Hasil untuk "Electronics"

Christoph Balada, Max Bondorf, Sheraz Ahmed et al.

Electricity grids have become an essential part of daily life, even if they are often not noticed in everyday life. We usually only become particularly aware of this dependence by the time the electricity grid is no longer available. However, significant changes, such as the transition to renewable energy (photovoltaic, wind turbines, etc.) and an increasing number of energy consumers with complex load profiles (electric vehicles, home battery systems, etc.), pose new challenges for the electricity grid. At the same time, these challenges are usually too complex to be solved with traditional approaches. In this gap, where traditional approaches are reaching their limits, Machine Learning has become a popular tool to bridge this shortcoming through data-driven approaches. To enable novel ML implementations is we propose FiN-2 dataset, the first large-scale real-world broadband powerline communications (PLC) dataset. FiN-2 was collected during real practical use in a part of the German low-voltage grid that supplies energy to over 4.4 million people and shows well over two billion data points collected by more than 5100 sensors. In addition, we present different use cases in asset management, grid state visualization, forecasting, predictive maintenance, and novelty detection to highlight the benefits of these types of data. For these applications, we particularly highlight the use of novel machine learning architectures to extract rich information from real-world data that cannot be captured using traditional approaches. By publishing the first large-scale real-world dataset, we also aim to shed light on the previously largely unrecognized potential of PLC data and emphasize machine-learning-based research in low-voltage distribution networks by presenting a variety of different use cases.

Jingbo Li, Yile Fang, Zhuhao Wu et al.

Islet transplantation is a promising strategy for diabetes mellitus treatment as it can recapitulate endogenous insulin secretion and provide long-term glycemic control. Islet models constructed in biomaterial scaffolds that reproduce biological characteristics of native islets is a feasible option to circumvent the dilemma of donor shortage and the requirement of chronic immunosuppression. Herein, we developed bioinspired artificial microcapsule-based islet models with microvessels for glycemic control using microfluidic electrospray strategy. Microfluidic electrospray can generate uniform hydrogel microcapsules with core-shell structure for encapsulating islet cells. The cell-laden microcapsules enabled the efficient transportation of nutrient, oxygen, and insulin; as well as the incorporation with microvessels for prompting glucose responsiveness and molecular exchange. We demonstrated by in vivo experiments that the blood glucose, food intake, and body weight of diabetic mouse models were alleviated, and the glucose tolerance was promoted after the engraftment of islet microcapsules. We further demonstrated the improved functionality of transplanted islet model in insulin secretion, immune escape, and microcirculation using standard histological and molecular analysis. These results indicated that the microcapsules with microvessels are promising artificial islet models and are valuable for treating diabetes.

Gowri Prasood Usha, John Sahaya Rani Alex

Aphasia, a language disorder caused by brain injury, presents significant speech recognition and classification challenges due to irregular speech patterns. While the standard Grad-CAM (Gradient-weighted Class Activation Mapping) technique is widely used for model interpretation, its application to impaired speech remains largely unexplored. To address this gap, we introduce a set of extension studies of enhanced Grad-CAM techniques, namely Enhanced Directional Grad-CAM (ED-GCAM), Multi-Scale Channel-wise Grad-CAM (MSCW-GCAM), Stochastic Gradient-Dropout Integrated Grad-CAM (SGD-GCAM), and Enhanced Hierarchical Filtered Grad-CAM (EH-FCAM) to improve interpretability and performance in aphasia speech keyword classification. When applied to attention-based CNN models, these techniques generate more focused, class-specific heatmaps, providing a deeper understanding of model behaviour, particularly in noisy and impaired speech. Our results demonstrate that these enhanced Grad-CAM methods outperform the standard Grad-CAM by offering more detailed and meaningful explanations, which is critical for interpreting models applied to aphasia speech. We compare our approach using qualitative and perturbation-based trustworthiness, infidelity and sufficiency scores as quantitative metrics. Among the techniques, ED-GCAM outperformed all others. The proposed methods significantly improve the accuracy and transparency of speech processing models, with potential suggestions for clinical applications.

Jinhui Cheng, Zhaoliang Guan, Jiangduo Fu et al.

