Inventions

12 pages, 3253 KiB

Open AccessArticle

Ultrasonic Synthesis of Nanochitosan and Its Size Effects on Turbidity Removal and Dealkalization in Wastewater Treatment

by Fitri Khoerunnisa, Yustika Desti Yolanda, Mita Nurhayati, Firdha Zahra, Muhamad Nasir, Pakorn Opaprakasit, Min-Yee Choo and Eng-Poh Ng

Inventions 2021, 6(4), 98; https://doi.org/10.3390/inventions6040098 - 20 Dec 2021

Cited by 13 | Viewed by 3745

Abstract

A detailed study on the synthesis of chitosan nanoparticles under ultrasonication is reported in this paper. By using this simple technique, chitosan particles in nanometer range can be easily prepared without using any harmful and expensive chemicals. The results show that increasing the [...] Read more.

A detailed study on the synthesis of chitosan nanoparticles under ultrasonication is reported in this paper. By using this simple technique, chitosan particles in nanometer range can be easily prepared without using any harmful and expensive chemicals. The results show that increasing the ultrasonic irradiation time and ultrasonic wave amplitude are the key factors for producing discrete chitosan nanoparticles with narrow particle size distribution. The resulting nanoparticles show superior turbidity removal efficiency (75.4%) and dealkalization (58.3%) in wastewater treatment than the bulk chitosan solid (35.4% and 11.1%, respectively), thus offering an eco-friendly and promising approach for treating wastewater via the coagulation/flocculation process. Full article

(This article belongs to the Section Inventions and Innovation in Surface Science and Nanotechnology)

► Show Figures

Figure 1

16 pages, 663 KiB

Open AccessArticle

Analysis of Some Essential Aspects Related to the Navigation Conditions on the Danube River

by Andra Luciana Marcu Turcanu, Liliana Mihaela Moga and Eugen Victor Cristian Rusu

Inventions 2021, 6(4), 97; https://doi.org/10.3390/inventions6040097 - 17 Dec 2021

Cited by 2 | Viewed by 2060

Abstract

The European Union has emphasized the creation of an appropriate framework to optimize the internal market and inland transport waterways, and remove barriers to their wider use. Administrative barriers in the logistics of goods on the Danube waterway and its navigable tributaries constitute [...] Read more.

The European Union has emphasized the creation of an appropriate framework to optimize the internal market and inland transport waterways, and remove barriers to their wider use. Administrative barriers in the logistics of goods on the Danube waterway and its navigable tributaries constitute a significant obstacle to the efficient and sustainable use of the Danube as the region’s central transport hub. The approach proposed in this paper was designed to identify and analyze the relationship between the main variables leading to problematic inland waterway traffic, in this case, on the Danube, and the measures taken by the European Commission to improve it. In terms of the applied research method, “Quality Function Deployment” (QFD), we assign global (overall) and local priority degrees. The proposed framework for adapting QFD as a tool for improving quality and, therefore, performance, aims to identify and prioritize directions for this improvement. The House of Quality (HOQ) is the tool that links areas for improvement to technical requirements. The disclosure of these connections helps identify and prioritize the technical features that will generate the most significant improvements. Full article

(This article belongs to the Special Issue Perspectives and Challenges in Doctoral Research—Selected Papers from the 9th Edition of the Scientific Conference of the Doctoral Schools from the “Dunărea de Jos” University of Galaţi)

► Show Figures

Figure 1

14 pages, 2334 KiB

Open AccessArticle

Analysis of Platform Leveling Systems for Tracked Feller-Buncher Machines

by Andronov Alexandr, Bacherikov Ivan and Zverev Igor

Inventions 2021, 6(4), 96; https://doi.org/10.3390/inventions6040096 - 30 Nov 2021

Cited by 2 | Viewed by 3652

Abstract

The study was devoted to the analysis of feller buncher platform leveling systems. The widespread use of these systems in the design of modern feller-buncher machines makes the study relevant to assess operational efficiency. The analysis was conducted in five stages using analytical [...] Read more.

The study was devoted to the analysis of feller buncher platform leveling systems. The widespread use of these systems in the design of modern feller-buncher machines makes the study relevant to assess operational efficiency. The analysis was conducted in five stages using analytical and stochastic mathematical modeling methods. In the first stage, the existing layouts of alignment systems were analyzed from the position of force on the hydraulic cylinder rods of the platform tilt drive. The three-cylinder layout scheme, where the force on the hydraulic cylinder rod was 50…60% less than that on the two-cylinder layout, appeared to be the most expedient. In the second stage, a mathematical model for determining changes in the position of the center of mass of the feller-buncher depending on the inclination angle of the platform was derived. In the third stage, a mathematical model was derived for determining the limiting angle of slope of the terrain when the feller buncher moved up the slope. For this purpose, two calculation schemes were considered when the machine moved up the slope without and with a tilted platform. Zero support reaction on the front roller was taken as the stability criterion. In the fourth stage, a mathematical model for determining the limiting angle of slope of the terrain during the roll of the feller-buncher machine was obtained. In the fifth stage, the efficiency of the application of leveling systems was evaluated. A graph of the dependence of changes in the terrain slope angle on the platform slope angle was plotted, and a regression dependence for an approximate estimate was obtained. A regression analysis was also carried out, and dependencies were obtained to determine the weight of a feller-buncher with a leveling system and the added pressure on the ground caused by the increase in the weight of the base machine. The analysis of platform leveling systems showed the effectiveness of their application in the designs of feller-buncher machines, as it allows the machines to work on slopes with an inclination of 50…60% more than without them. Full article

(This article belongs to the Section Inventions and Innovation in Design, Modeling and Computing Methods)

► Show Figures

Figure 1

16 pages, 8021 KiB

Open AccessArticle

The Impact of Cattaneo–Christov Double Diffusion on Oldroyd-B Fluid Flow over a Stretching Sheet with Thermophoretic Particle Deposition and Relaxation Chemical Reaction

by Bheemasandra M. Shankaralingappa, Ballajja C. Prasannakumara, Bijjanal J. Gireesha and Ioannis E. Sarris

Inventions 2021, 6(4), 95; https://doi.org/10.3390/inventions6040095 - 25 Nov 2021

Cited by 26 | Viewed by 2580

Abstract

The current study focuses on the characteristics of flow, heat, and mass transfer in the context of their applications. There has been a lot of interest in the use of non-Newtonian fluids in biological and technical disciplines. Having such a substantial interest in [...] Read more.

