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As interests in air quality monitoring related to environmental pollution and industrial safety increase, demands for gas sensors are rapidly increasing. Among various gas sensor types, the semiconductor metal oxide (SMO)-type sensor has advantages of high sensitivity, low cost, mass production, and small size but suffers from poor selectivity. To solve this problem, electronic nose (e-nose) systems using a gas sensor array and pattern recognition are widely used. However, as the number of sensors in the e-nose system increases, total power consumption also increases. In this study, an ultra-low-power e-nose system was developed using ultraviolet (UV) micro-LED (μLED) gas sensors and a convolutional neural network (CNN). A monolithic photoactivated gas sensor was developed by depositing a nanocolumnar In

This article introduces a sensorless model predictive control (MPC) scheme for a grid-connected inverter with an inductive–capacitive–inductive ( LCL ) filter using only the grid-side current measurement. A state estimator and a disturbance observer are designed based on the Lyapunov stability theory to reduce the number of sensors and to eliminate the steady-state error. A cost function penalizing the state tracking error is used for the MPC design, and the optimal weights of the cost function are systematically obtained by solving a linear matrix inequality (LMI)-based optimization problem. The variation in grid impedance is taken into account in the LMI optimization. The stability analysis of the overall system is presented, and the frequency responses of the closed-loop and open-loop systems are presented to verify suppression of the filter resonance frequency component. The effectiveness and feasibility of the proposed controller are validated through frequency response analysis and comparative simulation results. Experimental results are also presented to demonstrate the efficacy of the proposed control scheme compared to the linear quadratic regulator method.

III-Nitride semiconductor-based quantum dots (QDs) play an essential role in solid-state quantum light sources because of their potential for room-temperature operation. However, undesired background emission from the surroundings deteriorates single-photon purity. Moreover, spectral diffusion causes inhomogeneous broadening and limits the applications of QDs in quantum photonic technologies. To overcome these obstacles, it is demonstrated that directly pumping carriers to the excited state of the QD reduces the number of carriers generated in the vicinities. The polarization-controlled quasi-resonant excitation is applied to InGaN QDs embedded in GaN nanowire. To analyze the different excitation mechanisms, polarization-resolved absorptions are investigated under the above-barrier bandgap, below-barrier bandgap, and quasi-resonant excitation conditions. By employing polarization-controlled quasi-resonant excitation, the linewidth is reduced from 353 to 272 µeV, and the second-order correlation value is improved from 0.470 to 0.231. Therefore, a greater single-photon purity can be obtained at higher temperatures due to decreased linewidth and background emission.

Parity–time reversal symmetry (PT symmetry) in non-Hermitian systems realizes spontaneous symmetry breaking, thereby leading to counterintuitive phenomena. A coupled system with antisymmetric gain/loss profiles is required to introduce PT symmetry into photonics. As photons are intrinsically non-interactive, selection of two-photonic components is inevitable to mediate indirect coupling via near-fields. Remarkably, exciton–polaritons (the hybrid nature of excitons and photons) are directly interactive via excitonic components; however, the features of direct coupling between exciton–polariton modes have not been investigated so far. Here we demonstrate that such direct coupling can remodel conventional photonic platforms of non-Hermitian systems into polaritonic platforms with a single component; thus improving the degrees of freedom of both integration and design for the coupled system. We focused on the sixfold-symmetric microcavity to exploit degenerated photonic modes. By employing direct coupling with loss modulation, we observed room-temperature polaritonic PT symmetry with a phase transition from unbroken to broken, revealing the lowest threshold of polariton condensates in non-Hermitian degeneracies despite increasing loss. Researchers coupled exciton–polariton modes to one another in a six-fold symmetric microcavity with loss manipulation and observed room-temperature polaritonic parity-time-reversal symmetry.

