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An electronic nose prototype based on the novel temperature‐modulation technique is developed, where the heater voltage changes its amplitude and frequency periodically. The system comprises a sensor analog front end and a digital processing part including a heater voltage generator and a sensor data transmitter, where the digital part was implemented by a field programmable gate array. The fabricated prototype successfully generated the modulated heater waveform and synchronously acquired sensor responses at a sampling rate of 10 kHz. Whereby, sensor responses to the test gases of volatile organic compounds were collected. Gas classification was achieved with an accuracy of 99.6% based on the data obtained by the prototype, demonstrating the promising properties of the prototype as a compact and highly precise electronic nose. [ABSTRACT FROM AUTHOR]

This study proposes an optimization method for temperature modulation in chemiresistor-type gas sensors based on Bayesian optimization (BO), and its applicability was investigated. As voltage for a sensor heater, our previously proposed waveform was employed, and the parameters determining the voltage range were optimized. Employing the Bouldin–Davies index (DBI) as an objective function (OBJ), BO was utilized to minimize the DBI calculated from a feature matrix built from the collected data followed by pre-processing. The sensor responses were measured using five test gases with five concentrations, amounting to 2500 data points per parameter set. After seven trials with four initial parameter sets (ten parameter sets were tested in total), the DBI was successfully reduced from 2.1 to 1.5. The classification accuracy for the test gases based on the support vector machine tends to increase with decreasing the DBI, indicating that the DBI acts as a good OBJ. Additionally, the accuracy itself increased from 85.4% to 93.2% through optimization. The deviation from the tendency that the accuracy increases with decreasing the DBI for some parameter sets was also discussed. Consequently, it was demonstrated that the proposed optimization method based on BO is promising for temperature modulation. [ABSTRACT FROM AUTHOR]

In this paper, we investigate an assist control for a system in which a human and a robot cooperate to transport an object toward a designated position and angle. We consider a situation where the force due to the human to the object cannot be measured directly. In order to tackle this situation, an assist control with a nonlinear disturbance observer is proposed. By using the observer, we estimate the control input due to the human from position and angle of the object. Moreover, we design the control input by the robot to assist the human input based on the estimates by the disturbance observer. The effectiveness of the proposed method is discussed by numerical simulations for the minimum jerk model. [ABSTRACT FROM AUTHOR]

In this paper, we propose an efficient method for human dense avoidance based on a coverage control. Our motivation is to avoid crowding in public facilities such as stations and government offices, and human dense in the current situation of COVID‐19 from system and control theory. In this paper, humans and robots are modeled as heterogeneous and homogeneous agents, respectively, which make decisions based on their local information. We suppose a dense situation caused by the rendezvous among humans due to their own inherent dynamics. As a main result, we propose a coverage control for a distributed movement of multiple humans. We also characterize the stationary point analytically in terms of the gains that describe a strength of the interconnection of the agents, and the centers of the Voronoi regions related to the agents. Moreover, we verify the meaning of the characterization from an engineering viewpoint of the dense avoidance. Finally, we show the efficiency of the method based on a numerical simulation. [ABSTRACT FROM AUTHOR]

Highly precise weak lensing shear measurement is required for statistical weak gravitational lensing analysis such as cosmic shear measurement to achieve stringent constraints on the cosmological parameters. For this purpose, an accurate shape measurement of background galaxies is crucial in which all systematic errors in the measurement should be carefully corrected. One of the main systematic errors comes from the photon Poisson noise, which comes from the sky brightness (noise bias). We investigate how the photon noise biases the shear measurement within the framework of the ERA method, then develop an analytical noise bias correction method evaluated to the second order. We find that the photon noise does not bias cases of Gaussian profile galaxies with no point spread function (PSF). We also develop noise correction with PSF correction, and tested using simulations based on real galaxy images. The simulations show that the noise bias can be reduced to 0.1 per cent for the case of galaxies with signal-to-noise ratio between 5 and 100. [ABSTRACT FROM AUTHOR]

The article presents a study that aims to elucidate the effect of dietary vitamin E deficiency on anxiety-like behavior in juvenile and adult rats. It highlights the importance of vitamin E for mammals that functions as a lipid-soluble antioxidant where its deficiency may result to progressive neurological syndrome ataxia in both humans and animals. Results from behavioral analysis confirm that the deficiency has triggered anxiety due to an elevated corticosterone concentration.

It has been demonstrated that vitamin E deficiency from birth increases anxiety-related behavior using knockout animals with no vitamin E transfer proteins. The current study was undertaken to elucidate the effect of dietary vitamin E deficiency on anxiety-related behavior of rats in different housing conditions. Male Wistar strain rats were divided into two groups during the weaning period and fed a control or vitamin E-deficient diet. All rats were housed in groups (three rats per cage) for 3 weeks. In the fourth week, half of the rats in each dietary treatment were kept in social housing and the other half were kept in individual housing. Before sacrifice, rota-rod and elevated plus-maze (EPM) tests were performed to measure motor coordination and anxiety, respectively. The EPM test revealed that vitamin E-deficient rats spent less time in the open arms and showed more stretch-out posture than the control rats, showing that anxiety increased with dietary vitamin E deficiency. Furthermore, vitamin E deficiency-induced anxiety behavior was observed more prominent in individual housed rats than in social housed rats. On the basis of these results, we conclude that dietary vitamin E deficiency induces anxiety in rats especially under stress of social isolation. © 2009 International Union of Biochemistry and Molecular Biology, Inc. [ABSTRACT FROM AUTHOR]