The current study focuses on the characteristics of flow, heat, and mass transfer in the context of their applications. There has been a lot of interest in the use of non-Newtonian fluids in biological and technical disciplines. Having such a substantial interest in non-Newtonian fluids, our goal is to explore the flow of Oldroyd-B liquid over a stretching sheet by considering Cattaneo–Christov double diffusion and heat source/sink. Furthermore, the relaxation chemical reaction and thermophoretic particle deposition are considered in the modelling. The equations that represent the indicated flow are changed to ordinary differential equations (ODEs) by choosing relevant similarity variables. The reduced equations are solved using the Runge–Kutta–Fehlberg fourth–fifth order technique (RKF-45) and a shooting scheme. Physical descriptions are strategized and argued using graphical representations to provide a clear understanding of the behaviour of dimensionless parameters on dimensionless velocity, concentration, and temperature profiles. The results reveal that the rising values of the rotation parameter lead to a decline in the fluid velocity. The rise in values of relaxation time parameters of temperature and concentration decreases the thermal and concentration profiles, respectively. The increase in values of the heat source/sink parameter advances the thermal profile. The rise in values of the thermophoretic and chemical reaction rate parameters declines the concentration profile. Full article

(This article belongs to the Special Issue Recent Trends in Nanofluids III)

► Show Figures

Figure 1

20 pages, 5303 KiB

Open AccessData Descriptor

Identification and Classification of the Tea Samples by Using Sensory Mechanism and Arduino UNO

by Amruta Patil, Mrinal Bachute and Ketan Kotecha

Inventions 2021, 6(4), 94; https://doi.org/10.3390/inventions6040094 - 25 Nov 2021

Cited by 8 | Viewed by 4454

Abstract

Tea is the most popular hot beverageworldwide. In 2020, the value of the global tea market was almost USD 200 billion, and is estimated to reach up to USD 318 billion by the year 2025. Tea has been included as part ofa regular [...] Read more.

Tea is the most popular hot beverageworldwide. In 2020, the value of the global tea market was almost USD 200 billion, and is estimated to reach up to USD 318 billion by the year 2025. Tea has been included as part ofa regular diet for centuries because of its various health benefits. However, tea is acidic, and over-consumption causes heat problems, disturbance of the sleep cycle, tooth erosion, and low calcium absorption in the body. Strong tea concentration is very harmful and toxic. The safe consumption of tea should be guaranteed. The treatment applied in this research work is on sensory mechanisms and Arduino UNO. The objective of this paper is to find out community interest in a particular tea species and inform them about tea overdose.The acidity is mapped with tea taste in terms of strong, medium, and low flavors. Based on the data analysis, the results differentiatethe acidity level of black tea (pH: 3.89–4.08) as very high, green tea (pH: 4.68–4.70) is in the 2nd position, and the energy drink Herbalife Nutrition (pH: 5.59–5.64) is the least acidic comparatively, with a proportion ratio 1:10 of tea to water. Experimental analysis reveals that in the additives, lemon is most acidic, followed byginger, lemongrass, and Tulasi. Full article

(This article belongs to the Section Inventions and Innovation in Design, Modeling and Computing Methods)

► Show Figures

Figure 1

12 pages, 2013 KiB

Open AccessArticle

Effects of In-Process Temperatures and Blending Polymers on Acrylonitrile Butadiene Styrene Blends

by Muhammad Harris, Johan Potgieter, Hammad Mohsin, Karnika De Silva and Marie-Joo Le Guen

Inventions 2021, 6(4), 93; https://doi.org/10.3390/inventions6040093 - 24 Nov 2021

Cited by 4 | Viewed by 2996

Abstract

Acrylonitrile butadiene styrene (ABS) is a renowned commodity polymer for additive manufacturing, particularly fused deposition modelling (FDM). The recent large-scale applications of 3D-printed ABS require stable mechanical properties than ever needed. However, thermochemical scission of butadiene bonds is one of the contemporary challenges [...] Read more.

Acrylonitrile butadiene styrene (ABS) is a renowned commodity polymer for additive manufacturing, particularly fused deposition modelling (FDM). The recent large-scale applications of 3D-printed ABS require stable mechanical properties than ever needed. However, thermochemical scission of butadiene bonds is one of the contemporary challenges affecting the overall ABS stability. In this regard, literature reports melt-blending of ABS with different polymers with high thermal resistance. However, the comparison for the effects of different polymers on tensile strength of 3D-printed ABS blends was not yet reported. Furthermore, the cumulative studies comprising both blended polymers and in-process thermal variables for FDM were not yet presented as well. This research, for the first time, presents the statistical comparison of tensile properties for the added polymers and in-process thermal variables (printing temperature and build surface temperature). The research presents Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) to explain the thermochemical reasons behind achieved mechanical properties. Overall, ABS blend with PP shows high tensile strength (≈31 MPa) at different combinations of in-process parameters. Furthermore, some commonalities among both blends are noted, i.e., the tensile strength improves with increase of surface (bed) and printing temperature. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

11 pages, 308 KiB

Open AccessArticle

On Structure of Infinite B*-Matrices over Normed Fields

by Sergey Victor Ludkowski

Inventions 2021, 6(4), 92; https://doi.org/10.3390/inventions6040092 - 22 Nov 2021

Cited by 1 | Viewed by 1840

Abstract

This article is devoted to the investigation of infinite B*-matrices and linear operators over normed fields. Their structure is studied in the paper. Ideals and centers of the corresponding to them B*-algebras are scrutinized. Full article

(This article belongs to the Section Inventions and Innovation in Design, Modeling and Computing Methods)

15 pages, 5199 KiB

Open AccessArticle

Design of Small Unmanned Surface Vehicle with Autonomous Navigation System

by Georgii Kolev, Seyed Nima Tayarani Bathaie, Vyacheslav Rybin, Maksim Kulagin and Timur Karimov

Inventions 2021, 6(4), 91; https://doi.org/10.3390/inventions6040091 - 22 Nov 2021

Cited by 6 | Viewed by 5787

Abstract

Maintaining ecosystems is one of the current leading public concerns. Some of the pressing problems that threaten water resources are pollution of water bodies with floating debris, illegal extraction of water resources, wear and tear of underwater communications. Therefore, the creation of special [...] Read more.

