad de Manizales. La metodología utilizada fue cualitativa con alcance interpretativo, para lo cual se empleó la revisión sistemática de literatura y el análisis categorial como recursos metodológicos; las fases de la investigación fueron la exploración y el análisis documental de 76 tesis desarrolladas entre 2007 y 2018, con una organización en dos categorías: la racionalidad social y la racionalidad ambiental. Respecto a la racionalidad social se encontró un enfoque del desarrollo humano a partir de la postura de los investigadores para el examen crítico de sí mismo y de las propias tradiciones, la habilidad para un pensamiento desde la diversidad y la pluralidad y la necesidad de entender los sufrimientos ajenos.Y en la racionalidad ambiental, los investigadores demuestran su postura en torno a la racionalidad sustantiva, teórica, técnica y cultural para identificar y reducir las problemáticas ambientales. Se idéntico la línea del pensamiento lógico disciplinar para posteriores estudios.
EDITORIAL - Investigación para la transformación digital o la inutilidad del neoliberalismo para enfrentar la crisis generada por la pandemia COVID-19
Authors: Ríos Alvarado Arnaldo
Published: October 2021

La pandemia de COVID-19 está generando la renovación de técnicas de gobierno que se amplían a medida que se ensanchan los aspectos que permiten el crecimiento económico esperado con los procesos de transformación digital, mismos que ya demandan esfuerzos y recursos de inversión en investigación, en ciencia, en tecnología y en innovación por parte de los diferentes Estados y gobiernos. Las acciones llevadas a cabo por Estados y organismos multilaterales para atender la pandemia de COVID-19 generan transformaciones digitales en educación, transporte, salud, agricultura, derecho, conformación de ciudades, arquitectura, industria, trabajo y economía. Estas técnicas de gobierno contemporáneas tienen su inicio en Europa, y, modernamente, a fines del siglo XVIII, cuando la economía empieza a fluir de manera independiente, por fuera de las culturas, de los pueblos, de las tradiciones, de los valores y Occidente hegemónico logra mercantilizar las relaciones humanas (trabajo alienado) y la tierra (cuerpo inorgánico del hombre). Las comunidades y las naturalezas se convierten en un mecanismo de generación de plusvalía. A fin de garantizar el crecimiento económico, el Estado se torna inmisericorde con las comunidades y con su cuerpo inorgánico.
A Mobile Production Monitoring System Based on Internet of Thing (IoT) and Random Forest Classification
Authors:   Centre for Autonomous Systems and Robotics Research, Faculty of Engineering and Technology, Tunku Abdul Rahman University College, Malaysia, Wong Qiu Yu , Chu Yih Bing
Published: October 2021

Production variations are crucial factors that cause the reduction of production efficiency. These variations are often unpredictable and difficult to be interpreted directly from the production activity of the working station. Automated diagnostic of the causes to variations is therefore the key to overcome the issue. The system should also detect and diagnose variations for all the machines which are placed in the same manufacturing line at the same instance to prevent misaligned of production volume. To achieve this, Internet of thing (IoT) technology is proposed. The technology enables automatic data transfer without the need of human intervention. Through IoT, manufacturers are able to keep track the production activity and resolve problems encountered immediately. In addition, a typical random forest classification model is developed to analyze the production patterns and subsequently identify the causes to the unwanted variations. To the best of authors’ knowledge, this paper presents a first-time work on implementation of a mobile production monitoring system based on IoT and random forest classification. The methodology and technical matter to realize the implementation are highlighted and discussed. Overall, the proposed system has been tested accordingly and visualized through a developed mobile application.
IoT-Based SCADA System Design and Generation Forecasting for Hydropower Station
Authors:   Department of Electronic Engineering, Mandalay Technological University, Mandalay, Myanmar, Myint A. K. , Latt K. Z. , Hla T. T. , Tun N. M.
Published: October 2021

