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We demonstrated the feasibility of die-level process monitoring using spatially resolvable optical emission spectrometers (SROESs) in a low-pressure plasma reactor. The spatially resolved Ar emission line intensities and their intensity ratios were obtained from uniformly generated and intentionally perturbed plasma by inserting conductors of known sizes at known locations. The sheath and perturbed plasma distributions were identified from the Ar emission line intensity and their intensity ratio in the lateral direction to the SROES installment orientation. However, the resolution in the axial direction was insufficient to identify the sheath and perturbed the plasma distribution. We propose the superimposition of measured plasma emission intensities from two perpendicularly aligned SROESs for die-level process monitoring. The insufficient axial resolution can be compensated for by the lateral resolution of another SROES, and die-level process monitoring using SROES can thus be realized.

Evapotranspiration (ET) is the amount of water lost from the global surface, and it represents water and Earth's energy cycle. The intensity and frequency of climate variables have been changed because of the ongoing climate crisis, leading to increased climate disasters, such as heat waves and droughts. The abrupt climate crisis affects the variation of ET because climate variables highly influence ET. However, the future potential ET (PET) estimates include various uncertainty resulted from the variations in the projection of climate variables. In this context, the uncertainty in the projected future PETs should be quantified for the high reliability. Therefore, this study projected future global PET using Penman-Monteith (PM) for the near (2031-2065) and far (2066-2100) futures and quantified the corresponding uncertainty. The six climate variables of 14 CMIP6 GCMs were used for estimating historical PET which were compared to those from the NCEP/NCAR reanalysis data using the five evaluation metrics. The changes in PETs for four Shared Socio-economic Pathways (SSPs) scenarios were calculated for the near and far futures compared to the historical period (1980-2014). Subsequently, the uncertainties of PETs were quantified using the reliability ensemble average method. As a result, the future PET in high latitudes showed the most significant variability compared to the other latitudes. The future PET in the southern hemisphere was higher than the historical PET. Especially the PET in the mid-latitudes of southern hemisphere was the highest among the other latitudes. In addition, the uncertainty of PET was the highest in the high latitudes of the northern hemisphere while the mid-latitude in the northern was the lowest. This study provides insight into evaluating the global water cycle based on PET and helps establish appropriate policies for climate impact assessment.

Biodegradable materials have been received great attention as bone graft substitutes for bone regeneration and tissue engineering. However, their low mechanical property remains a major challenge for the use in load-bearing applications. Here, we developed mechanically reinforced composite scaffold containing adhesive levan as a binder for sintered hydroxyapatite (sHAp) and then examined the mechanical and thermal properties of the composite scaffold. We found that sHAp-levan composite scaffold exhibited remarkably enhanced mechanical strength, which is similar to that of polymethyl methacrylate (PMMA) bone cement. This composite scaffold can be utilized as a promising bone graft for bone regeneration and tissue engineering.

The design of efficient plasma reformers requires both efficient fuel conversion of fuel and chemical energy extraction. In this regard, liquid fuels provide the advantages of high gravimetric and volumetric energy densities, therefore yielding high energy; in particular, diesel is promising for use in plasma reformers. In this study, we investigated the ignition process in a diesel reformer driven by a rotating gliding arc using a high-speed camera. The locations of the flame kernel generated by the arc were clearly identified under different power conditions. At high power, the flame kernel was generated at the nozzle tip, which grew into a fully developed flame. This indicates that the period for fuel vaporization and mixing with air (which is a necessary step prior to chemical reactions and is typically longer than the characteristic chemical reaction time) is extremely short. Moreover, with low oxygen concentrations, we observed a rotating flame kernel. At low power, the flame kernel was generated at a distance from the nozzle tip and the arc. This result indicates that the generation mechanism of the flame kernel in the plasma reformer is not straightforward; flow and arc dynamics also influence the interactions between the arc and fuel droplets.

Controllability of the kinetic path of methane conversion in plasma driven oxidation reaction is investigated. Different geometries in a rotating gliding arc reactor are adopted to control reaction paths in methane oxidation reaction. Diverging and converging type reactor product different reaction environments in view point of both the reaction time and the degree of thermal activation. In the diverging reactor, the partial oxidation process is dominant with high methane conversion because the diverging section facilitates to elongate the arc length and decrease the flow velocity. Thus, the convective and radiative heat transfer from the arc column to the reactants could be enhanced. The role of plasma in the diverging reactor is mainly igniting and sustaining the partial oxidation, which is rather different from that in the converging reactor where the plasma plays as a heat source for thermal pyrolysis of methane with the help of focusing thermal energy of the arc.

