Improvement of PEFC Cell Performance With a Movable Rib

2011 ◽  
Author(s):  
Hirofumi Tanigawa ◽  
Ryoji Hakataya ◽  
Takaharu Tsuruta
Keyword(s):  
Water Management ◽  
Experimental Study ◽  
High Performance ◽  
High Reliability ◽  
Cell Performance ◽  
Water Behavior ◽  
Control Water ◽  
Better Than

Water management is very important in the development of the PEFC with high performance and high reliability. We found that the moisturizing effect in the straight-type channel is marked as compared with the serpentine-type channels, and the draining performance in the serpentine-type channel is better than that in the straight-type channel. Then, we have developed the movable rib which can change the position of the rib manually. Experimental study shows that the movable rib can control water behavior and can improve the cell performance.

Examination of a non-orthogonal multiple access scheme for next generation wireless networks

2020 ◽  
pp. 154851292095127
Author(s):  
Ravi Shankar
Keyword(s):  
Multiple Access ◽  
High Performance ◽  
High Reliability ◽  
Wireless Systems ◽  
Bandwidth Efficiency ◽  
Fifth Generation ◽  
Access Scheme ◽  
Simulation Results ◽  
The Relationship ◽  
Better Than

Non-orthogonal multiple access (NOMA) is an important technique that enables fifth-generation (5G) wireless systems to satisfy the heterogeneous requirements of enhanced fairness, huge connectivity, high performance, low latency, and high reliability. In this work, the NOMA technique for 5G wireless communication is investigated, and considering user fairness limitations, the channel capacity has been optimized. Also, bandwidth efficiency (BE) is examined and the relationship between BE and energy efficiency (EE) is derived. Simulation results show that without wasting power the near user gets preference in power allocation when the target rate is greater than 6.4 bps/Hz. Also, when the target rate [Formula: see text] 6.4 bps/Hz, the outage performance of the near user will improve and the performance of the far user will remain the same. Also, it is demonstrated that cooperative NOMA outperforms all other techniques. Simulation outcomes confirm that NOMA performs better than conventional multiple access techniques in terms of EE and BE.

scholarly journals Influence of Local Sand on the Physicomechanical Comportment and Durability of High Performance Concrete

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Nadia Tebbal ◽  
Zine El Abidine Rahmouni
Keyword(s):  
Experimental Study ◽  
High Performance ◽  
Sand Dune ◽  
High Performance Concrete ◽  
Specification Tests ◽  
Mechanical Strengths ◽  
Better Than

This research consists of incorporating the crushed sand (CS) in the composition of a concrete and studies the effect of its gradual replacement by the sand dune (SD) on sustainability of high performance concrete (HPC) in aggressive environments. The experimental study shows that the parameters of workability of HPC are improved when the CS is partially replaced by the SD (<2/3). However, a high content of SD (>1/3) additional quantities of water is needed to meet the workability properties. The mechanical strengths decrease by adding the SD to CS, but they reach acceptable values with CS in moderate dosages. The HPC performances are significantly better than the control concrete made up with the same aggregates. The specification tests of durability show that the water absorbing coefficients by capillarity increase after adding SD to the CS.

Experimental Study on Permeability and Chloride Resistance Properties of Concrete in Yu-Cheng Bridge

2012 ◽  
Vol 204-208 ◽  
pp. 2253-2256
Author(s):  
Tao Fan ◽  
Jian Feng Dong ◽  
Yu Xi Zhao
Keyword(s):  
Experimental Study ◽  
Water Absorption ◽  
High Performance ◽  
High Performance Concrete ◽  
Salt Spray ◽  
Air Permeability ◽  
Normal Concrete ◽  
Chloride Resistance ◽  
The Relationship ◽  
Better Than

This paper studies air permeability, water absorption and chloride resistance properties of the normal concrete (NC) and the high performance concrete (HPC) adopted in the Yu-Cheng Bridge, Zhejiang Province. The air permeability and water absorption were measured by Autoclam, while the chloride resistance were tested by RCT after accelerate chloride ingression in the salt spray cabinet. The relationship among the air permeability, the water absorption and the chloride resistance of both kinds of concrete were analyzed. According to the result of Autoclam, HPC shows better resistance abilities of air permeability and water absorption, and this indicates that HPC is denser than NC. RCT shows that the chloride resistance of HPC is better than that of normal concrete.

