Ultrafast single-channel machine vision based on neuro-inspired photonic computing

High-speed machine vision is increasing its importance in both scientific and technological applications. Neuro-inspired photonic computing is a promising approach to speed-up machine vision processing with ultralow latency. However, the processing rate is fundamentally limited by the low frame rate of image sensors, typically operating at tens of hertz. Here, we propose an image-sensor-free machine vision framework, which optically processes real-world visual information with only a single input channel, based on a random temporal encoding technique. This approach allows for compressive acquisitions of visual information with a single channel at gigahertz rates, outperforming conventional approaches, and enables its direct photonic processing using a photonic reservoir computer in a time domain. We experimentally demonstrate that the proposed approach is capable of high-speed image recognition and anomaly detection, and furthermore, it can be used for high-speed imaging. The proposed approach is multipurpose and can be extended for a wide range of applications, including tracking, controlling, and capturing sub-nanosecond phenomena.Comment: 30 pages, 12 figure

Petrology of Abyssal Peridotites in Diverse Tectonic Settings : Generalities and Differences in Mantle Melting, Melt Extraction and Post-melting Proesses, and Significance of Small-scale Variations

金沢大学大学院自然科学研究科Promoting Environmental Pesearch in Pan-Japan Sea Area : Young Researchers\u27 Network, Schedule: March 8-10,2006,Kanazawa Excel Hotel Tokyu, Japan, Organized by: Kanazawa University 21st-Century COE Program, Environmental Monitoring and Prediction of Long- & Short- Term Dynamics of Pan-Japan Sea Area ; IICRC(Ishikawa International Cooperation Research Centre), Sponsors : Japan Sea Research ; UNU-IAS(United Nations University Institute of Advanced Studies)+Ishikawa Prefecture Government ; City of Kanazaw

Trace element compositions of jadeite (+omphacite) in jadeitites from the Itoigawa-Ohmi district, Japan: Implications for fluid processes in subduction zones

金沢大学理工研究域自然システム学系Trace-element compositions of jadeite (±omphacite) in jadeitites from the Itoigawa-Ohmi district of Japan, analyzed by a laser-ablation inductively coupled plasma mass spectrometry technique showed chemical zoning within individual grains and variations within each sample and between different samples. Primitive mantle-normalized patterns of jadeite in the samples generally showed high large-ion lithophile element contents, high light rare earth element/heavy rare earth element ratios and positive anomalies of high field strength elements. The studied jadeitites have no signatures of the protolith texture or mineralogy. Shapes and distributions of minerals coupled with chemical zoning within grains suggest that the jadeitites were formed by direct precipitation of minerals from aqueous fluids or complete metasomatic modification of the precursor rocks by fluids. In either case, the geochemical characteristics of jadeite are highly affected by fluids enriched in both large-ion lithophile elements and high field strength elements. The specific fluids responsible for the formation of jadeitites are related to serpentinization by slab-derived fluids in subduction zones. This process is followed by dissolving high field strength elements in the subducting crust as the fluids continue to circulate into the subducting crusts and serpentinized peridotites. The fluids have variations in chemical compositions corresponding to various degrees of water-rock interactions. © 2007 The Authors; Journal compilation © 2007 Blackwell Publishing Asia Pty Ltd

Evaluation of the relationship between joint torque and angular velocity using a modified leg extension machine

OBJECTIVE: When performing knee extension using a leg extension machine, the lower limb is pushed back in the direction in which knee flexion occurs in response to the freefall of the weight after maximal knee extension. Therefore, eccentric contractions of the knee extensors are needed, which may lead to cumulative fatigue of the extensors, consequently reducing the reliability of the knee extensor torque values. This study aimed to determine the relationship between joint torque and angular velocity in one repetition maximum (1RM) measurement for knee extension using a leg extension machine with and without a modification to prevent counter-rotation. METHODS: Twenty-one healthy adult men (mean age: 27.7±5.4 years) participated in the study. A leg extension machine was modified to prevent counter-rotation due to the freefall of weights. The subjects performed knee extension using the modified leg extension machine, and the joint torque and angular velocity were calculated using two-dimensional analysis. A regression equation between these two factors was created to estimate the maximal isometric torque. RESULTS: Both the joint torque and angular velocity tended to increase after modification of the leg extension machine, although these differences were not significant. Similarly, there were no significant post-modification changes in the estimated maximal isometric torque. CONCLUSIONS: Our results showed that the joint torque, angular velocity, and estimated maximal isometric torque remained unchanged after machine modification; thus, the modified leg extension machine may make it possible to produce the knee extensor torque more safely in 1RM measurement

Factors Associated with Inadequate Tissue Yield in EUS-FNA for Gastric SMT

Aims. Our aim was to identify the factors that made the specimens inadequate and nondiagnostic in endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsy of suspected submucosal tumors (SMTs). Methods. From August 2001 to October 2009, 47 consecutive patients with subepithelial hypoechoic tumors originating in the fourth sonographic layer of the gastric wall suspected as GIST by standard EUS in Chiba University hospital underwent EUS-FNA for histologic diagnosis. We evaluated patient age, sex, location of lesion, size, pattern of growth in a stomach, and pattern of echography retrospectively. We defined a case of gaining no material or an insufficient material for immunohistological diagnosis as nondiagnostic. Results. The diagnostic yield of EUS-FNA for the diagnosis of gastric SMTs was 74.5%. Multivariate logistic regression analysis identified that age of under 60 years (compared with patients older than 60 years: odds ratio [OR] = 11.91, 95% confidence interval [CI] = 1.761–80.48) and location of SMT at lower third area (compared with upper or middle third area: OR = 10.62, 95% CI = 1.290–87.42) were the predictive factors for inadequate tissue yield in EUS-FNA. Conclusions. The factors associated with inadequate tissue yield in EUS-FNA were younger age and the location of lesion at lower third area in stomach

