Devices Of Different Sizes Research Articles

Numerical study of divertor detachment in TCV H-mode scenarios

The effect of divertor closure and nitrogen seeding on the detachment process has been studied by performing 2D numerical simulations of tokamak à configuration variable (TCV) H-mode divertor scenarios with the SOLEDGE3X-EIRENE edge plasma transport code. The simulations reveal that, in the cases with only deuterium gas fuelling, detachment occurs at a similar level of divertor neutral pressure (0.76 Pa), despite the difference in divertor closure achieved by changing the length of the outer baffle. Nitrogen reduces the target temperature with little effect on the upstream density and momentum loss but drops the upstream pressure, leading to a decrease in the target particle flux and divertor neutral pressure. Furthermore, when the radiation front starts to move up from the outer target, the peak parallel heat flux level at the outer target remains approximately the same ( MW m−2), regardless of whether it is a deuterium fuelling scan, a nitrogen seeding scan at a fixed fuelling rate, or a change in the length of the outer baffle. An empirical partial detachment qualifier calibrated on AUG experimental data was compared with the TCV simulations. The results show good agreement in detachment state prediction, indicating the potential of this detachment qualifier to be applied in devices of different sizes, emphasizing the combined influence of input power entering the divertor, neutral pressure, and the concentration and species of impurity in achieving divertor detachment.

Quantitative radial force measurements of Woven EndoBridge devices.

Lateral/radial forces and the mechanical properties of Woven EndoBridge (WEB) devices have significant importance for therapeutic success. In other words, adequate apposition of the lateral wall of a cerebral aneurysm is critical for preventing recurrence or re-rupture risk. This study aimed to investigate the pressure values applied by different WEB devices to the lateral walls of aneurysms and the relationships between these pressure measurements and the diameters of WEB devices. By placing four WEB devices of different sizes and types between two rigid metal plates, the lateral forces applied by these WEB devices to plates of different apertures were measured quantitatively. We tested a single device of each size over multiple periods. The total number of examined WEB devices is four. There was a significant negative relationship between plate distances and pressure values (correlation coefficient:-0.956, p = 0.000). The lateral wall apposition pressure of a 4- or 5-mm aperture size was higher than a 6-mm aperture size for SL-type WEB devices with a 7-mm diameter. Similarly, the lateral wall apposition pressure detected for a 3- or 3.5-mm aperture size was higher than a 4-mm aperture size for W5-4.5-3 and W5-5-3.6. It was observed that maximum lateral wall pressure was detected in plate measurements of SLS-type devices compared to SL-type devices. The diameter and height values of 3 of the 4 unconstrained WEB devices analyzed differed from the catalog values. It seems that SLS-type devices apply more pressure on the aneurysm's lateral borders than SL-type devices.

Optimization of heterogeneous arrays of wave energy converters

Optimizing the layout of devices in an array of wave energy converters (WECs) is one of the core aspects of WEC array design. More often than not, WEC arrays are designed to contain identical devices. However, to further improve power generation, this paper investigates how devices of varying dimensions can affect the overall performance of the array; the array containing devices of different sizes is referred to as a heterogeneous array in this work. The heterogeneity is achieved by varying the radius and draught of cylindrical buoys. We measured the performance of the heterogeneous array against the homogeneous array containing the same number of devices in an identical layout, assuming the summation of volumes of all devices is the same for both the heterogeneous and the homogeneous arrays. The power from the array is computed using a time-domain array dynamic model and an optimal constrained control. The hydrodynamic coefficients used as input in the dynamic model are computed using a semi-analytical method to enable computationally efficient optimization. The optimization was performed using a genetic algorithm. Arrays of 3, 5, and 7 devices are presented in this paper. For the tested wave conditions, it was found that in some wave conditions a heterogeneous array can achieve a performance improvement of up to 40% over the corresponding homogeneous array.