This paper points out controlling to the generator of power station, collecting the required information of the station, analyzing the communication metrics of the SCADA system and predicting the electricity production without hydrological events based on the historical data under the IoT-based SCADA system. SCADA system based on the IoT is the modernization of the SCADA system for hydropower station to get the required information and to conduct the power station for balancing with the national grid in a timely manner. This system supports the varieties of the information of the station such as alarm system, data monitoring and control system, data logging and generated capacity, and so on. Moreover, the performance of the IoT-based SCADA system such as communication metrics is analyzed by using the data packet analyzer and WiFi analyzer. In addition, historical data (generated electricity) is used to analyze and detect the circumstance of the production of hydropower stations and to predict the production for coming year by using the time series analysis. In this research, the actual historical data of the Yeywa hydropower station which is collected by on-ground recording is used for statistical analysis of generated capacity.
Measurement Method for Erector Spinae Muscle Activity during Patient Handling Using Inertial Sensor and Shoe-type Force Sensor
Authors:   Graduate School of Life Science and System Engineering, Kyushu Institute of Technology, Kitakyushu, Japan, Kitagawa Kodai , Matsumoto Koji , Iwanaga Kensuke , Ahmad Siti Anom , Nagasaki Takayuki , Nakano Sota , Hida Mitsumasa , Okamatsu Shogo , Wada Chikamune
Published: October 2021

Because caregivers often experience lower back pain caused by lumbar load from patient handling, monitoring this load can help prevent pain. Erector spinae muscle activity, which is measured and monitored as lumbar load, is commonly measured by electromyography (EMG). However, EMG’s electrodes can cause skin irritation and be uncomfortable. Therefore, measuring muscle activity without electrodes is necessary. In this study, we propose a method for estimating erector spinae muscle activity using wearable sensors, specifically inertial and shoe-type force sensors. Inertial sensors measure acceleration and angular velocity of the trunk. Shoe-type force sensors measure vertical force of the feet. A regression model obtained from a machine learning algorithm can predict erector spinae muscle activity using inertial and force data. In our experiment, we evaluated the accuracy of our method by comparing sensor data with surface EMG data in patient handling. Results show that this method can measure erector spinae muscle activity with a small error (less than 5% maximal voluntary contractions) and a significantly high correlation with actual value (r = 0.891, p <0.05). In addition, a Bland-Altman plot showed no fixed and proportional errors. These findings indicate that our proposed method can accurately monitor the lumbar loads of caregivers.
Domain Knowledge-Based Automatic Voltage Determination System for Welding Machine
Authors:   Hitachi, Ltd. Research & Development Group, Tokyo, Japan, Takahashi Masakazu , Yasui Takuro , Muro Keiro
Published: October 2021

In the manufacturing industry, quality degradation due to a decrease in skilled operators possessing domain knowledge has become a problem. Digitalization using IoT technology has emerged as a means to tackle this problem. In the resistance welding process, welding quality fluctuates depending on aging of electrodes. Experienced operators adjust the welding voltage to keep the quality constant. As this knowledge is difficult to share, the success rate of voltage changes at the time of quality degradation tends not to be improved. Therefore, we developed an automatic voltage determination system that improves both quality and productivity by improving the success rate, which is one of the main measures. The system learns past sensor data and voltage change logs, determines the voltage according to input real-time sensor data, and sets the voltage for the welding machine. We propose three voltage determination methods: a similarity search method, a voltage prediction method using a regression model that outputs voltage, and a quality prediction and voltage search method that searches for the optimum voltage in a classification model to predict the success or failure of voltage changes. Our evaluation of these methods shows that the success rate improves by up to 12.4 percentage points compared to when the operators performed the process manually. This result demonstrates that we can achieve quality stabilization and productivity improvement by implementing our system in the welding process.
Current Signature Analysis for Diagnostics in Motor Bars under Locked Rotor Condition
Authors:   Department of Electrical Engineering, Pontifícia Universidade Católica de Minas Gerais, Belo Horizonte, Brazil, Silva Michael Hrelrison F. da , Jr. Pyramo P. da Costa
Published: October 2021

