Modeling and analysis of passive viscoelastic-legged rimless wheel that generates measurable period of double-limb support

Limit cycle walking including passive-dynamic walkers is generally modeled as a nonlinear hybrid dynamical system with state jumps. The inelastic collision model is usually derived on the assumption that the rear leg leaves the ground immediately after landing of the fore leg. This model is, however, inappropriate in the case of compliant-legged walkers. This paper then reconsiders the traditional collision model and discusses the conditions for transition to double-limb support (DLS) motion, which is not instantaneous through investigations of passive dynamic walking of a viscoelastic-legged rimless wheel. First, we experimentally confirm that measurable period of DLS motion emerges after landing of the fore leg, and develop the corresponding mathematical model. Second, we numerically analyze the fundamental properties of the generated passive-dynamic gaits. Furthermore, we discuss the conditions for transition to DLS motion and specify the computational procedures.     

Fabrication of hollow glass microspheres in the Na2O-B2O3-SiO2 system from metal alkoxides

Hollow glass microspheres (HGS) for laser fusion targets were fabricated in the system Na₂O-B₂O₃-SiO₂ from NaOCH₃, B(OCH₃)₃ and Si(OC₂H₅)₄. Gel powders prepared from metal alkoxides and urea liberate H₂O, CO₂ and NH₃ gases, evolution of which takes place completely at about 500° C. The precursor of HGS is formed by the encapsulation of these gas components in the glass layer formed at the surface of the powder. HGS are produced from the gel powders having both a melting temperature lower than about 1000° C and a viscosity at that temperature lower than 10⁵ P. In the Na₂O-B₂O₃-SiO₂ system, the compositions from which HGS are produced are those containing 55–75 wt% SiO₂ and 0–20 wt% B₂O₃. HGS ranging from 100–500m diameter and 0.5–7.0m wall thickness are obtained by change of urea content.     

快速计算电网可用输电能力的交流灵敏度方法

在电力市场环境下，可用输电能力(ATC)是反映输电设备可用于能量交易的剩余容量的重要指标。ATC一旦确定后，快速估计出系统参数变化对输电能力的影响具有很大的实际应用价值。文中首先基于连续潮流方法，考虑输电支路的过负荷约束、发电机有功及无功出力约束和节点电压约束，计算出ATC的值；然后推导出ATC对多种运行参数摄动的一阶灵敏度计算模型，运行参数包括节点负荷功率、发电节点端电压以及给定的能量交易，这些灵敏度系数能够很快地计算；最后，使用了IEEE30节点系统的算例来验证文中所提出的方法的有效性和快速性。     

Droplet size and morphology analyses of dry liquid

Dry water is a free-flowing powder consisting of numerous solid particle-stabilized water droplets with typical sizes and volumes of 10^?6–10^?4 m and 10^?3–10³ pL, respectively. We describe the first characterization of dry water stabilized with hydrophobic silica nanoparticles, by using laser diffraction droplet size distribution analysis. The water droplet dimensions were measured to be a few tens of micrometers in air, by using the laser diffraction method. These dimensions correspond well with measurements by both laser diffraction and optical microscopy methods for a Pickering-type water-in-n-dodecane emulsion prepared by dispersing dry water in n-dodecane. Optical microscopy confirmed that the dry water consisted of flocs of non-spherical water droplets, and the flocs ranged in size from a few tens of micrometers to a few millimeters in air. On the basis of these results, the flocs of water droplets were proposed to dissociate into individual water droplets under the air blast during droplet size measurement by the laser diffraction method. It was also confirmed that pressurizing the dry water between two glass slides led to encapsulated water leaking from the silica nanoparticle shells. This on-demand pressure-sensitive water leak phenomenon shows a possible usage of the dry waters as a material delivery carrier.     

