Time Of Sunrise Research Articles

Adjustments of flower opening time and duration in tropical rice (Oryza sativa ssp. indica) landraces in response to heat stress

AbstractBased on our primary database of the flower opening time (FOT) and flower exposure duration (FED) of 1114 rice (Oryza sativa ssp. indica) landraces, we examined the influences of growing season, sunrise time as well as day maximum and minimum temperatures on the anthesis behaviour of indica rice landraces of South and Southeast Asia, flowering in summer and winter in 3 consecutive years (2020–2022). We also compared the FOT and FED on sunny and cloudy days of a small set of landraces, and also during summer and winter. Our data show that rice florets tend to open later in the morning and lengthen the sunrise‐to‐anthesis duration (SAD) on hotter sunny days during tropical summer than during winter and on cloudy days. These findings contradict the widely held conjecture, based on studies conducted at colder latitudes, that rice flowers open earlier in the morning to avoid heat stress. We propose that indica rice landraces are sufficiently adapted to tropical summer because they were selected and bred over millennia to withstand heat stress during tropical summer, so their FOT and SAD are weakly influenced by high day temperatures. However, the significant reduction in FED of these landraces, whose flowers open later in mid‐day, seems to be an adaptive mechanism to avoid longer exposure to rising air temperature approaching day maximum temperature.

Spatiotemporal light exposure modeling for environmental circadian misalignment and solar jetlag.

Light exposure is the most powerful resetting signal for circadian rhythms. The objective of this study was to develop and validate a high-resolution geospatial light exposure model that measures environmental circadian misalignment (or solar jetlag) as the mismatch between the social clock and sun clock, which occurs from geographic variation in light exposure leading to delayed circadian phase from relatively less morning light exposure and greater evening light exposure with increasing westward position within a time zone. The light exposure model (30 m2 spatial resolution) incorporated geospatial data across the United States on time zones, elevation (using Google Earth Engine), sunrise time, and sunset time to estimate solar jetlag scores (higher values indicate higher environmental circadian misalignment). The validation study compared the light exposure model in 2022, which was linked with geocoded residential addresses of n = 20 participants in Boston, MA (eastern time zone position) and Seattle, WA (western time zone position) using a geographic information system, with illuminance values captured from wearable LYS light sensors and with sun times from the Solar Calculator. Western versus eastern positions within a time zone were associated with higher solar jetlag scores from the light exposure model (P < 0.01) and relatively larger differences in sunset time measured using light sensors (social clock) and the Solar Calculator (sun clock) (P = 0.04). We developed and validated a geospatial light exposure model, enabling high spatiotemporal resolution and comprehensive characterization of geographic variation in light exposure potentially impacting circadian phase in epidemiologic studies.

Analyzing socio-environmental determinants of bone and soft tissue cancer in Indonesia

BackgroundThis study is designed to explore the potential impact of individual and environmental residential factors as risk determinants for bone and soft tissue cancers, with a particular focus on the Indonesian context. While it is widely recognized that our living environment can significantly influence cancer development, there has been a notable scarcity of research into how specific living environment characteristics relate to the risk of bone and soft tissue cancers.MethodsIn a cross-sectional study, we analyzed the medical records of oncology patients treated at Prof. Suharso National Referral Orthopedic Hospital. The study aimed to assess tumor malignancy levels and explore the relationships with socio-environmental variables, including gender, distance from the sea, sunrise time, altitude, and population density. Data were gathered in 2020 from diverse sources, including medical records, Google Earth, and local statistical centers. The statistical analyses employed Chi-square and logistic regression techniques with the support of Predictive Analytics SoftWare (PASW) Statistics 18.ResultsBoth bivariate and multivariate analyses revealed two significant factors associated with the occurrence of bone and soft tissue cancer. Age exhibited a statistically significant influence (OR of 5.345 and a p-value of 0.000 < 0.05), indicating a robust connection between cancer development and age. Additionally, residing within a distance of less than 14 km from the sea significantly affected the likelihood of bone and soft tissue cancers OR 5.604 and p-value (0.001 < 0.05).ConclusionsThe study underscores the strong association between age and the development of these cancers, emphasizing the need for heightened vigilance and screening measures in older populations. Moreover, proximity to the sea emerges as another noteworthy factor influencing cancer risk, suggesting potential environmental factors at play. These results highlight the multifaceted nature of cancer causation and underscore the importance of considering socio-environmental variables when assessing cancer risk factors. Such insights can inform more targeted prevention and early detection strategies, ultimately contributing to improved cancer management and patient outcomes.