Maintaining ecosystems is one of the current leading public concerns. Some of the pressing problems that threaten water resources are pollution of water bodies with floating debris, illegal extraction of water resources, wear and tear of underwater communications. Therefore, the creation of special technical solutions is urgent. This paper reports a model-based design of an unmanned surface vehicle (USV), purposed to control and maintain the oxygen level and parameters such as acidity and the water temperature in rivers, lakes, inland waterways, and coastal waters. The developed USV navigation autopilot is described as a system with two inputs and one output. The autopilot selected is an adaptive controller based on the concept of proportional, integral, and derivative (PID). The autopilot is implemented on the STM32 microcontroller and allows precisely maintaining a given course, adjusting the speed and angle of rotation during wind drift and other influences. The new technique for sensor calibration and data acquisition is described. Simulation results are given, showing the performance of the autopilot algorithm in response to variations in the environment. The numerical experiments of the model have presented the result of confirming the sufficient correspondence between prototype characteristics and simulation results. Finally, thorough field trials were performed to verify the reliability and precision of the proposed solutions. The developed unmanned surface vehicle can be used for environmental monitoring (water sampling, hydrography, patrolling water areas). In turn, the solutions obtained will be suitable for the design of other USV of different sizes. Full article

(This article belongs to the Special Issue Quadrotor UAV with Advanced Applications)

► Show Figures

Figure 1

6 pages, 225 KiB

Open AccessArticle

To the Theory of Unsteady Thermal Conductivity Caused by the Hot Core of the Earth

by Sergey O. Gladkov

Inventions 2021, 6(4), 90; https://doi.org/10.3390/inventions6040090 - 19 Nov 2021

Viewed by 2085

Abstract

A solution is given to the spatial-temporary distribution of temperature in the volume of the Earth, due to the specified power of the thermal radiation of the hot core. An estimate is made of the maximum possible cooling time of the core. Full article

(This article belongs to the Special Issue Thermodynamic and Technical Analysis for Sustainability)

18 pages, 6713 KiB

Open AccessArticle

Efficient Model for Accurate Assessment of Frequency Support by Large Populations of Plug-in Electric Vehicles

by Michail Dakanalis and Fotios D. Kanellos

Inventions 2021, 6(4), 89; https://doi.org/10.3390/inventions6040089 - 18 Nov 2021

Cited by 4 | Viewed by 2730

Abstract

In recent years, plug-in electric vehicles (PEVs) have gained immense popularity and are on a trajectory of constant growth. As a result, power systems are confronted with new issues and challenges, threatening their safety and reliability. PEVs are currently treated as simple loads [...] Read more.

In recent years, plug-in electric vehicles (PEVs) have gained immense popularity and are on a trajectory of constant growth. As a result, power systems are confronted with new issues and challenges, threatening their safety and reliability. PEVs are currently treated as simple loads due to their low penetration. However, as their numbers are growing, PEVs could potentially be exploited as distributed energy storage devices providing ancillary services to the network. Batteries used in PEVs are developed to deliver instantaneously active power, making them an excellent solution for system frequency support. This paper proposes a detailed dynamic model that is able to simulate frequency support capability from a large number of PEVs, using an innovative aggregate battery model that takes into account the most significant constraints at PEV and aggregate battery levels. The cost optimization algorithm, which is the most time-consuming process of the problem, is executed only at the aggregate battery level, thereby reducing the computational requirements of the model without compromising the obtained accuracy. The proposed method is applied to the power system of Crete exploiting detailed statistical data of EV mobility. It is proven that PEVs can effectively support power system frequency fluctuations without any significant deviation from their optimal operation. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

11 pages, 3408 KiB

Open AccessArticle

A New Maximum Power Point Tracking Technique for Thermoelectric Generator Modules

by Mohammed A. Qasim, Naseer T. Alwan, Seepana PraveenKumar, Vladimir I. Velkin and Ephraim Bonah Agyekum

Inventions 2021, 6(4), 88; https://doi.org/10.3390/inventions6040088 - 18 Nov 2021

Cited by 27 | Viewed by 3415

Abstract

Thermoelectric generators (TEGs) are devices that convert heat into electricity. This paper is about the design of a Maximum Power Point Tracking (MPPT) technique for a TEG module. The module is built using 204 TEGs connected in series. It is connected to the [...] Read more.

Thermoelectric generators (TEGs) are devices that convert heat into electricity. This paper is about the design of a Maximum Power Point Tracking (MPPT) technique for a TEG module. The module is built using 204 TEGs connected in series. It is connected to the load through a DC/DC boost converter. The MPPT technique used in this work is the Interval Type 2 Fuzzy Logic Controller (IT2FLC). To verify its performance, the IT2FLC is compared with a traditional Perturb and Observe (P&O) MPPT algorithm in the case of power and voltage response at steady state, load switching, and through various ranges of temperature differences (ΔT). The TEG module is modeled and the whole system is simulated successfully using MATLAB SIMULINK R2017a. Full article

(This article belongs to the Special Issue Automatic Control and System Theory and Advanced Applications)

► Show Figures

Figure 1

20 pages, 9448 KiB

Open AccessArticle

Proposed Smart Monitoring System for the Detection of Bee Swarming

by George Voudiotis, Sotirios Kontogiannis and Christos Pikridas

Inventions 2021, 6(4), 87; https://doi.org/10.3390/inventions6040087 - 17 Nov 2021

Cited by 17 | Viewed by 6075

Abstract

This paper presents a bee-condition-monitoring system incorporated with a deep-learning process to detect bee swarming. This system includes easy-to-use image acquisition and various end node approaches for either on-site or cloud-based mechanisms. This system also incorporates a new smart CNN engine called Swarm-engine [...] Read more.