The work presented in this report demonstrates that amphiphilic polysaccharide-clasped self-assembly (Amp-SA) with nanometer size, encapsulating hydrophobic nanoparticles (NPs) can be generated via electrohydrodynamic spraying. It is observed that the formation of hydrophobic NP-encapsulated Amp-SA is dependent on the surface chemistry of NPs. The citrate-coated magnetic NPs (MNPs-Cit) were also prepared and compared. The hydrophobic magnetic NP-encapsulated Amp-SA (Amp-SA-M) exhibited around 2.7-2.8-fold higher values in r2 relaxivity than that of MNPs-Cit. In addition, the resulting Amp-SA-M achieved ∼17.2-fold higher values in r2/r1 ratios than MNPs-Cit. The enhanced performances in magnetic transverse (r2) relaxivity and r2/r1 ratio as well as the in vivo behavior of Amp-SA-M suggest the potential of Amp-SA-M as a promising MRI nanoprobe. This approach based on the nature-originated amphiphilic biopolymers may provide a novel insight into electrohydrodynamic techniques that have the ability to create various nanostructures, encapsulating high-quality hydrophobic nanomaterials for applications in diverse biotechnology.

This study investigated the effects of a drink supplement containing Momordica charantia extract from bitter melon on physical fitness and levels of stress hormones during a four-week exercise training program in a hot environment. Ten male tennis players were orally administrated in a four-week (100 ml, 6 times a day), and the pre- and post-supplementation levels of different physical fitness variables and cortisol, and adrenocorticotropic hormone in plasma were measured at four time-points-before (baseline), during, and after the exercise, and on the next day of the supplementation. The findings showed that the supplementation has significant positive effects on enhancement of physical fitness parameters especially balance (d = 22.10, p = 0.013), flexibility (d = 4.83, p = 0.015), and cardiorespiratory fitness (d = 10.00, p = 0.030). Moreover, the adrenocorticotropic hormone levels were reduced during the exercise, and the cortisol levels showed the decreasing trend during and after the exercise, which was correlated with the change of cardiorespiratory fitness (r = 0.65, p

The double gamma quantile mapping (DGQM) can outperform single gamma quantile mapping (SGQM) for bias correction of global circulation models (GCMs) using two gamma functions for two segments based on 90th quantile. However, there are two ambiguous points: the 90th quantile and considering only the Gamma probability function. Therefore, this study introduced a flexible dividing point, δ (%), which can be adjusted to the regionally observed values at the station and considered the combination of various probability distributions, Weibull, lognormal, and Gamma, for two separate segments. The newly proposed method, flexible double distribution quantile mapping (F-DDQM), was employed to correct the bias of 8 GCMs of Coupled Model Intercomparison Project Phase 6 (CMIP6) to correct bias at 22 stations in South Korea. The results clearly showed higher performance of F-DDQM than DGQM and Flexible-DGQM (F-DGQM) by 25 % and 5 %, respectively, in root mean square error. The F-DGQM also showed better performance in replicating probability distribution, spatial variability and extremes of observed precipitation than other methods. This study contributes to improving the bias correction method for the better projection of extreme values.

This study compared the performance capabilities of three potential evapotranspiration (PET) methods, Thornthwaite (TW), Hargreaves and Samani (HS), and Penman-Monteith (PM), to simulate historical and future daily PET levels in South Korea using climate variables from Coupled Model Intercomparison Project 6 (CMIP6) Global Climate Models (GCMs). Five evaluation metrics were used to quantify the reproducibility of the climate variables and PETs at ten stations in South Korea for the historical period used here (1985-2014). The changes and uncertainty associated with the changes in PET in the near (2031-2060) and far (2071-2100) futures were calculated for two shared socioeconomic pathways (SSPs) of 2-4.5 and 5-8.5. As a result, PETs estimated using the three methods for the historical period showed high performance in terms of five evaluation metrics. Overall, PETs showed an increase for both the future periods and the SSPs. The PET estimated using the PM method showed the greatest increase, while that estimated using HS showed the most modest increase in the future. The PM method also showed the highest reliability and lowest uncertainty in the PET estimations, while the opposite was true for HS. This study contributes to our understanding of rational PET methods by which to calculate hydrological factors such as drought indexes for future periods via GCM simulations.

