Unwanted hole in metal sheet that use for vehicle body or structure is proved dangerous situation.
To prevent disaster this hole needs to be found before its installation, or other wise it will be time and
money consuming once its found when already finished installation. Therefore, an inspection using sensor
for metal sheet is recommended to prevent this problem. In this paper, we proposed a new sensor using
radio wave propagation to detect holes in metal sheet. We propose to use RSSI methods to detect hole
based on electromagnetic wave propagation signal strength. Using this method we success to detect
8 mm hole diameter in metal sheet with 1mm thickness. Using this method, we transmit electromagnetic
wave energy at about 20 dBm, and we receive with average -27.53 dBm for iron sheet and -23.13 dBm for
aluminum sheet.
Fabrication and characterization of printed zinc batteriesjournalBEEI
Zinc batteries are a more sustainable alternative to lithium-ion batteries due to its components being highly recyclable. With the improvements in the screen printing technology, high quality devices can be printed with at high throughput and precision at a lower cost compared to those manufactured using lithographic techniques. In this paper we describe the fabrication and characterization of printed zinc batteries. Different binder materials such as polyvinyl pyrrolidone (PVP) and polyvinyl butyral (PVB), were used to fabricate the electrodes. The electrodes were first evaluated using three-electrode cyclic voltammetry, x-ray diffraction (XRD), and scanning electron microscopy before being fully assembled and tested using charge-discharge test and two-electrode cyclic voltammetry. The results show that the printed ZnO electrode with PVB as binder performed better than PVP-based ZnO. The XRD data prove that the electro-active materials were successfully transferred to the sample. However, based on the evaluation, the results show that the cathode electrode was dominated by the silver instead of Ni(OH)2, which leads the sample to behave like a silver-zinc battery instead of a nickel-zinc battery. Nevertheless, the printed zinc battery electrodes were successfully evaluated, and more current collector materials for cathode should be explored for printed nickel-zinc batteries.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A Study of Micro–EDM on Silicon Nitride Using Electrode Materialsdrboon
This research proposes Cu, CuW and AgW for electrode materials for micro-electro-discharge machining (micro-EDM), which are produced with block electrode on insulating Si3N4. With these electrodes, some trials were evaluated considering the EDM conditions. The machining properties were estimated by the removal rate and tool wear ratio. The same phenomena are applied at the micron level for micro machining. The conductive layer was investigated on the micro-hole. This study aimed at the minimum of discharge energy to generate the conductive layer resulting to success micro-EDM on insulating ceramics.
Fabrication and characterization of printed zinc batteriesjournalBEEI
Zinc batteries are a more sustainable alternative to lithium-ion batteries due to its components being highly recyclable. With the improvements in the screen printing technology, high quality devices can be printed with at high throughput and precision at a lower cost compared to those manufactured using lithographic techniques. In this paper we describe the fabrication and characterization of printed zinc batteries. Different binder materials such as polyvinyl pyrrolidone (PVP) and polyvinyl butyral (PVB), were used to fabricate the electrodes. The electrodes were first evaluated using three-electrode cyclic voltammetry, x-ray diffraction (XRD), and scanning electron microscopy before being fully assembled and tested using charge-discharge test and two-electrode cyclic voltammetry. The results show that the printed ZnO electrode with PVB as binder performed better than PVP-based ZnO. The XRD data prove that the electro-active materials were successfully transferred to the sample. However, based on the evaluation, the results show that the cathode electrode was dominated by the silver instead of Ni(OH)2, which leads the sample to behave like a silver-zinc battery instead of a nickel-zinc battery. Nevertheless, the printed zinc battery electrodes were successfully evaluated, and more current collector materials for cathode should be explored for printed nickel-zinc batteries.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A Study of Micro–EDM on Silicon Nitride Using Electrode Materialsdrboon
This research proposes Cu, CuW and AgW for electrode materials for micro-electro-discharge machining (micro-EDM), which are produced with block electrode on insulating Si3N4. With these electrodes, some trials were evaluated considering the EDM conditions. The machining properties were estimated by the removal rate and tool wear ratio. The same phenomena are applied at the micron level for micro machining. The conductive layer was investigated on the micro-hole. This study aimed at the minimum of discharge energy to generate the conductive layer resulting to success micro-EDM on insulating ceramics.
Project Smart City ,Project AMRUT, Project Solar PV Power ,Muncipal Corporation , ProjectStreet Light LED,Project Traffic Light, Project out door CCTV,Project Variable Moving Display,all Architect,MEP,Electrical Consultants ,Project Engineering Department Electrical, Project Telecom and Broadband
TRANSPARENT ELECTRONICS
Abstract: Transparent electronics is an emerging science and technology field focused on producing ‘invisible’ electronic circuitry and opto-electronic devices.
Applications include consumer electronics, new energy sources, and transportation; for example, automobilewindshields could transmit visual information to the driver. Glass in almost any setting could also double as an electronic device, possibly improving security systems or offering transparent displays. In a similar vein, windows could be used to produce electrical power. Other civilian and military applications in this research field include realtime wearable displays.
As for conventional Si/III–V-based electronics, the basic device structure is based on semiconductor junctions and transistors. However, the device building block materials, the semiconductor, the electric contacts, and the ielectric/passivation layers, must now be transparent in the visible –a true challenge! Therefore, the first scientific goal of this technology must be to discover,understand, and implement transparent high-performance electronic materials. The second goal is their implementation and evaluation in transistor and circuit structures.
The electronics during the past 10 years, the classes of materials available for transparent electronics applications have grown dramatically. Historically, this area was dominated by transparent conducting oxides (oxide materials that are both electrically conductive and optically transparent) because of their wide use in antistatic coatings, touch display panels, solar cells, flat panel displays, heaters, defrosters, ‘smart windows’ and optical coatings. All these applications use transparent conductive oxides as passive electrical or optical coatings. The field of transparent conducting oxide (TCO) materials has been reviewed and many treatises on the topic are available. However, more recently there have been tremendous efforts to develop new active materials for functional transparent electronics. These new technologies will require new materials sets, in addition to the TCO component, including conducting, dielectric and semiconducting materials, as well as passive components for full device fabrication.
COMBINING OPTICAL TRANSPARENCY WITH ELECTRICAL CONDUCTIVITY
Transparent conductors are neither 100% optically transparent nor metallically conductive. From the band structure point of view, the combination of the two properties in the same material is contradictory: a transparent material is an insulator which possesses completely filled valence and empty conduction bands; whereas metallic conductivity appears when the Fermi level lies within a band with a large density of states to provide high carrier concentration. Efficient transparent conductors find their niche in a compromise between a sufficient transmission within the visible spectral range and a moderate but useful in practice electrical conductivity.
Organic electronics is an emerging field with an unimaginable future.I have included nutshell of applications and future scope in this field.Think it will be helpful for engineering aspirants.
Transparent electronics is an emerging science and technology field concentrates on producing ‘invisible’ electronics circuit and optoelectronics devices. The application contains consumer electronics such as automobile windshield, transparent solar panel, transparent display and real time wearable display. In the conventional Si/III-V based electronics, the structure is based on semiconductor junction & transistor. However, the basic building material for transparent electronic devices which is to be transparent and in visible range is a true challenge. Therefore, to understand and implement such technology there are two scientific goals, to have a material which are optically transparent and electrically conductive and to implement an invisible circuitry. Development of such invisible transparent electronic devices needs expertise together from pure and applied science, material science, chemistry, physics &electronic science.