This work provides a comprehensive overview of advanced integration-inspired memory process design, focusing on the integration methods of 2D, 2.5D, and 3D. The integration of compute and memory blocks has demonstrated encouraging outcomes in enhancing memory access latency and energy efficiency for data-centric operations. The challenges and future prospects for PIM design include addressing trade-offs in the integration process, thermal management in highly integrated 3D designs, developing design automation tools for 3D designs, and identifying practical application scenarios for PIM to maximize its benefits. The use of through-silicon vias (TSVs) technology enables the efficient design of 3D structures with improved bandwidth density, while hybrid bonding technology shows advantages in achieving higher interconnect density and data transmission bandwidth. Monolithic integration represents a distinctive solution for high-density module integration, whereby custom circuit layers are stacked vertically in a single chip. This approach represents an efficient alternative to traditional 2D integration technologies. These advances in integration technology provide a roadmap for the future of PIM design and its application in real-world scenarios. In conclusion, the continuous development and integration of different technologies in PIM design has the potential to significantly enhance performance, energy efficiency, and integration density for data-centric tasks.

Guozheng Zhang, Shuo Wang, Chen Li et al.

A modular multilevel converter (MMC) can generate different common-mode voltage (CMV) values due to the high-frequency changing of the switching state under various modulation strategies. The high-frequency dv/dt will produce common-mode current in the equivalent common-mode loop to the ground, which will affect the insulation and shorten the life of the equipment. To eliminate the effect of common-mode voltage on MMC operation, a common-mode voltage elimination strategy (0CMV-SVPWM) is proposed for five-level MMC space vector pulse width modulation (SVPWM) by using the vector that does not generate common-mode voltage as the reference vector in this paper. The proposed strategy is studied and analyzed by the rapid prototype development experimental system based on RT-LAB to verify the feasibility and effectiveness of the proposed strategy.

Johannes L. Otto, Lukas M. Sauer, Malte Brink et al.

Nickel-based filler metals are frequently used in high temperature vacuum diffusion brazing for austenitic stainless-steel joints when components are subjected to high static or dynamic loads, corrosive environments and elevated temperatures. Due to melting point depressing metalloids such as silicon and boron, hard and brittle intermetallic phases are formed during the brazing process depending on the diffusion mechanisms. These brittle phases significantly affect mechanical and corrosive properties of the compounds. To quantify the influences of their amount, morphology and distribution, deep learning image segmentation was applied to segment these phases of the athermal solidification zone and the diffusion zone. Subsequently, characteristic microstructure parameters were calculated from these. The parameters of six different brazed joint variations were compared with their experimental characterization of mechanical and corrosive properties so that several correlations could be identified. Finally, a layer-by-layer removal of a brazed joint was performed using a focused ion beam, and a 3D model was reconstructed from the generated images to gain a mechanism-based understanding beyond the previous 2D investigations.

D.Z. Fu, T.J. Yang, Y.J. Pan et al.

In China’s goal of reaching carbon neutrality by 2060, the blending-biofuel-based heating technique is being used to reduce CO2 and air-pollutant emissions in existing district heating systems in northern China. This brings a series of new system components, complex interactions, and multiple-polymorphic uncertainties to the heating systems, making it difficult for the heating-system manager to improve the traditional fuel management mode while considering the demands of society, economy, policy, environment, and system operation. To address this issue, this study proposes an inexact multi-recourse hybrid-fuel management model for a biofuel-penetrated district heating system (BDHS). The model minimizes the total heating cost by optimizing the biofuel blending ratio, coal and biofuel deficit-recourse pattern among different heating sources, and selecting the optimal CO2 reduction mode under uncertainties. An application of the model to a BDHS case in Dalian City shows that the 5% biofuel blending ratio is suitable for both main heating sources and that the 0 deficit of high-quality coal can be up to [2.48, 2.69] × 103 tonne with the “cold-degree” changing from “mild” to “cold”. The results also indicate that the proposed model can ensure biofuels and high-quality coal are not overused or misused, but instead consumed responsibly. Additionally, most of the CO2 produced in the pulverized coal boiler is traded, while most of the CO2 sourced from the circulating fluid bed boiler is treated by the chemical absorption equipment. Finally, the model reveals that a high system cost (up to [84.73, 96.83] × 106 CNY) and low CO2 emission (down to [66.13, 78.07] × 103 tonne) can be obtained at a high thermalization coefficient through the tradeoff analysis.

