Cloud Internet of Things for the Smart Environment of a Smart City

The environmental service area for smart city construction provides sustainability, economic, stage, and safe energy savings in building a smart city. The smart environment monitoring system can manage the agricultural environment, water quality, and air quality of smart cities through the Internet of Things and cloud computing technology. Smart environmental monitoring (SEM) systems to reduce environmental problems in smart cities are important service domains that can improve citizens\u27 quality of life. The purpose of this project is to identify services through the introduction of technologies to solve environmental problems in smart cities, the use and management of the technologies introduced. The project findings are: (a) The SEM system collects environmental data through IoT devices and analyzes it through cloud computing. (b) Data from the SEM system is collected through the Internet of Things based on a wireless sensor network. The collected data is transmitted to the cloud computing platform to be analyzed and monitored. (c) For wireless Internet connections between the two technologies can connect through unique services of Message Queuing Telemetry Transport and cloud platform. (d) The SEM applications were analyzed for Smart Agricultural Monitoring, Smart Water Quality Monitoring, and Smart Air Quality Monitoring. (e) The project is analyzed the transmitted data using Amazon Web Service and Google Cloud Platform. When the analyzed environmental parameters deviate from normal values, email notification can be sent to detect abnormalities in environmental parameters. In addition, the connection between IoT devices and cloud platforms can confirm the normal connection of IoT devices to establish a security system by obtaining credibility and reliability for the connection between the two technologies. As a result, the collaboration between IoT and cloud computing technology can show how a smart environment service domain can help smart city citizens

Design and Implementation of a Wireless Charging-Based Cardiac Monitoring System Focused on Temperature Reduction and Robust Power Transfer Efficiency

Wireless power transfer systems are increasingly used as a means of charging implantable medical devices. However, the heat or thermal radiation from the wireless power transfer system can be harmful to biological tissue. In this research, we designed and implemented a wireless power transfer system-based implantable medical device with low thermal radiation, achieving 44.5% coil-to-coil efficiency. To suppress thermal radiation from the transmitting coil during charging, we minimized the ESR value of the transmitting coil. To increase power transfer efficiency, a ferrite film was applied on the receiving part. Based on analyses, we fabricated a cardiac monitoring system with dimensions of 17 x 24 x 8 mm(3) and implanted it in a rat. We confirmed that the temperature of the wireless charging device increased by only 2 degrees C during the 70 min charging, which makes it safe enough to use as an implantable medical device charging system.11Ysciescopu

Highly tunable repetition-rate multiplication of mode-locked lasers using all-fibre harmonic injection locking

Higher repetition-rate optical pulse trains have been desired for various applications such as high-bit-rate optical communication, photonic analogue-to-digital conversion, and multi- photon imaging. Generation of multi GHz and higher repetition-rate optical pulse trains directly from mode-locked oscillators is often challenging. As an alternative, harmonic injection locking can be applied for extra-cavity repetition-rate multiplication (RRM). Here we have investigated the operation conditions and achievable performances of all-fibre, highly tunable harmonic injection locking-based pulse RRM. We show that, with slight tuning of slave laser length, highly tunable RRM is possible from a multiplication factor of 2 to >100. The resulting maximum SMSR is 41 dB when multiplied by a factor of two. We further characterize the noise properties of the multiplied signal in terms of phase noise and relative intensity noise. The resulting absolute rms timing jitter of the multiplied signal is in the range of 20 fs to 60 fs (10 kHz - 1 MHz) for different multiplication factors. With its high tunability, simple and robust all-fibre implementation, and low excess noise, the demonstrated RRM system may find diverse applications in microwave photonics, optical communications, photonic analogue-to-digital conversion, and clock distribution networks.Comment: 25 pages, 9 figure

Seismic damage identification of cable-stayed bridge in near-real-time using unsupervised deep neural network

