Power Consumption Of Devices Research Articles

Development of a rotary piezoelectric energy harvester using magnetic excitation inspired by the fan blade

This work proposes a new rotary piezoelectric energy harvester using magnetic excitation inspired by the fan blade. The configuration and operating principle of the harvester are introduced. Then, the equivalent nonlinear model of the piezoelectric beam is established based on the Euler–Bernoulli theory and the Rayleigh–Ritz method. Finite element simulation is used to obtain the vibration performance of the piezoelectric beam, and the first order natural frequency is obtained as 22.059 Hz. A prototype of the proposed harvester is developed, and a series of experiments are carried out. The effect of magnet deflection angle, magnet mass, and the number of magnets on the output performance of the harvester is studied in detail by experiments. The experimental results proved that the harvester obtained a relatively better output performance when the deflection angle of the drive magnet is 30°. In addition, the harvester generated the maximum output voltage when the rotary speed is 165 rpm, which is consistent with the simulation result. The harvester achieved an average power of 43.5 mW when the resistance was 130 kΩ under the rotary speed of 165 rpm. The output power can satisfy the power consumption of low-power electronic devices, such as LEDs, calculators, and electronic meters.

Advanced exergy analysis of a novel mass integration cogeneration system driven by geothermal energy

To mitigate fossil energy consumption and increase renewable energy use, a novel mass integration cogeneration system (MICS) driven by geothermal energy is proposed in this work. Parametric evaluations are conducted in order to ascertain crucial system parameters. The system is analyzed thermodynamically utilizing exergy analysis and advanced exergy analysis. The findings indicate a direct relationship between the refrigeration coefficient of performance and the power generation efficiency, as well as the mass flow rate of the working fluid, the turbine input pressure, the valve outlet pressure, and the mass fraction of the working fluid at the generator outlet. Exergy analysis reveals that the exergy efficiency of the MICS is greater than 0.85. The condenser exhibits the highest exergy destruction, amounting to 54.52 kW. Given that around 40 % of exergy destruction in power consumption devices (such as turbines, compressors, and pumps) is preventable, there is significant potential for improvement. Furthermore, the MICS employs 50 % less working fluid compared to a heat integration cogeneration system. The implementation of advanced exergy analysis in this study will facilitate the progress of geothermal energy utilization systems, while the investigation of optimization possibilities will assist in their practical deployment in the industry.

Mutual Synchronization of Spintronic Nano-Oscillator Ensembles

Introduction. The use of spintronic components significantly enhances the performance, reduces the size, and lowers the power consumption of modern electronic devices. The spintronic oscillator (SO) is an integral part of spintronic devices. Connecting several SOs (> 100) into ensembles with subsequent synchronization mitigates such SO drawbacks as low output power and high phase noise. These drawbacks appear as a result of an increase in the output power of an SO ensemble compared to a single oscillator under a simultaneous decrease in the spectral linewidth of the ensemble.Aim. To investigate the impact of connection topologies, synchronization mechanisms, and oscillator failures on the synchronization of oscillator ensembles.Materials and methods. The Kuramoto phase model was used to simplify the numerical modeling of synchronization of SOs connected into an ensemble.Results. A Kuramoto equation for phases of SOs connected in an ensemble was derived, and the influence of connection topologies and oscillator failures on the synchronization parameters of an ensemble of N connected oscillators was demonstrated.Conclusion. In order to ensure the shortest transition time of an SO ensemble to the synchronous mode, topologies with a higher number of connections between oscillators (e.g., "all-to-all") are preferable. The results obtained confirm the advantages of local connection of an SO ensemble by a common current, thus forming an "all-to-all" topology. This makes the transition time of the SO ensemble to the synchronous mode less dependent on both oscillator failures and the number of synchronized SOs.

Integration of CeO2-Based Memristor with Vertically Aligned Nanocomposite Thin Film: Enabling Selective Conductive Filament Formation for High-Performance Electronic Synapses.

