Commercial Electronic Devices Research Articles

Studying ReRAM devices at Low Earth Orbits using the LabOSat platform

LabOSat (acronym for “Laboratory On a Satellite”) is a type of electronic platform designed to perform experiments in harsh, remote environments. Up to now, LabOSat platforms have been used mainly for characterizing and validating custom and commercial electronic devices at Low Earth Orbits (LEO). Many of these platforms are running experiments aboard ÑuSat satellites, which are built and operated by Argentine company Satellogic. A brief description of LabOSat platforms is presented here, along with details of their validation both at LEO and at a nuclear reactor. The electrical characterization of custom non-volatile memory cells — as performed by a LabOSat platform at LEO — is also described, and the results of such experiment are compared with results obtained on Earth. The memory cells studied were TiO2-based and La1/3Ca2/3MnO3-based ReRAM devices.

Securing SPI (Serial Peripheral Interface) Data for Field Replaceable Units (FRUs) in Commercial Electronic Devices

Securing SPI (Serial Peripheral Interface) Data for Field Replaceable Units (FRUs) in Commercial Electronic Devices

(Invited) Two-Dimensional Materials for Wearable Electronics

The term “smart-clothes” has been applied over the past few years referring to the attachment of commercial (rigid) electronic devices to an article of clothing with applications mostly in performance sports or futuristic fashion shows. An actual smart fabric comprising the seamless integration of soft (flexible) electronics within the textile itself is still mainly in the R&D stages at prohibitively high manufacturing costs. Two-dimensional materials, such as graphene and Mxene, have demonstrated attractive electrical and electrochemical properties for flexible electronic applications. However, their direct incorporation into textile structures for truly "wearable" applications have rarely been investigated or demonstrated. In this talk, we will introduce the recent progress of our research group on relevant topics, namely 1) 2D-material based hybrid yarns as supercapacitors via industrialized wet-spinning processes, and 2) wearable microsupercapacitors on various textile structures (PET or Cotton fabrics, and PP or nylon nonwovens) with good washfastness and high flexibility. We will focus on the fundamental aspects and major technological obstacles of the integration of novel functional materials with traditional textile processings and products.

A Dimensionally Aligned Signal Projection for Classification of Unintended Radiated Emissions

Characterization of unintended radiated emissions (URE) from electronic devices plays an important role in many research areas from electromagnetic interference to nonintrusive load monitoring to information system security. URE can provide insights for applications ranging from load disaggregation and energy efficiency to condition-based maintenance of equipment-based upon detected fault conditions. URE characterization often requires subject matter expertise to tailor transforms and feature extractors for the specific electrical devices of interest. We present a novel approach, named dimensionally aligned signal projection (DASP), for projecting aligned signal characteristics that are inherent to the physical implementation of many commercial electronic devices. These projections minimize the need for an intimate understanding of the underlying physical circuitry and significantly reduce the number of features required for signal classification. We present three possible DASP algorithms that leverage frequency harmonics, modulation alignments, and frequency peak spacings, along with a two-dimensional image manipulation method for statistical feature extraction. To demonstrate the ability of DASP to generate relevant features from URE, we measured the conducted URE from 14 residential electronic devices using a 2 MS/s collection system. A linear discriminant analysis classifier was trained using DASP generated features and was blind tested resulting in a greater than 90% classification accuracy for each of the DASP algorithms and an accuracy of 99.1% when DASP features are used in combination. Furthermore, we show that a rank reduced feature set of the combined DASP algorithms provides a 98.9% classification accuracy with only three features and outperforms a set of spectral features in terms of general classification as well as applicability across a broad number of devices.

Validation of Electronic Activity Monitor Devices During Treadmill Walking.

The purpose of this study was to assess the validity of the step count measurement of commercial electronic activity monitor devices. Two popular models, Fitbit Charge HR and Mi Band 2, were selected for treadmill walking in a single session. Thirty healthy volunteers walked at five predetermined speeds (0.90, 1.12, 1.33, 1.54, and 1.78 m/s) on a treadmill with both Fitbit Charge HR and Mi Band 2 worn on their dominant hand's wrist. Observers counted the steps, with the aid of taped video, which was taken as the criterion measure for steps. The validity of the electronic activity devices was assessed by (1) Paired sample t test with the criterion measures and (2) Pearson's correlation coefficients and the corresponding p-values were calculated to compare the output of devices with manual step count. In addition, Bland-Altman plots were constructed to visually inspect the data and to assess agreement with the criterion measures. There were no significant differences in step measurement between Fitbit Charge HR and Mi Band 2 with the criterion measures. Besides, there was a very strong agreement between step count measurements obtained using the Fitbit Charge HR (r = 0.99) and the Mi Band 2 (r = 0.99), at five predetermined speeds while comparing with the observed step counts. Both Fitbit Charge HR and Mi Band 2 provided accurate step count measurement in the treadmill walking test.