This paper presents a bee-condition-monitoring system incorporated with a deep-learning process to detect bee swarming. This system includes easy-to-use image acquisition and various end node approaches for either on-site or cloud-based mechanisms. This system also incorporates a new smart CNN engine called Swarm-engine for detecting bees and the issue of notifications in cases of bee swarming conditions to the apiarists. First, this paper presents the authors’ proposed implementation system architecture and end node versions that put it to the test. Then, several pre-trained networks of the authors’ proposed CNN Swarm-engine were also validated to detect bee-clustering events that may lead to swarming. Finally, their accuracy and performance towards detection were evaluated using both cloud cores and embedded ARM devices on parts of the system’s different end-node implementations. Full article

(This article belongs to the Special Issue Low-Cost Inventions and Patents)

► Show Figures

Figure 1

11 pages, 3632 KiB

Open AccessArticle

Research and Development of Metrological Assurance Elements for Leeb Hardness Measurements

by Vladimir Syasko and Artem Nikazov

Inventions 2021, 6(4), 86; https://doi.org/10.3390/inventions6040086 - 17 Nov 2021

Cited by 3 | Viewed by 2605

Abstract

This article is devoted to contemporary topics of ensuring the uniformity of Leeb hardness measurements. The analysis of the physical principles of the Leeb hardness test is carried out, and the influence of the measuring transducer parameters on the measurement results is investigated. [...] Read more.

This article is devoted to contemporary topics of ensuring the uniformity of Leeb hardness measurements. The analysis of the physical principles of the Leeb hardness test is carried out, and the influence of the measuring transducer parameters on the measurement results is investigated. A four-level structure of the calibration hierarchy for the Leeb hardness scales is proposed, which ensures metrological traceability of hardness scales from the calibration reference machines (CRMs) to measuring instruments. A list of requirements for the 2nd grade CRM and the 2nd grade Leeb reference test blocks are formulated in accordance with the proposed calibration hierarchy draft and their values are calculated. A prototype was developed and a model of the 2nd grade Leeb hardness CRM and a set of Leeb reference test blocks were manufactured, as well as the compliance of their metrological characteristics with the requirements of the proposed calibration hierarchy draft and international standards was confirmed. The results of this work allow us to ensure the uniformity and reliability of the Leeb hardness measurements. Full article

(This article belongs to the Section Inventions and Innovation in Surface Science and Nanotechnology)

► Show Figures

Figure 1

16 pages, 4629 KiB

Open AccessArticle

Operation Safety of a 2-DoF Planar Mechanism for Arm Rehabilitation

by Marco Ceccarelli, Matteo Russo, Daniele Cafolla and Betsy D. M. Chaparro-Rico

Inventions 2021, 6(4), 85; https://doi.org/10.3390/inventions6040085 - 15 Nov 2021

Cited by 2 | Viewed by 3053

Abstract

The operation safety of rehabilitation devices must be addressed early in the development process and before being tested on people. In this paper, the operation safety of a 2-DoF (degrees of freedom) planar mechanism for arm rehabilitation is addressed. Then, the safety and [...] Read more.

The operation safety of rehabilitation devices must be addressed early in the development process and before being tested on people. In this paper, the operation safety of a 2-DoF (degrees of freedom) planar mechanism for arm rehabilitation is addressed. Then, the safety and efficiency of the device operation is assessed through the Transmission Index (TI) distribution in its workspace. Furthermore, the produced stresses on the human arm are assessed via the FEM (finite element method) when the rehabilitation device reaches five critical positions within its workspace. The TI distribution showed that the proposed design has a proper behaviour from a force transmission point of view, avoiding any singular configuration that might cause a control failure and subsequent risk for the user and supporting the user’s motion with a good efficiency throughout its operational workspace. The FEM analysis showed that Nurse operation is safe for the human arm since a negligible maximum stress of 6.55 × 10³ N/m² is achieved by the human arm when the device is located on the evaluated critical positions. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

17 pages, 11186 KiB

Open AccessArticle

HIGROTERM: An Open-Source and Low-Cost Temperature and Humidity Monitoring System for Laboratory Applications

by Renan Rocha Ribeiro, Elton Bauer and Rodrigo Lameiras

Inventions 2021, 6(4), 84; https://doi.org/10.3390/inventions6040084 - 15 Nov 2021

Cited by 4 | Viewed by 4295

Abstract

Low-cost electronics developed on easy-to-use prototyping platforms, such as Arduino, are becoming increasingly popular in various fields of science. This article presents an open-source and low-cost eight-channel data-logging system for temperature and humidity monitoring based on DHT22 (AM2302) sensors, named HIGROTERM. The system [...] Read more.

Low-cost electronics developed on easy-to-use prototyping platforms, such as Arduino, are becoming increasingly popular in various fields of science. This article presents an open-source and low-cost eight-channel data-logging system for temperature and humidity monitoring based on DHT22 (AM2302) sensors, named HIGROTERM. The system was designed to solve real needs of the Laboratory of Material Testing of the Department of Civil and Environmental Engineering at the University of Brasília. The system design, functionalities, hardware components, source code, bill of materials, assemblage and enclosure are thoroughly described to enable complete reproduction by the interested reader. The terminologies and instructions presented were simplified as much as possible to make it accessible to the greatest extent to researchers from different areas, especially those without electronics background. The data-acquisition system has an estimated total cost of USD 96.00, or USD 136.00 if eight sensor nodes are included, with a considerable margin for cost reduction. The authors expect that the HIGROTERM system may both be a valuable low-cost and customizable tool for the readers, as well a source of innovation and interest in low-cost electronics for real problem-solving in various fields of science. Full article

(This article belongs to the Special Issue Low-Cost Inventions and Patents)

► Show Figures

Figure 1

26 pages, 30520 KiB

Open AccessArticle

Design and Research Sowing Devices for Aerial Sowing of Forest Seeds with UAVs

by Mikhail Lysych, Leonid Bukhtoyarov and Denis Druchinin

Inventions 2021, 6(4), 83; https://doi.org/10.3390/inventions6040083 - 10 Nov 2021

Cited by 5 | Viewed by 9501

Abstract

Modern unmanned aerial vehicles (UAV) can be effectively used for aerial sowing of forests. A feature of aerial sowing is the possibility of rapid reforestation at low costs, which is extremely important in the current environmental situation. The purpose of this study is [...] Read more.