Analysis of Pre-Seismic Ionospheric Disturbances Prior to 2020 Croatian Earthquakes

We study the sub-ionospheric VLF transmitter signals recorded by the Austrian Graz station in the year 2020. Those radio signals are known to propagate in the Earth-ionosphere waveguide between the ground and lower ionosphere. The Austrian Graz facility (geographic coordinates: 15.46°E, 47.03°N) can receive such sub-ionospheric transmitter signals, particularly those propagating above earthquake (EQ) regions in the southern part of Europe. We consider in this work the transmitter amplitude variations recorded a few weeks before the occurrence of two EQs in Croatia at a distance less than 200 km from Graz VLF facility. The selected EQs happened on 22 March 2020 and 29 December 2020, with magnitudes of Mw5.4 and Mw6.4, respectively, epicenters localized close to Zagreb (16.02°E, 45.87°N; 16.21°E, 45.42°N), and with focuses of depth smaller than 10 km. In our study we emphasize the anomaly fluctuations before/after the sunrise times, sunset times, and the cross-correlation of transmitter signals. We attempt to evaluate and to estimate the latitudinal and the longitudinal expansions of the ionospheric disturbances related to the seismic preparation areas.

Prediction and efficient installation of solar panel using machine learning

Utilizing a comprehensive dataset featuring daily information such as sunrise time, sunset time, minimum and maximum temperatures, this study's primary aim is to ascertain the duration necessary for a solar panel installation to become profitable and reach the breakeven point. Users provide input parameters, including the solar panel area to be installed, location, cost per unit of current, and installation charges. Employing time series analysis and forecasting techniques, the system takes into account various environmental factors, energy generation potential, and local energy prices. The ultimate goal is to predict when the cumulative income from the solar panel installation will surpass the initial installation costs, facilitating an estimation of the point at which the solar panel system will break even and commence generating a net profit. This solar panel profitability analysis holds considerable significance individuals and organizations for contemplating investments in renewable energy. It equips stakeholders with the information required to make informed decisions regarding the feasibility and financial viability of solar panel installations at specific locations. This, in turn, promotes a sustainable and cost-effective transition to renewable energy sources, aligning with the broader goal of reducing our reliance on non-renewable energy and fostering environmentally responsible practices.

Effects of groundwater evaporation on the natural recharge to groundwater lenses residing in coastal dunes in Southern Central Vietnam

Groundwater lenses in the coastal dunes along the South Central coast of Vietnam are often of shallow table. The lithologic composition of the vadose zone in these areas is mainly fine to medium-grained sand, characterised by high porosity. The vegetation is sparse, the annual time of sunrise is long, the air temperature and surface evaporation are high. The above-mentioned conditions are favourable for the evaporation of the groundwater. This study utilised direct evaporation measurement by Lysimeter (LS) according to the principle of water balance. The LS measurement is designed to simulate the groundwater level at a depth of 0.9 m to monitor groundwater loss due to evaporation corresponding to the conditions of natural climate and the vadose zones. Monitoring results showed that the total amount of groundwater evaporation in 2022 at three stations Da Nang, Phu Yen and Binh Thuan is 259.9, 335.6, and 377.0 mm, respectively. With the assumed groundwater level at a depth of 0.9 m, the annual amount of groundwater evaporation has caused the reduction in the groundwater level in the aquifer in Da Nang, Phu Yen and Binh Thuan by 0.64, 0.78, and 0.92 m, respectively.

