Wire Connections Research Articles

Orthogonal‐Based Reconfigurable Light‐Controlled Metasurface for Multichannel Amplitude‐Modulation Communication

AbstractOptical‐control reconfigurable metasurfaces can avoid crosstalk between microwave signal and direct current (DC) signal caused by physical wire connection, which paves a paradigm for dynamically and remotely controlling electromagnetic (EM) wave. However, the traditional light‐controlled reconfigurable metasurfaces mainly focus on the modulation of single polarized EM wave, which is difficult to adapt to the modulation of various signals in communication. In this work, a photoresistor is fully embedded into the meta‐atom as an active device, and a light‐controlled reconfigurable metasurface (LCRM) with multi‐polarization amplitude modulations is proposed. The designed metasurface controls the luminous intensity of light emitting diode (LED) array through computer, and then adjusts the photoresistor value, which can achieve amplitude modulations. In order to verify the feasibility and effectiveness of the proposed framework, the metasurface is simulated, fabricated, and measured, and the measurement results are basically consistent with the theoretical simulation results. Based on the EM characteristics of the designed metasurface, linear polarized (LP) wave synthesis and information transmission are carried out to demonstrate the design. This work designs an amplitude modulation metasurface under orthogonal‐polarization wave incidence to expand the LCRM application, which has broad development prospects in many fields such as information transmission, communication systems, and holographic imaging.

Comparative Study on the Efficiency of Wireless Charging Structures

With the increasing popularity of various electronic devices, people's demand for the portability of device charging is also increasing. Wireless charging technology has emerged and is showing a rapid development trend. Wireless charging technology utilizes the conversion effect of electric and magnetic fields, transmitting electrical energy wirelessly from the transmitting end to the receiving end, charging the battery of the receiving device. There is no need for a wire connection between the charging device and the electrical device, and the charging device and the electrical device's conductive contact points can be fully enclosed. This paper first introduces the origin and development of wireless charging technology. Then, it introduces the mainstream standards of wireless charging technology. The author mainly analyzes the structure and principle of two types of wireless charging technologies: electromagnetic induction and resonant. Then, it compares the two types of wireless charging technologies in terms of principle and transmission parameters. This paper summarizes the characteristics of both technologies above.Finally, it summarizes the application scenarios of wireless charging technology. This paper aims to provide literature support for the research on wireless charging technology.

A thermal insulation microactuator for Braille display using paraffin wax/carbon nanotube composite with induction heating

A new thermal insulation microactuator for Braille display using a phase change material (PCM) composite with induction heating is proposed. The PCM composite is prepared by fully mixing paraffin with multi-walled carbon nanotubes (MWCNTs), which is mainly used as both electrically and thermally conductive enhancer. As a result of that, the PCM composite is conductive and a wireless induction heating can be realized with the paraffin composite, which avoids the connection of wires from the inner chamber with a relatively simple fabrication process. In order to prevent the penetration of the paraffin from the elastic film, a solvent-resistant TPU diaphragm is adopted to seal the PCM chamber. In addition, thermal insulation between the higher temperature of PCM and the finger contact is designed by adding the PDMS diaphragm with PDMS pins. When the input power is 1.29[Formula: see text]W at AC frequency of 1[Formula: see text]kHz, the actuation height of the Braille dot reaches 259[Formula: see text][Formula: see text]m within 7[Formula: see text]s. The microactuator for Braille display presented in this paper has the advantages of short response time, thermal isolation, simple fabrication, small size and low cost.

