Large Device Size Research Articles

Difference in perception of advantages and disadvantages of automated peritoneal dialysis for patients undergoing peritoneal dialysis: a conjoint analysis

BackgroundIn Japan, only less than 3% of patients undergoing maintenance dialysis select peritoneal dialysis (PD) as the mode of renal replacement therapy. Half of patients undergoing PD use a cycler for automated PD (APD). However, it remains unclear what patients undergoing PD regard as the benefits of APD. The purpose of this study was to objectively clarify what patients undergoing PD regard as the advantages and disadvantages of APD.MethodsWe designed case simulations that varied according to 6 characteristics of PD, such as the adequacy of dialysis and frequency of bag exchange, and created 16 simulation cards for conjoint analysis. For each case vignette, the respondents were asked to indicate whether they would receive this modality of PD on a 5-point scale.ResultsThirty-two patients undergoing PD were recruited for this study and completed conjoint analysis simulation questionnaires. The factor with the highest importance in evaluating the modality of PD was the frequency of bag exchange among all participants. When participants were divided into those undergoing APD and continuous ambulatory PD (CAPD), the factor was different between them; that is, the low frequency of bag exchange is regarded as an advantage of APD for patients undergoing APD, while the large-sized cycler device is regarded as a disadvantage of APD for those undergoing CAPD.ConclusionsThe perception of advantages and disadvantages of APD differed between patients undergoing APD and CAPD; the former focus on the frequency of bag exchange, whereas the latter focused the size of device.

Impact of atrial septal defect device size on biventricular global and regional function: a two-dimensional strain echocardiographic study.

In this study, we assessed the acute changes in biventricular longitudinal strain after atrial septal defect transcatheter closure and its relation to the device size. Hundred atrial septal defect patients and 40 age-matched controls were included. Echocardiography and strain study were performed at baseline and 24 hours and 1 month after the intervention. The study group was divided into two subgroups; group 1: smaller devices were used (mean device size = 1.61 ± 0.05 cm, n = 74) and group 2: larger devices were used (mean device size = 2.95 ± 0.07 cm, n = 26). At baseline, there was a significant difference between the study group and controls as regards right ventricular global longitudinal strain with significant hyperkinetic apex (p = 0.033, p = 0.020, respectively). There was a significant immediate reduction in right ventricular global longitudinal strain (from -24.43 ± 0.49% to -21.62 ± 0.47%, p < 0.001), which showed insignificant improvement after 1-month follow-up. While only left ventricular global longitudinal strain increased after 1 month. Within 24 hours of device closure, all the basal- and mid-lateral segments strains and apical right ventricular strains showed a significant reduction. There was a significant negative correlation between the indexed large device size and an immediate change in the right ventricular global longitudinal strain (r = -0.425, p = 0.034). Significant right ventricular global longitudinal strain reduction starts as early as 24 hours after transcatheter closure, irrespective of the device size used. The rapid impact of closure was mainly on the biventricular basal and lateral segments and right ventricular apical ones, especially with the large sized atrial septal defect.

Background Noise Removal Technique using Deep Learning Segmentation Network without Segmentation Map

Audio data acquired at industrial manufacturing sites often include unexpected background noise. Since the performance of data-driven models can be worse by background noise. Therefore, it is important to get rid of unwanted background noise. There are two main techniques for noise canceling in a traditional manner. One is Active Noise Canceling (ANC), which generates an inverted phase of the sound that we want to remove. The other is Passive Noise Canceling (PNC), which physically blocks the noise. However, these methods require large device size and expensive cost. Thus, we propose a deep learning-based noise canceling method. This technique was developed using audio imaging technique and deep learning segmentation network. However, the proposed model only needs the information on whether the audio contains noise or not. In other words, unlike the general segmentation technique, a pixel-wise ground truth segmentation map is not required for this method. We demonstrate to evaluate the separation using pump sound of MIMII dataset, which is open-source dataset.

