Total Intensity Research Articles

Influence of tectonic stress field on oil and gas migration in the Tahe Oilfield carbonate reservoir: Identification of areas favorable for reservoir formation

An understanding of the tectonic stress field distribution in the carbonate reservoirs of the Tahe Oilfield is essential for oil and gas migration and reservoir reconstruction. This study adopts a geological genesis perspective and integrates the unique attributes of the carbonate reservoirs in the Tahe Oilfield to simulate three-dimensional stress fields using the finite element method and Petrel software. The simulation, which takes pore pressure and boundary constraints into consideration, aligns with the findings of acoustic emission tests conducted by previous researchers and validates the model by corroborating the maximum horizontal principal stress direction with imaging logging interpretations. With subsequent utilization of the generalized Coulomb-Mohr shear failure criterion and the Griffith generalized maximum tensile stress criterion, the simulated stress enables the prediction of the total fracture intensity. To complement this analysis, we integrate seismic data and fault formation mechanisms to characterize variations in fracture intensity within distinct regions of the study area. Three key findings emerge from this investigation. First, due to the Hercynian thermal event, X-shaped conjugate faults display a disproportionately high degree of development compared to other primary fractures. Analyzing the mechanisms of formation and development of these X-shaped strike-slip faults reveals discernible differences in deformation characteristics between NW-trending and NE-trending faults, with the former exhibiting a greater propensity for fracture rupture and efficient oil-gas migration. Second, fault intersections are critical and efficient conduits for fluid accumulation and thereby contribute to reservoir formation. Lastly, exclusive of X-shaped conjugate faults, NE-trending faults exhibit the greatest propensity for oil and gas accumulation and migration. Collectively, these findings facilitate the identification of areas favorable for oil and gas migration and provide a crucial mechanical analysis that can inform the exploration and development of the Tahe Oilfield.

Disinfection-residual bacteria (DRB) after chlorine dioxide treatment: Microbial community structure, regrowth potential, and secretion characteristics

This study investigates the effects of chlorine dioxide (ClO2) disinfection on the community structure, regrowth potential, and metabolic product secretion of disinfection-residual bacteria (DRB) in secondary effluent (SE), denitrification filter effluent (DFE), and ultrafiltration effluent (UE). Results show that ClO2 effectively reduces bacteria in SE and UE, achieving log removal values exceeding 3 at 1 mg/L within 30 min. A salient positive correlation (R2 > 0.95) exists between changes in total fluorescence intensity and disinfection efficacy. Post-treatment, Acinetobacter abundance increased in SE, while Pseudomonas decreased in DFE and UE. At lower ClO2 concentrations, Staphylococcus, Mycobacterium, Aeromonas, and Lactobacillus increased in DFE, but decreased at higher concentrations. After storage, bacterial counts in disinfected samples exceeded those in the control group, surpassing 105 CFU/mL. Despite an initial decline, species richness and evenness partially recovered but remained lower than control levels. Culturing DRB for 72 h showed elevated extracellular polymeric substances (EPS) secretion, quantified as total organic carbon (TOC), ranging from 5 to 27 mg/L, with significantly higher EPS in the disinfection group. Parallel factor analysis with self-organizing maps (PARAFAC-SOM) effectively differentiated water sample types and EPS fluorescent substances, underscoring the potential of three-dimensional fluorescence as an indirect measure of ClO2 disinfection efficacy.

Can place-based policy reduce carbon emissions? Evidence from industrial transformation and upgrading exemplary zone in China

The effect of the place-based policies on sustainable development has received substantial attention in economic research. In China, the industrial transformation and upgrading exemplary zone policy is a prominent example of such policies, as it targets old industrial and resource-based cities. The paper provides an early assessment of the policy’s capability to reduce carbon emissions. Specifically, we use data from old industrial and resource-based cities for the period of 2012–2019 and apply the difference-in-differences method to examine the policy’s influence on total carbon emissions and intensity. The results show that the policy can effectively reduce carbon emissions through reducing energy consumption, promoting urban green innovation and tertiary industry agglomeration. Compared to resource-based cities, cities with a low level of economic development and central, western cities, this impact is more notable in old industrial cities, cities with a high level of economic development and eastern cities. Additional analysis reveals that the policy has beneficial spatial radiation impacts on the nearby cities as well. In the meanwhile, the strategy may have a synergy effect on reducing carbon emissions and pollution. The results of this study may have an impact on how nations implement place-based policies and reduce carbon emissions.

