Electrical Ground Research Articles

Cooperative scheduling of airport ground electric service vehicles considering workload balance: A column generation approach

Cooperative scheduling of airport ground electric service vehicles considering workload balance: A column generation approach

Enhancing Chemoselectivity of On-Surface Reactions on Reconstructed Au(110): The Case of a Pentalene-Bridged Polyacene Analogue.

Polyacene analogues, consisting of short acene segments separated by nonbenzenoid rings, offer intriguing electronic properties and magnetic interactions. Pentalene-bridged polyacenes (PPs), in particular, hold promise for enhancing the electrical conductivity and potential open-shell ground states. However, PPs have remained elusive in solution chemistry due to poor solubility and limited synthetic protocols. Here, we report the on-surface synthesis of PPs through the annulation between ortho-xylene groups. Scanning tunneling microscopy and atomic force microscopy reveal that the reconstructed Au(110) surface significantly enhances the chemoselectivity of the annulation process. Scanning tunneling spectroscopy combined with density functional theory suggests that PP exhibits a narrow direct band gap, similar to long acenes. This work demonstrates the potential for band structure engineering in polyacene analogues by incorporating nonbenzenoid rings, paving the way to advancements in organic electronics and spintronics.

Robust adaptive control of uncertain electric ground vehicles using $${{\mathcal {L}}}$$1 theory and projection algorithm

Robust adaptive control of uncertain electric ground vehicles using $${{\mathcal {L}}}$$1 theory and projection algorithm

Design Requirements for the Device for Differentiating Pathological States of Biological Tissues

The appearance of the device for mini-gamma-quantum differentiation of biological tissues, the arrangement of units (research unit and control unit), units (cassette holder, electronic units, etc.) and individual parts (cassette, etc.), as well as control panels (front and rear) have ergonomic indicators that ensure convenience use (preparation for operation – ease of installation of the device on the table, connection to the electrical network and grounding, loading/unloading of biological tissue samples into/from the cassette, etc.); ease of use (ease of working with the control panel and the cassette with the cassette holder); the convenience of preventive maintenance work (cassette disinfection, etc.). The control unit and the research unit are located in different housings of the device: a) control unit – in a high-strength plastic case; b) research unit – in a stainless steel metal case. A measuring device in the form of a scintillation detector is located in the metal case of the research unit, consisting of: a case, a scintillator (crystal, plastic, liquid), a photoelectric multiplier, a power cell, a source of ionizing low-energy gamma radiation in a special protective case that ensures compliance with sanitary requirements and radiation safety standards, and a cassette for biological tissue to be examined (a sample of biological tissue is placed in the biopsies section of the cassette), which is installed in the cassette holder. The design of the cassette holder includes a knife for cutting excess biopsies. The cassette holder is firmly fixed in the housing of the device's research unit. The control unit houses power elements, a microprocessor controller for processing information and maintaining a database, providing communication with peripheral electronic devices. The front panel of the device houses the information monitor and control points. On the back panel there is a device on/off switch, a fuse and places for connecting additional devices. The device has the possibility of applying protective grounding.

Solid-State Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Next-Generation Sustainable Electric Aviation

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system that meets rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for the safe operation of commercial electric aero vehicles. The SABERS concept proposes a battery that meets the critical performance criteria by developing a solid-state architecture battery utilizing a high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed using NASA-patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement for the highly flammable liquid organic electrolytes currently in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed in a serial stacking configuration to enable the dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, the optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C, providing the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. The SABERS team employed novel materials development, computational modeling, and design-of-experiments (DOE) optimization studies in their research. This presentation will show the results of these studies and demonstrate a feasible path for solid-state cells with a specific energy greater than 400 Wh/kg to enable electric aircraft. Figure 1

Systematic investigation of structural, magneto-electronic, mechanical, thermophysical, optical and thermoelectric properties of Hf2VZ (Z = Ga, In, Tl) inverse Heusler alloy for spintronics applications

The structural stability, magneto-electronic, mechanical, thermodynamic, thermoelectric and optical, characteristics of the Hf2VZ (Z = Ga, In, Tl) Heusler alloy are revealed and understood by a comprehensive investigation employing density functional theory simulations. The stability of these alloys in F-43m phase is confirmed by structural optimizations and cohesive energies, which also provide the equilibrium lattice parameters. Compared to generalized gradient approximations, modified Becke–Johnson methods were more effective in determining the electrical structure and ground state attributes. Hf2VZ (Z = Ga, In, Tl) is predicted to have half-metallic ferromagnetic characteristics with indirect spin-up gaps based on the band structure analysis and density of state calculations. Stability of these compounds is determined by calculating the elastic constants indicating the ductile nature of these alloys. The quasi-harmonic Debye model is used to predict the effects of temperature and pressure on thermodynamic characteristics, conveying the alloys' thermodynamic stability. To estimate the thermoelectric performance of these materials, we compute electrical conductivities and Seebeck coefficients. The optical parameters like absorption coefficient, optical conductivity, dielectric constants etc., were determined to show the photo-voltaic applications of these alloys. Hence, the finding will lead to future research on developing new types of Hafnium based Heusler alloys for spintronics, thermoelectric and optoelectronics applications.