The CeO2-based memristor has attracted significant attention due to its intrinsic resistive switching (RS) properties, large on/off ratio, and great plasticity, making it a promising candidate for artificial synapses. However, significant challenges such as high power consumption and poor device reliability hinder its broad application in neuromorphic microchips. To tackle these issues, in this work, we design a novel bilayer (BL) memristor by integrating a CeO2-based memristor with a Co-CeO2 vertically aligned nanocomposite (VAN) layer and compare it with the single layer (SL) memristor. Preliminary electrical testing reveals that the BL memristor offers a reduced set/reset voltage (∼67% lower), a higher on/off ratio (∼5 × 102), enhanced device reliability, and improved device-to-device variation compared to the SL memristor. Insight from COMSOL simulation, coupled with microstructural analysis, provides a comprehensive elucidation on how the VAN layer facilitates the selective conductive filament (CF) formation. Subsequently, the plasticity of the BL memristor is evaluated through long-term potentiation/depression (LTP/LTD), paired-pulse facilitation (PPF), and spike-time-dependent plasticity (STDP). The spiking neural network (SNN) built upon the BL memristor achieves remarkable accuracy (∼94%) after only 12 iterations, underscoring its potential for high-performance neural networks.

Mid-infrared arrayed waveguide gratings using a quantum cascade laser gain medium as core material

Mid-infrared photonics is a widely researched field with several applications, such as chemical sensing and spectroscopy. The development of photonic integrated circuits for the mid-infrared can enable the reduction in device size, weight, and power (SWaP) consumption. This paper demonstrates arrayed waveguide gratings working in the mid-infrared regime (5–5.4 µm). Our devices are fabricated on an InP-based quantum cascade laser platform with the gain medium as the waveguide core. To minimize the propagation losses caused by free carrier absorption and intersubband absorption in the unbiased QCL structure, we exposed the photonic chips to proton implantation. The performance of three sets of AWGs with different etch depths was characterized. The lowest waveguide losses were measured to be 2 dB/cm. The best performing 7×1 AWG and 13×1 AWG designs featured insertion losses of −2dB and −2.5dB, respectively. This study showcases the feasibility of applying such a platform for easy integration with active components like lasers and photodetectors, paving the path for on-chip mid-infrared applications.

New tile-based circuits converting BCD code to gray, excess-3, and aiken codes in quantum-dot cellular automata (QCA) nanotechnology

The development of new methods and technologies for improving the stability and reducing the power consumption of electronic devices is a crucial area of research. Quantum-dot Cellular Automata (QCA) has emerged as a promising alternative to the traditional Complementary Metal-Oxide-Semiconductor (CMOS) technology, offering superior optimization in terms of physical size and energy efficiency. This paper introduces three novel digital code converters, designed using the tile-based approach to simplify circuit implementation and enhance integration through optimized majority and inverter gate structures. The proposed converters include: (1) a BCD to gray code converter with 127 cells, 0.18 μm2 occupied area, 3 clock phases, and zero NOT gate achieving a 7.3 % and 100 % reduction in the number of cells and NOT gates, respectively, compared to the most similar design; (2) a BCD to excess-3 code converter with 190 cells, 0.25 μm2 occupied area, 7 clock phases, and 3 NOT gates, showing a 0.5 %, 13.8 %, 41.7 %, and 25 % reduction in cells, area, used clock phases, and NOT gates, respectively, compared to the closest alternative; and (3) a BCD to aiken (2421) code converter with 287 cells, 0.22 μm2 occupied area, zero NOT gate, and 5 clock phases. The energy dissipation for these converters is measured at 55.3 meV, 53.7 meV, and 102 meV, respectively. Simulations are performed using QCADesigner-E version 2.2, validating the functionality and performance of the designs. These results demonstrate the potential of the proposed converters to offer efficient, compact, and low-power solutions for digital systems.

