Changes In Intensity Research Articles

Method to improve the classification accuracy by in situ laser cleaning of painted metal scraps during laser-induced breakdown spectroscopy based sorting

Abstract Scrap metals are typically covered with surface contaminants, such as paint, dust, and rust, which can significantly affect the emission spectrum during laser-induced breakdown spectroscopy (LIBS) based sorting. In this study, the effects of paint layers on metal surfaces during LIBS classification were investigated. LIBS spectra were collected from metal surfaces painted with black and white paints by ablation with a nanosecond pulsed laser (wavelength = 1064 nm, pulse width = 7 ns). For the black-painted samples, the LIBS spectra showed a broad background emission, emission lines unrelated to the target metals, large shot-to-shot variation, and a relatively low signal intensity of the target metal, causing poor classification accuracy even at high shot numbers. Cleaning the black paint layer by ablating over a wide area prior to LIBS analysis resulted in high classification accuracy with fewer shot numbers. A method to determine the number of cleaning shots necessary to obtain high classification accuracy and high throughput is proposed on the basis of the change in LIBS signal intensity during cleaning shots. For the white-painted samples, the paint peeled off the metal surface after the first shot, and strong LIBS signals were measured after the following shot, which were attributed to the nanoparticles generated by the ablation of the paint, allowing an accurate classification after only two shots. The results demonstrate that different approaches must be employed depending on the paint color to achieve high classification accuracy with fewer shot numbers.

Understanding the stress field at the lateral termination of a thrust fold using generic geomechanical models and clustering methods

Abstract. This study employs numerical simulations based on the limit analysis (LA) method to calculate the stress distribution in a model that includes a basal detachment, featuring the lateral termination of a generic fault under compression. We conduct 2500 2D and 500 3D simulations with varying basement and fault friction angles to analyze and classify the results into clusters representing similar failure patterns to understand the stress fields. Automatic fault detection methods are employed to identify the number and positions of fault lines in 2D and fault surfaces in 3D. Clustering approaches are utilized to group the models based on the detected failure patterns. For the 2D models, the analysis reveals three primary clusters and five transitional ones, qualitatively consistent with the critical Coulomb wedge theory and the influence of inherited structural and geometric aspects over rupture localization. In the 3D models, four different clusters portray the lateral prolongation of the inherited fault. High stress magnitudes are detected between the compressive boundary and the activated or created faults and at the root of the inherited active fault. Tension zones appear near the outcropping surface relief, while stress decreases with depth at the footwall of the created back thrusts. A statistical cluster-based stress field analysis indicates that for a given cluster, the stress field mainly conserves the same orientations, while the magnitude varies with changes in friction angles and compressive field intensity, except in failure zones where variations are sparse. Small parametric variations could lead to significantly different stress fields, while larger deviations might result in similar configurations. The comparison between 2D and 3D models shows the importance of lateral stresses and their influence on rupture patterns, distinguishing between 3D analysis and 2D cross-sections. Lastly, despite using small-scale models, stress field variations over a span of a couple of kilometers are quite large.

Multimodal HSI Combined with Multiblock Data Fusion: A New Tool for the Study of Time-Dependent Alteration Processes in Dyed Textiles.

The present study describes an innovative approach for the study of time-dependent alteration processes. It combines an advanced hyperspectral imaging (HSI) system, to collect visible reflectance and fluorescence spectral data sets sequentially, with a tailored multiblock data processing method. This enables the modeling of chemical degradation maps and the early, spatially resolved detection of dye alteration in textiles. A chemometric method based on data fusion and principal component analysis was employed to identify spectral features of dye degradation, combining and enhancing information from reflectance and fluorescence HSI data. The most significant spectral profiles extracted were used to develop an asymmetric Gaussian-based pixel-by-pixel fitting model applied to the HSI fluorescence data set, enabling the reconstruction of degradation maps for rapid and intuitive visualization. In particular, changes in intensities and horizontal shift of dye emission peaks were pixel-by-pixel evaluated and fitted for the reconstruction of the degradation maps. Artificially aged wool samples tinted with indigo carmine (IC) dye served as a case study. IC is extensively used in textiles, and it is notable for its light sensitive. The results show that this approach effectively identifies spatial variations and chemical changes in dyed wool fibers, offering potential for sustainable conservation of historical textiles and other types of time-dependent processes. Thus, by amplifying variation in spectral profiles induced over time by aging, even minimal changes at early stages can be easily detected and localized, offering powerful tools for future studies on food and drug shelf life and stability, as well as forensic trace analysis.