Ionospheric Vertical Correlation Distance Calculation Based on COSMIC Electron Density Profile Data

AbstractBackground error covariance is an important part of ionospheric assimilation and contains correlation information of the ionospheric background field and error information of the model background field, determines the influence degree of observations on models, and controls the vertical electron density distribution of assimilation results. For more accurate background error covariance determination along the ionosphere vertical direction, we used Constellation Observing System for Meteorology Ionosphere and Climate occultation electron density profile data for vertical correlation distance calculation considering IRI 2016 model errors. The vertical direction correlations are asymmetrical above and below the reference altitude, and with increasing altitude, the vertical correlation distance growth rate may decline or remain unchanged. There are correlation differences in different solar activity years, varying with local time, geomagnetic latitude, and altitude. The vertical correlation distances in high‐solar activity years are greater than that in low‐solar activity years. The correlation distances difference at different times decreases with latitude, with the largest correlation distances at low latitudes. The nighttime distances vary slightly with latitude, while the sunrise correlation distances vary the most relative to other periods. At the same altitude, the correlation distances in the daytime low‐latitude region are the smallest overall, while the correlation distances between the daytime mid‐latitude region and sunrise time are the largest. The point where vertical correlation distances growth stabilize may be correlated with ionospheric hmF2 and upper transition. The IRI model is the most widely used background model in ionospheric assimilation, and the study results could facilitate more accurate vertical background error covariance for ionospheric assimilation.

Determination of Hourly Distribution of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) Using Sex Pheromone and Ultraviolet Light Traps in Protected Tomato Crops

Tuta absoluta (Meyrick), a leafminer that damages tomato leaves, terminal buds, flowers, and fruits, is a destructive tomato pest and is responsible for 80–100% of tomato yield losses globally. Different insect species have different courtship responses and phototropic flight rhythms. Improving the trapping effects of the sex pheromone and light traps is important for constructing an IPM system for T. absoluta. The present study explored the hourly distribution of T. absoluta adults caught by the sex pheromone (on the ground) and UV light (380 nm) traps in greenhouses over 24 h. The responses of males to sex pheromone (false female) lures were detected at dawn and early morning. The responses lasted for 3 h, from 05:30 (1 h before sunrise) to 08:30 (2 h after sunrise), and 95.8% of the males were caught during this period. The peak of the male responses to the sex pheromone was detected at 07:30 (from 06:30 to 07:30, 1 h after sunrise), and 80.8% of the males were caught during this period. The flight of male (proportion of 54.3%) and female (45.7%) adults toward the UV light traps occurred from 19:30 (time of sunset) to 06:30 (time of sunrise), lasted for 11 h, and exhibited a scotophase rhythm; 97.4% of the adults were caught during this period. The peak of adults flying toward the UV light traps occurred at 21:30 (from 20:30 to 21:30, 2 h after sunset). The rhythms of males’ responses to the sex pheromone and of the adults’ flight toward the UV lights can help to reveal the mechanisms of chemotactic and phototactic responses and may play a significant role in constructing an IPM system for this pest.

Migratory Daily Departure Times of Chinese Sparrowhawks (Accipiter soloensis) and Gray-Faced Buzzards (Butastur indicus) in Taiwan

ABSTRACT The strategies that migratory raptors adopt during migration reveal their long-term adaptations to different environments along their migration routes and of their stopover sites. We recorded the daily departure time of Chinese Sparrowhawks (Accipiter soloensis) and Gray-faced Buzzards (Butastur indicus) during their southward migration in autumn 2019 at Kenting National Park, southern Taiwan, and 2020 in Yushan National Park, central Taiwan. At both watchsites, Gray-faced Buzzards started their migration journey about 1 hr earlier than Chinese Sparrowhawks. After adjusting for the local sunrise time, the first daily appearance time of Gray-faced Buzzards (–2.5 ± 9.3 min) was significantly earlier than that of Chinese Sparrowhawks (47.0 ± 29.3 min) by about 50 min at Kenting National Park. Though they initiated migration later in morning at montane stopover sites in Yushan National Park, the same trend was observed and with even greater difference, about 70 min. These results indicate that these two species migrate in different daily periods and suggest that Chinese Sparrowhawks might choose to exploit stronger thermal uplifts in September before leaving the island, as they started migration later in the morning. In contrast, Gray-faced Buzzards, a species more dependent on soaring-gliding flight, set off earlier in the day, probably to take advantage of stronger northeastern tailwinds that begin in October. We conclude that the prevailing monthly wind conditions, particularly influenced by the northeast monsoons, shape the different diurnal migration times of these two raptors migrating along the East-Asian Oceanic Flyway.