Research on Techniques for Enhancing the Speed of Low-Power Operational Amplifier

In the context of low utilization, this paper explores various techniques for enhancing the speed of operational amplifier (OA). The main text delves into three methods to gain equilibrium: fully differential operational amplifier (FDA), twostage operational transconductance amplifier (OTA), and a novel high-speed calculation system architecture employing a “rhombus crystal tube.” The FDA improves speed by minimizing noise and enhancing bandwidth and output voltage swing, without increasing power consumption. The design of the two-stage OTA combines the characteristics of a differential amplifier and a telescopic amplifier, optimizing gain and slew rate through Miller compensation and noise gain manipulation, thereby achieving high-speed performance. A novel high-speed operational amplifier structure employs diamond transistors to supply substantial current for capacitor charging, enhancing the slew rate and overall speed. Throughout the text, these methods are presented as a means to jointly promote high speed, low power consumption, and the handling of a significant number of transistors. To further increase the speed, the size of the microcrystalline tube is crucial. The research direction is outlined, and while the design equipment is in the foreground, there remains room for progress, especially in applications for large-scale electrical models. Future research aims to enhance the power efficiency of circuits, making them more practical and efficient. This study provides valuable insights into balancing power consumption and speed in advanced electronic devices.

Pengembangan Mesh Network Sebagai Ekspansi Protokol LoRaWAN di Politeknik Negeri Malang

In realizing a smart campus, Politeknik Negeri Malang (Polinema) has implemented digital technology in its learning and administrative processes with the goal of improving efficiency, speed, and operational ease. One of the key areas being developed is the Internet of Things (IoT), which is expected to function autonomously to support various campus activities. However, the main challenges in IoT implementation are the limitations in communication range and device power consumption, which cause issues in sensor and actuator data transmission, especially when data cannot be optimally received between nodes. To address these challenges, Polinema is ex-ploring the application of LoRaWAN technology. Although LoRaWAN is effective, it experiences a decline in data transmission quality when the sender and receiver are located in multi-story buildings, which can lead to delays, packet loss, or other disruptions. As a solution, the use of a Mesh Network is proposed to enhance the range and stability of data transmission. This study collected data using RSSI, SNR, and delay parameters in the civil engineering building at Polinema, with sensor data visualized through Grafana. The results show that the system can be well-integrated without conflicts between WiFi and LoRa. The average transmission time was approximately 29 seconds, with no packet loss detected. Additionally, changing the transmission method to confirmed uplink was necessary to maintain data integrity, while adjusting transmis-sion intervals was crucial to avoid scheduling issues. These findings indicate that implementing a Mesh Network as an extension of the LoRaWAN protocol can significantly improve the perfor-mance of IoT systems in Polinema’s indoor environment.

A Developer-Oriented Framework for Assessing Power Consumption in Mobile Applications: Android Energy Smells Case Study

Currently, people spend a lot of time using their mobile devices. With such ubiquity of mobile devices in our daily life, battery capacity and quality are of utmost importance. Running software applications (called apps) are one of the major factors influencing the power consumption in mobile devices. In order to meet user needs, mobile apps are becoming inherently complex and resource greedy. Therefore, fulfilling these requirements at the pace imposed by the market may degrade software construction quality and insert so-called energy code smells: bad patterns in the source code of an app that indicate a deeper problem and adversely affect power consumption. This work proposes a developer-oriented framework for identifying and fixing patterns via analyzing different application code flavors in a user-driven test scenario. A special app was designed in order to validate the Android implementation of the proposed methodology. The study results have shown significant improvement regarding energy efficiency after correcting one or more energy code smells, with a 4 to 30 percent decrease in battery drain. Additionally, the power consumption signature term is defined in the context of mobile applications. This paper presents a developer-oriented framework for assessing power consumption in mobile applications. Our key contributions include identifying significant energy code smells, demonstrating their impact on power consumption, and providing a toolset for developers to improve energy efficiency.

Unlocking amplified magneto-photocurrent using multi-field manipulation in nonfullerene organic bulk heterojunction systems.

An effective manipulation of polaron pairs (PPs) for realizing amplified magneto-photocurrent (AMPC) is of critical importance toward the development of low power consumption and high-performance organic spin-optoelectronic devices, for instance magneto-photo-volatile memories. By far, it is challenging and there is a lack of method to reach AMPC. The typical magneto-photocurrent due to the light-matter interanion is primarily for unveiling the spin-dependent electron-hole dissociation in organic solar cells. Herein, we achieved an AMPC of ∼140% in nonfullerene organic bulk heterojunction systems at room temperature. We found that the amplification can be effectively triggered by a multi-field to a large number of photogenerated PPs at intermediate charge transfer states. We further postulate that, at steady state, they may experience a cyclic photophysical process due to the triplet-exciton polaron interaction. This study paves the way for the realization of AMPC in the organic spin-optoelectronic system.