Development of a colorimetric/fluorescence dual-mode immunoassay for aflatoxin B1 based on streptavidin-induced gold nanoparticle aggregation.

Adual-mode immunoassay method was developed for colorimetric and fluorescence detection of aflatoxin B1 (AFB1) based on streptavidin-induced gold nanoparticle aggregation (AuNP@SA). AuNP-modified streptavidin-biotin labeling AFB1 complete antigen aggregations (AuNP@SA@Bio-BSA-AFB1) were synthesized as the competitive binding and dual-mode probe. AuNP@SA@Bio-BSA-AFB1 aggregations possessed high colorimetric and fluorescence quenching intensities. AFB1 antibodies modified immunomagnetic microspheres were used as the capture probe. The competitive binding between AFB1 and AuNP@SA@Bio-BSA-AFB1 leads to changes in color and fluorescence intensity. The detection limit of the colorimetric method is 6.95ng·mL-1, while that ofthe fluorescence method is 0.07ng·mL-1. The practicality of the proposed strategy was demonstrated bydetermining AFB1 in spiked peanut samples.

Head-mounted displays based on human eye condition variation patterns

In response to the practical demands for a wide field of view (FOV), long exit pupil distance, and high image quality in head-mounted displays, an initial structure was built based on the principles of catadioptric lenses in a folded optical path (pancake optics) and the field curvature correction formula. Subsequently, using even-order aspheric surfaces, a VR optical system was developed with a FOV of 2w=110∘, an exit pupil distance of 15 mm, and an exit pupil diameter of 8 mm. Compared to traditional designs, a human eye model was introduced as the image plane to construct a VR–human eye optical system analysis model, allowing for direct analysis of the retinal image quality under different states of the human eye. After that, based on medical statistical data, the impact of different light intensity conditions on the retinal image quality of the VR optical system was explored. Experimental results showed that changes in light intensity affect the pupil diameter, which, in turn, influences the final image quality of the system. To solve the issues, two solutions were proposed: adjusting the screen distance and changing the lens spacing. Both methods significantly improved the imaging quality on the human retina, with an increase of over 30% in the average MTF value. A comparison of these methods was conducted, providing valuable references for future VR optical system designs.

Examination of Sex-Related Differences in Fatigability and Frequency Components of Mechanomyographic Signals During Sustained Exercise

Background: Surface mechanomyographic (sMMG) signals have been used to examine sex-specific differences in the mechanical behavior of muscle during fatiguing exercise. However, studies often utilize simple amplitude- and frequency-based analyses, which only reveal the static components of the sMMG signal. Methods: Thus, a wavelet-based analysis was used to examine changes in the spectral intensity of the non-dominant limb’s vastus lateralis during a fatiguing, maximal, unilateral isometric leg extension in recreationally active men (n = 11) and women (n = 10). Relative changes in spectral intensities and instantaneous mean frequency (IMF) were examined using linear mixed-effect models. Time-to-task failure was compared using an independent sample t-test. Results: The neuromuscular responses demonstrated parallel decreases in IMF (p < 0.001). Further, there were parallel, nonlinear, decreases in spectral intensity across wavelets (p < 0.001) and there were no sex differences in time-to-task failure (p = 0.15). Conclusions: These data showed no sex-specific differences in exercise fatigability or muscle mechanics during fatiguing exercise of the leg extensors. However, when collapsed across sex, wavelet-specific changes in spectral intensity over time reveal novel insights into the interplay between low- and high-frequency components during fatigue.