Three-phase induction motors are widely used in industrial electric applications. To ensure their operability, efforts have been made mainly in the detection of rotor faults. This work aims to detect rotor faults in induction motors through of Motor Current Signature Analysis (MCSA) under locked rotor condition. In this configuration, the procedure is most suitable for drives where the motor operates intermittently, with a short operating stroke or variable speed. This paper proposes a methodology and presents a comparison of consolidated signal processing techniques such as Fast Fourier Transform (FFT), Discrete Wavelet Transform (DWT), and Discrete Hilbert Transform (DHT) applied on the conventional input currents and components of Park transformation in a case study. The objective is to define which of the techniques is the most robust in the process of identifying broken bars in the induction motor for the proposed methodology.
Controversial Issues of ‘Happy 30 Minutes’ After-School Activities Policy in Shanghai
Authors:   Department of Education in East China Normal University, Shanghai, China, Du Yan
Published: October 2021

Most countries have after school programs for children. Such as America, Britain, France etc. Though Shanghai’s primary schools have good infrastructures, they don’t establish a system for after-school activities. In order to enrich pupils after school life and promote all-round development, Shanghai education committee issued the document of Notice on the trial implementation of ‘Happy 30 minutes’ after-school activities in Shanghai primary schools on June 20th, 2017. Not only can each school make full use of the school playground, dedicated classrooms, libraries and other places, but also integrate school resources or share resources with school districts and group member schools, to provide optional activities for pupils. After-school activities include letting students do their homework, calligraphy, art, reading, games, physical exercise, scientific experiments and other interesting activities. There are advantages and disadvantages for Shanghai primary schools to carry out the ‘Happy 30 minutes’ after-school activities. The core controversial issue is whether it is worth to have 30 minutes for after-school activities. Through interviews and literature analysis, the researcher analyzed the controversial issues from four aspects, and provided some suggestions for the ‘Happy 30 minutes’ after-school activities policy.
Exploration about Teaching/Learning Activities in Universities from the Perspective of Active Learning
Authors:   School of Computer Science and Technology, Guizhou University, Guiyang, China, Dai Dan , Zhang Xinggang
Published: October 2021

Active learning is a learner-centered method of learning. This article introduces active learning, explores the research, discusses its value, explores the framework of active learning, offers suggestions for implementing it, and provides some concrete examples of active learning approaches in Universities: Think-Pair-Share, Jigsaw, Class Game, Student debate, PBL.
Special Issue Editorial: Significance of STEM Education in Teaching and Learning for the Changing World with COVID19
Authors:   La Trobe University, Melbourne, Australia, Kurup Premnadh M , Dong Yan
Published: October 2021

We have great pleasure in releasing this special edition on “Significance of STEM Education in Teaching and Learning for the Changing World with COVID19”, which focused on the importance of STEM education during these challenging COVID 19 scenarios. Integrated approaches to teaching and learning, and teacher preparation are key aspects to be focused on to nurture a responsible generation that is motivated and proficient in STEM. This would open new avenues for changing the existing practices and might lead to innovations that would have an influence on contemporary lifestyle practices. These are unknown, unpredictable and uncertain times, requiring unprecedented experimentations with new choices to reverse or enhance established practices. It is certainly tough to deal with many difficulties in daily life, let alone in in research, teaching and learning settings. We must confront these times with resilience to face the challenges and find alternative routes to forward. This would most likely include a timeline from inception to conclusion of current practices and a roadmap for future practices.
Integrative Behavioral Health (IBH) Model at the Intersections of the Philippine Mental Health Law, Education, and Policy: For COVID-19 Recovery and Beyond
Authors:   NINR, National Institutes of Health, Bethesda, MD USA, Billones Ruel R. , Jr. Sam Aquino , Pusta Rey Jan , Victolero-Tupas Marie Joyce
Published: October 2021

The COVID-19 pandemic has impacted the mental health of Philippine citizens. The authors propose the Integrative Behavioral Health (IBH) model to help facilitate the country’s eventual recovery from a health psychology perspective. Findings were integrated from a faculty consultation from a private university’s psychology department, a literature review, and a survey of students who are learning online. The survey results revealed that living with family members negatively correlated with readiness to learn online, r = -.37, p < .05. Further research is needed. Furthermore, combining themes gathered from the consultation, literature review, and variables used from the survey served as anchor words for the IBH model: 1. Emancipatory Education; 2) Filipino Psychology; 3) Contextualization; 4.) Philippine Mental Health Law; 5). Symptom Science; and 6) Social Determinants of Health (SDH). The constructs were implemented into an online health psychology course. The proposed curriculum design provides for an effective mental health response towards post-pandemic recovery.
Post COVID Foundation Biology through Interactive Online Learning
Authors:   School of Environment & Rural Science, University of New England, Armidale, Australia, Burns Adrienne , Labeur Lea , Andronicos Nicholas
Published: October 2021