Enhancing thermal performance and sustainability parabolic trough concentrator systems in Djelfa's solar-integrated urban design

In this study, the coldest days of 2022 in the Djelfa region, Algeria, were determined using astronomical and climatic data. The timing of sunrise, sunset, and duration of sunlight, as well as changes in solar radiation intensity and air temperature, were analyzed. By converting solar radiation into heat and solving differential equations, the study examined water exit temperature, thermal energy, and total yield as outputs of a renewable energy converter. The effect of different glass coverings on these outputs was also investigated. The coldest day in 2022 was found to be the first day of January, with nine hours and 43 minutes of sunlight, a maximum solar radiation intensity of 670.34 MW/m?, and a maximum air temperature of 16.9?C. The outputs of the solar center followed a parabolic pattern for the first two parameters and increased over time for the remaining outputs, regardless of the glass type. However, using glass with a high emission coefficient, such as clear monochromatic glass, resulted in the highest values for the outputs: 52.57?C, 7.5 kW, 162 MW, and 70.62%. By understanding solar energy conversion and thermal behavior, the study contributes to energy-efficient designs and renewable integration, aiding in sustainable urban development. Findings can inform decision-makers in optimizing material selection, promoting resilient infrastructure, and advancing sustainable practices for a low-carbon future.

세종 시대 서울 기준 시각법의 성립과 그 의의

Being helped by the research on the calendrical calculation system during the first fourteen years of king Sejong period (r.1419-1450), in around 1434 Joseon 朝鮮 astronomers could calculate four time-units, year, month, day, and hour. However, due to the obligation of ‘upholding the first month and first day’ (奉正朔) which is forced by the Tribute-investiture (朝貢冊封) relationship, in Joseon the vassal kingdom, they could not use the calendrical days (曆日, year, month, and day) according to the calculation results based on the location of Seoul. The calendrical days ought to be accord with those of the Ming China, the dominant kingdom, whose standard point located at Nanjing 南京. The local time which was measured in real time, however, was not confined by the obligation. In Joseon, they could use their local time which was measured on the meridian of Seoul. And they were able to calculate and use those local times, the time of sunrise and sunset (日出入時刻) and the length of day and night (晝夜刻), on Seoul’s latitude, and which were distinct from those of Ming China. It was Joseon’s local time that Jagyeongnu (自擊漏, automatic striking clepsydra) automatically calibrated and struck.

Circadian phase advances in children during camping life according to the natural light-dark cycle

BackgroundIt is known that the circadian rhythm phase in adults can be advanced in a natural light-dark cycle without electrical lighting. However, the effect of advanced sleep-wake timing according to the natural light-dark cycle on children’s circadian phase is unclear. We investigated the effects of approximately 2 weeks of camping life with little access to artificial lighting on children’s circadian phases. We also conducted an exploratory examination on the effects of wake time according to natural sunrise time on the manner of the advance of their circadian phases.MethodsTwenty-one healthy children (mean ± SD age, 10.6 ± 1.4 years) participated in a camping program with wake time (4:00) being earlier than sunrise time (EW condition), and 21 healthy children (10.4 ± 1.1 years) participated in a camping program with wake time (5:00) being almost matched to sunrise time (SW condition). Salivary dim light melatonin onset (DLMO) before the camping program and that after approximately 2 weeks of camping were compared.ResultsDLMO was advanced by approximately 2 h after the camping program compared with the circadian phase in daily life in both conditions. In addition, the advances in DLMO were significantly correlated with mid-sleep points before the camp in both conditions (EW: r = 0.72, p < 0.01, SW: r = 0.70, p < 0.01). These correlations mean that the phase advance was greater for the children with delayed sleep habits in daily life. Furthermore, in the EW condition, mean DLMO after the camp (18:09 ± 0:33 h) was earlier than natural sunset time and there was no significant decrease in interindividual variability in DLMO. On the other hand, in the SW condition, mean DLMO after the camp (18:43 ± 0:20 h) matched natural sunset time and interindividual variability in DLMO was significantly lower than that before the camp.ConclusionsCamping with advanced sleep and wake timing under natural sunlight advances children’s circadian phases. However, DLMO earlier than sunset in an early waking condition may lead to large interindividual variability in the circadian rhythm phase.