Metro Rail Project ,Bullet Train Project Electrical ,Traction Power,BMS, Signal and Telecom,Station Building Upper and Under Ground ,EPC Companies,Electrical Contractor,Consultants
Review Study and Importance of Micro Electric Discharge Machiningsushil Choudhary
Micro EDM process is one of the micro- machining processes. It can be used to machine micro features and
makes a micro parts. There is a huge demand in the production of microstructures by a non-traditional method
which known as Micro-EDM. Micro-EDM process is based on the thermoelectric energy between the workpiece
and an electrode. Micro-EDM is a newly developed method to produce micro-parts which in the range of
50 μm -100 μm. Micro-EDM is an efficient machining process for the fabrication of a micro-metal hole with
various advantages resulting from its characteristics of non-contact and thermal process. A pulse discharges
occur in a small gap between the work piece and the electrode and at the same time removes the unwanted
material from the parent metal through the process of melting and vaporization. This paper describes the
importance, parameters, principle, difference between Macro and micro EDM, applications and advantages of μ-
EDM and discuss about the literature reviews based on performance measure in micro- EDMP process.
its a great presentation about transparent electronics, its easy to explain and i have selected only those slides which are of the basic level and very easy to explain, perfect for beginners.
In this research, we designed and implemented an advanced metal detector based on the Atmega328p microprocessor; it is used in the security field to prevent the entry of dangerous metal tools or explosives to places that require a high degree of safety such as schools, airports, universities and commercial malls. Where the mechanism of the electronic scheme of the detector was understood, including what it contains of active and passive electronic components, the microprocessor used how to program it and its technical specifications were identified. After that, we converted the electronic diagram into a printed circuit board (PCB) via easyada.com, And then print this circuit on special paper so that we can transfer it on the copper board, and a special solution was used to remove the copper residues from the board, after that holes were created and the electronic elements were soldered, Moving on to the software part, the Arduino Uno chip was used to act as an ISP programmer, through which the Atmaga328p controller was programmed using AVRDUDESS software, tested with a small coil with a diameter of 1.5cm. The detector gave excellent performance in detecting metal pieces such as copper, aluminum, iron and silver, as well as electrical wires in the walls, where the device screen shows the signal strength of the captured metal as well as the numerical symbol of the metal. It also discovered the presence of a sharp tool hidden in the mouth, shoes or inside the clothes, and the device achieved high performance In discovering metal parts and determining their properties, with an accuracy of 80%.
Study on the effect of the substrate material type and thickness on the perfo...TELKOMNIKA JOURNAL
This article presents a new design of a four-pole microstrip filtering antenna. The filtering antenna consists of a bandpass filter, which has four resonators integrated to a monopole patch antenna. The filtering antenna is designed with a relatively high bandwidth of about 1.22 GHz to satisfy a high-speed data transmission. Three types of dielectric substrate materials were used for the design of the filtering antenna, which is RT/Duroid 5880, RO3003, and FR-4. The simulation results of the filtering antenna design, which are established on the three different dielectric substrate materials, are done by using Computer Simulation Technology (CST) software. Comparison results of the filtering antenna that is established on the three different dielectric substrate materials are done at a fixed substrate height and different substrate heights. The filtering antenna is designed at a center frequency f0 = 2.412 GHz, which is suitable for WLAN applications.
Project Smart City ,Project AMRUT, Project Solar PV Power ,Muncipal Corporation , ProjectStreet Light LED,Project Traffic Light, Project out door CCTV,Project Variable Moving Display,all Architect,MEP,Electrical Consultants ,Project Engineering Department Electrical, Project Telecom and Broadband
TRANSPARENT ELECTRONICS
Abstract: Transparent electronics is an emerging science and technology field focused on producing ‘invisible’ electronic circuitry and opto-electronic devices.
Applications include consumer electronics, new energy sources, and transportation; for example, automobilewindshields could transmit visual information to the driver. Glass in almost any setting could also double as an electronic device, possibly improving security systems or offering transparent displays. In a similar vein, windows could be used to produce electrical power. Other civilian and military applications in this research field include realtime wearable displays.
As for conventional Si/III–V-based electronics, the basic device structure is based on semiconductor junctions and transistors. However, the device building block materials, the semiconductor, the electric contacts, and the ielectric/passivation layers, must now be transparent in the visible –a true challenge! Therefore, the first scientific goal of this technology must be to discover,understand, and implement transparent high-performance electronic materials. The second goal is their implementation and evaluation in transistor and circuit structures.
The electronics during the past 10 years, the classes of materials available for transparent electronics applications have grown dramatically. Historically, this area was dominated by transparent conducting oxides (oxide materials that are both electrically conductive and optically transparent) because of their wide use in antistatic coatings, touch display panels, solar cells, flat panel displays, heaters, defrosters, ‘smart windows’ and optical coatings. All these applications use transparent conductive oxides as passive electrical or optical coatings. The field of transparent conducting oxide (TCO) materials has been reviewed and many treatises on the topic are available. However, more recently there have been tremendous efforts to develop new active materials for functional transparent electronics. These new technologies will require new materials sets, in addition to the TCO component, including conducting, dielectric and semiconducting materials, as well as passive components for full device fabrication.
COMBINING OPTICAL TRANSPARENCY WITH ELECTRICAL CONDUCTIVITY
Transparent conductors are neither 100% optically transparent nor metallically conductive. From the band structure point of view, the combination of the two properties in the same material is contradictory: a transparent material is an insulator which possesses completely filled valence and empty conduction bands; whereas metallic conductivity appears when the Fermi level lies within a band with a large density of states to provide high carrier concentration. Efficient transparent conductors find their niche in a compromise between a sufficient transmission within the visible spectral range and a moderate but useful in practice electrical conductivity.
Organic electronics is an emerging field with an unimaginable future.I have included nutshell of applications and future scope in this field.Think it will be helpful for engineering aspirants.
Transparent electronics is an emerging science and technology field concentrates on producing ‘invisible’ electronics circuit and optoelectronics devices. The application contains consumer electronics such as automobile windshield, transparent solar panel, transparent display and real time wearable display. In the conventional Si/III-V based electronics, the structure is based on semiconductor junction & transistor. However, the basic building material for transparent electronic devices which is to be transparent and in visible range is a true challenge. Therefore, to understand and implement such technology there are two scientific goals, to have a material which are optically transparent and electrically conductive and to implement an invisible circuitry. Development of such invisible transparent electronic devices needs expertise together from pure and applied science, material science, chemistry, physics &electronic science.
Metro Rail Project ,Bullet Train Project Electrical ,Traction Power,BMS, Signal and Telecom,Station Building Upper and Under Ground ,EPC Companies,Electrical Contractor,Consultants
Review Study and Importance of Micro Electric Discharge Machiningsushil Choudhary
Micro EDM process is one of the micro- machining processes. It can be used to machine micro features and
makes a micro parts. There is a huge demand in the production of microstructures by a non-traditional method
which known as Micro-EDM. Micro-EDM process is based on the thermoelectric energy between the workpiece
and an electrode. Micro-EDM is a newly developed method to produce micro-parts which in the range of
50 μm -100 μm. Micro-EDM is an efficient machining process for the fabrication of a micro-metal hole with
various advantages resulting from its characteristics of non-contact and thermal process. A pulse discharges
occur in a small gap between the work piece and the electrode and at the same time removes the unwanted
material from the parent metal through the process of melting and vaporization. This paper describes the
importance, parameters, principle, difference between Macro and micro EDM, applications and advantages of μ-
EDM and discuss about the literature reviews based on performance measure in micro- EDMP process.
its a great presentation about transparent electronics, its easy to explain and i have selected only those slides which are of the basic level and very easy to explain, perfect for beginners.
