Hasil untuk "Electric apparatus and materials. Electric circuits. Electric networks"

Yilin Zheng, Haijun Du, Honglong Cao et al.

Radio frequency identification (RFID) has been xtensively applied in e-commerce and logistics, significantly enhancing the level of management intelligence and efficiency, particularly in the real-time and automated tracking of commodities. This paper proposes a smart RFID gate system for access control utilizing a reconfigurable circularly polarized (CP) antenna with a fixed installation, which greatly simplifies the system architecture and improves the detection efficiency. The discrimination gate system comprises two primary components: a reconfigurable RFID CP antenna and a hardware control platform for autonomous data extraction and processing. The designed reconfigurable CP antenna functions in the frequency range of 805 to 1010 MHz with stable radiation gain and switchable polarization modes, which enables the discrimination of tag movement direction at the detection gate by examining the variation trend of ΔRSSI values from two orthogonal CP modes. To ensure the accuracy and effectiveness of detection results, an automated decision program has been developed, capable of determining door location and tag movement direction by fitting detected RSSI values and analyzing variation trend of ΔRSSI. Theoretical simulations and experimental validations have been performed to examine the proposed detection approach, confirming its feasibility and significant potential for applications in intelligent logistics management.

Ramakrishna Goli, Aravindhan Alagarsamy, Gian Carlo Cardarilli

The fast expansion of the Internet of Things (IoT) has increased the need for strong security measures to protect the enormous network of interconnected devices. This paper proposes a unique approach that combines optimization, intuitive design principles, and Least Weighted Elliptic Curve Cryptography (LWECC) to improve IoT device security while reducing power consumption. The proposed optimization strategy focuses on lowering computational overhead, which is critical for IoT devices with limited energy and processing power. The proposed method significantly reduces the amount of energy required for cryptographic operations by carefully selecting appropriate elliptic curves and optimizing cryptographic algorithms, ensuring that IoT devices may continue to function without compromising security. Furthermore, by selecting elliptic curves with minimal attack vulnerability, the use of LWECC provides an additional layer of protection. This technique ensures that, even in the face of emerging threats, IoT devices remain highly resilient, reducing the chance of security breaches while preserving functionality without using excessive power. Experimental results show a power consumption of only 0.156 W and 0.25 W for memory and router topologies, respectively, with an error margin of 0.01. The stated error margin pertains to the simulation-based evaluation of transmission-level data handling within the LWECC-enabled memory/router pipeline, rather than the risk of physical memory-cell failure or fabrication yield. The value shows the maximum amount of packet/data-stream loss detected during encrypted data transfer, rather than hardware memory reliability.

Noureddine Brakta

The integration of Battery Energy Storage Systems (BESS) is critical for mitigating voltage instability in low-voltage (LV) networks with high photovoltaic (PV) penetration. While metaheuristic algorithms offer powerful tools for optimizing BESS dispatch, their successful transition from theoretical models to practical application hinges on a nuanced understanding of their operational parameters. This paper presents a case study on the pragmatic design and tuning of a hybrid Particle Swarm Optimization-Grey Wolf Optimizer (PSO-GWO) for a six-dimensional, multi-BESS control problem. We chronicle the evolution of the simulation framework, highlighting critical implementation challenges and their solutions. Key findings demonstrate that optimizer population size, not just iteration count, is a decisive factor in control stability, particularly for computationally inexpensive configurations. We introduce a control oscillation metric as a key performance indicator and discuss the indispensable role of smart warm-starts and rate-limiting in generating physically viable and asset-safe control actions. The paper concludes that a successful BESS control strategy is defined not only by its ability to meet primary objectives like voltage regulation but also by the stability and practicality of the control signals it produces, presenting a crucial trade-off between computational budget and real-world viability.

Tobias Kaiser, Esther Gottschalk, Kai Biethahn et al.

This work presents Pasithea-1, a coarse-grained reconfigurable array (CGRA) that combines energy efficiency with CPU-like programmability. Its extensible instruction set uses sequential control flow in code fragments of up to 64 RISC-like instructions, which encode control and dataflow graphs in adjacency lists. Combined with dedicated, uniform processing elements, this enables fast compilation from C source code (1.4 s mean compile time). Demonstrator measurements reveal energy efficiency of up to 601 int32 MIPS/mW at 0.59V and performance of up to 148 MIPS at 0.90 V. Compared to a RISC reference system, mean energy efficiency is improved by 2.24× with 1.71× higher execution times across 12 of 14 benchmarks. Program-dependent factors underlying variations in energy efficiency are identified using dynamic program analysis. To reduce operand transfer energy, seven interconnect topologies are evaluated: a flat bus, five crossbar variants and a logarithmic network. Best results are obtained for a crossbar topology, reducing mean dynamic tile energy by 19 %. Furthermore, floating-point (FP) support is added to the instruction set and evaluated using three binary-compatible microarchitectures, presenting distinct area-performance-energy tradeoffs. The interconnect and FP microarchitecture explorations demonstrate that, unlike CGRAs utilizing low-level bitstreams, Pasithea’s instruction set hides microarchitectural details, which makes it possible to optimize hardware without severing binary compatibility.