Origin of Spinal-Pyroxene Symplectite in Lherzolite Xenoliths from Tallante, Southeast Spain : Envidence for Mantle Diapirism beneath the betic-Rif Zone

金沢大学大学院自然科学研究科Promoting Environmental Pesearch in Pan-Japan Sea Area : Young Researchers\u27 Network, Schedule: March 8-10,2006,Kanazawa Excel Hotel Tokyu, Japan, Organized by: Kanazawa University 21st-Century COE Program, Environmental Monitoring and Prediction of Long- & Short- Term Dynamics of Pan-Japan Sea Area ; IICRC(Ishikawa International Cooperation Research Centre), Sponsors : Japan Sea Research ; UNU-IAS(United Nations University Institute of Advanced Studies)+Ishikawa Prefecture Government ; City of Kanazaw

Simultaneous in-situ multi-element analysis of minerals on thin section using LA-ICP-MS

Department of Earth Sciences, Faculty of Science, Kanazawa University:Graduate School of Natural Science and Technology, Kanazawa UniversityDepartment of Earth Sciences, Faculty of Science, Kanazawa University:Graduate School of Natural Science and Technology, Kanazawa UniversityDepartment of Earth Sciences, Faculty of Science, Kanazawa University:Graduate School of Natural Science and Technology, Kanazawa UniversityDepartment of Earth Sciences, Faculty of Science, Kanazawa University:Graduate School of Natural Science and Technology, Kanazawa UniversityIn-situ trace-element analyses on minerals are especially useful for characterization of geological materials. We explored optimistic conditions of a inductively coupled plasma mass spectroscopy with laser-ablation sample introduction method (LA-ICP-MS) for in-situ quantitative trace-element analysis of geological materials on thin section. The sampling with an excimer laser with energy density of 8 J/cm^2 is appropriate for in-situ analysis of minerals on thin section based on ablation hole morphology. The rate of material removal is estimated from deep holes on a glass after 500 shots with energy on sample surface of 8 J/cm^2 to be approximately 0.2ƒﾊm/pulse. 150-200 shots might be available for a sample prepared as normal thin section (30ƒﾊm in thickness). All data were obtained by ablating in He gas prior to combination with the dominant Ar carrier flow because ablation in He minimized post-ablation surface condensation, resulting in high sensitivity. We examined the relationship between the size of laser-ablation hole and sensitivity of analysis in conducting in-situ simultaneous quantitative LA-ICP-MS analysis of 37 elements including rare earth elements (REEs). The diameter of laser beam can be as small as 30ƒﾊm to obtain sufficiently good dataset for trace-element concentrations of minerals from thin section

Podiform chromitites in the lherzolite-dominant mantle section of the Isabela ophiolite, the Philippines

金沢大学理工研究域自然システム学系The Isabela ophiolite, the Philippines, is characterized by a lherzolite-dominant mantle section, which was probably formed beneath a slow-spreading mid-ocean ridge. Several podiform chromitites occur in the mantle section and grade into harzburgite to lherzolite. The chromitites show massive, nodular, layered and disseminated textures. Clinopyroxene (±orthopyroxene/amphibole) inclusions within chromian spinel (chromite hereafter) are commonly found in the massive-type chromitites. Large chromitites are found in relatively depleted harzburgite hosts having high-Cr# (Cr/(Cr + Al) atomic ratio = ∼0.5) chromite. Light rare earth element (LREE) contents of clinopyroxenes in harzburgites near the chromitites are higher than those in lherzolite with low-Cr# chromite, whereas heavy REE (HREE) contents of clinopyroxenes are lower in harzburgite than in lherzolite. The harzburgite near the chromitites is not a residual peridotite after simple melt extraction from lherzolite but is formed by open-system melting (partial melting associated with influx of primitive basaltic melt of deeper origin). Clinopyroxene inclusions within chromite in chromitites exhibit convex-shaped REE patterns with low HREE and high LREE (+Sr) abundances compared to the host peridotites. The chromitites were formed from a hybridized melt enriched with Cr, Si and incompatible elements (Na, LREE, Sr and H2O). The melt was produced by mixing of secondary melts after melt-rock interaction and the primitive basaltic melts in large melt conduits, probably coupled with a zone-refining effect. The Cr# of chromites in the chromitites ranges from 0.65 to 0.75 and is similar to those of arc-related magmas. The upper mantle section of the Isabela ophiolite was initially formed beneath a slow-spreading mid-ocean ridge, later introduced by arc-related magmatisms in response to a switch in tectonic setting during its obduction at a convergent margin. © 2006 The Authors; Journal compilation © 2006 Blackwell Publishing Asia Pty Ltd