Direct Mode Research Articles

Observation of higher-order gyrotropic modes and energy transfer in cylindrical ferromagnetic nanodots-based square lattices

We investigated and reported on a wide variety of gyrotropic modes in both isolated thick cylindrical magnetic vortices and lattices of such magnetic vortices arranged in square-lattice structures. In significantly thicker magnetic vortices, we see a higher-order flexure modes in addition to the uniform gyrotropic modes. We thoroughly examined the variation of the frequency and intensity of these modes with the thickness of the magnetic nanodots forming a vortex. We specifically looked at how the thickness, diameter, and aspect ratio of a single magnetic vortex and magnetic vortex lattice in various configurations affect the mode frequencies. When the magnetic vortex at the center is excited by an a.c. spin-polarized current with an excitation frequency equal to the collective gyrotropic frequencies of the lattice, we discuss the dynamics of the transfer of magnetic energy at three high symmetry points of the three-dimensional lattice of Permalloy nanodots with a vortex structure. The energy transmission in these lattice systems is estimated using the power and phase distributions for such configurations. Lattice configurations with substantially thicker nanodots consisting of uniform modes and higher-order flexure modes in the Eigen spectrum have transmission with uniform modes in specific directions and suppression in others, acting as a magnonic filter, and no transmission at all with higher-order modes. Such magnonic vortex lattice structures seek to improve the future prospects of technology and provide emerging applications in information processing devices, magnonic filters, three-dimensional waveguides, and magnonic crystals.

Characterizing linearity of a large area InGaAs photodiode in direct detection mode, at room temperature, from 100 pA to 10 𝛍A

Characterizing linearity of a large area InGaAs photodiode in direct detection mode, at room temperature, from 100 pA to 10 𝛍A

Vinylene-Linking of Polycyclic Aromatic Hydrocarbons to π-Extended Two-Dimensional Covalent Organic Framework Photocatalyst for H2O2 Synthesis.

Polycyclic aromatic hydrocarbons (PAHs) hold the predominant role either as individual molecules or building blocks in the field of organic semiconductors or nanocarbons. Connecting PAHs via sp2-carbon bridges to form high-crystalline p-extended structures is highly desired not only for enlarging the regimes of two-dimensional materials but also for achieving exceptional properties/functions. In this work, we developed 5,10-dimethyl-4,9-diazapyrene as a key monomer, whose two methyl groups at the positions adjacent to nitrogen atoms, can helpfully increase the solubility, and serve as the active connection sites. In the presence of organic acids, this monomer enables smoothly conducting Knoevenagel condensation to form two vinylene-linked PAH-cored COFs, which show high-crystalline honeycomb structures with large surface areas up to 1238 m2 g-1. Owing to the direct connection mode of PAH building blocks with vinylene, the as-prepared COFs possess spatially extended p-conjugation and substantial semiconducting properties. Consequently, their visible-light photocatalysis with exceptional activity and durability was manifested to generate H2O2 up to 3820 µmol g-1 h-1 in pure water, and even 17080 µmol g-1 h-1 using benzyl alcohol as a hole sacrificial agent.

Vinylene‐Linking of Polycyclic Aromatic Hydrocarbons to π‐Extended Two‐Dimensional Covalent Organic Framework Photocatalyst for H2O2 Synthesis

AbstractPolycyclic aromatic hydrocarbons (PAHs) hold the predominant role either as individual molecules or building blocks in the field of organic semiconductors or nanocarbons. Connecting PAHs via sp2‐carbon bridges to form high‐crystalline π‐extended structures is highly desired not only for enlarging the regimes of two‐dimensional materials but also for achieving exceptional properties/functions. In this work, we developed 5,10‐dimethyl‐4,9‐diazapyrene as a key monomer, whose two methyl groups at the positions adjacent to nitrogen atoms, can helpfully increase the solubility, and serve as the active connection sites. In the presence of organic acids, this monomer enables smoothly conducting Knoevenagel condensation to form two vinylene‐linked PAH‐cored COFs, which show high‐crystalline honeycomb structures with large surface areas up to 1238 m2 g−1. Owing to the direct connection mode of PAH building blocks with vinylene, the as‐prepared COFs possess spatially extended π‐conjugation and substantial semiconducting properties. Consequently, their visible‐light photocatalysis with exceptional activity and durability was manifested to generate H2O2 up to 3820 μmol g−1 h−1 in pure water, and even 17080 μmol g−1 h−1 using benzyl alcohol as a hole sacrificial agent.