Roland Nagy, István Szalai

Vibrations in road vehicles related to road surface damage have a number of harmful consequences for the health of the occupants and for the components of the vehicle. To mitigate these effects and support timely pavement repairs, continuous road condition monitoring is essential. Vibration-based measurement systems have gained prominence in recent years, but their accuracy can be significantly compromised by vehicle maneuvers, particularly on urban or curvy roads. Despite this, the influence of aggressive maneuvers has largely been overlooked in previous studies. In this paper, we address this gap by presenting a comprehensive investigation into the impact of abrupt maneuvers on vibration-based road quality measurement. We introduce a novel, computationally efficient soft-sensor algorithm that detects and isolates aggressive maneuvers using sensor data from existing road quality measurement systems, classifying them into four categories. This algorithm combines rule-based methods with machine learning, offering enhanced accuracy and lower computational costs compared to alternative approaches. In this way, the overall maneuver classification achieves an accuracy of 93%. By applying the introduced approach to identify and correct the influence of maneuvers, we achieved a 7% increase in accuracy of pavement quality classification in a suburban environment and a 10% increase in an urban environment. The proposed solution can be easily integrated into current vibration-based road quality measurement frameworks, enhancing their performance while maintaining scalability and low operational cost.

Lingxiang Hu, Xia Zhuge, Jingrui Wang et al.

Abstract Brain‐inspired neuromorphic computing is recognized as a promising technology for implementing human intelligence in hardware. Neuromorphic devices, including artificial synapses and neurons, are regarded as essential components for the construction of neuromorphic hardware systems. Recently, optoelectronic neuromorphic devices are increasingly highlighted due to their potential applications in next‐generation artificial visual systems, attributed to their integrated sensing, computing, and memory capabilities. In this review, recent advancements in optoelectronic synapses and neurons are examined, with an emphasis on their structural characteristics, operational principles, and the replication of neuromorphic functions. For optoelectronic synaptic devices, such as memristor‐ and transistor‐based ones, attention is given to the two primary weight update modes: the light‐electricity synergistic mode and the all‐optical mode. Optoelectronic neurons are discussed in terms of different device types, including threshold switch neurons and semiconductor laser neurons. Last, the challenges that impede the progress of optoelectronic neuromorphic devices are identified, and potential future directions are suggested.

Maximilian Scherzer, Mario Auer

In this article an integrated fully differential current amplifier is presented. It was designed for inductive sensor excitation, in this case for a fluxgate sensor, however the concept is applicable wherever a low noise and precise current is required. A brief review of some of the basic elements of the circuit is given, followed by the development of a model that takes into account output impedance limitations due to mismatch and stability criteria, an essential consideration in the design of a stable current amplifier for inductive loads. Based on the proposed model, the design and implementation of the current amplifier is outlined, identifying potential difficulties for on-chip integration. The final design was then fabricated using a standard 180nm CMOS technology. Measurement results show that the circuit draws only 2.8 mA from a 3.3V supply voltage and occupies a total area of 0.64 mm2. Special efforts were made to accurately evaluate the output impedance, whereby a value of 436k<inline-formula> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> was recorded. In addition, the current amplifier achieves an output-referred noise current of 2.5<inline-formula> <tex-math notation="LaTeX">$\text {nA}/\sqrt {\text {Hz}}$ </tex-math></inline-formula>, resulting in a measured signal-to-noise ratio of more than 105.2 dB for a bandwidth of 512 Hz at an output current of 9<inline-formula> <tex-math notation="LaTeX">$\text {mA}_{\text {p-p}}$ </tex-math></inline-formula>.

Zhuo Cheng, Jiangxin Li, Jianjun Zhang et al.