Mechanism and Control Strategies for Current Sharing in Multi-Chip Parallel Automotive Power Modules

Multi-chip parallel power modules are highly favored in applications requiring high capacity and high switching frequency. However, the dynamic current imbalance between parallel chips caused by asymmetric layouts limits the available capacity. This paper presents a method to optimize dynamic current distribution by adjusting the lengths and connection points of bond wires. For the first time, a response surface model and nonlinear constraint optimization algorithm are introduced, along with parameter analysis based on finite element methods, to establish the response surface models for the parasitic inductance of bond wires and DBC (direct bonded copper). By leveraging the optimization goals for parasitic inductance and the analytical expressions of all response surfaces, the dynamic current sharing issue was transformed into a nonlinear constrained optimization problem. The solution to this optimization problem identified the optimal connection points for the bond wires, enhancing dynamic current sharing performance. Simulations and experiments were conducted, revealing that the optimized automotive-grade module exhibited a significant reduction in current differences between parallel branches, from 41.7% to 5.03% compared with the original design. This indicated that the proposed optimization scheme for adjusting bond wire connection points could significantly mitigate current disparities, thereby markedly improving current distribution uniformity.

(Invited) Gallium Nitride: An Industry Ready Platform for Scalable Artificial Photosynthesis

In this talk, I will present recent advances of artificial photosynthesis utilizing gallium nitride (GaN), which is the second most produced semiconductors next only to silicon. Through nanoscale, quantum, and catalyst engineering, conventional GaN-based semiconductors can be transformed to be highly efficient and stable photocatalyst materials for a broad range of artificial photosynthesis reactions, including solar water splitting, carbon dioxide reduction, methane oxidation, and nitrogen reduction to ammonia. By growing GaN nanostructures under N-rich conditions, the nonpolar surfaces can be transformed to be gallium oxynitride during harsh photocatalysis reaction, which not only protects the surfaces of the light absorber but leads to significantly enhanced photocatalytic and photoelectrochemical performance. Moreover, we have developed unique photocatalytic processes wherein high efficiency solar hydrogen can be produced utilizing tap water, or seawater, without any wire connection, or electricity input. The demonstration of large-scale solar water splitting systems and the performance will be discussed and reported, together with advances in carbon dioxide and nitrogen reduction to clean chemicals and fuels.

Cross-Correlation of Interconnection Technologies—A Case Study of Reduced Wire Bond Quality after Ultrasonic Welding

AbstractIn modern electronic modules, the packing density of components is increasing. This means that the points at which different assembly and connection technologies are used are moving closer and closer together. This significantly increases the probability of mutual interference. The negative effects of later process steps in particular can be critical here. In the present work, a typical case for power electronics production is considered, consisting of thick-wire bonding on the power semiconductor and subsequent ultrasonic welding of load terminals on the same substrate. The effect on the quality of the bond connections was investigated in setups with different load geometries, materials and load intensities. It was found that both wire damage due to cyclic mechanical alternating loading and a change in the interface between substrate and wire occurred. In the case of harder wire materials, complete breakage of the wire connections was observed after just 24 welds on terminals in typical geometries. However, the interface between the wire and the substrate was also damaged and lost 10% of its strength in this case. The investigations show how such effects can be minimized by the choice of wire material and geometry. This is another important building block in holistic process development, taking into account the interactions between different interconnection processes.

An ultrasensitive multimodal intracranial pressure biotelemetric system enabled by exceptional point and iontronics.

The accurate monitoring of vital physiological parameters, exemplified by heart rate, respiratory rate, and intracranial pressure (ICP), is of paramount importance, particularly for managing severe cranial injuries. Despite the rapid development of implantable ICP sensing systems over the past decades, they still suffer from, for example, wire connection, low sensitivity, poor resolution, and the inability to monitor multiple variables simultaneously. Here, we propose an ultrasensitive multimodal biotelemetric system that amalgamates an iontronic pressure transducer with exceptional point (EP) operation for the monitoring of ICP signals. The proposed system can exhibit extraordinary performance regarding the detection of minuscule ICP fluctuation, demonstrated by the sensitivity of 115.95 kHz/mmHg and the sensing resolution down to 0.003 mmHg. Our system excels not only in the accurate quantification of ICP levels but also in distinguishing respiration and cardiac activities from ICP signals, thereby achieving the multimodal monitoring of ICP, respiratory, and heart rates within a single system. Our work may provide a pragmatic avenue for the real-time wireless monitoring of ICP and thus hold great potential to be extended to the monitoring of other vital physiological indicators.