Van der Waals epitaxy of nearly single-crystalline nitride films on amorphous graphene-glass wafer.

Van der Waals epitaxy provides a fertile playground for the monolithic integration of various materials for advanced electronics and optoelectronics. Here, a previously unidentified nanorod-assisted van der Waals epitaxy is developed and nearly single-crystalline GaN films are first grown on amorphous silica glass substrates using a graphene interfacial layer. The epitaxial GaN-based light-emitting diode structures, with a record internal quantum efficiency, can be readily lifted off, becoming large-size flexible devices. Without the effects of the potential field from a single-crystalline substrate, we expect this approach to be equally applicable for high-quality growth of nitrides on arbitrary substrates. Our work provides a revolutionary technology for the growth of high-quality semiconductors, thus enabling the hetero-integration of highly mismatched material systems.

Micro-focus computed tomography for turbine blade based on all-optical bremsstrahlung source

Computed tomography is a major technique for nondestructive detection of internal defects of dense materials and large-size devices. It is widely used in material science, railway, aerospace, national defense, military industry and other industries. At present, conventional high-energy industrial computed tomography system uses the X-ray source based on traditional thermionic RF electron gun, which can only provide millimeter source size, thus limiting its imaging spatial resolution. A high-energy micro-focus X-ray source is the key means to realize high-resolution high-energy industry computed tomography. As an emerging accelerator technology, the laser wakefield accelerator is a promising candidate for the micro-focus high-energy industrial computed tomography. This article reports experimental results of a micro-focus X-ray source based on laser wakefield acceleration and a computed tomography for a turbine blade. Using a 20 TW Ti: sapphire laser system, an electron beam with a charge of (140±44) pC is generated through ionization-induced injection, and then an all-optical bremsstrahlung X-ray source with an accumulated source size of 25 μm is obtained by using a 1.5 mm tungsten target. Using this source, a preliminary compressed-sensing-based computed tomography for a turbine blade is performed.

Gratingless integrated tunneling multiplexer for terahertz waves

The arrayed waveguide grating (AWG) is a versatile and scalable passive photonic multiplexer that sees widespread usage. However, the necessity of a waveguide array engenders large device size, and gratings invariably commute finite power into undesired diffraction orders. Here, we demonstrate AWG-like functionality without a grating or waveguide array, yielding benefits to compactness, bandwidth, and efficiency. To this end, we exploit optical tunneling from a dielectric waveguide to an adjacent slab in order to realize a slab-confined frequency-scanning beam, which is manipulated using in-slab beamforming techniques that we have developed in order to separate distinct frequency bands. In this way, we devise an all-intrinsic-silicon integrated 4 × 1 frequency-division terahertz multiplexer, which is shown to support aggregate data rates up to 48 Gbit/s with an on–off-keying modulation scheme, operating in the vicinity of 350 GHz. Our investigation targets the terahertz range, to provide a critical missing building block for future high-volume wireless communications networks.

Improving the computational efficiency of birefringent model based on equivalent matrix and modified permittivity

Taking advantage of optical birefringence is a promising method for manufacturing many useful devices. However, due to the multiple causes of birefringence or the large size of the birefringent devices, the numerical simulation of equal-ratio-size birefringent devices is highly inefficient. In this paper, a new method for improving the calculation efficiency of birefringent model based on equivalent matrix and modified permittivity is proposed. By calculating the equivalent matrix with scaling factor a and then modifying the permittivity, complex and large size structures are equivalent to a simple model in the simulation software. Considering the power transmittance and the authenticity of the model, the value range of a has been fully discussed. With the proposed method, simulation time and memory requirement are greatly optimized in proportion to a. We use fiber optics current sensor as an example to verify our model, and the numerical results are in close agreement with the analytical calculation.