Xiaoling Wei, Yongbao Feng, Xiaoxia Han et al.

At present, with the continuous development and great improvement of mechanical manufacturing, processing, and assembly technology, mechanical flow-induced vibration (FIV) with a relatively concentrated frequency domain can be controlled by active and passive noise reduction methods. However, whether it is active noise reduction or passive noise reduction, they all focus on how to suppress the transmission of sound waves and cannot solve the problems of flow leakage, obvious temperature rise, and noise excitation from the root cause. Therefore, it is necessary to determine the location of the primary and secondary excitation sound sources of FIV, the identification of true and false sounds, and the characteristic relationship between flow and noise. This provides a theoretical basis and engineering application direction for the mechanism of noise reduction of FIV. The numerical calculation part of the acoustics in this paper is solved by the hybrid method, and the flow field is discretely calculated by the large eddy simulation (LES) module in the Fluent software. When the calculated flow field is stable, the velocity field of one impeller rotation period is selected to be output as the iterative value of the sound field and imported into ACTRAN for Fourier transform. Then, the sound field calculation is carried out, and the result of the spatial and temporal variation of the sound field is finally obtained. Through experiments, it was found that when the load of the gear pump is 8 MPa, the volumetric efficiency of the optimized circular-arc helical gear pump of the sliding bearing was improved by about 4%. When the rotation speed is 2100°r/min, the arc helical gear pump reduced the surface temperature rise by 2.5°C. This verified that the optimized performance of the sliding bearing in the arc helical gear pump is significantly improved. Through the theoretical model of the temperature rise of the sliding bearing, the phenomenon that the surface temperature of the prototype gear pump was not significantly increased with the loading in the low pressure region is explained.

Shijia Liu, Ayse Ay, Qiaochu Luo et al.

The integration of non-enzymatic glucose sensing entities into device designs compatible with industrial production is crucial for the broad take-up of non-invasive glucose sensors. Copper and its oxides have proven to be promising candidates for electrochemical glucose sensing. They can be fabricated in situ enabling integration with standard copper metallisation schemes for example in printed circuit boards (PCBs). Here, copper oxide electrodes are prepared on flexible polyimide substrates through direct annealing of patterned electrode structures. Both annealing temperature and duration are tuned to optimise the sensor surface for optimum glucose detection. A combination of microscopy and spectroscopy techniques is used to follow changes to the surface morphology and chemistry under the varying annealing conditions. The observed physico-chemical electrode characteristics are directly compared with electrochemical testing of the sensing performance, including chronoamperommetry and interference experiments. A clear influence of both aspects on the sensing behaviour is observed and an anneal at 250 °C for 8 h is identified as the best compromise between sensor performance and low interference from competing analytes.

K. Azizi, Y. Sarac, H. Sundu

Abstract The LHCb Collaboration recently reported the observation of a new excited bottom baryon Ξ b (6227)0 and announced an improvement in the measurements related to the previously observed Ξ b (6227) − state. We conduct an analysis for Ξ b (6227)0 state considering it as isospin partner of the Ξ b (6227) − resonance and possibly 1P or 2S excited state with spin J = 3 2 $$ \frac{3}{2} $$ . The corresponding masses for both possibilities have consistent results with the experimental data, indicating that only with the mass sum rules, one can not make exact decision on the nature and quantum numbers of this state. To go further, the decays of these possible excited states to Ξ b − π + $$ {\Xi}_b^{-}{\pi}^{+} $$ final state are also considered and the relevant strong coupling constants are extracted from the light cone sum rules. The obtained decay width values support the possibility of Ξ b (6227)0 to be the 1P excited state of Ξ b (5945)0 baryon.

USMAN, A., CHOUDHRY, M. A.

