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Elderly drivers often tend to disobey stop signs, and the number of vehicle accidents associated with this is increasing. The problem we address in this work is that of failure (or inability) of elderly drivers to identify potential conflicts with other road users at stop-sign intersections. The purpose of the study is to investigate the influence of deceleration control with brake hold on the driving habits of elderly drivers in potentially hazardous situations. This study proposes a driver assistance system with three functionalities: 1) information provision to warn drivers that they are approaching a stop-sign intersection; 2) deceleration control to stop the vehicle; and 3) brake hold to ensure that the vehicle has stopped completely. The timeline for a stop-sign intersection scenario is divided into pre- and post-vehicle-stop phases. The effectiveness of the proposed approach in the context of braking-assistance intervention was evaluated by conducting a public-road driving experiment involving 34 elderly drivers. It was observed that the participants could be guided to exhibit rule-following driver behavior voluntarily. The proposed system increased safety for elderly drivers, not only by avoiding stop-sign violations, but also by increasing the available time for a driver to search for hidden hazards in blind spots. We conclude that the braking-assistance intervention system is effective in helping drivers avoid failure or inability to search for potential conflict owing to stop-sign violations.

Isotope effects are one of the most important issues for predicting future reactor operations. Large helical device (LHD) is the presently working largest stellarator/helical device using super conducting helical coils. In LHD, deuterium experiments started in 2017. Extensive studies regarding isotope effects on transport have been carried out. In this paper, the results of isotope effect studies in LHD are reported. The systematic studies were performed adjusting operational parameters and nondimensional parameters. In L mode like normal confinement plasma, where internal and edge transport barriers are not formed, the scaling of global energy confinement time (τ E) with operational parameters shows positive mass dependence (M 0.27; where M is effective ion mass) in electron cyclotron heating plasma and no mass dependence (M 0.0) in neutral beam injection heating plasma. The non-negative ion mass dependence is anti-gyro-Bohm scaling. The role of the turbulence in isotope effects was also found by turbulence measurements and gyrokinetic simulation. Better accessibility to electron and ion internal transport barrier (ITB) plasma is found in deuterium (D) plasma than in hydrogen (H). Gyro kinetic non-linear simulation shows reduced ion heat flux due to the larger generation of zonal flow in deuterium plasma. Peaked carbon density profile plays a prominent role in reducing ion energy transport in ITB plasma. This is evident only in plasma with deuterium ions. New findings on the mixing and non-mixing states of D and H particle transports are reported. In the mixing state, ion particle diffusivities are higher than electron particle diffusivities and D and H ion density profiles are almost identical. In the non-mixing state, ion particle diffusivity is much lower than electron diffusivity. Deuterium and hydrogen ion profiles are clearly different. Different turbulence structures were found in the mixing and non-mixing states suggesting different turbulence modes play a role.

Isotope effects of ECRH plasma in LHD were investigated in detail. A clear difference of transport and turbulence characteristics in H and D plasmas was found in the core region, with normalized radius ρ < 0.8 in high collisionality regime. On the other hand, differences of transport and turbulence were relatively small in low collisionality regime. Power balance analysis and neoclassical calculation showed a reduction of the anomalous contribution to electron and ion transport in D plasma compared with H plasma in the high collisionality regime. In core region, density modulation experiments also showed more reduced particle diffusion in D plasma than in H plasma, in the high collisionality regime. Ion scale turbulence was clearly reduced at ρ < 0.8 in high collisionality regime in D plasma compared with H plasma. The gyrokinetic linear analyses showed that the dominant instability ρ = 0.5 and 0.8 were ion temperature gradient mode (ITG). The linear growth rate of ITG was reduced in D plasma than in H plasma in high collisionality regime. This is due to the lower normalized ITG and density gradient. More hollowed density profile in D plasma is likely to be the key control parameter. Present analyses suggest that anomalous process play a role to make hollower density profiles in D plasma rather than neoclassical process. Electron scale turbulence were also investigated from the measurements and linear gyrokinetic simulations.

Collision dynamics of opposing unsteady supersonic jets injected in background gas with shock waves were calculated to simulate double pulsed laser ablation. Since the jets are deflected by collision and the motion of debris is ballistic. This characteristic can be used to reduce the number of debris when shields are mounted in front of substrate. The flow of jets through installed shields is complicated by the interaction between shields and jets, and between shields and shock waves. We investigate influence of shield position on the shock waves and the jets by numerical calculations. Axisymmetric two-dimensional compressible Euler equations were solved using the finite volume method by using ANSYS Fluent 14.0.0 code. The shields with slit was mounted parallel to the direction of initially injected jets. In order to investigate the influence of shield position on the shock waves and the jets, the shield position and background gas pressure were adopted as parameters. The jets and shock wave are deflected by collision and they can pass through the slit of shields. The passed shock wave reflects at the substrate mounted behind the slits and it forces back the jet to decrease the jet velocity. The shield position governs the velocity and amount of the jet that reach the substrate.