Analisis Sistem Instalasi Listrik Pada Menara Transmisi Telekomunikasi di Kota Makassar

This research is a quantitative study using survey methods aimed at determining the viability of electrical installations on telecommunications transmission towers. The research was conducted at UPD007 Telkomas, Makassar City, South Sulawesi Province. The variables in this study are the security of electrical installations, transmitters of electric installations and grounding of electricity installations. Data collection techniques are observation, documentation, interview and measurement techniques. Data analysis techniques used are descriptive data analysis using Persyaratan Umum Instalasi Listrik (PUIL) 2011. The results of the research show that the use of the security of the electrical installation at each point is said to be appropriate based on its type and capacity. The transmitter of the electrical installation used in its entirety is said to be valid based on the peripheral area, whereas the color of the transmitter indicates only the entire neutral transmitter, grounded transmitter and DC transmitter conforming to the standard using Persyaratan Umum Instalasi Listrik (PUIL) 2011. The grounding resistance obtained on each protection is fully said to be eligible under the provisions of Persyaratan Umum Instalasi Listrik (PUIL) 2011.

Topographic ridges express late Quaternary faulting peripheral to the New Madrid seismic zone, intraplate USA: Their tectonic implications

Topographic ridges express late Quaternary faulting peripheral to the New Madrid seismic zone, intraplate USA: Their tectonic implications

A IMPORTÂNCIA DO ATERRAMENTO ELÉTRICO NA SEGURANÇA E EFICIÊNCIA DE SISTEMAS ELÉTRICOS

The following work will propose the electrical grounding, the voltage and the way in which electrical grounding is used and its proper installation tends to promote an impact on user safety, minimizing accidents, as most users do not know what the system is or even what the Fundamentals are for, the general objective of this article is to understand electrical grounding and how its performance contributes to user safety and as a secondary objective: Importance of grounding, types of grounding, materials and devices, basic principles and technical standards. The methodology used was bibliographic research, using sources such as books, magazines, theses, and publications on the internet, allowing the researcher to access existing material on the subject, being of the qualitative type. The results and discussion demonstrate the importance of electrical grounding for the safety and protection of electrical infrastructure, thus providing important details that can improve system efficiency and maintain safety, as well as regulatory standards. The conclusion is that electrical grounding plays a crucial and important role in safety and protection, so it is better to use the TN-S grounding system because the protective conductor will always be at zero potential.

Flexible and Transparent Electrovibration-Based Haptic Display with Low Driving Voltage.

Electrovibration haptic technology, which provides tactile feedback to users by swiping the surface with a finger via electroadhesion, shows promise as a haptic feedback platform for displays owing to its simple structure, ease of integration with existing displays, and simple driving mechanism. However, without electrical grounding on a user's body, the frequent requirement of a high driving voltage near 50 V limits the use of electrovibration haptic technology in practical display applications. This study introduces materials and fabrication strategies that considerably reduce the driving voltage. We used a transparent poly(vinylidene fluoride) (PVDF) thin film deposited on transparent conductive polymers through a simple spin-coating process, thereby enabling easy integration with existing display technologies. The high dielectric constant characteristics of PVDF enabled the production of tactile cues at low voltages (approximately 15 V), which are within the safety limits of common electronics. We verified the feasibility of our electrovibration haptic feedback system on the basis of the absolute threshold voltage through two-alternative forced choice psychological tests. The results revealed that the PVDF dielectric layer exhibited a relatively lower absolute threshold than commonly used polymer films, which possess a relatively lower dielectric constant. To validate the tactile attributes, a Likert five-point scale survey was conducted, considering flat, concave, and convex curvatures. The results indicated that our haptic device can render diverse surface textures, such as "hairy" and "groovy", on the fingertips through the control of applied pulse width modulated voltage signals.