140 W급 전력 증폭 소자의 병렬 확장형 GaN HEMT 대신호 모델

In this study, a scalable GaN HEMT large-signal model for 140-W power devices is presented. The large-signal model of an 80-finger GaN HEMT includes eight unit device models in parallel, and the large-signal model of the unit device is based on the AMCAD–FET model. The unit device includes a 10-finger GaN HEMT, a gate pad, and a drain pad. Parameters for the unit GaN HEMT model were extracted using an IVCAD program of AMCAD and a Keysight PNA-X network analyzer. The unit GaN HEMT model was verified through on-wafer load-pull measurements, and the large-signal GaN HEMT model of the large-sized 80-finger device was verified through load-pull measurements of the packaged device.

Effectiveness of selective area growth using van der Waals h-BN layer for crack-free transfer of large-size III-N devices onto arbitrary substrates

Selective Area van der Waals Epitaxy (SAVWE) of III-Nitride device has been proposed recently by our group as an enabling solution for h-BN-based device transfer. By using a patterned dielectric mask with openings slightly larger than device sizes, pick-and-place of discrete LEDs onto flexible substrates was achieved. A more detailed study is needed to understand the effect of this selective area growth on material quality, device performance and device transfer. Here we present a study performed on two types of LEDs (those grown on h-BN on patterned and unpatterned sapphire) from the epitaxial growth to device performance and thermal dissipation measurements before and after transfer. Millimeter-size LEDs were transferred to aluminum tape and to silicon substrates by van der Waals liquid capillary bonding. It is shown that patterned samples lead to a better material quality as well as improved electrical and optical device performances. In addition, patterned structures allowed for a much better transfer yield to silicon substrates than unpatterned structures. We demonstrate that SAVWE, combined with either transfer processes to soft or rigid substrates, offers an efficient, robust and low-cost heterogenous integration capability of large-size devices to silicon for photonic and electronic applications.

Ultralow-Noise Figure and High Gain Ku-Band Bulk CMOS Low-Noise Amplifier With Large-Size Transistor

This letter presents a fully integrated Ku-band low-noise amplifier (LNA) with a large-size transistor using 65-nm bulk complementary metal-oxide-semiconductor (CMOS) technology. To achieve an ultralow-noise figure, an optimization methodology balancing the ON-chip gate inductor and the parasitic capacitance of the large-size device is introduced. Using a voltage supply of 1 V, the proposed LNA has a 1.66-dB noise figure and 32.48-dB gain and, thus, outperforms other reported Ku-band bulk CMOS LNAs in these two respects. The LNA achieves the highest figure of merit I among reported Ku-band CMOS, silicon germanium, and gallium arsenide heterojunction bipolar transistor LNAs. The LNA consumes a dc power of 22 mW and occupies a core area of 0.58 × 0.43 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .

X-ray metal material evaluation using an SOI pixel detector

The technology for evaluation of metal materials encompasses machine parts and structures. Residual stress is one indicator used for evaluating the strength and stiffness of metal materials. X-ray residual stress measurement is a non-destructive, non-contact, and precise method in various residual stress measurement methods. This method is used only for research purposes because of its long measurement time and large device size. Therefore, we developed a small, high-speed X-ray residual stress measurement device with a charge-integration-type silicon-on-insulator (SOI) pixel detector, INTPIX4, for industrial use.Previous studies have shown that residual stress can be measured in less than 1 s by using a measurement device with an SOI pixel detector. In this study, we report a more detailed specification of the measurement device and consider its availability for metal material evaluation.

The Effect of Polymeric Binders in the Sulfur Cathode on the Cycling Performance for Lithium-Sulfur Batteries

Recently, great advance of the Li-S battery technology enables its penetration to the power source of the mid- and large-sized devices, which require high energy and power density that cannot be achieved in the Li-ion battery. While the most successful sulfur cathode could be designed by the optimization of the composite structure with carbonaceous materials, the binder system has been recently considered another important factor because the electrode structure of the sulfur cathode suffers huge structural change during the repeated electrochemical cycles. We studied the structural and electrochemical performance of the sulfur cathodes prepared by two different binders, the water-soluble SBR/CMC mixture binder and the traditional PVdF binder. The enhanced battery performance was observed in the SBR/CMC-based electrode and its origin was investigated by post mortem analysis about the electrodes, which confirmed the better mechanical integrity in the electrode compared with the PVdF-based electrode.

