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This paper introduces a primary pad for wireless charging applications, which is able to transfer high power over large air gaps and is tolerant to lateral displacements suitable for electric vehicle charging applications. The developed pad is an improved solenoid designed specifically to address issues such as flux leakage and loss while retaining good coupling. It is a hybrid structure that consists of a combination of rectangular- or square-shaped coils and a central solenoid, all connected in series. When energized, it produces a single-sided, polarized flux similar to the flux pattern of the solenoid and double D (DDP) pads. The power transfer capability of this pad is investigated through finite-element analysis simulations. The results are compared first to a similar sized solenoid from which it was derived, and also a DDP primary pad and are verified through measurements on prototype systems in the laboratory. The aim of this paper is to provide an improved hybrid solenoid pad showing higher coupling factors and lower stray field emissions with a performance (coupling and stray field emissions) similar to that of DDPs.

The convenience of mobile and biometric payments are making these systems increasingly popular in the Korean offline payments market. However, the diffusion of alternative offline payment systems such as mobile or biometric payments is slower than expected. Therefore, the purpose of this study is to analyze consumer preferences for payment systems and examine the effects of consumers’ characteristics on the marginal utility of mobile and biometric payments. It uses the discrete choice experiment consisting of five major attributes to estimate preference parameters, and analyzes the data using the mixed logit model. The results show that consumers preferred cards to mobile and biometric payments even if they displayed the same level of related attributes. The scenario analysis results based on consumer preferences also showed the need to develop the overall attribute level of mobile and biometric payments. Furthermore, consumers’ positive attitude or innovativeness toward hi-tech products has a significantly positive effect on preferences for alternative payments. Based on the results, this study provides theoretical implications for consumer preference studies on payment systems and proposes market strategies for the diffusion of major next-generation payment systems from multiple aspects.

A dynamic inductive power transfer (IPT) system is a safe and convenient solution to address the issues related to the limited battery capacity and travel distance of electric vehicles (EVs). In recent years, practical aspects of dynamic IPT systems have been investigated to advance various IPT technologies from laboratories to roadways. This paper suggests a configuration to mitigate some of the installation and maintenance concerns of IPT roadways by proposing a switchable inductively coupled connector. Besides providing galvanic isolation, the inductively coupled connector helps maintain a constant and load-independent current in the primary coupler. Moreover, each primary coupler is connected to a common H-bridge through a single DC switch minimizing the number of components required to energize each coupler independently. A mathematical analysis and simulation results have been provided to validate a scaled 3.3kW prototype IPT system employing the proposed configuration.

Inductive power transfer (IPT) is a promising method for electric vehicle (EV) charging that is safe and practical. The critical aspects of IPT systems to achieve roadway charging are robustness, reliability, low cost and high power transfer. This paper presents two variations of a primary IPT double-D (DD) coupler that reduce ferrite volume, stray-fields and cost while having increased power rating at the expense of magnetic coupling and higher primary pad currents. A two-step ferrite shaping method is used for optimisation while keeping the primary coil and secondary pad unchanged. The ferrite volume is limited to the high flux density locations in a first step to reduce ferrite volume by 70%. Following this, an additional 14% ferrite volume is added to shape and reduce the stray fields by 23%.

Advances in machine learning (ML) have ignited hardware innovations for efficient execution of the ML models many of which are memory-bound (e.g., long short-term memories, multi-level perceptrons, and recurrent neural networks). Specifically, inference using these ML models with small batches, as would be the case at the Cloud edge, has little reuse of the large filters and is deeply memory-bound. Simultaneously, processing-in or -near memory (PIM or PNM) is promising unprecedented high-bandwidth connection between compute and memory. Fortunately, the memory-bound ML models are a good fit for PIM. We focus on digital PIM which provides higher bandwidth than PNM and does not incur the reliability issues of analog PIM. Previous PIM and PNM approaches advocate full processor cores which do not conform to PIM’s severe area and power constraints. We describe Newton, a major DRAM maker’s upcoming accelerator-in-memory (AiM) product for machine learning, which makes the following contributions: (1) To satisfy PIM’s area constraints, Newton (a) places a minimal compute of only multiply-accumulate units and buffers in the DRAM which avoids the full-core area and power overheads of previous work and thus makes PIM feasible for the first time, and (b) employs a DRAM-like interface for the host to issue commands to the PIM compute. The PIM compute is rate-matched to the internal DRAM bandwidth and employs a non-intuitive, global input vector buffer shared by the entire channel to capture input reuse while amortizing buffer area cost. To the host, Newton’s interface is indistinguishable from regular DRAM without any offloading overheads and PIM/non-PIM mode switching, and with the same deterministic latencies even for floating-point commands. (2) To prevent the PIM-host interface from becoming a bottleneck, we include three optimizations: commands which gang multiple compute operations both within a bank and across banks; complex, multi-step compute commands – both of which save critical command bandwidth; and targeted reduction of t FAW overhead. (3) To capture output vector reuse with reasonable buffering, Newton employs an unusually-wide interleaved layout for the matrix. Our simulations running state-of-the-art neural networks show that building on a realistic HBM2E-like DRAM, Newton achieves 10x and 54x average speedup over a non-PIM system with infinite compute that perfectly uses the external DRAM bandwidth and a realistic GPU, respectively.