Effect of plot size and precipitation magnitudes on the activation of soil erosion processes using simulated rainfall experiments in vineyards

Soil erosion is recognized as a threat to humankind and to natural ecosystems when sustainable limits are exceeded. Several researchers have used various tools, such as rainfall simulators, to assess extreme rainfall events and non-sustainable soil management practices. However, combinations of two different devices of different sizes has not been tested before, especially in vineyards. The aim is to verify whether plot size, connectivity processes and rainfall distribution affect the activation of soil erosion. In this research on soils cultivated with vineyards in the Moravia Region in the south-eastern part of the Czech Republic, we have performed various rainfall simulation experiments with a small device (1 × 1 m) and with a large device (8 × 1 m). Our results show that the surface runoff was approximately 30% higher on the small plot than on the large plot. The large rainfall simulator produced sediment concentration that was up to 3 times higher, and soil loss that was up to 1.5 times higher, even when the surface runoff was 30%–50% lower for the large rainfall simulator. We therefore conclude that there is a clear influence of surface length and plot size on surface runoff, soil loss and sediment concentration activation. When planning their experiments, researchers need to consider that the type of device can have a drastic influence on the final results. Two devices subjected to the same rainfall intensity (60 mm h−1) can produce very different results, e.g., depending on plot size and kinetic energy. Our results can be effectively used to plan soil protection measures and to inform local authorities about areas prone to flooding and about loss of sediments.

Random lasing of the active organic nanocrystals of SFX-2-7-DDPA solution

In this paper, we demonstrated organic nanocrystals micro-lasers devices with different thickness from 0.4mm to 0.7mm. The N2, N2, N7, N7-tetraphenylspiro [fluorene-9,9-xanthene]-2,7-diamine, 95% (SFX-2-7-DDPA) structure (organic nanocrystals in a solution)- highly scattering medium is manipulated to generate a multiple light scattering. The manufacture technique can be used to a variety of water soluble SFX-2-7-DDPA, designed to work in the gain ethanol solution with SFX-2-7-DDPA nanocrystals devices, has been investigated at different input powers. A Nd-YAG laser based experiment tool has been measured including a from amplified spontaneous emission to random lasing. The analysis of photon travel distance has been thought about showing the random lasing behavior with particular attention on lasing tunability by using devices of different sizes. Particulary,for first time, we have demonstrated dye-doped SFX-2-7-DDPA nanocrystals based organic random lasers.

The size and temperature effect of ideality factor in GaN/InGaN multiple quantum wells micro‐light‐emitting diodes

AbstractIn this paper, the GaN/InGaN multiple quantum wells (MQWs) micro‐light‐emitting diode (micro‐LED) devices of different size with green light emission were fabricated. The ideality factor of micro‐LED was discussed. For temperature‐dependent electrical characterization, the current–voltage relationship within a temperature category of 303–573 K was measured. The contact resistance between electrodes and GaN was exhibited, and a favorable ohmic contact was achieved for p‐electrode and p‐GaN. Next, the temperature and size effect of ideality factor was demonstrated. All size devices showed an extremely low factor smaller than 1.9. In order to better evaluate the temperature dependence, the thermal characterization was performed with a constant current and voltage mode. The 80‐μm device revealed a satisfactory temperature coefficient, namely, 1.92 mV/K at the forward voltage and 2.66 kA·K at the reverse bias. For temperature‐dependent optical characterization, the irradiance and brightness from 303 to 453 K of 100 μm were demonstrated. Even at 453 K, the brightness is still favorable as 34,520 nits. Following this, the luminous efficiency droop with increasing injection current density was described and discussed.

Using extractables data from single-use components for extrapolation to process equipment-related leachables: The toolbox and justifications

Quantitative information on process equipment-related leachables (PERLs) is required for process qualification and within a safety assessment. Extractables data for single-use equipment are suitable and applicable if the extractables study conditions fit or are bracketing the expected conditions of use. It is necessary to extrapolate extractables data when the expected in-use conditions are not covered by the test conditions. Methods for such quantitative extrapolation of extractables data toward potential PERLs are therefore needed. They are comprehensively described in this publication and include: scaling of extractables data for devices of different sizes adjusted to process-volumes, extrapolation to temperatures different from the extraction temperature, extrapolations to different solvent compositions, extrapolation to various contact times, and the combination of extractables data from individual components to assess assemblies. These extrapolation methods yield extractables data as if an extractables study had been performed.The methods presented are consistently derived from basic physicochemical principles. The relevant, underlying physical parameters are obtained from extractables experiments and are compared with published data. The applicability and justification of the proposed calculation methods are discussed and benchmarked against experimental findings.