Venous flow patterns after percutaneous atrial septal defect closure: Does the mechanical device decrease right atrial compliance?

Systemic venous flow patterns become abnormal and restrictive after surgical closure of ostium secundum atrial septal defect (ASD) but rarely studied after percutaneous device closure. From January 2017 to January 2018, systemic venous Doppler flow patterns were documented prospectively in 50 subjects who underwent percutaneous closure of ASD, prior to, after procedure, and at 6-month follow-up and correlated with defect size and device size. In hepatic veins and superior venacava post device-closure closure, the velocity time integral (VTI) of forward flow in both systole (S) and diastole (D) increased. Overall S was higher than D, and D/S ratio was <1. The D/S ratio increased after device closure significantly reflecting that the improvement in atrial filling increase in diastolic flow more than the increase in systolic flow. Increase in flow velocities was more prominent at 6months with further increase in D/S VTI ratios. When correlated with the defect size, in those with defect size less than 15mm/sq.m (mean device size 13.05±3.21mm), the changes in S- or D-wave, D/S ratio were less prominent and statistically not significant, while in subjects with defect size≥15mm/sq.m (mean device size 23.02 (±4.77mm), these changes were greater and statistical significant. Residual filling defects with restriction of systolic venous flow were observed in subjects after device closure, correlating with larger device sizes, implying the compliance abnormality conferred by them which progresses at 6months. Subjects with persistent abnormalities would need careful follow up for incomplete remodeling and increase in atrial size related arrhythmias.

Transient Electromagnetic Voltage Imaging of Dense UXO-Like Targets Based on Improved Mathematical Morphology

Unexploded ordnance (UXO) survey is the foremost task of clearance project. Transient electromagnetic method (TEM) is proved effective for UXO survey. However, it is still difficult for TEM to detect small-size, ultra-shallow and dense UXO targets because the large-size devices and inversion methods for large-scale applications are usually ineffective. In the work, in order to avoid the complex inversion of apparent resistivity, the voltages acquired by our specified small-loop TEM system are used to depict a voltage distribution profile, which is then processed with an improved imaging algorithm. Several major influences on the secondary voltage image are discussed during UXO survey, including emitting coil size, target attitude, basin effect and shell thickness. Furthermore, an improved watershed imaging algorithm is proposed to obtain the best threshold marking and automatically realize the dense target discrimination. Over-segmentation resulting from burrs, noises, and scraps is reduced through background marking. And also under-segmentation is avoided during foreground marking through adaptive search of saddle point. The algorithm has been verified effective using simulation data and experiment data of UXO-like targets.

Exploration of polymer-assisted crystallization kinetics in CsPbBr3 all-inorganic solar cell

• The compact CsPbBr 3 layer with pure phase was obtained. • The PCE of 7.8% is the highest efficiency of CsPbBr 3 based device via one step process. • The tandem solar cells present no degradation after 120 h UV aging test. All-inorganic perovskite material (CsPbBr 3 ) has attracted enormous attention in photovoltaic devices due to superior stability. However, the thickness of CsPbBr 3 film beyond 100 nm suffers from poor morphology, impurity phase and defects due to unbalance between fast growth and slow nucleation of film. Here, we introduce polyethylene glycol (PEG) into solution to achieve compact CsPbBr 3 film with pure phase via a simple one-step solution process. The Lewis base of PEG interacts with the Lewis acid of Pb 2+ to reduce the cluster size of CsBr-PbBr 2 -DMSO colloids as well as to increase the nucleation rate. The CsPbBr 3 film magnitude less in intrinsic defect concentration is obtained by the addition of PEG. The open-circuit voltage increases from 1.15 eV to 1.41 eV with the highest efficiency of 7.8% as a result of less charge recombination of device, which is the highest efficiency ever recorded in one step solution process. The current–voltage curves measured at five different positions of large size device based on PEG (100 mm 2 ) were almost identical, indicating highly uniform of devices. Thanks to the high quality of PEG modified CsPbBr 3 film, there is no efficiency reduction during 120 h UV illumination. It was further used as a UV filter in tandem device which effectively restricts the UV degradation of bottom organic-inorganic perovskite solar cell. The tandem solar cell still remains 93% of the initial PCE after 120 h UV aging test, which are the main routes for commercializing device.

