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A Study on the Issues to Promote Transportations of Passengers and Cargos Using Buses
Get PDF本研究は、貨客混載を実施する交通事業者が事業推進上の問題をいかに認識しているかを把握する第１段階として、バス事業者3社を対象にヒアリング調査を行い、事業の成立過程、事業スキーム(路線、価格、ダイヤ等)等の実態や、制度や行政の役割等に関するバス事業者の考え方を整理したものである。調査の結果、従来指摘されている行政の役割や事業収入の取り扱い方等の課題に加え、a)バス事業者と宅配事業者の拠点位置関係や制度的制約により、必ずしも効率的な運行経路がとれない場合があること、b)荷物の重量やサイズに関する規定運用が明確でなく、混乱が生じる場合があること、c)委託金額算定の基準や根拠が様々であること、d)過疎地域では貨物量が小さく、車両改造費補助は事業インセンティブになっていないこと等の課題が明らかとなった。journal articl
Biodegradable Temperature Sensors with Enhanced Sensitivity Using Bioderived Ionic Liquid with Sodium Ions
Get PDFGels promise the development of flexible sensors for electronic and ionic skins owing to their high affinity for human skin, making them ideal for biomedical monitoring. Bioderived ionic liquids and their gels possess favorable physical and electrochemical characteristics, including extremely low vapor pressure, high ionic conductivity, and biodegradability, which suit applications of transient electronics requiring the autonomous decomposition of materials. However, their low temperature coefficient of resistance (TCR) may hinder the use of bioderived ionic liquids in wearable devices, implants, and environmental sensing. To address this issue, we doped sodium (Na) ions into the bioderived ionic liquid choline lactate to enhance its TCR for biodegradable temperature sensors. The Na ions improve the coupling of choline and lactate, resulting in a Na-doped ionic liquid with a high TCR, which is attributed to enhanced intermolecular interactions. The ionic gel, composed of the Na-doped ionic liquid and poly(vinyl alcohol), demonstrated a high thermal index of 7563 K, an activation energy of 1303 meV, and a TCR of 8.4%/K. The temperature sensor degraded in phosphate-buffered solution over 48 days, leaving the encapsulation layer. This study provides insight into enhancing the sensitivity of temperature sensors with ionic liquids for healthcare, wearable, and environmental applications.journal articl
Azobenzene-Modified Temperature-Responsive Short Elastin-like Peptides for Photo-Controlled Phase Transition
Get PDFElastin-like peptides (ELPs) have attracted attention as temperature-responsive biomaterials that can be used as drug carriers. In this study, temperature- and photoresponsive self-assembling peptide analogues were developed by conjugating short ELPs (total 20 amino acid residues) and azobenzene derivatives. The synthesized ELP–azobenzene conjugates exhibited reversible spectral changes upon UV or visible-light irradiation and temperature-responsive phase separation in aqueous solutions. The aggregation ability of the trans-isomers of the ELP–azobenzene conjugates was stronger than that of the cis-isomers. This phenomenon was attributed to the change in the hydrophilicity of the azobenzene moiety associated with photoisomerization from the trans- to the cis-isomer. In addition, aggregates of the ELP–azobenzene conjugate could be controlled by light irradiation. Therefore, this study provides a methodology for photo- and temperature-responsive ELP analogues with low molecular weights that can be easily synthesized by simple chemical reactions and are potential candidates for drug carriers that enable precise control of drug release.journal articl
Construction of a monitoring system for ablation plumes during YBCO thin film deposition by PLD method
Get PDFThis study used a depth camera to monitor the plume during YBa2Cu3Oy (YBCO) thin film deposition by pulsed laser deposition (PLD). Plume characteristics (height, width, and color) were changed by varying oxygen pressure and laser energy. Correlations between parameters were analyzed using principal component analysis (PCA), suggesting a correlation between plume color and composition. These results suggest that monitoring the plume is an effective way to improve the reproducibility of YBCO thin films.journal articl
Variable-Sensitivity Force Sensor Utilizing Modified Cross-Sectional Shape