An Integrated Hydrogeophysical Approach for Unsaturated Zone Monitoring Using Time Domain Reflectometry, Electrical Resistivity Tomography and Ground Penetrating Radar

Continuous measurements of soil moisture in the deeper parts of the unsaturated zone remain an important challenge. This study examines the development of an integrated system for the continuous and 3-D monitoring of the vadose zone processes in a cost- and energy-efficient way. This system comprises TDR, ERT and GPR geophysical techniques. Their capacities to adequately image subsurface moisture changes with continuous and time-lapse measurements are assessed during an artificial infiltration experiment conducted in a characteristic urban site with anthropogenic fills and much compaction. A 3-D array was designed for each method to expand the information of a single TDR probe and obtain a broader image of the subsurface. Custom spatial TDR probes installed in boreholes made with a percussion drilling instrument were used for soil moisture measurements. Moisture profiles along the probes were estimated with a numerical one-dimensional inversion model and a standard calibration equation. High conductivity water used during all infiltration tests led to the detection of the flow by all techniques. Preferential flow was present throughout the experiment and imaged sufficiently by all methods. Overall, the integrated approach conceals each method’s weaknesses and provides a reliable 3-D view of the subsurface. The results suggest that this approach can be used to monitor the unsaturated zone at even greater depths.

A bottom-up approach for greenhouse gas emission estimation at the community level: A case study in Japan

A bottom-up approach for greenhouse gas emission estimation at the community level: A case study in Japan

Simultaneous measurements of temporal evolutions of the voltage and the current on the load of the Seoul National University X-pinch device using the optics-based systems.

Optics-based measurement systems have been developed to measure the voltage and the current on a load of the Seoul National University X-pinch device [Ryu etal., Rev. Sci. Instrum. 92, 053533 (2021)]. A lithium niobate crystal that changes the polarization state of the propagating laser beam due to the Pockels effect induced by the electric field across the crystal, thus capable of measuring the voltage, is located next to the load. For the current measurement, an optic fiber is wound around the load to detect the change in the polarization state of the propagating laser beam due to the Faraday rotation induced by the magnetic field. As both voltage and current measurement systems utilize optical effects, the sensors, i.e., the lithium niobate crystal and the optic fiber, do not require any electrical grounds, in contrast to circuit-based probes, such as voltage dividers or Rogowski grooves. This facilitates an easy access to shield other required electronic devices, such as lasers and photodetectors, from the electromagnetic interference generated by the X-pinch power system. In addition, the sensors can be placed in close proximity to the load with fewer concerns on the electrical insulation. Temporal evolutions of the simultaneously measured voltage and current on the load of the X-pinch are successfully obtained and discussed.

Development and Testing of a Gas Turbine Test Rig Setup for Demonstrating New Aviation Propulsion Concepts

To further increase efficiency and to significantly reduce climate impact in the aviation sector, new propulsion concepts must be developed. As full electrification in mid- and long-range aviation is impractical due to the low gravimetric energy density of batteries, new approaches must be developed. Therefore, the so-called hybrid electric ground demonstrator (HeBo), equipped with a Rolls Royce M250-C20B gas turbine is set up. The test rig serves as a development platform for various new gas turbine-based propulsion concepts for aviation, such as hybrid electric concepts or a novel cycle concept with steam injection to the combustor, which are described in this paper. The main focus of the work is on the experimental setup and the commissioning of the baseline test rig. This will place the test rig in the context of current research activities and serve as reference for subsequent research results.

The “Annunziata” Garden in Cammarata (Sicily): Results of integrated geophysical investigations and first archaeological survey

The “Annunziata” Garden in Cammarata (Sicily): Results of integrated geophysical investigations and first archaeological survey

A Simple Method to Manufacture a Force Sensor Array Based on a Single-Material 3D-Printed Piezoresistive Foam and Metal Coating.

Nowadays, 3D printing is becoming an increasingly common option for the manufacturing of sensors, primarily due to its capacity to produce intricate geometric shapes. However, a significant challenge persists in integrating multiple materials during printing, for various reasons. In this study, we propose a straightforward approach that combines 3D printing with metal coating to create an array of resistive force sensors from a single material. The core concept involves printing a sensing element using a conductive material and subsequently separating it into distinct parts using metal-coated lines connected to the electrical ground. This post-printing separation process involves manual intervention utilizing a stencil and metallic spray. The primary obstacle lies in establishing a sufficient contact surface between the sprayed metal and the structure, to ensure effective isolation among different zones. To address this challenge, we suggest employing a lattice structure to augment the contact surface area. Through experimental validation, we demonstrate the feasibility of fabricating two sensing elements from a single-material 3D-printed structure, with a maximum electrical isolation ratio between the sensors of above 30. These findings hold promise for the development of a new generation of low-tech 3D-printed force/displacement sensor arrays.

