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PURPOSE The purpose of this study was to identify the scoring patterns of male and female Korean judo athletes by weight class, based on major international competitions from 2016 to 2021. METHODS We analyzed 1,508 scoring techniques, consisting of penalty, Waza-ari, and Ippon connected techniques, from male and female Korean athletes who participated in the Grand Prix, Grand Slam, Masters, World Championships, and Olympics. Chi-squared tests were conducted to examine differences in rounds, time, results, techniques, and continent by weight class.RESULTS In terms of differences in rounds, statistically significant differences were found in the men's lightweight and women's heavyweight categories. Statistically significant differences were found in the following: regarding differences in match time, in the men's heavyweight category; regarding match results, in the men's heavyweight category; and regarding differences in technique type, in the men's middleweight and heavyweight categories and in the women's lightweight and heavyweight categories. Finally, in terms of opponent continents, significant differences were found in both men's and women's lightweight categories. CONCLUSIONS In conclusion, this study confirmed the differences in wins and losses of male and female Korean athletes according to their weight classes. Based on this, it is necessary to analyze and systematize the technology types of the world's top athletes, including Korean athletes, to improve their judo performance.

Seoi-nage is a representative technique frequently used in judo. Therefore, it is essential to identify how seoi-nage force characteristics change under various conditions. This study aimed to determine the differences in the force characteristics at different performance heights of elite male judo athletes. Twenty elite male judo athletes participated in the study. They were asked to perform seoi-nage at different heights (80 cm and 60 cm) using a rubber band as a practice situation. Data were collected by a force-measurement device with a rubber band connected to the device. The time variables, force value magnitude, force value rate, and force value angle in the vertical/horizontal planes were calculated and compared at 80 cm and 60 cm. There were significant differences in the force magnitude and the force vector vertical angle at 80 cm and 60 cm (p

Reaction time is important to determine the performance of fencing. The purpose of this study was to investigate the reaction time and muscle activity and compare the movement among genders during Marche-fente. Fifteen Korean national Fleuret fencing athletes participated and were instructed to perform Marche-fente. Reaction time was measured with Plug & Play equipment and muscle activation was obtained by electromyography. The male athletes (0.94 ± 0.08 s) were faster than female athletes, who a performance of 1.03 ± 0.05 s. As the knee extensors activation was increased, the movement and response time was shorter (rectus femoris (RF); r = −0.526, p < 0.05, vastus lateralis oblique (VLO); r = −0.628, p < 0.05). In phase 1, men activated more knee extensors in the dominant leg, whereas the activation of knee flexors was increased to maintain a stable posture in women. Additionally, women used other muscles instead of large muscles such as RF and VLO in phase 2. In conclusion, female athletes activated knee flexors rather than knee extensors when moving the center of mass or generating a greater force. Less use of knee extensors is associated with knee injuries; therefore, exercise which activates knee extensors is required for females.

The conductive filament (CF) model, as an important means to realize synaptic functions, has received extensive attention and has been the subject of intense research. However, the random and uncontrollable growth of CFs seriously affects the performances of such devices. In this work, we prepared a neural synaptic device based on polyvinyl pyrrolidone-molybdenum disulfide quantum dot (MoS

The tapered channel effect is a major concern in three-dimensional (3-D) NAND technology because the effect causes differences in the electrical characteristics, including the threshold voltage (VT), between the upper and the lower cells. We simulated the tapered channel effect by using Sentaurus technology, computer-aided design (TCAD) tools, and based on the results, we propose a novel method to lessen the non-uniformity of the threshold voltage shift ( ${\Delta }\text{V}_{\mathrm{ T}}$ ) between the cells. The difference in ${\Delta }\text{V}_{\mathrm{ T}}$ between the upper and the lower cells due to the tapered channel can be reduced by employing a tapered blocking oxide layer with a proper taper angle. These results will be helpful in designing reliable 3-D NAND flash memories.

