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Stabilizing the interface between high-Ni oxide cathode and Li6PS5Cl for all-solid-state batteries via dual-compatible halides
No full textAll-solid-state batteries (ASSBs) with enhanced safety are promising next-generation energy storage systems for electric vehicles. However, the utilization of ASSBs is hindered by the high interfacial resistances between highNi-oxide cathodes and sulfide solid electrolytes (SEs). Passivating interphases form on the cathode in contact with the SE upon charging, deteriorating the power capability and cyclability. Inspired by the excellent stability of halides at high voltages, herein, we propose the interfacial engineering of LiNixCoyMnzO2 (NCM) and Li6PS5Cl (LPSCl) using Li+-conductive halides with 'dual compatibility'. The charge-transport and interfacial resistances of the halide-coated NCM (NCM@halide) electrodes are analyzed using a transmission-line-based impedance model. Impedance analyses indicate that the interfacial halide nanolayers slightly increase the Li+-transport resistance, but the NCM@halide electrodes exhibit considerably lower interfacial resistances than bare NCM. Furthermore, the interfacial resistance is highly dependent on the halide composition: NCM@Li2ZrCl6 2 ZrCl 6 shows a lower interfacial resistance than NCM@Li3InCl6 3 InCl 6 and NCM@Li3YCl6, 3 YCl 6 , resulting in superior rate-capability and cycling stability. The composition-dependent electrochemical properties of the NCM@halide electrodes are discussed in terms of the dual compatibility of the halides with NCM and LPSCl. This study offers an effective approach for addressing the interfacial challenges of sulfide-based ASSBs with high-Ni oxide cathodes.FALSEsciescopu
Rugged Island-Bridge Inorganic Electronics Mounted on Locally Strain-Isolated Substrates
No full textVarious strain isolation strategies that combine rigid and stretchable regions for stretchable electronics were recently proposed, but the vulnerability of inorganic materials to mechanical stress has emerged as a major impediment to their performance. We report a strain-isolation system that combines heteropolymers with different elastic moduli (i.e., hybrid stretchable polymers) and utilize it to construct a rugged island-bridge inorganic electronics system. Two types of prepolymers were simultaneously cross-linked to form an interpenetrating polymer network at the rigid-stretchable interface, resulting in a hybrid stretchable polymer that exhibited efficient strain isolation and mechanical stability. The system, including stretchable micro-LEDs and microheaters, demonstrated consistent operation under external strain, suggesting that the rugged island-bridge inorganic electronics mounted on a locally strain-isolated substrate offer a promising solution for replacing conventional stretchable electronics, enabling devices with a variety of form factors. © 2024 American Chemical Society.FALSEsciescopu
SYSTEM FOR B-SPLINE TEXTURE COEFFICIENT ESTIMATION AND METHOD FOR GENERATING HIGH-RESOLUTION IMAGES USING THE SAME
No full textQuadrotor Dynamics in a Wind Field: Equilibria Analysis and Energy Dissipation
No full textA widely used quadrotor model for designing controllers is based on rigid body dynamics, and it does not include the influence of wind, leading to several limitations. Namely, the quadrotor does not tilt when undergoing uniform linear motion; and it is not possible to account for energy dissipation due to wind and drag. To solve these two issues, we have added two types of aerodynamic drag due to wind into the quadrotor dynamics: propeller drag, and body drag. We conducted equilibria analyses of this model and observed that bifurcation occurs as the quadrotor body size is diminished. Through simulation, it was revealed that the model we propose overcomes the limitations of the rigid body model. Additionally, it has been demonstrated that the model we propose enables the calculation of energy dissipation due to wind, and the energy dissipation varies depending on the wind field distribution, even if the quadrotor’s trajectory is the same. This metric can serve as a cost function for a new path-finding problem, aiding in the more efficient operation of quadrotors. © ICROS, KIEE and Springer 2024.FALSEsciescopuskc
Parietal-Frontal Pathway Controls Relapse of Fear Memory in a Novel Context