Modern unmanned aerial vehicles (UAV) can be effectively used for aerial sowing of forests. A feature of aerial sowing is the possibility of rapid reforestation at low costs, which is extremely important in the current environmental situation. The purpose of this study is to develop a set of sowing devices intended for use with UAVs. For this, the metering devices and seed distribution devices were analyzed, used on the UAV or having prospects for such use. The existing studies of metering devices, implemented by numerical methods, are analyzed. Further, the synthesis of eight different designs of sowing devices in the 3D CAD was carried out and their comparative assessment was completed in terms of mass and a set of technological parameters. Based on its results, a sowing device was selected that is most suitable for a specific given technology. Discrete Element Method (DEM) was used to simulate the workflow: imitation of loading of the sowing device, study of work in various modes, study of the process of impact interaction of seeds with the soil environment. The complex of developed sowing devices can provide sowing of almost any type of forest seeds within the framework of various technologies and soil climatic conditions. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

20 pages, 119435 KiB

Open AccessArticle

GD (Generative Design) Applied to a Plastics Recovery Drone (PRD) Using IDeS (Industrial Design Structure)

by Leonardo Frizziero, Alfredo Liverani, Giampiero Donnici, Enrico Conti, Beatrice Dello Preite, Umberto Lamanna, Christian Leon-Cardenas and Matteo Garulli

Inventions 2021, 6(4), 82; https://doi.org/10.3390/inventions6040082 - 5 Nov 2021

Cited by 4 | Viewed by 4183

Abstract

The evolution of innovative and systematic design methodologies over time has widened the design concept involvement from the product development phase, which also includes the production and start-up phases. Literature findings have presented to accomplish a Generative Design (GD) approach through the application [...] Read more.

The evolution of innovative and systematic design methodologies over time has widened the design concept involvement from the product development phase, which also includes the production and start-up phases. Literature findings have presented to accomplish a Generative Design (GD) approach through the application of an innovative method called Industrial Structure Design (IDeS), a systematic design method able to discover the customer’s needs and the fundamental technical solutions to obtain a good innovative product, involving the whole organization for this achievement. Nevertheless, there is a social demand for solutions to the dramatic and growing problem of marine pollution from plastic materials, encouraging the designers to conceive a new innovative drone for waste collection at sea. Therefore, this study aims to merge all the most advanced design technologies with IDeS in an integrated way, by generating a structure that can also be adopted to plan the organization of a production company. The approach is validated with the design of the Recovery Plastic Drone (RPD) obtained with the IDeS methodology, combining Design and Product development phases, leading to a better and innovative solution for the market. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

10 pages, 1323 KiB

Open AccessArticle

Remote Monitoring of Patient Respiration with Mask Attachment—A Pragmatic Solution for Medical Facilities

by Vivian Ci Ai Koh, Yi Yang Ang, Wee Ser and Rex Xiao Tan

Inventions 2021, 6(4), 81; https://doi.org/10.3390/inventions6040081 - 3 Nov 2021

Cited by 1 | Viewed by 3337

Abstract

Remote monitoring of vital signs in infectious patients minimizes the risks of viral transmissions to healthcare professionals. Donning face masks could reduce the risk of viral transmissions and is currently practiced in medical facilities. An acoustic-sensing device was attached to face masks to [...] Read more.

Remote monitoring of vital signs in infectious patients minimizes the risks of viral transmissions to healthcare professionals. Donning face masks could reduce the risk of viral transmissions and is currently practiced in medical facilities. An acoustic-sensing device was attached to face masks to assist medical facilities in remotely monitoring patients’ respiration rate and wheeze occurrence. Usability and functionality studies of the modified face mask were evaluated on 16 healthy participants. Participants were blindfolded throughout the data collection process. Respiratory rates of the participants were evaluated for one minute. The wheeze detection algorithm was assessed by playing 176 wheezes and 176 normal breaths through a foam mannequin. No discomfort was reported from the participants who used the modified mask. The mean error of respiratory rate was found to be 2.0 ± 1.3 breath per minute. The overall accuracy of the wheeze detection algorithm was 91.9%. The microphone sensor that was first designed to be chest-worn has been proven versatile to be adopted as a mask attachment. The current findings support and suggest the use of the proposed mask attachment in medical facilities. This application can be especially helpful in managing a sudden influx of patients in the face of a pandemic. Full article

(This article belongs to the Section Inventions and Innovation in Biotechnology and Materials)

► Show Figures

Figure 1

12 pages, 1039 KiB

Open AccessArticle

Kalman Filter Adaptation to Disturbances of the Observer’s Parameters

by Alexander A. Manin, Sergey V. Sokolov, Arthur I. Novikov, Marianna V. Polyakova, Dmitriy N. Demidov and Tatyana P. Novikova

Inventions 2021, 6(4), 80; https://doi.org/10.3390/inventions6040080 - 2 Nov 2021

Cited by 4 | Viewed by 3066

Abstract

Currently, one of the most effective algorithms for state estimation of stochastic systems is a Kalman filter. This filter provides an optimal root-mean-square error in state vector estimation only when the parameters of the dynamic system and its observer are precisely known. In [...] Read more.

Currently, one of the most effective algorithms for state estimation of stochastic systems is a Kalman filter. This filter provides an optimal root-mean-square error in state vector estimation only when the parameters of the dynamic system and its observer are precisely known. In real conditions, the observer’s parameters are often inaccurately known; moreover, they change randomly over time. This in turn leads to the divergence of the Kalman estimation process. The problem is currently being solved in a variety of ways. They include the use of interval observers, the use of an extended Kalman filter, the introduction of an additional evaluating observer by nonlinear programming methods, robust scaling of the observer’s transmission coefficient, etc. At the same time, it should be borne in mind that, firstly, all of the above ways are focused on application in specific technical systems and complexes, and secondly, they fundamentally do not allow estimating errors in determining the parameters of the observer themselves in order to compensate them for further improving the accuracy and stability of the filtration process of the state vector. To solve this problem, this paper proposes the use of accurate observations that are irregularly received in a complex measuring system (for example, navigation) for adaptive evaluation of the observer’s true parameters of the stochastic system state vector. The development of the proposed algorithm is based on the analytical dependence of the Kalman estimate variation on the observer’s parameters disturbances obtained using the mathematical apparatus for the study of perturbed multidimensional dynamical systems. The developed algorithm for observer’s parameters adaptive estimation makes it possible to significantly increase the accuracy and stability of the stochastic estimation process as a whole in the time intervals between accurate observations, which is illustrated by the corresponding numerical example. Full article

(This article belongs to the Special Issue Automatic Control and System Theory and Advanced Applications)

► Show Figures

Figure 1

16 pages, 3747 KiB

Open AccessArticle

A Computer Vision System for Staff Gauge in River Flood Monitoring

by Luisiana Sabbatini, Lorenzo Palma, Alberto Belli, Francesca Sini and Paola Pierleoni

Inventions 2021, 6(4), 79; https://doi.org/10.3390/inventions6040079 - 2 Nov 2021

Cited by 22 | Viewed by 4418

Abstract

Rivers close to populated or strategically important areas can cause damages and safety risks to people in the event of a flood. Traditional river flood monitoring systems like radar and ultrasonic sensors may not be completely reliable and require frequent on-site human interventions [...] Read more.

