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RELATIONSHIP BETWEEN GRAVITATIONAL SEDIMENTATION VELOCITY AND SEDIMENT PACKING FRACTION FOR SLURRIES WITH VARIOUS PARTCILES CONCENTRATION AND ASSEMBLING STATE
Get PDFGravitational sedimentation test has been used for characterization of various slurries, however, the relationship between the sedimentation velocity and sediment density is still unclear, even though they are both important properties. Thus, in this research, we conducted sedimentation tests with various particle concentration and assembling state to clarify their relation. For slurries in which hindered sedimentation occurs, the sediment density tends to increase with a decrease in the sedimentation velocity. This means that the slurry in which particles are well dispersed yields a low sedimentation velocity and a high sediment density. However, for slurries with comparative high particle concentration in which not only hindered sedimentation but also compression sedimentation occurs, the sedimentation velocity does not have a good connection with the sediment density. It is concluded that the sedimentation velocity changed complicatedly for compression sedimentation, resulting in the obscure relationship between the sedimentation velocity and sediment density
STUDY OF THE EXPLICIT FDTD METHOD USING THE ITERATED CRANK-NICOLSON SCHEME
Get PDFThe implicit finite-difference time-domain (FDTD) method has been developed using the Crank-Nicolson (CN) scheme, which provides highly accurate calculations. Note, however, that a large sparse matrix needs to be solved, making the FDTD calculation inefficient. In this work, we introduce an iterated Crank-Nicolson (ICN) scheme, which has widely been used in the area of computational relativity, into the FDTD method. In the ICN scheme, an implicit CN procedure can be replaced with an explicit iteration process. The formulation of the ICN-FDTD method is performed and the stability condition is derived. We analyze an optical waveguide, the facet of which is high-reflection coated with alternating dielectric layers. It is found that the results obtained from the ICN-FDTD method agree perfectly with those from the traditional explicit FDTD one
STUDY OF A REMOTE SEAL SYSTEM WITH INFORMATION HIDING FUNCTION
Get PDFAlthough telework has been introduced in many companies, there’re limitations on the tasks that can be teleworked. For example, tasks that require contact with an object, such as stamping, are difficult to be done electronically. We propose a remote assist system that uses Diminished Reality (DR) technology to maintain the confidentiality of information. The system enables workers who aren’t authorized to handle confidential information to perform their tasks without access to confidential information, while authorized employees can accomplish the tasks that require physical contact with the cooperation of the unauthorized workers. This presentation will introduce a remote seal system with information hiding functionality built using an open source software, TED (TelExistence Display System)
SPECTATOR SUPPORT TEXT GENERATION FOR COMPETITIVE FIGHTING GAMES
Get PDFIn the modern age, watching competitive fighting game tournaments as eSports has become a popular pastime, but it also requires knowledge of competitive games, making it difficult for spectators to watch the games. In this paper, a text generation system is proposed to support spectators by analyzing game content using object detection and posture estimation in order to lower the barrier to spectating
MACHINE LEARNING BASED ON DOCKER IMAGES VULNERABILITY QUANTITATIVE ASSESSMENT METHODOLOGY
Get PDFIn recent years, the market for cloud services has continued to expand, and the accompanying growth of "virtualization" has been remarkable. In particular, virtualization using containers is on the rise and is expected to become increasingly popular in the future, replacing conventional virtualization technologies. However, while the use of containers is growing, awareness of security is low, and there are problems such as being used by attackers and vulnerable applications being used without updating. In this study, we focus on Docker, one of the leading container technologies, and investigate the vulnerability of the images that compose the container, both official and other images. Based on the results, we provide Docker users with a more secure way to use containers
EVALUATION OF EXTERNAL MAGNETIC FIELD CORRECTION COIL FOR MEASUREMENT OF HYPERFINE STRUCTURE SPLITTINGS OF Rb ATOMS IN SUPERFULID HELIUM IN ACCELARATOR EXPERIMENTS