Patterns of 12-Month Post-Myocardial Infarction Medication Use According to Revascularisation Strategy: Analysis of 15,339 Admissions in Victoria, Australia

Clinical guidelines recommend secondary prevention medications following myocardial infarction (MI) regardless of revascularisation strategy. Studies suggest that there is variation in post-MI medication use following percutaneous coronary intervention (PCI) and coronary artery bypass grafts (CABG). We investigated initial dispensing and 12-month patterns of medication use according to revascularisation strategy following non-ST-elevation MI (NSTEMI). We included all public and private hospital admissions for NSTEMI for patients aged ≥30 years in Victoria, Australia, between July 2012 and June 2017. We investigated initial dispensing of P2Y12 inhibitors (P2Y12i), statins (total and high intensity), angiotensin-converting-enzyme inhibitors (ACEi)/angiotensin receptor blockers (ARB), and beta blockers within 60 days after discharge. Twelve-month post-MI medication use was estimated as the proportion of days covered (PDC) over a 12-month period from the date of hospital discharge. Analyses were performed using adjusted regression models, stratified by revascularisation strategy. There were 15,399 admissions for NSTEMI: 11,754 with PCI and 3,645 with CABG. Following adjustments, predicted probability of initial dispensing in the PCI and CABG groups, respectively, was 0.94 (95% confidence interval 0.93-0.95) vs 0.17 (0.13-0.21) for P2Y12i; 0.69 (0.66-0.71) vs 0.42 (0.37-0.48) for ACEi/ARB; 0.59 (0.57-0.62) vs 0.69 (0.64-0.74) for beta blockers; 0.89 (0.87-0.91) vs 0.89 (0.85-0.92) for statins; and 0.60 (0.57-0.62) vs 0.69 (0.63-0.73) for high intensity statins. The 12-month PDC in the PCI and CABG groups, respectively, was 0.82 (0.80-0.83) vs 0.12 (0.09-0.15) for P2Y12i; 0.62 (0.60-0.65) vs 0.43 (0.39-0.48) for ACEi/ARB; 0.53 (0.51-0.55) vs 0.632 (0.58-0.66) for beta blockers; 0.79 (0.78-0.81) vs 0.78 (0.74-0.81) for statins; and 0.49 (0.47-0.51) vs 0.55 (0.50-0.59) for high intensity statins. Post-discharge dispensing of secondary prevention medications differed with respect to revascularisation strategy from 2012 to 2017, despite clear evidence of benefit during this period. Interventions may be needed to address possible clinician and patient uncertainty about the benefits of secondary prevention medications, regardless of revascularisation strategy.

Analysing short-term training load distribution in elite European basketball: an exploration under six head coaches

ABSTRACT The study aimed to analyse and comprehend the variability in training load periodisation among elite basketball coaches, identifying specific strategies employed during different stages preceding matches. The external workload was monitored during the three practices prior to the first match of the week using wearable microtechnology over six seasons (2016–17 to 2021–22). Eight variables were collected for analysis during all sessions and across the six coaches: total duration, Player Load (PL), accelerations (ACC), decelerations (DEC) and number of JUMPS in both total (t) and high intensity bands (h). The study revealed significant variations in training load variables across pre-match sessions, with MD-1 showing distinct differences compared to MD-3 and MD-2. Coaches exhibited diverse approaches in managing external load variables, particularly evident in MD-3 where Co1 imposed the lowest load and Co3 the highest. Results showed significant variability in training load variables across pre-match sessions, with MD-1 exhibiting distinct differences compared to MD-3 and MD-2. Significant variability was observed among coaches for each MD. While there was a general trend that all coaches followed to some extent, each coach still had their unique methods or strategies, and these differences were most apparent during the MD-3.