The potential of Ti3C2Tx-KH2PO4 and Ti3C2Tx-chitosan in the efficient removal of cesium from nuclear wastewater

Ti3C2Tx is synthesized from Ti3AlC2 by two common methods, HF and HF in situ. The synthesis approach is very practical regarding the structure, morphology, space between layers, type and number of surface-active sites and its specific surface. XRD, SEM, EDS, FTIR and BET analyzes were used to investigate the structure, morphology, type and number of surface-active sites. Under the operating conditions of cesium initial concentration ~ 150 ppm, ambient temperature, pH ~ 7.00 and time of 60 min, the cesium adsorption intensity with Ti3C2Tx-HF and Ti3C2Tx-HF in situ was obtained as 194 and 219.5 mg.g− 1, respectively. The structural results of modification with KH2PO4 show that in this modification, in addition to the increase of hydroxyl functional groups, the distance between the layers has also increased and the cesium adsorption intensity has increased to 338.75 mg.g− 1 under the above operating conditions. Meanwhile, in modification with Chitosan by increasing the frequency of functional groups and specific surface up to 3 times the effective specific surface of Ti3C2Tx-HF in situ, no significant change in the cesium adsorption intensity has been observed (247.5 mg.g− 1). Experiments were conducted to evaluate the effect of parameters of initial concentration of Cs+ (250 − 50 ppm), time (30–60 min), ambient temperature (298.15–318.15 K), solution pH (3.0–11.0) with the help of RSM design. RSM results show that the pH parameter is one of the most important parameters affecting the cesium adsorption intensity with Ti3C2(OH)x and Ti3C2(OH)x-KH2PO4. Also, with the increase in temperature, the adsorption intensity should increase. It is shown in the isotherm modeling that R2 matches well with the Freundlich isotherm model, which is based on the layered structure of Ti3C2(OH)x and Ti3C2(OH)x-KH2PO4 and the presence of active sites with different energy levels, which leads to heterogeneous adsorption. The consistency will be of the adsorbent selectivity investigation shows that the Cs+ hydration radius plays a decisive role in its high adsorption potential. Reduction of MXene by 0.1 M HCl was carried out in 3 steps. The experimental results show that 15% absorption has been achieved in the third stage. The results of structural analysis show that its structure has not changed and the reduction of active sites as a result of washing with acid has led to a decrease in adsorption.

Femtosecond laser direct writing tilted fiber Bragg gratings in multicore fiber

In this Letter, we propose a new method utilizing femtosecond laser direct writing technology to rapidly inscribe high-quality tilted fiber Bragg gratings (TFBGs) in multicore fibers (MCFs). A series of TFBGs with varying tilt angles were directly inscribed in MCFs using the Plane-by-Plane (Pl-by-Pl) method, and the writing time for a 4 mm long TFBG was only 3.60 s. The TFBGs couple the transmitted light from the cores of the MCF into the cladding, thereby increasing the cross talk between adjacent cores. By monitoring the wavelength and intensity changes of the core modes coupled back to the central core from the TFBGs inscribed in the edge cores, two-dimensional (2D) vector bending measurements were achieved.

Efficacy of a TNF inhibitor in chronic low back pain with Modic changes type 1: The BackToBasic study A randomized controlled trial.

The efficacy of TNF inhibitors for treating chronic low back pain with Modic changes is uncertain. This study investigated the superiority of infliximab over placebo in patients with Modic changes type 1. In this multicenter, randomized, triple-blind, placebo-controlled trial, patients aged 18-65 with moderate to severe chronic low back pain and Modic changes type 1 were enrolled from five Norwegian public hospitals between January 2019 and October 2022. Participants were randomly assigned to four intravenous infusions of 5 mg/kg infliximab or placebo. The primary outcome was difference in change in the Oswestry Disability Index (ODI) score from baseline to 5 months. Secondary outcomes included changes in low back pain intensity, disability, and health-related quality of life. A linear mixed model was used for efficacy analyses. 128 patients (mean age 43 years, 65.6% women) participated (64 in each group). All patients who received at least one dose of the allocated infusion were included in the primary analyses. The average ODI score change was -7.0 (9.7) in the infliximab group and -6.4 (10.4) in the placebo group. The difference in the ODI change between the two groups was 1.3 ODI points (95% CI, -2.1 to 4.6; p= 0.45). Analyses showed no effect of infliximab compared to placebo on secondary outcomes. Adverse event rates were similar between groups. Infliximab did not demonstrate superiority over placebo in reducing pain-related disability in patients with moderate to severe chronic low back pain with Modic changes type 1 at 5 months.