Advances in imaging SIMS studies of stained and BrdU-labelled human metaphase chromosomes

1995 ◽  
Vol 53 ◽  
pp. 932-933
Author(s):  
R. Levi-Setti ◽  
J. M. Chabala ◽  
R. Espinosa ◽  
M. M. Le Beau
Keyword(s):  
High Performance ◽  
Secondary Ion Mass Spectrometry ◽  
Analytical Sensitivity ◽  
Metaphase Chromosomes ◽  
Banding Patterns ◽  
Sector Mass Spectrometer ◽  
Staining Methods ◽  
The University ◽  
Secondary Ion ◽  
Better Than

We have shown previously that isotope-labelled nucleotides in human metaphase chromosomes can be detected and mapped by imaging secondary ion mass spectrometry (SIMS), using the University of Chicago high resolution scanning ion microprobe (UC SIM). These early studies, conducted with BrdU- and 14C-thymidine-labelled chromosomes via detection of the Br and 28CN- (14C14N-> labelcarrying signals, provided some evidence for the condensation of the label into banding patterns along the chromatids (SIMS bands) reminiscent of the well known Q- and G-bands obtained by conventional staining methods for optical microscopy. The potential of this technique has been greatly enhanced by the recent upgrade of the UC SIM, now coupled to a high performance magnetic sector mass spectrometer in lieu of the previous RF quadrupole mass filter. The high transmission of the new spectrometer improves the SIMS analytical sensitivity of the microprobe better than a hundredfold, overcoming most of the previous imaging limitations resulting from low count statistics.

DESAIN PEMBELAJARAN BAHASA INDONESIA BERBASIS PEMAHAMAN NILAI SIKAP GOTONG ROYONG

2020 ◽  
Vol 13 (2) ◽  
pp. 01-10
Author(s):  
Alpansyah Alpansyah ◽  
Abdul Talib Hasim
Keyword(s):  
Experimental Study ◽  
Language Learning ◽  
Reader Response ◽  
Female Students ◽  
Male Students ◽  
Mutual Cooperation ◽  
Male And Female ◽  
Quasi Experimental ◽  
Bahasa Indonesia ◽  
Better Than

The aims of this study were: (1) to identify an increase in students' understanding of the value of mutual cooperation through the use of reader response rules in Indonesian Language Learning (KRPDPBI); (2) identifying the use of the reader response principle in Indonesian Language learning (KRPDPBI) there are differences between male and female students. The design of this study used a quasi-experimental study with two different methods. The results showed that (1) the achievement of the score of understanding the value of mutual cooperation for students taught by KRPDPBI was better than for students taught by regular learning according to the curriculum; (2) the achievement of the understanding of the value of male students' mutual cooperation is no better than that of female students.

scholarly journals Effect of Gas Diffusion Layer Thickness on the Performance of Anion Exchange Membrane Fuel Cells

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 718
Author(s):  
Van Men Truong ◽  
Ngoc Bich Duong ◽  
Hsiharng Yang
Keyword(s):  
Water Management ◽  
Anion Exchange ◽  
Critical Role ◽  
Gas Diffusion ◽  
Anion Exchange Membrane ◽  
Cell Performance ◽  
Water Flooding ◽  
Diffusion Layer Thickness ◽  
Diffusion Layers ◽  
Exchange Membrane

