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Analysing the impact of energy price increases on the vulnerable using the fuel poverty index: a case study of Kobe, Japan
Get PDFThe global economic recovery from the COVID-19 pandemic and the Russian invasion of Ukraine have significantly increased global energy prices, resulting in higher household burdens for citizens. This study uses fuel poverty indicators to determine household vulnerability to increase in energy price in Japan. A web questionnaire was conducted asking about household income and fuel bills in 2021 and 2022, using Kobe City, Japan, as a case study. As the result, the percentage of fuel-poor households in 2022 was 5.39%, an increase of 0.23% over 2021. This suggests that fuel-poor households are increasing in response to increasing energy prices. The 2022 fuel poverty rate for elderly households was 1.48%, and it was 3.91% for households other than the elderly. Analysis result regarding the characteristics of households determined to be fuel-poor indicated that single-parent households were more likely to fall into fuel poverty than average households. A model combining binomial logistic regression and multiple regression analyses was derived to measure the effect of fuel poverty measures based on the questionnaire survey results. The study results of measures to reduce the time spent using climatization equipment during the daytime in summer by implementing energy sharing showed that all households and single-parent households could move out of fuel poverty. However, elderly households could not move out of fuel poverty, and an additional condition for breaking out of fuel poverty was an increase in the annual household income of elderly households by 0.2 million JPY (Japanese Yen).journal articl
Geometric Analysis of the Generating Mechanism for Machined Surfaces in Radius End Milling—Calculation Method for the Shape of Machined Surfaces and Its Dependence on the Tool Axis Direction —
Get PDFThis study aims to geometrically analyze the generating mechanism of machined surfaces in radius end milling. In this report, to clarify the dependence of the machined surface shape on the tool axis direction, we propose an iterative calculation method to determine parameter values using approximate ruled surfaces and the internal division ratio of sections including their endpoints. By applying this method to calculate the machined surface shape for 792 combinations of tool axis direction, it was found that the maximum Rz of 21.0 μm occurred at a slant angle of 55°and a bearing angle of 270°. In contrast, the minimum Rz of 6.4 μm occurred at a slant angle of 5°and a bearing angle of 60°.journal articl
Resilient mobility of a four-wheeled planetary rover with active suspension
No full textThis article presents a comprehensive study of the resilient mobility of a four-wheeled lunar rover under various internal and external environmental conditions. The proposed and analyzed mobility approach enhances the adaptability and robustness of a rover with limited resources in harsh environments. An innovative omnidirectional inching locomotion technique was introduced to reinforce access to challenging terrain. This technique was compared with conventional locomotion methods through drawbar pull tests and analyzes using resistive force theory (RFT). Emphasis was placed on functional isolation during actuator failure, achieved by implementing a one-way clutch mechanism. This resilient design ensures the core functionality of the rover and mitigates resource wastage in critical scenarios. The experimental and analytical results highlight the capability of the rover to manage potential actuator failures, offering valuable insights into its adaptability to demanding lunar-like environments. This work demonstrates the capacity of the rover to overcome challenges and efficiently navigate diverse terrain, making it a promising candidate for lunar exploration and construction.journal articl
Optimum Channel Slope and Fishladder Length for Anguilla Japonica Migration
Get PDFダムや堰による魚類の遡上阻害を解消する目的で魚道が併設される．欧州ではウナギ用魚道の開発が進行中だが，最適な傾斜角や魚道長等は未解明である．本研究では底面に円柱突起物を有するウナギ用魚道の傾斜角と魚道長を15～45°，0.4～2.0mの範囲で変化させ，ニホンウナギの遡上特性に及ぼす影響を調査した．その結果，魚道長の増加に伴い遡上速度および蛇行度が増加し停滞率が減少すること，また，遡上率および遡上成功率が減少し，この傾向が魚道長0.8m以上で顕著になることが解明された．一方，傾斜角30°で遡上率が最大となった．以上より，全長200mmのニホンウナギの遡上に適したウナギ用魚道の傾斜角は30°で魚道長は0.4～0.8mであること，魚道を連続設置する際は接続部に休憩場所の設置が必要との結論を得た．Most fishladders in Japan are designed for swimming fish and are not effective for benthic one such as eels. In Europe, ramp-type fishladders are sometimes installed for eels, but the optimum geometrical shape has not been clarified. In this study, the channel slope and fishladder length were changed. It was found that the migration and success rate decreased with increasing the fishladder length from 0.4 to 2.0m, and the migration rate was about 0.7 for fisladder length between 0.4 and 0.8m when the channel slope was 30 degree. The migration swimming speed and sinuosity increased with increasing the fishladder length, and the stagnation rate decreased. In the range of the experimental conditions, the optimum fishladder length was in the rage between 0.4 and 0.8m and channel slope is 30 degree for the 200mm total length of Anguilla japonica.journal articl
Detection of Lung Nodules from Temporal Subtraction CT Image Using Elastic Net-Based Features Selection
