This paper deals with analysis of worst-case L₂ gain in terms of responses due to disturbance for systems with controller switching. Control systems often have responses caused by switching controllers. Those responses are harmful, since they not only degrade control performance but also may damage plants, actuators and so on. Several methods have been proposed to attenuate responses. However, most of those methods lack performance and/or robustness guarantee against disturbance and/or uncertainty. In particular, no exact definitions of responses have been formulated. This paper first defines responses to be dealt with. Based on the definition, we propose a method to analyze the responses by using LMIs. The method can be applied to the worst-case Hankel norm analysis. The effectiveness of the proposed method is examined by using a numerical example.

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This paper deals with analysis of responses for systems with switching and uncertainty. Switching in control systems often causes responses. Since those responses are harmful, several methods have been proposed to attain bumpless transfer. However, the existing methods may not have enough robustness. Recently, another method has been proposed to analyze responses for systems with uncertainty, where the responses are analyzed through the worst-case L2 gain from the past disturbance to the future control output, with the expense of conservatism. This paper aims to improve the results by reducing the conservatism. The proposed analysis results are less conservative and given in terms of linear matrix inequalities. A numerical example shows that the proposed method actually gives a less conservative result than existing methods.

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This paper deals with analysis of the worst-case response due to disturbances for systems with switching and uncertainty. responses are often caused by switching in control systems. Since those responses are harmful, several methods of bumpless transfer have been proposed. However, most of the existing results do not deal with robustness. Recently, a method has been proposed to analyze the worst-case gain from past disturbance to future output based on LMIs. Although that result guarantees robustness, it may not be suitable for further applications to e.g. synthesis problems since the result lacks duality. This paper proposes a method to analyze the worst-case L₂ gain from past disturbances to future controlled output based on linear matrix inequalities. The condition given in this paper has symmetry in terms of duality. Moreover, a numerical example shows that the proposed method gives a less conservative result than existing methods.

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Background: The arrhythmogenic role of complex atrial morphology has not yet been clearly elucidated. We hypothesized that

tissue geometry can induce action potential duration (APD) dispersion and wavebreak in atrial fibrillation (AF).

Methods and Results: We simulated a 2D-

atrial model by varying the degree of bumpiness, and 3D-left atrial (LA) models integrated by LA computed tomographic (CT) images taken from 14 patients with persistent AF. We also analyzed wave-dynamic parameters with bipolar electrograms during AF and compared them with LA-CT geometry in 30 patients with persistent AF. In the 2D- model, APD dispersion increased (P<0.001) and wavebreak occurred spontaneously when the surface bumpiness was greater, showing phase transition-like behavior (P<0.001). The bumpiness gradient 2D-model showed that spiral wave drifted in the direction of higher bumpiness, and phase singularity (PS) points were mostly located in areas with higher bumpiness. In the 3D-LA model, PS density was higher in the LA appendage (LAA) compared with other parts of the LA (P<0.05). In 30 persistent-AF patients, the surface bumpiness of LAA was 5.8-fold that of other LA parts (P<0.001), and exceeded critical bumpiness to induce wavebreak. Wave dynamics complexity parameters were consistently dominant in the LAA (P<0.001).

Conclusions:

tissue geometry promoted APD dispersion, wavebreak, and spiral wave drift in in-silico human atrial tissue, and corresponded to clinical electroanatomical maps.

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A computational study of resistive drift waves in the edge plasma of a torus is presented. The magnetohydrodynamic equilibrium is obtained from a three-dimensional local equilibrium model. The use of a local magnetohydrodynamic equilibrium model allows for a computationally-efficient systematic study of the impact of the magnetic field structure on drift wave stability.

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Based on the ideal observer analysis, we investigated sampling properties of image information used by human visual system, for symmetrical pattern discrimination on 3D surface. There were three models of ideal observer (IO) to perform the task: 2D-IO using 2D projection image (i.e., retinal image), 2.5D-IO using image transformed to canonical view, and 3D-JO using recovered pattern image of 2D plane. We measured discrimination thresholds on the task for each IO model and subjects, and calculated human statistical efficiency relative to each ideal observer. The results indicated for the detection of a diagonal symmetry in the surface that human performance was similar to 3D-IO. This implies that human observers use the structure of the surface to detect the diagonal symmetry.

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Speed bumps and rumble strips have been introduced into the traffic infrastructure to improve traffic safety. When a vehicle travels on a road where speed bumps and rumble strips are installed, vibration stimuli are transmitted to the driver to encourage control of the speed and position of the vehicle. In this letter, speed bumps are applied to an automated driving system. More precisely, this letter considers the speed control of a mobile robot using vibration stimuli from

road surfaces. We formulated a design problem for a speed control law for a mobile robot and proposed a controller that can adjust the speed according to road surface geometry. The performance of the proposed method was verified via simulation using Unity.