Gas diffusion layers (GDLs) play a critical role in anion exchange membrane fuel cell (AEMFC) water management. In this work, the effect of GDL thickness on the cell performance of the AEMFC was experimentally investigated. Three GDLs with different thicknesses of 120, 260, and 310 µm (denoted as GDL-120, GDL-260, and GDL-310, respectively) were prepared and tested in a single H2/O2 AEMFC. The experimental results showed that the GDL-260 employed in both anode and cathode electrodes exhibited the best cell performance. There was a small difference in cell performance for GDL-260 and GDL-310, while water flooding was observed in the case of using GDL-120 operated at current densities greater than 1100 mA cm−2. In addition, it was found that the GDL thickness had more sensitivity to the AEMFC performance as used in the anode electrode rather than in the cathode electrode, indicating that water removal at the anode was more challenging than water supply at the cathode. The strategy of water management in the anode should be different from that in the cathode. These findings can provide a further understanding of the role of GDLs in the water management of AEMFCs.

scholarly journals Performance of Seven Consumer Sleep-Tracking Devices Compared with Polysomnography

SLEEP ◽  
2020 ◽  
Author(s):  
Evan D Chinoy ◽  
Joseph A Cuellar ◽  
Kirbie E Huwa ◽  
Jason T Jameson ◽  
Catherine H Watson ◽  
...  
Keyword(s):  
Performance Measures ◽  
Gold Standard ◽  
High Performance ◽  
Sleep Stage ◽  
Sleep Laboratory ◽  
Sleep Assessment ◽  
Sleep Condition ◽  
Different Populations ◽  
Tracking Devices ◽  
Better Than

Abstract Study Objectives Consumer sleep-tracking devices are widely used and becoming more technologically advanced, creating strong interest from researchers and clinicians for their possible use as alternatives to standard actigraphy. We therefore tested the performance of many of the latest consumer sleep-tracking devices, alongside actigraphy, versus the gold-standard sleep assessment technique, polysomnography (PSG). Methods In total, 34 healthy young adults (22 women; 28.1 ± 3.9 years, mean ± SD) were tested on three consecutive nights (including a disrupted sleep condition) in a sleep laboratory with PSG, along with actigraphy (Philips Respironics Actiwatch 2) and a subset of consumer sleep-tracking devices. Altogether, four wearable (Fatigue Science Readiband, Fitbit Alta HR, Garmin Fenix 5S, Garmin Vivosmart 3) and three non-wearable (EarlySense Live, ResMed S+, SleepScore Max) devices were tested. Sleep/wake summary and epoch-by-epoch agreement measures were compared with PSG. Results Most devices (Fatigue Science Readiband, Fitbit Alta HR, EarlySense Live, ResMed S+, SleepScore Max) performed as well as or better than actigraphy on sleep/wake performance measures, while the Garmin devices performed worse. Overall, epoch-by-epoch sensitivity was high (all ≥0.93), specificity was low-to-medium (0.18-0.54), sleep stage comparisons were mixed, and devices tended to perform worse on nights with poorer/disrupted sleep. Conclusions Consumer sleep-tracking devices exhibited high performance in detecting sleep, and most performed equivalent to (or better than) actigraphy in detecting wake. Device sleep stage assessments were inconsistent. Findings indicate that many newer sleep-tracking devices demonstrate promising performance for tracking sleep and wake. Devices should be tested in different populations and settings to further examine their wider validity and utility.

Electrostatic bellow muscle actuators and energy harvesters that stack up

2021 ◽  
Vol 6 (51) ◽  
pp. eaaz5796
Author(s):  
I. D. Sîrbu ◽  
G. Moretti ◽  
G. Bortolotti ◽  
M. Bolignari ◽  
S. Diré ◽  
...  
Keyword(s):  
High Performance ◽  
High Reliability ◽  
Low Cost ◽  
Artificial Muscle ◽  
Pressure Head ◽  
Robotic Systems ◽  
Maximum Pressure ◽  
Term Operation ◽  
Energy Harvesters ◽  
Out Of Plane

