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171.
Hiroshi Isakari Kazuki Niino Hitoshi Yoshikawa Naoshi Nishimura 《International journal for numerical methods in engineering》2012,90(4):484-505
Preconditioning methods based on Calderon's formulae for the periodic fast multipole method for elastodynamics in 3D are investigated. Three different types of formulations are proposed. The first type is a preconditioning just by appropriately ordering the coefficient matrix without multiplying preconditioners. The other two types utilise preconditioners constructed using matrices needed in the main fast multipole method algorithms. We make several numerical experiments with proposed preconditioners to confirm the efficiency of these proposed methods. We also conclude that the preconditioning of the first type is faster with respect to the computational time than other preconditioning methods discussed in this article. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
172.
Main purpose of this project is to develop fundamental technology for assist robots to recover and maintain human motor skill and to extend scope of human activity. Our goal is to provide a system that adapts to its user’s personal behavior patterns in real-time. We aim to develop a continuous collaboration system between the assist robots and the user where both alternatively adjust to each other to maximize the system’s utility. To understand human movement, we recorded motion sequence of several tasks for different subjects using motion capture system. Through analysis of human motion data, we extracted a general model by rule-based approach. On the other hand, since such tasks are not feasible with static models, we investigate the potential benefit of supervised online learning in the task of online action classi?cation and Deep Learning in the task of acquiring human motion. Finally, developed system was extended to show its potential effect in ergonomics and in assist robotics. 相似文献
173.
M Sakamoto K Saruta Y Nakazawa N Shindo H Maezawa K Yoshikawa M Yoshida K Shiba O Sakai A Saito 《Canadian Metallurgical Quarterly》1996,70(2):116-122
Imaging of anorectal region has drastically changed during the last decade. Transrectal ultrasound and transrectal MRI can be used for staging the rectal tumours. Endoanal sonography can be applied for the classification of perianal fistulae and identification of anal sphincter defects in patients with faecal incontinence. Due to the limitations of endoanal sonography, endoanal MRI was introduced to assess the pathology related to the anal sphincter complex. Endoanal MRI seems superior to endoanal sonography. This paper describes the new developments of the imaging techniques and presents new insights in anatomy and pathology of the anorectum. 相似文献
174.
Y Hayashi K Matsuyama K Takagi H Sugiura K Yoshikawa 《Canadian Metallurgical Quarterly》1995,213(1):317-324
Necdin is a 325 amino acid residue protein localized to the nuclei of postmitotic neurons, which withdraw permanently from the cell cycle. To examine whether necdin confers the postmitotic phenotype, necdin cDNA was stably transfected into NIH3T3 cells, in which the protein was conditionally expressed using a eukaryotic lac repressor-operator expression system. When the transfectants were induced to express ectopic necdin, cell growth was arrested without appreciable reduction in cell viability. The expressed necdin molecule was localized to the nuclei of the transfectants. These results suggest that necdin is a nuclear factor that governs the permanent arrest of cell growth of postmitotic neurons during development of the nervous systems of vertebrates. 相似文献
175.
In recent years an increase in the incidence of esophageal injury due to battery ingestion by infants with miniaturization of batteries has been noted. A case of esophageal ulceration due to lithium battery ingestion is reported. Moreover, an experimental model of esophageal injury due to lithium battery ingestion was produced in dogs, and the tissue damage was evaluated histologically. When the battery was inserted and left in the esophagus for one hour, the structure of the esophagus was well preserved. Minor injury was histologically found in the group in which the battery was retained for two hours. Esophageal injury from the epithelium to the muscle layer was found when the battery was retained for four hours. On the basis of our experimental findings, early extraction within four hours is desirable in the case of an esophageal foreign body of electric battery. 相似文献
176.
T Nagai T Kondo T Sakakibara Y Yoshikawa M Gotoh T Katoh M Kobayashi 《Canadian Metallurgical Quarterly》1997,4(5):484-486
The aim of the present study was to estimate insulin secretion, insulin sensitivity (SI), and glucose effectiveness at basal insulin (SG) in subjects with bulimia nervosa. Eight bulimic patients and eight age-, body mass index-, and sex-matched healthy control subjects without a family history of diabetes were studied. The subjects all had normal glucose tolerance. They underwent a modified frequently sampled intravenous glucose tolerance test; glucose (300 mg/kg body weight) was administered, and insulin (4 mU/kg body weight/min) was infused from 20 to 25 minutes after administration of glucose. SI and SG were estimated by Bergman's minimal model method. Basal insulin (27 +/- 3 v 45 +/- 3 pmol/L) was significantly lower in bulimic patients than in normal controls (P < .05), but basal glucose was similar between the two groups (4.5 +/- 0.1 v 4.9 +/- 0.1 mmol/L, P > .05). The glucose disappearance rate (KG) and acute insulin response to glucose estimated by the intravenous glucose tolerance test (AIR(glucose)) were similar between the two groups (KG, 1.35 +/- 0.29 v 2.20 +/- 0.21 min(-1), P > .05; AIR(glucose), 2,920 +/- 547 v 2,368 +/- 367 pmol/L x min, P > .05). No significant difference was observed in SI between the two groups (1.34 +/- 0.18 v 1.25 +/- 0.20 x 10(-4) x min(-1) x pmol/L(-1), P > .05). On the other hand, glucose effectiveness at basal (SG) and zero (GEZI) insulin was significantly diminished in comparison to normal controls (SG, 0.011 +/- 0.002 v 0.024 +/- 0.002 min(-1), P < .01; GEZI, 0.008 +/- 0.002 v 0.017 +/- 0.003 min(-1), P < .01). Thus, bulimic patients with normal glucose tolerance without a family history of diabetes were characterized by normal insulin secretion, normal SI, and reduced SG and GEZI. 相似文献
177.