In this research, we designed and implemented an advanced metal detector based on the Atmega328p microprocessor; it is used in the security field to prevent the entry of dangerous metal tools or explosives to places that require a high degree of safety such as schools, airports, universities and commercial malls. Where the mechanism of the electronic scheme of the detector was understood, including what it contains of active and passive electronic components, the microprocessor used how to program it and its technical specifications were identified. After that, we converted the electronic diagram into a printed circuit board (PCB) via easyada.com, And then print this circuit on special paper so that we can transfer it on the copper board, and a special solution was used to remove the copper residues from the board, after that holes were created and the electronic elements were soldered, Moving on to the software part, the Arduino Uno chip was used to act as an ISP programmer, through which the Atmaga328p controller was programmed using AVRDUDESS software, tested with a small coil with a diameter of 1.5cm. The detector gave excellent performance in detecting metal pieces such as copper, aluminum, iron and silver, as well as electrical wires in the walls, where the device screen shows the signal strength of the captured metal as well as the numerical symbol of the metal. It also discovered the presence of a sharp tool hidden in the mouth, shoes or inside the clothes, and the device achieved high performance In discovering metal parts and determining their properties, with an accuracy of 80%.
Study on the effect of the substrate material type and thickness on the perfo...TELKOMNIKA JOURNAL
This article presents a new design of a four-pole microstrip filtering antenna. The filtering antenna consists of a bandpass filter, which has four resonators integrated to a monopole patch antenna. The filtering antenna is designed with a relatively high bandwidth of about 1.22 GHz to satisfy a high-speed data transmission. Three types of dielectric substrate materials were used for the design of the filtering antenna, which is RT/Duroid 5880, RO3003, and FR-4. The simulation results of the filtering antenna design, which are established on the three different dielectric substrate materials, are done by using Computer Simulation Technology (CST) software. Comparison results of the filtering antenna that is established on the three different dielectric substrate materials are done at a fixed substrate height and different substrate heights. The filtering antenna is designed at a center frequency f0 = 2.412 GHz, which is suitable for WLAN applications.
This paper presents a highly efficient power transfer system based on a co-design of a class-E power amplifier (PA) and a pair of inductively coupled Helical coils for through-metal-wall power transfer. Power is transferred wirelessly through a 3.1-mm thick aluminum barrier without any physical penetration and contact. Measurement results show that the class-E PA achieves a peak power gain of 25.2 dB and a maximum collector efficiency of 57.3%, all at 200 Hz. The proposed system obtains a maximum power transfer efficiency of 9% and it can deliver 5 W power to the receiver side through the aluminum barrier.
Design and modeling of solenoid inductor integrated with FeNiCo in high frequ...TELKOMNIKA JOURNAL
In this work, the design and modeling of the solenoid inductor are discussed. The layout of integrated inductors with magnetic cores and their geometrical parameters are developed. The quality factor Q and inductance value L are derived from the S-parameters and plotted versus frequency. The effect of solenoid inductor geometry on inductance and quality factor are studied via simulation using MATLAB. The solenoid inductor geometry parameters considered are the turn’s number, the magnetic core length, the width of a magnetic core, the gap between turns, the magnetic core thickness, the coil thickness, and solenoid inductor oxide thickness. The performance of the proposed solenoid inductor integrated with FeNiCo is compared with other solenoid inductors.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Effect of beam current, weld speed and dissolution on mechnical and microstru...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Effect of beam current, weld speed and dissolution on mechnical and microstru...eSAT Journals
Abstract Electron beam welding has proved phenomenal in welding of components used in space because it uses a vacuum environment which eliminates substances like oxygen, nitrogen, and hydrogen. The main advantage of EBW is its ability to weld dissimilar materials and incorporate desirable properties in the assembly. It has high depth to width ratio and focuses exactly on the portion to be welded, thereby reducing the weld area, making it one of the most suitable welding processes. In this study, welding has been done on a circular heterogeneous component using an electron beam welding machine to determine the effect of beam current, speed of weld and dissolution on the bead geometry, hardness at the weld bead and the heat affected zone. This component is made up of AISI 304(Austenitic) and AISI 446 (Ferrite) stainless steel, both of which are widely used in space applications.
ANALISIS DESAIN SISTEM GRID PENTANAHAN PLTU BERAU KALIMANTAN TIMUR 2 X 7 MWSyamsirAbduh2
To be able to secure and safety the equipment and the workers who work in the power plant area Berau 2 x 7 MW, of course, required the earthing system design quality, reliable and efficient whereby the grounding grid resistance, voltage step and touch voltage according to the calculations contained in IEEE Std 80 -2000. This research will discuss the evaluation of system design with respect to the value of earthing resistance grounding grid, mesh voltage and step voltage. Evaluation parameters - parameters according to calculations published in IEEE Std 80-2000. Results from this study is the need for improvements to the design value of the voltage step and touch voltage is actually one - each 219.03 V and 383.29 V, which is greater than the voltage step and touch voltages are allowed each - amounting to 164.86 V for weight 50 kg; 223.13 V for weights 70 kg and 128.21 V to weight 50 kg; 173.53 V to 70 kg weight.
Analyzing the deformation of copper conductor from a fire impactTELKOMNIKA JOURNAL
Fire is an oxidation reaction of the three elements (fuel, oxygen, heat) that can result in loss of property, injury, even death. Electricity potential that may results on fire is the short circuit current that occurs on the equipments and electrical installation cables. The remaining wires at the first fire location are subject to fire damage and can cause electrical short circuit. The purpose of this study is to analyze the short-circuit electrical deformation of copper cable using SEM EDS and MICRO XRF instrument. Based on the study result, there is a dominant change of oxygen elements in single cable and fiber sample causing fire that is 35.96% and 21.24%, those values are higher than Oxygen on a burned short-circuited cable that is 19.54% and 12.1%. The microstructure of the cable that causes fire looks like irregular clumps whereas the burned cable looks like a clump of clumps.
Design of Integrated LC Filter Using Multilayer Flexible Ferrite Sheets iosrjce
Dielectric and magnetic materials were developed for use as integrated passive component design.