The 20th working conference of the IFIP Working Group 7.5 on Reliability and Optimization of Structural Systems (IFIP 2022) will be held at Kyoto University, Kyoto, Japan, September 19-20, 2022.Prompt damage identification of infrastructure systems is essential for effective post-disaster responses. However, most infrastructure systems have a high level of structural complexity, making damage identification extremely difficult. To overcome the challenge, the authors recently proposed a deep neural network (DNN) based framework for identifying the seismic damage based on the structural response data recorded during an earthquake event (Kim and Song, 2022). The DNN of the proposed framework is constructed by a Variational Autoencoder, one of the self-supervised DNNs capable of constructing a continuous latent space of input data by learning probabilistic characteristics. The DNN model is trained using the covariance matrices of the snapshot of the response data obtained from the undamaged structure. To consider the load-de-pendency, the undamaged state of the structure is represented by the covariance matrix, which is closest to that obtained from the measured seismic response in the latent space. To identify the severity of the structural damage, a structural damage index based on the difference in the covariance matrices is introduced. This paper improves the DNN-based framework to facilitate its applications to complex structural systems such as the Incheon Grand Bridge, a reinforced concrete cable-stayed bridge in South Korea. To generate train, validation, and test datasets, structural analyses are first performed under the ground motions from the PEER-NGA strong motion data-base. The proposed framework is verified with near-real-time simulations using ground motions with various time steps from the test dataset. The example shows that the proposed framework can accurately identify seismic damage of the complex structural system in near-real-time

Nanomechanical characterization of quantum interference in a topological insulator nanowire

The discovery of two-dimensional gapless Dirac fermions in graphene and topological insulators (TI) has sparked extensive ongoing research toward applications of their unique electronic properties. The gapless surface states in three-dimensional insulators indicate a distinct topological phase of matter with a non-trivial Z2 invariant that can be verified by angle-resolved photoemission spectroscopy or magnetoresistance quantum oscillation. In TI nanowires, the gapless surface states exhibit Aharonov-Bohm (AB) oscillations in conductance, with this quantum interference effect accompanying a change in the number of transverse one-dimensional modes in transport. Thus, while the density of states (DOS) of such nanowires is expected to show such AB oscillation, this effect has yet to be observed. Here, we adopt nanomechanical measurements that reveal AB oscillations in the DOS of a topological insulator. The TI nanowire under study is an electromechanical resonator embedded in an electrical circuit, and quantum capacitance effects from DOS oscillation modulate the circuit capacitance thereby altering the spring constant to generate mechanical resonant frequency shifts. Detection of the quantum capacitance effects from surface-state DOS is facilitated by the small effective capacitances and high quality factors of nanomechanical resonators, and as such the present technique could be extended to study diverse quantum materials at nanoscale.Comment: 15+16 pages, 4+11 figure

A Wireless Power Transfer Based Implantable ECG Monitoring Device

Implantable medical devices (IMDs) enable patients to monitor their health anytime and receive treatment anywhere. However, due to the limited capacity of a battery, their functionalities are restricted, and the devices may not achieve their intended potential fully. The most promising way to solve this limited capacity problem is wireless power transfer (WPT) technology. In this study, a WPT based implantable electrocardiogram (ECG) monitoring device that continuously records ECG data has been proposed, and its effectiveness is verified through an animal experiment using a rat model. Our proposed device is designed to be of size 24 x 27 x 8 mm, and it is small enough to be implanted in the rat. The device transmits data continuously using a low power Bluetooth Low Energy (BLE) communication technology. To charge the battery wirelessly, transmitting (Tx) and receiving (Rx) antennas were designed and fabricated. The animal experiment results clearly showed that our WPT system enables the device to monitor the ECG of a heart in various conditions continuously, while transmitting all ECG data in real-time.11Ysciescopu

Research on Voyage Navigation S/W Development Architecture Using Open Source Base GIS Modules

Recently, as the number of voyage accident is increasing, massive damage of human life and property is following depends on scale of accident. ECDIS is navigation equipment essential for safe sailing and clean marine environment. However, ECDIS S/W is relatively expensive, and ocean-related international organizations such as IMO and IHO are designing the programs mainly for medium and large ships. OPEN CPN, SeaClear are existing as product based on Open Source Project, however they are lack of functions to use in actual voyage. ECDIS development by making combination with modules based on open source could be an alternative to follow the standards and develop efficiently