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This research aims to develop a method to learn a walking policy for multi-legged robots in various rough terrain. For this purpose, this paper investigates the generalization property of a learned walking policy in rough terrain. Using this result, we expect to provide a method to reduce the number of walking policies with which the robot can walk through any variations of terrain.

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The tactile sensations of leather car seat covers with different grain patterns were evaluated by physical touch. The covers′ physical properties were also measured. The tactile sensations were evaluated using adjectives like “high-class” and “smoothness” which were examined using principal component analysis. From the correlations between physical properties and sensory evaluations, it was found that tactile sensations correlate with the physical properties of compression and surface friction. The tactile sensations of leather covers were influenced by the grain leather pattern, and those sensations could be predicted by the physical properties. These results will contribute to a final seat design.

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We propose a Mars aerial exploration mission using a micro Mars airplane released from CubeSat. In this paper, the airplane is designed, and its feasibility is evaluated in terms of maximum flight Mach number and wing structure mass. The airplane is small enough to be stored in 1U (a cube of 10cm) and has a total mass of 950g. A glider type is suitable considering the severe constraints of size and mass. The airplane also requires a relatively large wing to fly through the thin Martian atmosphere. Therefore, we adopt an inflatable wing to develop a compact and large wing. The cross-section of the wing is

airfoil due to the multiple pressurized tubes that extend in the spanwise direction. Aerodynamic measurements are conducted in a wind tunnel to study the aerodynamic characteristics of the wing. Finally, the specifications of the airplane are proposed based on the wind tunnel tests results. The proposed airplane with its wingspan of 0.9m is capable of gliding over 40km in nine minutes.

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Silver (Ag) plating films on Cu alloys are widely used in various electronic and electrical devices due to their excellent electrical conductivity advantageous over other metals, which is advantageous over other metals. In recent years, with the rapid development of HEVs and EVs, the demand for connectors and power devices for high–voltage applications is increasing, and it is expected that highly electrical/thermal conductive silver–plating films with various thicknesses will be essential in the future. In this study, Ag–Graphene composite plating films with high thermal and electrical conductivities were fabricated with the thickness ranging from 5 to 60 µm in

– and smooth–type, and the effects of film thickness and surface morphology on various properties were investigated. Compared with pure silver–plated films, the particles on the composite films increased with the increase of the film thickness, which is caused by the accumulation of micro–particles with graphene sheets. The –type composite films exhibited high thermal conductivities of 414–451 W/m K for 40–60 µm thick films using laser flash method, which is around 5 times higher than that of pure Ag films with same thickness. The excellent thermal conductivity can be attributed to the synergistic effect of graphene component with the highest thermal conductivity and the large surface area of the films, with the latter playing a more important role than the former. The same effect was also confirmed in cyanide composite plating films used in industrialization. Therefore, Ag–Graphene composite films are expected to be promising plating materials for power devices and charging connectors due to their controllable surface morphology and high electrical/thermal conductivity.

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Multiple endocrine neoplasia type 2B (MEN2B) is an extremely rare disease, most often caused by a de novo p.Met918Thr RET mutation. Medullary thyroid carcinoma of MEN2B has a good prognosis if diagnosed by one year of age. However, diagnosis of MEN2B within the first year of life is markedly challenging owing to its high de novo occurrence and lack of clarity in terms of extra-endocrine symptoms that could aid early diagnosis. Herein, we present six cases of Japanese children with MEN2B harboring the p.Met918Thr RET variant. Exploratory data extraction was conducted using a questionnaire. The patients underwent thyroidectomy at a median age of 11 yr (range, 6–19 yr). Four of the six patients underwent neonatal hospitalization at birth without complications, and three tested positive for neuroblastoma screening at infancy. The patients presented at least one MEN2B-associated symptom before one year of age, including ganglioneuromas, pseudo-Hirschsprung disease, alacrima,

lips, sucking disability, or decreased muscle tone, along with other suspected comorbidities, such as Williams or Prader–Willi syndrome. This case series demonstrates that MEN2B manifests through several extra-endocrine symptoms by the age of one year.

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The impact of output voltage waveform variations on the induced flow velocity and driving efficiency of plasma actuators (PAs) was investigated by measuring the velocity distribution, power consumption, and thrust. When PAs were driven using a simple power supply unit with a semiconductor power device, the capacitance of the PA varied with noted differences in the total spanwise overlapped electrode length (L_s) at which dielectric barrier discharge occurred, affecting the induction flow efficiency based on the applied voltage waveform. For a PA with 100 mm spanwise overlapped electrodes, the output voltage waveform could be adjusted from a “

” to a “sinusoidal” form by incorporating a variable reactor. This reactor modified the impedance on the secondary side of the power supply circuit by adjusting the air gap (d_f) of the EI core, which regulates inductance. Applying a sinusoidal voltage waveform is preferable for efficient PA operation in cases in which a power supply is used in conjunction with a simple electrical circuit. However, even when a slightly distorted waveform was used, such as a “quasi-sine wave,” instead of a pure sinusoidal voltage, the drive efficiency remained largely unaffected. In contrast, waveforms with high-voltage gradients near zero crossings such as “wavy” and “” led to reduced efficiency.