RDSC: Range-Based Device Spatial Clustering for IoT Networks.

The growth of the Internet of Things (IoT) has become a crucial area of modern research. While the increasing number of IoT devices has driven significant advancements, it has also introduced several challenges, such as data storage, data privacy, communication protocols, complex network topologies, and IoT device management. In essence, the management of IoT devices is becoming more and more challenging, especially with the limited capacity and power of the IoT devices. The devices, having limited capacities, cannot store the information of the entire environment at once. In addition, device power consumption can affect network performance and stability. The devices' sensing areas with device grouping and management can simplify further networking tasks and improve response quality with data aggregation and correction techniques. In fact, most research papers are looking forward to expanding network lifetimes by relying on devices with high power capabilities. This paper proposes a device spatial clustering technique that covers crucial challenges in IoT. Our approach groups the dispersed devices to create clusters of connected devices while considering their coverage, their storage capacities, and their power. A new clustering protocol alongside a new clustering algorithm is introduced, resolving the aforementioned challenges. Moreover, a technique for non-sensed area extraction is presented. The efficiency of the proposed approach has been evaluated with extensive experiments that gave notable results. Our technique was also compared with other clustering algorithms, showing the different results of these algorithms.

A Review of Integrated Photonic Devices Using Sb2Se3

AbstractThe silicon photonic technology is a highly promising option for photonic integrated circuits and has attracted intensive interests, particularly since it can utilize complementary metal‐oxide‐semiconductor processing techniques and facilities, thereby realizing high‐density photonic integrations with low‐cost. Unfortunately, the thermo‐optic and the carrier dispersion effects, which are the typical means of tuning silicon photonics devices, bring the drawbacks of high power consumption and large device size due to the relatively weak effect with a small refractive index change and being volatile. For overcoming these drawbacks, phase‐change materials are introduced into silicon photonic devices, where VO2 and Ge2Sb2Te5 are the most commonly used ones. However, the key disadvantage of large loss resulting from them limits further improving the performances of integrated photonic devices. Therefore, Sb2Se3 has seen increasing interests recently in the design of silicon photonic integrated devices, benefiting from the advantages of having extremely low loss over the C‐band and being non‐volatile. In this paper, the trending recent studies about integrated optical devices are systematically reviewed using Sb2Se3, which are classified according to the device function.

Ultrahigh Stability and Operation Performance in Bi-doped GeTe/Sb2Te3 Superlattices Achieved by Tailoring Bonding and Structural Properties.

Changes in bond types and the reversible switching process between metavalent and covalent bonds are related to the operating mechanism of the phase-change (PC) behavior. Thus, controlling the bonding characteristics is the key to improving the PC memory performance. In this study, we have controlled the bonding characteristics of GeTe/Sb2Te3 superlattices (SLs) via bismuth (Bi) doping. The incorporation of Bi into the GeTe sublayers tailors the metavalent bond. We observed significant improvement in device reliability, set speed, and power consumption induced upon increasing Bi incorporation. The introduction of Bi was found to suppress the change in density between the SET and RESET states, resulting in a significant increase in device reliability. The reduction in Peierls distortion, leading to a more octahedral-like atomic arrangement, intensifies electron-phonon coupling with increased bond polarizability, which are responsible for the fast set speed and low power consumption. This study demonstrates how the structural and thermodynamic changes in phase change materials alter phase change characteristics due to systematic changes of bonding and provides an important methodology for the development of PC devices.