Get PDFBackground: Fear responses significantly affect daily life and shape our approach to uncertainty. However, the potential resurgence of fear in unfamiliar situations poses a significant challenge to exposure-based therapies for maladaptive fear responses. Nonetheless, how novel contextual stimuli are associated with the relapse of extinguished fear remains unknown. Methods: Using a context-dependent fear renewal model, the functional circuits and underlying mechanisms of the posterior parietal cortex (PPC) and anterior cingulate cortex (ACC) were investigated using optogenetic, histological, in vivo, and ex vivo electrophysiological and pharmacological techniques. Results: We demonstrated that the PPC-to-ACC pathway governs fear relapse in a novel context. We observed enhanced populational calcium activity in the ACC neurons that received projections from the PPC and increased synaptic activity in the basolateral amygdala–projecting PPC-to-ACC neurons upon renewal in a novel context, where excitatory postsynaptic currents amplitudes increased but inhibitory postsynaptic current amplitudes decreased. In addition, we found that parvalbumin–expressing interneurons controlled novel context-dependent fear renewal, which was blocked by the chronic administration of fluoxetine. Conclusions: Our findings highlight the PPC-to-ACC pathway in mediating the relapse of extinguished fear in novel contexts, thereby contributing significant insights into the intricate neural mechanisms that govern fear renewal. © 2024 The AuthorsTRUEscopu
The genetically programmed rhythmic alteration of diurnal gene expression in the aged Arabidopsis leaves
Get PDFThe circadian clock regulates the daily pattern of temporal gene expression. In Arabidopsis, aging is associated with a shortening of the endogenous period of circadian rhythms under circadian conditions. However, the functional link between the circadian clock and aging under diurnal conditions and its physiological relevance remain elusive. In this study, we investigate and characterize the effect of aging on the waveforms of rhythmic gene expression patterns under light/dark cycles. Our analysis revealed that the diurnal rhythmic patterns of core clock genes undergo significant rhythmic alteration with phase shift and change of waveforms in aged plants compared to younger plants. Transcriptomic analysis indicated that this age-dependent rhythmic alteration occurs not only in core clock genes but also globally. Due to the rhythmic alteration patterns of the diurnal rhythmic gene expression, aged plants experience subjectively a shorter day and longer night. We also observed that genetic mutants of core clock component genes exhibited broadly yet distinctively altered changes in diurnal rhythmic gene expression patterns as aging progresses. Collectively, our findings support that age-dependent rhythmic alteration of diurnal gene expression rhythms reprograms the timetable of daily gene expression, leading to the physiological changes required for plant senescence. Copyright © 2024 Jung, Kim, Lee, Kang, Kim, Kim, Lim and Nam.TRUEsciescopu
Multi-UGV Task Reallocation for Sensor and Actuator Faults
No full textThis paper proposes a task reallocation method for multi Unmanned Grounded Vehicle (UGV) systems in sensor and actuator fault situations. The proposed method formulates the task reallocation problem as a Mixed-Integer Linear Programming (MILP) using the distance between UGVs and task priority. When a UGV sensor or actuator fault occurs, the proposed method solves the MILP and finds the optimal task reallocation solution. The solution ensures continuing high-priority tasks for the multi-UGV systems. The proposed method is validated in simulation and experiment. © 2024 ICROS
Drosophila HCN mediates gustatory homeostasis by preserving sensillar transepithelial potential in sweet environments
Get PDFEstablishing transepithelial ion disparities is crucial for sensory functions in animals. In insect sensory organs called sensilla, a transepithelial potential, known as the sensillum potential (SP), arises through active ion transport across accessory cells, sensitizing receptor neurons such as mechanoreceptors and chemoreceptors. Because multiple receptor neurons are often co-housed in a sensillum and share SP, niche-prevalent overstimulation of single sensory neurons can compromise neighboring receptors by depleting SP. However, how such potential depletion is prevented to maintain sensory homeostasis remains unknown. Here, we find that the Ih-encoded hyperpolarization-activated cyclic nucleotide-gated (HCN) channel bolsters the activity of bitter-sensing gustatory receptor neurons (bGRNs), albeit acting in sweet-sensing GRNs (sGRNs). For this task, HCN maintains SP despite prolonged sGRN stimulation induced by the diet mimicking their sweet feeding niche, such as overripe fruit. We present evidence that Ih-dependent demarcation of sGRN excitability is implemented to throttle SP consumption, which may have facilitated adaptation to a sweetness-dominated environment. Thus, HCN expressed in sGRNs serves as a key component of a simple yet versatile peripheral coding that regulates bitterness for optimal food intake in two contrasting ways: sweet-resilient preservation of bitter aversion and the previously reported sweet-dependent suppression of bitter taste. © 2024, Lee et al.TRUEsciescopu