Magnetic nanofluid: synthesis and characterization

Dispersing nanoparticles in the liquid significantly alters the transport properties of the resulting fluids. Conventional coolants such as water and oils have comparatively low thermal conductivities and offer somewhat limited heat transfer coefficients to accomplish the typical cooling applications. Dispersed nanoparticles with higher thermal conductivity provide better transport properties leading to enhanced heat transfer coefficients in many devices of different size. Nanofluids which contain nanoparticles dispersed in continuous liquid phase provide many promising properties as compared to conventional fluids. In the present work, we prepared magnetic nanoparticles by the co-precipitation, followed by ultrasonication and coating with oleic acid, which were ultimately dispersed in kerosene as a carrier fluid. The agglomeration of the coated particles was thus prevented to improve their stability. The samples were analysed with various sophisticated techniques such as high-resolution transmission electron microscopy, field emission scanning electron microscopy, dynamic light scattering, zeta potential, X-ray diffraction, Fourier transform infrared spectra, thermogravimetric analysis, rheometry, and superconducting quantum interference device. The coated magnetic nanoparticles showed weak attraction force and offered reasonable colloidal stability of the nanofluid.

Different Rescue Approaches of Migrated Woven Endobridge (WEB) Devices: an Animal Study

PurposeTreatment of wide-necked intracranial aneurysms using the Woven Endobridge (WEB) device has become broadly accepted. Feared complications with the potential of increased poor clinical outcome include dislocations and migration of the device. This study was carried out to determine the effectiveness of a variety of different strategies to rescue migrated WEB devices.MethodsIn a porcine model, WEB devices of different sizes (SL [single layer] 3.5 × 2mm and SL 4.0 × 3 mm, SL 8 × 5 mm and SLS 8 mm [single layer spherical]) were placed into both the subclavian and axillary arteries. A total of 32 rescue maneuvers (8 per rescue device) were performed. Small WEBs were rescued using reperfusion catheters (RC) (SOFIA Plus and JET 7), larger WEBs were rescued using dedicated rescue devices (Microsnare and Alligator). Rescue rates, times, attempts and complications were assessed.ResultsRescue attempts of migrated WEBs were successful in all cases (100%). Rescue time (p = 0.421) and attempts (p = 0.619) of small WEBs using RCs were comparable without significant differences. Aspiration alone was not successful for larger WEBs. Rescue of larger WEBs was slightly faster (122.75 ± 41.15 s vs. 137.50 ± 54.46 s) with fewer attempts (1 vs. 1.37) when using the Microsnare compared to the Alligator device. Complications such as entrapment of the WEB in the RCs, vasospasm, perforation, or dissection were not observed.ConclusionRescue of migrated WEB devices is a feasible and effective method and 100% successful rescue rates and appropriate rescue times can be achieved for small WEBs using RCs and for larger WEBs using dedicated rescue devices (Microsnare and Alligator).

A Study on Head Flexion During Mobile Device Usage: An Examination of Sitting, Standing, and Lying Down Positions

The purpose of this study was to examine the effects of mobile device screen size and different positions on head posture. Participants’ angle of head flexion was measured when they were sitting, lying on their back, and standing while using mobile devices of different sizes. Results showed that participants had a greater head flexion when standing compared to both sitting and lying down. However, there were no significant differences in head flexion while participants used mobile devices of different sizes. There were no sex differences in the sitting and standing conditions. For lying down, females had a significantly greater angle of head flexion compared to males. Future research should examine sex differences in physical body structure to have a better understanding of the physical complications associated with device usage. Consumers should be advised how certain positions lead to greater head flexion, which could lead to greater musculoskeletal pain.

Study of Hole-Transporter-Free Perovskite Solar Cells based on Fully Printable Components.

Hole-transporter-free perovskite solar cells carrying a carbon back contact electrode provide the possibility of making full printable low cost and stable devices, even though their efficiency is substantially lower than those made in the standard configuration. The present work searched for simple and easy routes for constructing such devices, demonstrating that organic components do enhance device efficiency but only to a level that is not worth the trouble nor the cost. Devices based on a triple mesoporous layer of titania/zirconia/carbon with perovskite infiltration gave an efficiency of 10.7%. After 180 days of storing under ambient conditions, a small loss of efficiency has been observed for a cell made in June, in spite of the fact that in going from June to December, a large increase of the ambient humidity took place, thus verifying the protective effect that the carbon electrode is providing. The addition of spiro-OMeTAD to the hole-transporter-free device resulted in increasing the efficiency by about 10%, a change which is appreciated to be of low importance given the cost of this material. This increase mainly derived from an increase in the current. Devices of different sizes have been constructed by screen printing, using home-made pastes for all the components making the cell scaffold, i.e., for titania, zirconia, and carbon layers.