Spatiotemporal exposure modeling of environmental circadian misalignment

Background and Aim: Light exposure is the most powerful resetting signal for circadian rhythms. Environmental circadian misalignment (ECM) occurs from geographic variation in light exposure due to location within a time zone (delayed circadian phase from less morning and greater evening light exposure moving west in a time zone). The aim of this study was to develop and validate the first-ever nationwide spatiotemporal exposure model of ECM in the US. Methods: For all US census tracts, the ECM exposure model incorporated elevation (in meters) and the average difference (in minutes) in sunrise time and sunset time between the census tract center of population and the eastern-most time zone boundary. Higher ECM exposure values indicate higher circadian misalignment due to higher elevation (fewer obstructions/extended field of view) and larger differences in sunrise and sunset times. Spearman correlation coefficients and multivariable linear regression adjusting for age, sex, race, ethnicity, median household income, and population density were used to validate the ECM exposure model with census tract-level prevalence of obesity (2016-2019) (known outcome associated with circadian misalignment). Results : Among the 60,943 census tracts included in this study, obesity prevalence was 32.62%. ECM exposure was positively correlated with obesity prevalence, with the strongest correlation in the Eastern time zone (rs=0.44, p&amp;#x3c;0.01). The highest vs. lowest ECM quintile was associated with higher obesity prevalence in the Eastern (adjusted β=6.00, 95% CI 6.68, 7.11) and Central time zones (adjusted β=2.85, 95% CI 2.62, 3.09), which are the US time zones characterized by the largest east-to-west distance (i.e., opportunity for ECM). Conclusions: We developed and validated a US nationwide spatiotemporal ECM exposure model, which can be used for exposure assessment in epidemiologic studies to enable comprehensive characterization of geographic variation in light exposure potentially impacting circadian phase. Keywords: light exposure; circadian misalignment; exposure model

A Systematic Study of 7 MHz Greyline Propagation Using Amateur Radio Beacon Signals

This paper investigates 7 MHz ionospheric radio wave propagation between pairs of distant countries that simultaneously lie on the terminator. This is known as greyline propagation. Observations of amateur radio beacon transmitters recorded in the Weak Signal Propagation Reporter (WSPR) database are used to investigate the times of day that beacon signals were observed during the year 2017. The WSPR beacon network consists of thousands of automated beacon transmitters and observers distributed over the globe. The WSPR database is a very useful resource for radio science as it offers the date and time at which a propagation path was available between two radio stations, as well as their precise locations. This paper provides the first systematic study of grey-line propagation between New Zealand/Eastern Australia and UK/Europe. The study shows that communications were predominantly made from the United Kingdom (UK) to New Zealand at around both sunset and sunrise times, whereas from New Zealand to the UK, communication links occurred mainly during UK sunrise hours. The lack of observations at the UK sunset time was particularly evident during the UK summer. The same pattern was found in the observations of propagation from Eastern Australia to UK, and from New Zealand and Eastern Australia to Italy and the surrounding regions in Europe. The observed asymmetry in reception pattern could possibly be due to the increase in electromagnetic noise across Europe in the summer afternoon/evening from thunderstorms.

New approach towards mitigating photovoltaic panels soiling by dew flowing.