Get PDFWe have been developing a laser spectroscopic technique called OROCHI to study nuclear structure of low production yield unstable atom. In OROCHI, the energetic beams generated at an accelerator are stopped in superfluid helium (He II) with high efficiency (～100%). This method enables measurement of Zeeman level to determine the nuclear spins and hyperfine structure level to determine nuclear electromagnetic moments using laser radio wave/microwave double resonance method.In this study, we focused on the effect of the external magnetic field on the atoms, which is one of the causes limiting the accuracy of the measurement. By introducing an external magnetic field correction coil, we aim to measure the hyperfine structure splitting of unstable ^84Rb atoms with high precision that enables the derivation of hyperfine anomaly in the future
Development of Active Vibration Isolation for Gravitational Wave Detectors
Get PDFGround-based gravity wave detectors are limited in sensitivity by ground vibrations in the low frequency range. Ground vibration is continuous and random. Passive vibration isolation using mechanical characteristics such as pendulums or springs has no performance below the resonant frequency (~ several mHz). In this study, we aim at further vibration isolation at low frequencies by applying feedback control to an optical plate placed on top of a passive vibration isolation machine
DEVELOPMENT OF A CONSISTENT COLORDETECTION ALGORITHM USING COLORED REFERENCED PATCHES FOR MOBILE ROBOTS
Get PDFObserved color in images is easily affected by lighting conditions such as the sunlight location, weather, or time of day. Especially for image recognition processing on an outdoor navigated autonomous mobile robot, we should consider the effect of lighting conditions to achieve consistent robust color detection regardless of lighting condition change. In this paper, we employ new reference color patches to perform robust color detection to identify surrounding images by using the omnidirectional camera. As a demonstration of color detecting capability for the proposed approach, we apply specified human finding tasks defined by Tsukuba Challenge 2022 rules. Using the proposed method, we can demonstrate that the mobile robot was stably detected color, determining specified humans regardless of surrounding light change due to mobile robots
Development of an Interactive Risk Evaluation System using a Chatbot
Get PDFDuring the mobile robot development process, risk management is one of the primary issues to be solved, especially in cyber security for network-connected mobile robots. There is a huge and growing demand for remote mobile robot control while maintaining security, and the 2019 Intelligent Ground Vehicle Competition highlighted this compelling need with the Cyber Challenge has been introduced. The Challenge focuses on understanding the Risk Management Framework (RMF) and implementing and demonstrating it on a mobile robot; the RMF is designed for general purposes and cannot be directly applied to mobile robot scenarios. In this paper, we develop a novel interactive risk evaluation system for mobile robot scenarios. By providing mobile robot scenarios for which cybersecurity should be considered, Chatbot becomes an interactive questioner to find appropriate recommended risk management actions. In addition, unique evaluation criteria are established to visualize the threat level based on the suggestions. To realize an interactive risk evaluation system, we employed Slack API for the interactive communication analysis engine. To confirm the effectiveness of the proposed risk evaluation system, various scenarios from the IGVC2019 Design reports were applied to test and compared to the actual risk evaluations
MAGNETO-OPTICAL TRAPPING OF CS ATOMS TOWARD THE SEARCH FOR DARK MATTER USING QUANTUM SENSING
Get PDFWe developed the laser system, vacuum chambers, and microwave system toward the search for dark matter by quantum sensing using ultracold Cs atoms. The ultracold-atom experiment requires the frequency-stabilized lasers and vacuum chambers. The signals to stabilize the frequencies of lasers were obtained by frequency modulation (FM) spectroscopy, and by offset locking technique. We demonstrated magneto-optical trapping (MOT) of Cs atoms, and observed the absorption signal of the 6S_1/2 -5D_3/2 transition and 9.2 GHz microwave transitions between the hyperfine states of Cs for quantum sensing toward the search for dark matter