Simulation of postoperative 3D facial morphology using a physics-based head model

We propose a prototype of a facial surgery simulation system for surgical planning and the prediction of facial deformation. We use a physics-based human head model. Our head model has a 3D hierarchical structure that consists of soft tissue and the skull, constructed from the exact 3D CT patient data. Anatomic points measured on X-ray images from both frontal and side views are used to fire the model to the patient's head. The purposes of this research is to analyze the relationship between changes of mandibular position and facial morphology after orthognathic surgery, and to simulate the exact postoperative 3D facial shape. In the experiment, we used our model to predict the facial shape after surgery for patients with mandibular prognathism. Comparing the simulation results and the actual facial images after the surgery shows that the proposed method is practical.     

Hand shape classification in various pronation angles using a wearable wrist contour sensor

Hand gestures are potentially useful for communications between humans and between a human and a machine. However, existing methods entail several problems for practical use. We have proposed an approach to hand shape recognition based on wrist contour measurement. Especially in this paper, two assignments are addressed. First is the development of a new sensing device in which all elements are installed in a wrist-watch-type device. Second is the development of a new hand shape classifier that can accommodate pronation angle changes. The developed sensing device enables wrist contour data collection under conditions in which the pronation angle varies. The classifier recognizes the hand shape based on statistics produced through data forming and statistics conversion processes. The most important result is that no large difference exists between classification rates that include or those that exclude the independent (preliminary) pronation estimation process using inertia measurement units. This result shows two possible insights: (1) the wrist contour has some features that depend on the hand shape but which do not depend on the pronation angle, or (2) the wrist contour potentially includes pronation angle variation information. These insights indicate the possibility that hand shape can be recognized solely from the wrist contour, even while changing the pronation angle.     

Crystallization of potassium titanate from the amorphous phase

By using amorphous potassium titanates as the starting materials, a sintered body of K₂Ti₄O₉ or K₂Ti₆O₁₃ with porous and fibrous textures was prepared. K₂Ti₂O₅ and a new phase, K₆Ti₄O₁₁ were synthesized by the thermal reaction of KNO₃ with TiO₂ at 1000° C for 10 to 20 h. On leaching in water to expel excess of potassium ions, both phases became amorphous. After mixing and moulding these amorphous materials in the desired proportion, a sintered body containing fibrous crystals of K₂Ti₄O₉ was readily fabricated by heating at 1000° C for 12 h. When 5 wt % B₂O₃ was added to the amorphous phases, single phase K₂Ti₆O₁₃, with a fibrous texture grew well on heating at 1000° C for 12 h. Addition of PVA polymer to the amorphous phases was responsible for controlling the porosity of the sintered body, e.g. about 52% theoretical density at 20 wt% PVA polymer. The optimum conditions for preparing the amorphous phases were systematically examined and the effect of the chemical reaction environments, such as different crucible materials on the calcination of KNO₃ and TiO₂ were also discussed.     

Repetition bend properties of Cu-Cr and Cu-Cr-Sn alloys

Repetition numbers of bending of Cu-0.81 wt% Cr, Cu-0.81 wt% Cr-0.14 wt% Sn and Cu-0.26 wt% Cr-0.10 wt% Sn alloys were investigated. After solution treatment, the first two types of copper alloys have a primary chromium phase; this is not so in the last alloy. The primary chromium phase does not influence the repetition numbers of bending of cold-rolled specimens; the repetition numbers of bending of specimens aged at 723 K for 1.8 × 10³ sec after cold rolling are higher than those of cold-rolled specimens. The cause of this is considered to be a recovery of work-hardening during ageing.     

TEM,XPS and SIMS Analyzes on Grain Boundary of Lanthanum Chromites

The morphological characteristics, chromium valence state, and cation transport in the vicinity of grain boundary in La_1-xCa_xCrO₃ were investigated by using TEM/EDS, XPS and SIMS techniques. The width of grain boundary was around 1 nm where anomalous enrichment of calcium was observed. Higher valence state of chromium such as Cr⁶⁺(d⁰) was detected in the grain boundaries whereas Cr³⁺(d³) and Cr⁴⁺(d²) were dominant in the bulk. Very fast interdiffusion of alkaline earths was observed in the Sr²⁺-La_0.75Ca_0.25CrO₃ system. All observed phenomena were correlated by assuming the A-site vacancy which may be induced by the formation of Cr⁶⁺ at grain boundaries.     

Densification of magnesia-based inert matrix fuels using asbestos waste-derived materials as a sintering additive

A new concept for densification of minor actinide-containing inert matrix fuels (IMFs) using asbestos waste-derived materials was proposed for the effective utilization of resources and health protection of the general public. In this concept, magnesium silicates, which are mainly generated by the decomposition of asbestos in low temperature heat-treatments, are used as a sintering additive to achieve high density magnesia (MgO) -based IMFs at relatively low sintering temperature. In the present study, preliminary fabrication tests of MgO-based IMFs with magnesium silicates were carried out using cerium oxide (CeO₂) as a representative of minor actinide oxides. The sintered densities of MgO-based IMFs increased with use of the additives. The sintering behavior of MgO-based IMFs with magnesium silicate additives was discussed from the viewpoints of the effects of magnesium silicates on the densification of the MgO and CeO₂.     

Ionization probability of secondary ions sputtered from Si(1 1 1) and Ge(1 1 1) surfaces

We have measured the energy distributions of the secondary ions sputtered from the Si(1 1 1) and Ge(1 1 1) surfaces and investigated the ionization probabilities of sputtered Si⁺ and Ge⁺ ions for clarifying their ionization mechanisms. The observed ionization probabilities depend on the velocity of Si⁺ and Ge⁺ ions. This velocity dependence can be successfully analyzed by a theoretical expression, which was proposed originally for the metal surfaces. This implies that the ionization mechanism of Si⁺ and Ge⁺ ions is the same as ions sputtered from the metal surface, i.e., the resonant electron transfer in the high velocity regime and the thermal excitation process in the low velocity regime. The difference in the ionization probability between Si⁺ and Ge⁺ ions is well explained by the difference in the band gap energy.     

Debye Temperature and Electrical Conduction of Fe2O3-CaO-SiO2 Glasses

The electrical conductivity of iron-containing silica glasses was measured from 80 to 350 K. The conductivity data were analyzed based on the hopping conduction theory. The hopping binding energy (W_p) and disorder energy W_D) were calculated from the activation energy at high and low temperatures. The disorder energy obtained was much lower than reported for FeO-P₂O₅ glasses, but similar to that for vandium-containing glasses.