The integrated LC component to be investigated in this paper uses ferrite material which combines both
magnetic and dielectric properties. Because of this double property, the ferrite sheet will be used in this design
as magnetic core for the inductor and dielectric substrate for the capacitor. The fabrication is simplified by
using PCB inductor and adhesive flexible ferrite sheet. To evaluate the inductance, the capacitance including
the parasitic resistance, a fabricated prototype of the LC component was simulated and measured. It was
confirmed that simulated values were very close to the measured values and the integrated LC component
behaves as low-pass filter
ADVANCEMENT IN ULTRASONIC VIBRATION AND MAGNETIC FIELD ASSISTED MICROEDM PROC...IAEME Publication
Micro-machining of components has been emerged as a peak demand in the world
of micro-manufacturing. Micro-EDM is proved to be the most suitable for micro
drilling purposes. It is very essential to fabricate micro holes as well as features with
very high dimensional accuracy and precision. The major drawbacks in micro-EDM
processes are the low metal removal, tool wear and surface roughness. Researchers
have carried out several investigations to compensate the various machining problems
in the micro-EDM process. So, there evolves a need for development of more
sophisticated machining features in micro-EDM process combining with additional
techniques. This paper presents a brief review on the latest advancement in ultrasonic
vibration and magnetic field assisted techniques to improve machining efficiency and
surface qualities of machined features in micro-EDM process. Latest industrial
applications of micro-EDM have been presented
ADVANCEMENT IN ULTRASONIC VIBRATION AND MAGNETIC FIELD ASSISTED MICROEDM PROC...IAEME Publication
Micro-machining of components has been emerged as a peak demand in the world
of micro-manufacturing. Micro-EDM is proved to be the most suitable for micro
drilling purposes. It is very essential to fabricate micro holes as well as features with
very high dimensional accuracy and precision. The major drawbacks in micro-EDM
processes are the low metal removal, tool wear and surface roughness. Researchers
have carried out several investigations to compensate the various machining problems
in the micro-EDM process. So, there evolves a need for development of more
sophisticated machining features in micro-EDM process combining with additional
techniques. This paper presents a brief review on the latest advancement in ultrasonic
vibration and magnetic field assisted techniques to improve machining efficiency and
surface qualities of machined features in micro-EDM process. Latest industrial
applications of micro-EDM have been presented.
Amazon products reviews classification based on machine learning, deep learni...TELKOMNIKA JOURNAL
In recent times, the trend of online shopping through e-commerce stores and websites has grown to a huge extent. Whenever a product is purchased on an e-commerce platform, people leave their reviews about the product. These reviews are very helpful for the store owners and the product’s manufacturers for the betterment of their work process as well as product quality. An automated system is proposed in this work that operates on two datasets D1 and D2 obtained from Amazon. After certain preprocessing steps, N-gram and word embedding-based features are extracted using term frequency-inverse document frequency (TF-IDF), bag of words (BoW) and global vectors (GloVe), and Word2vec, respectively. Four machine learning (ML) models support vector machines (SVM), logistic regression (RF), logistic regression (LR), multinomial Naïve Bayes (MNB), two deep learning (DL) models convolutional neural network (CNN), long-short term memory (LSTM), and standalone bidirectional encoder representations (BERT) are used to classify reviews as either positive or negative. The results obtained by the standard ML, DL models and BERT are evaluated using certain performance evaluation measures. BERT turns out to be the best-performing model in the case of D1 with an accuracy of 90% on features derived by word embedding models while the CNN provides the best accuracy of 97% upon word embedding features in the case of D2. The proposed model shows better overall performance on D2 as compared to D1.
Design, simulation, and analysis of microstrip patch antenna for wireless app...TELKOMNIKA JOURNAL
In this study, a microstrip patch antenna that works at 3.6 GHz was built and tested to see how well it works. In this work, Rogers RT/Duroid 5880 has been used as the substrate material, with a dielectric permittivity of 2.2 and a thickness of 0.3451 mm; it serves as the base for the examined antenna. The computer simulation technology (CST) studio suite is utilized to show the recommended antenna design. The goal of this study was to get a more extensive transmission capacity, a lower voltage standing wave ratio (VSWR), and a lower return loss, but the main goal was to get a higher gain, directivity, and efficiency. After simulation, the return loss, gain, directivity, bandwidth, and efficiency of the supplied antenna are found to be -17.626 dB, 9.671 dBi, 9.924 dBi, 0.2 GHz, and 97.45%, respectively. Besides, the recreation uncovered that the transfer speed side-lobe level at phi was much better than those of the earlier works, at -28.8 dB, respectively. Thus, it makes a solid contender for remote innovation and more robust communication.
Design and simulation an optimal enhanced PI controller for congestion avoida...TELKOMNIKA JOURNAL
In this paper, snake optimization algorithm (SOA) is used to find the optimal gains of an enhanced controller for controlling congestion problem in computer networks. M-file and Simulink platform is adopted to evaluate the response of the active queue management (AQM) system, a comparison with two classical controllers is done, all tuned gains of controllers are obtained using SOA method and the fitness function chose to monitor the system performance is the integral time absolute error (ITAE). Transient analysis and robust analysis is used to show the proposed controller performance, two robustness tests are applied to the AQM system, one is done by varying the size of queue value in different period and the other test is done by changing the number of transmission control protocol (TCP) sessions with a value of ± 20% from its original value. The simulation results reflect a stable and robust behavior and best performance is appeared clearly to achieve the desired queue size without any noise or any transmission problems.
Improving the detection of intrusion in vehicular ad-hoc networks with modifi...TELKOMNIKA JOURNAL
Vehicular ad-hoc networks (VANETs) are wireless-equipped vehicles that form networks along the road. The security of this network has been a major challenge. The identity-based cryptosystem (IBC) previously used to secure the networks suffers from membership authentication security features. This paper focuses on improving the detection of intruders in VANETs with a modified identity-based cryptosystem (MIBC). The MIBC is developed using a non-singular elliptic curve with Lagrange interpolation. The public key of vehicles and roadside units on the network are derived from number plates and location identification numbers, respectively. Pseudo-identities are used to mask the real identity of users to preserve their privacy. The membership authentication mechanism ensures that only valid and authenticated members of the network are allowed to join the network. The performance of the MIBC is evaluated using intrusion detection ratio (IDR) and computation time (CT) and then validated with the existing IBC. The result obtained shows that the MIBC recorded an IDR of 99.3% against 94.3% obtained for the existing identity-based cryptosystem (EIBC) for 140 unregistered vehicles attempting to intrude on the network. The MIBC shows lower CT values of 1.17 ms against 1.70 ms for EIBC. The MIBC can be used to improve the security of VANETs.
Conceptual model of internet banking adoption with perceived risk and trust f...TELKOMNIKA JOURNAL
Understanding the primary factors of internet banking (IB) acceptance is critical for both banks and users; nevertheless, our knowledge of the role of users’ perceived risk and trust in IB adoption is limited. As a result, we develop a conceptual model by incorporating perceived risk and trust into the technology acceptance model (TAM) theory toward the IB. The proper research emphasized that the most essential component in explaining IB adoption behavior is behavioral intention to use IB adoption. TAM is helpful for figuring out how elements that affect IB adoption are connected to one another. According to previous literature on IB and the use of such technology in Iraq, one has to choose a theoretical foundation that may justify the acceptance of IB from the customer’s perspective. The conceptual model was therefore constructed using the TAM as a foundation. Furthermore, perceived risk and trust were added to the TAM dimensions as external factors. The key objective of this work was to extend the TAM to construct a conceptual model for IB adoption and to get sufficient theoretical support from the existing literature for the essential elements and their relationships in order to unearth new insights about factors responsible for IB adoption.
Efficient combined fuzzy logic and LMS algorithm for smart antennaTELKOMNIKA JOURNAL
The smart antennas are broadly used in wireless communication. The least mean square (LMS) algorithm is a procedure that is concerned in controlling the smart antenna pattern to accommodate specified requirements such as steering the beam toward the desired signal, in addition to placing the deep nulls in the direction of unwanted signals. The conventional LMS (C-LMS) has some drawbacks like slow convergence speed besides high steady state fluctuation error. To overcome these shortcomings, the present paper adopts an adaptive fuzzy control step size least mean square (FC-LMS) algorithm to adjust its step size. Computer simulation outcomes illustrate that the given model has fast convergence rate as well as low mean square error steady state.
