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Techno-Economic Analysis of Grid-Connected Highway Solar EV Charging Station
No full textSolar electric vehicle (EV) charging stations offer a promising solution to an environmental issue related to EVs by supplying eco-friendly electricity. Herein, we designed and analyzed a grid-connected highway solar EV charging station for 2022, 2030, and 2050 under two scenarios: Current policy scenario with restricted grid sales and policy mitigation scenario allowing grid sale. Future systems consider changes in EV charging station, grid CO2 emissions, carbon prices, and renewable costs. In 2022, high PV and battery costs led to a grid-only system. By 2030 and 2050, significant reductions in PV costs enabled systems with substantial PV capacity, especially under the policy mitigation scenario. Economic analysis showed that enabling grid sales reduces net present cost (NPC) by 40% in 2030 and 35% in 2050 compared to the current policy scenario, with significantly lower levelized cost of energy. CO2 emissions from EV operation are projected to be 44% and 3% of 2022 levels by 2030 and 2050, respectively. The policy mitigation scenario further reduces CO2 emissions by 22% in 2030 and 25% in 2050 compared to the current policy scenario. Sensitivity analyses reveal that increased grid sale capacity leads to higher renewable penetration and lower NPC but also increased grid congestion, highlighting the need for efficient grid management. Policymakers should consider revising regulations to support higher PV penetration and manage grid congestion. This study supports the transition to renewable systems and underscores the importance of policy measures in achieving sustainable energy goals.Y
In vitro recording and stimulation performance of multi-electrode arrays passivated with plasma-enhanced atomic layer-deposited metal oxides
No full textTo achieve an intimate contact between neuronal cells and the electrode in non-invasive platforms intended for neurological research, in this study, we fabricated a raised-type Au multi-electrode array (MEA) by employing nanoscale-thick indium-tin oxide (ITO; 50 nm) as a track layer and plasma-enhanced atomic layer-deposited (PEALD) Al2O3 (30-60 nm) and HfO2 (20 nm) as passivation layers. The PEALD Al2O3-passivated Au MEA was subsequently modified with electrodeposited AuPt nanoparticles (NPs) and IrOx to demonstrate the passivation capability and chemical resistance of Al2O3 to Au-, Pt-, and IrOx NP-containing electrolytes. Al2O3-passivated and IrOx/AuPt-modified MEAs could resolve optogenetically activated spikes and spontaneous activities with a root-mean-square noise level of 2.8 +/- 0.3 mu V generated by the primarily cultured hippocampal neurons transfected with viral vectors. PEALD Al2O3 exhibited a poor resistance to the Ag leaching environment (concentrated nitric acid maintained at 70 degrees C); therefore, a nanoporous Au (NPG) structure could not be implemented on the Au MEA passivated with Al2O3. By depositing a 20 nm-thick HfO2 over a 40 nm-thick Al2O3 layer, the NPG structure could be implemented on the Au MEA, confirming the chemical resistance of HfO2 to the Ag leaching environment. The nontoxicity of Al2O3 and HfO2 was confirmed by the successful primary culture of dissociated hippocampal neurons and electrophysiological studies performed using a hippocampal slice. Considering the advances in ALD technology and the vast number of metal oxides, these results extend the application of ALD metal oxides from water barriers for biomedical implants to passivation layers for in vitro MEAs.N
Languaging in Second-Language Acquisition: Review of Its Cognitive and Affective Roles in L2 Learning
No full textThis paper reviews languaging in SLA, with emphasis on its cognitive and affective roles in L2 learning. Based on Vygotskys Sociocultural Theory and Swains concept of languaging, this study examines the contribution of spoken and written languaging to L2 grammar acquisition, writing development, and learner motivation. Research suggests that languaging enhances metalinguistic awareness, thus helping learners analyze and refine their language use. Additionally, self-directed and collaborative languaging facilitate deeper cognitive engagement and self-regulation in learning. Studies pertaining to motivational languaging indicate that expressing language-learning goals in writing strengthens motivation and commitment to L2 learning. However, existing research focuses primarily on short-term effects, whereas the effects of individual differences, task design, and long-term engagement on the effectiveness of languaging are not sufficiently analyzed. This paper synthesizes the key findings, discusses the methodological limitations, and highlights the necessity for further investigating the effects of instructional scaffolding and learner characteristics on the sustained benefits of L2 languaging
Versatile Physics-based Character Control with Hybrid Latent Representation
No full textWe present a versatile latent representation that enables physically simulated character to efficiently utilize motion priors. To build a powerful motion embedding that is shared across multiple tasks, the physics controller should employ rich latent space that is easily explored and capable of generating high-quality motion. We propose integrating continuous and discrete latent representations to build a versatile motion prior that can be adapted to a wide range of challenging control tasks. Specifically, we build a discrete latent model to capture distinctive posterior distribution without collapse, and simultaneously augment the sampled vector with the continuous residuals to generate high-quality, smooth motion without jittering. We further incorporate Residual Vector Quantization, which not only maximizes the capacity of the discrete motion prior, but also efficiently abstracts the action space during the task learning phase. We demonstrate that our agent can produce diverse yet smooth motions simply by traversing the learned motion prior through unconditional motion generation. Furthermore, our model robustly satisfies sparse goal conditions with highly expressive natural motions, including head-mounted device tracking and motion in-betweening at irregular intervals, which could not be achieved with existing latent representations.Y
Impact of pelvic artery embolization on anti-Mullerian hormone levels in patients with postpartum hemorrhage: a prospective cohort study