Analysis of Flood Incidents in Manado City due to Rainfall Fluctuations (Case Study of the Tondano Watershed), Indonesia

Background Fluctuating rainfall intensity refers to the fluctuations or variations in the pattern of rainfall intensity over time in a certain area. This encompasses changes in intensity, duration, frequency, and spatial distribution of rainfall intensity occurring within a specific time frame. Objective This study investigates the fluctuation of rainfall and its relationship with flood occurrences in Manado City, particularly in the Tondano Watershed Area (DAS Tondano). Methods Average and maximum rainfall data are utilized to analyze recurring flood patterns. Results The analysis indicates that average rainfall intensity > 21.79 mm and cumulative rainfall > 52.64 mm, maximum rainfall intensity > 64 mm, and cumulative rainfall > 99.10 mm serve as threshold points for the onset of floods in Manado City. Conclusion Recommendations are made for continuous rainfall data collection in the Tondano Watershed area, especially Manado City, to support more effective flood control planning. The conclusions drawn from this analysis provide valuable insights into understanding and addressing flood risks in the region.

The role of diabatic heating/cooling in outer rainbands in the secondary eyewall formation and evolution in a numerically simulated tropical cyclone

In this study, the role of diabatic heating/cooling in outer rainbands (ORBs) in the formation and evolution of the secondary eyewall of a numerically simulated tropical cyclone (TC) is investigated. This is done through a series of sensitivity experiments under idealized conditions using a high-resolution cloud-resolving atmospheric model. The results show that artificially increasing diabatic heating in rainbands enhances convective activities in ORBs and leads to an earlier secondary eyewall formation (SEF), and later the faster weakening and earlier dissipation of the primary eyewall. Reducing diabatic heating in ORBs weakens the rainbands and delays the SEF but prolongs the duration of the double eyewall structure if the SEF occurs. Reducing diabatic cooling in ORBs enhances convective activity in rainbands but has little effect on convection in the primary eyewall prior to the SEF. However, it results in a widened eyewall structure and a stronger TC after the eyewall replacement. Increasing diabatic cooling in ORBs largely suppresses convection in rainbands and prohibits the SEF. These results demonstrate that diabatic heating/cooling in ORBs plays important roles in the SEF and evolution. Since diabatic heating/cooling in rainbands is sensitive to the near-core environmental relative humidity, our results demonstrate the critical importance of large-scale environmental moist condition to the formation and evolution of secondary eyewall in TCs. In addition, it is also found that when the area-averaged diabatic heating rate in ORBs becomes similar in magnitude to that in the primary eyewall, the secondary eyewall forms. Plain language summaryPrevious studies have demonstrated the importance of diabatic heating/cooling in outer rainbands to the structure and intensity changes of tropical cyclones (TCs) with a single eyewall. It is unclear whether and how diabatic heating/cooling in outer rainbands may affect the formation and evolution of the secondary eyewall in TCs. These issues have been addressed based on a series of sensitivity experiments under idealized conditions using a high-resolution atmospheric model. Results show that diabatic heating in outer rainbands is favorable for the secondary eyewall formation (SEF). Increasing diabatic heating in outer eyewall can lead to faster weakening and thus earlier dissipation of the primary eyewall. Diabatic cooling in outer rainbands suppresses convection in outer rainbands and prohibits the SEF. Since diabatic heating/cooling in outer rainbands is sensitive to the near-core environmental relative humidity, our results demonstrate the importance of the large-scale environmental moist condition to the SEF of TCs. We also found that when the area-averaged diabatic heating rate in outer rainbands becomes similar in magnitude to that in the primary eyewall, the secondary eyewall would form, which can be considered as a measure of the SEF in TCs. Key points1.Increasing diabatic heating in outer rainbands leads to earlier SEF, and faster weakening and earlier dissipation of the primary eyewall.2.Increasing diabatic cooling in outer rainbands suppresses convective activity in outer rainbands and is unfavorable for the SEF.3.When the area-averaged diabatic heating rate in outer rainbands and the eyewall become similar in magnitude, the secondary eyewall forms.