Soiling has a crucial importance regarding its impact mainly for countries that have high soiling levels, dust storms, water scarcity and a great solar energy potential as the case of Morocco. Soiling mitigation is therefore mostly required during spring, due to higher pollen concentration, and summer, due to the lack of heavy precipitation. In this work, systematic measurements of soiling ratio were made in Rabat, city of north-western Morocco, during almost 1year. Soiling has been evaluated considering the effect of dual-axis tracking that was compared to photovoltaic (PV) on fixed structure. A soiling rate of about 0.22%/day has been found for static PV while only 0.1% was found for PV on tracker. An additional approach of cleaning has been proposed in this paper which aims to use dew water. Using glass samples that were exposed to real environmental conditions, similar to the exposure conditions of PV panels, the soiling ratio was determined. At sunrise time, the subsequent change of the glass sample, from the horizontal position at night into the position of 30° tilt angle during the day, is performed to promote dew flow by the force of gravity acting on the droplets of dew. It has been found that relying only on the change of tilt angle, the average soiling losses were only 3.8% compared with 11.8% for fixed PV. This approach can reduce soiling similarly to solar trackers.

Using a ray tracing program to calculate sunrise times over a digital terrain model based visible horizon using a simplified atmospheric model, part II

In a previous paper we compared observations to calculated values of the sunrise times for one place in Jerusalem. It was shown that the sunrise over the actual physical horizon could be modeled to an accuracy of about ±15 s for most of the year. Success of those calculations suggested that terrain modeling was the most important factor in obtaining this result. To investigate this point, we repeated our calculations using the ray tracing method and simplified atmosphere developed by Siebren Van der Werf, whose atmospheric model is easily applied to other places in the world. Our results show that the new calculation method maintained our requirement of ±15 s accuracy (required for publication of sunrise time tables, critical for daily Jewish observances worldwide). Standard formulas for atmospheric refraction produce approximately the same results even for near horizon zenith angles. For portions of the year where low altitude inversions are especially important, e.g., during those days associated with maximum radiative cooling, these additional atmospheric effects can be effectively modeled in a very simple way.

Does Daylength Affect Sleep and Mental Health Symptoms during Behavioral Interventions for Insomnia?

ABSTRACT Background Approximately 11–33% of Australian adults experience Insomnia Disorder, which is associated with higher rates of psychiatric comorbidities, and lower quality of life. Non-pharmacological interventions are the front-line treatments for insomnia. Despite the known impact of light on the sleep/wake cycle via the circadian system, it is not yet known whether seasonal variations in environmental light levels (i.e., daylength) influence treatment outcome. We aimed to determine whether seasonal differences in daylength influenced baseline symptoms of Insomnia Disorder or treatment outcome. Participants One hundred treatment-seeking individuals with Insomnia Disorder (age: 49.3 ± 14.4y, range: 18–82 years; 58 F) enrolled in a Randomized Control Trial in Australia over a 29-month period. Methods Clients completed a seven-session behavioral intervention for insomnia over a maximum of 12 weeks. Individuals completed questionnaires assessing insomnia symptoms, diurnal preference, depression and anxiety symptoms, and daily sleep diaries. Objective rest/activity patterns were monitored using wrist actigraphy for the duration of the treatment period. Results Baseline daylength, sunset and sunrise times, and change in daylength over treatment, were not related to baseline insomnia severity or mental health symptoms. However, longer daylength at baseline predicted greater improvements in insomnia symptoms and anxiety, but not depression, symptoms. These improvements were also associated with later sunset and/or earlier sunrise at baseline. Conclusions Our results show, greater treatment-related improvements in subjective sleep and mental health symptoms during spring and summer months. This suggests that daylength could have a role to play in the outcomes of a behavioral insomnia treatment. Future research is needed to provide recommendations.

Seasonal Sleep Variations and Their Association With Meteorological Factors: A Japanese Population Study Using Large-Scale Body Acceleration Data.