Get PDFCT (computed tomography) is mainly used to diagnose lung cancer. Many CT images impose a heavy burden on visual screening, so a CAD (computer-aided diagnosis) system is expected to reduce the burden. In this paper, we propose an image analysis method to detect lung nodules from chest CT images using machine learning techniques. The best results were obtained for the method using LightGBM with feature reduction by Elastic Net.conference pape
Non-Invasive Classification of EGFR Mutation from Thoracic CT Images Using Radiomics Features and LightGBM
Get PDFCancer caused 9.7 million deaths in 2022, including 1.8 million from lung cancer the leading cause of cancer death. EGFR mutation testing is essential for lung cancer treatment planning, but it is invasive and visual identification from chest CT images is difficult. This paper proposes a computer-aided diagnosis system to identify EGFR mutation status. Lung tumor regions were automatically extracted and radiomics features were obtained. Dimensionality reduction was performed using null importance, variance inflation factor, and recursive feature elimination. The method was applied to 143 cases and achieved an accuracy of 59.1%, a true positive rate of 54.3% and a false positive rate of 36.1%. The results suggest that CAD (Computer-Aided Diagnosis) systems can improve the non-invasive detection of EGFR mutations in lung cancer.conference pape
Electrochemically active DNA ligands for gene detection: present and future
No full textElectrochemical gene sensing methods are gaining attention as diagnostic chips. Here, we review the electrochemically active DNA ligand-based sensing methods. Various DNA ligands have been reported in these studies, among which metal complexes, methylene blue, and ferrocenyl naphthalene diimide (FND) have been studied in detail. DNA probe immobilized electrodes have been created, hybridization reactions on the electrodes with target DNA fragments have been performed, and electrochemical gene detection has been possible using these DNA ligands. An example of the realization of this system is the successful and accurate cancer diagnosis using FND to examine abnormal methylation of the hTERT gene, providing reassurance about the system's reliability. In addition, electrochemical detection of PCR products has been realized using the current decrease due to the double-stranded DNA binding of methylene blue although it is a signal-off system. A naphthalene diimide derivative with ferrocene and β-CD, FNC, increased the current upon double-stranded DNA binding. Using these FNCs, the detection of PCR products in a homogeneous system was realized. Electrochemical qPCR was realized with these ligands. Since FNDs also bind strongly to tetraplex or G-quadruplex (G4) DNA, we succeeded in electrochemically detecting telomerase activity, which is known as a cancer marker, using FNDs to detect the amount of telomeric DNA elongation, which is its substrate, as the amount of G4 DNA. This technique has realized compassionate cancer diagnosis from oral swab fluid. It is known that G4 is also present in viral genome RNA, and a viral testing method using G4 is expected to be a potential alternative to PCR. The first example was the electrochemical detection of novel coronaviruses using incFND as an RNA G4 ligand.journal articl
Modulation of nonlinearity and asymmetry in a spin-orbit torque driven artificial synapse
Get PDFUnconventional computing schemes inspired by biological neural networks are being explored with ever growing interest to eventually replace traditional von Neumann architecture-based computation. Realization of such schemes necessitates the development of device analogs to biological neurons and synapses. Particularly, in spin-based artificial synapses, the spin–orbit torque (SOT) can be utilized for changing between multiple resistance states of the synapse. In this work, we demonstrate synaptic behavior, namely long-term potentiation and long-term depression in a ferrimagnet (GdFe) via SOT generated using a heavy metal (Pt). The dependence of the synapse-like output on the input parameters is extensively investigated. Synaptic arrays based on experimental results are simulated and used to perform the classification of a handwritten digit dataset. Correlating the classification accuracy with the experimentally observed synaptic behavior, the performance of the synapse is found to depend on the critical switching currents. Understanding the correlation between the input parameters and synaptic performance could accelerate the development of artificial spintronic synapses possessing high operation speed, nonvolatility and plasticity, thereby enabling efficient compute in-memory systems in the near future.journal articl
Signal Decomposition and Noise Reduction in Single-Channel EEG: A Morphological Component Analysis (MCA) Approach
Get PDFThis study applies the Morphological Component Analysis (MCA) to single-channel EEG data obtained during human-to-human interactions in a board game (Hex-game). MCA, a dictionary-based signal decomposition method, separates signals into distinct morphological components. It enables the extraction of plausible brain activity and the removal of noise, such as ocular and muscular artifacts. By focusing on neural dynamics in interactive settings, this approach highlights the relationship between cognitive processes and social behavior. The approach suggests that MCA offers a promising framework for EEG analysis in complex, dynamic environments, combining effective feature extraction with robust artifact removal.conference pape