Absrtact: In order to solve the problem that the two-way flow of power and information between user nodes and service nodes in the smart grid poses a huge threat to the privacy and security of user data, and at the same time, the limitation of the power bureau's computing resources also brings users response delay, service quality degradation and other problems, the author proposes the application of edge computing technology in smart grid data security. Combining with edge computing technology, the author proposes a proxy blind signcryption scheme based on certificateless without bilinear mapping. By blinding the power and information, the signcrypter can not know the specific power consumption information of the user, so as to ensure the data privacy and security of the user. Implement forward security using proxy key update mechanism and perform batch verification of user signature ciphertext. The experimental results indicate that: The total running time required for executing proxy authorization and verification, proxy key generation, signature and decryption algorithms in this scheme is 5.617 ms, with a ciphertext length of 80 Bytes. Compared with other existing literature, the maximum reduction is 85.6 % and 86 %, respectively. Conclusion: This scheme is more suitable for protecting data security and privacy in the data transmission process of smart grids due to its lower running time and communication cost.

Ao Du, Daoqian Zhu, Zhiyang Peng et al.

Abstract Antiferromagnets (AFM) hold significant promise as ideal candidates for high‐density and ultrafast memory applications. Electrical manipulation of exchange bias (EB) has emerged as an effective solution to integrate AFMs into magnetic memories as active elements. In particular, spin‐orbit torque antiferromagnetic random‐access memory (SOT‐ARAM) is recently been demonstrated by using an AFM/FM hybrid free layer, which can simultaneously satisfy field‐free switching and good device scalability. However, the switching current density of the exchange bias in SOT‐ARAM devices is still high, and novel functionalities are exploited in this device scheme. In this study, the all‐electrical manipulation of the ARAM devices through the interplay of SOT and spin‐transfer torque (STT) is reported, both in three‐terminal and two‐terminal configurations. The SOT current density achieves a 40% reduction thanks to the incorporation of the STT current. Macrospin simulations are performed to illustrate the underlying mechanism. Further, a majority gate that can be decomposed into reconfigurable AND/OR functionalities in a single ARAM device is demonstrated, with an operation speed as fast as 2 ns. The results can advance the development of high‐performance memories and in‐memory computing.

Haoyu Chen, Bingxu Liu, Jiupeng Cao et al.

Abstract The Cu‐based halide semiconductor CuGaI4 was prepared by a high‐temperature melting method. Optoelectronic characterization and density functional theory calculations of CuGaI4 reveal a direct bandgap of 2.9 eV. The corresponding UV photodetector (PD) based on CuGaI4 demonstrates excellent UV response and rapid response time. In addition, a flexible PD based on CuGaI4 is prepared, which also displays excellent photoresponse characteristics and mechanical stability. This work provides a systematic study of this novel Cu‐based halide semiconductor and demonstrates the great potential of CuGaI4 for future UV optoelectronic devices.

Adrian Tang, Nacer Chahat, Yangyho Kim et al.

This article presents development of a UAV based frequency modulated continuous wave (FMCW) radar system for remotely sensing the water contained within snowpacks. To make the radar system compatible with the payload requirements of small UAV platforms, the radar electronics are implemented with CMOS technology, and the antenna is implemented as an extremely compact and lightweight metasurface (MTS) antenna. This article will discuss how the high absorption losses of snowpacks lead to dynamic range requirements much stricter than FMCW radars used for automotive and other sensing applications, and how these requirements are met through antenna isolation, leakage calibration and exploitation of the range correlation effect. The article discusses in detail the implementation of the radar system, the CMOS microwave and digital circuitry, and the MTS antenna. The developed radar was mounted on a drone and conducted surveys in both Idaho and Alaska during the 2022-2023 winter season. We present several of those field results.

Moh Herlambang Akasyah, Dinar Nugroho Pratomo

Industri perumahan telah mengalami pertumbuhan yang signifikan dalam beberapa tahun terakhir. Peningkatan dalam performa industri properti tidak berimbang dengan penerapan teknologi yang mengakibatkan pembelian rumah masih dapat menimbulkan kebingungan dan beban bagi banyak konsumen. Aktivitas transaksi properti perumahan yang memerlukan banyak sumber daya seringkali tidak efisien. Perkembangan teknologi perangkat keras saat ini memungkinkan komputasi untuk menampilkan objek 3D dapat dilakukan dengan mudah. Kemudahan dalam pembuatan model 3D pada komputer dapat dimanfaatkan untuk memberikan gambaran yang lebih detail tentang rumah yang akan ditransaksikan, tanpa harus menunggu pembangunan rumah sampel dari agen industri perumahan. Model 3D rumah yang telah dibuat dapat disampaikan kepada calon pembeli melalui berbagai cara, salah satunya menggunakan teknologi augmented reality (AR) berbasis Android. Aplikasi AR ini menggunakan metode Marker-Based dan dikembangkan menggunakan Unity dan Vuforia. Hasil dari penelitian ini menunjukkan bahwa penggunaan aplikasi augmented reality dapat membantu dalam pemasaran properti perumahan. Aplikasi ini memberikan pengalaman yang lebih interaktif dan memudahkan calon pembeli untuk memahami dengan lebih jelas tentang properti yang ditawarkan. AR memungkinkan calon pembeli melihat model 3D rumah secara nyata melalui perangkat mobile mereka. Aplikasi AR ini memiliki potensi untuk meningkatkan efektivitas dalam pemasaran properti perumahan.