Vine spacing of <i>Vitis vinifera</i> cv. Shiraz/101-14 Mgt. III. Grape and wine quality

Vine spacing effects of Shiraz/101-14 Mgt on a relatively high potential soil in the Breede River Valley, Robertson, South Africa, on grape composition and wine quality, were investigated. Canopies were VSP trellised and orientated approximately NNE-SSW. Spacing between rows was fixed at 2.2 m. In-row vine spacing changed from 0.3 – 4.5 m with increments of 30 cm (from 15151 – 1010 vines/ha). Grape composition and wine quality were monitored over six seasons and two grape ripeness levels. Decreasing trends of soluble solids (°B) and pH and increasing titratable acidity from narrow to wide spacing were observed. Sugar accumulation of wider spacings seemed delayed. Berry skin total anthocyanin index and phenol content showed virtually no change. Malvidin mono-glucoside and its p-coumaroyl and acetyl derivatives were present in the highest concentrations, followed by peonidin-, petunidin-, delphinidin- and cyanidin mono-glucosides and derivatives, each vine spacing treatment displaying a unique grape anthocyanin profile. The narrower spacing of vines seemed to favour skin anthocyanin accumulation compared to wider spacing. Decreasing trends in wine total anthocyanin intensity, anthocyanin density, and phenols were observed from narrow to wide spacing; all had higher levels in wines from riper grapes. Individual wine anthocyanin concentrations also showed qualitative profile changes. The first regression join points for all anthocyanins occurred around 1.8 – 2.4 m vine spacing; those for malvidin and derivatives consistently appeared at 1.8 m spacing. Although volatile compounds only seemed to respond to ripeness level and not to vine spacing, wine sensory quality generally decreased with wider vine spacing at both grape ripeness levels. Given the changes in biotic and abiotic growth conditions with wider vine spacing, the results likely displayed adaptation to the combined impact of increasing light exposure, berry temperature, physiological functioning, vegetative and reproductive growth ratios, and plant stress. The study showed the prominent role of plant spacing in sustainable grape growing and wine outcomes and thus the importance of judicious decision-making during the establishment and management of vines under any growth conditions and in any terroir.

Revealing the Hidden Paleomagnetic Information from the Airborne Total Magnetic Intensity (TMI) Data

Revealing the Hidden Paleomagnetic Information from the Airborne Total Magnetic Intensity (TMI) Data

Analysis of the carbon emissions trend in the Indian manufacturing sector: a decomposition and decoupling approach.

There is a growing emphasis on fostering green growth and lowering carbon emissions in order to achieve sustainable economic development. This study uses the Tapio decoupling model and analyzes the factors influencing changes in carbon emissions from manufacturing in India utilizing the log mean Divisia index (LMDI) techniques. Furthermore, the nexus between carbon emission intensity, information and communication technology (ICT), total factor productivity (TFP), skill, and energy intensity has been analyzed using the system-GMM approach. It is based on the plant-level Annual Survey of Industries (ASI) datasets for the organized manufacturing sector of India from 2001 to 2002 to 2019 2020 for the major 21 Indian states/UT. The findings reflect the presence of weak decoupling in the manufacturing sector both at the aggregate level and in states. This indicates that both output and emissions are increasing; however, output growth surpasses emission growth, which signifies an effort to transition towards more environmentally friendly production methods and enhanced energy efficiency. The output and population effect are found to be leading factors in carbon emissions, while energy intensity is found to be reducing the effect. Further, the system-GMM estimates show that ICT and energy intensity positively affect total factor productivity, while with an increase in carbon emission intensity, productivity declines. The study confirms the existence of an inverted N-shaped Kuznets curve in the sector. This present study will contribute to formulating energy and environmental strategies to reduce emissions and promote adopting cleaner energy sources. These efforts will facilitate the attainment of carbon neutrality and enhance energy efficiency within the sector.

