scholarly journals WATER-CONTAINING ABILITY OF COTTON LEAVES UNDER DIFFERENT TEMPERATURE CONDITIONS

2019 ◽  
pp. 164-166
Author(s):  
Alisher Muradullaevich Muradullaev
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Water Holding Capacity ◽  
Relative Resistance ◽  
Cotton Variety ◽  
Temperature Conditions ◽  
Control Option ◽  
Air Temperatures ◽  
Water Holding

This article presents the results of studies on the change of the water-holding ability in leaves of some varieties and lines of cotton under the influence of various high air temperatures (I control option from +24.6 to + 35.4 °C; II option - from +36.4 to +45, 1 °C; III option - from +39.5 to + 48.4 °C). At a high air temperature of + 48.4 °C, the water-holding capacity of the leaves in varieties Surkhan-14, Istiklol-14, Bukhara-102 was 26.2; 24.6; 26.4%, which indicates the relative resistance of these varieties to high air temperatures. KEYWORDS: cotton, variety, line, high air temperature, relative humidity, water holding ability.

scholarly journals Quantifying the Independent Influences of Land Cover and Humidity on Microscale Urban Air Temperature Variation in Hot Summer: Methods of Path Analysis and Genetic SVR

Atmosphere ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1377
Author(s):  
Weifang Shi ◽  
Nan Wang ◽  
Aixuan Xin ◽  
Linglan Liu ◽  
Jiaqi Hou ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Land Cover ◽  
Path Analysis ◽  
Temperature Variation ◽  
Direct Effect ◽  
Air Temperature ◽  
Urban Areas ◽  
Support Vector ◽  
Urban Air ◽  
Air Temperatures

Mitigating high air temperatures and heat waves is vital for decreasing air pollution and protecting public health. To improve understanding of microscale urban air temperature variation, this paper performed measurements of air temperature and relative humidity in a field of Wuhan City in the afternoon of hot summer days, and used path analysis and genetic support vector regression (SVR) to quantify the independent influences of land cover and humidity on air temperature variation. The path analysis shows that most effect of the land cover is mediated through relative humidity difference, more than four times as much as the direct effect, and that the direct effect of relative humidity difference is nearly six times that of land cover, even larger than the total effect of the land cover. The SVR simulation illustrates that land cover and relative humidity independently contribute 16.3% and 83.7%, on average, to the rise of the air temperature over the land without vegetation in the study site. An alternative strategy of increasing the humidity artificially is proposed to reduce high air temperatures in urban areas. The study would provide scientific support for the regulation of the microclimate and the mitigation of the high air temperature in urban areas.

INFLUENCE OF TEMPERATURE AND HUMIDITY ON THE EMERGENCE BEHAVIOUR OF ANAX JUNIUS (ODONATA: AESHNIDAE)

1973 ◽  
Vol 105 (7) ◽  
pp. 975-984 ◽  
Author(s):  
Robert Trottier
Keyword(s):  
Relative Humidity ◽  
Water Temperature ◽  
Air Temperature ◽  
Water Surface ◽  
Average Speed ◽  
Anax Junius ◽  
Air Temperatures ◽  
Stage 4 ◽  
Temperature And Humidity ◽  
Three Stages

AbstractEmergence from the water of Anax junius Drury normally occurred after sunset. The onset was affected independently by water temperature and air temperature; low water temperature and high air temperature delayed the onset of emergence. In the field, the net vrtical distance travelled above the water, before ecdysis, was positively correlated with air temperature. In the laboratory, the vertical distance travelled above the water was greatest when air and water temperatures were approximately the same. The average speed of climbing to the first resting position above the water surface was faster at high than low water temperature, but the average speed of climbing from there to the final position, where ecdysis occurred, was reduced due to the effects of air temperature and humidity. Air temperatures below 12.6 °C were found to retard ecdysis and larvae returned to the water and emerged early the following day making the final process of emergence and ecdysis diurnal instead of nocturnal. The duration of ecdysis was shorter at high than low air temperatures and only the first three stages, as arbitrarily defined, were longer at low than high relative humidity; stage 4, shortened with low relative humidity. This study shows that A. Junius, emerging from the water is affected at first by the temperature experienced when submerged, but it becomes gradually and cumulatively affected by air temperature and humidity while climbing to the ecdysial position and moulting.