Competition Scenario of Taiwan Transformer Industry

A major applicant of transformers was to increase voltage before transmitting electrical energy over long distances through wires. Most of consumer and commercial electronics for daily using like personal computers, home theaters, air conditions, TVs, cell phones and notebooks, etc., needed transformers to do electrical transfer. Moreover, in order to adopt the design of consumer and commercial electronic devices, the specifications of transformers including the circuits, diameter of wires, turns of windings, and size of cores and bobbins were different; transformers were customization. There were standard specifications for transformers. The common types of transformers were EI type and toroidal type, etc. Due to the internationalization and concentration of business, economic executives no longer had a strong connection with their place of production. Production locations could transfer or collapse for various reasons, amongst them changing cost factors or competition.

市販の音響電子機器を用いた水中音響通信用チャネルサウンダとそのフィールド評価結果

市販の音響電子機器を用いた水中音響通信用チャネルサウンダとそのフィールド評価結果

On the Implementation of the IEC 61850 Standard: Will Different Manufacturer Devices Behave Similarly under Identical Conditions?

Standardization in smart grid communications is necessary to facilitate complex operations of modern power system functions. However, the strong coupling between the cyber and physical domains of the contemporary grid exposes the system to vulnerabilities and thus places more burden on standards’ developers. As such, standards need to be continuously assessed for reliability and are expected to be implemented properly on field devices. However, the actual implementation of common standards varies between vendors, which may lead to different behaviors of the devices even if present under similar conditions. The work in this paper tested the implementation of the International Electro-technical Commission’s Generic Object Oriented Substation Event GOOSE (IEC 61850 GOOSE) messaging protocol on commercial Intelligent Electronic Devices (IEDs) and the open source libiec61850 library—also used in commercial devices—which showed different behaviors in identical situations. Based on the test results and analysis of some features of the IEC 61850 GOOSE protocol itself, this paper proposes guidelines and recommendations for proper implementation of the standard functionalities.

Electromagnetic Interference Shielding Effectiveness of Silver Thin Films Fabricated By Dry Plasma Reduction

Owing to the wide use of commercial, military, and scientific electronic devices and communication instruments, electromagnetic interference (EMI) shielding of radio frequency radiation is becoming a serious global problem. In general, light weight, high conductivity and excellent adhesion are required for EMI shielding materials. Metals and their composites are the most popular materials for EMI shielding effectiveness. Currently, they are usually deposited by sputtering and electrodeposition. However, there are some inconvenience for their wide application such as expensive vacuum equipment, or high voltage and small cell used for deposition method. Recently, we developed a new process for efficiently synthesizing supported metal, core-shell, bimetallic nanoparticles by using dry plasma reduction (DPR) near room temperature under atmospheric pressure. The aim of this technique was to overcome the previous mentioned process restrictions. We present, for the first time, here the use of DPR to fabricate silver thin film on PET substrate under atmospheric pressure, without using any toxic chemicals, near room temperature for EMI shielding applications. The morphology and silver film thickness are characterized through HRSEM. The formation of silver nanoparticles are examined using TEM, XRD and XPS measurements. Silver film conductivities are measured by four point probe. The results show that silver thin films are successfully fabricated by DPR. EMI shielding effectiveness is measured in the frequency range from 0.045 to 1 GHz. As the results, the silver thin films have significant shielding effectiveness of more than 55 dB at 0.1 GHz with near 600 nm thickness and sheet resistance of 0.087 Ω/□. Furthermore, the increase in silver film thickness resulted in decreasing sheet resistance and increasing EMI shielding effectiveness.