Plasma catalysis has been extensively investigated on both plasma and catalyst sides to explore the possible synergies, with most studies focusing on reactivity enhancement and the search for pathways other than those of simple plasma or catalytic reactions. However, there is currently much room for plasma applications beyond reactivity control in catalyst preparation and regeneration phases. This review introduces the use of plasma for accelerated catalyst regeneration and proposes a corresponding mechanistic explanation, showing that the effectiveness of this regeneration can be ascribed to the chemical and/or thermal effects of plasma such as the formation of reactive reductants/oxidants and cost-effective catalyst heat-up. Moreover, plasma-assisted catalyst regeneration is shown to involve low-temperature activation and gas-phase radical–based reactions, be a viable method of avoiding catalyst sintering during conventional high-temperature regeneration, and exhibit the advantage of cost effectiveness.

This study compared the performance of Long Short-Term Memory networks (LSTM) and Soil Water Assessment Tool (SWAT) in simulating observed runoff and projecting future runoff using 11 CMIP6 GCMs. The projected runoff was estimated for two Shared Socioeconomic Pathways (SSPs), 2-4.5 and 5-8.5 for near (2021-2060) and far (2061-2100) futures, respectively. The biases in GCM simulated climate variables were corrected using quantile mapping considering observations at 6 weather stations as reference data over the historical period (1985-2014). Five evaluation metrics were used to quantify the GCM's and hydrological models' capability to reconstruct climate variables and runoff in the Yeongsan Basin of South Korea. Uncertainties in LSTM and SWAT simulated runoff for the historical and projected periods were quantified using Bayesian Model Averaging (BMA) and reliability ensemble averaging (REA), respectively. The results showed significant improvement in bias-corrected GCMs in replicating observations in terms of all evaluation metrics. The extreme runoff estimated using general extreme value (GEV) distribution revealed the better capability of LSTM than SWAT in reproducing observed runoff at all gauging locations. The SWAT projected an increase (17.7%) while LSTM projected a decrease (-13.6%) in the future runoff for both SSPs at most locations. The uncertainty in LSTM simulated runoff was lower than in SWAT runoff at all stations for the historical period. However, the uncertainty in SWAT projected runoff was lower than LSTM projected runoff for both SSPs. This study helps assessing the ability of deep-learning versus physically-based models in hydrological modeling and therefore opens new perspectives for hydrological modeling applications.

An accurate microscopical analysis of blood smears requires a reproducible and convenient method of staining. Solution-based staining procedures can be cumbersome. Especially in low- and middle-income countries, the lack of skilled technicians and adequate laboratory facilities, as well as insufficient water and reagent quality, often become confounding factors. To overcome these obstacles, we developed a new cell staining method based on sequential stamping of agarose gel patches that contain eosin, methylene blue/oxidized methylene blue, Azure B, and buffer, respectively. Our method, termed "hydrogel staining", provides a simple, reproducible, solution-free, and inexpensive approach to stain blood cells. We have optimized incubation times to achieve the optimal transfer of dyes to fixed blood cells on a glass slide, with outcomes comparable to conventional solution-based methods for white blood cells and malaria-infected red blood cells. This hydrogel staining method does not require special skills to produce excellent quality stained blood film slides. The new method could enhance the accuracy of microscopical examination of blood smears, especially in resource-limited settings.

This study quantified the uncertainties in historical and future average monthly precipitation based on different bias correction methods, General Circulation Models (GCMs), Representative Concentration Pathways (RCPs), projection periods, and locations within the study area (i.e., the coastal and inland areas of South Korea). The GCMs were downscaled using deep learning, random forest, and nine quantile mapping bias correction methods for 22 gauge stations in South Korea. Data from the Korean Meteorology Administration (1970&ndash, 2005) were used as the reference data in this study. Two statistical measures, the standard deviation and interquartile range, were used to quantify the uncertainties. The probability distribution density was used to assess the similarity/variation in rainfall distributions. For the historical period, the uncertainty in the selection of bias correction methods was greater than that in the selection of GCMs, whereas the opposite pattern was observed for the projection period. The projection period had the lowest level of uncertainty in the selection of RCP scenarios, and for the future, the uncertainly related to the time period was slightly lower than that for the other sources but was much greater than that for the RCP selection. In addition, it was clear that the level of uncertainty of inland areas is much lower than that of coastal areas. The uncertainty in the selection of the GCMs was slightly greater than that in the selection of the bias correction method. Therefore, the uncertainty in the selection of coastal areas was intermediate between the selection of bias correction methods and GCMs. This paper contributes to an improved understanding of the uncertainties in climate change projections arising from various sources.