Optimization Analysis of MOSFET Structure and Application

Metal Oxide Semiconductor Field Effect Transistor (MOSFET) is a crucial power semiconductor device used in electronic equipment, playing a key role in various electronic systems and power electronics. As electronic technology advances, the demand for MOSFETs is increasing, requiring higher switching speeds, lower power consumption, enhanced reliability, and improved integration. Therefore, optimizing MOSFETs and exploring their applications is of significant research importance. This article presents an analysis conducted by both domestic and international scholars, focusing on topics such as the use of asymmetric inner surface oxide, layout optimization of bipolar MOSFETs, design enhancements of fully-encircled gate (GAA) MOSFETs, and studies on double-layer epitaxial structures. Additionally, it discusses the potential applications of MOSFETs in automotive electronic systems. Furthermore, the article delves into the future prospects of MOSFETs, highlighting the exploration of new materials, technological advancements, and heterogeneous integration to achieve higher performance, smaller size, and lower power consumption in devices. Furthermore, these findings from the research assist in guiding ongoing advancements in MOSFET technology and provide an outline of potential future developments.

A Taxonomy of Low-Power Techniques in Wearable Medical Devices for Healthcare Applications

Chronic diseases are the most prevalent and non-communicable health crisis globally. Most chronic disease patients require continuous physiological monitoring, using wearable technology for timely treatment, precise illness detection, and preventive healthcare. Nonetheless, efficient power management is required for such resource-constrained wearable devices. This work aims to analyze low-power techniques (LPTs) in wearable medical devices using a data-driven approach and identify novel approaches promising higher power savings. Through an intensive literature analysis, we identify the most relevant LPTs for minimizing power consumption in wearable devices for physiological monitoring while recognizing the barriers to adopting these techniques. As a result, a novel taxonomy based on the common characteristics of the LPTs is proposed, along with strategies for the combination of LPTs. Through our analysis, we propose possible enhancements in using LPTs and suggest mechanisms for the medical device industry to facilitate their adoption. Overall, our proposed strategies guide the use of LPTs on wearable medical devices toward continuous physiological monitoring.

Electrically Reconfigurable Phase-Change Transmissive Metasurface.

Programmable and reconfigurable optics hold significant potential for transforming a broad spectrum of applications, spanning space explorations to biomedical imaging, gas sensing, and optical cloaking. The ability to adjust the optical properties of components like filters, lenses, and beam steering devices could result in dramatic reductions in size, weight, and power consumption in future optoelectronic devices. Among the potential candidates for reconfigurable optics, chalcogenide-based phase change materials (PCMs) offer great promise due to their non-volatile and analogue switching characteristics. Although PCM have found widespread use in electronic data storage, these memory devices are deeply sub-micron-sized. To incorporate phase change materials into free-space optical components, it is essential to scale them up to beyond several hundreds of microns while maintaining reliable switching characteristics. This study demonstrated a non-mechanical, non-volatile transmissive filter based on low-loss PCMs with a 200 × 200 µm2 switching area. The device/metafilter can be consistently switched between low- and high-transmission states using electrical pulses with a switching contrast ratio of 5.5 dB. The device wasreversibly switched for 1250 cycles before accelerated degradation took place. The work represents an important step toward realizing free-space reconfigurable optics based onPCMs.

Shear Thickening Fluid and Sponge-Hybrid Triboelectric Nanogenerator for a Motion Sensor Array-Based Lying State Detection System.

Issues of size and power consumption in IoT devices can be addressed through triboelectricity-driven energy harvesting technology, which generates electrical signals without external power sources or batteries. This technology significantly reduces the complexity of devices, enhances installation flexibility, and minimizes power consumption. By utilizing shear thickening fluid (STF), which exhibits variable viscosity upon external impact, the sensitivity of triboelectric nanogenerator (TENG)-based sensors can be adjusted. For this study, the highest electrical outputs of STF and sponge-hybrid TENG (SSH-TENG) devices under various input forces and frequencies were generated with an open-circuit voltage (VOC) of 98 V and a short-circuit current (ISC) of 4.5 µA. The maximum power density was confirmed to be 0.853 mW/m2 at a load resistance of 30 MΩ. Additionally, a lying state detection system for use in medical settings was implemented using SSH-TENG as a hybrid triboelectric motion sensor (HTMS). Each unit of a 3 × 2 HTMS array, connected to a half-wave rectifier and 1 MΩ parallel resistor, was interfaced with an MCU. Real-time detection of the patient's condition through the HTMS array could enable the early identification of hazardous situations and alerts. The proposed HTMS continuously monitors the patient's movements, promptly identifying areas prone to pressure ulcers, thus effectively contributing to pressure ulcer prevention.