Rivers close to populated or strategically important areas can cause damages and safety risks to people in the event of a flood. Traditional river flood monitoring systems like radar and ultrasonic sensors may not be completely reliable and require frequent on-site human interventions for calibration. This time-consuming and resource-intensive activity has attracted the attention of many researchers looking for highly reliable camera-based solutions. In this article we propose an automatic Computer Vision solution for river’s water-level monitoring, based on the processing of staff gauge images acquired by a V-IoT device. The solution is based on two modules. The first is implemented on the edge in order to avoid power consumption due to the transmission of poor quality frames, and another is implemented on the Cloud server, where the frames acquired and sent by the V-IoT device are processed for water level extraction. The proposed system was tested on sample images relating to more than a year of acquisitions at a river site. The first module of the proposed solution achieved excellent performances in discerning bad quality frames from good quality ones. The second module achieved very good results too, especially for what it concerns night frames. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

10 pages, 2625 KiB

Open AccessArticle

A Theoretical Terahertz Metamaterial Absorber Structure with a High Quality Factor Using Two Circular Ring Resonators for Biomedical Sensing

by Sagnik Banerjee, Uddipan Nath, Purba Dutta, Amitkumar Vidyakant Jha, Bhargav Appasani and Nicu Bizon

Inventions 2021, 6(4), 78; https://doi.org/10.3390/inventions6040078 - 2 Nov 2021

Cited by 36 | Viewed by 3574

Abstract

Metamaterial absorbers, on account of their inherent property of electromagnetic radiation absorption, have become a center of attraction for many researchers in recent times. This paper proposes a unique design of a terahertz metamaterial absorber that can be used to sense biomedical samples. [...] Read more.

Metamaterial absorbers, on account of their inherent property of electromagnetic radiation absorption, have become a center of attraction for many researchers in recent times. This paper proposes a unique design of a terahertz metamaterial absorber that can be used to sense biomedical samples. The proposed design consists of two identical circular ring resonators (CRRs) made of aluminum on top of a gallium arsenide (GaAs) substrate. On account of its high field confinement in the sensing regime, a near-to-perfect absorption rate of 99.50% is achieved at a frequency of 2.64 THz, along with a large quality factor (Q-Factor) of 44. The design is highly sensitive to the refractive index changes in the encompassing medium. Hence, the proposed absorber can be used as a refractive index sensor exhibiting a reasonable sensitivity of 1500 GHz/RIU and a figure of merit (FoM) of 25. The refractive index range has been varied in the range of 1.34 to 1.39. As many biomedical samples, including cancerous cells, reside within this range, the proposed sensor can be used for biomedical sensing applications. Full article

(This article belongs to the Section Inventions and Innovation in Biotechnology and Materials)

► Show Figures

Figure 1

13 pages, 2505 KiB

Open AccessArticle

Experimental Study of a Tilt Single Slope Solar Still Integrated with Aluminum Condensate Plate

by Naseer T. Alwan, Milia H. Majeed, Sergey E. Shcheklein, Obed M. Ali and Seepana PraveenKumar

Inventions 2021, 6(4), 77; https://doi.org/10.3390/inventions6040077 - 1 Nov 2021

Cited by 10 | Viewed by 3507

Abstract

The low freshwater productivity of a conventional solar still is considered a challenge for researchers due to the high temperature of the glass cover or basin water depth. In current work, a newly designed solar still was suggested according to the climatic conditions [...] Read more.

The low freshwater productivity of a conventional solar still is considered a challenge for researchers due to the high temperature of the glass cover or basin water depth. In current work, a newly designed solar still was suggested according to the climatic conditions of Yekaterinburg/Russia, which included an enhanced condensation and evaporation process by spraying a thin water film on a hot absorber plate and then passing the generated water vapor by free convection over the aluminum plate (low temperature). The distillation system under study was tested during July 2020 and 29 July was chosen as a typical day from 08:00 a.m. to 8:00 p.m. The results showed that the largest amount of water vapor condenses on the aluminum plate (about 46%), and the rest condenses on the glass cover. This means that the aluminum plate effectively improved productivity due to the flow of humid air naturally (free convection) on the aluminum plate (its surface temperature was lower than that of the glass cover). The cost analytical calculations showed that the cost of producing one liter of distilled water from the suggested solar still was 0.063$. Full article

(This article belongs to the Special Issue Thermodynamic and Technical Analysis for Sustainability)

► Show Figures

Figure 1

20 pages, 8208 KiB

Open AccessArticle

Adaptive Control for Multi-Shaft with Web Materials Linkage Systems

by Van Trong Dang, Duc Thinh Le, Van-Anh Nguyen-Thi, Danh Huy Nguyen, Thi Ly Tong, Duy Dinh Nguyen and Tung Lam Nguyen

Inventions 2021, 6(4), 76; https://doi.org/10.3390/inventions6040076 - 29 Oct 2021

Cited by 13 | Viewed by 2727

Abstract

In this paper, a fuzzy disturbance observer and a high-gain disturbance observer based on a variable structure controller are applied to deal with imprecise multi-shaft with web materials linkage systems taking into account the variation of the moment of inertia. Specifically, a high-gain [...] Read more.