Event-Driven Maximum Correntropy Filter Based on Cauchy Kernel for Spatial Orientation Using Gyros/Star Sensor Integration.

Gyros/star sensor integration provides a potential method to obtain high-accuracy spatial orientation for turntable structures. However, it is subjected to the problem of accuracy loss when the measurement noises become non-Gaussian due to the complex spatial environment. This paper presents an event-driven maximum correntropy filter based on Cauchy kernel to handle the above problem. In this method, a direct installation mode of gyros/star sensor integration is established and the associated mathematical model is derived to improve the turntable's control stability. Based on this, a Cauchy kernel-based maximum correntropy filter is developed to curb the influence of non-Gaussian measurement noise for enhancing the gyros/star sensor integration's robustness. Subsequently, an event-driven mechanism is constructed based on the filter's innovation information for further reducing the unnecessary computational cost to optimize the real-time performance. The effectiveness of the proposed method has been validated by simulations of the gyros/star sensor integration for spatial orientation. This shows that the proposed filtering methodology not only has strong robustness to deal with the influence of non-Gaussian measurement noise but can also achieve superior real-time spatial applications with a small computational cost, leading to enhanced performance for the turntable's spatial orientation using gyros/star sensor integration.

Initial results from neoclassical tearing mode stabilization experiment in KSTAR high normalized beta plasmas

Abstract Active stabilization of neoclassical tearing modes (NTMs) is critical for high beta plasma operation in the KSTAR tokamak. In recent device operation, an experiment was conducted to develop a m/n = 2/1 NTM stabilization in high normalized beta (β N) plasmas having β N > 3 by using electron cyclotron current drive (ECCD). The experiment is designed to first demonstrate the direct mode stabilization effect of the device EC system by varying the ECCD deposition location around the mode rational surface to prepare for future NTM stabilization in KSTAR using feedback schemes. In the experiment, the toroidal magnetic field strength, B T, is reduced to 1.5–1.6 T to create a highly localized ECCD profile on a large island width expected to produce a high stabilization effect. To align the ECCD with the mode, B T is varied between discharges by keeping the EC wave injection angles fixed to move the current deposition location across the q = 2 mode rational surface in ∼1 cm steps along the plasma midplane. The result shows a prompt reduction of the mode amplitude by ∼60% with a partial recovery of the loss of stored energy when the ECCD with 0.7 MW power is applied promptly after the mode onset at B T = 1.54 T. This abrupt reduction of the mode amplitude is significantly weaker or disappears in other discharges having slightly different B T in which the ECCD is deposited a few centimeters away. This result indicates a direct interaction between the driven EC current and the radially localized island structure first observed in the device. The EC ray-tracing analysis using the TORAY code shows that the applied EC-driven current aligns with the mode rational surface when the mode amplitude is observed to decrease. The stability of the observed 2/1 NTM is examined by constructing the modified Rutherford equation (MRE). The calculated EC power requirement for complete mode stabilization by assuming perfect alignment of ECCD on the mode is 0.8–1.7 MW by considering the uncertainties in the equation. This MRE-computed mode stability agrees with the experiment. The result projects that the present KSTAR EC system can stabilize the 2/1 NTM disrupting high β N plasmas, and provides the requirement of the mode-ECCD alignment for complete mode stabilization in future experiments in which an accurate alignment is planned to be made by feedback schemes being developed.

Association between blood heavy metals and diabetic kidney disease among type 2 diabetic patients: a cross-sectional study.

