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Measurement of the zodiacal light absolute intensity through Fraunhofer line spectroscopy of the night sky with the Hale telescope
Get PDFMeasuring the absolute brightness of the zodiacal light (ZL), which is the sunlight scattered by interplanetary dust particles, is important not only for understanding the physical properties of the dust but also for constraining the extragalactic background light (EBL) by subtracting the ZL foreground. We describe the results of high-resolution spectroscopic observations of the night sky in the wavelength range of 300–900 nm with the double spectrograph on the Hale telescope to determine the absolute brightness of the ZL continuum spectra from the Fraunhofer absorption line intensities. The observed fields are part of the fields observed by the Spitzer Space Telescope for the EBL study. Assuming that the spectral shape of the zodiacal light is identical to the solar spectrum in a narrow region around the Fraunhofer lines, we decomposed the observed sky brightness into multiple emission components by amplitude parameter fitting with spectral templates of the airglow, ZL, diffuse Galactic light, integrated starlight, and other isotropic components including EBL. As a result, the ZL component with the Ca ii λλ 393.3, 396.8 nm Fraunhofer lines around 400 nm is clearly separated from the others in all fields with uncertainties around 20%, mainly due to the template errors and the time variability of the airglow. The observed ZL brightness in most of the observed fields is consistent with the modeled ZL brightness calculated by combining the most conventional ZL model at 1250 nm based on the Diffuse Infrared Background Experiment and the observational ZL template spectrum based on the Hubble Space Telescope. However, the ecliptic plane observation is considerably fainter than the ZL model, and this discrepancy is discussed in terms of the optical properties of the interplanetary dust accreted in the ecliptic plane.journal articl
Gakken Hills Interdisciplinary Ekiden Competing with Humans, Animals, and Robots
Get PDFThe number of robots exiting in human living spaces has increased, and interaction between humans and robots has become an important issue. The purpose of this study is to propose a future society where humans, animals, and robots coexist. We organize relay race, or ekiden in Japanese, where they compete together as runners. The competition rules have been established to ensure that each runner can compete fairly. This paper explains the competition rules and discuss the fairness of the rulesconference pape
A new die-level flexible design-for-test architecture for 3D stacked ICs
No full textA die-level design-for-test architecture for 3D stacked ICs is proposed. The main component of this architecture is a newly proposed configurable boundary cell, based on which flexible parallel test is achieved. Both of the number of parallel scan chains and their lengths can be configured during test. This test architecture features light-weight, high flexibility in parallel test configuration, modularity, and IEEE P1149.1 compatibility. In this work, both infrastructure and implementation aspects are illustrated. Experimental results demonstrate desired test acceleration. The acceleration ratio approximately reaches its limit, which equals the number of parallel scan chains, when the number of test vectors is over 300.journal articl
IDLD: Interlocked Dual-Circle Latch Design with Low Cost and Triple-Node-Upset-Recovery for Aerospace Applications
Get PDFModern powerful CMOS chips are usually highly integrated and implemented with aggressively shrunk technology nodes. In radiation environment, under charge-sharing mechanism, one particle striking can simultaneously impact multiple nodes causing double-node-upsets (DNUs) and triple-node-upsets (TNUs). In this paper, we propose an Interlocked Dual-circle Latch Design, namely IDLD, with low cost and TNU recovery for aerospace applications. IDLD consists of four transmission gates and twelve 2-input C-elements (CEs) implemented in 22nm CMOS process. Simulation results demonstrate the complete TNU recovery as well as cost-effectiveness for the proposed IDLD latch.journal articl
Active Learning for Forward/Inverse Kinematics of Redundantly-driven Flexible Tensegrity Manipulator
Get PDFIn flexible redundantly-driven multi-DOF systems, like living beings, the representation of redundant kinematics including the diversity of solutions, is crucial for leveraging its distinctive characteristics. This paper proposes an active learning framework for forward and inverse modeling of complex kinematics that improves expressions of control space, task space, and null space. It consists of a Variational Auto Encoder (VAE)-type network that internally holds expressions of control space, task space, and null space, and an algorithm for selecting new data using the cross-entropy method. The validity of the proposed system was verified using a tensegrity manipulator driven by 40 pneumatic cylinders. As a result, it was confirmed that active learning contributed to achieving the entire range of motion covered and a well-organized representation of the null space.journal articl
Effects of Blink Frequency and Illumination on Avoidance Properties of Yellow-Phase Anguilla Japonica