In this paper, a fuzzy disturbance observer and a high-gain disturbance observer based on a variable structure controller are applied to deal with imprecise multi-shaft with web materials linkage systems taking into account the variation of the moment of inertia. Specifically, a high-gain disturbance observer and an adaptive fuzzy algorithm are separately applied to estimate system uncertainties and external disturbances. The high-gain disturbance observer is designed with auxiliary variables to avoid the amplification of the measurement disturbance, and the fuzzy disturbance observer has the advantage that it does not depend on model information. The convergence properties of the tracking error are analytically proven using Lyapunov’s theory. The obtained numerical results demonstrate the validity and the adaptive performance of the proposed control law in case the system is exposed to uncertainties and disturbances. Important remarks on the design process and performance benchmarks of the two observers are also demonstrated. Full article

(This article belongs to the Section Inventions and Innovation in Design, Modeling and Computing Methods)

► Show Figures

Figure 1

29 pages, 7949 KiB

Open AccessArticle

A Novel 2-D Point Absorber Numerical Modelling Method

by Gianmaria Giannini, Sandy Day, Paulo Rosa-Santos and Francisco Taveira-Pinto

Inventions 2021, 6(4), 75; https://doi.org/10.3390/inventions6040075 - 29 Oct 2021

Cited by 3 | Viewed by 2751

Abstract

Despite several wave energy converters (WECs) having been developed to present, no particular concept has emerged yet. The existing inventions vary significantly in terms of the operation principle and complexity of WECs. The tethered point absorbers (PAs) are among the most known devices [...] Read more.

Despite several wave energy converters (WECs) having been developed to present, no particular concept has emerged yet. The existing inventions vary significantly in terms of the operation principle and complexity of WECs. The tethered point absorbers (PAs) are among the most known devices that, thanks to their simplicity, appear to be cost-effective and reliable for offshore installation. These devices need to be advanced further and, therefore, new tailored modelling methods are required. Numerical modelling of this type of WEC has been done mainly in one degree of freedom. Existing methods for multi-degrees of freedom analysis lack pragmatism and accuracy. Nevertheless, modelling of multiple degrees of freedom is necessary for correct analysis of the device dynamic response, wave loads and device performance. Therefore, an innovative numerical method for two degrees of freedom analysis of PA WECs, which permits precisely modelling the dynamics of PA for surge and heave motions, is introduced in this paper. The new method allows assessing, in the time-domain, the dynamic response of tethered PAs using regular and irregular sea states. The novel numerical model is explained, proved and empirically validated. Full article

(This article belongs to the Special Issue Marine Renewable Energy, an Important Resource Towards a Low Carbon Future)

► Show Figures

Figure 1

19 pages, 4735 KiB

Open AccessArticle

Analysis Technology and Cathodic Protection for Hull Structures of Ships and Floating Facilities

by Vadim Kramar, Anna Rodkina, Olga Ivanova, Sergei Chernyi and Anton Zinchenko

Inventions 2021, 6(4), 74; https://doi.org/10.3390/inventions6040074 - 28 Oct 2021

Cited by 9 | Viewed by 2933

Abstract

Studies overviewed in the paper have yielded a number of new scientific results including the following: suggested is a technique for conducting experimental investigations of electrochemical characteristics of hull structures of ships and floating facilities on the juvenile surface under cathodic polarization in [...] Read more.

Studies overviewed in the paper have yielded a number of new scientific results including the following: suggested is a technique for conducting experimental investigations of electrochemical characteristics of hull structures of ships and floating facilities on the juvenile surface under cathodic polarization in a test seawater solution with the use of the test facility developed for investigating electrochemical characteristics of hull structures of ships and floating facilities on the juvenile surface under cathodic polarization; obtained are the results of laboratory experiments on various shipbuilding steels without surface oxide films in test seawater solutions with a widely ranging salinity spectrum; developed is a neural network-based technique for predicting the protection potential of ships and floating facilities from local corrosion mechanical damages; developed is an algorithm for obtaining the protective potential for hull structures of ships and floating facilities; suggested is a method of protecting hull structures of ships and floating facilities by means of cathodic polarization from local corrosion mechanical damages at the potential of the uncharged surface on the juvenile surface of steel; revealed are beneficial effects of using cathodic polarization by impressed current at the potential of the uncharged surface on the juvenile surface of steel which allow the prolongation of the service life of hull structures of ships and floating facilities. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

21 pages, 47564 KiB

Open AccessArticle

Impact of Electroosmosis and Wall Properties in Modelling Peristaltic Mechanism of a Jeffrey Liquid through a Microchannel with Variable Fluid Properties

by Choudhari Rajashekhar, Fateh Mebarek-Oudina, Ioannis E. Sarris, Hanumesh Vaidya, Kerehalli V. Prasad, Gudekote Manjunatha and Hadimane Balachandra

Inventions 2021, 6(4), 73; https://doi.org/10.3390/inventions6040073 - 28 Oct 2021

Cited by 16 | Viewed by 2798

Abstract

The current work emphasizes the modelling of the electroosmosis-modulated peristaltic flow of Jeffery liquid. Such flows emerge in understanding the movement of biological fluids in a microchannel, such as in targeted drug delivery and blood flow through micro arteries. The non-Newtonian fluid flows [...] Read more.

The current work emphasizes the modelling of the electroosmosis-modulated peristaltic flow of Jeffery liquid. Such flows emerge in understanding the movement of biological fluids in a microchannel, such as in targeted drug delivery and blood flow through micro arteries. The non-Newtonian fluid flows inside a non-uniform cross-section and an inclined microchannel. The effects of wall properties and variable fluid properties are considered. The long wavelength and small Re number approximations are assumed to simplify the governing equations. Debye-Hückel linearization is also utilized. The nonlinear governing equations are solved by utilizing the perturbation technique. MATLAB is used for the solution, velocity, temperature, skin friction, coefficient heat transport, concentration, shear wood number, and streamlines expressions. The obtained result in optimal electroosmotic velocity (or Helmholtz-Smoluchowski velocity) increases from −1 to 6; the axial circulation has substantial momentum. For larger optimal electroosmotic velocity, a subsequent boost in an axial electric field causes a significant deceleration. Further, the study helps biomedical engineers to create biomicrofluidics devices that may aid in carrying biological fluids. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

14 pages, 4580 KiB

Open AccessArticle

Study of Resistance to Disturbances of the Main Types of Communication Systems on Board Military Ships Used during Interception or Search and Rescue Missions

by Vasile Solcanu, Marian Gaiceanu and Georgiana Rosu

Inventions 2021, 6(4), 72; https://doi.org/10.3390/inventions6040072 - 27 Oct 2021

Cited by 3 | Viewed by 2928

Abstract

In addition to combat missions, military ships often participate in search-and-rescue missions or interception of ships with refugees or migrants. The communication systems and modes of work that may be used during these missions will be in accordance with the International Convention for [...] Read more.