Get PDFForce sensors require different measurement ranges and sensitivities depending on the operating environment. Therefore, we developed a force sensor with both variable sensitivity and measurement range based on structural modification induced by simple bending. In our previous study, we changed the distance between the force application point and the detection area. However, it was necessary to change the position and direction of the measured force. Therefore, in the present study, we changed the cross-sectional shape of the sensor. First, we introduce the theoretical basis for the proposed force sensor. We then describe prototype sensors and the experimental methods used to determine their performance. We fabricated the prototypes by attaching a strain gauge to one side of shape-memory polymer plates, which can be deformed at temperatures above the glass transition temperature (Tg) by applying a small load and maintain their rigid shape after they have been cooled below Tg. We designed two types of sensor with different cross-sectional shapes (i.e., hollow cylinder and channel beam) and experimentally evaluated them. The results indicated that the sensitivity and measurement range of the sensor can be changed by modifying the cross-sectional shape. For example, for hollow cylinder and channel beam types of sensor, the maximum change in sensitivity before and after bending was 6.2 and 2.7 times, respectively. Although these values were smaller than that (12 times) obtained in our previous study, it was possible to change the sensitivity without changing the position or direction of the measured force.journal articl
Development of Self-Calibration Hardware Interface for a Peripheral on Super General Purpose SoC
Get PDFThe advancement of the IoT (Internet of Things) has resulted in a diverse array of products. However, the costs of developing new SoCs (System on Chips) are on the rise due to technological progress. To address this, our goal is to create a super general purpose SoC with hardware interfaces that can accommodate various peripherals. Achieving this SoC would eliminate the need for repeated SoC development, lowering development costs. This highly adaptable SoC, designed to support all peripherals, would dynamically reconfigure dedicated hardware interfaces to suit each connected peripheral. We have proposed a general architecture of hardware interface that can be applied to any kind of physical peripheral. In that architecture, RTL (register transfer level) description, and high-level synthesis, HLS, are used for development. RTL description is used for the lower-level part that communicates with the peripherals. HLS is used for the higher-level portion, which handles processes that depend on specific peripherals. To demonstrate the compatibility and scalability of the proposed architecture, it is necessary to confirm the flexibility of the HLS hardware, HW. From the case study of the application to temperature and humidity sensors, we confirmed that it is both possible to separate HLS HWs for each type of data and to connect each of the signals that need to be shared, and to process multiple data with a single HLS HW. In this study, by using a 9-axis sensor and developing a self-calibration HW, we aim to confirm that it can cope with cases where pre-processing data is acquired intermittently. This paper evaluates the versatility, performance and power efficiency of the proposed architecture by means of actual machine verification.conference pape
Detection of Lung Nodules from CT Image Based on Ensemble Learning
Get PDFLung cancer is the most frequently diagnosed cancer worldwide and the leading cause of cancer-related deaths, making early detection and treatment crucial. Temporal subtraction system, one of the CAD, emphasize the differences between the current and previous images. In this study, radiomics features are extracted as explanatory variables from the temporal subtraction images. Feature selection is performed using Elastic Net, followed by the application of machine learning methods. Finally, ensemble learning is applied to classify unknown data into two categories: positive and negative lung nodules.conference pape
Developing a Sound-Based Method to Synchronize Multiple Videos Recorded by Multiple Sound Sources
Get PDFThe surround environmental monitoring from a vehicle on the road is important for the driving behavior analysis as well as the monitoring of driver's operations. A light weight mobile camera is useful for the record of multiple directions from the vehicle simultaneously. However, the timing synchronization is an important issue need to be solved. In this purpose, we proposed the sound-based method to synchronize different videos recorded with environmental sounds. In this task, the extraction of common sound features and amplifying of the features are necessary to superimpose those sound profiles to find consisting time points. In the validation the effectiveness, we used recoded videos from the bus driven by an expert driver.journal articl