Nanostructured Carbon Materials for Li-S and Li-Se Batteries

Novel energy storage systems with high energy density and reduced cost has drawn significant attention due to the emerging storage application, such as commercial electronic devices, electrical vehicles, and grid storage systems. Conventional Li-ion batteries, however, are hard to meet the requirement for those applications in near future due to the theoretical energy density limit. Therefore, advanced batteries with different chemistry which could provide higher capacity and energy density are necessary for further development. Among many candidates, Lithium-sulfur battery (Li-S) has been recognized as one promising system due to its high gravimetric energy density and low material cost, which is superior to most of current Li-ion batteries. Besides sulfur, selenium (Se) has also been involved in the battery study, since it shares similar lithiation/delithiation mechanism to sulfur. In addition, although with lower gravimetric capacity than sulfur, the better electrical conductivity and less shuttling behavior make selenium parallel path of the sulfur system. Due to their dissolution nature of both Li-S and Li-Se systems, supporting materials which provide a robust framework with sufficient internal space and reactive sites, are critical for the chemistry. Although there were many candidates for the supporting material in Li-S and Li-Se batteries, such as metal oxides and graphene based materials, porous carbon materials are still dominant for a practical point of view. Relatively low cost, Industrial scale production and convenient handling make porous carbon materials superior to other supporting materials. Here we present a summary of our work on several porous carbon materials as the supporting material, which help enable high S/Se loading on both material level and electrode level, for the Li-S and Li-Se batteries. We will demonstrate the preparation, characterization and electrochemical performance of the carbon materials. The comparison of corresponding Li-S and Li-Se will be also described. Besides carbon materials, we will also discuss about our study on the influence of polymer binder and electrolyte on the optimized electrodes on both Li-S and Li-Se systems. Further discussions on the battery design and cell-level energy density estimation will be also addressed.

The dawning of the diamond age

A well-dressed gentleman sits in the lobby of an upscale hotel in Washington, D.C., holding a black box full of diamonds. The man, Adam Khan, isn’t a jewel thief, but he is trying to sell diamonds. Well, lab-grown diamond films to be accurate. Khan is the founder and chief executive officer of Akhan Semiconductor, and he’s trying to usher in the age of diamond electronics. Khan and like-minded researchers think diamond and its exceptional properties could replace current electronic stalwarts such as silicon and outperform other advanced materials in high-powered applications. This optimism has been sparked by the ability to grow larger, higher-quality diamond films than ever before. Yet many experts also see several technical hurdles to overcome before commercial electronic devices will capitalize on diamond’s extreme properties. And some people believe these hurdles could take many years to clear. Khan is not among those people. Akhan launched about three

Microprocessor-Based Athlete Health Monitoring Device based on Heart Rate and Stride Length Calculation

Abnormal heart rate or low heart rate during exercise or recovery has been known to cause cardiac arrest and even sudden death in some cases. Similarly, research has shown that low step rate while running may be the causal factor for running injuries due to the force impact exerted and the extra loadings on the lower body joints. Commercial electronic devices used by athletes typically use either accelerometers or coil springs to estimate the step rate resulting in low accuracy. This paper describes the design a low-cost, wearable device that can help athletes monitor their physical activity while running or walking and report step rate, heart rate, distance covered, time elapsed and calories burnt with high accuracy. The system calculates the step rate by analyzing the signal generated from two Force Sensitive Resistors (FSRs) inserted above the insole of a running shoe which is connected to a microcontroller strapped to the athlete’s ankle. According to the experimental results, the prototype was found to have an average accuracy of 97% in measuring the distance covered.

Enhancing the bioremediation by harvesting electricity from the heavily contaminated sediments

To test the long-term applicability of scaled-up sediment microbial fuel cells (SMFCs) in simultaneous bioremediation of toxic-contaminated sediments and power-supply for electronic devices, a 100L SMFC inoculate with heavily contaminated sediments has been assembled and operated for over 2years without external electron donor addition. The total organic chemical (TOC) degradation efficiency was 22.1% in the electricity generating SMFCs, which is significantly higher than that in the open-circuited SMFC (3.8%). The organic matters including contaminants in the contaminated sediments were sufficient for the electricity generation of SMFCs, even up to 8.5years by the present SMFC theoretically. By using a power management system (PMS), the SMFC electricity could be harvested into batteries and used by commercial electronic devices. The results indicated that the SMFC–PMS system could be applied as a long-term and effective tool to simultaneously stimulate the bioremediation of the contaminated sediments and supply power for commercial devices.