A novel chitosan/quercetin-based film enables non-enzymatic detection of glucose: Electrochemical and fluorescent behavior

In this study, a novel functional hydrogel film was synthesized using natural polymer chitosan and quercetin as raw materials. Fourier transform infrared (FT-IR) spectra and X-ray photoelectron spectroscopy (XPS) analysis indicate that phenylboronic acid modified carbon nanodots (PBA-CDs) were successfully prepared via a simple microwave-assisted hydrothermal method. The experimental results demonstrate that a dual electrochemical and fluorescence detection of glucose can be realized based on the boronate ester bonding between chitosan/quercetin (Chit0/Quer) films and PBA-CDs. The addition of PBA-CDs hinders the electron transfer between the phenolic hydroxyl groups of quercetin and the redox mediators, and inhibits the intramolecular rotation of quercetin, which leads to a decreased electrical signal and enhanced fluorescence intensity. After the addition of glucose, the peak redox current of the Chit0/Quer hydrogel film is restored due to the competitive binding of glucose to the boronate ester, resulting in a dual-input logic circuit for the qualitative detection of glucose. In addition, the fluorescence intensity of the hydrogel decreases with increasing glucose concentration, and the concentration of glucose can be quantitatively detected by detecting the change in fluorescence intensity. Besides, the sensor has better stability and selectivity for biomarkers. Finally, we demonstrate that the electrochemical and fluorescence sensing strategies can be used for the detection of glucose in real beverage samples. In conclusion, based on the redox activity of quercetin and the competitive binding of boronate ester bonds, we explored a new strategy for enzyme-free electrochemical and fluorescence sensing for the detection of glucose, which is expected to be applied in biomedicine, food industry and other fields.

Smart chitosan-based nanofibers for real-time monitoring and promotion of wound healing

Timely healing of acute wounds and stopping wound chronicity are current and future priorities in wound therapy. It is urgent and relevant to develop a wound dressing that has antimicrobial and monitors the wound microenvironment in real time. In this study, quaternary ammonium chitosan (HTCC) was selected as the antimicrobial agent and CS/PEO/HTCC nanofiber membranes (CPHs) were prepared by electrostatic spinning technique. The nanofiber membrane (CPH91) with the best antimicrobial performance was screened by the disk diffusion method and drug susceptibility testing by dilution method, and its antimicrobial effect on S. aureus was better than that of E. coli. Subsequently, functional carbon dots (CDs) were synthesized by solvothermal method and doped into CPH91 nanofibers by electrospinning. A good linear relationship between pH value (5.0–8.0) and the fluorescence intensity of CDs was observed. In addition, the nanofibers (CPH91@CDs) had good morphology, hydrophilicity, and biocompatibility. Changes in fluorescence intensity of CPH91@CDs at different pH (5.0–8.0) were monitored and converted into RGB values that were linearly fitted to pH value. Finally, the potential of CPH91@CDs of improving wound healing and instantaneously controlling wound healing process was confirmed by an infected wound model (S. aureus) on the back of SD rats.

An optical probe based on lanthanide light-emitting nanomaterials for detecting phosphate by ratiometric fluorescence method

Inorganic phosphate (Pi) not only sustains the physiological functions within organisms but also acts as an indicator of environmental water pollution. Thus, it is extremely significant to seek out a rapid and straightforward method for detecting Pi. In this paper, the lanthanide metal luminescent nanomaterial europium-pyromellitic acid (Eu-PMA, exhibiting characteristic fluorescence emission at 435 nm for PMA and 617 nm for Eu3+) is synthesized via a simple solvothermal approach and utilized as a probe for ratiometric fluorescence detection of Pi. As the amount of Pi increases, Pi has a strong complexation ability with ligand PMA, resulting in the structural damage of Eu-PMA. PMA cannot sensitize Eu3+ luminescence, thus the fluorescence intensity at 617 nm of the system is markedly decreased. Meanwhile, through energy transfer interaction, the fluorescence intensity at 435 nm of ligand PMA is weakly increased. Based on the ratio of the changes in fluorescence intensities of the two, a ratiometric fluorescence method is established for the detection of Pi. The method is not only rapid and simple, but also improves the sensitivity of Pi detection (Linear range is 0.1–90 mM). Moreover, the content of Pi in actual water samples has been analyzed and determined successfully by this method, which further broads the significance and application prospect of the ratiometric fluorescence method in detecting Pi.