SOFIA/HAWC+ Far-infrared Polarimetric Large-area CMZ Exploration Survey. III. Full Survey Data Set

We present the second data release (DR2) of the Far-InfraREd Polarimetric Large-Area CMZ Exploration (FIREPLACE) survey. This survey utilized the Stratospheric Observatory for Infrared Astronomy High-resolution Airborne Wideband Camera plus instrument at 214 μm (E band) at a resolution of 19.″6 to observe thermal polarized dust emission throughout the Central Molecular Zone (CMZ). DR2 consists of observations obtained in 2022 covering the region of the CMZ extending from the Brick to the Sgr C molecular clouds (corresponding to a 1° × 0.°75 region of the sky). We combine DR2 with the first FIREPLACE data release (DR1) to obtain full coverage of the CMZ (a 1.°5 × 0.°75 region of the sky). After applying total and polarized intensity significance cuts on the full FIREPLACE data set, we obtain ∼64,000 Nyquist-sampled polarization pseudovectors. The distribution of polarization pseudovectors confirms a bimodal distribution in the CMZ magnetic field orientations, recovering field components that are oriented predominantly parallel or perpendicular to the Galactic plane. This distribution of orientations is similar to what was observed in DR1 and other studies. We also inspect the magnetic fields toward a set of prominent CMZ molecular clouds (the Brick, Three Little Pigs, 50 and 20 km s−1 clouds, circumnuclear disk, CO 0.02-0.02, and Sgr C), revealing spatially varying magnetic fields having orientations that generally trace the total intensity morphologies of the clouds. We find evidence that compression from stellar winds and shear from tidal forces are prominent mechanisms influencing the structure of the magnetic fields.

What shapes international air transportation in Southern Africa? − The evidence considering the impact of Covid-19

The lack of intra-continental air connectivity in Africa has long been criticized. This paper aims to understand the factors determining intra-regional air transportation in the Southern Africa region and the impact of the COVID-19 pandemic. Firstly, we analyze the geospatial characteristics of the air transport network, airport connectivity, and market structure before and after the pandemic. We also examine the progress of air transport liberalization in Africa and its impact on market structure and airline privatization. We find that the liberalization facilitated market competition and the progress of privatization, but its influence didn’t sustain long. Secondly, based on monthly data at the city level from April 2012 to December 2021, using monthly Total Night-time Light Intensity (TNLI) as a proxy of gross regional product (GRP), we develop a gravity model to empirically investigate the determinants of international air passenger flows within Southern Africa. The analysis shows that the factors promoting air traffic include GRP, air transport liberalization, the presence of low-cost carriers, and airline privatization, while high market concentration and diplomatic disagreements hinder air passenger flows. The pandemic and associated government restriction measures have severely impacted intra-regional air transport connectivity, while the vaccination program has significantly contributed to the recovery of air transportation.

Transition of dome formation to sudden explosive eruptions at Popocatépetl, Mexico: magnetic indicators