Models of the protostellar source, B335, are developed using axisymmetric three-dimensional models to resolve conflicts found in one-dimensional models. The models are constrained by a large number of observations, including ALMA, Herschel, and Spitzer data. Observations of the protostellar source B335 with ALMA show red-shifted absorption against a central continuum source indicative of infall in the HCO$^+$ and HCN $J = 4\rightarrow 3$ transitions. The data are combined with a new estimate of the distance to provide strong constraints to three-dimensional radiative transfer models including a rotating, infalling envelope, outflow cavities, and a very small disk. The models favor ages since the initiation of collapse between $3 \times 10^4$ and $4 \times 10^4$ yr for both the continuum and the lines, resolving a conflict found in one-dimensional models. The models under-predict the continuum emission seen by ALMA, suggesting an additional component such as a pseudo-disk. The best-fitting model is used to convert variations in the 4.5 $\mu m$ flux in recent years into a model for a variation of a factor of 5-7 in luminosity over the last 8 years., Comment: 22 pages, 20 figures, in press ApJ

A capacitive electrocardiogram (cECG) signal is considered a promising alternative to a conventional contact electrocardiogram (ECG) signal because the cECG signal can serve the same purpose as the contact ECG signal but can be measured during daily life without causing a subject to feel uncomfortable. However, the cECG signal has a limitation in that detection of QRS complexes, which is a fundamental step to analyze heart condition, is not easy. That is because the cECG signal is sensitive to noise, especially motion noise. This paper proposes a method to detect QRS complexes in cECG signals degraded by motion noise. The proposed method is based on fully convolutional networks (FCNs) and mainly consists of three parts: the generation of ground-truth data, the FCN model, and postprocessing. A labeling process for generating the ground-truth data is proposed. Then, an FCN model that is suitable for cECG signals is proposed. The proposed FCN model uses filters of a large size to achieve a large receptive field, unlike the common FCN models used in image processing. The receptive field is sufficiently large to involve information about adjacent QRS complexes, such as the time interval between the QRS complexes and its variability. By considering the information, the proposed FCN model can reliably classify QRS complexes even in cECG signals degraded by motion noise. Additionally, postprocessing, which consists of an accumulation step and a non-maximum suppression step, is proposed to complement the proposed FCN model. In experiments with real data, the proposed method showed an average sensitivity of 96.94%, positive predictive value of 99.13%, and F1 score of 98.02%. These results demonstrate that the proposed method overcomes the limitation of a cECG signal and helps the cECG signal be widely utilized for medical or healthcare applications.

Epitaxially grown quantum dots (QDs), especially embedded in photonic structures, play an essential role in various quantum photonic systems as on-demand single-photon sources. However, these QDs often suffer from adjacent unwanted emitters, which contribute to the background noise of the QD emission and fundamentally limit the single-photon purity. In this paper, a nanoscale focus pinspot (NFP) technique using focused-ion-beam-induced luminescence quenching enables us to improve single-photon purity from site-controlled QD as a proof-of-concept experiment. The optical quality of the QD emission is not degraded while the signal-to-noise ratio of the QD is improved. Moreover, the QD after the NFP technique reveals the single-photon nature at further elevated temperatures owing to the reduced background noise. As the NFP technique is nondestructive, it retains the apparent physical structures and photonic functions, thereby indicating its promising potential for applying diverse high-purity quantum emitters, particularly integrated in photonic devices and circuits.

We have obtained sensitive dust continuum polarization observations at 850 μm in the B213 region of Taurus using POL-2 on SCUBA-2 at the James Clerk Maxwell Telescope as part of the B-fields in STar-forming Region Observations (BISTRO) survey. These observations allow us to probe magnetic field (B-field) at high spatial resolution (∼2000 au or ∼0.01 pc at 140 pc) in two protostellar cores (K04166 and K04169) and one prestellar core (Miz-8b) that lie within the B213 filament. Using the Davis–Chandrasekhar–Fermi method, we estimate the B-field strengths in K04166, K04169, and Miz-8b to be 38 ± 14, 44 ± 16, and 12 ± 5 μG, respectively. These cores show distinct mean B-field orientations. The B-field in K04166 is well ordered and aligned parallel to the orientations of the core minor axis, outflows, core rotation axis, and large-scale uniform B-field, in accordance with magnetically regulated star formation via ambipolar diffusion taking place in K04166. The B-field in K04169 is found to be ordered but oriented nearly perpendicular to the core minor axis and large-scale B-field and not well correlated with other axes. In contrast, Miz-8b exhibits a disordered B-field that shows no preferred alignment with the core minor axis or large-scale field. We found that only one core, K04166, retains a memory of the large-scale uniform B-field. The other two cores, K04169 and Miz-8b, are decoupled from the large-scale field. Such a complex B-field configuration could be caused by gas inflow onto the filament, even in the presence of a substantial magnetic flux.