Studies on the correlation of exposure to metals with diabetic kidney disease (DKD) is scarce, especially concerning the impact of mixed metals on DKD. This study aimed to explore the association of blood heavy metals with DKD risk among type 2 diabetes mellitus (T2DM) patients. This cross-sectional study enrolled patients with T2DM in NHANES 2011-2020. ICP‒MS was applied to detect five metals, namely, Pb, Cd, Hg, Se and Mn, in blood. At the same time, the impacts of exposure to single and mixed metals on DKD were assessed using multivariable logistic regression, WQS, and BKMR models. The relationship was examined based on age, sex, BMI, hypertension, smoking status and PIR. Totally 2362 participants were enrolled for final analysis. Among them, 634 (26.84%) patients undergoing T2DM had DKD. Logistic regression indicated that, Pb (Q4: OR [95% CI]: 1.557 [1.175, 2.064]) was related to DKD when all covariates were adjusted. The WQS analysis, which was set in a positive directional mode, suggested that Pb was correlated positively with a higher incidence of DKD. In BKMR analysis, linear dose‒response curves were generated for Pb when fixing the other metals in the 50th percentile. In addition, exposure to mixed metals was significantly positively related to DKD. Subgroup analysis during logistic regression demonstrated that Pb was significantly and positively related to DKD in females, over 50 years, those with over 25kg/m2, no hypertension, no smoking status and under PIR. Serum albumin (ALB) did not regulate the indirect impact of blood Pb on DKD risk. The results showed that the increased mixed metal concentration may lead to an increased DKD risk among patients with T2DM. Blood Pb is positively related to the DKD risk in diabetic patients, especially, in females, over 50 years, those with over 25kg/m2, no hypertension, no smoking status and under PIR in T2DM patients. According to our observations, Pb absorption at least slightly influences DKD occurrence and progression. More studies are needed to validate the results in this work and illustrate the relevant biological mechanism.

A many-body quantum model is proposed as the mechanism responsible for accelerating rates of heat uptake by oceans as anthropogenic heat inputs rise

Abstract A recent many-body quantum approach to thermal radiation (Smith GB, et al 2022 J. Phys. Commun. 6, 065004) reveals that the energy capacitance of heated water is about twice its heat capacitance, due to energy stored as local hybrid pairs of photons coupled resonantly to local matter excitations, with pair density weighted by mass density. Energy exchange between photons and localised dipole excitations inside water at steady temperature T, occurs at sites where a hybridisation potential within the Hamiltonian couples local oscillation modes to ‘free’ photon modes. Photon modes in both directions are phase retarded at exit sides of a hybrid site. Optically sharp variations with frequency in the index of refraction n(f) and photon density of states follow. Exit spectral intensities at equilibrium temperature T carry quantum information on the energy density of matter excitations coupled to photons, while occupied hybrid sites are the source of all ‘free’ photons and internal spectral intensities. The matter excitations coupled locally to photons are distinct from those that define specific heat, but in water both arise from molecular oscillations. The energy capacitance CEX(T) of hybrid pairs depends on mass density and is independent of the heat capacitance CHT(T), which sets temperature T. CEX(T) is sensitive to T and doubles as a capacitance of energy and of ‘quantum information’. Expressions for CEX(T) are derived from first principles and applied to water. The density of occupied hybrids is amplified near surfaces by photons reflected off the surface, which create new hybrid pairs, but not extra heat. Energy capacitance CEX(T)+CHT(T) sets dT(t)/dt prior to a new equilibrium state emerging, after input heating rate dQ/dt is switched. Rising atmospheric intensities then raise T, dQ/dt, CEX(T) and CHT(T). The times available to cool overnight are fixed, so that a rising capacitance, adds to energy stored at an accelerating rate.