Design and implementation of a LoRa-based system for warning of forest fireTELKOMNIKA JOURNAL
This paper presents the design and implementation of a forest fire monitoring and warning system based on long range (LoRa) technology, a novel ultra-low power consumption and long-range wireless communication technology for remote sensing applications. The proposed system includes a wireless sensor network that records environmental parameters such as temperature, humidity, wind speed, and carbon dioxide (CO2) concentration in the air, as well as taking infrared photos.The data collected at each sensor node will be transmitted to the gateway via LoRa wireless transmission. Data will be collected, processed, and uploaded to a cloud database at the gateway. An Android smartphone application that allows anyone to easily view the recorded data has been developed. When a fire is detected, the system will sound a siren and send a warning message to the responsible personnel, instructing them to take appropriate action. Experiments in Tram Chim Park, Vietnam, have been conducted to verify and evaluate the operation of the system.
Wavelet-based sensing technique in cognitive radio networkTELKOMNIKA JOURNAL
Cognitive radio is a smart radio that can change its transmitter parameter based on interaction with the environment in which it operates. The demand for frequency spectrum is growing due to a big data issue as many Internet of Things (IoT) devices are in the network. Based on previous research, most frequency spectrum was used, but some spectrums were not used, called spectrum hole. Energy detection is one of the spectrum sensing methods that has been frequently used since it is easy to use and does not require license users to have any prior signal understanding. But this technique is incapable of detecting at low signal-to-noise ratio (SNR) levels. Therefore, the wavelet-based sensing is proposed to overcome this issue and detect spectrum holes. The main objective of this work is to evaluate the performance of wavelet-based sensing and compare it with the energy detection technique. The findings show that the percentage of detection in wavelet-based sensing is 83% higher than energy detection performance. This result indicates that the wavelet-based sensing has higher precision in detection and the interference towards primary user can be decreased.
A novel compact dual-band bandstop filter with enhanced rejection bandsTELKOMNIKA JOURNAL
In this paper, we present the design of a new wide dual-band bandstop filter (DBBSF) using nonuniform transmission lines. The method used to design this filter is to replace conventional uniform transmission lines with nonuniform lines governed by a truncated Fourier series. Based on how impedances are profiled in the proposed DBBSF structure, the fractional bandwidths of the two 10 dB-down rejection bands are widened to 39.72% and 52.63%, respectively, and the physical size has been reduced compared to that of the filter with the uniform transmission lines. The results of the electromagnetic (EM) simulation support the obtained analytical response and show an improved frequency behavior.
Deep learning approach to DDoS attack with imbalanced data at the application...TELKOMNIKA JOURNAL
A distributed denial of service (DDoS) attack is where one or more computers attack or target a server computer, by flooding internet traffic to the server. As a result, the server cannot be accessed by legitimate users. A result of this attack causes enormous losses for a company because it can reduce the level of user trust, and reduce the company’s reputation to lose customers due to downtime. One of the services at the application layer that can be accessed by users is a web-based lightweight directory access protocol (LDAP) service that can provide safe and easy services to access directory applications. We used a deep learning approach to detect DDoS attacks on the CICDDoS 2019 dataset on a complex computer network at the application layer to get fast and accurate results for dealing with unbalanced data. Based on the results obtained, it is observed that DDoS attack detection using a deep learning approach on imbalanced data performs better when implemented using synthetic minority oversampling technique (SMOTE) method for binary classes. On the other hand, the proposed deep learning approach performs better for detecting DDoS attacks in multiclass when implemented using the adaptive synthetic (ADASYN) method.
The appearance of uncertainties and disturbances often effects the characteristics of either linear or nonlinear systems. Plus, the stabilization process may be deteriorated thus incurring a catastrophic effect to the system performance. As such, this manuscript addresses the concept of matching condition for the systems that are suffering from miss-match uncertainties and exogeneous disturbances. The perturbation towards the system at hand is assumed to be known and unbounded. To reach this outcome, uncertainties and their classifications are reviewed thoroughly. The structural matching condition is proposed and tabulated in the proposition 1. Two types of mathematical expressions are presented to distinguish the system with matched uncertainty and the system with miss-matched uncertainty. Lastly, two-dimensional numerical expressions are provided to practice the proposed proposition. The outcome shows that matching condition has the ability to change the system to a design-friendly model for asymptotic stabilization.
Implementation of FinFET technology based low power 4×4 Wallace tree multipli...TELKOMNIKA JOURNAL
Many systems, including digital signal processors, finite impulse response (FIR) filters, application-specific integrated circuits, and microprocessors, use multipliers. The demand for low power multipliers is gradually rising day by day in the current technological trend. In this study, we describe a 4×4 Wallace multiplier based on a carry select adder (CSA) that uses less power and has a better power delay product than existing multipliers. HSPICE tool at 16 nm technology is used to simulate the results. In comparison to the traditional CSA-based multiplier, which has a power consumption of 1.7 µW and power delay product (PDP) of 57.3 fJ, the results demonstrate that the Wallace multiplier design employing CSA with first zero finding logic (FZF) logic has the lowest power consumption of 1.4 µW and PDP of 27.5 fJ.
Evaluation of the weighted-overlap add model with massive MIMO in a 5G systemTELKOMNIKA JOURNAL
The flaw in 5G orthogonal frequency division multiplexing (OFDM) becomes apparent in high-speed situations. Because the doppler effect causes frequency shifts, the orthogonality of OFDM subcarriers is broken, lowering both their bit error rate (BER) and throughput output. As part of this research, we use a novel design that combines massive multiple input multiple output (MIMO) and weighted overlap and add (WOLA) to improve the performance of 5G systems. To determine which design is superior, throughput and BER are calculated for both the proposed design and OFDM. The results of the improved system show a massive improvement in performance ver the conventional system and significant improvements with massive MIMO, including the best throughput and BER. When compared to conventional systems, the improved system has a throughput that is around 22% higher and the best performance in terms of BER, but it still has around 25% less error than OFDM.
Reflector antenna design in different frequencies using frequency selective s...TELKOMNIKA JOURNAL
In this study, it is aimed to obtain two different asymmetric radiation patterns obtained from antennas in the shape of the cross-section of a parabolic reflector (fan blade type antennas) and antennas with cosecant-square radiation characteristics at two different frequencies from a single antenna. For this purpose, firstly, a fan blade type antenna design will be made, and then the reflective surface of this antenna will be completed to the shape of the reflective surface of the antenna with the cosecant-square radiation characteristic with the frequency selective surface designed to provide the characteristics suitable for the purpose. The frequency selective surface designed and it provides the perfect transmission as possible at 4 GHz operating frequency, while it will act as a band-quenching filter for electromagnetic waves at 5 GHz operating frequency and will be a reflective surface. Thanks to this frequency selective surface to be used as a reflective surface in the antenna, a fan blade type radiation characteristic at 4 GHz operating frequency will be obtained, while a cosecant-square radiation characteristic at 5 GHz operating frequency will be obtained.