Transitions from effusive to explosive activity can increase hazards making it crucial to define early indicators such as changes in the magnetic signals. After more than 80 cycles of crater-dome extrusion and destruction from 1996 on, Popocatépetl volcano (Mexico) experienced changes in its behavior from March 15 to 18 July 2019, when no lava domes were observed. Some of the domes behaved as contained lava flows within the crater floor (pancakes) while others were more irregular-shaped. Activity decreased considerably over this 2019 interval except for the unexpected explosions in March and June, that produced ash plumes reaching up to 14,000 m a.s.l. In order to investigate the causes of the transition from effusive to explosive behavior in March and June, we analyzed the time series from the magnetic monitoring network at Popocatépetl volcano between October 2018 and December 2019. The raw signals were analyzed by weighted differences (WD) based on the elimination of non-local changes from the total intensity values of the geomagnetic field and the discrete-time continuous wavelet transform was used to evaluate the local variations of energy within the time series. The high energy periods (linked to negative magnetic anomalies) are induced by magma ascent associated with movement within the conduit. They indicate that the sudden explosions were due to the ascent of several magma batches that were slowed during ascent and were not able to reach the surface. Changes in the rheology of the lava are linked to the influx of several batches of magma with different compositions as well as to compaction by gas loss when ascending andesitic magma pushed out overlying more viscous degassed magma clearing the conduit, which can explain why these sudden explosions were more energetic. Several geophysical data sets as well as tephra compositions were integrated to support this conclusion. The correlated multiparameters also confirm that geomagnetic volcano monitoring has been essential in understanding the processes that drive the observed changes in eruptive behavior. We present new evidence for the detection of transient events produced by magma ascent and changes in the feeding system of Popocatépetl volcano with wavelet analysis. Detailed vulcanomagnetic processing, especially when it is correlated with other monitoring parameters, provides information on ascending magma and several conduit processes that would otherwise be camouflaged. Ascending batches may precede an eruption but they can also ascend in several pulses indicating how dome growth occurs.

Copper (II) Level in Musts Affects Acetaldehyde Concentration, Phenolic Composition, and Chromatic Characteristics of Red and White Wines.

Copper (II), a vital fungicide in organic viticulture, also acts as a wine oxidation catalyst. However, limited data are currently available on the impact that maximum allowed copper (II) ion doses in wine grapes at harvest can have on aged wine quality. This was the focus of the present study. We investigated the copper (II) effects by producing both white and red wines from musts containing three initial metal concentrations according to the limits set for organic farming. In detail, the influence of copper (II) on fermentation evolution, chromatic characteristics, and phenolic compounds was evaluated. Interestingly, the white wine obtained with the highest permitted copper (II) dose initially exceeded the concentration of 1.0 mg/L at fermentation completion. However, after one year of storage, the copper (II) content fell below 0.2 ± 0.01 mg/L. Conversely, red wines showed copper (II) levels below 1.0 mg/L at the end of fermentation, but the initial copper (II) level in musts significantly affected total native anthocyanins, color intensity, hue, and acetaldehyde concentration. After 12-month aging, significant differences were observed in polymeric pigments, thus suggesting a potential long-term effect of copper (II) on red wine color stability.

Towards an astronomical use of new-generation geodetic observations. I. From the correlator to full-polarization images

The current algorithms used for the calibration and analysis of very long baseline interferometry (VLBI) networks that only use linear polarizers (as is the case of the VLBI Global Observing System, VGOS) do not properly account for instrumental and source-intrinsic polarimetry, which can cause errors in geodetic and astronomical products. We aim to develop a calibration pipeline for VLBI interferometers that observe in a basis of linear polarization, as is the case of VGOS. The products from this pipeline can be used to obtain valuable full-polarization astronomical information from the observed sources, and they can be used to potentially improve the geodetic results. We used the algorithm PolConvert to write the correlation products in a basis of circular polarization that is compatible with the standard VLBI calibration procedures. In addition to this, we implemented a wide-band global fringe-fitting algorithm that accounts for dispersive effects (ionospheric delay) and allows us to perform full-polarization imaging of all the observed sources, covering the whole frequency band of VGOS. We present the outcome of our pipeline applied to a global IVS VGOS epoch of observations and show example imaging results in total intensity and polarization. We also discuss issues encountered during the analysis and suggest points of improvement in the VGOS system for an optimum geodetic and astronomical exploitation of this interferometer.