Future robotic systems will be pervasive technologies operating autonomously in unknown spaces that are shared with humans. Such complex interactions make it compulsory for them to be lightweight, soft, and efficient in a way to guarantee safety, robustness, and long-term operation. Such a set of qualities can be achieved using soft multipurpose systems that combine, integrate, and commute between conventional electromechanical and fluidic drives, as well as harvest energy during inactive actuation phases for increased energy efficiency. Here, we present an electrostatic actuator made of thin films and liquid dielectrics combined with rigid polymeric stiffening elements to form a circular electrostatic bellow muscle (EBM) unit capable of out-of-plane contraction. These units are easy to manufacture and can be arranged in arrays and stacks, which can be used as a contractile artificial muscle, as a pump for fluid-driven soft robots, or as an energy harvester. As an artificial muscle, EBMs of 20 to 40 millimeters in diameter can exert forces of up to 6 newtons, lift loads over a hundred times their own weight, and reach contractions of over 40% with strain rates over 1200% per second, with a bandwidth over 10 hertz. As a pump driver, these EBMs produce flow rates of up to 0.63 liters per minute and maximum pressure head of 6 kilopascals, whereas as generator, they reach a conversion efficiency close to 20%. The compact shape, low cost, simple assembling procedure, high reliability, and large contractions make the EBM a promising technology for high-performance robotic systems.

scholarly journals A high-fidelity realization of the Euclid code comparison N-body simulation with Abacus

2019 ◽  
Vol 485 (3) ◽  
pp. 3370-3377 ◽  
Author(s):  
Lehman H Garrison ◽  
Daniel J Eisenstein ◽  
Philip A Pinto
Keyword(s):  
Power Spectrum ◽  
High Performance ◽  
High Fidelity ◽  
Step Size ◽  
Time Step ◽  
Code Comparison ◽  
Force Accuracy ◽  
Integration Errors ◽  
Better Than ◽  
Good Agreement

Abstract We present a high-fidelity realization of the cosmological N-body simulation from the Schneider et al. code comparison project. The simulation was performed with our AbacusN-body code, which offers high-force accuracy, high performance, and minimal particle integration errors. The simulation consists of 20483 particles in a $500\ h^{-1}\, \mathrm{Mpc}$ box for a particle mass of $1.2\times 10^9\ h^{-1}\, \mathrm{M}_\odot$ with $10\ h^{-1}\, \mathrm{kpc}$ spline softening. Abacus executed 1052 global time-steps to z = 0 in 107 h on one dual-Xeon, dual-GPU node, for a mean rate of 23 million particles per second per step. We find Abacus is in good agreement with Ramses and Pkdgrav3 and less so with Gadget3. We validate our choice of time-step by halving the step size and find sub-percent differences in the power spectrum and 2PCF at nearly all measured scales, with ${\lt }0.3{{\ \rm per\ cent}}$ errors at $k\lt 10\ \mathrm{Mpc}^{-1}\, h$. On large scales, Abacus reproduces linear theory better than 0.01 per cent. Simulation snapshots are available at http://nbody.rc.fas.harvard.edu/public/S2016.

The Experimental Study on the Inhibition Effect of Fusarium oxyspomm with Bio-Slurry Based on Material Properties

2013 ◽  
Vol 675 ◽  
pp. 317-321
Author(s):  
Meng Ying Fang ◽  
Li Chun Liu ◽  
Fang Yin ◽  
Wu Di Zhang ◽  
Shi Qing Liu ◽  
...  
Keyword(s):  
Experimental Study ◽  
Material Properties ◽  
Water Soluble ◽  
Inhibition Mechanism ◽  
Main Subject ◽  
Soluble Substance ◽  
Inhibition Effect ◽  
Water Soluble Substance ◽  
Main Component ◽  
Better Than

Using petroleum ether to extract the fermentative fluid (bio-slurry), then to get the inhibition mechanism of it, and infer which is the main component in inhibition mechanism of biogas. The conclusion found by the experiment is that fat soluble substance is better than water soluble substance in inhibition mechanism, and fat soluble substance is close to 75% biogas fermentation fluid, while water soluble substance is worst. That is to say, the main subject in inhibition mechanism is hided in the fat soluble substance.

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