Sungho Hwang, Dongchul Suh, Yoonmook Kang

This study analyzes the field performance of various solar cell designs. Most research and development efforts concerning solar cells aim to increase their efficiency or power under standard test conditions (STC). However, conducting an actual field performance analysis is crucial because of the various ambient conditions present in the field, including temperature, irradiance, PV system installation, and albedo. These conditions can result in different performance results compared to STC. This study compares and analyzes case studies to assess field performance. One particular case study compares the field performance of monofacial modules with a monofacial passivated emitter and rear cell (PERC) and bifacial PERC at a carport system in the ambient conditions of the Korean Peninsula during summer and winter. The module material properties (white EVA and white backsheet) can impact module performance owing to the transmittance spectra at longer wavelengths. Certain transmittance values also contribute to the bifaciality number. Although the monofacial cell demonstrates better STC results, the field performance of the bifacial cell is superior in terms of energy yield and cost-effectiveness. Therefore, this study highlights the importance of considering the field performance (energy yield), in addition to STC, when designing solar cells and modules.

B. Ranganatha Rao, B. Sujatha

Cloud computing provides the users a centralized place for data storage and other commercial applications. To guarantee everything is secure, cloud security has to handle all the devices, apps, and data connected to the cloud. Because of the cloud's robust security, the data and applications may be accessed by the relevant people. The usage of public cloud security ensures that customers always have a trustworthy method of accessing apps and data, which in turn enables service providers to resolve any potential security problems as soon as they arise. This paper presents a public cloud security technique using Hybrid Elliptic Curve Cryptography (HECC). The proposed approach makes keys using a lightweight Edwards curve. The user's Identity Based Encryption is used to change the generated private keys. The proposed key reduction method is used to make the keys even shorter, which speeds up the Advanced Encryption standard (AES) encryption process. The public keys are exchanged using Diffie Hellman key exchange. Throughput and key generation, encryption, and decryption times are used to evaluate how well the suggested model performs. The suggested model fared better than the current models in every way. The suggested method's key creation process takes 0.000025 s, while the resulting encryption process takes 0.00349 s. The achieved throughput is 693.10 kB/s.

Dankan Gowda V, Avinash Sharma, Rajesh L et al.

In the era of modern medical imaging communal, huge volume of medical image data are being acquired and need to be transmitted and archived which necessitate the development of efficient image compression techniques on both 2D and 3D images. The compression of medical images is an essential process to support remote healthcare services. The medical diagnostics through these services require more accurate information from an image. As the property of inverse proportionality between the compression rate and quality of the image takes place in any kind of compression method, there is a need to sacrifice any one of those credentials (Quality or Compression Rate). With this context, Region of Interest (ROI) codecs are emerging and reduces this proportionality that yields more compression rate without compromising the quality. In this paper, presents an ROI based near lossless image compression method that incorporates the Set Partitioning in Hierarchical Trees (SPIHT) and Vector Quantization coding for medical images.

Jakub Svatos, Jan Holub, Jan Fischer et al.

COVID -19 pandemic and its restrictions bring new challenges to all aspects and phases of higher education. At universities, new remote formats have been developed and deployed for lectures and laboratory exercises. This article addresses challenges and introduces the new experience with lectures and laboratory classes during the pandemic time at the Department of Measurement of the Czech Technical University in Prague, Faculty of Electrical Engineering. Based on the student survey of more than 250 students describes the possibilities of how to adapt the lectures during the lockdown. The article also introduces the Home Lab, a tool developed in the department that helps in distance teaching practical electronic classes. Home Lab includes two parts with functional groups, a Laboratory Experimental Device and a System of Measurement Instruments. The article also shows the opportunity for suitable remote exercises and variants of circuits that can be easily assembled and measured using Software Defined Instrument based on various microcontrollers. A detailed description of all Software Defined Instruments is also present. During the Pandemic, the home lab model was successfully practically verified during distance learning in three subjects, with more than 150 students per semester. It has also been shown that the Home Lab can be successfully deployed for a semester project. The article also presents experience with the teaching software-oriented courses. At the end of the article, practical knowledge and an experience from distance teaching during a three-semester lockdown are shared.