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Enhancing Lithium-Mediated Nitrogen Reduction with Porous Polymer Fibers Featuring Lithium-Ion Affinity
No full textThe interaction between the electrolyte and working electrode surface affects the cascade of reactions involving Li deposition, N2, and proton carriers and consequently the NH3 production from Li-mediated nitrogen reduction reaction (Li-NRR). Efficient Li-NRR at low Li concentrations is particularly challenging because of low current density and uneven Li metal and lithium nitride plating. Here, the enhanced electrochemical production of NH3 for a low Li concentration of 0.5 m are demonstrated by employing 3D porous polymer fibers featuring Li+-affinity on Cu electrodes. Raman and IR spectroscopic analyses exhibit that the polymeric fibers composed of carboxyl and hydroxyl groups can form Li-binding complexes and decrease interactions with solvents and anions in the electrolyte. The electrochemical analyses support that this polymeric porous structure serves to retain Li+ near the electrode, expanding the active surface area and increasing current density. The Li-affinitive polymer fibers are effective even at a low Li salt concentration of 0.5 m to improve NH3 yield and Faradaic efficiency. This study underscores the importance of porous morphology, Li affinity, and its analytical methods in understanding Li-NRR.N
A customized guide device for single needle arthrocentesis on temporomandibular joint
No full textObjectives: This study aims to evaluate the accuracy and effectiveness of temporomandibular joint (TMJ) arthrocentesis using the three-dimensional (3D)-printed TMJ injection guide in cases of hemarthrosis caused by condyle fractures. Materials and Methods: A retrospective chart review was conducted for patients treated with the customized TMJ arthrocentesis guide to address hemarthrosis. Inclusion criteria included adults older than 18 years with condylar fractures not indicated for open reduction and internal fixation. The guide was fabricated using computed tomography or cone-beam computed tomography scans and 3D printing to control the degree and depth of the needle through the guide to aspirate hemarthrosis. Results: Six joints from five patients (average age 52.4 years) were treated using the guide. Post-procedural magnetic resonance imaging confirmed complete resolution of hemarthrosis in all cases. A representative case demonstrated successful outcomes with normal healing and no complications at 8 months post-procedure. Conclusion: The customized TMJ injection guide, using ear-based reference points, significantly enhances the accuracy and safety of TMJ arthrocentesis. This innovation is expected to increase the accessibility and effectiveness of TMJ-related treatments for clinicians without specialized TMJ expertise.N
Homeothermic P-Bit Computing Hardware with Stochastic Operations Beyond Limit of Non-Stochastic Materials
No full textProbabilistic computing (p-computing) is a customized approach for solving complex combinatorial optimization problems. However, issues of compatibility with well-established complementary metal-oxide-semiconductor (CMOS) technology, robustness to environmental temperature variations and stochasticity need to be addressed. This study resolves these difficulties using a metal-oxide-semiconductor field-effect transistor (MOSFET) with a floating body as a probabilistic-bit (p-bit) device. Unlike previously reported two-terminal p-bit structures, such as magnetic tunnel junction (MTJ) and memristor-based devices, a MOSFET is commercialized for conventional von Neumann computing. Although MOSFET operation is sensitive to the ambient temperature, a homeothermic characteristic from 20 degrees C up to 110 degrees C is achieved with gate voltage (VG) control, taking advantage of the three-terminal design. The conventional MOSFET operation is stable, reproducible, and, thus, non-stochastic. However, the floating body effect in this specific MOSFET enhances stochasticity, enabling an irregular single transistor latch (STL). Invertible logic operations and a max-cut solver are demonstrated with the proposed p-bits, maintaining desirable performance even at 110 degrees C through VG control. Due to its compatibility with CMOS technology, large-scale cointegration of a p-bit array and supportive CMOS circuits is feasible.N
Gate Engineering Effect in Ferroelectric Field-Effect Transistors with Al-Doped HfO2 Thin Film and Amorphous Indium-Gallium-Zinc-Oxide Channel
No full textThis work investigates the mechanism for the memory window (MW) suppression of the ferroelectric-thin film transistors (FETFTs) with an amorphous indium-gallium-zinc (a-IGZO) channel. a-IGZO generally has an n-type character with a high bandgap (>3 eV) and a high density of gap states, hindering the carrier type inversion. Therefore, the negative ferroelectric (FE) bound charges at the FE layer/a-IGZO interface must be compensated by the positive charges of the oxygen vacancy in the a-IGZO layer. In contrast, accumulated electrons can compensate for the positive FE-bound charges. Such a bound charge compensation mechanism complicates the FETFT operation and precise understanding. Experiments and simulations confirm that feasible FE switching in the bottom-TiN or P++-Si/Al-doped HfO2/a-IGZO/top-TiN structure can occur only when the countercharges in the a-IGZO layer compensate the positive and negative bound charges. More importantly, the Al-doped HfO2/a-IGZO interface generally involves electron trapping, which hinders FE switching and achieving a MW for the TiN gate case. When replacing the TiN gate with the P++-Si gate, the suppressed FE polarization by the depolarization effect from the SiO2 interface layer can mitigate electron accumulation. Consequently, the P++-Si bottom electrode (BE) is more advantageous than the TiN BE regarding a MW of FETFT.Y
Resistive Coupling of Bistable Resistor-Based Oscillators for Oscillatory Neural Network
No full textAn oscillatory neural network (ONN) is demonstrated by coupling a set of bistable resistor-based oscillators (birillators) through a coupling resistor (R-L). Each birillator is composed of a nonlinear bistable resistor (biristor) and a load resistor (R-C), which are connected in series. The synchronization behavior of oscillations among the resistively coupled birillators varies according to (R-C) . When an external sine-wave signal was applied to the resistively coupled birillators, the phase of the oscillations was binarized by second-harmonic injection locking (SHIL). These coupled birillators with SHIL solved combinatorial optimization problems.N