Reagentless iron detection in water based on unclad fiber optical sensorTELKOMNIKA JOURNAL
A simple and low-cost fiber based optical sensor for iron detection is demonstrated in this paper. The sensor head consist of an unclad optical fiber with the unclad length of 1 cm and it has a straight structure. Results obtained shows a linear relationship between the output light intensity and iron concentration, illustrating the functionality of this iron optical sensor. Based on the experimental results, the sensitivity and linearity are achieved at 0.0328/ppm and 0.9824 respectively at the wavelength of 690 nm. With the same wavelength, other performance parameters are also studied. Resolution and limit of detection (LOD) are found to be 0.3049 ppm and 0.0755 ppm correspondingly. This iron sensor is advantageous in that it does not require any reagent for detection, enabling it to be simpler and cost-effective in the implementation of the iron sensing.
Impact of CuS counter electrode calcination temperature on quantum dot sensit...TELKOMNIKA JOURNAL
In place of the commercial Pt electrode used in quantum sensitized solar cells, the low-cost CuS cathode is created using electrophoresis. High resolution scanning electron microscopy and X-ray diffraction were used to analyze the structure and morphology of structural cubic samples with diameters ranging from 40 nm to 200 nm. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 °C, 120 °C, 150 °C, and 180 °C under vacuum. The fluorine doped tin oxide (FTO)/CuS cathode electrode reached a maximum efficiency of 3.89% when it was calcined at 120 °C. Compared to other temperature combinations, CuS nanoparticles crystallize at 120 °C, which lowers resistance while increasing electron lifetime.
In place of the commercial Pt electrode used in quantum sensitized solar cells, the low-cost CuS cathode is created using electrophoresis. High resolution scanning electron microscopy and X-ray diffraction were used to analyze the structure and morphology of structural cubic samples with diameters ranging from 40 nm to 200 nm. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 °C, 120 °C, 150 °C, and 180 °C under vacuum. The fluorine doped tin oxide (FTO)/CuS cathode electrode reached a maximum efficiency of 3.89% when it was calcined at 120 °C. Compared to other temperature combinations, CuS nanoparticles crystallize at 120 °C, which lowers resistance while increasing electron lifetime.
A progressive learning for structural tolerance online sequential extreme lea...TELKOMNIKA JOURNAL
This article discusses the progressive learning for structural tolerance online sequential extreme learning machine (PSTOS-ELM). PSTOS-ELM can save robust accuracy while updating the new data and the new class data on the online training situation. The robustness accuracy arises from using the householder block exact QR decomposition recursive least squares (HBQRD-RLS) of the PSTOS-ELM. This method is suitable for applications that have data streaming and often have new class data. Our experiment compares the PSTOS-ELM accuracy and accuracy robustness while data is updating with the batch-extreme learning machine (ELM) and structural tolerance online sequential extreme learning machine (STOS-ELM) that both must retrain the data in a new class data case. The experimental results show that PSTOS-ELM has accuracy and robustness comparable to ELM and STOS-ELM while also can update new class data immediately.
Electroencephalography-based brain-computer interface using neural networksTELKOMNIKA JOURNAL
This study aimed to develop a brain-computer interface that can control an electric wheelchair using electroencephalography (EEG) signals. First, we used the Mind Wave Mobile 2 device to capture raw EEG signals from the surface of the scalp. The signals were transformed into the frequency domain using fast Fourier transform (FFT) and filtered to monitor changes in attention and relaxation. Next, we performed time and frequency domain analyses to identify features for five eye gestures: opened, closed, blink per second, double blink, and lookup. The base state was the opened-eyes gesture, and we compared the features of the remaining four action gestures to the base state to identify potential gestures. We then built a multilayer neural network to classify these features into five signals that control the wheelchair’s movement. Finally, we designed an experimental wheelchair system to test the effectiveness of the proposed approach. The results demonstrate that the EEG classification was highly accurate and computationally efficient. Moreover, the average performance of the brain-controlled wheelchair system was over 75% across different individuals, which suggests the feasibility of this approach.
Adaptive segmentation algorithm based on level set model in medical imagingTELKOMNIKA JOURNAL
For image segmentation, level set models are frequently employed. It offer best solution to overcome the main limitations of deformable parametric models. However, the challenge when applying those models in medical images stills deal with removing blurs in image edges which directly affects the edge indicator function, leads to not adaptively segmenting images and causes a wrong analysis of pathologies wich prevents to conclude a correct diagnosis. To overcome such issues, an effective process is suggested by simultaneously modelling and solving systems’ two-dimensional partial differential equations (PDE). The first PDE equation allows restoration using Euler’s equation similar to an anisotropic smoothing based on a regularized Perona and Malik filter that eliminates noise while preserving edge information in accordance with detected contours in the second equation that segments the image based on the first equation solutions. This approach allows developing a new algorithm which overcome the studied model drawbacks. Results of the proposed method give clear segments that can be applied to any application. Experiments on many medical images in particular blurry images with high information losses, demonstrate that the developed approach produces superior segmentation results in terms of quantity and quality compared to other models already presented in previeous works.
Automatic channel selection using shuffled frog leaping algorithm for EEG bas...TELKOMNIKA JOURNAL
Drug addiction is a complex neurobiological disorder that necessitates comprehensive treatment of both the body and mind. It is categorized as a brain disorder due to its impact on the brain. Various methods such as electroencephalography (EEG), functional magnetic resonance imaging (FMRI), and magnetoencephalography (MEG) can capture brain activities and structures. EEG signals provide valuable insights into neurological disorders, including drug addiction. Accurate classification of drug addiction from EEG signals relies on appropriate features and channel selection. Choosing the right EEG channels is essential to reduce computational costs and mitigate the risk of overfitting associated with using all available channels. To address the challenge of optimal channel selection in addiction detection from EEG signals, this work employs the shuffled frog leaping algorithm (SFLA). SFLA facilitates the selection of appropriate channels, leading to improved accuracy. Wavelet features extracted from the selected input channel signals are then analyzed using various machine learning classifiers to detect addiction. Experimental results indicate that after selecting features from the appropriate channels, classification accuracy significantly increased across all classifiers. Particularly, the multi-layer perceptron (MLP) classifier combined with SFLA demonstrated a remarkable accuracy improvement of 15.78% while reducing time complexity.
CHINA’S GEO-ECONOMIC OUTREACH IN CENTRAL ASIAN COUNTRIES AND FUTURE PROSPECTjpsjournal1
The rivalry between prominent international actors for dominance over Central Asia's hydrocarbon
reserves and the ancient silk trade route, along with China's diplomatic endeavours in the area, has been
referred to as the "New Great Game." This research centres on the power struggle, considering
geopolitical, geostrategic, and geoeconomic variables. Topics including trade, political hegemony, oil
politics, and conventional and nontraditional security are all explored and explained by the researcher.