Isotropic and anisotropic edge detection based on Fourier single pixel imaging

In this paper, we propose a novel edge detection scheme based on Fourier single pixel imaging, capable of realizing both isotropic and anisotropic edge detection. In the scheme, we use a series of specific designed sinusoidal speckle patterns to illuminate the object. The corresponding total intensity of reflective light is then measured by a bucket detector. By performing the inverse Fourier transformation on the bucket detection results, an isotropic or anisotropic edge image of the object could be reconstructed directly. Simulation and experimental results demonstrate that our scheme can capture the isotropic or anisotropic edge images of the object with both direct and indirect line of sight to the object. Our scheme offers the advantages of achieving a clear and high-quality isotropic or anisotropic edge image with only one imaging reconstruction computing operation from sub-Nyquist measurements, which significantly reduces the number of measurements required for single pixel imaging. In addition, our scheme provides the benefits of achieving the single pixel anisotropic edge imaging, allowing one to decide the edges in an arbitrary direction to disappear while preserving the edges in other directions.

Thermal-bioconvection instability in a suspension of phototactic microorganisms heated from below

In this study, we investigate the linear stability of a suspension of motile algae under the combined influence of phototaxis and temperature gradients. The suspension, heated from below and illuminated from above with vertical collimated irradiation, sheds light on the intricate interplay between biological responses and thermal dynamics. The Navier–Stokes equation, thermal energy equation, and cell conservation equation are considered for the mathematical model. In suspension, the upper surface is taken as stress-free, while the lower surface is taken as rigid. The resulting eigenvalue problem, including the bioconvection Rayleigh and thermal Rayleigh numbers, is resolved numerically. Changes in the critical total intensity and Lewis number do not impact the critical threshold of the thermal Rayleigh number; however, they notably influence the critical bioconvection Rayleigh number. The critical total intensity and Lewis number destabilize the suspension. It is observed that heating from below enhances the instability of the layer. At higher temperatures, Rayleigh–Bénard convection dominates bioconvection, resulting in a single convection cell. Neutral curves of linear stability reveal transitions between stationary and oscillatory solutions. The results, validated against established methods, highlight the system’s response to parameters and phenomena such as Hopf bifurcations and limit cycles.

Field evaluation of hydrogen peroxide bath technique for controlling sea lice (Lepeoptheirus spinifer) infestation in snubnose pompano (Trachinotus blochii)

Sea lice infestations can pose significant challenges in the aquaculture sector, affecting fish health and overall production. In the search for effective and eco-friendly solutions, hydrogen peroxide bath treatment has been considered as one of the promising methods. This is the first study to evaluate the field efficacy of hydrogen peroxide bath technique against sea lice infestation on cage-cultured snubnose pompano (Trachinotus blochii). Sea lice was identified as Lepeophtheirus spinifer using morphological description. Naturally-infested snubnose pompano stocked in 2 ×3×2 m3 net cages at 15 fish/cage at the Igang Marine Station of SEAFDEC/AQD, in Guimaras, Philippines were treated in triplicates with two hydrogen peroxide concentrations (1500 and 2000 ppm) in comparison to a control (seawater only) for 20 minutes at 32.8 ± 0.7 ppt and 28.9 ± 0.3 °C and were monitored at 3rd and 7th day post-treatment. The total mean intensity of sea lice, mean intensity per life stages (copepodid, chalimus I, chalimus II, pre-adult I, pre-adult II, adult male and adult female), and the 12-h viability of scraped male and adult female L. spinifer from the treatment groups were evaluated. The total mean intensity of sea lice in the treated groups at 3 day post-treatment was significantly lower than the control group (p<0.001). A possible re-infection of sea lice was observed 7 days post-treatment as explained by the slight increase in the mean intensity in the treated groups. However, no mortalities of pompano were recorded throughout the experiment. In addition, adult female lice were absent in the treated group while adult male lice were only detected in the 1500 ppm treatment group at a very low mean intensity. The viability test also showed that all sea lice were not able to recover after 12 h whereas a 100 % recovery rate was noted in the control group. Results suggest that the 1500 and 2000 ppm hydrogen peroxide concentrations are effective in reducing sea lice infestation on cage-cultured snubnose pompano. However, a long-term effect of hydrogen peroxide treatment on sea lice needs further investigation.