We present a method for measuring higher-order weak lensing distortions of faint background galaxies, namely the weak gravitational flexion, by fully extending the Kaiser, Squires & Broadhurst method to include higher-order lensing image characteristics (HOLICs) introduced by Okura, Umetsu, & Futamase. Our HOLICs formalism allows accurate measurements of flexion from practical observational data in the presence of non-circular, anisotropic point spread function. We have applied our method to ground-based Subaru observations of the massive galaxy cluster A1689 at a redshift of z = 0.183. From the high-precision measurements of spin-1 first flexion, we obtain a high-resolution mass map in the central region of A1689. The reconstructed mass map shows a bimodal feature in the central 4′ × 4′ region of the cluster. The major, pronounced mass peak is associated with the brightest cluster galaxy and central cluster members, while the secondary peak is associated with a local concentration of bright galaxies. In Fourier space we separate the reconstructed mass distribution into cluster and subhalo components, from which we obtain projected subhalo masses associated with the primary and the secondary peaks to be M1 = (2.2 ± 0.4) × 1013M⊙/h, and M2 = (1.1 ± 0.3) × 1013M⊙/h, respectively. [ABSTRACT FROM AUTHOR]

Highly accurate weak lensing analysis is urgently required for planned cosmic shear observations. For this purpose we have eliminated various systematic noises in the measurement. The point-spread function (PSF) effect is one of them. A perturbative approach for correcting the PSF effect on the observed image ellipticities has been previously employed. Here we propose a new non-perturbative approach for PSF correction that avoids the systematic error associated with the perturbative approach. The new method uses an artificial image for measuring shear which has the same ellipticity as the lensed image. This is done by re-smearing the observed galaxy images and observed star images (PSF) with an additional smearing function to obtain the original lensed galaxy images. We tested the new method with simple simulated objects that have Gaussian or Sérsic profiles smeared by a Gaussian PSF with sufficiently large size to neglect pixelization. Under the condition of no pixel noise, it is confirmed that the new method has no systematic error even if the PSF is large and has a high ellipticity. [ABSTRACT FROM AUTHOR]

A portable electronic nose (e-nose) with miniature size and low-power consumption allows us to utilize the information of smells, greatly contributing to industry and daily life. In order to realize such a miniature and low-power e-nose, acquiring the data including plenty of information of gas species or smells with a reduced number of sensor elements is required. For this issue, this study proposes novel temperature modulation based on heater voltage, which amplitude and frequency periodically change. We first conducted gas discrimination tests based on the data obtained from a single gas sensor. The proposed method enabled to obtain responses under various temperatures and frequencies at one time. Furthermore, the periodical changes in amplitude and frequency caused the hysteresis characteristic to the gas species in the time-dependent response. Based on principal component analysis, we confirmed the improvement in the gas discrimination performance compared with that by conventional temperature modulation with sinusoidal heater voltage. Gas discrimination using machine learning algorithms was also carried out. The discrimination accuracy was revealed to increase with the dimensions of the principal component, reaching 98.8% at the maximum. Consequently, the promising properties of the proposed temperature modulation for obtaining enhanced information of gas species are demonstrated. • Novel temperature modulation inspired by radiocommunication technology was proposed. • Sensor responses including plentiful information of gas species were obtained. • Eight kinds of gases were successfully discriminated by machine learning. [ABSTRACT FROM AUTHOR]

Multi-spectral filter array composed of a wavy alternating dielectric multilayer was integrated on a CMOS image sensor of the Raspberry Pi HQ Camera. The filter array consists of 16-channel elementary filters exhibiting pseudo-random transmission characteristics. Each filter covers 20 × 20 CMOS pixels. The incoming spectrum is encoded as a set of 16 grayscale intensities and passed to principal component analysis (PCA) to classify the states of the target spectral characteristic. Preliminary demonstration for blood flow state identification in human peripheral revealed proposed device's potential ability as a real-time monitoring tool in the near infrared. [ABSTRACT FROM AUTHOR]

We present the launch of the Hyper Suprime-Cam Legacy Archive (HSCLA), a public archive of processed, science-ready data from the Hyper Suprime-Cam (HSC). HSC is an optical wide-field imager installed at the prime focus of the Subaru Telescope and has been in operation since 2014. While ∼1/3 of the total observing time of HSC has been used for the Subaru Strategic Program (SSP), the remainder of the time is used for Principal Investigator (PI)-based programs. We have processed the data from these PI-based programs and make the processed, high-quality data available to the community through HSCLA. The current version of HSCLA includes data taken in the first year of science operation, 2014. We provide both individual and coadd images as well as photometric catalogs. The photometric catalog from the coadd is loaded to the database, which offers a fast access to the large catalog. There are other online tools such as an image browser and an image cutout tool and they will be useful for science analyses. The coadd images reach 24–27th magnitudes at 5σ for point sources and cover approximately 580 square degrees in at least one filter with 150 million objects in total. We perform extensive quality assurance tests and verify that the photometric and astrometric quality of the data is good enough for most scientific explorations. However, the data are not without problems and users are referred to the list of known issues before exploiting the data for science. All the data and documentations can be found at the data release site, 〈 https://hscla.mtk.nao.ac.jp/ 〉. [ABSTRACT FROM AUTHOR]