Reflection symmetry aware image retargeting

Reflection symmetry is one of the most commonly occurring and prominent visual attributes present in the real world. With an increase in the display devices of different sizes and aspect ratios, the images captured from the real world need to be resized to fit to the display device. In this paper, we propose a novel image retargeting approach which preserves the reflection symmetry present in the image during the image retargeting process. We detect the symmetry region present in the image using symmetry axis detection and object proposals. We propose a novel framework for finding an optimized reflected seam for the least energy seam defined by the seam carving approach. The symmetry axis and the symmetric object are preserved by adding or removing a seam and its reflected counterpart together. We show better preservation of symmetry axis, preservation of shape of the symmetric object, and quality of image retargeting when compared to the existing methods using three quantitative measures along with the qualitative results.

Comparison of ionization track structure models for electronic devices of different sizes

The effect of the ionization track structure of the heavy ion deposited charge by direct ionization on the energy deposition calculation for single event upset (SEU) rate prediction is investigated using Geant4 based on Monte Carlo transport code. The limitations of using linear energy transfer (LET) as the single parameter to determine the energy deposited in the sensitive volume (SV) are analyzed. Track effects are becoming of great importance with technology downscaling. Three track structure models are summarized, and the applicability of track structure models for high energy ions (>8.0 MeV/amu) and low energy ions (<0.3 MeV/amu) with the same LET to devices of different sizes is discussed. It is revealed that the selection of an appropriate track structure model requires a comprehensive consideration of electronic device size and ion energy.

Results of four European round-robins on short-circuit current temperature coefficient measurements of photovoltaic devices of different size

Within the EURAMET ENG55 “PhotoClass” project, several characteristics of photovoltaic (PV) devices beyond their performance at Standard Test Conditions were investigated, including measurements at varying irradiance and temperature. Four groups of PV devices of different size and technology were prepared and corresponding round-robins were run between partner laboratories with substantially different facilities and methods – namely based on spectral or integral measurements. This paper presents the outcome of the four inter-laboratory comparisons dealing with temperature coefficient measurements of the short-circuit current of PV devices, from reference-cell size to full-size commercial modules of mainly several c-Si technologies, but also with some examples of CIGS and GaAs devices. The measurement results are compared via En number assessment, hence including measurement uncertainties. The main outcome of this measurement exercise is a very good agreement of all the laboratories although completely different approaches were applied. In some cases, laboratory measurement uncertainties are even considered rather conservative and could therefore be revised. Furthermore, a comparison between bare cells and commercial modules of the same technology is made, which may represent useful information for PV manufacturers.

Study of Dissipative Losses in AC-Biased Mo/Au Bilayer Transition-Edge Sensors

We are developing kilo-pixel arrays of transition-edge sensors (TESs) for the X-ray Integral Field Unit on ESA’s Athena observatory. Previous measurements of AC-biased Mo/Au TESs have highlighted a frequency-dependent loss mechanism that results in broader transitions and worse spectral performance compared to the same devices measured under DC bias. In order to better understand the nature of this loss, we are now studying TES pixels in different geometric configurations. We present measurements on devices of different sizes and with different metal features used for noise mitigation and X-ray absorption. Our results show how the loss mechanism is strongly dependent upon the amount of metal in close proximity to the sensor and can be attributed to induced eddy current coupling to these features. We present a finite element model that successfully reproduces the magnitude and geometry dependence of the losses. Using this model, we present mitigation strategies that should reduce the losses to an acceptable level.

Retrieval of large Occlutech Figula Flex septal defect occluders using a commercially available bioptome: proof of concept.

This study aimed to develop a method for retrieval of the new meshed nitinol atrial septal defect occluders - Ceraflex and Occlutech. The newly developed atrial septal defect occluders have potential benefits considering implantation, but concerns regarding their removal in case of embolisation have been raised. Over 21 years, 1449 patients underwent interventional atrial septal defect occlusion in our institution. We reviewed the cases of embolisation of the device, developed a strategy for device removal, and tested it on the benchside and in animal tests. In 11 patients (0.8%), the intended atrial septal defect occlusion was complicated by an embolisation of the device. In contrast to the Amplatzer septal occluders, retrieval of Occlutech devices larger than 16 mm with snare techniques was impossible. In benchside tests, this was confirmed and a new method for removal of large meshed devices was developed. This involved the commercially available Maslanka® biopsy forceps. The feasibility of this technique in vivo was tested in a pig model. During animal tests, using the Maslanka biopsy forceps it was possible to interventionally retrieve embolised Ceraflex and Occlutech devices of different sizes - 10, 16, 30, and 40 mm - into a 12-F sheath. It was impossible to retrieve Occlutech and Ceraflex devices larger than 16 mm into a large sheath in vivo and during benchside tests. However, this was feasible on the bench and in vivo using the Maslanka biopsy forceps even with the largest available devices.