Static Transfer Switch (STS) is required for high-speed transfer of essential load to the alternate power source when the main source fails due to power disturbance (PD). A fast and accurate PD detection method is required to ensure transfer time recommended by Computer Business Equipment Manufacturers Association (CBEMA) and IEEE Std. 446. This study encompasses the machine learning technique to reduce detection time for the disturbance on the preferred source. The 10 sample frames of acquired voltage signal were first differentiated and then distinctive features, i.e., Mean Absolute Deviation (MAD) and Energy (E) were extracted from the resultant frames. The features were fed to the Linear Support Vector Machine (L-SVM) classifier to detect the occurrence of PD events. The proposed approach achieved 100% accuracy for PD detection and detection time was significantly reduced. The system is robust in terms of unbalanced and marginal PDs. The system was validated using both simulated and real voltage signals. The proposed algorithm is easy to implement on an embedded system. Hence, detection time according to STS requirements can be achieved under various power system conditions.

Hua Zhang, Taojian Fan, Wen Chen et al.

Smart drug delivery nano-systems show significant changes in their physical or chemical properties in response to slight change in environmental physical and/or chemical signals, and further releasing drugs adjusted to the progression of the disease at the right target and rate intelligently. Two-dimensional materials possess dramatic status extend all over various scientific and technological disciplines by reason of their exceptional unique properties in application of smart drug delivery nano-systems. In this review, we summarized current progress to highlight various kinds of two-dimensional materials drug carriers which are widely explored in smart drug delivery systems as well as classification of stimuli responsive two-dimensional materials and the advantages and disadvantages of their applications. Consequently, we anticipate that this review might inspire the development of new two-dimensional materials with smart drug delivery systems, and deepen researchers’ understanding of smart nano-carries based on two-dimensional materials.

Iván Pérez Mallea, Lidia Ruiz Ortiz

Desde su surgimiento, la Universidad de las Ciencias Informáticas ha conferido vital importancia a la asimilación de las Tecnologías de la Información y la Comunicación en todos sus procesos sustantivos. Desde el año 2002 que dio comienzo la asimilación de dichas tecnologías en el proceso de enseñanza aprendizaje hasta la actualidad el camino transitado ha sido largo y lleno de experiencias. En el presente trabajo se describen las etapas de la evolución del Ecosistema Digital de Aprendizaje en la Universidad de las Ciencias Informáticas presentándolo desde su surgimiento hasta la actualidad, así como algunas perspectivas para el enriquecimiento del mismo.

Maral Rahimzadeh, Majid Sadeghizadeh, Farhood Najafi et al.

During the last few decades, extensive studies have been conducted to elucidate the anti-cancer effects of curcumin. Despite promising results indicating curcumin could impede cancer cells ability thrive and proliferation, clinical applications of it have been limited. This limitation is mainly due to low solubility, poor bioavailability, rapid metabolism, and deficient absorption. To improve the physiochemical properties of curcumin, we have synthesized a novel biodegradable gemini surfactant in which curcumin molecules were entrapped. Gemini surfactant-curcumin nanocapsules were prepared using nanoprecipitation method and characterized by several techniques including, DLS, TEM, AFM, FTIR, DSC and XRD. The in vitro MTT assay, cellular uptake, and apoptosis assay were performed using MDA-MB-231 cell line. The gemini surfactant molecules were able to form vesicles in aqueous solution with a narrow size distribution (PDI  $\cong $  0.3). An encapsulation efficiency of 87.45 ± 2.3% and the drug loading content of 4.98 ± 0.12% were acquired. Curcumin molecules were dispersed in the hydrophobic shell of the vesicles, and sustained release profile was observed. Due to the increased cellular uptake and sustained release profile, the gemini surfactant-curcumin nanocapsules exhibited higher cytotoxicity and enhanced apoptosis in MDA-MB-231 cells compared to free curcumin. The results indicate that gemini surfactant-curcumin complex shows considerable promise as an anti-breast cancer drug.

Gaurav Pandey, Ankit Vora

A wide range of medical devices have significant electronic components. Compared to open-source medical software, open (and open-source) electronic hardware has been less published in peer-reviewed literature. In this review, we explore the developments, significance, and advantages of using open platform electronic hardware for medical devices. Open hardware electronics platforms offer not just shorter development times, reduced costs, and customization; they also offer a key potential advantage which current commercial medical devices lack—seamless data sharing for machine learning and artificial intelligence. We explore how various electronic platforms such as microcontrollers, single board computers, field programmable gate arrays, development boards, and integrated circuits have been used by researchers to design medical devices. Researchers interested in designing low cost, customizable, and innovative medical devices can find references to various easily available electronic components as well as design methodologies to integrate those components for a successful design.