Large edge magnetism in oxidized few-layer black phosphorus nanomeshes

The formation and control of a room-temperature magnetic order in twodimensional (2D) materials is a challenging quest for the advent of innovative magnetic-and spintronic-based technologies.To date,edge magnetism in 2D materials has been experimentally observed in hydrogen (H)-terminated graphene nanoribbons (GNRs) and graphene nanomeshes (GNMs),but the measured magnetization remains far too small to allow envisioning practical applications.Herein,we report experimental evidences of large room-temperature edge ferromagnetism (FM) obtained from oxygen (O)-terminated zigzag pore edges of few-layer black phosphorus (P) nanomeshes (BPNMs).The magnetization values per unit area are ～100 times larger than those reported for H-terminated GNMs,while the magnetism is absent for H-terminated BPNMs.The magnetization measurements and the first-principles simulations suggest that the origin of such a magnetic order could stem from ferromagnetic spin coupling between edge P with O atoms,resulting in a strong spin localization at the edge valence band,and from uniform oxidation of full pore edges over a large area and interlayer spin interaction.Our findings pave the way for realizing high-efficiency 2D flexible magnetic and spintronic devices without the use of rare magnetic elements.     

Medical image diagnosis of lung cancer by a revised GMDH-type neural network using various kinds of neuron

A revised group method of data handling (GMDH)-type neural network algorithm using various kinds of neuron is applied to the medical image diagnosis of lung cancer. The optimum neural network architecture for medical image diagnosis is automatically organized using a revised GMDH-type neural network algorithm, and the regions of lung cancer are recognized and extracted accurately. In this revised GMDH-type neural network algorithm, polynomial-type and radial basis function (RBF)-type neurons are used for organizing the neural network architecture in order to fit the complexity of the nonlinear system.     

Application of Super High Definition Images in Telemedicine: System Requirements and Technologies for Teleradiology and Telepathology

It was recognized early on that the digitization of medical information would advance the efficiency of diagnostic technology. However, the digitization of image data, which makes up the majority of medical information, is dependent on advances in technologies such as input, processing, transmission, storage, and display. Insufficient advances in such technologies has effectively limited the digitization of image data for medical use. The result of this has been non-networked systems or LANs confined to a single hospital. Such isolated systems integrate only portions of digital medical images such as x-ray computer tomography (CT), magnetic resonance (MR), and computed radiography (CR).Fortunately, recent advances in the areas of super high definition image I/O, high-quality encoding, super high speed transmission, and high-capacity storage has turned the tide in favor of the digitization and networking of all medical information. This paper will focus on the digitization and networking of medical image information used within hospitals and provide a multifaceted study of the technologies necessary for these advances. This will allow us to discuss the present state of related technical developments and the level that has been attained so far. In addition, we have targeted image information that demands the highest level of quality (radiological and pathological images) for application in medical diagnosis using super high definition images, the image technology being developed by the authors of this paper. We will cover the concrete issues and approaches to solutions that must be investigated when building and networking a digital system.     

Protective effect of a vitamin E analog, phosphatidylchromanol, against oxidative hemolysis of human erythrocytes

The protective effect of a vitamin E analog, phosphatidylchromanol [1,2-diacyl-sn-glycero-3-phospho-2′-(hydroxyethyl)-2′, 5′,7′,8′-tetramethyl-6′-hydroxychroman; PCh], against oxidative hemolysis of human erythrocytes was examined and was compared with those of vitamin E (α-tocopherol) and 2,2,5,7,8-pentamethyl-6-chromanol (PMC). These three compounds at 50 μM protected the erythrocytes from hemolysis, when erythrocyte suspension (10%, vol/vol) was incubated with a water-soluble radical generator, 2,2′-azobis(2-amidino-propane)-dihydrochloride (75 mM). When erythrocyte suspension was oxidized after pretreatment with these compounds (50 μM) for 30 min followed by washing, PCh protected about 54% of erythrocytes from the hemolysis, while α-tocopherol protected only about 16% of the cells and PMC did not show any protective effect. During preincubation, α-tocopherol, PMC, and PCh were incorporated into the cells at the concentration of 12.6, 3.7, and 16.3 nmol/mg protein, respectively. Moreover, PCh was found in the ghost membrane fraction at a 20% higher level than α-tocopherol, and no PMC was detected in this fraction. These results indicate that phosphatidyl group in PCh accts as an excellent carrier of chromanol moiety into cells as well as an anchor within membranes more efficiently than phytyl group in α-tocopherol. PMC seems to be slightly anchored within membranes because of the lack of hydrophobic side chain. The excellent antihemolytic activity of PCh is likely to be caused by its accumulation within erythrocyte membranes.