scholarly journals Variation of Frost Roughness on a Flat Plate Under Forced Convection

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Tongxin Zhang ◽  
Dennis L. O’Neal ◽  
Stephen T. McClain
Keyword(s):  
Relative Humidity ◽  
Surface Temperature ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Mean Square ◽  
Empirical Correlations ◽  
Testing Conditions ◽  
Air Temperatures ◽  
Photogrammetric Method ◽  
Grain Roughness

Abstract Experiments were conducted on a cold flat aluminum plate to characterize the variation of frost roughness over both time and location on the surfaces. The testing conditions included air temperatures from 8 to 16 °C, wall temperatures from −20 to −10 °C, relative humidities from 60 to 80%, and air velocities from 0.5 to 2.5 m/s. Each test lasted 2 h. A 3D photogrammetric method was employed to measure the variation in frost root-mean-square height and skewness by location and time. These data were used to develop the equivalent sand-grain roughness for the frost at different locations and time. The experimental results showed that frost roughness varied by location and changed with time. For the environmental conditions in this study, relative humidity and air temperature were the most important factors determining changes in the peak frost roughness. For example, at an air temperature of 12 °C and a surface temperature of −15 °C, the frost roughness peaked at about 40 min for a relative humidity of 80% and 90 min for a relative humidity of 60%. Empirical correlations were provided to describe the relationships between the environmental conditions and the appearance of the peak frost roughness.

scholarly journals Wet-Bulb Temperature from Relative Humidity and Air Temperature

2011 ◽  
Vol 50 (11) ◽  
pp. 2267-2269 ◽  
Author(s):  
Roland Stull
Keyword(s):  
Gene Expression ◽  
Relative Humidity ◽  
Sea Level ◽  
Air Temperature ◽  
Mean Absolute Error ◽  
Gene Expression Programming ◽  
Absolute Error ◽  
Sea Level Pressure ◽  
Air Temperatures ◽  
Low Humidity

AbstractAn equation is presented for wet-bulb temperature as a function of air temperature and relative humidity at standard sea level pressure. It was found as an empirical fit using gene-expression programming. This equation is valid for relative humidities between 5% and 99% and for air temperatures between −20° and 50°C, except for situations having both low humidity and cold temperature. Over the valid range, errors in wet-bulb temperature range from −1° to +0.65°C, with mean absolute error of less than 0.3°C.

Modeling of Basil Leaves Drying by GA–ANN

2013 ◽  
Vol 9 (4) ◽  
pp. 393-401 ◽  
Author(s):  
Amin Taheri-Garavand ◽  
Shahin Rafiee ◽  
Alireza Keyhani ◽  
Payam Javadikia
Keyword(s):  
Neural Network ◽  
Genetic Algorithm ◽  
Relative Humidity ◽  
Moisture Content ◽  
Air Temperature ◽  
High Accuracy ◽  
Air Velocity ◽  
Feed Forward Neural Network ◽  
Air Temperatures ◽  
Hidden Layer

AbstractIn this research, the experiment is done by a dryer. It could provide any desired drying air temperature between 20 and 120°C and air relative humidity between 5 and 95% and air velocity between 0.1 and 5.0 m/s with high accuracy, and the drying experiment was conducted at five air temperatures of 40, 50, 60, 70 and 80°C and at three relative humidity 20, 40 and 60% and air velocity of 1.5, 2 and 2.5 m/s to dry Basil leaves. Then with developed Program in MATLAB software and by Genetic Algorithm could find the best Feed-Forward Neural Network (FFNN) structure to model the moisture content of dried Basil in each condition; anyway the result of best network by GA had only one hidden layer with 11 neurons. This network could predict moisture content of dried basil leaves with correlation coefficient of 0.99.

scholarly journals The impact of indoor air temperature on the executive functions of human brain and the physiological responses of body