Using Mackinder's Heartland, Spykman Rimland, and Hegemonic Stability theories, examines China's role
in Central Asia. This study adheres to the empirical epistemological method and has taken care of
objectivity. This study analyze primary and secondary research documents critically to elaborate role of
china’s geo economic outreach in central Asian countries and its future prospect. China is thriving in trade,
pipeline politics, and winning states, according to this study, thanks to important instruments like the
Shanghai Cooperation Organisation and the Belt and Road Economic Initiative. According to this study,
China is seeing significant success in commerce, pipeline politics, and gaining influence on other
governments. This success may be attributed to the effective utilisation of key tools such as the Shanghai
Cooperation Organisation and the Belt and Road Economic Initiative.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
Low power architecture of logic gates using adiabatic techniquesnooriasukmaningtyas
The growing significance of portable systems to limit power consumption in ultra-large-scale-integration chips of very high density, has recently led to rapid and inventive progresses in low-power design. The most effective technique is adiabatic logic circuit design in energy-efficient hardware. This paper presents two adiabatic approaches for the design of low power circuits, modified positive feedback adiabatic logic (modified PFAL) and the other is direct current diode based positive feedback adiabatic logic (DC-DB PFAL). Logic gates are the preliminary components in any digital circuit design. By improving the performance of basic gates, one can improvise the whole system performance. In this paper proposed circuit design of the low power architecture of OR/NOR, AND/NAND, and XOR/XNOR gates are presented using the said approaches and their results are analyzed for powerdissipation, delay, power-delay-product and rise time and compared with the other adiabatic techniques along with the conventional complementary metal oxide semiconductor (CMOS) designs reported in the literature. It has been found that the designs with DC-DB PFAL technique outperform with the percentage improvement of 65% for NOR gate and 7% for NAND gate and 34% for XNOR gate over the modified PFAL techniques at 10 MHz respectively.
6th International Conference on Machine Learning & Applications (CMLA 2024)ClaraZara1
6th International Conference on Machine Learning & Applications (CMLA 2024) will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications of on Machine Learning & Applications.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
2. ISSN: 1693-6930
TELKOMNIKA Vol. 17, No. 5, October 2019: 2481-2485
2482
Table 1. Matrix of Related Research
Publication Application Device
R. Zoughi & S. Kharkovsky [12]
Microwave and millimetre wave sensors for crack
detection
Waveguide Antenna
B. Zhou & J. Zhang [15] Potential Measurement in ECT System Capacitance Electrode
P. Lopato & M. Herbko [16]
Microwave Structural Health Monitoring Sensor for
Deformation Measurement of Bended Steel
Microstrip Antenna
M. Lisowski & T.Uhl [17]
Wireless passive RFID-based sensor for crack
detection
RFID Printed Sheet
This work
A Low Cost Electromagnetic Sensor for Detecting
Holes in Metallic Sheet
ESP8266
2. Measurement Method
The metallic sheet under test is located between the transmitter and receiver, as
illustrated in Figure 1. The transmitter generates the electromagnetic signal with the frequency
2.4 GHz, which is transmitted by the antenna and propagates towards the metallic sheet.
A receiver captures the electromagnetic signals penetrating through the hole. The received
power can reveal the dimension of the holes under certain calibration.
Figure 1. Measurement Method
The designed electromagnetic sensor consists of the transmitter and receiver block.
The transmitter generates an electromagnetic wave which we tag with “SSID Metal Check”.
The receiver catches the electromagnetic wave signal, and using Arduino IDE Serial Monitor
calculates the received signal strength. To keep the interference to the minimal level, we placed
the transmitter block inside a 0.5 mm thick metallic case and the receiver block on a plastic
case. The microcontroller Wemos (esp8266 based) is used as an electromagnetic wave signal
transmitter and also as receiver. The microcontroller Wemos is a popular IoT node, which is low
cost and has compact size. It is a programmable microcontroller with L106 32-bit RISC
microprocessor core based on the Tensilica Xtensa Diamond Standard 106 Micro running at
80 MHz. This microprocessor has also a WiFi capability with an integrated TR switch, balun,
LNA, power amplifier and matching network.
The microcontroller wemos is powered by Li-Po battery; the battery charger and boost
converter for recharging the battery and powering the entire system; see Figure 2.
The transmitter circuit consists of four blockes, microcontroller wemos (A), the battery (B),
battery charger and boost converter (C) and the on/off switch (D), as given in the left side of
Figure 2. For the transmitter it is essential to set the equivalent isotrop radiated power (EIRP) in
order to be able to provide detectable received level behind the hole. The EIRP of
the transmitter consists of the transmit power (PTX) and the gain of the transmitting
antenna (GTX):
𝐸𝐼𝑅𝑃 = 𝑃𝑇𝑋 + 𝐺 𝑇𝑋 (1)
PTX = transmit power (17dBm)
GTX = gain of the antenna (3 dBi)
3. TELKOMNIKA ISSN: 1693-6930
A low cost electromagnetic sensor for detecting holes in metallic sheet (Galang P. N. Hakim)
2483
The EIRP becomes 17 dBm + 3 dBi = 20 dBm or 100 mW.
Whereas as illustrated in the right side of Figure 2, the receiver is also composed of
microcontroller wemos (A), the battery (B), battery charger and boost converter (C) and the on/off
switch (D). The received power can be calculated by (2):
𝑃𝑅𝑋 = 𝐸𝐼𝑅𝑃 − 𝑃𝐿 ≥ 𝑃𝑅𝑋,𝑚𝑖𝑛 (2)
PRX = Received Power (dBm)
PL = Path loss (dB)
PRX,min = minimal received power/sensitivity of the receiver (-98 dBm)
(a) (b)
Figure 2. (a) Transmitter and (b) receiver circuitry
In path loss we include the geometrical power decrease, all possible disturbances along
the propagation path and the gain of the receiving antenna. By this occasion, the effect of
the hole in metallic sheets can be described in the penetration of the fields through the hole.
The additional loss due to the hole is calculated in a simple way by comparing the received
power in the presence of the hole to the case without the hole. As long as, the value of
the received power is higher than the minimal detectable received power, we can measure
meaningful received power.
Moreover, there is a shielding characteristics due to the presence of the holey
sheet [18], which can be quantified by its shielding effectiveness. For a circular hole in a
metallic sheet, a simple equation is available as given in [19]:
𝑆𝐸 = 20 log (
𝜆 𝑜
2𝑑
) (3)
𝜆 𝑜 is the wavelength in the free space and d is the diameter of the hole.
In this work, we can calculate the shielding effectiveness simply by taking the difference
between the received power without and with the holey sheets:
𝑆𝐸 = 𝑃𝑅𝑋,𝑊𝑖𝑡ℎ𝑜𝑢𝑡 − 𝑃𝑅𝑋,𝑤𝑖𝑡ℎ (4)
3. Metallic Sheets under Test
In this work, we use two different metal specimens; the aluminum sheet and iron sheet.
Aluminum is a strong and light weight metal that can be found in everyday life such as food
wrapping, furniture, panel [20] etc. More importantly, aluminum is used in most aircraft [21], use
for shielding against lightning strike [22], also because its metal feature provides durability
against weather (corrosion resistant) [23] and has good thermal conductivity [24]. Meanwhile,
the iron can easily be found in a heavy duty application such as bridges [25], roads, and others.
In this experiment, we use iron and aluminum metal sheets with 1 mm thickness and
the dimension 10 cm x 15 cm. Each aluminum and iron metal sheet we built consist of a hole
with diameters of 2 mm, 4 mm, 6 mm and 8 mm, as given in Figure 3.
4. ISSN: 1693-6930
TELKOMNIKA Vol. 17, No. 5, October 2019: 2481-2485
2484
4. Measurement
A real time measurement is carried out to validate whether this sensor can detect a hole
in the metal sheet. In order to do that, at first we are going to measure the received power
without metal sheet. This measurement becomes a basis for calibration purposes for other
measurements. Any variation of the received power means disturbances in the propagation
path, which in this work is a metallic sheet with a hole with different diameter. Table 2 shows
the measured received signal strength for free space condition (without metal) and for the case
metallic sheets with different hole diameters. Based on the measured received power in
Table 2, the shielding effectiveness of holey iron and aluminum sheet is calculated with (4), and
for comparison purposes we use also the analytic equation in (3). The results are given
in Figure 4.