A Northgrippian sedimentary magnetic enhancement along the western margin of India

Sedimentary magnetic records of shelf region contains complex environmental evolution information, necessitating records from various global regions to accurately interpret its significance. A sediment core (SSD-39/GC-01) retrieved from the eastern Arabian Sea was analyzed to elucidate the geologic and climatic controls on the sediment rock magnetic and grain size properties. We report the first record of high energy sediment deposits linked with intense monsoon phases, sea level variations, and extreme natural events during the Northgrippian period (8.27 ka to 4.20 ka). The compilation of magnetic susceptibility profiles of six sediment cores from the western margin of India revealed the presence of multiple sedimentary intervals of enhanced magnetic susceptibility and most likely reflect periods of high sedimentation events controlled by the regional geologic and climatic processes. We identified two anomalous sedimentary magnetic zones (Z-II, Z-IV) marked by an elevated magnetite content and sediment grain size, which reflect the periods of high-sedimentation events on the shelf off Goa. A shift in the magnetic mineral composition, clastic grain size, calcium carbonate, and organic carbon content at ~1.8 ka (Z-I) indicate a abrupt change in monsoon intensity. The elevated organic content within Z-I indicate efficient preservation of labile organic matter which survived oxidation due to rapid sediment deposition. End-member modeling of rock magnetic and grain size properties enabled us to discriminate and quantify the contributions of terrigenous fluxes and post-depositional mineral phases to the bulk magnetic mineral assemblage. We demonstrate that rapid scanning of magnetic susceptibility of sediment cores has the potential to precisely detect the periods of increased continental (magnetic flux) inputs into the marine shelf system. The proposed magnetic mineralogical approach has wider scope to constrain the understanding of how shelf sedimentation responded to past geological and climatic conditions globally.

Characterization of Wind Turbine Blade Deformation and Wake Flow Field with Different Numbers of Lay-Up Layers

The change in the composite lay-up method affects the blade stiffness, which in turn affects the structural dynamic and aerodynamic characteristics, but the influence law is not yet clear. In this paper, two-way fluid–structure coupling is used to study wind turbine blades with different numbers of lay-up layers. The analysis results show the following: (1) With the increase in the number of pavement layers, the maximum deformation of the blade tip decreases, the magnitude of the decrease also decreases gradually, and the growth trend of deformation along the blade spreading direction is gradually flattened. (2) The maximum stress–strain of the root of the blade gradually decreases, the tip of the blade is the opposite of the blade, the unevenness of the distribution of the stress–strain of the surface of the blade is gradually slowed down, and the concentration area is shifted back. (3) The different numbers of pavement layers affect the turbulence intensity of the blade in the flow field space. Herein, the spatial distribution trend of turbulence intensity in the flow field of wind turbine blades with different numbers of layers is basically the same, and the trend of turbulence intensity changes is gentle when the number of layers is increased. (4) The amount of the tip vortex in the wake stream of the wind turbine decreases, and the decay rate of the center vortex increases. A reasonable lay-up scheme can improve the deformation and stress of the blade, extend the service life of the blade, promote airflow mixing, and enhance the energy conversion efficiency.

Sensitive Fluorescent Determination of Matrix Metalloproteinase-2 (MMP-2) Using the Inner Filter Effect (IFE) with Carbon Dots and Aggregated Gold Nanoparticles

Matrix metalloproteinase-2 (MMP-2) is a key biomarker involved in various pathological processes, so its sensitive and selective detection is of great clinical significance. A fluorescent sensor for the detection of MMP-2 was successfully designed based on the inner filter effect (IFE) between carbon dots (CDs) and gold nanoparticles (AuNPs). In the presence of MMP-2, peptide chains are hydrolyzed, releasing short peptides that contain thiol groups and positive charges, thereby inducing the aggregation of AuNPs. This aggregation disrupts the IFE between AuNPs and CDs, leading to a significant enhancement of the fluorescence. By monitoring the change in fluorescence intensity of CDs, the concentration of MMP-2 was accurately determined. The sensor exhibited a linear response across the concentration range from 1.0 to 150 ng/mL, with a detection limit as low as 0.23 ng/mL, which is lower than those of previously reported methods. Furthermore, the sensor demonstrated minimal interference from coexisting biochemical substances for MMP-2 in human serum. Notably, the sensor was successfully applied to determine MMP-2 in human serum, showing satisfactory recovery rates ranging from 98.8 to 1106.0%. In conclusion, this fluorescent sensor offers high selectivity and sensitivity for MMP-2 detection, making it a promising tool for clinical diagnosis of related diseases.