Spectropolarimetric Radio Imaging of Faint Gyrosynchrotron Emission from a CME: A Possible Indication of the Insufficiency of Homogeneous Models

The geo-effectiveness of coronal mass ejections (CMEs) is determined primarily by their magnetic fields. Modeling of gyrosynchrotron (GS) emission is a promising remote sensing technique to measure the CME magnetic field at coronal heights. However, faint GS emission from CME flux ropes is hard to detect in the presence of bright solar emission from the solar corona. With high dynamic-range spectropolarimetric meter wavelength solar images provided by the Murchison Widefield Array, we have detected faint GS emission from a CME out to ∼8.3 R ⊙, the largest heliocentric distance reported to date. High-fidelity polarimetric calibration also allowed us to robustly detect circularly polarized emission from GS emission. For the first time in the literature, Stokes V detection has jointly been used with Stokes I spectra to constrain GS models. One expects that the inclusion of polarimetric measurement will provide tighter constraints on the GS model parameters. Instead, we found that homogeneous GS models, which have been used in all prior works, are unable to model both the total intensity and circular polarized emission simultaneously. This strongly suggests the need for using inhomogeneous GS models to robustly estimate the CME magnetic field and plasma parameters.

Estimating spent fuel burnup with Neutron measurements: A Practical Rule of Thumb Equation

We present a concise equation correlating the burnup of spent nuclear fuel (SF) with the neutron count rate, developed through comprehensive data analysis from Origen-ARP and MCNP codes. This equation is applicable to Fork detectors, commonly used for verifying SF assemblies before their transfer to new storage sites. The detector is assumed to be a helium-3 detector. The reaction rate (RR) in the 3He detector is influenced by Total Neutron Source Intensity (TNSI), net neutron multiplication, and neutron capture during transit to the detector. TNSI emerges as the most influential factor. Two scenarios were explored: one involving pure water and the other with water containing 2000 ppm of boron. The characteristics of the concise equation are also analyzed.

Association between profiles of accelerometer-measured daily movement behaviour and mortality risk: a prospective cohort study of British older adults

ObjectivesWe identified profiles of wake-time movement behaviours (sedentary behaviours, light intensity physical activity and moderate-to-vigorous physical activity) based on accelerometer-derived features among older adults and then examined their association with...

Intelligent Light Emitting Diode Flashing Supplementary Lighting Control Design and Its Big Data Illumination Analysis

Considering the inherent advantages of the Light Emitting Diode (LED) in the field of illumination, this work designs an intelligent supplementary lighting system using LED as the light source. Combining microcontroller and electronic circuit theory, the circuit is built with the microcontroller PIC16F873 as the core control chip. The system utilizes an external 220 V AC-20 V DC conversion power supply, hence operating on a 20 V DC power source. The system consists of four hardware parts: the onboard power supply uses TI-produced TPS54331 as the control chip to achieve voltage conversion; the external signals (flashing and burst flashing signals) are isolated from the microcontroller through an optocoupler circuit; the PWM pulses output from the microcontroller’s RC1/CCP2 pins drive the corresponding switching tubes to achieve the flashing function; the flashing synchronization signal is output externally after optocoupler isolation, and its synchronous output with the flashing signal is achieved through an optocoupler after LED conduction; the circuit is established using TI-produced differential bus transceiver SN65LBC184D to convert the external 485 differential signal to the level signal required by the microcontroller. In the experiment, after completing the hardware design, connecting the LED panel, and debugging the test program, it is found that the designed lighting system has a good supplementary lighting effect. According to the PWM output waveform, the flashing effect meets the design expectations. The Hadoop big data computing platform is introduced. Simulation testing reveals that under no backlight conditions, the system achieves an illumination intensity of around 20 klx at a distance of about 10 meters. With backlight conditions, the system maintains an illumination intensity of around 1.5 klx at a distance of about 10 meters. Further calculations are performed to analyze the variation in foot traffic within the test area’s illumination over 24 hours. The total illumination intensity during different time intervals is compiled, confirming that the system can autonomously adjust the illumination intensity of the area based on changes in foot traffic.