Створення надійних ноутбуків на основі простих змінних компонентів

The subject of study in this article and research is principles of creating of reliable and repairable notebooks. The goal is to determine the structural and circuitral peculiarities of the construction of portable computers and laptops, which improve fault tolerance, repairability, allow possibility of power supply using wider voltage range, and also reduce the cost of repairing, which makes it possible to create more reliable solutions with fault tolerance. The task is to analyze the existing architectures of computers built on modern chipsets; to analyze cases of failure of the computer equipment regarding the causes and consequences of faults; to analyze the possible reasonability of repairing and the computer repair options; to propose recommendations of the structural organization of notebook components and the recommendations for the support of a wide range of notebook voltages of power supply. According to the tasks, the following results were obtained. The analysis of the constructional design features of modern laptops and portable computers is performed. The main components of notebook motherboard, including the processor, multicontroller, and host bridge, are analyzed. The possible causes of faults of system board components are analyzed. The interaction of the multicontroller with BIOS and UEFI of notebooks is analyzed. The causes and solutions of possible issues of battery replacement are identified. The disadvantages of direct wired connection of peripheral devices to the processors implemented as a system on chip are discussed. The recommendations of the creation of repairable circuits of notebooks are proposed. The proposed circuits have a higher cost, weight and size characteristics with higher power consumption, but the obtained fault-tolerance allows the use in critical industries. Conclusions. The scientific novelty of the obtained results is in the fact that the performed analysis of solutions from leading manufacturers and the practical experience of laptop failures diagnostics allowed to propose a set of recommendations of the reliable laptops creation and modification of the existing components including the suppor of a wide range of power supply voltages, that will make it possible the charging from power sources without the use of an additional converters. The proposed use of discrete components and controllers for each interface port for connection of peripheral devices increases the system durability to the influence of external factors with maintaining of workability of the notebook and the rest ports of motherboard in case of the fault of one of them.

Design method of transverse gradient coils based on nonuniform rational B-spline (NURBS) curves.

To propose a hybrid transverse gradient coil design method that leverages current density-based methods and nonuniform rational B-spline (NURBS) curves to optimize the performance and manufacturability of gradient coils. Our method begins by generating an initial wire configuration using a density-based method. Then, we fit NURBS curves to the configuration, and adjust the control parameters of these curves to meet performance requirements. To ensure adequate spacing and even distribution of wires, an objective function utilizing the sigmoid function to modulate the distances between adjacent wires is constructed. Critical factors including gradient efficacy, linearity, eddy current, and torque, are incorporated as constraints. The piecewise nature of the curves provides the flexibility to independently control specific segments without impacting others. We validated our method by designing three shielded transverse gradient coils: a whole-body coil, an ultra-short whole-body coil, and an ultra-short asymmetric head coil. The primary design objectives were to improve linearity and maintain gradient efficiency. All optimized coils demonstrated significant linearity across large diameters of spherical volumes (DSVs), while gradient efficiency, eddy currents, and torque were well-balanced. The objective function effectively managed the wire concentrations required for high linearity, ensuring even wire arrangement and adequate spacing. We leveraged the flexibility of the curves to individually tailor wire paths for specific objectives, such as preventing interference between coils and passive shimming and accommodating wire connections and cooling circuits. This method provides a versatile and effective approach for designing high-performance and manufacturable gradient coils.

Dissimilar Resistance Welding of NiTi Microwires for High-Performance SMA Bundle Actuators

Shape memory alloys (SMAs) are becoming a more important factor in actuation technology. Due to their unique features, they have the potential to save weight and installation space as well as reduce energy consumption. The system integration of the generally small-diameter NiTi wires is an important cornerstone for the emerging technology. Crimping, a common method for the mechanical and electrical connection of SMA wires, has several drawbacks when it comes to miniaturization and high-force outputs. For high-force applications, for example, multiple SMA wires in parallel are needed to keep actuation frequencies high while scaling up the actuation force. To meet these challenges, the proposed study deals with the development of a resistance-welding process for manufacturing NiTi wire bundles. The wires are welded to a sheet metal substrate, resulting in promising functional properties and high joint strengths. The welding process benefits from low costs, easy-to-control parameters and good automation potential. A method for evaluating the resistance-welding process parameters is presented. With these parameters in place, a manufacturing process for bundled wire actuators is discussed and implemented. The welded joints are examined by peel tests, microscopy and fatigue experiments. The performance of the manufactured bundle actuators is demonstrated by comparison to a single wire with the same accumulated cross-sectional area.