Generation of non-Gaussian states of light using deterministic photon subtraction

Abstract We explore a recently demonstrated deterministic photon subtraction scheme, based on single-photon Raman interaction with a Λ-type three-level atom, as a tool for manipulating quantum state of few-photon light pulses. We establish a comprehensive theoretical framework using input–output formalism and quantum regression theorem, enabling calculation of the first order autocorrelation matrices of the output light and identification of the temporal modes present in the generated light via their eigendecomposition. By modeling the entire system as a quantum network consisting multiple virtual cavities and a lambda-type emitter cascaded in two parallel guided modes of opposite propagation directions, we extract the quantum state occupying the modes of interest. For both squeezed vacuum and coherent light input pulses, the Wigner function of the output light after photon subtraction clearly reveals its non-Gaussian character. Furthermore, we propose a measurement-based scheme on the subtracted photon which can lead to conditional generation of quantum states resembling Schrodinger’s kitten state directly from coherent input light with fidelities above 99%. This result is particularly nothworthy, as coherent pulses, unlike the squeezed vacuum inputs commonly used in previous studies, are readily available in most experimental setups.

An Experimental Study on the Effect of GFRP and CFRP Strengthening on the Static and Dynamic Behavior of R/C Beams Under Progressive Damage

This paper aims to investigate the effect of glass fiber-reinforced polymer (GFRP) and carbon fiber-reinforced polymer (CFRP) strengthening materials on the static and dynamic behavior of reinforced concrete (R/C) beams subjected to progressive damage. Four identical beams, each strengthened with either GFRP or CFRP, are tested under a cyclic quasi-static loading pattern. Impact hammer tests are performed for undamaged states and various damage levels of the beams. The dynamic test data are analyzed using the Enhanced Frequency Domain Decomposition (EFDD) method to estimate the dynamic characteristics of the beams. In this context, the first three vibration modes in both vertical and horizontal directions are considered. Strengthening is applied to both pre-damaged and undamaged beams, enabling a comparison of their performance before and after the strengthening procedure. Beams strengthened with CFRP exhibit a higher load-bearing capacity and stiffness but also fail at lower displacement levels compared to those strengthened with GFRP, which demonstrate more ductile behavior. Furthermore, the modal frequency ratios indicate that the first vibration mode is more sensitive to damage than the second and third modes. This study highlights the effectiveness of both strengthening materials in enhancing the structural performance of both undamaged and damaged beams.

A pH-Responsive Ti-Based Local Drug Delivery System for Osteosarcoma Therapy.

Osteosarcoma is one of the major bone cancers, especially for youngsters. The current treatment usually requires systemic chemotherapy and the removal of bone tumors. Titanium (Ti)-based implants can be modified as local drug delivery (LDD) systems for controllable and localized chemotherapeutic drug release. In this work, a pH-responsive Ti-based LDD prototype was designed by introducing polydopamine (PDA) to release doxorubicin (DOX) around osteosarcoma cells with low pH. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and a contact angle meter were applied for surface characterization. Both direct and indirect cell culture modes were performed for biocompatibility and biofunction assessments. The results indicate that the Ti-based LDD prototype exhibits significant pH-dependent DOX release. The cumulative release can reach up to approximately 40% at pH = 6.0 after 72 h, but only around 20% at pH = 7.4. The Ti-based LDD implant shows good biocompatibility with approximately 93% viability of MC3T3 cells after direct culture in vitro for 24 h. Both direct and indirect culture modes verify the good anti-osteosarcoma function of the LDD implant, which should be attributed to the pH-responsive release of DOX.

