The Monte Carlo Approach to State Estimation for Linear Dynamical Systems with State-Dependent Measurement Noise

This paper is concerned with the state estimation of linear dynamical systems with state-dependent measurement noise. The minimum variance estimate of the state is obtained as the weighted mean of the outputs of Kalman filters parameterized by the state-dependent measurement noise sequences. The usual calculation for this estimate, however, becomes impractical since a very large amount of outputs of Kalman filters is required. Therefore, we regard the set of all the state-dependent measurement noise sequences as a population. Then, we evaluate the minimum variance estimate on the basis of a relatively small number of outputs of Kalman filters, parameterized by the state-dependent measurement noise sequences sampled at random from the population. The convergence of the algorithm is established. Then, by an approximation of a sampling procedure with a fast convergence property, a feasible sampling procedure is determined and a practical algorithm is designed. This policy of design leads to an efficient algorithm. Digital simulation results show a good performance of the proposed algorithm

Competences in Project Management: A Case Study in Osaka Institute of Technology

This chapter briefly explains the distributed project management of four joint departments for first-grade joint project-based learning (PBL). That is, conventional studies and purpose, capital, competence and ability of four kinds of distributed project management were presented, and relations among them are shown after describing background (included prehistory of PBL in Osaka Institute of Technology (O.I.T.)). Then, consideration and analysis about communication, interaction, cooperation, merit, week-point, effect and inference were discussed. Some case studies were described about open innovation and competences in stakeholder management. They were distinctive and superior in first-grade PBL of O.I.T. Finally, some future themes were presented

Development of ground pipeline system for high-level scientific data products of the Hisaki satellite mission and its application to planetary space weather

The Hisaki satellite is the first-ever space telescope mission dedicated to planetary sciences. Atmospheres and magnetospheres of our solar system planets are continuously monitored by the extreme ultraviolet (EUV) spectrometer onboard Hisaki. This paper describes a data pipeline system developed for processing high-level scientific and ancillary data products from the Hisaki mission. The telemetry data downlinked from the satellite are stored in a ground telemetry database, processed in the pipeline to imaging spectral data with a 1-min temporal resolution and ancillary data products, and then archived in a public database. The imaging spectra can be further reduced to higher-level data products for practical scientific use. For example, light curves of the power emitted from Jupiter’s aurora and plasma torus with a temporal resolution of 10-min can be reduced from the imaging spectral data; the reduced light curves reveal the transport processes of energy and mass in Jupiter’s magnetosphere and associated interplanetary solar wind conditions. Continuous monitoring with Hisaki will contribute considerably to our understanding of space weather relating to planets in our solar system

Single longitudinal mode narrow linewidth thulium-doped fiber laser based on an eye-shaped dual-ring filter

A single-longitudinal-mode (SLM) thulium-doped fiber laser, based on an eye-shaped passive dual-ring filter, is designed and constructed. The eye-shaped passive compound cavity consisting of four couplers is used to increase the longitudinal mode spacing, and its performance is numerically analyzed in detail. A homemade uniform fiber Bragg grating serves as a wavelength selection device and a saturable absorber is used to further suppress the intense longitudinal mode competition in the laser cavity, ensuring the single-longitudinal-mode output. The experimental results demonstrate a laser output with a center wavelength of 2,049.85 nm and an optical signal-to-noise ratio of 63 dB. Moreover, the power fluctuation is less than 0.6 dB, and the center wavelength fluctuation is less than 0.03 nm over a continuous measurement period of 60 min, demonstrating an excellent stability. The laser linewidth is measured using an unbalanced Michelson interferometer and β-separation line method, resulting in a linewidth of 11.22 kHz

Increased Stathmin1 Expression in the Dentate Gyrus of Mice Causes Abnormal Axonal Arborizations

Pituitary adenylate cyclase-activating polypeptide (PACAP) is involved in multiple brain functions. To clarify the cause of abnormal behavior in PACAP deficient-mice, we attempted the identification of genes whose expression was altered in the dentate gyrus of PACAP-deficient mice using the differential display method. Expression of stathmin1 was up-regulated in the dentate gyrus at both the mRNA and protein levels. PACAP stimulation inhibited stathmin1 expression in PC12 cells, while increased stathmin1expression in neurons of the subgranular zone and in primary cultured hippocampal neurons induced abnormal arborization of axons. We also investigated the pathways involved in PACAP deficiency. Ascl1 binds to E10 box of the stathmin1 promoter and increases stathmin1 expression. Inhibitory bHLH proteins (Hes1 and Id3) were rapidly up-regulated by PACAP stimulation, and Hes1 could suppress Ascl1 expression and Id3 could inhibit Ascl1 signaling. We also detected an increase of stathmin1 expression in the brains of schizophrenic patients. These results suggest that up-regulation of stathmin1 in the dentate gyrus, secondary to PACAP deficiency, may create abnormal neuronal circuits that cause abnormal behavior