Demand for high throughput manufacturing has recently increased in various fields, such as electronics, photonics, optical devices, and energy. Moreover, flexible electronic devices are indispensable in applications such as touch screens, transparent conductive electrodes, transparent film heaters, organic photovoltaics, organic light-emitting diodes, and battery. For these applications, a large-area roll-to-roll (R2R) process is a promising method for producing with high throughput. However, bending deformation of rollers is unavoidable in a large-scale R2R system, which produces non-uniformity in force distribution during processing and reduces the sample quality. In this study, we propose a new R2R imprinting module to mitigate the deformation by using an additional backup roller to achieve uniform force distribution. From numerical simulations, we found that there exists an optimal imprinting force for each backup roller length to obtain the best uniformity. Experimental results using a large-area pressure sensor verified the effectiveness of the proposed method. Finally, the R2R nanoimprint lithography process showed that the proposed method produces patterns of 100 nm width with uniform residual layer thickness, which are distributed across the substrate of 1.2 m width.

Platform service providers in Korea and worldwide have launched over-the-top (OTT) bundled services, which increase market competitiveness. Forecasting the market expansion strategies of these providers can thus shed light on their future actions and influence government policies. In this context, this is the first study to analyze consumer preferences for bundled pay-TV and OTT services. However, due to a lack of market data availability, we conducted a discrete choice experiment and analyzed the marginal utilities of attributes using a mixed logit model. The results demonstrate that consumers expect an additional discount for pay-TV services when bundled with OTT services and that the more bundled services they currently use, the less sensitive they are to the discount rate. Furthermore, we found that OTT and TV broadcasting services have a complementary, rather than a substitute, relationship. Finally, according to a simulation analysis for the Korean broadcasting market, bundling OTT services to expand the market share of pay-TV service providers was largely ineffective.

A recently proposed magnetic structure called Tripolar Pad (TPP) is investigated as a primary pad in an inductive power transfer battery charging system for electric vehicles. In this paper, a TPP primary is evaluated for 3.3 kW power transfer to both a circular pad and a bipolar pad as secondary pads. A mathematical model is presented to describe the power transfer from the TPP primary to the secondary pads then a control scheme is proposed which exploits the mutual decoupling between the TPP coils to find optimal primary currents. The optimization of the primary currents in the TPP improved the effective coupling factor over traditional topologies, particularly when the secondary was misaligned, and maintained leakage magnetic flux below International Commission on Non-Ionizing Radiation Protection guidelines. The result for the proposed TPP is validated with practical measurements.

Inductive power transfer (IPT) systems have been researched as one of the methods for wireless electric vehicle charging. One aspect often overlooked in IPT systems is the rise of temperature in the pads during operation in applications where active cooling is difficult, such as in a buried structure within a roadway. This paper conducts a thermal analysis of a buried double-D (DD) primary pad in simulations and experimentally validates the findings.

Inductive Power Transfer (IPT) is a method of transferring power without physical contact between two coils. SAEJ2954 is a newly defined standard which specifies several requirements for single coil structures to be used in EV charging. The Tripolar pad (TPP) is a multi-coil design which has shown to offer various advantages over single coil designs. Conventional operation methods require twelve switches. This paper explores the use of an eight-switch circuit topology in a wye configuration for interoperability of the TPP with SAEJ2954 pads at a power level of WPT2 and height of Z2.