On the question of electrical safety in physiotherapy rooms: protective grounding of electrical equipment

Abstract. The article discusses current issues of electrical safety in medical and preventive organizations. Goal: to attract the attention of physiotherapy specialists to the correct organization of protective grounding as the main means of preventing electrical injuries. Material and research: modern regulatory framework for the technical operation of electrical installations of electrical energy consumers in medical premises, the selection and use of electrical equipment and grounding devices, the frequency of inspections, measurements and tests, passports of grounding devices. Conclusion. It seems important to carry out measures to prevent accidents during the operation of physiotherapeutic equipment in each physiotherapy unit. To increase the level of organization of work on electromedical devices. Exclude the admission of personnel to the work of paramedical personnel without mandatory verification of the implementation of organizational and technical measures in the preparation of workplaces. Health care facilities should regularly hold occupational safety days, during which health care personnel should learn cardiopulmonary resuscitation skills, which today can be done in multidisciplinary accreditation and simulation centers of medical universities and academies.

The effect of electron backscatter and charge build up in media on beam current transformer signal for ultra-high dose rate (FLASH) electron beam monitoring

Objective. Beam current transformers (BCT) are promising detectors for real-time beam monitoring in ultra-high dose rate (UHDR) electron radiotherapy. However, previous studies have reported a significant sensitivity of the BCT signal to changes in source-to-surface distance (SSD), field size, and phantom material which have until now been attributed to the fluctuating levels of electrons backscattered within the BCT. The purpose of this study is to evaluate this hypothesis, with the goal of understanding and mitigating the variations in BCT signal due to changes in irradiation conditions. Approach. Monte Carlo simulations and experimental measurements were conducted with a UHDR-capable intra-operative electron linear accelerator to analyze the impact of backscattered electrons on BCT signal. The potential influence of charge accumulation in media as a mechanism affecting BCT signal perturbation was further investigated by examining the effects of phantom conductivity and electrical grounding. Finally, the effectiveness of Faraday shielding to mitigate BCT signal variations is evaluated. Main Results. Monte Carlo simulations indicated that the fraction of electrons backscattered in water and on the collimator plastic at 6 and 9 MeV is lower than 1%, suggesting that backscattered electrons alone cannot account for the observed BCT signal variations. However, our experimental measurements confirmed previous findings of BCT response variation up to 15% for different field diameters. A significant impact of phantom type on BCT response was also observed, with variations in BCT signal as high as 14.1% when comparing measurements in water and solid water. The introduction of a Faraday shield to our applicators effectively mitigated the dependencies of BCT signal on SSD, field size, and phantom material. Significance. Our results indicate that variations in BCT signal as a function of SSD, field size, and phantom material are likely driven by an electric field originating in dielectric materials exposed to the UHDR electron beam. Strategies such as Faraday shielding were shown to effectively prevent these electric fields from affecting BCT signal, enabling reliable BCT-based electron UHDR beam monitoring.

Electrical Ground Fault Monitoring System Utilizing Arduino and Android Application

Abstract: The increasing residential fire incidence caused by electrical ground faults worldwide challenges present and future researchers to develop a system capable of mitigating its occurrence. The absence of periodic equipment maintenance and monitoring facilities leads to potential electrical hazards to humans and properties. However, technological advances have made online electrical ground fault monitoring equipment possible. Users can now remotely gain information regarding the operational condition of electrical equipment in their homes. This paper presents the developed Electrical Ground Fault Monitoring System using Arduino with Android Application (EGFMSAAA), which can detect and transmit electrical ground fault parameters and safety precautions. This study developed a ground fault detector and a mobile application for the monitoring system.

Revealing Subtle Active Tectonic Deformation: Integrating Lidar, Photogrammetry, Field Mapping, and Geophysical Surveys to Assess the Late Quaternary Activity of the Sava Fault (Southern Alps, Slovenia)

We applied an interdisciplinary approach to analyze the late Quaternary activity of the Sava Fault in the Slovenian Southern Alps. The Sava Fault is an active strike-slip fault, and part of the Periadriatic Fault System that accommodated the convergence of Adria and Europe. It is one of the longest faults in the Southern Alps. Using high-resolution digital elevation models from lidar and photogrammetric surveys, we were able to overcome the challenges of assessing fault activity in a region with intense surface processes, dense vegetation, and relatively low fault slip rates. By integrating remote sensing analysis, geomorphological mapping, structural geological investigations, and near-surface geophysics (electrical resistivity tomography and ground penetrating radar), we were able to find subtle geomorphological indicators, detect near-surface deformation, and show distributed surface deformation and a complex fault pattern. Using optically stimulated luminescence dating, we tentatively estimated a slip rate of 1.8 ± 0.4 mm/a for the last 27 ka, which exceeds previous estimates and suggests temporal variability in fault behavior. Our study highlights the importance of modern high-resolution remote sensing techniques and interdisciplinary approaches in detecting tectonic deformation in relatively low-strain rate environments with intense surface processes. We show that slip rates can vary significantly depending on the studied time window. This is a critical piece of information since slip rates are a key input parameter for seismic hazard studies.