Bipolar electrochemical growth of conductive microwires for cancer spheroid integration: a step forward in conductive biological circuitry

The field of bioelectronics is developing exponentially. There is now a drive to interface electronics with biology for the development of new technologies to improve our understanding of electrical forces in biology. This builds on our recently published work in which we show wireless electrochemistry could be used to grow bioelectronic functional circuitry in 2D cell layers. To date our ability to merge electronics with in situ with biology is 3D limited. In this study, we aimed to further develop the wireless electrochemical approach for the self-assembly of microwires in situ with custom-designed and fabricated 3D cancer spheroids. Unlike traditional electrochemical methods that rely on direct electrical connections to induce currents, our technique utilises bipolar electrodes that operate independently of physical wired connections. These electrodes enable redox reactions through the application of an external electric field. Specifically, feeder electrodes connected to a power supply generate an electric field, while the bipolar electrodes, not physically connected to the feeder electrodes, facilitate the reduction of silver ions from the solution. This process occurs upon applying a voltage across the feeder electrodes, resulting in the formation of self-assembled microwires between the cancer spheroids.Thereby, creating interlinked bioelectronic circuitry with cancer spheroids. We demonstrate that a direct current was needed to stimulate the growth of conductive microwires in the presence of cell spheroids. Microwire growth was successful when using 50 V (0.5 kV/cm) of DC applied to a single spheroid of approximately 800 µm in diameter but could not be achieved with alternating currents. This represents the first proof of the concept of using wireless electrochemistry to grow conductive structures with 3D mammalian cell spheroids.

Enhancement of Shock Wave From Underwater Electrical Wire-Array Explosion at a Fixed Energy by Changing Wire Connection

Enhancement of Shock Wave From Underwater Electrical Wire-Array Explosion at a Fixed Energy by Changing Wire Connection

Wireless driven and self-sensing flexible gripper based on piezoelectric elastomer/high-entropy alloy magnetoelectric composite

The mechanical gripper shows significant importance as an alternative to manual work, but presents certain limitations in its gas or electric power with complex wire connection, presents limited available area and loud working noise, and lacks sensing function for feedback to the environment. In the present work, a novel magnetically driven and self-sensing flexible gripper was prepared based on piezoelectric elastomer and high-entropy alloy composite. The high-entropy alloy is prepared as FeCoNi(AlGa)0.5 to realize high permeability, while the piezoelectric elastomer is synthesized with superior elasticity and low modulus. The incorporation of FeCoNi(AlGa)0.5 into the piezoelectric elastomer exhibits high flexibility, magnetostriction performances and piezoelectric responses, reaching maximum strain of 1534.5 %, maximum magnetostrictive coefficient of 320 ppm and maximum piezoelectric response of 0.28 V/N. Meanwhile, the flexible gripper achieves synchronous wireless driven gripping function with a maximum lifting ratio to dead load over 41.38, and self-sensing function of target physical size with accuracy over 95 %. The flexible gripper shows maximum work power as low as 5 W. Thus, the magnetically driven and self-sensing flexible gripper shows great potential in intelligent industrial equipment.

