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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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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　　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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Stability of long wave length toroidal theta pinch with l=0, l=±1, and l=±2 corrugating magnetic field is investigated with the aid of the sharp boundary-constant pressure model. The stability criterion is obtained for the outward derivative of the specific volume (Remark: Graphics omitted.) with respect to the magnetic field without plasma to be negative on the plasma-vacuum surface. It is also found that the growth rate of the n=0, m=1 mode to vertical and horizontal displacement is different.

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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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Physical analgesia has been used for the treatment of sports injuries. We previously developed a special patch (

patch, BP) that adds pressure to the pain area, demonstrating its analgesic effects in various sports injuries. In this study, we further verified acute and chronic analgesic effects of the BP in 28 subjects (14–44 years of age, 15 males and 13 females) with various pain sites and histories of pain (knee, shoulder, low back, elbow and other joints; 6 months to 3 days). First, the trigger area with muscle induration or tenderness was identified in each subject by palpation, and each subject evaluated the degree of pain using the numerical rating scale (NRS). Then the BPs were applied to completely cover the pain area. The BP treatment was repeated at 2 to 3-day interval until all subjects reported no pain (NRS = 0), and the differences between pre- and post-treatment NRS values were compared for each treatment as the measure of the analgesic effect. Significant analgesic effects were observed in the first and second BP treatments (P = 0.000774 and 0.00149, respectively). The third BP treatment also reduced the pain intensity, but the difference was not statistically significant (P = 0.3734). Some subjects reported mobilization of the pain area after the BP treatment, which was discussed in relation to the potential analgesic mechanism of the BP. These results indicate that the BP has acute and chronic analgesic effects and can be used for the treatment of sports injuries.

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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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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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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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Numerical estimation shows that an upper energy limit of electrons confined in the Nagoya Torus, NBT-1M, exists under electron-cyclotron heating (ECH). This energy limit is determined from the power balance between the microwave input and the losses due to synchrotron radiation and Coulomb drag by bulk electrons, when the maximum harmonic number of ECH corresponding to the energy limit plays an important role. The calculation result of the orbit of the particle reveals us that mirror-trapped electrons can have energies of 10 MeV, while electrons passing through linked mirrors cannot be confined if their energies are above 3 MeV for the magnetic current of 4.2 kA. Successive ECH to a higher harmonic resonance with an injected microwave accelerates electrons, especially mirror-trapped ones, to the energy limit. However, the resonant heating efficiency estimated from the wave damping decreases as the harmonic number n _H increases, and also the total power loss increases as heated electrons become more energetic. The resultant power balance occurs at the electron energy of 4 MeV, to which resonances up to n_H≤ 10 contribute. This numerical result agrees with the observed maximum electron energy of 4 MeV.

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Radial profiles of the plasma space potential are measured in Nagoya Torus (NBT-1) by the use of a heavy ion beam probe. Asymmetric potential profiles owing to toroidal drift are observed in high pressure operation (C-mode). As the pressure is decreased, toroidal plasma is effectively heated (T-mode), poloidal precessional frequency overcomes the electron collision frequency and the equipotential surfaces becomes concentric inside the hot electron ring.

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All-terrain wheelchairs are assumed to be used under such conditions that are on the roads along mountain topography, steep slopes,

roads, muddy roads, etc. It is often used for people with disabilities to enjoy outdoor activities in nature with friends and family. In order to deal with such conditions and usages, all-terrain wheelchairs have different structures and features from normal wheelchairs. In this paper, we focus on the type of all-terrain wheelchair that needs to keep the pitch posture during turning. Here, the pitch posture means the state that the front wheel is lifted. It is hard to keep a stable pitch posture on a steep slope and a road even though the wheelchair is manipulated by an experienced operator. This paper proposes an electric power assist control that keeps this pitch posture stable and reduces the manipulating load of an operator. The most important feature of the control is to control the kinetic energy of the wheelchair, the sum of the energies of longitudinal and pitch motion. This control is implemented on an electrically power assisted wheelchair, and the effectiveness of the control is demonstrated by the experimental results.

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The well-known magnetohydrodynamic equilibrium equations are reduced to the equations of convenient forms for the purpose of an investigation for equilibria of axially asymmetric toroidal plasmas with diffuse boundaries by introducing two scalar functions corresponding to a stream function in an axially symmetric case. In the reductions, it is assumed that the toroidal effect is small; namely the quantities of the configurations are expanded in a ratio of the minor radius to the major radius in toroidal system. Mainly, configurations of type and helical type are considered. In the former case, the forms of the resultant solutions give us a picture of the type configuration which has helical character as the toroidal effect. The helical type configuration in the latter case has no longer completely helically symmetric structures because of its toroidal effect.

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生物の重要な構成成分である蛋白質の機能発現において，蛋白質の立体構造が深く関与している．蛋白質の分子表面形状は，大変複雑な形状を有しており，突起や窪み形状（以下，凹凸形状と称する）を多く含んでいる．蛋白質の機能は，分子表面形状の中でも，特に凹凸部分に強く現れていることがわかっている．そこで本報告では，分子構造データベース（eF-site）に記録されている蛋白質の分子表面情報から局所凹凸形状を抽出して分類する手法，およびその分類結果を探索するための可視化インタフェースを提案する．本手法では，蛋白質分子表面は三角メッシュで近似されていると仮定する．その上でまず，各頂点の接平面と分子表面の交差の有無を求め，これに基づいて局所凹凸を構成する三角形群を抽出する．続いて，各々の局所凹凸形状の特徴量を，軸周りの頂点分布を示したヒストグラムとして算出する．続いて，この特徴量に基づくクラスタリングによって局所凹凸形状を分類する．この分類結果を視覚的に確認するために本手法では，大規模階層型データ可視化手法「平安京ビュー」を応用したインタフェースを提供する．本手法は，複数の蛋白質にわたる分子表面形状の部分類似性の分析に貢献するための，初期検討的な手法の一つと位置づけられる．

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