A balancing scheme for phase current and voltage of the flying capacitor in a fully integrated multi-level multi-phase DC-DC converter is proposed. The proposed balancing scheme based on the ripple voltage of the flying capacitor can simultaneously mitigate the imbalance of phase current and voltage of the flying capacitor. A mathematical analysis shows the proposed scheme can obtain the current information of the flying capacitor during charging and discharging operations and finally obtain the average inductor-current value. A prototype 4-phase 350 MHz three-level DC-DC converter shows

To overcome the reliability issue of phase-change memory, the development of stable phase-change materials is extremely important. In this study, we analyze 13 dopants for Ge2Sb2Te5 (GST) based on two criteria: i) the change in thermal stability by doping and ii) a lattice distortion. After doping the elements, 11 elements showed a negative doping formation energy compared with pure GST. The angular distortion of the Zn dopant is the largest. The hole carrier decreases, and the electrical resistance increases through Zn-doping in GST. The increased resistance of the material can lead to low power consumption with a high energy effectiveness.

In order to be able to control the phase transition of engineered phase-change materials, the specific understanding of phase transition processes is essential. To understand the effect of dopant o...

This paper proposes a model predictive control (MPC) method using a robust disturbance observer to control the current output of a grid-connected inverter. Firstly, the parameter uncertainties are expressed as possible ranges of resistor, inductor and capacitor values. Secondly, a robust disturbance observer is designed to estimate the lumped disturbance term caused by model uncertainties and the grid voltage disturbance. In addition, the disturbance observer gain, and a weight matrix of the MPC cost function are obtained by applying the Linear matrix inequality (LMI) optimization method. Thirdly, a reference state, which satisfies the control objective of the currents output regulation are derived. Finally, the effectiveness of the proposed MPC method is proven by simulation result.

The application of nanoelectromechanical (NEM) memory switches to memory cell has been proposed. This memory cell has a nonvolatile property. The memory cell can be designed by using one NEM device and four transistors. The area of the memory array using the proposed cell can be reduced compared to conventional SRAM because metal interconnect layers are used for memory storage. Though the writing speed is slower than the conventional memory due to the mechanical beam movement to store data. However, it provides fast reading and nonvolatile property.

Ten protostellar outflows in the Orion molecular clouds were mapped in the $^{12}$CO/$^{13}$CO ${J=6\rightarrow5}$ and $^{12}$CO ${J=7\rightarrow6}$ lines. The maps of these mid-$J$ CO lines have an angular resolution of about 10$''$ and a typical field size of about 100$''$. Physical parameters of the molecular outflows were derived, including mass transfer rates, kinetic luminosities, and outflow forces. The outflow sample was expanded by re-analyzing archival data of nearby low-luminosity protostars, to cover a wide range of bolometric luminosities. Outflow parameters derived from other transitions of CO were compared. The mid-$J$ ($J_{\rm up} \approx 6$) and low-$J$ ($J_{\rm up} \leq 3$) CO line wings trace essentially the same outflow component. By contrast, the high-$J$ (up to $J_{\rm up} \approx 50$) line-emission luminosity of CO shows little correlation with the kinetic luminosity from the ${J=6\rightarrow5}$ line, which suggests that they trace distinct components. The low/mid-$J$ CO line wings trace long-term outflow behaviors while the high-$J$ CO lines are sensitive to short-term activities. The correlations between the outflow parameters and protostellar properties are presented, which shows that the strengths of molecular outflows increase with bolometric luminosity and envelope mass., Comment: 31 pages, 16 figures, Accepted for publication in ApJS

We have used the Taeduk Radio Astronomy Observatory to observe the Orion A and Ophiuchus clouds in the $J=$1$-$0 lines of $^{13}$CO, C$^{18}$O, HCN, HCO$^+$, and N$_2$H$^+$ and the $J=$2$-$1 line of CS. The fully sampled maps with uniform noise levels are used to create moment maps. The variations of the line intensity and velocity dispersion with total column density, derived from dust emission maps, are presented and compared to previous work. The CS line traces dust column density over more than one order of magnitude, and the N$_2$H$^+$ line best traces the highest column density regime ($\log(N_\mathrm{H_2}$) $>$ 22.8). Line luminosities, integrated over the cloud, are compared to those seen in other galaxies. The HCO$^+$-to-HCN luminosity ratio in the Orion A cloud is similar to that of starburst galaxies, while that in the Ophiuchus cloud is in between those of active galactic nuclei and starburst galaxies., 62 pages, 53 figures, 6 tables, accepted for publication in ApJS

Demand for DC-DC voltage conversion from a 48V input has been on the rise due to proliferation of server and automotive applications with a 48V intermediate bus and 48V batteries, respectively. Compared to a 12V, the 48V architecture reduces the power loss thanks to the low distribution losses in the power delivery network. However, improving efficiency is a major challenge in the design of a 48V point-of-load (PoL) DC-DC converter due to the high step-down ratio and high output current. To improve conversion efficiency, several 48V PoL converters implemented with high-quality GaN transistors have been proposed [1], [3]. However, the non-isolated hybrid converter in [1] shows a moderate peak efficiency of 90.9% and requires a large number of switches and passive elements. The isolated converter in [2] shows high efficiency and maximum output current of 80A, requiring a high conversion-ratio planar transformer of 40:1, many switches, and a complicated controller, but offers a limited conversion range. In addition, the GaN transistor suffers from reliability issues [4]. Although an active-clamp forward converter in [5] is implemented with MOSFETs, the peak efficiency is limited to 89.5%. A half-bridge (HB) DC-DC converter with a current-doubler rectifier in [3] is a well-known architecture for high step-down ratio and high output current applications. However, the switching loss in the primary-side HB topology limits the overall efficiency. This paper presents a high-efficiency 3-level HB DC-DC converter with a current-doubler rectifier for power conversion from a 48-to-60V input to an output ranging from 0.5V to 1V.

We present the results of a single-pointing survey of 207 dense cores embedded in Planck Galactic Cold Clumps distributed in five different environments ($\lambda$ Orionis, Orion A, B, Galactic plane, and high latitudes) to identify dense cores on the verge of star formation for the study of the initial conditions of star formation. We observed these cores in eight molecular lines at 76-94 GHz using the Nobeyama 45-m telescope. We find that early-type molecules (e.g., CCS) have low detection rates and that late-type molecules (e.g., N$_2$H$^+$, c-C$_3$H$_2$) and deuterated molecules (e.g., N$_2$D$^+$, DNC) have high detection rates, suggesting that most of the cores are chemically evolved. The deuterium fraction (D/H) is found to decrease with increasing distance, indicating that it suffers from differential beam dilution between the D/H pair of lines for distant cores ($>$1 kpc). For $\lambda$ Orionis, Orion A, and B located at similar distances, D/H is not significantly different, suggesting that there is no systematic difference in the observed chemical properties among these three regions. We identify at least eight high D/H cores in the Orion region and two at high latitudes, which are most likely to be close to the onset of star formation. There is no clear evidence of the evolutionary change in turbulence during the starless phase, suggesting that the dissipation of turbulence is not a major mechanism for the beginning of star formation as judged from observations with a beam size of 0.04 pc., Comment: 55 pages, 12 Figures, 8 Tables, accepted for publication in ApJS

[Abridged] Filaments and hubs have received special attention recently thanks to studies showing their role in star formation. While the column density and velocity structures of both filaments and hubs have been studied, their magnetic fields (B-field) are not yet characterized. We aim to understand the role of the B-field in the dynamical evolution of the NGC 6334 hub-filament network. We present new observations of the dust polarized emission at 850$\mu$m towards NGC 6334 obtained with the JCMT/POL-2. We study the distribution and dispersion of the polarized intensity ($PI$), the polarization fraction ($PF$), and the B-field angle ($\theta_{B}$). We derive the power spectrum of the intensity and $\theta_{B}$ along the ridge crest. Our analyses show a complex B-field structure when observed over the whole region ($\sim10$ pc), however, at smaller scales ($\sim1$ pc), $\theta_{B}$ varies coherently along the filaments. The observed power spectrum of $\theta_{B}$ can be well represented with a power law function with a slope $-1.33\pm0.23$, which is $\sim20\%$ shallower than that of $I$. This result is compatible with the properties of simulated filaments and may indicate the processes at play in the formation of filaments. $\theta_{B}$ rotates from being mostly perpendicular to the filament crests to mostly parallel as they merge with the hubs. This variation of $\theta_{B}$ may be tracing local velocity flows of matter in-falling onto the hubs. Our analysis suggests a variation of the energy balance along the crests of these filaments, from magnetically critical/supercritical at their far ends to magnetically subcritical near the hubs. We detect an increase of $PF$ towards the high-column density star cluster-forming hubs that may result from the increase of grain alignment efficiency due to stellar radiation from the newborn stars., Comment: Accepted for publication in Astronomy & Astrophysics

An efficient, and metal-free approach for the ʟ-proline mediated synthesis of nitrones from nitrosobenzene and benzaldehydes has been established. The reaction undergoes very efficiently at room temperature in methanol as a solvent. The reaction is assumed to involve that the initial formation of azomethine ylide and [2 + 3] cycloaddition of nitrosobenzene, followed by the subsequent retro [2 + 3] cycloaddition could offer the desired nitrone.

This paper proposes a wearable device-based system to monitor the abnormal conditions of a driver, including stress, fatigue, and drowsiness. The system measures the motional and physiological information of the driver using the developed wearable device on the wrist. Preprocessing is used to distinguish the valid signal parts of the measured signals, because various noises can occur in wearable sensors. Features are extracted from the signal parts, and an optimal feature set is determined by an analysis of variance and a sequential floating forward selection algorithm. To classify the driver’s state, a support vector machine-based classification method is used to obtain high generalization performance considering interdriver variance. Experiments were conducted on an indoor driving simulator, with 28 subjects, to gather data for each state. The classification accuracy was 98.43% for fivefold cross validation on the data. In a subject-independent test, the accuracy was 68.31% for the four states and 84.46% for the three states consisting of normal, stressed, and fatigued or drowsy states. Using the proposed system, the abnormal conditions of the driver can be detected and distinguished. This advantage contributes to safer and more comfortable driving. Furthermore, the utilization of the wearable device makes the system easy to use.

A metal-free, one-pot synthesis of 1,2-naphthoquinone was accomplished from 2-naphthol by utilizing economically cheap NBS under open air conditions. Initial formation of 1,1-dibromonaphthalen-2-one and subsequent transformation afforded the 1,2-naphthoquinone. This oxidation was completed within 30 min and had broad substrate scope. Moreover, this system tolerated heterocyclic systems and was also applicable to 1,3-dicarbonyl systems. This practical approach with short reaction times, a simple workup, and insensitivity to moisture could override the usage of expensive and hazardous oxidizing and metal reagents.

Indium vacancies in Bi-doped In3SbTe2 (BIST) cause local distortion or and faster phase transition of BIST with good stability. The formation energy of the In vacancy in the BIST is relatively lower compared to that in IST due to triple negative charge state of the In vacancy (V 3− In) and higher concentration of the V 3− In in BIST. The band gap of BIST is substantially reduced with increasing concentrations of the V 3− In and the hole carriers, which results in a higher electrical conductivity. The phase-change memory (PRAM) device fabricated with the BIST shows very fast, stable switching characteristics at lower voltages.

A series of catechol and dioxolane analogs containing thiazole CGA derivatives have been synthesized and evaluated for their inhibitory activity against α-MSH. The inhibitory activity was improved by replacing an α,β-unsaturated carbonyl of previously reported caffeamides with thiazole motif. Surprisingly, compound 7d , one of the derivatives of dioxolane analogs, displayed the most potent inhibitory activity with an IC 50 of 0.90 μM. Further studies on metabolic stability and bioactivation potential were also accomplished.

Semiconductor quantum dots (QDs) integrated with photonic nanowires are one of the representative platforms for high-purity single photonic sources. However, conventional photonic nanowires suffer from severe scattering at the edge owing to the small footprint. For this reason, tapered structures have been adopted to achieve directional emission with minimized scattering, and hence, high light collection efficiency. So far, various tapered structures have been demonstrated by using top-down etching fabrication or catalyst-assisted growth. However, these approaches can induce critical issues for QD integrated photonic devices such as an etching damage, an inclusion of multiple QDs in a wire, a misalignment of QD with respect to the wire axis center, or a contamination of QD by the catalyst. Therefore, developing a catalyst-free, site-controlled growth technique is essential for high-quality tapered nanowire structures. In this work, we propose a site-selectively grown photonic rocket structure, which consists of a pencil-like nanowire and a pyramid acting as a single-mode waveguide and a coupler, respectively. Since this structure is defined by stable crystal facets, the dimensions of the structure, especially its tapering angle, are determined precisely. Most significantly, a single QD can be formed at the apex, deterministically aligned to the axis center of the photonic structure. We analyzed the propagating mode inside the photonic nanowire and pyramid coupler using finite-difference time-domain simulations. This photonic rocket structure produces directional emission owing to the pyramid coupler, resulting in 2.9 (2.0) times larger light collection efficiency with a numerical aperture of 0.3 (0.7), compared to the nanowire structure alone.

In the published article, we presented high-resolution polarimetry data obtained by using JCMT SCUBA-2/POL-2, and compared them with the larger-scale magnetic structure observed by Planck (Planck Collaboration et al. 2020). There was a miscalculation in the analysis of the Planck data for comparison, and the mean position angle of the Planck magnetic field should be corrected from -40° ± 7° to -48° ± 6°. Thus, we replace the descriptions in the published article as follows. In Section 4.2, paragraph 3, the second sentence should read: "The differences between the orientations of IRAS 4A, IRAS 4B, and IRAS 2A are not statistically significant, but they do show significantly different orientations from those of the global B-field observed by Planck (-48° ± 6°; Section 4.1)." In Section 4.1, paragraph 3, the second line should read: "The Planck B-field orientation shows a smoothly and slowly varying field distribution with a position angle of -48° ± 6° in our observed NGC 1333 area." Accordingly, we replace Figures 4, 5, 9, 10, and 17 to reflect the correct Planck data. As described above, this error of modest magnitude is related only to our derivation of the Planck polarization angle, and the JCMT observation results are unaffected. Therefore, all conclusions drawn in the published article are unchanged even after the above correction is applied. The 1 pc scale magnetic field observed by Planck shows a smooth distribution, and the interstellar magnetic field in molecular clouds increases the complexity significantly on the scale of less than 1 pc.

Phase-change materials have been intensively investigated with various materials and methods. Despite of the efforts, the way to design the novel materials is not reported nearly. In this paper, we have provided a computational high throughput screening method to select a suitable doping element incorporated into a new phase change material for low power consumption and very fast switching phase change random access memory (PRAM). In this method, we have calculated density function theory and simulated ab initio molecular behavior of various dopants in In3SbTe2 (IST) phase change material. As a result, the PRAM fabricated with Bi or Y doped IST shows faster set/reset operation than undoped IST and GeSbTe since Bi and Y offer lower power consumption and faster phase transition mechanism at lower melting temperature due to the lower formation energy and larger distortion angle.

Achieving a fast-transient response is a major challenge when designing a switching regulator for a processor. Furthermore, high-frequency operation with small passive devices and robust control with a small area footprint in a CMOS-logic process are essential for integrated digital-system voltage regulators. A 4-phase hysteretic converter [1] has a superior transient response using a 3.3V input voltage. However, the analog control circuit under a low input voltage suffers from limited dynamic range. Although a time-based design [2] minimizes the use of analog circuits, it still requires an accurate analog-to-time converter and exhibits only a moderate transient response time. A buck voltage regulator (VR) with a digital controller has been proposed for modern digital systems [3], [4], since it can take advantage of the advanced digital process. However, with a conventional digital proportional-integral-derivative (PID) controller it is difficult to offer high bandwidth due to the large power and chip area of the PID and the required multi-bit ADC. Thus, an additional circuit, the resistive transient assist (RTA), was proposed [4]. This paper presents an all-digital synthesizable VR using a digitally-adaptive on-time (DAOT) controller implemented in a CMOS logic process to achieve a fast recovery time.

Physiological signals can be utilized to monitor conditions of a driver, but the inter-subject variance of physiological signals can degrade the classification accuracy of the monitoring system. Personalization of the system using the data of a tested subject, called local data, can be a solution, but the acquisition of sufficient local data may not be possible in real situations. Therefore, this paper proposes an effective personalizing method using small-sized local data. The proposed method utilizes a fuzzy support vector machine to allocate higher weight to the local data than to others, and a fuzzy membership is assigned to the training data by analyzing the importance of each datum. Three classification problems for a physiological signal-based driver monitoring system are introduced and utilized to validate the proposed method. The classification accuracy is compared with that of other personalizing methods, and the results show that the proposed method achieves a better accuracy on average, which is 3.46% higher than that of the simple approach using a basic support vector machine, thereby proving its effectiveness. The proposed method can train a personalized classifier with improved accuracy for a tested subject. The advantages of the proposed method can be utilized to develop a practical driver monitoring system.

Deterministic quantum dots (apex-QDs), which are spontaneously formed at the vertex of pyramid structures, are an attractive single-photon source. Herein, we propose the design of apex-QDs coupled to a single-mode optical fiber for directional emission from a quantum dot, followed by optimization of the structural parameters to maximize the extraction efficiency toward the fiber using FDTD simulation. A dielectric layer of SiO2 was inserted between a silver and a quantum dot to minimize the metallic loss and control the distance between them. For this, the optimum layer thicknesses of silver and SiO2 were 100 nm and 240 nm, respectively, achieving 94% light collection downward near 600 nm in wavelength. The proposed structure was then coupled to a tapered optical fiber, achieving 60% of the quantum dot emission. This high collection through an optical fiber was observed for a wide range of emission wavelengths.

A series of 2,3-dihydro- and 5-chloro-2,3-dihydro-naphtho-[1,2-b]furan-2-carboxylic acid N-(substitutedphenyl)amide analogs (1a-k and 2a-i) were designed and synthesized for developing novel naphthofuran scaffolds as anticancer agents and inhibitors of NF-κB activity. Compound 1d, which had a 4'-chloro group on the N-phenyl ring, exhibited inhibitory activity of NF-κB. Compound 2g, which had a 5'-chloro group on the naphthofuran ring and a 3',5'-bistrifluoromethane group on the N-phenyl ring, had the best NF-κB inhibitory activity. In addition, the novel analogs exhibited potent cytotoxicity at low concentrations against HCT-116, NCI-H23, and PC-3 cell lines. The two electron-withdrawing groups, especially at the 3',5'-position on the N-phenyl ring, increased anticancer activity and NF-κB inhibitory activity. However, only 5-chloro-2,3-dihydronaphtho[1,2-b]furan-2-carboxylic N-(3',5'-bis(trifluoromethyl)phenyl)amide (2g) exhibited both outstanding cytotoxicity and NF-κB inhibitory activities. This novel lead scaffold may be helpful for investigation of new anticancer agents by inactivation of NF-κB.

Capacitive electrocardiogram (ECG) sensors have been developed as a non-intrusive measurement to obtain ECG in daily life. However, the sensors are sensitive to motion noise caused by user′s movement so that this paper suggests a novel noise reduction using active noise cancellation (ANC) with multichannel signals. The proposed algorithm can detect reliable QRS interval and conserve its power while noise is reduced outside the interval. As a result, the proposed algorithm achieved more accurate R peak detection of ECG measured in driving situation than single channel ANC. The method will be useful in the filed reducing noise of multichannel biomedical signal.

Detection of fetal QRS complexes in a noninvasive fetal electrocardiogram (NI-FECG) signal is an important task to check fetal conditions and to prevent birth defects. However, the detection is not easy because the NI-FECG signal contains a maternal ECG signal that has greater amplitude than that of a fetal ECG signal. This paper proposes an algorithm to detect the fetal QRS complexes in the NI-FECG signal. The proposed algorithm is based on convolutional neural networks (CNN) and can reliably detect the fetal QRS complexes without separating the maternal ECG signal. To verify the algorithm, NI-FECG data (PhysioNet/computing in cardiology challenge 2013) were used. The proposed algorithm showed the average sensitivity of 89.06 % and positive predictive value of 92.77 %. The proposed algorithm can help to check fetal conditions and to prevent birth defects.

We have investigated the TUKH122 prestellar core in the Orion A cloud using ALMA 3 mm dust continuum, N$_2$H$^+$ ($J=1-0$), and CH$_3$OH ($J_K=2_K-1_K$) molecular line observations. Previous studies showed that TUKH122 is likely on the verge of star formation because the turbulence is almost dissipated and chemically evolved among other starless cores in the Orion A cloud. By combining ALMA 12-m and ACA data, we recover extended emission with a resolution of $\sim5"$ corresponding to 0.01 pc and identify 6 condensations with a mass range of $0.1-0.4$ $M_\odot$ and a radius of $\lesssim0.01$ pc. These condensations are gravitationally bound following a virial analysis and are embedded in the filament including the elongated core with a mass of $\sim29$ $M_\odot$ and a radial density profile of $r^{-1.6}$ derived by {\it Herschel}. The separation of these condensations is $\sim0.035$ pc, consistent with the thermal jeans length at a density of $4.4\times10^5$ cm$^{-3}$. This density is similar to the central part of the core. We also find a tendency that the N$_2$H$^+$ molecule seems to deplete at the dust peak condensation. This condensation may be beginning to collapse because the linewidth becomes broader. Therefore, the fragmentation still occurs in the prestellar core by thermal Jeans instability and multiple stars are formed within the TUKH122 prestellar core. The CH$_3$OH emission shows a large shell-like distribution and surrounds these condensations, suggesting that the CH$_3$OH molecule formed on dust grains is released into gas phase by non-thermal desorption such as photoevaporation caused by cosmic-ray induced UV radiation., Comment: 13 pages, 14 figures, 2 tables, accepted for publication in ApJ

Universal phase-only spatial light modulators (UP-SLMs) are proposed and demonstrated by simulation and experiment. UP-SLMs, which consist of unitarily coupled electrically controllable wave plates, convert the optically anisotropic properties of the paired two wave plates into an effective single isotropic phase plate and can be realized with electrically tunable birefringence materials such as uniaxial liquid crystals (LCs). The universal approaches are applicable to any uniaxial anisotropic materials based cells, any LC cell operation modes and any incident light polarization states. Further the UP-SLMs are experimentally demonstrated even with commercial LCD panels having low geometrical rotational symmetry. These UP-SLMs will play significant roles in wave optics, communications, information displays, digital holography, quantum optics and quantum information technology by harnessing their unique capacity of modulating the only phase of linearly, circularly, elliptically, azimuthally, radially and even randomly polarized light.

This paper proposes a method to monitor driver's movement using capacitive electrocardiogram (ECG) sensors. The sensor measures ECG by sensing voltage changes in our body, and voltage changes according to the movement of the body also can be measured by the sensor. The proposed method uses independent component analysis to decompose the signal component related to the body movement in the measured signals. In experiments, the signal component by the proposed method was compared with a true signal that represents the movement of a driver, and an averaged correlation coefficient value between the two signals was 0.77. The result shows that the proposed method can give information on the movement of a driver using capacitive ECG sensors, and the information can be utilized to various driver's condition monitoring systems.

The optical absorption rates of lateral and vertical chips are compared with the optical power before and after encapsulation to clarify the concomitant changes. The optical power of lateral chip after packaging with phosphor is higher than that of vertical chip. The difference increases with phosphor content. We argue that chip absorption rate is one of the most important factors in LED packaging because significant amount of light from a chip is reintroduced into the chip by backward scattering at phosphors and reflection at encapsulation surface.