Electromagnetic interference shielding properties of nanocomposites for commercial electronic devices

A novel functional nanocomposites microwave shielding material using natural rubber (NR) loaded with binary active fillers barium hexaferrite (BF) (BaFe12O19) and carbon nanoparticle (CB) were fabricated by conventional roll milling technique. Nanocrystalline barium hexaferrite with particle size of 16 nm were successfully synthesized by hydrothermal approach at low temperature. The surface morphology of the nanocomposites was investigated using X-ray, field emission scanning electron microscopy and transmission electron microscopy. The electrical resistivity of the nanocomposites is decreased with BF loading level. The dielectric constant of the composites is decreased with increasing microwave frequency. NR/BF nanocomposites were screened for electromagnetic interference (EMI) shielding effectiveness (SE) over a frequency band of 1---12 GHz. A maximum SE value is approximately 75 dB in the frequency range of 1---12 GHz for BF content of 20 wt % and thickness of 1 mm. An excellent agreement between the theoretically predicted SE and the measured data was found. These features collectively demonstrated the potential of NR/BF nanocomposites for versatile applications in microwave shielding application and commercial electronic devices issues.

Effect of crosslinking reaction on the electromagnetic interference shielding of a Fe–Si–Al alloy (Sendust)/polymer composite at high frequency

In recent years, development of advanced electronic devices and communication instruments has led to increased demand for electromagnetic interference (EMI) shielding because high‐frequency microwave generates undesired noise which can affect the proper operation of commercial, military and scientific electronic devices as well as the health of our human body. In this study, we investigated the effect of crosslinking reaction of polymer matrix on the EMI shielding performance of a Fe–Si–Al alloy (Sendust)/polymer (poly(styrene‐b‐ethylenebutadiene‐b‐styrene)) composite. The crosslinking reaction of polymer matrix enhanced the melt viscosity of the polymer blend which helped the alignment of the metal flake into rolling direction to induce enhanced anisotropy of the composite. The complex permeability of the flake composite was substantially increased, and the reflection loss at 0.8 GHz was −9.3 dB. The absorption efficiency of the crosslinked polymer/flake composite was dramatically increased around 1 GHz compared to the crosslinked/bulk powder composite. Normalized power loss reached almost 1 in Giga Hertz frequency. The Sendust/polymer composites are practically useful for the EMI shielding purpose. Copyright © 2014 John Wiley & Sons, Ltd.

Graphene based composite for electromagnetic interference shielding

Because of the wide use of commercial, military, and scientific electronic devices and communication instruments, electromagnetic interference (EMI) shielding of radio frequency radiation continues to be a serious concern for modern society. The preparation of EMI shielding materials has obtained an increased attention in the academic and industrial field. Compared to the conventional metal-based EMI materials, polymer conposites containing carbon-based nanofillers have their own advantages, such as being lightweight, resistance to corrosion, excellent processability, and broad absorption bandwith and flexible. Graphene, a new class of 2D carbon nanomaterials, possesses extraordinary electrical, mechanical, and thermal properties. These unique features offer great promise for its use in EMI shielding. Besides, for the application in special fields such as aerospace, weapon equipment, military protection, vehicles and microelectronics where the materials with superior thermal stability, excellent mechanical properties, perfect radiation, and electrical resistant performance are required, high performance graphene composites could be a better candidate to fulfill the task. In this review, EMI shielding graphene based composite were classified by the method of graphene preparation.

Development of an Indoor Airflow Energy Harvesting System for Building Environment Monitoring

Wireless sensor networks (WSNs) have been widely used for intelligent building management applications. Typically, indoor environment parameters such as illumination, temperature, humidity and air quality are monitored and adjusted by an intelligent building management system. However, owing to the short life-span of the batteries used at the sensor nodes, the maintenance of such systems has been labor-intensive and time-consuming. This paper discusses a battery-less self-powering system that converts the mechanical energy from the airflow in ventilation ducts into electrical energy. The system uses a flutter energy conversion device (FECD) capable of working at low airflow speeds while installed on the ventilation ducts inside of buildings. A power management strategy implemented with a circuit system ensures sufficient power for driving commercial electronic devices. For instance, the power management circuit is capable of charging a 1 F super capacitor to 2 V under ventilation duct airflow speeds of less than 3 m/s.