Figure 4 reveals that iron shows bigger shielding effectiveness than aluminum sheet
has. As the hole diameter increases, the value of shielding effectiveness decreases, as also
given by the simple analytical expression. We see the order of the measured values is the same
like given in the analytical approach.
Figure 3. Aluminum & iron metal sheet
specimens, from left to right (hole with a diameter
of 2 mm, 4 mm, 6 mm and 8 mm)
Figure 4. Shielding effectiveness of holey
iron and aluminum sheets
Table 2. RSSI Measurement obtained for several metallic sheets (values in dBm)
Spesimens
Without
Metal
Metal with hole, diameter
2 mm 4 mm 6 mm 8 mm
Iron -4.6 -33.1 -32.0 -34.1 -27.5
Aluminum -4.6 -27.3 -23.6 -26.1 -23.1
5. Conclusion
In this research we proposed a low cost electromagnetic wave based sensor for hole
detection in metal sheet. This sensor only cost about $37.8 dollar more cheaper compare with
RFID system based sensor. Using RSSI method to simplify the real time measurement, we
success to detect 8 mm hole in diameter in 1 mm thickness metal sheet. The transmitted signal
strength was 20 dBm and the received signal strength at average -27.53 dBm for iron sheet
and -23.13 dBm for aluminum sheet. We were also able to predict the shielding effectiveness of
the holes with different diameters and compared the result with those found by
analytical expression.
Acknowledgements
The authors would like to thank Kemenristek Dikti for the financial support of this
research for the period 2019.
5. TELKOMNIKA ISSN: 1693-6930
A low cost electromagnetic sensor for detecting holes in metallic sheet (Galang P. N. Hakim)
2485
References
[1] Shiraiwa T, Enoki M. Fatigue Crack Length Measurement of Sputtered Metal Film for RFID-based
Smart Stress Memory Patch. ISIJ International. 2011; 51(9): 1480–1486.
[2] Lammi CJ, Lados DA. Effects of Processing Residual Stresses on Fatigue Crack Growth Behavior of
Structural Materials: Experimental Approaches and Microstructural Mechanisms. Metallurgical and
Materials Transaction A. 2012; 43(1): 87–107.
[3] OSMA Assesments Team. NASA astronauts on Soyuz: experience and lessons for the future. NASA.
Report number: NASA/SP–2010–578. 2010.
[4] Martínez-Castro RE, Jang S, Nicholas J, Bansal R. Experimental assessment of an RFID-based
crack sensor for steel structures. Smart Materials and Structures. 2017; 26(8): 85035.
[5] Yi X, Cho C, Wang Y, Cook B, Tentzeris MM, Leon RT. Crack propagation measurement using a
battery-free slotted patch antenna sensor. 7
th
European Workshop on Structural Health Monitoring
(EWSHM). Nantes. 2014.
[6] Yi X, Cho C, Cooper J, Wang Y, Tentzeris MM, Leon RT. Passive wireless antenna sensor for strain
and crack sensing electromagnetic modeling, simulation, and testing. Smart Materials and Structures.
2013; 22(8): 085009.
[7] Marindra AMJ, Tian GY. Chipless RFID Sensor Tag for Metal Crack Detection and Characterization.
IEEE Transaction on Microwave Theory and Techniques. 2018; 66(5): 2452–2462.
[8] Sunny AI, Tian GY, Zhang J, Pal M. Low frequency (LF) RFID sensors and selective transient feature
extraction for corrosion characterisation. Sensors Actuators, A Physical. 2016; 241: 34–43.
[9] Albishi A, Ramahi OM. Detection of surface and subsurface cracks in metallic and non-metallic
materials using a complementary split-ring resonator. Sensors. 2014; 14(10): 19354–19370.
[10] Alahnomi RA, Zakaria Z, Yussof ZM, Sutikno T, Alhegazi A, Abu-Khadrah AI. Enhanced Symmetrical
split ring resonator (SSRR) for metallic surface crack detection. TELKOMNIKA Telecommunication
Computing Electronics and Control. 2019; 17(4): 2107–2115.
[11] Zhou J, Xu Y, Zhang T. A wireless monitoring system for cracks on the surface of reactor
containment buildings. Sensors. 2016; 16(6): 1–13.
[12] Zoughi R, Kharkovsky S. Microwave and millimetre wave sensors for crack detection. Fatigue and
Fracture of Engineering Materials and Structure. 2008; 31(8): 695–713.
[13] Liu Z, Chen K, Li Z, Jiang X. Crack Monitoring Method for an FRP-Strengthened Steel Structure
Based on an Antenna Sensor. Sensors. 2017; 17(10): 2394.
[14] Othman Z, Abdullah A, Kasmin F, Sakinah S, Ahmad SSS. Road Crack Detection using Adaptive
Multi Resolution Thresholding Techniques. TELKOMNIKA Telecommunication Computing Electronics
and Control. 2019; 17(4).
[15] Zhou B, Zhang J. Potential measurement in ECT system. Journal of Electrostatics. 2009; 67(1): 27–36.
[16] Lopato P, Herbko M. Microwave Structural Health Monitoring Sensor for Deformation Measurement
of Bended Steel Structures: Influence of Curvature Effect. Radioengineering. 2017; 26(4):
1060–1066.
[17] Lisowski M, Uhl T. Wireless Passive RFID-Based Sensor for Crack Detection-Second Stage of
Investigations. Key Engineering Materials. 2013; 588: 352–359.
[18] Wardoyo AS, Alaydrus M. Degradation of Shielding Performance of Metallic Sheet due to Aperture
Configuration and Dimension at 2.4 GHz. J Elektron dan Telekomun. 2018; 18(1): 9–14.
[19] Celozzi S, Araneo R, Lovat G. Electromagnetic Shielding. In: Chang K. Editor. Encyclopedia of RF
and Microwave Engineering. Wiley Interscience. 2018.
[20] Prayitno D, Irsyad M. Effect Of Ratio Of Surface Area On The Corrosion Rate. SINERGI. 2018; 22(1):
7-12. ISSN 24601217.
[21] Yashpal, Jawalkar CS, Kant S. A Review on use of Aluminium Alloys in Aircraft Components.
i-Manager’s Journal of Material Science. 2015; 3(3): 33–38.
[22] Permata D, Gurning MC, Martin Y, Sitorus HBH, Muda MA, Sinaga HH. Electromagnetic interference
shielding in unmanned aerial vehicle against lightning strike. TELKOMNIKA Telecommunication
Computing Electronics and Control. 2019; 17(2): 915–919.
[23] Haque MM, Limon SA, Moniruzzaman M, Bepari MM. Corrosion Comparison Of Galvanized Steel
And Aluminum In Aqueous Environments. International Journal of Automotive and Mechanical
Engineering (IJAME). 2014; 9: 1758-1767.
[24] Majid ZAA, Razak AA, Ruslan MH, Sopian K. Characteristics Of Solar Thermal Absorber Materials
For Cross Absorber Design In Solar Air Collector. International Journal of Automotive and Mechanical
Engineering (IJAME). 2015; 11: 2582-2590.
[25] Lantz G. Crack detection using a passive wireless strain sensor. MSC Thesis. Georgia Institute of
Technology. 2011.