A Critical Step to Using a Parametric Array Loudspeaker in Mobile Devices.

A parametric array (PA) loudspeaker is a highly directional audio source that might grant one's convenience if it is used with mobile devices. However, conventional PA loudspeakers is almost impossible to apply in mobile devices using a battery because of the large power consumption and large device size. In this study, a PA loudspeaker system (PALS) was fabricated and evaluated to show that those difficulties could be overcome to apply it to mobile devices. In order to construct a PALS for demonstration, a power amplifier and signal-processing unit should also be properly designed and built. The PA source transducer should also be designed and built for a mobile device application. These components were integrated into a single PALS. The PALS generated a 125-dB primary wave and 62 dB of a different frequency wave (DFW) through the PA at 0.45 m in a 3 m × 3 m × 2 m semi-anechoic chamber. We confirmed that the half-power bandwidth (HPBW) formed a 6° beam at 83 kHz of DFW and 90 kHz of the primary wave (PW), and the HPBW formed a 7.3° beam at 5 kHz of DFW and a 7.1° beam at 10 kHz of DFW, respectively. Lastly, the power required was 6.65 W without a matching circuit, and 3.25 W with such a circuit.

Cathode Additive for LiNi0.8Co0.1Mn0.1O2 /Li Metal Battery Operating at 4.3V

Lithium-ion batteries (LIBs) are widely used in portable electronics. However, safe, long-term stable LIBs with higher energy density need to be developed to meet the increasing demand for large-sized devices such as electric vehicles and energy storage systems. For high energy density, further development of cathode materials is still considered as capacity and/or operating voltage are pursued. Among the various cathode materials, Ni-rich LiNixCoyMn1-x.yO2 materials with x ≥ 5, especially LiNi0.8Co0.1Mn0.1O2 (NCM811) have attracted much attention recently owing to their high theoretical specific capacity of 200 mAh/g. However, LiNi8Co0.1Mn0.1O2 operated beyond 4.3V suffers serious capacity fading caused by continuous electrolyte decomposition, despite an increase in the capacity in the early cycles. To overcome this obstacle, the addition of small amounts of other components into the electrolyte system without changing the bulk properties is a very promising approach. In this study, we introduced a cathode additive and investigated the effect of functional electrolyte for the application NCM811 based Lithium metal batteries. Our results indicate the significance of novel additive for promising high voltage operation of next-generation cathode materials.

Analytical Noise Optimization of Single-/Dual-Band MOS LNAs With Substrate and Metal Loss Effects of Inductors

Analytical noise formulations and design optimization of single- and dual-band inductively source-degenerated MOS low-noise amplifiers (LNAs) with the substrate and metal loss effects of on-chip inductors are established in this paper. It reveals that the noise figures of both single-/dual-band LNAs degrade substantially under the consideration of the loss effects. However, by increasing the device size, the noise optimization methodology of simultaneous noise and input match for a single-band LNA still holds true with concern for the loss effects. For a dual-band LNA, analytical noise optimization for a balanced noise design is established for inductors with metal and substrate loss and indicates a larger device size. The substrate and metal loss effects of inductors can be mitigated using integrated passive device (IPD) process for the input match network. The demonstrated single-band 0.18- $\mu \text{m}$ MOS LNAs with and without IPD process show noise figures of 1.53 and 2.52 dB at 2.4 GHz, respectively. Subsequently, the implemented dual-band 0.18- $\mu \text{m}$ MOS LNAs with and without IPD process show noise figures of 1.6/2.6 and 3.25/4.1 dB at 2.4/5 GHz, respectively.