Seasonal changes in meteorological factors [e.g., ambient temperature (Ta), humidity, and sunlight] could significantly influence a person's sleep, possibly resulting in the seasonality of sleep properties (timing and quality). However, population-based studies on sleep seasonality or its association with meteorological factors remain limited, especially those using objective sleep data. Japan has clear seasonality with distinctive changes in meteorological variables among seasons, thereby suitable for examining sleep seasonality and the effects of meteorological factors. This study aimed to investigate seasonal variations in sleep properties in a Japanese population (68,604 individuals) and further identify meteorological factors contributing to sleep seasonality. Here we used large-scale objective sleep data estimated from body accelerations by machine learning. Sleep parameters such as total sleep time, sleep latency, sleep efficiency, and wake time after sleep onset demonstrated significant seasonal variations, showing that sleep quality in summer was worse than that in other seasons. While bedtime did not show clear seasonality, get-up time varied seasonally, with a nadir during summer, and positively correlated with the sunrise time. Estimated by the abovementioned sleep parameters, Ta had a practically meaningful association with sleep quality, indicating that sleep quality worsened with the increase of Ta. This association would partly explain seasonal variations in sleep quality among seasons. In conclusion, Ta had a principal role for seasonality in sleep quality, and the sunrise time chiefly determined the get-up time.

Performance Enhancement of Solar Photovoltaic Cell

This paper consists analysis on performance enhancement of solar photovoltaic cell by using reflecting and cooling system. The performance of PV (photovoltaic) module is strongly dependent on its surface temperature and solar radiation strikes on PV panel. It is necessary to study possible way for maintaining the appropriate temperature for solar panels and make system that will help to strikes maximum solar radiation on panel. High solar radiation and ambient temperature lead to an elevated photovoltaic cell operating temperature, which affects its lifespan and power output adversely. To enhance the electrical performance of the PV module we make one system which consists of two mirrors as a reflector placing beside solar panel and cooling system consists of pipe placed on upper area of solar panel. At time of sunrise and sunset low solar radiation is fall on solar panel, so reflecting system increase the intensity of solar radiation fall on solar panel. At noon time or afternoon the temperature of solar panel is increases it will decrease the efficiency of solar panel to minimize that cooling system is introduced that controlled the surface temperature.

Diel, lunar and seasonal vertical migration in the deep western Gulf of Mexico evidenced from a long-term data series of acoustic backscatter

The pattern of zooplankton migration has been investigated in the water column from 120 to 1300 m depth using the backscatter strength signal (Sv) provided by Acoustic Doppler Current Profilers (operating at 300 kHz and 76.8 kHz), from a 10-year high-frequency mooring time series (2008–2018) in the deepwater region of the western Gulf of Mexico (GoM). This analysis was complemented with in-situ thermohaline data, model derived data, as well as one-month deployment glider-derived oceanographic information.The overall Sv time series presents a marked circadian cycle at 12 and 24 h associated with the well-known Diel Vertical Migration (DVM) motion performed by the zooplankton community. The signal analysis reveals the existence of two main layers (a shallow layer between the surface to about 100 m and an intermediate one from 400 m to 600 m), where the abundance of scatterers is the highest. Both layers exhibit a seasonal -but different- modulation of the DVM, with peaks in backscatter at ~ 200 m in winter but at ~ 400 m depth in summer; with no seasonal variability below 800 m. The migration pattern differed between depths, and relative to density, dissolved oxygen concentration, mixed layer depth and net primary production. Density plays a major role in the upper 600 m limiting the depth of the different migration patterns, whereas oxygen concentration reveals to be the best single predictor of resident depth of non-migrating species in the deeper layer. A relationship was found between the migration patterns and the moon and sun position, since the migration patterns were finely tuned to the timing of sunrise and sunset. The shallowest group (0–500 m) begins to descend about two hours before sunrise, and starts to rise about one hour before sunset. The amount of light penetrating the ocean when the sun altitude is greater than 35° seems to be the triggering mechanism of DVM for the mesopelagic species in the GoM. A wavelet analysis applied to the backscatter signal reveals a close relation between migratory patterns and the moon’s periodicity in the layer 1000–1200 m, rather than in the upper water column. Based on previous studies of the biological community of the deepwater region of the GoM, the migration patterns likely reflect the presence of a seasonally-varying community of scatterers in the surface layer, partially-migratory and strongly migratory taxa in the mesopelagic layer, resident taxa associated with the minimum oxygen layer, and a deeper community which may migrate in response to the lunar cycle.