Factors Influencing Sexual Experiences in Adolescents Using a Random Forest Model: Secondary Data Analysis of the 2019~2021 Korea Youth Risk Behavior Web-based Survey Data
Get PDFPurpose: The objective of this study was to develop a predictive model for the sexual experiences of adolescents using the random forest method and to identify the “variable importance.” Methods: The study utilized data from the 2019 to 2021 Korea Youth Risk Behavior Web-based Survey, which included 86,595 man and 80,504 woman participants. The number of independent variables stood at 44. SPSS was used to conduct Rao-Scott χ2 tests and complex sample t-tests. Modeling was performed using the random forest algorithm in Py-thon. Performance evaluation of each model included assessments of precision, recall, F1-score, receiver operating characteristics curve, and area under the curve calculations derived from the confusion matrix. Results: The prevalence of sexual experiences initially de-creased during the COVID-19 pandemic, but later increased. “Variable importance” for predicting sexual experiences, ranked in the top six, included week and weekday sedentary time and internet usage time, followed by ease of cigarette purchase, age at first alcohol con-sumption, smoking initiation, breakfast consumption, and difficulty purchasing alcohol. Conclusion: Education and support programs for promoting adolescent sexual health, based on the top-ranking important variables, should be integrated with health behavior intervention programs addressing internet usage, smoking, and alcohol consumption. We recommend active utilization of the random forest analysis method to develop high-performance predictive models for effective disease prevention, treatment, and nursing care. © 2024 Korean Society of Nursing Science.TRUEsciessciscopuskc
전자코용 3단자 인공 후각 센서 시스템의 성능 향상 연구
No full textArtificial olfactory sensorSensors for detecting odor molecules have been studied and reported employing various mechanisms such as chemical reaction sensors, resistive sensors, and field effect sensors. Conventional sensors are based on one-to- one matching with the target molecule, which can have limitations in selectivity and sensitivity. To overcome these problems and improve the sensor's performance, a multi-array thin-film transistor (TFT) with a polymer selector was studied. It was shown that the sensitivity and selectivity were significantly enhanced by the optimization of a device design, specific polymer selector thickness, and a measurement method. For the enhancement of the artificial olfactory system, the thickness of the polymer was varied to increase the sensitivity and the selectivity over which odor molecules can be detected. Since different types of polymers have various degrees of polarity, dielectric constant, molecular structure, and functional groups, these can be used to selectively detect odor molecules. In addition, the thickness of the polymer changes the electrical properties of the TFT by altering the overall capacitance value, the strength of the London force, the influence of polarization, and the absorption rate. As the polymer thickness varied, the response speed to odorant molecules varied. When detecting two types of odorants that have a similar chemical property or structure, the polymer thickness of the highest response speed was the same. The thickness at which the response speed was maximized was different from the thickness at which the reactivity was maximized. By comparing the radiation patterns of response and correlation coefficients of the TFT arrays, the optimal thickness of PAS was 210 nm, PS was 65 nm, SAA was 55 nm, and PVB was 35 nm. The sensor arrays were fabricated based on the optimized thickness of each polymer. Finally, the hardware budget and performance were optimized. The performance of the TFT sensors with polymer selectors was improved by controlling the TFT driving method. Drain current value and its response contrast of TFT were different corresponding to specific gate voltage when the sensor was exposed to odorant molecules. Among various gate bias conditions, a floating state of the gate showed the highest value of sensitivity and selectivity. Also, by applying a negative voltage to the gate in the recovery region, the recovery time was significantly reduced. This research could be applied to human-mimicking electronic noses, biosensors, and portable gas detectors.