2019 ◽  
Vol 9 (1) ◽  
pp. 55-64 ◽  
Author(s):  
Ali Mohammad Abbasi ◽  
Majid Motamedzadeh ◽  
Mohsen Aliabadi ◽  
Rostam Golmohammadi ◽  
Leili Tapak
Keyword(s):  
Executive Functions ◽  
Human Brain ◽  
Air Temperature ◽  
Physiological Responses ◽  
Heart Beat ◽  
Temperature Conditions ◽  
Beat Rate ◽  
Air Temperatures ◽  
Heart Beat Rate ◽  
The Impact

Background: This study aimed to investigate the effect size (ES) of air temperature on the executive functions of human brain and body physiological responses. Methods: In this empirical study, the participants included 35 male students who were exposed to 4 air temperature conditions of 18°C, 22°C, 26°C and 30°C in 4 separate sessions in an air conditioning chamber. The participants were simultaneously asked to take part in the N-backtest. The accuracy, electrocardiogram (ECG) signals and the respiration rate were recorded to determine the effect of air temperature. Results: Compared to moderate air temperatures (22°C), high (30°C) and low (18°C) air temperatures had a much more profound effect on changes in heart beat rate, the accuracy of brain executive functions and the response time to stimuli. There were statistically significant differences in the accuracy by different workload levels and various air temperature conditions(P<0.05). Although the heart beat rate index, the ratio between low frequency and high frequency (LF/HF), and the respiratory rate were more profoundly affected by the higher and lower air temperatures than moderate air temperatures (P<0.05), this effect was not statistically significant, which may be due to significant reduction in the standard deviation of normal-to normal intervals (SNND) and the root of mean squared difference between adjacent normal heart beat (N-N) intervals (RMSSD) (P>0.05). Conclusion: The results confirmed that the unfavorable air temperatures may considerably affect the physiological responses and the cognitive functions among indoor employees.Therefore, providing them with thermal comfort may improve their performance within indoor environments.

scholarly journals Effect of drying temperature on quality of β-glucan in white oat grains

2012 ◽  
Vol 32 (4) ◽  
pp. 775-783 ◽  
Author(s):  
Leandro da Conceição Oliveira ◽  
Maurício Oliveira ◽  
Volnei Luiz Meneghetti ◽  
Simone Mazzutti ◽  
Luciane Maria Colla ◽  
...  
Keyword(s):  
Moisture Content ◽  
Water Retention ◽  
Water Holding Capacity ◽  
Water Retention Capacity ◽  
Drying Process ◽  
Retention Capacity ◽  
Air Temperatures ◽  
Water As Solvent ◽  
Harvest Moisture ◽  
Water Holding

Oats have received attention because of their nutritional characteristics, especially their high-quality content of β-glucan. The drying process reduces water content; therefore they can be preserved for long periods. However, high-temperature drying process may affect the physical, chemical, and functional properties of the grains. The objective of this study was to evaluate the effect of different drying temperatures on β-glucan quality in oat grains. Grains of oats (Avena sativa, L.), cultivar Albasul, harvested at harvest moisture content of 23% were submitted to stationary drying at air temperatures of 25, 50, 75, and 100 ºC until they reached 13% moisture content. The β-glucan content was determined in samples of oat grains and extraction was performed using water as solvent at 90 ºC. The β-glucan extract was evaluated for water holding capacity, water retention capacity, capacity of displacement, and gelation properties. Stationary of oat grains at air temperatures above 25 ºC decreased the water holding capacity, whereas the content of β-glucan and the water retention capacity of β-glucan extract was affected at temperatures above 50 ºC. Physical changes such as increased gelation capacity of the β-glucan extract occurred following drying at air temperature over 75 ºC.

scholarly journals Reducing misclassified precipitation phase in conceptual models using cloud base heights and relative humidity to adjust air temperature thresholds

2021 ◽  
Author(s):  
Lic James M. Feiccabrino
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Conceptual Models ◽  
Phase Changes ◽  
Cloud Base ◽  
Temperature Threshold ◽  
Air Temperatures ◽  
Low Cloud ◽  
Precipitation Phase ◽  
Cloud Base Height