Combustion characteristics of methanol engine applying TJI-HPDI with optimized pre-chamber nozzle structure under different injection and spark strategy

Methanol fuel faces challenges in achieving mixing controlled combustion (MCC) due to its low cetane number. This study proposes utilizing turbulent jet ignition to facilitate methanol MCC under high-pressure direct injection mode, namely TJI-HPDI. Three coordination schemes were developed numerically based on the projection angles between hot jets and main methanol spray plumes axis: opposing (Base design), opposing staggered (Design 1), and circumferential staggered interference (Design 2). Varied orifice diameters was employed to regulate jet energy and velocity. The results indicated that Design 2-BSB (Big-Small-Big orifice) scheme exhibited superior combustion and emission performance. Furthermore, the impact of start of main injection timing (SOI) on ignition and combustion characteristics was investigated under this scheme. An SOI of −12 °CA after top dead center (TDC), creating a 7 °CA interval between spark and SOI timing, achieved optimal ITE by minimizing the duration of CA10-CA50 and optimization methanol mixture distribution around hot jets. Additionally, pre-chamber (PC) spark ignition timing (ST) effects were also explored, with the optimal timing at −8 °CA ATDC. ST has minimal impact on heat release rate (HRR), because high-energy jets could ensure rapid and stable combustion. Moreover, the combustion stability of TJI-HPDI was demonstrated, underscoring the importance in understanding and optimizing TJI-HPDI ignition processes.

Evaluation on tension-compression anisotropic behavior of recycled asphalt mixture

The utilization of recycled asphalt pavement (RAP) is the effective way to improve resource conservation and reduce energy consumption. The asphalt mixture is a kind of typical anisotropic pavement materials due to its heterogeneity in composition and microstructure. This could lead to the differences of mechanical response between the tensile and compressive direction. However, there are limited researches to study the effect of RAP on the tension-compression anisotropic behavior of asphalt mixture. The strength, modulus and fatigue resistance tests are carried out and different loading modes are adopted. The results show that the tension-compression anisotropic behavior is more prominent with the increase of RAP content. The regenerant served as a kind of typical additive could alleviate this effect. In addition, the result of dynamic modulus test shows that the tension-compression anisotropic behavior has an increasing trend with the decrease of frequency and the increment of temperature. The ranking of fatigue life is opposite for the direct tensile and compressive loading mode, and the fatigue life ratio of compression to tension also show positive relation with the RAP content. Due to the difference in the stress mode, the fatigue life between the indirect tensile loading and four-point bending loading also show opposite trend, and the indirect tensile fatigue life has a larger discreteness.

Acoustic- Versus Intelligibility-Based Assessment of Subjective Listening Difficulty Measured With the Repeat-Recall Test.

To contrast interpretations of listening effort ratings when judged against acoustic- versus intelligibility-based normative references. Existing data collected from 66 normal-hearing adult listeners, comprising 2730 trials of the Repeat-Recall Test, were used to establish norms of subjective listening effort ratings for six ranges of intelligibility. Data from 21 aided hearing-impaired listeners were then used to contrast intelligibility-based norms against acoustic-based norms when interpreting listening effort ratings measured in omnidirectional and directional microphone conditions. Whereas acoustic-based norms effectively demonstrated reduced effort for directional versus omnidirectional microphone modes, intelligibility-based references controlled for listeners' performance biases and improved the consistency with which subjective ratings were ranked across the two microphone conditions. The choice of normative reference should be carefully considered when judging listening effort ratings from hearing-impaired individuals against those of their normal-hearing peers. Whereas acoustic-based references may be more useful for evaluating the benefits of hearing aid technology, intelligibility-based references may be better suited to identifying listeners with poor subjective experiences for speech-in-noise related to factors beyond intelligibility.

Qualitative and quantitative analysis of solid renal tumors by high-frame-rate contrast-enhanced ultrasound