Developing and Testing a Portable Soil Nutrient Detector in Irrigated and Rainfed Paddy Soils from Java, Indonesia

Data on the soil nutrient content are required to calculate fertilizer rate recommendations. The soil laboratory determines these soil properties, yet the measurement is time-consuming and costly. Meanwhile, portable devices to assess the soil nutrient content in real-time are limited. However, a proprietary and low-cost NPK sensor is available and commonly used in IoT for agriculture. This study aimed to assemble and test a portable, NPK sensor-based device in irrigated and rainfed paddy soils from Java, Indonesia. The device development followed a prototyping approach. The device building included market surveys and opted for an inexpensive, light, and compact soil sensor, power storage, monitor, and wire connectors. Arduino programming language was used to write scripts for data display and sub-device communication. The result is a real-time, portable soil nutrient detector that measures the soil temperature, moisture, pH, electrical conductivity, and N, P, and K contents. Field tests show that the device is sensitive to soil properties and location. The portable soil nutrient detector may be an alternative tool for the real-time measurement of soil nutrients in paddy fields in Indonesia.

Multiple-Split Transmitting Coils for Stable Output Power in Wireless Power Transfer System with Variable Airgaps

In this paper, a tunable multi-split transmitting (TX) coil for a wireless power transfer (WPT) system that accommodates a wide range of distances between the TX and receiving (RX) coils is proposed. This method enables the WPT system to maintain a stable and consistent output power supply to the load, regardless of variations in coupling coefficients caused by changes in the distance between the TX and RX coils. The tunable multi-split TX coil can operate in various modes depending on how the wire connections between each TX coil are configured. This approach adjusts the inductance value of the TX coil for different conditions, using the same amount of coil as a conventional single-loop TX coil. The results show that by adjusting the TX coil to three different modes as the airgap varies from 50 mm to 250 mm, consistent output power is achieved with smaller variations in the input current and voltage compared to those in a conventional system. A conventional system requires an input voltage increase of approximately 529.64%, while the proposed system requires only a 42.93% increase. The proposed system enhances the power transfer capacity of the WPT system, particularly when operating in an over-coupling state. This approach provides a stable output power supply with a standardized and simplified TX coil structure.

Fabrication and characterization of model wireless biosensor-based electrochemical impedance spectroscopy (EIS) for detecting HER2 in plasma as therapeutics

PurposeEarly prediction of any type of cancer is important for the treatment of this type of disease, therefore, our target to evaluate whether monitoring early changes in plasma human epidermal growth factor receptor 2 (HER2) levels (using EIS), could help in the treatment of breast cancer or not? Human epidermal growth factor receptor 2 (HER2) overexpression is an important biomarker for treatment selection in earlier stages of cancers. The combined detection of the HER2 gene in plasma for blood cancer provides an important reference index for the prognosis of metastasis to other tissues. For this purpose, the authors fabricated and characterized a model wireless biosensor-based electrochemical impedance spectroscopy (EIS) for detecting HER2 plasma as therapeutics.Design/methodology/approachMost sensors generally are fabricated based on a connection between component of the sensors and the external circuits through wires. Although these types of sensors provide suitable sensitivities and also quick responses, the connection wires can be limited to the sensing ability in various devices approximately. Therefore, the authors designed a wireless sensor, which can provide the advantages of in vivo sensing and also long-distance sensing, quickly.FindingsThe biosensor structure was designed for detection of HER2, HER3 and HER-4 from lab-on-chip approach with six units of screen-printed electrode (SPE), which is built of an electrochemical device of gold/silver, silver/silver or carbon electrodes. The results exhibited that the biosensor is completely selective at low concentrations of the plasma and HER2 detection via the standard addition approach has a linearity plot, therefore, by using this type of biosensors HER2 in plasma can be detected.Originality/valueThis is then followed by detecting HER2 in real plasma using standard way which proved to have great linearity (R2 = 0.991) proving that this technique can be used to detect HER2 solution in real patients.