Contact resistance properties of electron-beam-cured anisotropic conductive films

An anisotropic conductive film (ACF) is a thin adhesive epoxy layer that is widely used to connect circuits in highly-integrated electronic devices. To bind two electric circuits, an ACF is pasted between the circuits and pressed with an optimum pressure so that the joints can be electronically connected. For the curing of the resin, electron-beam (E-beam) irradiation is known to be an environmentally friendly technique and exhibits many technical advantages over conventional thermal curing in terms of low temperature and reduced curing time. In this method, the applied pressure and electron-beam dose are critical parameters to maximize the conductivity without a failing of the connection between the circuits. For the minimization of the contact resistance after curing by using E-beam irradiation, curable epoxy resin was mixed with conductive particles made of Ni/Au-plated polymer spheres with a mean particle size of 10 µm in a ratio of 5: 1 by weight. The mixed resin was pasted on rigid boards having circuits of 100-µm pitch and was irradiated by using an E-beam. The optimum dose for E-beam irradiation for a reasonable curing, the contact resistance values, and the reliability of the cured film were systematically investigated as functions of E-beam dose, applied pressure and temperature. The lowest contact resistance values were obtained when the specimens were irradiated by an 80-kGy E-beam under a constant pressure of 5 kgf/cm2. At this condition, the minimum contact resistance was 80 ± 0.015 mΩ, which is significantly lower than the values obtained from commercial products, and the values were maintained within a 5% increase when the samples were kept at 100 °C for 294 hours. Our results demonstrate that an E-beam irradiation technique can be applied for curing ACFs for commercial electronic devices.

Parallelized sub-resource loading for web rendering engine

High-performance web browsers would be more emphasized in the commercial electronic devices including smart phones, tablet PCs, netbooks, laptops, and smart TVs. On the other hand, the web browsers still experience performance degradation due to the increase of resources provided on a web page. In fact, web pages with a large number of images require a very complex rendering operations. In this paper, we propose a parallel web browser for rapid web rendering operations with exploiting thread-level parallelism. The proposed architecture parallelizes the sub-resource loading operation on various platforms including the conventional PC system and the mobile embedded system. The proposed parallel sub-resource loading operation achieves a maximum speedup of 1.87 in a quad-core system. For the dual-core embedded system, a maximum speed-up is as large as 1.45.

Emergency response to the nuclear accident at the Fukushima Daiichi Nuclear Power Plants using mobile rescue robots

On March 11, 2011, a massive earthquake (magnitude 9.0) and accompanying tsunami hit the Tohoku region of eastern Japan. Since then, the Fukushima Daiichi Nuclear Power Plants have been facing a crisis due to the loss of all power that resulted from the meltdown accidents. Three buildings housing nuclear reactors were seriously damaged from hydrogen explosions, and, in one building, the nuclear reactions became out of control. It was too dangerous for humans to enter the buildings to inspect the damage because radioactive materials were also being released. In response to this crisis, it was decided that mobile rescue robots would be used to carry out surveillance missions. The mobile rescue robots needed could not be delivered to the Tokyo Electric Power Company (TEPCO) until various technical issues were resolved. Those issues involved hardware reliability, communication functions, and the ability of the robots' electronic components to withstand radiation. Additional sensors and functionality that would enable the robots to respond effectively to the crisis were also needed. Available robots were therefore retrofitted for the disaster reponse missions. First, the radiation tolerance of the electronic componenets was checked by means of gamma ray irradiation tests, which were conducted using the facilities of the Japan Atomic Energy Agency (JAEA). The commercial electronic devices used in the original robot systems operated long enough (more than 100 h at a 10% safety margin) in the assumed environment (100 mGy/h). Next, the usability of wireless communication in the target environment was assessed. Such tests were not possible in the target environment itself, so they were performed at the Hamaoka Daiichi Nuclear Power Plants, which are similar to the target environment. As previously predicted, the test results indicated that robust wireless communication would not be possible in the reactor buildings. It was therefore determined that a wired communication device would need to be installed. After TEPCO's official urgent mission proposal was received, the team mounted additional devices to facilitate the installation of a water gauge in the basement of the reactor buildings to determine flooding levels. While these preparations were taking place, prospective robot operators from TEPCO trained in a laboratory environment. Finally, one of the robots was delivered to the Fukushima Daiichi Nuclear Power Plants on June 20, 2011, where it performed a number of important missions inside the buildings. In this paper, the requirements for the exploration mission in the Fukushima Daiichi Nuclear Power Plants are presented, the implementation is discussed, and the results of the mission are reported.