PURPOSE: Intraorbital projectile metallic foreign bodies are associated with significant ocular and orbital injuries. The authors sought to evaluate epidemiologic factors, the incidence of associated ocular and orbital injury, and the nature and necessity of surgical intervention in these cases. METHODS: Charts of all patients with projectile intraorbital metallic foreign bodies seen at our institution (27) over the preceding 7 years were evaluated with respect to age, sex, type of injury, associated ocular and orbital injuries, location of the projectile (anterior, epibulbar, or posterior), postinjury visual acuity, and surgical intervention. RESULTS: The majority of patients were male, between the ages of 11 and 30, and had BB pellet injuries. Thirteen projectiles were lodged anteriorly, 4 were in an epibulbar position, and the remaining 10 were posterior to the equator. Twelve of 13 anterior, and 4 of 4 epibulbar foreign bodies were removed surgically, whereas only 2 of 10 posterior foreign bodies required surgery. No case of surgical intervention resulted in a decrease of visual acuity. Associated ocular injuries were both more common and severe in patients with posteriorly located foreign bodies. Final visual acuity was better at presentation and at discharge in patients with anteriorly located foreign bodies. CONCLUSION: Intraorbital projectile metallic foreign bodies can be a source of significant ocular morbidity. Management of these cases is dependent on the location of the projectile. Ancillary radiographic studies can be helpful. Surgery to remove the projectile should be considered in each case, but foreign bodies that are not readily accessible often may be left safely in place. Closer regulation of the pellet gun industry, with an emphasis on education and protective eyewear use, would be helpful in reducing these injuries. 相似文献
178.
K Yoshikawa K Matsuchika S Arihara HC Chang JD Wang 《Canadian Metallurgical Quarterly》1998,46(8):1239-1243
The structural elucidation of six new related polyoxypregnane glycosides, gymnepregosides A (1), B (2), C (3), D (4), E (5) and F (6), together with two known compounds, from the roots of Gymnema alternifolium (Asclepiadaceae) was achieved through on a detailed study of 1H- and 13C-NMR spectral data and chemical means. The results obtained for new compounds, 1-6, show that they are (20S)-pregn-6-ene-3 beta,5 alpha,8 beta,12 beta,14 beta,17 beta,20-heptaol or sarcostin 3-O-glycosides, and all the sugars at C-3 are beta(1-->4)-linked. Some of them possessed benzoyl, cinnamoyl and tigloyl residues as the ester linkages located at C-12 and/or C-20 of the aglycon. 相似文献
179.
Effect of Compositional Variations in the Lead Lanthanum Zirconate Stannate Titanate System on Electrical Properties 总被引:2,自引:0,他引:2
Kelley Markowski Seung-Eek Park Shoko Yoshikawa L. Eric Cross 《Journal of the American Ceramic Society》1996,79(12):3297-3304
The purpose of this work was to evaluate the effect of compositional modifications on the electrical properties of lead lanthanum zirconate stannate titanate (PLZST) ceramics, as well as to examine their electrically induced phasechange behavior. Variations in the Ti:Sn ratio were evaluated. Increased Ti4+ content produced the following: decreased switching field, related to an increased antiferro-electric-ferroelectric (AFE-FE) transition temperature; constant hysteresis (Δ E ) correlated with a constant temperature of the maximum dielectric constant (Tmax ); a sharper dielectric-constant maximum peak; and increased room-temperature dielectric constant ( K ). Variations in the Zr:Sn ratio also were evaluated. Increased Zr4+ content produced the following: increased hysteresis with increased Tmax , decreased maximum dielectric constant, and decreased switching field with increased AFE-FE transition temperature (TAFE _FE ). From these results, with respect to compositional modifications, the AFE-FE switching field (EAFE _FE ) and Δ E were observed to be dependent strongly on TAFE _FE and Tmax , respectively. Negligible change existed in the strain achievable at the switching field, which remained constant for all compositions at ∼0.16%. The significance of this research was the ability demonstrated to tailor the properties of phase-change materials through compositional modifications. 相似文献
180.