Highly-Efficient Solution-Processed Organic Light Emitting Diodes with Blend V2O5-PEDOT:PSS Hole-Injection/Hole-Transport Layer

ABSTRACTOrganic light-emitting diodes (OLEDs) have attracted huge concern because of their intrinsic characteristics and ability to reach the pinnacle in the field of high-quality flat-panel displays and energy-efficient solid-state lighting. High-efficiency is always a key crux for OLED devices being energy-saving and longer life-span. OLEDs have encountered enormous difficulties in meeting the requirements for large-sized devices due to a major limitation in vacuum thermal evaporation technology. In multilayered OLED devices, the characteristics of the charge injection/transport layer is a crucial factor for the operating-voltage, power-efficiency and stability of the device. Transition metal oxides have shown great potential owing to their wide range of possible energy level alignments, balanced charge injection, and improvement of carrier mobilities. In this study, we report a solution-processed blend V2O5-PEDOT:PSS hole-injection/hole-transport layer (HIL/HTL) for efficient orange phosphorescent OLEDs. The electroluminescent characteristics of blend V2O5-PEDOT:PSS based devices were studied with the structure ITO/V2O5-PEDOT:PSS/CBP:Ir(2-phq)3/TPBi/LiF/Al. The V2O5-PEDOT:PSS based OLEDs displayed relatively higher device performance and low roll-off than that of the counter PEDOT:PSS device in terms of a maximum luminance of 17,670 cd m-2, power efficiency of 19.4 lm W-1, external quantum efficiency of 8.7%, and more importantly, low turn-on voltage. These results demonstrate an alternative approach based on metal oxide/organic blend HIL/HTL as a substitute of PEDOT:PSS for high-efficiency solution process OLEDs.

Development of a robotic walker for individuals with cerebral palsy

Objective: This study describes the first use of a robotic walker in youth and young adults with cerebral palsy (CP) Gross Motor Function Classification (GMFCS) IV.Methods: Semi-structured interviews were conducted before and after each robotic walker trial. Interviews were recorded, then transcribed and subjected to thematic analysis.Results: Five participants (4 male, 13–22 years of age) with quadriplegia secondary to CP were recruited. Four individuals with mixed tone quadriplegia GMFCS IV were able to independently walk with the device. One individual with significant dyskinesia was unable to utilize the device. The assessment team included two physiotherapists, an occupational therapist, a physiatrist and three engineers. Major themes related to physical and social impacts were identified. Some physical advantages include the ability to walk hands-free and promotion of physical fitness. Examples of physical barriers include limited harness design and large device size. Social advantages include increased independence and peer engagement. Finally, a social disadvantage identified was limited use on uneven terrains.Discussion: Suggestions for modifications for identified challenges and disadvantages include decreasing the size of the robotic walker, more harness designs, decreasing the force required to take an initial step, adding a joy stick for user control and creating a more versatile base that can be used on different terrains such as ice or baseball fields.Conclusion: Robotics holds great hope for individuals with CP where mobility options are limited. Physical and social advantages are evident. Recommendations for future improvement and studies of use in exercise and participation are provided.IMPLICATIONS FOR REHABILITATIONAs youth and young adults with cerebral palsy age, options for mobilization can become limited with challenges in placing them in a walking device due to size and numerous other physical limitations.A robotic walker with a built-in mechanical lift is available for individuals with cerebral palsy.This study was able to gather important information and recommendations to tailor a new robotic walker prototype specifically for individuals with cerebral palsy.