土着微細藻類を原料とした溶媒抽出と連続水熱液化処理によるバイオ燃料生産

この博士論文は内容の要約のみの公開（または一部非公開）になっています筑波大学 (University of Tsukuba)201

Fundamental design principles of novel MEMS based Landau switches, sensors, and actuators : Role of electrode geometry and operation regime

Microelectromechanical systems (MEMS) are considered as potential candidates for More-Moore and More-than-Moore applications due to their versatile use as sensors, switches, and actuators. Examples include accelerometers for sensing, RF-MEMS capacitive switches in communication, suspended-gate (SG) FETs in computation, and deformable mirrors in optics. In spite of the wide range of applications of MEMS in diverse fields, one of the major challenges for MEMS is their instability. Instability divides the operation into stable and unstable regimes and poses fundamental challenges for several applications. For example: Tuning range of deformable mirrors is fundamentally limited by pull-in instability, RF-MEMS capacitive switches suffer from the problem of hard landing, and intrinsic hysteresis of SG-FETs puts a lower bound on the minimum power dissipation. ^ In this thesis, we provide solutions to the application specific problems of MEMS and utilize operation in or close to unstable regime for performance enhancement in several novel applications. Specifically, we propose the following: (i) novel device concepts with nanostructured electrodes to address the aforementioned problems of instability, (ii) a switch with hysteresis-free ideal switching characteristics based on the operation in unstable regime, and (iii) a Flexure biosensor that operates at the boundary of the stable and unstable regimes to achieve improved sensitivity and signal-to-noise ratio. In general, we have advocated electrode geometry as a design variable for MEMS, and used MEMS as an illustrative example of Landau systems to advocate operation regime as a new design variabl

Synaptic, Cellular and Behavioral Pathophysiology in Anti-Gabab Receptor and Anti-Nmda Receptor Encephalitides

A new class of severe but treatable autoimmune encephalitides is associated with serum and CSF autoantibodies to cell surface receptors that are thought to cause disease by disrupting the normal function of their target protein. Consistent with disruption of the major neurotransmission pathways and thus circuit malfunction in the central nervous system, symptoms of these newly characterized diseases are severe and include psychosis, memory loss, confusion, seizures, and autonomic instability normal function. The majority of symptoms resolve with aggressive immunosuppresive therapy. The best characterized of these encephalitides is associated with antibodies to ionotropic glutamate receptors, N-methyl-D-aspartate receptor (NMDAR) or α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR). NMDAR and AMPAR autoantibodies cross-link the cognate synaptic receptors on the surface of cultured neurons and result in a selective internalization of the target without disruption of any other synaptic component or injury to neurons. In a passive transfer animal model, chronic perfusion of NMDAR antibodies into the cerebrospinal fluid (CSF) of mice also decreases NMDA receptors after 14 days, which results in anhedonia and diminished spatial memory. Consistent with the reversible course of disease, the effects of NMDAR and AMPAR autoantibodies can be reversed in both in vivo and in vitro model systems. These mechanisms may underlie the neurological and psychiatric manifestations of these forms of autoimmune encephalitis, and account for recovery of many patients with immune therapy aimed at lowering antibody titer. Patients with antibodies to the metabotropic gamma-aminobutyric acid receptor type B (GABAB receptor) develop severe intractable seizures, but little is known about the underlying pathophysiological mechanisms. Deletion mapping and expression in heterologous cells showed that patient anti-GABAB antibodies bind to alternatively spliced Sushi domains present in the presynaptically localized GABAB1a isoform. In contrast to patient anti-NMDAR antibodies, GABAB autoantibodies did not result in a decrease in surface GABAB receptors or their internalization. Treating neurons with GABABR autoantibodies for two hours blocked the activation of GABAB receptors by baclofen in a titer-dependent manner. Autoantibody-bound GABABRs are still signaling competent, because baclofen block was circumvented by directly activating GABAB2 with a selective agonist, CGP7930. Patient GABAB receptor autoantibodies are selective GABAB1 antagonists that may contribute to seizures by interfering with GABA-mediated inhibition. Brain penetrant GABAB2 agonists may be useful to treat intractable seizures in anti-GABAB receptor encephalitis patients