Tungsten disulfide (WS2) quantum dots (QDs) embedded in polyvinylpyrrolidone (PVP) based flexible memristive devices were prepared, and those devices exhibited typical bistable electrical switching and remarkable nonvolatile memristive behaviors. Maximum electricity ON/OFF ratio obtained from the current–voltage (I-V) curves of the device is close to 104. The set voltage of the device is +0.7 V, which effectively reduced the energy consumption. The retention times extracted from data for the devices were as large as 1 × 104 s, which points to these devices having nonvolatile characteristics. Moreover, the highly flexible characteristics of the devices were demonstrated by bending the devices. The carrier transport mechanisms were explained by fitting the I-V curves, and possible operating mechanisms of the devices can be described based on the electron trapping and detrapping processes. WS2 QDs uniformly dispersed in pure transparent N, N-Dimethylformamide (DMF) were obtained by using ultrasonication and a hydrothermal process in this work.

The motion blur of a large-size, organic, light-emitting device (OLED) panel could be reduced by decreasing the moving-picture response time (MPRT). The MPRT of an OLED display panel with a fast response was significantly affected by the frame frequency and the compensation driving method, and the MPRTs of large-size OLED display panels could be significantly decreased by using an integrated gate driver circuit with a MPRT reduction method. The MPRT was decreased due to the ability to turn the emitting pixels off in advance, which was possible due to the provision of black data. The integrated gate drivers were designed so that a normal display, black data insertion, and operation in the compensation mode could be achieved. The MPRT of a 65-inch ultra-high-definition (UHD) OLED panel was decreased to 3.4 ms by using an integrated gate driver circuit. The MPRT reduction method proposed in this study can reduce the MPRT time to below 6.8 ms according to the black data insertion duty. This MPRT time of 6.8 ms can be further reduced to 3.4 ms in 50% black data duty, showing a 50% MPRT improvement. Thus, the motion blur of such large-size OLED display panels can be significantly reduced by decreasing the value of the MPRT.

Purpose The purpose of this study is to overcome the shortcomings of 109C(Forward 4 ½ somersault) skill(Level 3.7) for two members of the men’s national diving team(YHR, KYN). Methods For qualitative analysis of the performed skill, three high-speed cameras and water-attached EMGs consisting of a total of ten placements were used. We instructed the two players to perform single-leg jump and double-leg jumps a total of three times each. Results The results of this study indicate that YHR and KYN appeared to increase their time or maintain the same time compared to the previous phase and displacement appeared higher when skill success occurred after the double-leg jump. The Shoulder & hip joints of YHR, KYN appeared larger in E2 and the hip joint of KYN appeared to increase in E1. Single-leg jump appeared similar or decreased the performed time of the previous phase in the last P5. YHR appeared larger only at a hip joint angle and KYN appeared smaller at the hip joint. The muscle activity(iEMG) of the two players appeared greater during skill failure than most of the muscles. Conclusions When perfectly performing 109C skills, the acquisition of medals in international competitions is possible. Therefore, in the future, it is necessary to study all of the variables that pertain to 109C.

This paper reports data for the electrical characteristics and the operating mechanisms of flexible resistive switching devices based on WS2 nanosheets (NSs) dispersed in a poly(methyl methacrylate) (PMMA) layer. The ON/OFF ratio of the memristive device based on an Al/WS2 NSs:PMMA/indium tin oxides (ITO) structure was approximately 5.9 × 104. The memristive device based on the WS2 NSs also exhibited the bipolar switching characteristics with low power consumption and great performance in the bent state with radii of the curvatures of 20 and 10 mm. Especially, the results obtained after bending the device were similar to those observed before bending. The device showed nearly the same ON/OFF ratio for a retention time of 1 × 104 sec, and the number of endurance cycles was greater than 1 × 102. The set voltage and the reset voltage probability distributions for the setting and the resetting processes indicated bipolar switching characteristics. The operating and the carrier transport mechanisms of the Al/WS2 NSs:PMMA/ITO device could be explained based on the current-voltage results with the aid of an energy band diagram.