Abstract In cold region, conceptual models assigned precipitation phase, liquid (rain) or solid (snow), cause vastly different atmospheric, hydrological, and ecological responses, along with significant differences in evaporation, runoff, and infiltration fates for measured precipitation mass. A set air temperature threshold (ATT) applied to the over 30% annual precipitation events occurring with surface air temperatures between −3 and 5 °C resulted in 11.0 and 9.8% misclassified precipitation in Norway and Sweden, respectively. Surface air temperatures do not account for atmospheric properties causing precipitation phase changes as snow falls toward the ground. However, cloud base height and relative humidity (RH) measured from the surface can adjust ATT for expected hydrometeor-atmosphere interactions. Applying calibrated cloud base height ATTs or a linear RH function for Norway (Sweden) reduced to 4.3% (2.8%) and 14.6% (8.9%) misclassified precipitation, respectively. Cloud base height ATTs had lower miss-rates with low cloud bases, 100 m in Norway and 300 m in Sweden. Combining the RH method with cloud base ATT in low cloud conditions resulted in 16.1 and 10.8% reduction in misclassified precipitation in Norway and Sweden, respectively. Therefore, the conceptual model output should improve through the addition of available surface data without coupling to an atmospheric model.

Variação Espaço-Sazonal Termohigrométrica do Parque Urbano Mãe Bonifácia pelo Método da Krigagem

2017 ◽  
Vol 18 (3) ◽  
pp. 252
Author(s):  
Jonathan Willian Zangeski Novais ◽  
Rodrigo Lemos Gil ◽  
Fabricia Cristina Lemos Melo ◽  
Levi Pires de Andrade ◽  
Osvaldo Alves Pereira ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Rainy Season ◽  
Dry Period ◽  
Local Climate ◽  
Rainy Period ◽  
Average Temperature ◽  
Air Temperatures ◽  
The City ◽  
Possible Cause

Parques urbanos servem como áreas de lazer e práticas de exercício, levando a preocupação do conforto térmico de seus usuários. O Parque Mãe Bonifácia, objeto deste estudo, encontra-se na cidade de Cuiabá-MT, sendo um fragmento de cerrado urbano, sofrendo com toda a sazonalidade do clima local, tendo períodos de seca rigorosa e períodos com precipitação. Assim, o objetivo deste trabalho foi fazer uma análise da variação espaço-sazonal termohigrométrica pelo método da krigagem do referido Parque. Foram feitas medidas mensais de temperatura do ar e umidade relativa do ar nos horários entre às 10 e 12 horas. No período seco, as médias de temperatura do ar foram de 33,44 oC, já a média de temperatura para o período chuvoso foi de 31,09 oC. A média de umidade relativa do período seco foi de 43,34% e para período chuvoso 68,71%. Como resultado se percebeu a influência do entorno no parque, sendo as menores temperaturas do ar e maiores umidades relativas do ar as que ocorrem na região central do parque. Os ajustes dos semivariogramas foram considerados satisfatórios para 3 dos 4 períodos analisados, encontrando dificuldade em realizar o ajuste para a umidade relativa do ar no período chuvoso, tendo como a presença da água um possível causador dessa dificuldade. Para os dados de microclima do município de Cuiabá-MT, os resultados estão de acordo com as normais climatológicas e outros estudos realizados na mesma região.Palavras-chave: Semivariograma. Temperatura do Ar. Umidade Relativa do Ar. Precipitação.AbstractUrban parks serve as leisure areas and exercise practices, leading to concern about the thermal comfort of its users. Mãe Bonifácia Park, object of this study, is in the city of Cuiabá-MT, being a fragment of urban cerrado, suffering with all the seasonality of the local climate, having periods of strict drought and periods with precipitation. Thus the objective of this work was to make an analysis of the space-seasonalthermohygrometric variation through the kriging method of the aforementioned park. Monthly measurements of air temperature and relative humidity were taken at times between 10 and 12 hours. In the dry period the averages of the air temperature were 33.44oC, whereas the average temperature for the rainy period was 31,09oC. The mean relative humidity of the dry period was 43.34% and for the rainy season 68.71%. As a result the influence of the surroundings in the park was observed, being the lowest air temperatures and the hightest relative humidity of the air occurring in the central region of the park. The adjustments of the semivariograms were considered satisfactory for 3 of the 4 analyzed periods, finding it difficult to adjust for the relative humidity of the rainy season, with the presence of water being a possible cause of this difficulty. For the microclimate data of the municipality of Cuiabá-MT, the results are in agreement with the climate normals and other studies carried out in the same region.Keyword: Semivariogram. Air Temperature. Relative Humidity. Precipitation.