Y Mohana Roopa, T. SatheshKumar, Thayyaba Khatoon Mohammed et al.

Conventional power transmission and distribution schemes have been completely transformed by the development of the Smart Grid (SG). Nearly every field has been impacted by technology and advancements, including smart grids. Electricity also isn't inexpensive to produce, so Smart Meters (SM) play a crucial role in controlling, managing, and performing efficiency to use the electricity successfully on the customer side, which would be referred to as demand side management (DSM). A Home Energy Management System (HEMS) has been proposed in the research study as a way of optimizing home appliances and saving as much money as possible. The Eagle Hard Optimization (EHO) method and our hybridization of the EHO technique have been implemented. EHO appears to be a Genetic Algorithm (GA) known as a Genetic EHO (GEHO). Compared to normal EHO and unplanned systems, simulation results showed that GEHO better planned the devices to lower the maximum price. Peak to Average Ration packs (PAR) has additionally been noted. Due to the planning of the largest amount of devices on both sides, GEHO& unforeseen has PAR equal, while EHO has a low PAR. Various Operation Time Intervals (OTI) were used to help in efficiency measures. With each of the three plans, capacity &amp; costs money have indeed been thoroughly analyzed.

Chanachon Paijitprapaporn, Thayathip Thongtan, Chalermchon Satirapod

Global Navigation Satellite System (GNSS) is space-based systems for positioning, navigation and timing. Non-GNSS sources are aiding to maintain accuracy of system states including positioning, velocity, acceleration, attitude and angular rate essential in applications involving reliable and accurate real-time navigation solutions, safety-of-life systems and control of trajectory. Although GNSS capabilities are rapidly increased, challenges still exist when GNSS signals are not available and spoofing is mitigated; therefore, integrated information from different sources including GNSS, Inertial Navigation System (INS), Distance Measuring Instrument (DMI) and Terrestrial Laser Scanner (TLS) are required to maintain system state or improve navigation system performances. This paper presents integration information from GNSS and various sources available in a terrestrial light detection and ranging (LIDAR) mobile mapping system where a tight coupled system; in observation domain, is formulated and various GNSS measurements are applied to access its positioning accuracy in urban scenes throughout the advantages, disadvantages and trade-offs.

Tung-Yuan Yung, Thangavel Sangeetha, Wei-Mon Yan et al.

Nanocomposite catalysts composed of non-precious nanoparticles anchored by modified graphene for oxygen reduction reactions (ORRs) are the emphasis of research nowadays for wide application in electrocatalyst systems. Herein, an endeavor is made to report on a one-pot synthesis method to produce a catalyst for Fe3O4 and Ni–NiO nanoparticles on Polydiallyldimethylammonium chloride-modified graphenes (PDDA-G). The nanocomposite is characterized by spectral measurements, using scanning electron spectroscopy (SEM), transmitting electron spectroscopy (TEM), x-ray diffractometer (XRD) and Raman spectroscopy to reveal its microstructure. Through a layer-by-layer PDDA-G investigation, a significant anchoring of nanoparticles and maintenance of the graphene with good electron transporting properties and spatial distance in nanoscale by PDDA is achieved. Additionally, the electrochemical properties of Fe3O4@PDDA-G and Ni–NiO@PDDA-G are demonstrated by linear scan voltammetry (LSV) with rotation disk electrode (RDE). Fe3O4@PDDA-G displays prominent ORR activity in 2-electron and 4-electron pathways, and better ORR mass activities than Ni–NiO@PDDA-G and commercial Pt/C. The results of this study provide a new strategy to develop material design approaches for high-performance electrocatalysts to be employed in fuel cells.

BENAROUS Leila, DJOUDI Mohamed, BOURIDANE Ahmed

Steganography is one of the oldest methods of secure communication. It was an art at the beginning, now became a science. It aims to conceal secret messages or data inside an innocent cover. Steganalysis is the science that can detect and extract hidden data. Many steganography and steganalysis tools exist, a lot of them are free which makes it easy for anyone to use these tools. In this paper, a comparative study will be done between two widely used steganography tools (StegHide and OurSecret) and between three steganalysis tools StegSpy, StegSecret and Hidden data detector.