Yunlong Ding, Jialian Shi, Dongying Ju

In this study, magnesium alloy AZ91, which was cast by double roll casting system, was rolled by a rolling mill. Then, rolled magnesium alloy and magnesium alloy without being rolled were, respectively, welded with aluminum alloy 6061 by diffusion bonding method. Furthermore, annealing process was applied to refine the microstructure and improve mechanical property. The microstructure and elemental distribution of diffusion zone were investigated with a scanning electron microscope (SEM), an electron probe micro analyzer (EPMA), and a transmission electron microscope (TEM). In addition, hardness and tensile strength were measured. When cast magnesium alloy was used, the width of diffusion layers was wider than that with rolled magnesium alloy. And the width increased with the increasing annealing temperatures. Element distribution of specimens with annealing was more uniform than that did not undergo annealing process. Furthermore, tensile strength turns to be strongest after annealing at 250°C. And the strength of the specimens with rolled magnesium alloy was stronger than that with cast magnesium alloy which was not rolled.

王彤, 曾彦珺, 李怡 et al.

作为雷电活跃地区,海南电网的雷击跳闸事故较为频繁,防雷保护成为了关键问题。针对一起福山变电站220 kV母线相继雷击故障进行了研究,根据现场情况和故障录波数据表明,故障原因是雷击造成220 kV母线的3号母线C相和2号母线A相先后发生接地短路故障,同时并联电容器处在运行状态造成福港线电压升高。利用EMTP建立了系统等值模型,分析了福港线过电压的原因以及并联电容器对于母线过电压的影响,研究表明故障工况下福港线过电压已经超过了保护定值,而且投入并联电容器会造成母线过电压的升高。最后提出了相应的解决措施:重新进行绝缘配合的设计,对于220、500 kV母线,建议装设氧化锌避雷器,开展适合于特殊地理环境的防雷新技术研究。

Ruthilene Catarina Lima da Silva, Clodomiro Alves Júnior, Jorge Reinaldo Oliveira Neves et al.

This study aimed to obtain a bifunctional fabric from the point of view of hydrophilicity/hydrophobicity for biomedical applications. To achieve this, both sides of a fabric of polylactic acid (PLA) were subjected to a plasma treatment. While in a side the oxygen was introduced to the other side, simultaneously, was added methane. The plasma treatment was performed at 100 W, 1.8 mbar, during 30 minutes. By Scanning Electron Microscopy (SEM) morphological analysis, it became evident that the fabric side facing the oxygen inlet showed micropittings, while the reverse side had smooth surfaces. Analysis by X-Ray photoelectron spectroscopy (XPS) revealed an increase in the amount of oxygen in the surface of the PLA on both sides of the fabric. The surface function was characterized by measurements of water absorption rate, where it was determined that one fabric side was more hydrophilic than the other side. The results indicated achievement of a bifunctional fabric through orientation of working gases during a plasma treatment.

Lasni Julita Siahaan

Fasilitas internet yang dibangun dengan proyek USO adalah suatu teknologi baru yang dapat menimbulkan reaksi pada penggunanya, baik reaksi menerima maupun reaksi menolak. Oleh karena itu, perlu diketahui model penerimaan teknologi tersebut serta factor-faktor yang berpengaruh terhadap penerimaanya. Salah satu model penerimaan pemakai terhadap teknologi yang paling sesuai sampai sekarang adalah technology acceptance model (TAM) yang dikemukakan oleh Davis dan Khosrow-Pour (2006: 209). Bagaimana kecocokan model TAM dalam menilai penerimaan pengguna terhadap fasilitas internet tersebut dianalisis dengan structural equation modeling (SEM). Pendekatan dalam penelitian ini adalan kuantitatif dengan melakukan survey kepada masyarakat di sekitar lokasi pembangunan proyek USO di Propinsi Jawa Tengah. Hasil penelitian menunjukkan bahwa model TAM dapat digunakan menilai perilaku masyarakat di sekitar lokasi pembangunan proyek USO dalam menerima dan memanfaatkan fasilitas Internet.

张龙光, 周渊平, 谢宁 et al.