Keywords: Polymer thickness, Floating state, Polymer artificial olfactory Sensor, IGZO TFT|냄새 분자를 감지하기 위한 센서로 화학반응 센서, 저항형 센서, 전계형 센서 등 다양한 메커니즘을 바탕으로 한 연구가 보고되고 있다. 종래의 센서는 감지 분자와 일대일 매칭이 기본이 되며, 선택성과 민감도에 한계가 있다. 이러한 문제를 극복하고 센서의 성능을 향상시키기 위해 고분자 셀렉터가 있는 다중 배열 박막 트랜지스터(TFT)를 연구하였다. 소자 설계, 고분자 셀렉터 두께 및 측정 방법의 최적화를 통해 감도와 선택성을 크게 향상시켰다.
인공 후각 시스템의 성능 향상을 위해, 고분자의 두께를 조절하여 냄새 분자를 감지할 수 있는 감도와 선택성을 높였다. 고분자 종류에 따라 극성의 정도, 유전율, 분자구조, 작용기가 다름을 이용하여 냄새 분자를 특이적으로 검출할 수 있다. 또한 고분자의 두께에 따라 전체 전기용량 값, 분산력의 세기, 분극의 영향, 흡수율이 달라져 TFT의 전기적 특성이 달라진다.
고분자의 두께가 달라짐에 따라, 냄새 분자에 대한 반응속도가 달라짐을 확인하였다. 화학적 특성이 비슷한 두 종류의 냄새 분자를 감지할 때, 반응 속도가 가장 빠른 고분자의 두께는 동일하였다. 반응 속도가 최대가 되는 두께는 반응성이 최대가 되는 두께와 달랐다. TFT 어레이의 응답 패턴과 상관 계수를 비교한 결과, 최적의 PAS 두께는 210nm, PS는 65nm, SAA는 55nm, PVB는 35nm로 나타났다. 각 고분자의 최적화된 두께를 바탕으로 센서 어레이를 제작하였다. 최종적으로, 하드웨어 예산과 성능을 최적화하였다.
고분자 셀렉터가 적용된 TFT 센서의 성능은 TFT 구동 방식을 제어하여 개선하였다. 센서가 냄새 분자에 노출되었을 때, 게이트 전압에 따라 TFT의 드레인 전류와 그 응답 비율이 달라졌다. 다양한 게이트 전압 조건 중, 플로팅 상태일 때 가장 높은 감도 및 선택성을 가졌다. 또한 회복 영역에서 게이트에 음의 전압을 인가하면 회복 시간이 크게 단축됨을 확인하였다. 본 연구는 인간의 후각기관을 모방한 전자 코나 바이오 센서 및 휴대용 가스검지기 등에 적용될 수 있을 것으로 기대된다.
키워드: 고분자 두께, 플로팅 상태, 고분자 인공 후각센서, IGZO 박막 트랜지스터Ⅰ. INTRODUCTION
1.1 Motivation 1
1.2 Multi array sensor 1
1.3 Sensor based on polymer film 2
1.3.1 Polymer film application 3
1.3.2 Effect of polymer film thickness on Sensor 4
1.3.3 Mechanism of interaction with odorants 6
1.4 Sensor based on transistor 9
1.4.1 Background of transistor 9
1.4.2 Application of transistor 9
Ⅱ. EXPERIMENTAL DETAILS
2.1 Device structure 11
2.2 Device material 13
2.3 Device fabrication 15
2.4 Measurement systems 17
Ⅲ. A STUDY OF THE CHANGES IN SENSING CHARACTERISTICS ACCORDING TO POLYMER THICKNESS
3.1 Changes in sensitivity according to polymer thickness 19
3.2 Changes in saturation speed according to polymer thickness 31
Ⅳ. A STUDY OF THE CHANGES IN SENSING CHARACTERISTICS ACCORDING TO MEASUREMENT METHOD
4.1 Changes in sensitivity according to voltage 35
4.1.1 Gate voltage control of the array sensor 35
4.1.2 Array sensor measured by floating state 37
4.2 Changes in recovery speed as reverse voltage 43
Ⅴ. RELAIBILITY OF MULTI-ARRAY SENSOR
5.1 Changes in array sensor characteristics according to storage environment 44
5.2 number of detections of array sensor 47
Ⅵ. CONCLUSIONMasterdCollectio