scholarly journals LOCAL MANIFESTATIONS OF CLIMATE CHANGES ON THE EXAMPLE OF “MEDOBORY” NATURE RESERVE DURING 2006-2020

2021 ◽  
Vol 51 (2) ◽  
pp. 64-73
Author(s):  
Iryna Bugalska
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Nature Reserve ◽  
Average Length ◽  
Dust Storms ◽  
Herbaceous Plant ◽  
Natural Phenomena ◽  
Entire Observation Period ◽  
Air Temperatures ◽  
Observation Period

The analysis of the main meteorological indicators, given according to the data of hydrometeorological post  in the village of Hrymailiv for the last fifteen years, is presented. The dynamics of changes in the average annual, monthly and daily, minimum, maximum air temperatures, precipitation, relative humidity, atmospheric pressure, etc. has been studied for the Nature Reserve "Medobory", the analysis of climatic features of months for the period of 2006-2020 is carried out. The temperature mode of the Reserve during the year is marked by considerable fluctuations of temperatures: from + 18,9ºС in July to -4,7ºС in January. The established duration of seasons is marked by strong variability, which is a sign of climate changing: the shortest and latest winter in the period of investigation recorded in 2016, began on December 29 and lasted 42 days, and the longest one - in 2018, lasted 130 days; the longest spring was in 2020 - 116 days, the shortest one - in 2018, lasted 30 days. The longest summer in 2018 lasted 147 days; in 2017-2018 a significant decrease in average daily air temperatures in the first half of July was observed; August and September parts of summer in 2016-2020 were hot, with fairly high maximums and very little precipitation. The latest beginning of autumn for the entire observation period is September 27, 2020, the shortest season - in 2016, only 53 days. The duration of autumn decreases, the average value reaches 75 days, the duration of summer increases - 112 days. It is noted that the nature of precipitation has changed - rain falls in the form of heavy, short-term showers, for one downpour the monthly norm of precipitations can fall out; over the last five years, the average length of the growing season has increased by 19 days and 13 days more than the average for fifteen years,  the sum of active temperatures above the average for the last five years by 299.3ºC, for the last fifteen years - by 183.5ºС. On the territory of the Nature Reserve "Medobory" other local manifestations of climate changing were recorded, expressed as follows: the average annual air temperature over the past five years increased by 0.5 ° C (the warmest for the entire observation period was 2020 with an average temperature of 10, 1ºС, just then there were 43 days in winter (61%) with positive daily average air temperatures); meteorological natural phenomena of nature became more frequent: heavy rains, snowfalls, heavy hail showers, ice, fogs, dust storms, ice frosting-up; exceeded the maximum air temperature for the last five years: October 3, 2016 (27.0 ° C), August 3, 2017 (38.5 ° C), May 25, 2018 (34.0 ° C), 21 June 2018 (34.0ºC), March 31, 2019 (21.2ºC), and the minimum - June 8, 2016 (0.0°C), July 7, 2017 (4.7°C), September 30, 2018 (-2.5°C), April 1, 2020 (-7.0°C). The latest spring light frost recorded on May 22, 2020 (-1.0ºC), which led to mass frosting-up of herbaceous plant species. Every autumn at the end of September, light frosts are already registered: -1.5ºC - September 28, 2016, -1.0ºC and -0.9ºC - September 29 and  September 30, 2017, -2.5ºC - September 30, 2018, - 1.8ºС - September 21, 2019, -1.0ºС - September 19, 2020, the last one - the earliest during the observation period and also in the summer part of September. For the first time in 2020, the relative humidity in March was 16% below normal, mainly due to the second and third decades (58% and 47% correspondingly), in April it was only 39% - 27% below normal. Such deviations were not observed even in the dry summer and autumn months. Key words: air temperature, precipitation, climatic seasons, meteorological natural phenomena.

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