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The characteristics of the waves in the ion-cyclotron range of frequency (ICRF) in a torus having a strong non-uniform magnetic field both in the toroidal and the radial directions are investigated experimentally. Several effects of the strong non-uniformity on propagation, damping and radial profile of the ion cyclotron wave are observed; the split of the dispersion curves for m=0, ±1 modes, the wave damping depending on the modes m and on the frequency even below the cyclotron frequency and the peaking of the poloidal component of the wave field slightly inside the cyclotron resonance layer. These strong non-uniform characteristics are compared with the two-dimensional wave field calculation using the finite-element method.

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Maximum-J (J is the second adiabatic invariant) capability, i.e., drift reversai capability, is examined in a quasi-poloidally symmetric steliarator as a possible mechanism for turbulent transport suppression. The radial variation of the uniform magnetic field component plays a crucial role for the drift reversal in a quasi-poloidally symmetric configuration.

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　　In the over 10-year follow-up of 57 cases of primary cranial expansion with distraction by our team, 2 cases have resulted in a

calvarial deformity. These cases are reported in detail.
　　Case 1 was a 3-year-old patient diagnosed with oxycephaly who underwent calvarial expansion. The post-operative course was uneventful. Since puberty, the cranium began to gradually deform unevenly, requiring contouring surgery 15 years later. CT imaging revealed a wave-shaped outer cortex, and the bone marrow was fatty and yellowish in some areas.
　　Case 2 was mild trigonocephaly with increased intra-cranial pressure. Frontal advancement was successfully carried out by distraction when the patient was 2 years of age. After six years, a marked skull deformity in the front of the coronal suture was noted. Wavy cortical bone was also observed by X-ray.
　　The deformity on the distracted cranium may have been caused by overreaction during adolescence, mainly in the medulla of the frontal bone, where endochondral ossification occurs at the edge and film ossification occurs at the center. As such, the coronal ring area must be carefully followed-up for a long time after distraction surgery.

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Characteristics of spontaneous transition to a high confinement mode (H-mode) have been studied in a helical-axis heliotron device, Heliotron J. The radiation profile measured with a silicon photodiode array shows that a interesting change in the profile occurs at the plasma edge region in the transition phase, forming a strong gradient near the last closed flux surface (LCFS). Relating to the transition, characteristics of bursty density and particle-flux fluctuations current in the scrape off layer (SOL) have been investigated. The probability distribution function for the fluctuations has a tail structure in the L-mode phase, while the tail is suppressed and its direction is reversed after the transition, which may be related to the suppression of edge-plasma turbulence.

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Vibration specific ride comfort of a vehicle on an urban street was evaluated by the psychological response of test subjects with the use of adjectives, while adjusting damping force of the damper. The test results indicate the vibration specific ride comfort can be measured by the psychological response of a passenger. The vibration specific ride comfort can be defined by a feeling of luxuriousness, feeling of being heaved, and feeling of being jabbed. Also, the vibration specific ride comfort is impaired by a feeling caused by the vibration coming from stiffened dampers.

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A new series of anion-exchange extractants, polymethylenebis[3-(N, N-dioctylcarbamoyl)pyridinium]s (abbreviated as C_nBPy; n=3, 4, 6, 8, 10) were synthesized; they are lipophilic dipyridinium ions bearing two cationic centers at various separations within a molecule. The extraction behavior of metal ions from aqueous hydrohalic acid was investigated. The extractability of divalent metal ions (zinc(II) and cadmium(II)) decreased in the order: C_10->C_8- >C_6->C_4->C₃BPy> monocationic extractant (1-butyl-3-(N, N-dioctylcarbamoyl)pyridinium, abbreviated as ). However, in the extraction of trivalent metal ions ( iron(III) and indium(III)), the extraction ability of extractants decreased in the order: _??_C_10->C_8->C_6->C_4->C₃BPy. These orders were analogous to those observed in the previously reported extractions using diphosphonium extractants. The extraction of organic dianionic substrates, 1, 5- and 2, 6-naphthalenedisulfonates (abbreviated as NDS^2-) was also investigated. The extraction of 1, 5-NDS^2- decreased in the order: C₁₀_??_C_8-_??_C_6->C_4->C₃BPy, while that of 2, 6-NDS^2-decreased in the order: C_10- >C_8->C_6->C_4->C₃BPy. There were no distinct maxima in the plot of extraction constant (log K_ex) vs. n-value; such behavior was considerably different from that of diphosphonium extractants reported previously. The structural aspects of extractants and their relation to extraction selectivity are discussed.

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