Artificial synaptic devices based on natural organic materials are becoming the most desirable for extending their fields of applications to include wearable and implantable devices due to their biocompatibility, flexibility, lightweight, and scalability. Herein, we proposed a zein material, extracted from natural maize, as an active layer in an artificial synapse. The synaptic device exhibited notable digital-data storage and analog data processing capabilities. Remarkably, the zein-based synaptic device achieved recognition accuracy of up to 87% and exhibited clear digit-classification results on the learning and inference test. Moreover, the recognition accuracy of the zein-based artificial synapse was maintained within a difference of less than 2%, regardless of mechanically stressed conditions. We believe that this work will be an important asset toward the realization of wearable and implantable devices utilizing artificial synapses.

The central nervous system sends a neural impulse through an efferent nerve system toward muscles to drive movement. In an electronically artificial neural system, the electronic neural devices and interconnections prevent achieving highly connected and long-distance artificial impulse transmission and exhibit a narrow bandwidth. Here we design and demonstrate light-emitting memristors (LEMs) for the realization of an optoelectronic artificial efferent nerve, in which the LEM combines the functions of a light receiver, a light emitter, and an optoelectronic synapse in a single device. The optical signal from the pre-LEM (presynaptic membrane) acts as the input signal for the post-LEM (postsynaptic membrane), leading to one-to-many transmission, dynamic adjustable transmission, and light-trained synaptic plasticity, thus removing the physical limitation in artificially electronic neural systems. Furthermore, we construct an optoelectronic artificial efferent nerve with LEMs to control manipulators intelligently. These results promote the construction of an artificial optoelectronic nerve for further development of sensorimotor functionalities.

Fabrication of human-like intelligent tactile sensors is an intriguing challenge for developing human-machine interfaces. As inspired by somatosensory signal generation and neuroplasticity-based signal processing, intelligent neuromorphic tactile sensors with learning and memory based on the principle of a triboelectric nanogenerator are demonstrated. The tactile sensors can actively produce signals with various amplitudes on the basis of the history of pressure stimulations because of their capacity to mimic neuromorphic functions of synaptic potentiation and memory. The time over which these tactile sensors can retain the memorized information is alterable, enabling cascaded devices to have a multilevel forgetting process and to memorize a rich amount of information. Furthermore, smart fingers by using the tactile sensors are constructed to record a rich amount of information related to the fingers' current actions and previous actions. This intelligent active tactile sensor can be used as a functional element for artificial intelligence.

Simulating synaptic function and building brain-inspired computers have received widespread attention. The memristor is considered to be an electronic version of the synapse and an excellent element for creating a brand-new artificial intelligence system in the future. However, most memristor-based electronic synapses currently exhibit low stability due to complex resistance switching processes. Based on a controllable in-situ formation strategy that we were able to employ with atomic layer deposition, we fabricated electronic synapses based on Au@Al2O3 core-shell nanoparticles. Our device exhibited extremely reliable, stable, and durable performance and showed a capability to emulate biological synaptic behavior, including synaptic plasticity, long-term depression (LTD), long-term potentiation (LTP), amplitude dependence, and frequency dependence. This research provides a strategy for manufacturing highly-reliable electronic synapses for neuromorphic applications.

The effect of a modified cell structure in the gate region on the electrical characteristics of three-dimensional (3D) NAND flash memory devices was investigated by using a technology computeraided design simulation. The interference in the memory devices induced by the pass voltage (Vpass) interference of 3D NAND flash was significantly affected depending on the cell size. The Vpass memory device with a modified cell structure was reduced due to an increase in the electron density of the inversion layer in comparison with conventional 3D flash memory devices, and their program operation was enhanced by the increased electric field. Furthermore, the program/erase margin of the proposed 3D NAND flash memory device was 15% larger than that of the conventional 3D NAND flash memory device.

