Electrolyte accessibility of non-precious-metal catalysts with different spherical particle sizes under alkaline conditions for oxygen reduction reaction

Fuel cells are one of the most competitive alternative energy sources because their theoretical efficiency is~15%higher than that of internal combustion engines (ICEs) and they are considered cleaner and safer.When fuel cells are used to replace ICEs in cars and energy conversion systems,the system efficiency increases;furthermore,the process becomes more environmentally-friendly because fuel cells produce electricity by using only hydrogen and oxygen,obtained by purifying atmospheric air by filtering out dust and pollutants.Hence,their final product is only water,instead of pollutants like carboFuel cells are one of the most competitive alternative energy sources because their theoretical efficiency is~15%higher than that of internal combustion engines (ICEs) and they are considered cleaner and safer.When fuel cells are used to replace ICEs in cars and energy conversion systems,the system efficiency increases;furthermore,the process becomes more environmentally-friendly because fuel cells produce electricity by using only hydrogen and oxygen,obtained by purifying atmospheric air by filtering out dust and pollutants.Hence,their final product is only water,instead of pollutants like carbon dioxide.n dioxide.

Multi-Modal Data Analysis Based Game Player Experience Modeling Using LSTM-DNN

Game player modeling is a paradigm of computational models to exploit players’behavior and experience using game and player analytics.Player modeling refers to descriptions of players based on frameworks of data derived from the interaction of a player’s behavior within the game as well as the player’s experience with the game.Player behavior focuses on dynamic and static information gathered at the time of gameplay.Player experience concerns the association of the human player during gameplay,which is based on cognitive and affective physiological measurements collected from sensors mounted on the player’s body or in the player’s surroundings.In this paper,player experience modeling is studied based on the board puzzle game“Candy Crush Saga”using cognitive data of players accessed by physiological and peripheral devices.Long Short-Term Memory-based Deep Neural Network(LSTM-DNN)is used to predict players’effective states in terms of valence,arousal,dominance,and liking by employing the concept of transfer learning.Transfer learning focuses on gaining knowledge while solving one problem and using the same knowledge to solve different but related problems.The homogeneous transfer learning approach has not been implemented in the game domain before,and this novel study opens a new research area for the game industry where the main challenge is predicting the significance of innovative games for entertainment and players’engagement.Relevant not only from a player’s point of view,it is also a benchmark study for game developers who have been facing problems of“cold start”for innovative games that strengthen the game industrial economy.

Sample entropy analysis of laser speckle fluctuations to suppress motion artifact on blood flow monitoring

Laser speckle imaging is a common technique to monitor blood flow.The fluctuations in speckle intensity can be related to the blood flow by calculating the speckle contrast,the ratio between the standard deviation of speckle fluctuations and the average intensity.However,this simple statistic calculation is easily affected by motion artifacts.In this study,we applied sample entropy analysis instead of calculating standard deviations of the speckle fluctuations.Similar to the traditional method,sample entropy-based speckle contrast increases linearly with flow rate but was shown to be more immune to sudden movements during an upper arm occlusion test.

Multifunctional Ir–Ru alloy catalysts for reversal-tolerant anodes of polymer electrolyte membrane fuel cells

To address the problem of fuel starvation in fuel-cell electric vehicles,which causes cell voltage reversal and results in cell failure when repeated continuously,we developed a reversal-tolerant anode(RTA) to promote water oxidation in preference to carbon corrosion.Graphitized carbon-supported Ir-Ru alloys with different compositions are employed as RTA catalysts in an acidic polyol solution and are shown to exhibit composition-dependent average crystallite sizes of <5.33 nm.The adopted approach allows the generation of relatively well-dispersed Ir-Ru alloy nanoparticles on the carbon support without severe agglomeration.The activity of IrRu_(2)/C for the hydrogen oxidation reaction is 1.10 times that of the stateof-the-art Pt/C catalyst.Cell reversal testing by simulation of fuel starvation reveals that the durability of IrRu_(2)/C(~7 h) significantly exceeds that of the conventional Pt/C catalyst(~10 min) and is the highest value reported so far.Thus,the developed Ir-Ru alloy catalyst can be used to fabricate practical RTAs and replace Pt catalysts in the anodes of polymer electrolyte membrane fuel cells.

Simultaneous blood flow and oxygenation measurements using an off-the-shelf spectrometer

Blood oxygenation and flow are both important parameters in a living body. In this Letter, we introduce a simple configuration to simultaneously measure blood flow and oxygenation using an off-the-shelf spectrometer. With the integration time of 10 ms, flow phantom measurements, a liquid blood phantom test, and an arm cuff occlusion paradigm were performed to validate the feasibility of the system. We expect this proof-of-concept study would be widely adopted by other researchers for acquiring both blood flow and oxygenation changes due to its straightforward configuration and the possibility of multimodal measurement.

Solution-processable electrode-material embedding in dynamically inscribed nanopatterns(SPEEDIN)for continuous fabrication of durable flexible devices

A facile and scalable lithography-free fabrication technique,named solution-processable electrode-material embedding in dynamically inscribed nanopatterns(SPEEDIN),is developed to produce highly durable electronics.SPEEDIN uniquely utilizes a single continuous flow-line manufacturing process comprised of dynamic nanoinscribing and metal nanoparticle solution coating with selective embedding.Nano-and/or micro-trenches are inscribed into arbitrary polymers,and then an Ag nanoparticle solution is dispersed,soft-baked,doctor-bladed,and hard-baked to embed Ag micro-and nanowire structures into the trenches.Compared to lithographically embossed metal structures,the embedded SPEEDIN architectures can achieve higher durability with comparable optical and electrical properties and are robust and power-efficient even under extreme stresses such as scratching and bending.As one tangible application of SPEEDIN,we demonstrate a flexible metal electrode that can operate at 5 V at temperatures up to 300℃even under the influence of harsh external stimuli.SPEEDIN can be applied to the scalable fabrication of diverse flexible devices that are reliable for heavy-duty operation in harsh environments involving high temperatures,mechanical deformations,and chemical hazards.

New strategy for reversal tolerant anode for automotive polymer electrolyte fuel cell

Since the commercialization of the fuel cell electric vehicles (FCEVs), the polymer electrolyte membrane fuel cell system has been actively improved as a powertrain for ultimate environment-friendly vehicle. During the FCEV operation, various transient conditions such as start-up/shut-down and fuel starvation occur irregularly, which deteriorates the durability of the membrane electrode assembly. In particular, when fuel starvation occurs, the carbon support in the anode is oxidized within few minutes, thus the mitigation of this phenomenon is essential for securing the durability. This short review introduces the concept of reversal tolerant anode (RTA), which is a mitigation method using an oxygen evolution catalyst and reviews some previous reports. In addition, new approach for RTA suggested by authors recently, which is the replacement of Pt anode catalyst by multifunctional IrRu alloy catalyst that simultaneously exhibits the activities for the hydrogen oxidation reaction and the oxygen evolution reaction is introduced.