불완전 접촉으로 인한 아산화동 증식 발열 형상의 X-선 회절 분석 및 판별법에 대한 연구

불완전 접촉으로 인한 아산화동 증식 발열 형상의 X-선 회절 분석 및 판별법에 대한 연구

Real-time biological early-warning system based on freshwater mussels’ valvometry data

Abstract. Quantifying the effects of external climatic and anthropogenic stressors on aquatic ecosystems is an important task for scientific purposes and management progress in the field of water resources. In this study, we propose an innovative use of biotic communities as real-time indicators, which offers a promising solution to directly quantify the impact of these external stressors on the aquatic ecosystem health. Specifically, we investigated the influence of natural river floods on riverine biotic communities using freshwater mussels (FMs) as reliable biosensors. Using the valvometry technique, we monitored the valve gaping of FMs and analysed both the amplitude and frequency. The valve movement of the FMs was tracked by installing a magnet on one valve and a Hall effect sensor on the other valve. The magnetic field between the magnet and the sensor was recorded using an Arduino board, and its changes over time were normalised to give the opening percentage of the FMs (how open the mussels were). The recorded data were then analysed using continuous wavelet transform (CWT) analysis to study the time-dependent frequency of the signals. The experiments were carried out both in a laboratory flume and in the Paglia River (Italy). The laboratory experiments were conducted with FMs in two configurations: freely moving on the bed and immobilised on vertical rods. Testing of the immobilised configuration was necessary because the same configuration was used in the field in order to prevent FMs from packing against the downstream wall of the protection cage during floods or from breaking their connection wires. These experiments allowed us to verify that immobilised mussels show similar responses to abrupt changes in flow conditions as free mussels. Moreover, immobilised mussels produced more neat and interpretable signals than free-moving mussels due to the reduced number of features resulting from movement constraints. We then analysed the response of 13 immobilised mussels under real river conditions during a flood on 31 March 2022. The FMs in the field showed a rapid and significant change in valve gap frequency as the flood escalated, confirming the general behaviour observed in the laboratory in the presence of an abrupt increase in the flow. These results highlight the effectiveness of using FMs as biosensors for the timely detection of environmental stressors related to natural floods and emphasise the utility of CWT as a powerful signal-processing tool for the analysis of valvometry data. The study proposes the integration of FM valvometry and CWT for the development of operational real-time biological early-warning systems (BEWSs) with the aim of monitoring and protecting aquatic ecosystems. Future research should focus on extending the investigation of the responsiveness of FMs to specific stressors (e.g. turbidity, temperature, and chemicals) and on testing the applications of the proposed BEWSs to quantify the impact of both natural stressors (e.g. heat waves and droughts) and anthropogenic stressors (e.g. hydropeaking, reservoir flushing, and chemical contamination).

Intermittent fault diagnosis in connector components based on arc wave characteristics

Intermittent faults are widely present in aviation electronic devices, especially in various electrical connectors. It is usually hard to diagnose the source of the intermittent faults, which brings a huge challenge to the repair and maintenance of equipment. This paper focuses on the intermittent faults in typical aviation electrical connectors activated by shock test. The transient arc wave is observed on a nanosecond scale during the occurrence of the intermittent faults. An arc signal model is constructed to analyze the impact factors of the signal. Based on the arc wave characteristics, further intermittent fault diagnostic analyses are conducted on four types of connector components: damaged solder joints, cracked pin connections, loose wire connections and worn electrical connectors. The effective arc wave components of the raw signals are extracted using Variational Mode Decomposition (VMD), and a comparison is made between traditional diagnostic method and CNN-based deep learning method. The results show that the combination of VMD-CNN-SVM achieves the optimal diagnostic effect. The diagnostic results reflect that the proposed arc signal features are suitable for diagnosing intermittent faults in connector components.

Improvement of Power Factor in Wireless Electric Vehicle Charging Using Inductive Power Transfer Topology

The EV requires energy supplied to its motors to function properly. This required energy either can be transmitted by a physical wired connection or by wireless power transfer firstly to the battery using charging of the EV system and then battery discharges to supply to the vehicle. This paper deals with the wireless transfer of power using the induction method for charging battery of the vehicle using electric energy for its functioning as it is the most suitable and fast mode to charge the batteries of many vehicles altogether at charging station. The challenges recently faced by EV’s includes the movement of energy from the energy supply point to the destination i.e., EV’s without the direct interaction of battery and energy source. Many topologies have been introduced in this regard and several simulation models are built.