In this letter, we demonstrate the fabrication of flexible memristive devices using tungsten di-selenide (WSe2) quantum dots (QDs) as the active layer. The WSe2 QDs were synthesized by facile two-step technique consisting of solvothermal and sonication processes to utilize the charge-trapping sites in the memristive devices. The sizes of as-synthesized WSe2 QDs, as determined from the transmission electron microscopy image, were in the range between 3 and 5 nm. Current–voltage ( ${I}-{V}$ ) curves for the flexible memristive devices based on nanocomposites consisting of WSe2 QDs sandwiched between two poly (methyl methacrylate) (PMMA) layers showed remarkable bi-stable behavior before and after bending. The ON/OFF ratio of the memory devices before and after bending were approximately $1\times 10^{{2}}$ and $1\times 10^{{2}}$ , respectively. The devices showed the nonvolatile memory effect with a retention time of more than $7\times 10^{{2}}\text{s}$ . The endurance number of ON/OFF switching cycles for the devices was $1\times 10^{{2}}$ . The bipolar resistive switching behavior was described on the basis of the ${I}-{V}$ results by analyzing the effect of space charge.

Organic photovoltaic (OPV) cells based on Au@SiO2-WO3 nanocomposites (NCs) embedded into a hole transport layer (HTL) were fabricated to enhance the power conversion efficiency (PCE) of those cells. The morphology of the Au@SiO2-WO3 NC film was uniform without any aggregation of the Au nanoparticles (NPs) resulting from the existence in the SiO2 shell of the Au@SiO2 NPs. With the optimized Au@SiO2 NP concentration of 5 wt%, the short-circuit current density and PCE of the OPV cells were enhanced by 125% and 31%, respectively, compared to the OPV cells containing WO3 NPs. The PCE enhancement of the OPV cells with a Au@SiO2-WO3 NC HTL originated from an increase in the short-circuit current density due to the enhanced the photon absorption resulting from the localized surface plasmon resonance effect and the enhanced hole extraction capability of the Au@SiO2-WO3 NC HTL.

A novel deep-blue emissive dopant material, 2,7-bis(9,9-dimethylacridine-10(9H)-yl)-9,9-diphenyl-9H-thioxanthene 10-,10-dioxide (DMA-ThX), is synthesized for use in highly-efficient thermally activated delayed fluorescence organic light-emitting devices (TADF OLEDs). The molecular design of DMA-ThX retains the overlap between the lowest singlet excited state (S1) and the lowest triplet excited state (T1) because of its twisted molecular structure. From photoluminescence emission measurements at low temperature, the difference between the S1 and the T1 energy levels of DMA-ThX is found to be 0.07 eV. Furthermore, the external quantum efficiency of the deep-blue-emitting TADF OLEDs with DMA-ThX-doped bis[2-(diphenylphosphino)phenyl] ether oxide is 18.4%, which is significant, and the Commission Internationale de l'Eclairage coordinates are (0.14, 0.14), indicative of very pure deep-blue emission.

Healthy and uncomplicated lupus pregnancies exhibit early and sustained transcriptional modulation of lupus-related pathways. This might contribute to fetal tolerance while predisposing pregnant women to certain infections. Failure to modulate these pathways is associated with lupus pregnancy complications., Systemic lupus erythematosus carries an increased risk of pregnancy complications, including preeclampsia and fetal adverse outcomes. To identify the underlying molecular mechanisms, we longitudinally profiled the blood transcriptome of 92 lupus patients and 43 healthy women during pregnancy and postpartum and performed multicolor flow cytometry in a subset of them. We also profiled 25 healthy women undergoing assisted reproductive technology to monitor transcriptional changes around embryo implantation. Sustained down-regulation of multiple immune signatures, including interferon and plasma cells, was observed during healthy pregnancy. These changes appeared early after embryo implantation and were mirrored in uncomplicated lupus pregnancies. Patients with preeclampsia displayed early up-regulation of neutrophil signatures that correlated with expansion of immature neutrophils. Lupus pregnancies with fetal complications carried the highest interferon and plasma cell signatures as well as activated CD4+ T cell counts. Thus, blood immunomonitoring reveals that both healthy and uncomplicated lupus pregnancies exhibit early and sustained transcriptional modulation of lupus-related signatures, and a lack thereof associates with adverse outcomes., Graphical Abstract