Model-Based Thermal Stress and Lifetime Estimation of DFIG Wind Power Converter

Turbine systems equipped with doubly fed induction generation (DFIG) are becoming increasingly vital in wind power generation, with the reliability of the devices serving as a pillar in the industrial sector. Thermal stress and lifetime assessment are fundamental indicators in this regard. This paper primarily addresses the thermal stress and lifespan of power semiconductor devices utilized in a DFIG grid-side converter (GSC) and rotor-side converter (RSC). PLECS (Piecewise Linear Electrical Circuit Simulation) is employed to validate the electrical and thermal stress of the power devices. Additionally, Ansys Icepak, a finite element analysis (FEA) software, is utilized to confirm temperature fluctuations under various operations. The power consumption and junction temperature of the power devices in the GSC and RSC of a 2 MW DFIG are compared. It is evident that the most stressed power semiconductor is the IGBT for the GSC with a temperature swing of 3.4 °C, while the diode in the RSC is the most stressed with a temperature swing of 10.1 °C. This paper also presents a lifetime model to estimate the lifespan of the power device based on the annual wind profile. By considering the annual mission profile, we observe that the lifetime of the back-to-back power converter is limited by the diode of the RSC, whose B10 lifetime is calculated at 15 years.

Superimposed Semantic Communication for IoT-Based Real-Time ECG Monitoring.

Real-time electrocardiogram (ECG) monitoring and diagnosis through Internet of Things (IoT) are crucial for addressing the severity and timely treatment of cardiovascular diseases, enabling timely intervention and preventing life-threatening complications. However, current ECG monitoring research predominantly focuses on individual aspects such as signal compression, diagnostic analysis, or secure transmission, lacking joint optimization of various modules in IoT scenarios. To address this gap, this work proposes a novel framework based on superimposed semantic communication for real-time ECG monitoring in IoT. The framework comprises three hierarchical levels: the edge level for data collection and processing, the relay level for signal compression and coding, and the cloud level for data analysis and reconstruction. The proposed framework offers several unique advantages. By employing semantic encoding guided by ECG classification tasks, it selectively extracts crucial features within and between signals, improving compression ratio and adaptability to channel noise. The superimposed semantic encoding achieves content encryption without requiring any additional operations. Moreover, the framework utilizes lightweight anomaly detection neural networks, reducing edge device power consumption and conserving communication resources. Simulation and real experimental results demonstrate that the proposed method achieves real-time encoding and transmission of ECG signals with a compression ratio of 0.019 on the MIT-BIH dataset. Furthermore, it attains a heartbeat classification accuracy of 0.988 and a reconstruction error of 0.061.

Research on portable airway impedance monitoring device based on expiratory oscillation

Monitoring airway impedance has significant clinical value in accurately assessing and diagnosing pulmonary function diseases at an early stage. To address the issue of large oscillator size and high power consumption in current pulmonary function devices, this study adopts a new strategy of expiration-driven oscillation. A lightweight and low-power airway impedance monitoring system with integrated sensing, control circuitry, and dynamic feedback system, providing visual feedback on the system's status, was developed. The respiratory impedance measurement experiments and statistical comparisons indicated that the system could achieve stable measurement of airway impedance at 5 Hz. The frequency spectrum curves of respiratory impedance ( R and X) showed consistent trends with those obtained from the clinical pulmonary function instrument, specifically the impulse oscillometry system (IOS). The differences between them were all less than 1.1 cm H 2O·s/L. Additionally, there was a significant statistical difference in the respiratory impedance R5 between the exercise and rest groups, which suggests that the system can measure the variability of airway resistance parameters during exercise. Therefore, the impedance monitoring system developed in this study supports subjects in performing handheld, continuous measurements of dynamic changes in airway impedance over an extended period of time. This research provides a foundation for further developing low-power, portable, and even wearable devices for dynamic monitoring of pulmonary function.