Multi-species impurity seeding is an advanced operation scenario to mitigate the divertor heat load for the realization of future fusion reactors. In the large helical device, divertor detachment is successfully sustained using higher-Z (krypton, Kr) and lower-Z (neon, Ne) superimposed seeding. Emission from Kr impurities is drastically enhanced if it is followed by Ne seeding. Plasma radiation can be enhanced even at the upstream region in the edge plasma compared with Ne only seeded plasmas with suppression of impurity accumulation toward the central plasma. The characteristics of divertor heat load reduction and energy confinement are comparable between the Kr + Ne seeding and Ne only seeding under the same radiation fraction. However, while the detachment in Ne only seeding is transient, the detachment in Kr + Ne seeding is stable. It indicates that multi-species impurity seeding can be competitive for steady-state operation although further investigation is desired about the balance between divertor heat load reduction, impurity screening, and confinement degradation. The Kr emission enhancement is strongly affected by electron density and temperature at the last closed flux surface resulting in impurity penetration.

Effects of head on collision on two laser ablation plumes in background gas are revealed by observation of plume expansion dynamics. Nb2O5 and Ni targets were set parallel to each other and irradiated simultaneously by two YAG lasers in He gas under various gas pressures. The plume expansion dynamics was monitored by a gated ICCD camera. The plumes stagnate at 500 Pa after collision of two plumes. The backward movements of the plumes are observed above 2000 Pa, even though the plumes do not collide with each other. We estimated propagation of shock front by point blast model and the results indicate that the backward movement at high background gas pressure is due to the collision between plume and shock front. These results indicate that collision with counter shock wave is very important for plume expansion dynamics.

Describing business processes by directed graphs is a common way for system designers, because it makes easier to realize how the process goes on. However the concept of serviceoriented architecture increased difficulty of the business process management system development, because the specification of the whole system and each software unit are different in general. Therefore, describing behavioral model for each software units is required. A flow of interaction of software unit is called a scenario. In our previous study, we showed the algorithm to synthesize model of each software unit when specification of whole system is given by one scenario. In this paper, we show conditions to synthesize models when the whole system has two scenarios. We also apply the conditions to a simple business process.

Positive isotope effects have been found in electron cyclotron resonant heating plasma of the Large Helical Device (LHD). The global energy confinement time (τE) in deuterium (D) plasma is 16% better than in hydrogen (H) plasma for the same line-averaged density and absorption power. The power balance analyses showed a clear reduction in ion energy transport, while electron energy transport does not change dramatically. The global particle confinement time (τp) is degraded in D plasma; τp in D plasma is 20% worse than in H plasma for the same line-averaged density and absorption power. The difference in the density profile was not due to the neutral or impurity sources, but rather was due to the difference in the transport. Ion scale turbulence levels show isotope effects. The core turbulence (ρ = 0.5–0.8) level is higher in D plasma than in H plasma in the low collisionality regime and is lower in D plasma than in H plasma. The density gradient and collisionality play a role in the core turbulence level.

The electrochemical copolymerization of pyrrole and 1-(2-carboxyethyl)pyrrole (Py-COOH) was carried out, and a conducting polymer film with a Py-COOH content of 5% and a conductivity of 6.6 × 10−4 S/cm was obtained. Alcohol dehydrogenase (ADH) was attached through amide linkage onto the surface of the conducting polymer film for the purpose of fabricating an ADH-immobilized electrode applicable to the amperometric sensing of ethanol. The quantity and activity of the immobilized ADH were determined to be 400 μg/cm2 and 0.6 U/mg, respectively. With the ADH-immobilized electrode, amperometric ethanol sensing was attempted in the presence of nicotinamide adenine dinucleotide (a cofactor of ADH) and Meldola's blue (an electron-transferring mediator). The ADH-immobilized electrode made the current response correspond to ethanol concentration, which reached 10 μA/cm2 at a concentration of 14 mM. The selectivity of the sensing was examined with alcohols other than ethanol. It was found that the ADH/copolymer electrode had a considerably larger current response to allyl alcohol. The selectivity was attributed to the specificity of native ADH with respect to the oxidation of alcohols. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010