Ferrofluid based composite fluids: Magnetorheological properties correlated by Mason and Casson numbers

Comprehensive flow and magnetization data obtained previously on the behavior of ferrofluid based magnetorheological fluids (FF-MRF) [Susan-Resiga and Vékás, Rheol. Acta 55(7), 581–595 (2016)] were correlated using a Mason number ( M n) defined for these nano-micro composite fluids and the corresponding Casson (Ca) number, instead of the Bingham number used for conventional magnetorheological (MR) fluids. Practically, agglomerate-free, high colloidal stability ferrofluids with Newtonian behavior in the absence of a magnetic field were used as carrier to keep the off-state viscosity as low as possible and to ensure the reproducibility of the MR response of the composite fluid. The apparent viscosities and magnetization values for samples with various nanosized magnetites and micrometer range iron particle volume fractions (from 2.75% to 22.90% and from 4% to 44%, respectively) at different values of magnetic induction and shear rate collapsed on a master curve by using the nondimensional M n and Ca numbers to correlate the measured data. By controlling the volume fraction both at nano- and microlevels, the magnetic and MR properties of the resulting composite fluids can be tailored to offer a high-performance lubricant for semiactive dampers and brakes, as well as for magnetofluidic rotating seals. The M n and Ca numbers offer a design metric based solely on the properties of FF-MRFs and can be reliably scaled to devices of different sizes and operating conditions.

Design for personalized mobile health applications for enhanced older people participation

BackgroundToday's digital society opens opportunities for the development of mobile health applications to support the medical care. Methods and resultsAs a design example, an Android app is written for the Android ecosystem (Google, Mountain View, CA) using Android Studio as the integrated development environment and allows in this way for widespread implementation on personal devices of different sizes (smartphone, tablet). The resulting app is able to record the medication intake, log physiological parameters and perform cognitive assessment. In an additional step, the app is personalized by incorporating personal data (pictures of friends, family, hobbies…) in the assessment tests for cognitive functions. As this data becomes more and more available from social media, it can be easily integrated in these types of apps. ConclusionDue to this personalization, the older people participation is expected to enhance, a crucial aspect needed for the future widespread deployment of these systems.

Modeling and characterization of PCB coils for inductive wireless charging

Wireless charging is emerging as a viable technology in many industries, including consumer, medical, and sensor electronics. An investigation of design principles is conducted for a wireless charging platform that is designed to charge devices of different sizes and technologies, using only through vias. It is shown that at a 5 mm separation distance, a coupling coefficient can be achieved which varies from 0.12 to 0.37 when staggered hexagonal transmitter coils (approximately 5 cm across) are used with an unstaggered square receiver coil, which declines to 0.06–0.11 at 2 cm separation. Without design measures, the coupling coefficient will approach zero at certain positions. The quality factors of the coils can be improved by stacking the coils in parallel, enabling the use of only through-vias, while the inductance can be controlled horizontally by increasing the number of turns in the inductor.

A new explicit and analytical model for square Gate-All-Around MOSFETs with rounded corners

The scaling of MOSFET transistors makes the use of new device geometries, such as multigate FETs, a need to solve the limitations of the conventional bulk technology. In this context we introduce an analytical model for square Gate All Around (GAA) MOSFETs with rounded corners including quantum effects. The modeling of rounded corners in GAA and FinFET devices is imperative because there are no perfectly square corners in the cross-section of real devices. In this model the 2D inversion charge distribution function (ICDF) is described analytically for devices of different sizes and for different operation regimes. The model reproduces accurately simulated data obtained with a state-of-the-art simulator that solves self-consistently the Poisson and Schrödinger equations in the devices under consideration. The analytical ICDF is used to better understand the device physics and to calculate the inversion charge centroid and the gate-to-channel capacitance for different device geometries and biases for modeling purposes.