ObjectiveTo analyze the characteristics of high-frame-rate contrast-enhanced ultrasound (H-CEUS) in solid renal tumors using qualitative and quantitative methods.MethodsSeventy-five patients who underwent preoperative conventional ultrasound (US), conventional contrast-enhanced ultrasound (C-CEUS), and H-CEUS examination of renal tumors were retrospectively analyzed, with a total of 89 renal masses. The masses were divided into the benign (30 masses) and malignant groups (59 masses) based on the results of enhanced computer tomography and pathology. The location, diameter, shape, border, calcification, and color doppler blood flow imaging (CDFI) of the lesions were observed by US, and the characteristics of the C-CEUS and H-CEUS images were qualitatively and quantitatively analyzed. The χ² test or Fisher’s exact probability method was used to compare the US image characteristics between the benign and malignant groups, and the image characteristics of C-CEUS and H-CEUS between the benign and malignant groups. Moreover, the nonparametric Mann-Whitney test was used to compare the differences in C-CEUS and H-CEUS time-intensity curve (TIC) parameters.ResultsSignificant differences in gender, surgical approach, echogenicity, and CDFI were observed between the malignant and benign groups (p = 0.003, < 0.001, < 0.001, = 0003). Qualitative analysis also revealed significant differences in the mode of wash-out and fill-in direction between C-CEUS and H-CEUS in the malignant group (p = 0.041, 0.002). In addition, the homogeneity of enhancement showed significant differences between the two contrast models in the benign group (p = 0.009). Quantitative analysis indicated that the TIC parameters peak intensity (PI), deceleration time (DT) /2, area under the curve (AUC), and mean transition time (MTT) were significantly lower in the H-CEUS model compared to the C-CEUS model in both the benign and malignant groups. (all p < 0.001). In contrast, ascending slope of rise curve (AS) was significantly higher in the H-CEUS model compared to the C-CEUS model in the malignant group (p = 0.048).ConclusionsIn renal tumors, H-CEUS shows clearer internal enhancement of the mass and the changes in the wash-out period. The quantitative TIC parameters PI, DT/2, AUC, and MTT were lower in H-CEUS compared to C-CEUS. Both the quantitative and qualitative analyses indicated that H-CEUS better displays the characteristics of solid renal masses compared with C-CEUS.

Documentary Practice as Praxis: A Direct Appeal to the Realization of the Social Act

The essential preoccupation of this paper is documentary practice as (social) praxis, the voice of the photography аs a direct mode of transmission and not only the discovery or mediation of reality. Alan Sekula's photographic discourse is taken as a case study, a practice that directly engages the subject – the position of the worker within the working class, critically representing the reality that is usually masked by spectacle. The hypotheses assume that the methodology of contextualization and discursivization of documentary photography (Untitled Slide Sequence, 1972) leads to a conscious perception of a historical and social reality. Using a cross-methodology of the author's theory and practice, referring to the author's critical point of view, Marxist and post-Marxist theories, this paper indicates that Sekula develops a specific photo-graphology concerned with the directness of expression, the literalness of meaning, and the unmasking of iconic signs captured by capitalist signifiers. The arguments underline that the use of documentary photography as a direct appeal can encourage the realization of a social act. The conclusion implies that the use of the author's voice in the direction of changing the movement of aesthetic production and reception leads to actualization, towards awakening of the passive component – confrontation with social stratification under capitalist order.

Highly efficient perovskite-based fuel electrodes for solid oxide electrochemical cells via in-situ nanoparticle exsolution and electron conduction enhancement

Developing efficient fuel catalysts exhibiting high electrocatalytic activity and stability is crucial to improving the performance of solid oxide fuel/electrolysis cells for electrochemical energy storage and conversion. The oxide catalysts have been extensively investigated for replacing conventional Ni-based fuel electrodes, owing to their excellent stability and high resistance to coking in the presence of carbon-based fuels, such as during CO2 electrolysis. In this study, we propose a novel strategy to enhance the oxide electrocatalyst performance via nanoparticle exsolution and electron conduction improvement. In this strategy, the A-site deficient Sr0.95Ti0.3(Fe0.9Ru0.1)0.7O3-δ (STFR) was coupled with Sr2Fe1.5Mo0.5O6-δ (SFM) to yield a composite electrode. STFR with in-situ exsolved Fe–Ru nanoparticles provided high catalytically active sites, whereas SFM increased the electron conduction pathways, further boosting the electrode activity. When the composited electrodes were applied to an LSGM electrolyte-supported cell, the Fe–Ru exsolved STFR–SFM exhibited superior activity, surpassing those of previously reported performance metrics, including >1.5 W cm−2 peak power density in fuel cell mode, >1.75 A cm−2 (at 1.3 V) in the steam electrolysis mode, and >2.15 A cm−2 (at 1.3 V) in direct CO2 electrolysis mode at 800 °C. The composite electrode demonstrates excellent electrochemical catalytic activity, remarkable durability, and preferential selectivity toward CO2 electrolysis.