A Watch-List Based Classification System

Watch-list-based classification and verification is advantageous in a variety of surveillance applications. In this thesis, we present an approach for verifying if a query image lies in a predefined set of target samples (the watch-list) or not. This approach is particularly useful at identifying a small set of target subjects and therefore can render high levels of accuracy. Further, this approach can also be extended to identify the query image exactly out of the target samples. The three- stages approach proposed here consists of using a combination of color and texture features to represent the image and further using, Kernel Partial Least Squares for dimensionality reduction followed by a classifier. This approach provides improved accuracy as shown by experiments on two datasets

土着微細藻類を原料とした溶媒抽出と連続水熱液化処理によるバイオ燃料生産

筑波大学 (University of Tsukuba)201

Simulation studies to evaluate the impact of receiver clock modelling in flight navigation

GNSS based positioning and navigation always require perfect synchronization between the receiver and satellites clock. Further, due to the limited frequency stability of the GNSS receiver’s internal oscillator, an additional receiver clock error has to be estimated along with the coordinates. Thus, the observation geometry is changed; it results in some disadvantages which are: at least four satellites are required for positioning or navigation, high correlations are generated among the estimated receiver clock, the up-component and tropospheric delay, and the up-component is estimated less precisely than the horizontal coordinates. Research has shown that these drawbacks can be avoided by replacing the receiver internal oscillator with a more stable external clock and modelling its operation in a physically meaningful way over intervals in which the oscillator noise is far less than the observation noise. This method is known as receiver clock modelling (RCM). In this contribution, we will present a simulation study which is done to evaluate the gain in performance by RCM in code-based GNSS flight navigation where the height component is of relevance. Different flight test trajectories are simulated with code observation of a multi-GNSS system. Observations for different test trajectories are evaluated with and without RCM using different types of external clocks. The gain in precision of the coordinates for different trajectories w.r.t different clocks will be presented.Deutsches Zentrum für Luft- und Raumfahrt e.V./DLR Raumfahrtmanagement/FKZ: 50NA1705/E

Performance evaluation of GNSS receiver clock modelling in urban navigation using geodetic and high-sensitivity receivers

In urban areas, the Global Navigation Satellite System (GNSS) can lead to position errors of tens of meters due to signal obstruction and severe multipath effects. In cases of 3D-positioning, the vertical coordinate is estimated less accurately than are the horizontal coordinates. Multisensor systems can enhance navigation performance in terms of accuracy, availability, continuity and integrity. However, the addition of multiple sensors increases the system cost, and thereby the applicability to low-cost applications is limited. By using the concept of receiver clock modelling (RCM), the position estimation can be made more robust; the use of high-sensitivity (HS) GNSS receivers can improve the system availability and continuity. This paper investigates the integration of a low-cost HS GNSS receiver with an external clock in urban conditions; subsequently, the gain in the navigation performance is evaluated. GNSS kinematic data is recorded in an urban environment with multiple geodetic-grade and HS receivers. The external clock stability information is incorporated through the process noise matrix in a Kalman filter when estimating the position, velocity and time states. Results shows that the improvement in the precision of the height component and vertical velocity with both receivers is about 70% with RCM compared with the estimates obtained without applying RCM. Pertaining accuracy, the improvement in height with RCM is found to be about 70% and 50% with geodetic and HS receivers, respectively. In terms of availability, the HS receiver delivers an 100% output compared with a geodetic receiver, which provides an output 99⋅4% of the total experiment duration. Copyright © The Author(s), 2021. Published by Cambridge University Press on behalf of The Royal Institute of Navigation.