Get PDFダムや堰の取水口に魚が迷入して減耗することが以前から問題となっている．特に水産価値の高いニホンウナギやアユなどの減耗は，地方経済への打撃となる恐れがある．迷入防止手段の一つとして，魚の忌避行動を誘発する光が挙げられる．連続光や点滅光が数魚種の忌避行動に与える影響が解明されつつあるが，ニホンウナギについては未解明である．本研究では，点滅光の点滅周波数を0.3～15Hz，照度を60～1300lxの範囲で変化させ，平均全長300mmの黄ニホンウナギの忌避特性に及ぼす影響を調査した．その結果，上記条件の点滅光をニホンウナギは忌避することおよび点滅周波数および照度の増加に伴いその傾向が顕著になることが解明された．得られた知見を現地に適用することで，ニホンウナギの迷入防止が達成されると期待される．It has been a problem that fish stray into the water intakes of dams and weirs and are injured. In particular, the depletion of Anguilla japonica and Plecoglossus altivelis, which have a high value in fisheries, is a serious problem that may damage the local economy. Light is one of a methods of inducing repellent behavior of fish. The effects of continuous and blinking light on the avoidance behavior of fishes have been elucidated, but very few studies have been conducted on Anguilla japonica. In this study, the blink frequency of flashing light were changed from 0.3 to 15 Hz and also the illuminance from 60 to 1300 lx using yellow-phase Anguilla japonica in 300 mm total length. It was found that Anguilla japonica avoided the flashing light in the present conditions and also that the repellent characteristics became more pronounced as the blinking frequency and illuminance increased. The range of blink frequency and illuminance must be expanded more than this study, so that the stray rate will be decreased and the population of Anguilla japonica will be increased.journal articl
YOLOv8s-NE: Enhancing Object Detection of Small Objects in Nursery Environments Based on Improved YOLOv8
Get PDFThe primary objective of this research investigation is to examine object detection within the specific environment of a nursery. The nursery environment presents a complex scene with a multitude of objects, varying in size and background. To simulate real-world conditions, we gathered data from a nursery. Our study is centered around the detection of small objects, particularly in nursery settings where objects that include stationery, toys, and small accessories are commonly present. These objects are of significant importance in facilitating cognition of the activities and interactions taking place within the confines of the room. Due to their small size and the possibility of occlusion by other objects or children, precisely detecting these objects is regrettably fraught with inherent challenges. This study introduces YOLOv8s-NE in an effort to enhance the detection of small objects found in the nursery. We improve the standard YOLOv8 by incorporating an extra detection head to effectively for small objects. We replace the C2f module with C2f_DCN to further improve the model’s ability to detect objects of varying sizes that can be deformed or occluded within the image. Furthermore, we introduce NAM attention to focus on the important features and ignore less informative ones, thereby improving the accuracy of our proposed model. We used the five-fold cross-validation approach to split the dataset in order to evaluate the performance of YOLOv8s-NE, thereby facilitating a more comprehensive model evaluation. Our model achieves 34.1% of APs, 45.1% of mAP50:90, and 76.7% of mAP50 detection accuracy at 37.55 FPS on the nursery dataset. In terms of APs, mAP50:90, and mAP50 metrics, our proposed YOLOv8s-NE model outperforms the standard YOLOv8s model, with improvements of 4.6%, 4.7%, and 3.9%, respectively. We apply our proposed YOLOv8s-NE model as a safety system by developing an algorithm to detect objects on top of cabinets that could be potentially risky to children.journal articl
変形性膝関節症患者の動作解析と装着圧力に着目した膝装具の開発
Get PDF九州工業大学博士（工学）1 序論| 2 膝OAの病態・診断・症状・治療| 3 軟性膝装具の多角的解析と装着圧力に着目した開発装具の提案| 4 膝OA患者の立ち上がり動作における膝装具効果| 5 膝OA患者の歩行動作における膝装具効果| 6 膝OA患者の関節位置覚における膝装具効果| 7 装着圧力に着目した膝装具の開発と有用性| 8 結論九州工業大学博士学位論文 学位記番号:生工博甲第484号 学位授与年月日:令和6年3月25日令和5年度doctoral thesi
Hardware Implementation of Calibration Data Loading in Device Driver for an SPI Peripheral
Get PDFAs the IoT progresses, various SoCs are being developed. If a SoC is in high demand, the development cost per chip is small, but if the demand is localized, the development cost is large, resulting in more expensive products. To solve this problem, we aim to develop a general-purpose SoC with hardware interfaces for all peripheral devices. Since it is difficult to develop such a SoC due to hardware constraints, the dynamic reconfiguration of FPGA is used to deploy only what is necessary for processing in the reconfiguration unit. In addition, we aim to develop a general-purpose architecture that facilitates the design and development of dedicated hardware interfaces for each peripheral device. This architecture is to achieve a general-purpose SoC by seeking the cooperation of engineers around the world. Toward the development of this architecture, we will first focus on SPI devices. In developing hardware device drivers for SPI devices, RTL description is used for the parts that describe clock-cycle-based operations, and high-level synthesis is used for the parts that describe procedure-based operations. In this study, the BME280, a temperature, humidity, and barometric pressure sensor for SPI devices, is used to convert the device driver functionality to hardware for efficient use. This paper describes the hardware implementation of the part that reads multiple calibration data to correct the sensor data, and evaluates the performance, circuit size, and power efficiency through demonstration experiments using an actual device.journal articl
Centrifuge Model Tests on Effect of Levee Soil Characteristics on Erosion Process During Overtopping
Get PDF洪水規模の拡大によって計画高水位を超過した越水による堤防決壊が毎年のように発生し，近年では越水に対して粘り強さを発揮できる堤防強化工法の検討が進んでいる．効果的な堤防強化工法の立案のためには，堤体土質が浸食プロセスに及ぼす影響等の不明な点を明らかにする必要がある．本研究では，粒度特性を変化させた堤体材料を用いて模型堤防を作製し，縮尺模型に任意の重力加速度を載荷することで実地盤の応力状態を再現できる遠心載荷実験中に越水実験を行った．その結果，越水時の堤体浸食速度は無次元限界掃流力と見かけの粘着力と関連していることがわかった．このことから越水に対する土堤の粘り強さの評価には，従来の水理学的パラメータに加えて，地盤工学的なパラメータの勘案が有用である．journal articl