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With increasing heat-wave frequency, the prevention and public awareness of heat-related illnesses has become an essential topic. In the standard for heat strain and stress, empirical guidelines to prevent excess core temperature rise above 1 °C have been prescribed for workers. However, measuring core temperature change in our daily life or working place is not straightforward. The estimation of core temperature from measured vital signals in a non-invasive manner is thus essential for the management of heat stress or strain. Here, we propose an estimation method for core temperature change by a simplified thermodynamics model with the measured heart rate and ambient conditions (temperature and relative humidity). Our proposed model is based on a two-layer two-compartment model with tuned parameters, which were derived from comparison between the computations using high-resolution anatomical human body model. Our model exhibited good agreement with the measured core temperature rise; the computed and measured core temperature rise for the naked trial were 0.54 °C and 0.53 °C, whereas those for the clothed trial were 0.70 °C, and 0.71 °C, respectively. Furthermore, our compartment model with vital data measured from a wearable device achieved good estimation in real time for field measurement in addition to computational replication with a previous study.

This study addresses a closed-loop identification problem using routine operation data that include influences of periodic and stochastic disturbance. By using the periodicity, the proposed approach can estimate both model parameters and periodic disturbances. The paper also gives a new data-driven criterion and shows that its optimization uniquely obtains the actual model parameters and periodic disturbances. A simulation example demonstrates the validity of the proposed method.

This paper proposes noise-source parameter identification of the noise-source equivalent-circuit model for predicting conducted noise while considering the switching fluctuation of a DC/DC converter. We decomposed measured conducted noise into ripple noise, turn-on spike noise, and turn- off spike noise to prevent the accuracy degradation in the parameter identification. The predicted conducted noise spectra show the error with the measurement was within 3 dB up to 200 MHz, which is more accurate than that in our previous study.

In this paper, we propose a combination of digital polymerase chain reaction (dPCR) and melting curve analysis for the highly multiplexed genotyping of cell-free DNA (cfDNA) with high sensitivity. A silicon chip with 7.7x104 high-aspect-ratio wells with controlled surface hydrophobicity/hydrophilicity was developed. A sample containing cfDNA was divided into this large number of wells and amplified by PCR to enable sensitive detection. In addition, high multiplexing was achieved by capturing fluorescence images while controlling the temperature of the chip, measuring the melting curve for each well, and genotyping using fluorescence intensity, probe dye color, and melting temperature (Tm). The simultaneous dPCR genotyping of 10 types of DNA including single-nucleotide mutations of cancer-related genes was demonstrated for the first time with up to 7.7x104 wells.

We propose a fibre identification method based on temporary optical coupler and three-wavelength optical time domain reflectometry. We show that our technique can identify fibre termination states by analysing Fresnel reflection at three wavelength.

This paper proposes a parallel resonant power oscillator that has the load-independent characteristic. The proposed oscillator is the first parallel-resonant power oscillator for high frequency operations. In addition, it achieves the constant output voltage and the soft switching against the load variations without any control. The feedback network for generating a driving signal does not have a resonant structure and its function is not affected by the self-oscillation frequency. Therefore, the proposed oscillator also has a self-tuning function for the resonant-filter component tolerances. Because of the above characteristics, the proposed oscillator is expected to be used in many applications such as a transmitter of the wireless power transfer systems.

Future satellite SAR (SAT-SAR) will be required to provide more value-added observations in addition to constellation services. The SAT-SAR and sub-missions will need to be more sophisticated. This paper proposes applying KR product array processing to Digital Beam Forming (DBF) and synthetic aperture processing for the azimuth of the SAT-SAR. This paper presents the initial results of simulations for both high resolution and wide swath with about twice the Rx effective aperture length.

As the conducted disturbance of a power converter changes with its load value, the relationship between the electromagnetic interference of the power converter and its load needs to be investigated. This work examines a 2-port equivalent circuit model for a DC/DC buck converter with consideration of the load effect. Factors that influence the model accuracy are also discussed. We used a synchronous buck converter operating under a continuous conduction mode condition to determine the load effect and evaluate the model. Results showed that the input port of the fixed-load model and load-variable model had good accuracy up to 70 MHz. We also predicted the load effect on input port noise and found that the input port noise of an 8.2-Ω load could be predicted from the other two load values (6.6 Ω and 11.6 Ω).

We propose high bandwidth and low-cost multichannel power over coaxial (PoC) filter configurations for an automotive LVDS interconnect. To enhance the bandwidth of PoC filters toward a higher frequency range, we have designed a small filter pattern on the PoC filter electrodes and demonstrated a filter property improvement of about 5 dB at 10 GHz without degradation of the insertion loss of the signal line in a simulation. We have also designed a multi-channel PoC filter configuration with fewer components and a smaller mounting area and demonstrated sufficient filter performance in a simulation. These structures were fabricated on test boards and demonstrated by measurement.

We propose a direction-of-arrival (DOA) estimation method for Sound Event Localization and Detection (SELD). Direct estimation of DOA using a deep neural network (DNN), i.e. completely-datadriven approach, achieves high accuracy. However, there is a gap in the accuracy between DOA estimation for single and overlapping sources because they cannot incorporate physical knowledge. Meanwhile, although the accuracy of physics-based approaches is inferior to DNN-based approaches, it is robust for overlapping source. In this study, we consider a combination of physics-based and DNN-based approaches; the sound intensity vectors (IVs) for physics-based DOA estimation is refined based on DNN-based denoising and source separation. This method enables the accurate DOA estimation for both single and overlapping sources using a spherical microphone array. Experimental results show that the proposed method achieves state-of-the-art DOA estimation accuracy on an open dataset of the SELD., Comment: 5 pages, 3 figures, to appear in IEEE ICASSP 2020

We propose a similarity function for one-shot anomaly detection in sounds (ADS) called SPecific anomaly IDentifiER network (SPI- DERnet). In ADS systems, since overlooking an anomaly may re- sult in serious incidents, we need to update such systems using an (often only one) overlooked anomalous sample. A previous study proposed the use of memory-based one-shot learning. A problem with this previous method is that it can detect only short anomalous sounds such as collision sounds because its similarity function is based on a naive mean-squared-error between the input and memo- rized spectrogram. To detect various anomalous sounds, SPIDERnet consists of (i) a neural network-based feature extractor for measur- ing similarity in embedded space and (ii) attention mechanisms for absorbing time-frequency stretching. Experimental results on two public datasets indicate that SPIDERnet outperforms conventional methods and robustly detects various anomalous sounds.

We design a temporary optical coupler to obtain high injection and extraction efficiencies while keeping the bending loss low with the aim of realizing optical cable re-routing without service interruption. The temporary optical coupler injects/extracts signal lights into/from a fiber by using fiber bending. The extraction efficiency is improved by using a double-clad fiber or a graded-index fiber for light injection and extraction while the injection efficiency is maintained compared with that of a conventional temporary optical coupler that uses a single-mode fiber. This improvement enables us to realize an optical cable re-routing operation support system that requires no service interruption.