Sensitivity and energy resolution of the Balqarad clover detector

Abstract This study investigates operational modes and veto techniques using the Balqarad clover system, focusing on energy resolution parameters like Full Width at Half Maximum (FWHM) and Full Width at Tenth Maximum (FWTM). Comparing with the GAMMA-X detector, clover consistently shows lower FWHM values (e.g., 1.08 keV vs. 1.45 keV for 133Ba), highlighting its higher precision. The clover system also achieves lower Minimum Detectable Activity (MDA) values (ranging from 1.19 to 1.56 Bq for 60Co and 137Cs in direct and addback modes), underscoring its enhanced performance compared to literature data. Practical MDA calculations using a reference soil sample reinforce the advantage of addback mode over direct mode in achieving more accurate measurements. These findings stress the critical importance of selecting the right measurement system for precise applications like radiation monitoring and nuclear safety assessments.

Air quality historical correlation model based on time series

Air quality is closely linked to human health and social development, making accurate air quality prediction highly significant. The Air Quality Index (AQI) is inherently a time series. However, most previous studies have overlooked its temporal features and have not thoroughly explored the relationship between pollutant emissions and air quality. To address this issue, this study establishes a historical correlation model for air quality based on a time series model—the Gaussian Hidden Markov Model (GHMM)—using industrial exhaust emissions and historical air quality data. Firstly, a traversal method is used to select the optimal number of hidden states for the GHMM. To optimize the traditional GHMM and reduce error accumulation in the prediction process, the Multi-day Weighted Matching method and the Fixed Training Set Length method are utilized. Both direct and indirect prediction modes are then used to predict the AQI in the Zhangdian District. Experimental results indicate that the improved GHMM with the indirect mode provides higher accuracy and more stable state estimation results (MAE = 13.59, RMSE = 17.59, mean forecasted value = 117.94). Finally, the air quality historical correlation model is integrated with the air quality meteorological correlation model from a previous study, further improving prediction accuracy (MAE = 11.59, RMSE = 14.87, mean forecasted value = 120.88). This study demonstrates that the GHMM’s strong ability to analyze temporal features significantly enhances the accuracy and stability of air quality predictions. The integration of the air quality historical correlation model with the air quality meteorological correlation model from a previous study leverages the strengths of each sub-model in handling different feature groups, leading to even more accurate predictions.

PRISM: three-dimensional sub-diffractive phase-resolved imaging spectroscopic method

We demonstrate a genuine method for three-dimensional pictorial reconstructions of two-dimensional, three-dimensional, and hybrid specimens based on confocal Raman data collected in a back-scattering geometry of a 532-nm setup. The protocol, or the titular PRISM (Phase-Resolved Imaging Spectroscopic Method), allows for sub-diffractive and material-resolved imaging of the object’s constituent material phases. The spacial component comes through either the signal distal attenuation ratio (direct mode) or subtle light-matter interactions, including interference enhancement and light absorption (indirect mode). The phase component is brought about by scrutinizing only selected Raman-active modes. We illustrate the PRISM approach in common real-life examples, including photolithographically structured amorphous Al2O3, reactive-ion-etched homoepitaxial SiC, and Chemical Vapor Deposition graphene transferred from copper foil onto a Si substrate and AlGaN microcolumns. The method is implementable in widespread Raman apparatus and offers a leap in the quality of materials imaging. The lateral resolution of PRISM is stage-limited by step motors to 100 nm. At the same time, the vertical accuracy is estimated at a nanometer scale due to the sensitivity of one of the applied phenomena (interference enhancement) to the physical property of the material (layer thickness).