The rapid migration of courses from blended teaching to a fully online learning environment during the COVID-19 pandemic required the timely development of new, online teaching resources and re-imagined strategies, to teach practical skills to university students. The move to deliver content that was fully online challenged the assumptions and conventions about the use of face-to-face classes, especially in STEM disciplines that rely on experiential learning. This critical review uses case studies to describe the innovations that were used to adapt undergraduate, first year (foundation) biology courses which were previously delivered using a blended learning pedagogy to a fully online format. In doing so, the opportunities to enhance traditionally practical based activities have also been considered. Future innovations for blended learning, however, require inherent properties and capacity of technologies to support aligned learning tasks. Reflections on the crisis response to learning however, act as a catalyst for educational change towards more flexible models and practices in future interconnected learning environments.
A Community-Based Capstone Design Project to Build an Automated Urban Greenhouse
Authors:   Department of Electrical and Computer Engineering and Computer Science, York College of Pennsylvania, York, PA, USA, Meah Kala , Blanding Wayne , Moscola James , Hesson Nicole
Published: October 2021

Over the past few years, the engineering programs at York College of Pennsylvania have added more community-based projects into the two-course capstone design sequence that all engineering majors take in their senior year. With capstone design already organized as a multi-disciplinary project-based learning course, it was a natural extension to develop opportunities for community-based projects. As a part of the initiative an automated urban greenhouse was designed, built, and delivered to a local city school to engage school students in sustainability and developing food awareness. A curriculum is being designed to include the greenhouse into the school activities. This paper discusses the process of including community-based projects into capstone projects involving a multidisciplinary student team. Expectations of the community-based project are presented. Detailed descriptions of the mechanical system, the electrical system, the sensor network, and the programmable logic controller are presented. System integration, on-site testing, and student outcomes assessment are also included.
Exploring the Path of Party Building for Grassroots Students in Art Colleges and Universities
Authors:   National Academy of Chinese Theatre Arts, Beijing, People's Republic of China, Zhang Yao , Zheng Wei
Published: October 2021

The purpose of art colleges and universities is to train outstanding artistic talents for the socialist cultural cause of our country. It is an important part of the education work of colleges and universities to train the successors of the party and qualified builders of the socialist cause. This article discusses the importance of the grass-root students' party construction with examples, deeply analyzes the problems found in the party construction practice, summarizes the international cultural exchange department student party branch in the party construction experience, explores the method of art college students' party construction at the grass-roots level path, for further solidification of the students' party construction at the grass-roots level.
Introducing Machine Learning with Scratch and Robots as a Pilot Program for K-12 Computer Science Education
Authors:   Department of Mathematics and Computer Science, Lawrence Technological University, Southfield, Michigan, USA, Chung Chan-Jin , Shamir Lior
Published: October 2021

Machine learning (ML), a branch of artificial intelligence (AI), is a method that enables systems to learn from data for the purpose of recognizing patterns and making decisions without being explicitly programmed. In the past decade machine learning has been growing rapidly, and ML technologies such as speech recognition, spam filters, smart email reply, online recommendations, face recognition, fake news detection, and self-driving cars have become pivotal in modern daily life. However, computer science education has not yet fully adjusted to the tremendous growth in the sub-field of AI. This paper describes an approach of introducing K-12 students to ML through an on-line summer camp. The students are introduced to the concept of ML by hands-on activities of developing applications for recognizing text, numbers, sounds, images, and video data using a web-based cloud service tool "Machine Learning for Kids" and Scratch 3 programming language combined with Lego Mindstorms EV3 robots. The results show that the tools and technologies used in the camp are suitable for K-12 students, also when used in the form of online training. Pre and post surveys show that students express basic knowledge in ML and higher interest in coding and STEM after being exposed to the proposed training.