In leading edge patterning processes, overlay is now entangled with CD including OPC residuals and stochastics. This combined effect is a serious challenge for continued shrink and can be characterized with an Edge Placement Error (EPE) budget containing multi-domain components: global and local CD, local placement errors, overlay errors, etch biases and OPC. EPE defines process capability and ultimately relates to device yield. Understanding the EPE budget leads to efficient ways to monitor process capability and optimize it using EPE based process control applications. We examine a critical EPE use case on a leading edge DRAM node. We start by constructing and verifying the EPE Budget via densely sampled on-product in-device local, global CD and Overlay metrology after the etch process step. EPE budget contributors are ranked according to their impact to overall EPE performance and later with simulated EPE performance improvements per component. A cost/benefit analysis is shown to help choose the most HVM-friendly solutions.

The on-board reforming technique for de-NOx is attracting increasing interest because of the fast start-up and size of the device. However, due to the limited amount of energy available from the battery, a full understanding of the characteristics of the plasma reforming reaction is important to optimise this technology to achieve hydrogen production with minimal power consumption. This paper reports the relative role of the thermal effect of plasma in octane oxidation induced by rotating arc plasma. The thermal effect or gas temperature increased with increased electric power; the conversion of the electric energy to heat was estimated to be higher than 40%. The increased thermal effect was the main consequence of further increasing the plasma power, which controlled the syngas yield and was the main determinant of the energy efficiency of the reaction. In comparison, although the O-2/C ratio was the main parameter determining the thermal environment in the reactor, it had only a small influence on the energy efficiency of the reaction. The optimal O-2/C ratio for maximum energy efficiency depends on the electric power (e.g. the optimal O-2/C was 0.8 at 80 W and 0.5 at 280 W). The results provide guidance for determining the optimal conditions for plasma-driven reforming processes.

Arc plasma has been applied in diverse reactions because it can provide the mechanism for highly thermal activations. However, the efficiency of conversion from electrical energy to thermal energy for the reactant is not sufficiently high, resulting in challenges in practical applications of the arc in various chemical processes. In this study, a method is introduced to enhance the energy usage efficiency for the reactant. The enhancement is based on the control of the arc length elongation. An increase in the arc length results in an enhanced heat transfer from the arc column to the reactant, followed by the reduction of the conductive heat loss to the reactor body. The existing DC arc technologies cannot easily extend the arc length because of the arc instability. However, in this study, a novel AC arc technology was adopted that can support a stable arc with a sufficiently elongated length. Correspondingly, a comparative study on different arc lengths was conducted for the dry reforming (as a model reaction). The increased arc length results in an enhanced heat transfer to the gas or a higher gas temperature. This is followed by the enhancement of the conversions of the reactants for the same supplied electric power. The results provide a firm physical basis for further optimizations of the arc process for chemical reactions.

Social trust is defined as the belief that others in society can generally be trusted (Sztompka, 1999). The cross-country differences in social trust have been empirically demonstrated by a series of global surveys, and South Korea is ranked as one of the lowest groups. This study investigated whether/how this factor of social trust influences public acceptance of nuclear energy in South Korea. This study also proposed and tested a causal model explaining public acceptance of nuclear energy. Specifically, it was proposed that publics’ trust in diverse nuclear-related parties, and risk and benefit perceptions of nuclear energy directly influence the level of acceptance of nuclear energy. The postulated model was tested using structural equation modeling (SEM) procedures and data from the survey of 448 Seoul citizens between 20 and 59 years old. Results indicated that the proposed model fits the data well. It was found that social trust was not directly associated with acceptance of nuclear energy. Rather, it indirectly influenced public’s trust levels in different nuclear-related parties, which affect risk and benefit perceptions of nuclear energy, which in turn affect acceptance of nuclear energy. The practical implications of the results are discussed.

Due to their environmental friendliness, woodbased biomass pellets are widely used as conventional fuel sources in daily life and in various industries. Durability and proper mechanical strength are important quality factors for practical applications of biomass pellets as they enable their easy handling, transportation, and storage. In the present study, to increase mechanical strength of sawdust biomass pellet fuels, sucrose was employed as a main binder material. In addition, calcium ions were included as cross-linkers, which improved capability of modified binders. Even though sucrose alone enabled production of pellets with comparatively high compressive strength, addition of several calcium-containing substances further improved mechanical properties of sawdust pellets. Interestingly, we found that a combination of sucrose with CaCl2 (acidic blended solution) decreased, whereas addition of CaO or Ca(OH)2 (basic blended solution) considerably enhanced pellet strength. Thus, we concluded that calcium ions are able to form stable complexes with sucrose at basic pH levels (>10). Therefore, materials incorporating sucrose-calcium complexes can be successfully used as eco-friendly novel binders for the construction of durable biomass pellet fuels. Furthermore, their applications can be extended to formulations of nutritional or pharmaceutical substances.