In addition to combat missions, military ships often participate in search-and-rescue missions or interception of ships with refugees or migrants. The communication systems and modes of work that may be used during these missions will be in accordance with the International Convention for the Safety of Life at Sea (SOLAS). This paper aims to demonstrate by theoretical methods (analytical and numerical) the noise stability of communication systems using analog modulation in high-noise conditions, characteristic of the marine environment. The stability of analog systems employing amplitude (AM), frequency (FM), and phase (PM) modulations is investigated. The analyzed systems are currently under use in distress maritime communications. Full article

(This article belongs to the Special Issue Perspectives and Challenges in Doctoral Research—Selected Papers from the 9th Edition of the Scientific Conference of the Doctoral Schools from the “Dunărea de Jos” University of Galaţi)

► Show Figures

Figure 1

20 pages, 3654 KiB

Open AccessArticle

Parametric Open Source Cold-Frame Agrivoltaic Systems

by Joshua M. Pearce

Inventions 2021, 6(4), 71; https://doi.org/10.3390/inventions6040071 - 26 Oct 2021

Cited by 12 | Viewed by 3898

Abstract

There is an intense need to optimize agrivoltaic systems. This article describes the invention of a new testing system: the parametric open source cold-frame agrivoltaic system (POSCAS). POSCAS is an adapted gardening cold-frame used in cold climates as it acts as a small [...] Read more.

There is an intense need to optimize agrivoltaic systems. This article describes the invention of a new testing system: the parametric open source cold-frame agrivoltaic system (POSCAS). POSCAS is an adapted gardening cold-frame used in cold climates as it acts as a small greenhouse for agricultural production. POSCAS is designed to test partially transparent solar photovoltaic (PV) modules targeting the agrivoltaic market. It can both function as a traditional cold frame, but it can also be automated to function as a full-service greenhouse. The integrated PV module roof can be used to power the controls or it can be attached to a microinverter to produce power. POSCAS can be placed in an experimental array for testing agricultural and power production. It can be easily adapted for any type of partially transparent PV module. An array of POSCAS systems allows for the testing of agrivoltaic impacts from the percent transparency of the modules by varying the thickness of a thin film PV material or the density of silicon-based cells, and various forms of optical enhancement, anti-reflection coatings and solar light spectral shifting materials in the back sheet. All agrivoltaic variables can be customized to identify ideal PV designs for a given agricultural crop. Full article

(This article belongs to the Section Inventions and Innovation in Energy and Thermal/Fluidic Science)

► Show Figures

Figure 1

16 pages, 2844 KiB

Open AccessArticle

Binary and Multiclass Text Classification by Means of Separable Convolutional Neural Network

by Elena Solovyeva and Ali Abdullah

Inventions 2021, 6(4), 70; https://doi.org/10.3390/inventions6040070 - 19 Oct 2021

Cited by 5 | Viewed by 2894

Abstract

In this paper, the structure of a separable convolutional neural network that consists of an embedding layer, separable convolutional layers, convolutional layer and global average pooling is represented for binary and multiclass text classifications. The advantage of the proposed structure is the absence [...] Read more.

In this paper, the structure of a separable convolutional neural network that consists of an embedding layer, separable convolutional layers, convolutional layer and global average pooling is represented for binary and multiclass text classifications. The advantage of the proposed structure is the absence of multiple fully connected layers, which is used to increase the classification accuracy but raises the computational cost. The combination of low-cost separable convolutional layers and a convolutional layer is proposed to gain high accuracy and, simultaneously, to reduce the complexity of neural classifiers. Advantages are demonstrated at binary and multiclass classifications of written texts by means of the proposed networks under the sigmoid and Softmax activation functions in convolutional layer. At binary and multiclass classifications, the accuracy obtained by separable convolutional neural networks is higher in comparison with some investigated types of recurrent neural networks and fully connected networks. Full article

(This article belongs to the Collection Feature Innovation Papers)

► Show Figures

Figure 1

21 pages, 3440 KiB

Open AccessArticle

Experimental Study on Performance Enhancement of a Photovoltaic Module Using a Combination of Phase Change Material and Aluminum Fins—Exergy, Energy and Economic (3E) Analysis

by Ephraim Bonah Agyekum, Seepana PraveenKumar, Naseer T. Alwan, Vladimir Ivanovich Velkin and Tomiwa Sunday Adebayo

Inventions 2021, 6(4), 69; https://doi.org/10.3390/inventions6040069 - 18 Oct 2021

Cited by 34 | Viewed by 3255

Abstract

The electrical performance of a photovoltaic (PV) module is hugely affected by its temperature. This study proposed a passive cooling mechanism for the cooling of a PV panel. The proposed cooling system is made up of a combination of aluminum fins and paraffin [...] Read more.

The electrical performance of a photovoltaic (PV) module is hugely affected by its temperature. This study proposed a passive cooling mechanism for the cooling of a PV panel. The proposed cooling system is made up of a combination of aluminum fins and paraffin wax integrated at the PV panel’s rear side. The average temperature for the cooled panel for the entire period of the experiment is 36.62 °C against 48.75 °C for the referenced PV module. This represents an average reduction of 12.13 °C for the cooled panel. The average power for the cooled panel is 12.19 W against 10.95 W for the referenced module which is 11.33% improvement. The electrical efficiencies for the cooled panel and the referenced modules are 14.30% and 13.60%, respectively, representing an improvement of 5.15% in the electrical efficiency. The cooled solar PV module had an average exergy efficiency of 7.99% compared to 5.61% for the referenced module. In terms of the economics, the results from the computations show that LCOE of the cooled panel can range between 0.198 and 0.603 $/kWh, while that of the referenced module ranges from 0.221–0.671 $/kWh depending on the number of days it operates. Full article

(This article belongs to the Special Issue Thermodynamic and Technical Analysis for Sustainability)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Inventions, Volume 6, Issue 4 (December 2021) – 39 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI