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This study utilized a sliding mode control (SMC) technique combined with modified exponential reaching law to address the control of a nonlinear system. The introduced adaptive reaching law enables the system trajectories to converge rapidly toward the origin, surpassing the convergence speed achieved by the existing reaching laws. By employing the suggested reaching law, the SMC exhibits remarkable performance while effectively mitigating chattering. Furthermore, the proposed reaching law enables the system trajectories to converge rapidly toward the origin, surpassing the convergence speed achieved by the existing reaching laws. This article includes simulation results and a comparison with other predominantly existing approaches to highlight the superior performance of the proposed reaching law. [ABSTRACT FROM AUTHOR]

The permanent magnet synchronous motor (PMSM) has been of interest to eco-friendly industries on account of its advantages such as high performance, efficiency, and precision control. However, perturbations due to PMSM parameter uncertainty, load torque, and external disturbance interfere with the construction of PMSM precision control systems. Therefore, a robust control system is needed to avoid unnecessary system movement caused by perturbations. In this paper, sliding mode control (SMC) is adopted to implement a robust control system for the PMSM. In order to reduce the reaching time from the initial system state to the sliding surface and the chattering phenomenon that can cause the system to malfunction, the adaptive quick sliding mode reaching law based on an exponential function and power equation is proposed. Although the SMC is robust to disturbance and parameter uncertainty, unexpected disturbances can destabilize the system. To estimate the unmatched disturbance in a short time, the second-order fast terminal sliding mode observer (SFTSMO) is proposed. The results show that the motor control system based on the proposed method has a fast convergence speed to an objective value, position tracking performance, and robustness. [ABSTRACT FROM AUTHOR]

Understanding how the structural organization of neural networks influences their computational capabilities is of great interest to both machine learning and neuroscience communities. In our previous work, we introduced a novel learning system, called the reservoir of basal dynamics (reBASICS), which features a modular neural architecture (small-sized random neural networks) capable of reducing chaoticity of neural activity and of producing stable self-sustained limit cycle activities. The integration of these limit cycles is achieved by linear summation of their weights, and arbitrary time series are learned by modulating these weights. Despite its excellent learning performance, interpreting a modular structure of isolated small networks as a brain network has posed a significant challenge. Here, we investigate how local connectivity, a well-known characteristic of brain networks, contributes to reducing neural system chaoticity and generates self-sustained limit cycles based on empirical experiments. Moreover, we present the learning performance of the locally connected reBASICS in two tasks: a motor timing task and a learning task of the Lorenz time series. Although its performance was inferior to that of modular reBASICS, locally connected reBASICS could learn a time series of tens of seconds while the time constant of neural units was ten milliseconds. This work indicates that the locality of connectivity in neural networks may contribute to generation of stable self-sustained oscillations to learn arbitrary long-term time series, as well as the economy of wiring cost. [ABSTRACT FROM AUTHOR]

First-principles calculations were performed to calculate the electronic structures of low temperature phase (LTP) MnBi (Mn50Bi50) and substitutionally and interstitially Sn-doped MnBi [Mn50Bi25Sn25, (Mn0.5Bi0.5)66.7Sn33.3]. Brillouin function predicts the temperature dependence of saturation magnetization M(T). Sn substitution for Bi in MnBi (Mn50Bi25Sn25) changes the magnetocrystalline anisotropy constant (Ku) from −0.202 MJ/m3 (the in-plane magnetization) for LTP MnBi to 1.711 MJ/m3 (the out-of-plane magnetization). In comparison, the Ku remains negative but slightly decreases to −0.043 MJ/m3 when Sn is interstitially doped in MnBi [(Mn0.5Bi0.5)66.7Sn33.3]. The Curie temperature (TC) decreases from 716 K for LTP Mn50Bi50 to 445 K for Mn50Bi25Sn25 and 285 K for (Mn0.5Bi0.5)66.7Sn33.3. Mn50Bi25Sn25 has a lower magnetic moment of 5.034 μB/f.u. but a higher saturation magnetization of 64.2 emu/g than (Mn0.5Bi0.5)66.7Sn33.3 with a magnetic moment of 6.609 μB/f.u. and a saturation magnetization of 48.2 emu/g because the weight and volume of the substitutionally Sn-doped MnBi are smaller than the interstitially Sn-doped MnBi. The low Curie temperature and magnetization for Sn-doped MnBi are attributed to the high concentration of Sn. Thus, future study needs to focus on low Sn-concentrated MnBi. [ABSTRACT FROM AUTHOR]

Understanding how the structural organization of neural networks influences their computational capabilities is of great interest to both machine learning and neuroscience communities. In our previous work, we introduced a novel learning system, called the reservoir of basal dynamics (reBASICS), which features a modular neural architecture (small-sized random neural networks) capable of reducing chaoticity of neural activity and of producing stable self-sustained limit cycle activities. The integration of these limit cycles is achieved by linear summation of their weights, and arbitrary time series are learned by modulating these weights. Despite its excellent learning performance, interpreting a modular structure of isolated small networks as a brain network has posed a significant challenge. Here, we investigate how local connectivity, a well-known characteristic of brain networks, contributes to reducing neural system chaoticity and generates self-sustained limit cycles based on empirical experiments. Moreover, we present the learning performance of the locally connected reBASICS in two tasks: a motor timing task and a learning task of the Lorenz time series. Although its performance was inferior to that of modular reBASICS, locally connected reBASICS could learn a time series of tens of seconds while the time constant of neural units was ten milliseconds. This work indicates that the locality of connectivity in neural networks may contribute to generation of stable self-sustained oscillations to learn arbitrary long-term time series, as well as the economy of wiring cost. [ABSTRACT FROM AUTHOR]

People tend to expect mental capabilities in a robot based on anthropomorphism and often attribute the cause and responsibility for a failure in human-robot interactions to the robot. This study investigated the relationship between mind perception, a psychological scale of anthropomorphism, and attribution of the cause and responsibility in human-robot interactions. Participants played a repeated noncooperative game with a human, robot, or computer agent, where their monetary rewards depended on the outcome. They completed questionnaires on mind perception regarding the agent and whether the participant's own or the agent's decisions resulted in the unexpectedly small reward. We extracted two factors of Experience (capacity to sense and feel) and Agency (capacity to plan and act) from the mind perception scores. Then, correlation and structural equation modeling (SEM) approaches were used to analyze the data. The findings showed that mind perception influenced attribution processes differently for each agent type. In the human condition, decreased Agency score during the game led to greater causal attribution to the human agent, consequently also increasing the degree of responsibility attribution to the human agent. In the robot condition, the post-game Agency score decreased the degree of causal attribution to the robot, and the post-game Experience score increased the degree of responsibility to the robot. These relationships were not observed in the computer condition. The study highlights the importance of considering mind perception in designing appropriate causal and responsibility attribution in human-robot interactions and developing socially acceptable robots. [ABSTRACT FROM AUTHOR]

Small- and large-scale accidents often occur in workplaces handling hazardous chemical substances. These accidents are usually caused by leaks, explosions, fires and complex chemicals; a large proportion of these chemical accidents are caused by leaks. A chemical release accident that injured four people occurred during an optical film-manufacturing process. This report analyzes the causes of this accident and provides effective measures for accident prevention. This accident was caused by an abnormal reaction during the input of raw materials prior to their heating. Tertiary butyl alcohol (t-BuOH), distilled water (DW), and potassium permanganate (KMnO4) were mainly used in this process. We found that this mixture reacted with unknown impurities. After KMnO4 was added to the mixture of t-BuOH and DW, a large amount of heat was suddenly released from the reactor for one minute. In particular, a small amount of methanol (4%), which could have entered the mixture during the cleaning process, and seal oil containing glycerin (13%) were suspected to be the key materials influencing the rapid reaction. Given the significant findings about this accident, the precautionary technical/administrative measures we provide herein may help prevent such accidents in future. [ABSTRACT FROM AUTHOR]

Objectives Peak exposure to extremely low-frequency magnetic fields (ELF-MF) among semiconductor workers was characterized by type of factory, operation, and job. Methods A portable EMDEX meter was used to monitor the ELF-MF exposure of 117 semiconductor workers who are involved in wafer fabrication (fab) and assembly operations. ELF-MF measurements were logged every 3 s and categorized by process and job or activity during working hours. Two values of 0.5 and 1 μT were adopted subjectively as cutoff values of peak exposure levels based on a literature review. Results All semiconductor workers who were involved in diffusion, ion implanter operation, module, and chip test were exposed to ELF-MF higher than 0.5 μT during their entire working time. Engineers who maintained electric facilities in the semiconductor operations were exposed to the highest ELF-MF peak levels (2.5 μT on average above 0.5 μT and 3.6 μT on average above 1 μT). Operators working in chip testing showed the highest daily contribution of their peak levels to their daily average ELF-MF exposure levels (98.1% and 83.9%). In contrast, chemical mechanical planarization engineers, wafer test operators, and administrative workers outside clean rooms showed average exposure to less than 0.5 μT and a low proportion of duration of time exposed above either the 0.5 μT or 1 μT peak level points, along with a low daily contribution of peak exposure levels (16.0, 11.9, and 18.7%). Conclusions Most of the activities and working locations next to machines generating ELF-MF in semiconductor operations showed high contributions of ELF-MF peak exposure to daily exposure dose despite their relative minor fraction of workers' daily time. [ABSTRACT FROM AUTHOR]

Backscatter communication is a battery-less data transmission method for massive IoT devices. These backscatter devices receive an incident signal from an RF-source gateway to harvest energy. These devices can be operated to transmit data after harvesting energy. This technology is widely applied to smart city applications. In general, IoT devices in the smart city applications have insufficient resources. They use narrowband communication to transmit small sizes of data. Thus, a simple channel access approach should be considered for data transmission. In addition, network scalability is also important in the backscatter network for smart city applications. According to energy harvesting and data generation, devices participating in data transmission can change frequently. Providing the network scalability by the changing devices can improve the transmission efficiency in the backscatter network. Therefore, we propose a novel media access scheme for the backscatter network in the smart city applications. The proposed scheme is designed by the contention-based approach to support the network scalability. It controls backscattering signal for energy harvesting and distributes contention in multiple access. It allows additional data transmission in backscattering period for harvesting energy to provide fairness of devices. For performance evaluation, extensive computer simulations are carried out and the proposed method is compared to TDMA that is a typical media access scheme in the backscatter network. [ABSTRACT FROM AUTHOR]

A conventional energy product calculated by the product of the B-field and the H-field is not sufficient for representing the performance of a magnet because it considers the homogeneous and only the uniaxial magnetic properties of the magnet. The conventional energy product has been compared with another energy product obtained by integrating the scalar product of the B-field and the H-field of each cell composed of the three-dimensional components. We investigated a model system by micromagnetic simulation using finite differential method (FDM) and calculated the full hysteresis of the magnet. The model system of a Nd2Fe14B magnet composed of grains with a diameter of about 100 nm was assumed. In the case of the isotropic multi-grain magnet, the energy product calculated by the integration method was 28% larger than the energy product obtained by the conventional way, although a discrepancy between the distribution of the magnetizations and the demagnetizing fields at the reversal process resulted in the decrease of the energy product. [ABSTRACT FROM AUTHOR]

An increase in power consumption necessitates a low-power circuit technology to extend Moore's law. Low-power transistors, such as tunnel field-effect transistors (TFETs), negative-capacitance field-effect transistors (NC-FETs), and Dirac-source field-effect transistors (DS-FETs), have been realised to break the thermionic limit of the subthreshold swing (SS). However, a low-power rectifier, able to overcome the thermionic limit of an ideality factor (η) of 1 at room temperature, has not been proposed yet. In this study, we have realised a DS diode based on graphene/MoS2/graphite van der Waals heterostructures, which exhibits a steep-slope characteristic curve, by exploiting the linear density of states (DOSs) of graphene. For the developed DS diode, we obtained η < 1 for more than four decades of drain current (ηave_4dec < 1) with a minimum value of 0.8, and a rectifying ratio exceeding 108. The realisation of a DS diode represents an additional step towards the development of low-power electronic circuits. While different types of low-power transistors have been investigated, low voltage rectifiers able to overcome the thermionic limit have not been proposed yet. Here, the authors report the realization of Dirac-source diodes based on graphene/MoS2/graphite heterostructures, showing ideality factors <1 and rectifying ratios exceeding 108 at room temperature. [ABSTRACT FROM AUTHOR]

The integrated gradients (IG) method is widely used to evaluate the extent to which each input feature contributes to the classification using a deep learning model because it theoretically satisfies the desired properties to fairly attribute the contributions to the classification. However, this approach requires an appropriate baseline to do so. In this study, we propose a compensated IG method that does not require a baseline, which compensates the contributions calculated using the IG method at an arbitrary baseline by using an example of the Shapley sampling value. We prove that the proposed approach can compute the contributions to the classification results reliably if the processes of each input feature in a classifier are independent of one another and the parameterization of each process is identical, as in shared weights in convolutional neural networks. Using three datasets on electroencephalogram recordings, we experimentally demonstrate that the contributions obtained by the proposed compensated IG method are more reliable than those obtained using the original IG method and that its computational complexity is much lower than that of the Shapley sampling method. [ABSTRACT FROM AUTHOR]

Today's circuit technology requires low-power transistors and diodes to extend Moore's law. While research has been focused on reducing power consumption of transistors, low-power diodes have not been widely studied. Here, we report a low-power, thus steep-slope Schottky diode, with a "cold metal" source. The Schottky barrier between metal electrode and bulk MoS2 enabled the diode behavior, and the steep-slope diode IV curve originated from the change in the density of states of a graphite (cold metal) source with a bias voltage. The MoS2 Schottky diode with a cold metal exhibits an ideality factor (η) < 1 for more than four decades of drain current with a sizable rectifying ratio (108). The realization of a steep-slope Schottky diode paves the way to the improvement in low-power circuit technology. [ABSTRACT FROM AUTHOR]

We computationally investigate the conformational behavior, "bridging" chain, between different the phase-separated domains vs "looping" chain on the same domain, for two chain architectures of ABA triblock copolymers, one with a linear architecture (L-TBC) and the other with comb architecture (C-TBC) at various segregation regimes using dissipative particle dynamics (DPD) simulations. The power-law relation between the bridge fraction (Φ) and the interaction parameter (χ) for C-TBC is found to be Φ ∼ χ − 1.6 in the vicinity of the order-disorder transition ( χ O D T ), indicating a drastic conversion from the bridge to the loop conformation. When χ further increases, the bridge-loop conversions slow down to have the power law, Φ ∼ χ − 0.18 , approaching the theoretical power law Φ ∼ χ − 1 / 9 predicted in the strong segregation limit. The conformational assessment conducted in the present study can provide a strategy of designing optimal material and processing conditions for triblock copolymer either with linear or comb architecture to be used for thermoplastic elastomer or molecular nanocomposites. [ABSTRACT FROM AUTHOR]

The order-disorder transitions (ODT) of core-shell bottle brush copolymer and its structural isomers were investigated by dissipative particle dynamics simulations and theoretically by random phase approximation. Introducing a chain topology parameter λ which parametrizes linking points between M diblock chains each with N monomers, the degree of incompatibility at ODT ( (χ N) ODT ; χ being the Flory–Huggins interaction parameter between constituent monomers) was predicted as a function of chain topology parameter (λ) and the number of linked diblock chains per bottle brush copolymer (M). It was found that there exists an optimal chain topology about λ at which (χ N) ODT gets a minimum while the domain spacing remains nearly unchanged. The prediction provides a theoretical guideline for designing an optimal copolymer architecture capable of forming sub-10 nm periodic structures even with non-high χ components. [ABSTRACT FROM AUTHOR]

The magnetic properties of ThMn12-type Fe-rich compounds were investigated by producing Sm(Fe0.8Co0.2)10Si2 ribbons. The produced ribbons, with different conditions by varying the melt-spinning conditions, were characterized to investigate physical and magnetic properties. Weight fraction of ThMn12-type phase decreased from 94.5 to 57.1 wt. % as the melt-spinning wheel speed increased from 6.5 to 39 m/s, and corresponding magnetizations and coercivities were substantially varied; the coercivity increased up to 0.175 T from 0.058 T by increasing the wheel speed from 6.5 to 26 m/s, and their magnetization also increased from 89.81 Am2/kg to 105.58 Am2/kg, even though the content of ThMn12-type phase decreased. Morphologies of the ribbons were also observed to verify the melt-spinning effects on the surface conditions and grain sizes. It was found that the particle and grain sizes in the ribbons became smaller and striped patterns appeared as the wheel speed increased. The grain size decreased from about 1 μm to 250 nm by increasing the wheel speed from 6.5 to 39 m/s. [ABSTRACT FROM AUTHOR]

Bladder outlet obstruction (BOO) due to benign prostatic hyperplasia (BPH) is the most common cause of lower urinary tract symptoms (LUTS) in older men. Although medical treatments can reduce BPH-related LUTS and even prevent invasive treatments, at least one in five men who complain of LUTS due to BPH will eventually need surgery. Of LUTS, storage symptoms persist in 20 to 40% of patients even after the obstruction is resolved. The present study aims to investigate the predisposing factors of the persistent storage symptoms after HoLEP in patients with BPH and their correlations to the recovery time of the symptoms. A total of 127 patients with complaints of storage symptoms and who underwent transurethral HoLEP surgery at Pusan National University Hospital from May 2014 to June 2017 were included in this study. Urodynamic studies were performed in all patients, and BOO was confirmed by urodynamic studies before HoLEP. All patients were asked to complete the IPSS (also known as the American Urological Association score) and the Overactive Bladder Symptom Score (OABSS) questionnaire to evaluate LUTS on the day before HoLEP and 3 months after HoLEP. Patients were divided into group I, which included patients with persistent storage symptoms after HoLEP, and group II, which included patients without storage symptoms after HoLEP. Of a total of 127 patients, 68 were included in group I, and the remaining 59 were included in group II. In the univariable analysis, group I showed statistically significantly older mean age, higher mean peak detrusor pressure during filling cystometry, and lower mean MCC than group II. Multivariate analysis of these three variables showed that only mean age and mean peak detrusor pressure during filling cystometry had statistically significant differences. In group I, 12 patients had storage symptoms until 12 months after surgery. When comparing these patients with the remaining 56 patients, only mean age showed statistically significant differences. Old age and high peak detrusor pressure during filling cystometry were the predictors of persistent storage symptoms after HoLEP. Furthermore, older patients were unlikely to recover storage symptoms until 12 months after operation. [ABSTRACT FROM AUTHOR]

We calculate the electronic structures of FePt and Fe0.5Mn0.5Pt using first-principles calculations based on density functional theory within the local-spin-density approximation. The Curie temperature (Tc) was calculated by mean field approximation. Composition dependence of the Cure temperature (Tc(x)) of Fe1-xMnxPt was used to identify a composition to meet the desired Tc in the range of 600-650K. The identified composition (0.0294≤x≤0.0713) gives saturation magnetization (Ms) in the range of 1041-919 emu/cm3 and magnetocrystalline anisotropy constant (K) in the range of 9.96-8.36 × 106 J/m3 at 0 K. Temperature dependent M(T) and K(T) of Fe1-xMnxPt (0.0294≤ x ≤ 0.0713) were calculated using the Brillouin function and Callen-Callen experimental relation, respectively. Fe1-xMnxPt (0.0294≤ x ≤0.0713) shows 930-800 emu/cm3 of Ms and 7.18-5.61 × 106 J/m3 of K at 300K, thereby satisfying desired magnetic properties for heat-assisted magnetic recording media to achieve 4 Tb/in.2 areal density. [ABSTRACT FROM AUTHOR]

Although epidural patient-controlled analgesia (PCA) to control postoperative pain after total knee arthroplasty (TKA), the relationship of epidural PCA with postoperative bleeding remains controversial. Therefore, we aimed to evaluate the effect of epidural and intravenous PCA on postoperative bleeding in patients undergoing unilateral TKA. Total of 2467 patients who underwent TKA were divided to intravenous PCA (n = 2339) or epidural PCA (n = 128) group. After 1:1 propensity score-matching, 212 patients were analyzed to assess the associations between the perioperative blood loss and epidural PCA between the groups. Mean postoperative blood loss was significantly greater in epidural PCA than in intravenous PCA (900.9 ± 369.1 mL vs. 737.8 ± 410.1 mL; P = 0.007). The incidence of red blood cell (RBC) administration (> 3 units) was significantly higher in epidural PCA than in intravenous PCA (30.2% vs. 16.0%; OR 2.5; 95% CI 1.201–5.205; P = 0.014). Epidural PCA may be strongly related to postoperative bleeding and the incidence of RBC transfusion of more than 3 units after unilateral TKA, as compared to intravenous PCA. Therefore, the use of epidural PCA may be carefully considered for postoperative pain management in TKA. [ABSTRACT FROM AUTHOR]

Harmful emissions including particulates, volatile organic compounds, and aldehydes are generated during three‐dimensional (3D) printing. Ultrafine particles are particularly important due to their ability to penetrate deep into the lung. We modeled inhalation exposure by particle size during 3D printing. A total of six thermoplastic filaments were used for printing under manufacturer's recommended conditions, and particle emissions in the size range between 10 nm and 10 μm were measured. The inhalation exposure dose including inhaled and deposited doses was estimated using a mathematical model. For all materials, the number of particles between 10 nm and 1 μm accounted for a large proportion among the released particles, with nano‐sized particles being the dominant size. More than 1.3 × 109 nano‐sized particles/kgbw/g (95.3 ± 104.0 ng/kgbw/g) could be inhaled, and a considerable amount was deposited in respiratory regions. The total deposited dose in terms of particle number was 3.1 × 108 particles/kgbw/g (63.6% of the total inhaled dose), and most (41.3%) were deposited in the alveolar region. The total mass of particles deposited was 19.8 ± 16.6 ng/kgbw/g, with 10.1% of the total mass deposited in the alveolar region. Given our findings, the inhalation exposure level is mainly determined by printing conditions, particularly the filament type and manufacturer‐recommended extruder temperature. [ABSTRACT FROM AUTHOR]

In this study, the applicability of the composite model for assessing seawater intrusion and soil salinization in coastal aquifers due to climate change was investigated. In this approach, flow in the saturated zone of a coastal aquifer is simulated using a three-dimensional saturated–unsaturated transport model and flow in the unsaturated zone between the surface and groundwater level is simulated using a one-dimensional model in the vertical direction. Long-term sea-level predictions obtained using the representative concentration pathway (RCP) 4.5 and 8.5 scenarios were applied for computing the sea-level rise for 91 country-managed reclaimed areas in the Republic of Korea. Composite results were obtained and analyzed for seawater intrusion and soil salinization due to sea-level rise. In the results of groundwater and soil salinity in all 91 reclaimed land, the increasing rate of groundwater and soil salinity in the RCP 4.5 scenario was 13.5% and 10.4%, respectively. In the RCP 8.5 scenario, the increasing rate of groundwater and soil salinity was 14.1% and 11.1%, respectively. The groundwater level increased to 0.41 m in the RCP 4.5 scenario and 0.51 m in the RCP 8.5 scenario. The results for two representative reclaimed land areas in the Heungwang and Deokchon districts were examined in detail. The composite analysis revealed that widespread damage could be caused by sea-level rise in the reclaimed land and that seawater intrusion in many regions will accelerate groundwater salinization over time. Moreover, the reclaimed land areas were characterized in terms of watershed size, presence of ponds, water levels of the ponds, and pond locations. In reclaimed land located in small watersheds, the groundwater recharge area was smaller than in land located in larger watershed areas. Consequently, the seawater in small watersheds penetrated further inland. Ponds with water levels higher than the sea level effectively prevented seawater intrusion into groundwater. If the water level of a pond is similar to or lower than the sea level, it indicates that seawater has already penetrated a large part of the aquifer. The composite model developed in this study seems to be one of the simulation methods that can be applied when simulating saturated and unsaturated zone to a large number of sites. Also, the study results could be used to establish and implement a long-term comprehensive plan for water resources at the national level, considering seawater intrusion due to climate change and providing a basis for establishing countermeasures against future seawater intrusion. [ABSTRACT FROM AUTHOR]

This article presents a 320 $\times $ 240 indirect time-of-flight (iToF) CMOS image sensor (CIS) with on-chip motion artifact suppression and background light cancelling (BGLC). The proposed iToF CIS uses a backside-illuminated trident pinned photodiode (PPD) that assists charge transfer with a built-in lateral electric field for enhanced depth accuracy. To overcome the limitation of the conventional iToF CIS that exhibits motion artifact, we propose a pseudo-four-tap (P4-tap) demodulation method with alternate phase driving using a conventional two-tap pixel structure with a high fill factor of over 43%. In addition, by combining the advantages of both the P4-tap and conventional two-tap demodulation schemes, we propose hybrid depth imaging with reduced motion artifact for moving objects, while providing high-depth precision for the static background. For outdoor mobile applications of the iToF CIS, we integrated on-chip BGLC circuits to eliminate the BGL-induced depth error. A prototype chip is fabricated using a 90-nm backside illumination (BSI) CIS process. The BSI trident PPD enabled a low depth error of under 0.54% over the range of 0.75–4 m, with a modulation frequency of 100 MHz. Motion artifact was suppressed at 60 frames/s of hybrid depth imaging owing to the proposed P4-tap scheme. With the on-chip BGLC circuit, the experimental results demonstrate a 0.55% depth error at a 1-m distance, even under 120-klx BGL illumination. [ABSTRACT FROM AUTHOR]

Paddy fields play a critical role as storage for the retention of surface water in hydrological processes, but their water balance is complicated by irrigation and drainage management. Studies have proposed flow routing methods for paddy fields by simplifying the hydrological and hydraulic complexity associated with drainage processes. However, the performance of paddy field routing schemes has not yet been sufficiently evaluated to assist in the selection of routing methods for a water balance analysis. This study evaluated three common drainage routing schemes developed for paddy fields, including the simple water balance (SWB), linear reservoir with threshold (LRT), and broad-crested weir (BCW) models, in terms of complexity and performance. This study also compared the accuracy of irrigation water requirement and sediment load estimates simulated using the three schemes. Results showed that the BCW model produced the best statistical accuracy when predicting daily flow, but the three routing methods performed similarly over a 10-day time scale. Results suggested that the simple structure of the SWB model was not accurate enough to reproduce high and low flow on a daily scale, which produced relatively higher irrigation water requirements and sediment loads compared with those of LRT and BCW. LRT provided performance statistics similar to those of BCW using fewer calibration parameters. The comparison confirmed a trade-off relationship between model complexity and performance, highlighting the importance of model selection for hydrological analysis. [ABSTRACT FROM AUTHOR]

Physicochemical properties between colloidal engineered nanomaterials (ENMs) and aerosols released from consumer spray products were characterized. A dynamic light scattering (DLS), transmission electron microscopy (TEM), and inductively coupled plasma mass spectrometer (ICP‐MS) were used to evaluate the suspended ENMs in the products. Direct‐reading instruments, TEM, and ICP‐MS were used to characterize the properties of aerosolized ENMs. The aerosolized organic compounds with ENMs were assumed to be vaporized for a short time after spraying. The median diameter of ENMs in product solutions measured by DLS was about 200‐350 nm, while individual particle was confirmed from 3 to 50 nm by TEM. The size of aerosolized ENMs was ranged from 7 to 44 nm, and their aggregates were about 100‐1000 nm in near distance. Some inorganic substances including raw nanomaterials were also found in the aerosol. The particles released from the propellant sprays were identified in far distance, while they were not found in far distance when pump sprays were used. The number concentration from the propellant sprays increased up to 6000 particles/cm3/g at near distance and dispersed to far distance, while the most of droplets emitted from pump sprays were settled down near sprayer's location. We found other metals besides labeled ENMs are included in each product and the characteristics of the particles are different when they are sprayed. [ABSTRACT FROM AUTHOR]

This work presents self-focusing 3D lithography based on the refractive index changes of polyethylene glycol diacrylate (PEGDA) during photopolymerization. Since the polymerization of PEGDA leads to an increase in the refractive index, the UV light rays in the PEGDA undergo a refraction effect during exposure, thus being focused and forming 3D photopolymerized structures. We demonstrate the potential of self-focusing 3D lithography by fabricating PEGDA microneedles and trapezoid-shaped microwells. Their structures well match our theoretical estimation. Therefore, our theoretical approach can provide a short route to realizing on-demand, complicated 3D structures of refractive-index-variable materials with single UV exposure. [ABSTRACT FROM AUTHOR]

Background: Intramuscular dexmedetomidine can be used for pediatric sedation without requiring intravenous access and has advantages for electroencephalography by inducing natural sleep pathway, but only a limited number of studies compared the efficacy of intramuscular dexmedetomidine with oral chloral hydrate. Aims: To compare the efficacy and safety of intramuscular dexmedetomidine and oral chloral hydrate used for sedation during electroencephalography in pediatric patients. Methods: We reviewed the medical records of pediatric patients who underwent sedation for electroencephalography between January 2015 and December 2016. Initial doses of dexmedetomidine and chloral hydrate were 3 mcg/kg and 50 mg/kg, respectively; second doses (1 mcg/kg and 50 mg/kg, respectively) were administered if adequate sedation was not achieved. Demographic data, time of sedative administration, time of sedation and awakening, and time of arrival at recovery room and discharge were analyzed. Results: Out of a total of 1239 patients, 125 patients had received dexmedetomidine and 1114 had received chloral hydrate. After 1:1 propensity score matching, the dexmedetomidine and chloral hydrate groups each had 118 patients. Testing completion rate with a single dose of medication was higher in the dexmedetomidine group (91.5% vs 71.2%; mean difference [95% CI] 20.3 [10.8‐29.9]; P <.0001; Pearson chi‐square value = 16.09). Sedation onset time was shorter in the dexmedetomidine group as well (16.6 ± 13.0 minutes vs 41.5 ± 26.8 minutes; mean difference [95% CI] 24.8 [19.1‐30.6]; P <.0001; T = 8.27). On the contrary, the duration of recovery was longer in the dexmedetomidine group (35.5 ± 40.2 minutes vs 18.5 ± 30.7 minutes; mean difference [95% CI] 18.6 [8.8‐28.5]; P =.0002; T = −2.82). Total residence time was not significantly different between the two groups (125.8 ± 40.6 minutes vs 122.1 ± 42.2 minutes, mean difference [95% CI] 5.21 [6.1‐16.5], P =.3665 T = 0.04). Conclusions: Intramuscular dexmedetomidine showed higher sedation success rate and shorter time to achieving the desired sedation level compared with oral chloral hydrate and thus may be an effective alternative for oral chloral hydrate in pediatric patients requiring sedation for electroencephalography. [ABSTRACT FROM AUTHOR]

The low coercivity in MnAl alloys has become a barrier to develop high performance MnAl‐based magnets for more than five decades. Herein, a high room‐temperature coercivity of 0.59 T in MnAl disc is achieved by severe plastic deformation. The grain size of the MnAl decreases significantly when ε‐phase is transformed into τ‐phase and when the τ‐phase is severely deformed. The aging process enhances the magnetization of the deformed τ‐phase significantly and reduces the coercivity of the MnAl disc to 0.396 T. The magnetic domain structure of the severely deformed τ‐MnAl exhibits many pinning sites in the intergranular regions and within the domains, resulting in the high coercivity of the bulk samples. The deformation process produces locally oriented texture of τ‐phase. This study opens a window for development of MnAl‐based bulk magnet with high coercivity and enhanced remanence. [ABSTRACT FROM AUTHOR]

Ultrafine particles and other hazardous materials are emitted during 3D printing, but the effect of temperature on such particles has not been studied systematically. The aim of this study was to evaluate the effect of temperature on the emission rate of particulate matter during fused deposition modeling (FDM) three‐dimensional (3D) printing using different filament types. The number concentration of particles was measured with direct‐reading instruments in an exposure chamber at various temperatures while using four filament materials during 3D printing. The temperature was increased from 185 to 290°C in 15°C increments, while incorporating the manufacturer‐recommended operating conditions. The emission rate increased gradually as the temperature increased for all filament types, and temperature was the key factor affecting the emission rate after filament type. For all filaments, at the lowest operating temperature, the emission rate was 107‐109 particles/min, whereas the emission rate at the highest temperature was about 1011 particles/min, that is, 100‐10 000 times higher than the emission rate at the lowest temperature. To reduce particle emissions from 3D printing, we recommend printing at the lowest temperature possible or using low‐emission materials. [ABSTRACT FROM AUTHOR]

High coercivity B-N-doped MnAl alloys were prepared by the traditional induction melting, high temperature homogenization, water-quenching, post-annealing, and severe plastic deformation process. The massive phase transformation of the ε→τ in the B-N-doped ε-MnAl occurs at the temperatures above 680 K and accomplishes at 760 K, both of which are slightly higher than those of the ε-MnAl without elemental doping. The Currie point of the B-N-doped τ-MnAl is measured to be 620 K, which is lower than that of the doping-free τ-MnAl. High-pressure torsion was employed to decrease the crystal size and increase the coercivity of samples. A coercivity up to 0.54 T was achieved in the B/N doped MnAl bulk sample after severe plastic deformation under 6 GPa. The aging processing on the severely deformed samples enhances the remanent magnetization significantly and decreases the coercivity slightly. Our work shows that the high-pressure torsion process is effective in developing coercivity in MnAl-based bulk magnet. [ABSTRACT FROM AUTHOR]

Nonmagnetic phase assisted low temperature phase MnBi bulk magnetic materials, i.e., MnBi/NaCl and MnBi/C magnets, were fabricated by hot pressing mixtures of MnBi and NaCl or C powders. The effects of nonmagnetic NaCl or C on the magnetic and physical properties of the MnBi bulks were investigated in detail. Identifications of phase stability and decomposition rate during the mixing and hot pressing processes were analyzed using the Rietveld refinement method. It was found that the coercivities (Hc) of the bulk magnets significantly increase with increasing content of NaCl or C: Hc of the MnBi bulks with NaCl of 5 wt. % and C of 5 wt. % reach 9041 Oe and 7054 Oe, respectively, which are higher than the pure MnBi bulk of 6272 Oe. This means that the addition of a small amount of NaCl and C in the MnBi bulks could be one of the promising routes to enhance their magnetic properties. [ABSTRACT FROM AUTHOR]

Ferroelectric Pb[sub 0.99][(Zr[sub 0.6]Sn[sub 0.4])[sub 0.85]Ti[sub 0.15]][sub 0.98]Nb[sub 0.02]O[sub 3] (PZSTN) thin films with different preferred orientations were fabricated by modifying with 20 mol% excess lead that contained a Pb(Zr[sub x]Ti[sub x-1])O[sub 3] seed layer (x = 0,0.3,0.52,0.65). Ferroelectric properties were investigated in terms of the texturing character of the PZSTN thin film. With an increase in Zr content in the seed layer, the (100) texturing of the PZSTN film was enhanced. The highly (100) texture (∼97%) was developed by inserting a seed layer with x = 1 between the Pt-coated substrate and the PZSTN thin film, whereas in the case of annealing in a reduced condition, the orientation of the film became nearly (111). The (111)-oriented PZSTN film showed relatively higher remanent polarization compared to that of the (100)-oriented film, while the (100)-oriented PZSTN film showed more fatigue behavior than the (111)-oriented film after 10[sup 9] switching cycles. The (111)-oriented PZSTN film with rhombohedral structure is believed to be suspected to significant stress along applied field direction, resulting in the production of many defects, causing degradation of the polarization during switching cycles. [ABSTRACT FROM AUTHOR]

To investigate the structural effect on the ferroelectric electron emission, the electric field distribution in a two-dimensional structure was calculated as a function of thickness and upper electrode diameter, and the switching charge density and emission charge were measured simultaneously. The simulation results of the electric field distribution showed that an asymmetric electrode structure caused a stray field on the bare surface of the ferroelectric cathode near the edge of upper electrode. The distance of the stray field from the electrode edge increased with increasing ferroelectric thickness, but it did not depend on the upper electrode diameter. The switching charge density increased more on the cathode with thicker ferroelectric and smaller upper electrode diameter. This was attributed to the difference of field distribution on the bare ferroelectric surface near the electrode edge. The expanded stray field for the thicker ferroelectric cathode enhanced polarization switching near the electrode edge. As a result, with increasing ferroelectric thickness, the emission charge increased and the threshold field decreased. However, there was no apparent difference between the emission charges from the different upper electrode diameters. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The dielectric and piezoelectric properties of sol-gel derived (x)Pb(Mg1/3Nb2/3)O3-(1 -x)Pb(Zr1/2Ti1/2)O3[(x)PMN-(1-x)PZT] thin films were investigated as a function of PMN content (x=0-1). For all compositions in the (x)PMN-(1-x)PZT thin films, a well-developed perovskite phase with (111) preferred orientation was obtained at the annealing temperature range of 700-800 degreesC. With increasing PMN content, the dielectric constant increased, while the remnant polarization and coercive field decreased. The enhanced dielectric properties were shown in the region of x= 0.2. At this composition, the dielectric constant and remnant polarization were 1750 and 12.75 C/cm2, respectively, which indicate that the morphotropic phase boundary (MPB) exists near the composition of x= 0.2. The transverse piezoelectric coefficient (d31) showed a maximum value of -84 pC/N at x = 0.2. These results confirmed that enhancement of the dielectric constant and remnant polarization improved the piezoelectric properties at the MPB. c 2001 American Institute of Physics. [DOI: 10.1063/1.1388572]
the main purpose of this investigation is to study the dielectric and piezoelectric properties of PMN-PZT thin films with various compositions and to develop a high-performance composition of the PMN-PZT thin film suitable for actuator applications. [ABSTRACT FROM AUTHOR]