A semi-automatic cardiovascular annotation and quantification toolbox utilizing prior knowledge-guided feature learning

Annotation and quantification of cardiovascular in intravascular ultrasound (IVUS) images are of great significance in assisting the clinical diagnosis and treatment of coronary heart disease. However, it is time-consuming and expensive for cardiologists to manually annotate cardiovascular and calculate parameters in IVUS images using different software during the diagnosis. In this paper, we propose an IVUS analysis toolbox (SaCAQ) for semi-automatic cardiovascular annotation and quantification via prior knowledge-guided feature learning. The SaCAQ consists of two main modules: (1) a semi-automatic cardiovascular annotation module and (2) a cardiovascular quantification module. The semi-automatic cardiovascular annotation module can accurately segment the vascular wall by a IVUS images segmentation model (ISM-IVUS). The ISM-IVUS first extracts vascular morphological features and pixel intensity change features for the complex image segmentation by the expert prior knowledge feature extraction mechanism. Secondly, vascular wall is accurately segmented by the multi-scale feature extraction of attention U-Net. Moreover, the segmentation result checking mechanism is applied to verify the automatic segmentation result, which enhances the reliability of SaCAQ. Plaque regions of interest to doctors are detected by the rule-based plaque detection method, which can assist in the quantification task. Finally, image measurement methods and medically recognized calculation formulas are used in the cardiovascular quantification module to obtain clinical parameters, which significantly improves the confidence of the results. The SaCAQ is verified on our own dataset containing 5242 IVUS slice images and 383 sets of parameters. The experiments demonstrate that the SaCAQ achieves high accuracy of vascular wall segmentation: mIoU of 86.16%, Dice coefficient of 93.43%, and Hausdorff distance of 0.2171 mm. Moreover, ISM-IVUS has good segmentation speed and robustness. The calculated parameters show good correlation and p-values. All of these results indicate that the proposed SaCAQ provides an efficient, accurate, and reliable toolbox for clinical diagnosis of cardiovascular disease. The SaCAQ and user manual can be publicly available from https://github.com/zHwiz/SaCAQ.

Multi-agent behavior strategies of WEEE recycling considering public participation under environmental regulation: A perspective of dual governance

To explore the dual management mechanism within the waste electrical and electronic equipment (WEEE) processing industry under environmental regulation, in this article we examine the role of public participation in supervision and incorporate degree variables into the strategic selections of national and local governments. Following this, we design a tripartite evolutionary game model, comprising the national government, local government, and recycler. We analyze the system stability strategies and conditions, and investigate the impact of pertinent factors on the behavior strategies of each subject. The findings reveal that adjusting the intensity of actions by both the national and local governments can significantly impact the time required for system stability, with changes in the regulatory intensity of the national government proving more effective. Active public participation emerges as a critical means to prompt proactive environmental measures by the local government and recycler. Intriguingly, increased public participation may drive the national government to opt for stricter regulatory strategies. Regarding the allocation ratio of special governance funds, an optimal value exists, and the local government can choose different ratios based on distinct objectives. In conclusion, to augment effective WEEE recycling management under environmental regulation, we make several recommendations. These include adjusting the allocation ratio of special governance funds and optimizing the penalty mechanism.

DrowsiScan: Early Detection of Driver Drowsiness using Deep Learning

In recent years, the rise in car accident fatalities has become a significant global concern, with road security emerging as a critical issue. Among the various factors contributing to road accidents, driver drowsiness stands out as a leading cause. This project aims to address this issue by developing a real-time driver drowsiness detection system using advanced machine vision techniques and deep learning models. Drowsy Driver Detection System has been developed using a non- intrusive machine vision based concepts. The system uses a small snap security camera that points directly towards the driver’s face and monitors the driver eyes in order to descry fatigue. In such a case when fatigue is detected, a warning signal is issued to warn the driver. This report describes how to detect the eyes, and also how to determine if the eyes are open state or close state. The algorithm developed is unique to any presently published papers, which was a primary ideal objective of the project. The system deals with using information attained for the double interpretation of the image to find the edges of the face, which narrows the area of where the eyes located. Once the face is detected, the eyes are found by computing the horizontal averages in the area. Taking into account the knowledge that eye regions in the face present great intensity changes, the eyes are located by chancing the significant intensity changes in the face. Once the eyes are located, measuring the distances between the intensity changes in the eye area determine whether the eyes are in open state or close state.A large distance corresponds to eye check. still, the system draws the conclusion that the driver is falling asleep and issues a warning signal, If the eyes are set up closed for 5 successive frames. The system is also suitable to detect when the eyes can not be set up, and works under reasonable lighting conditions.