The VisionCube is a 2-unit CubeSat developed in house, of which the primary mission is detecting the occurrence of transient luminous events (TLEs) in the upper atmosphere and obtaining corresponding images from a low Earth orbit. An onboard TLE observation system of the VisionCube CubeSat is designed and developed by incorporating a photon-sensitive multi-anode photon-multiplier tube (MaPMT) and an image sensor. Also, a distinctive TLE observation software which enables detection of the TLEs and capture of images in a timely manner is devised. By taking into account the limited resources of a small CubeSat in size and power, the onboard observation system is developed employing a system-on-chip device by which both hardware and software can be integrated seamlessly. The purpose of this study is to investigate the functionality of the hardware and the validity of the software algorithm to show that the onboard system will function properly with no human intervention during the operations in space. To this end, a ground simulation facility is constructed to emulate TLEs occurring in space using a set of ultraviolet light-emitting diodes (UV LEDs) inside a darkbox. Based on the analysis of the spectral and temporal properties of the TLEs, the randomly generated UV LED pulses are chosen for verification scenarios for the TLE observation system. The validation results show that the hardware and the software algorithm of the onboard observation systems can effectively detect the TLEs and obtain the images during the in-orbit operation.

Inductive Power Transfer (IPT) systems have been proposed as a promising solution for charging electric vehicles (EVs). The design of magnetic structures is an important aspect of IPT systems to maximise power transfer capability and minimise leakage magnetic field. This paper investigates a recently proposed Tripolar Pad (TPP), to show how different coil and ferrite shapes impact the power transfer capability and leakage magnetic field of this particular IPT system in comparison to a conventional circular/square pad (CP). The simulation findings are validated using a prototype TPP and CP in the laboratory.

Inductive Power Transfer (IPT) systems have been proposed for various applications and have been increasingly gaining interest for electric vehicle (EV) charging. Numerous magnetic structures have been proposed for IPT systems for EV charging including structures involving mutually decoupled coils. This paper presents an analytical model of an IPT system composed of a two coil primary pad and a single coil secondary pad to show the importance of mutually decoupled coils in IPT systems using multi-coil primary pads. A controller is also proposed to find the optimal primary currents needed to achieve the “best” effective coupling factors at any secondary displacement for mutually decoupled primary coils. A 1.5 kW prototype system is implemented in the laboratory to validate the findings for ideally aligned and misaligned cases.

Inductive Power Transfer (TPT) systems have been proposed in recent years as a safe, convenient and robust method of battery charging in EVs and robots. In an IPT system, the magnetic design of the primary and secondary pads is an important factor that determines the power transfer capability. This paper proposes the Tripolar Pad (TPP), a novel three coil magnetic pad utilising mutually decoupled coils. The TPP maintains tolerance to rotational displacements similar to nonpolarised pads, but uses polarised fields to improve power transfer. Simulation results are first shown in the paper and then validated by a scaled prototype.

This paper reviews the development of a new contactless power transfer technique termed as CCPT (Capacitively Coupled Power Transfer). The basic working principle and possible coupling structures of CCPT are investigated and discussed. A CCPT system is featured for its ability to transfer power through metal barriers, low standing power loss, low EMI, as well as the simplicity in circuit topologies. Opportunities and challenges such as high frequency circuits and parasitic phenomenon in CCPT are discussed and possible applications of this technique are also presented.

A software architecture style for OCR to increase portability is presented. A hybrid style of four layers, combined with a pipe & filter and layer-type architecture is adopted to reduce the platform dependency keeping the cascading process stream of general OCR. The OCR process constructs a top layer to accomplish the main task. Data manager is separated as a different layer from the top layer, which handles input and knowledge data of the classifier. To provide a unified API, an interface layer is included. A neural network based general OCR source code is totally re-written on the foundation of the proposed style. As a result, confirmed a high portability rate over 99% of source code reuse without modification and performance sacrifices is achieved in the experiment.

A pair of three‐way transmission‐line speaker systems was designed, constructed, and tested for the purpose of providing a high‐accuracy reference monitor capable of reproducing the full audio range with extremely low harmonic distortion and fast transient response with minimal coloration. Each of the speaker cabinets is a mirror image of the other; and edges are made rounded to minimize diffraction effects. The use of six mid‐range drivers enclosed separately from the woofer in each of the extremely stiff cabinets ensure linear operation even at fairly high levels of power input. The tweeters, also enclosed separately, are arranged to provide wide dispersion. While a three‐way crossover network is incorporated, separate input jacks allow for bypass in order to accommodate tri‐amplified inputs. The transmission line provides a perfectly resistive termination to the woofers, functions as a low‐pass filter and virtually eliminates cabinet resonance. Damping material varies in density, tapering off from 0.5 lb/ ft3, where the last 30 cm of the transmission line is unfilled. Directivity through 180° proved be extremely even in the test ranges of 101 to 13 212 Hz.