scholarly journals Influence of Surface Reflection (Albedo) in Simulating the Sun Drying of Paddy Rice

2020 ◽  
Vol 10 (15) ◽  
pp. 5092
Author(s):  
Ana Salvatierra-Rojas ◽  
Victor Torres-Toledo ◽  
Joachim Müller

The sun drying of agricultural products is a complicated process involving heat transfer, mass transfer, and variable weather conditions. Surface reflection (albedo), a crop’s radiative property, plays an essential role in energy balance, and understanding its contribution can improve the thermal analysis. In this study, field experiments were conducted in the Philippines to explore the influence of surface albedo on the sun drying of paddy rice. First, we implemented energy and mass balance equations in a transient model with the surroundings using a graphical programming language in Matlab/Simulink®. Second, we identified the influence of albedo on the sun drying model by using a sensitivity analysis. Third, we investigated the relationship of paddy rice albedo and the solar zenith angle. Lastly, we integrated the albedo function into the sun drying model. The simulation outputs were validated with field experiments. A better estimation of the measured exit temperature and instantaneous mass were obtained when a variable albedo was applied. This study makes clear that introducing a variable albedo has a positive impact on model improvement. This information is important for application in solar drying technologies, so that the drying process can be better assessed.

2021 ◽  
Vol 64 (3) ◽  
pp. 1083-1094
Author(s):  
Diana M. Ramirez-Gutierrez ◽  
Klein E. Ileleji ◽  
Amanda J. Deering

HighlightsThe Page model best predicted the drying rates of mint leaves in thin-layer laboratory experiments under cyclical temperature change and in field experiments using open-air sun drying and Dehytray and Dehymeleon solar dryers.The total time for drying mint leaves with all solar drying methods was the same (48 h).For all drying methods, the aerobic bacterial count was significantly less on dried mint leaves than on fresh leaves.Color change was less impacted by sunlight with the Dehymeleon than with the Dehytray and open-air sun drying.Abstract. The drying kinetics and quality attributes of mint leaves (Mentha spitaca) were studied to determine the drying performance of two solar drying technologies (Dehymeleon V.2 and Dehytray) and their effect on dried mint quality. Field drying experiments were carried out under weather conditions at Purdue University, West Lafayette, Indiana. Thin-layer laboratory drying experiments were conducted for whole mint leaves at three temperatures [24°C (75°F), 35°C (95°F), and 54°C (130°F)] and airflow velocity of 1 m s-1 to determine the drying kinetics for the diurnal cycles typical for solar drying. The Page model was the most suitable model to predict the drying behavior of mint leaves for both the lab and field experiments. Even though the drying rate was higher with open-air sun drying on uncovered Dehytrays than with covered Dehytrays and the Dehymeleon, the total drying time for all methods was the same (48 h). Color change in mint leaves was less impacted by sunlight for mint leaves dried using the Dehymeleon, while the Dehytray and open-air sun drying had similar results due to their exposure to direct sunlight. For all drying methods, the aerobic bacterial count was significantly less for dried mint leaves than for fresh mint leaves. The log reductions in aerobic bacterial count achieved with open-air sun drying, Dehymeleon, and Dehytray were 0.47, 2.3, and 0.40, respectively. Keywords: Diffusion, Drying kinetics, Food quality, Mint leaves, Solar drying, Sun drying, Thin-layer drying.


2020 ◽  
Vol 80 (2) ◽  
pp. 133-146
Author(s):  
L Zhang ◽  
Z Zhang ◽  
J Cao ◽  
Y Luo ◽  
Z Li

Grain maize production exceeds the demand for grain maize in China. Methods for harvesting good-quality silage maize urgently need a theoretical basis and reference data in order to ensure its benefits to farmers. However, research on silage maize is limited, and very few studies have focused on its energetic value and quality. Here, we calibrated the CERES-Maize model for 24 cultivars with 93 field experiments and then performed a long-term (1980-2017) simulation to optimize genotype-environment-management (G-E-M) interactions in the 4 main agroecological zones across China. We found that CERES-Maize could reproduce the growth and development of maize well under various management and weather conditions with a phenology bias of <5 d and biomass relative root mean square error values of <5%. The simulated results showed that sowing long-growth-cycle cultivars approximately 10 d in advance could yield good-quality silage. The optimal sowing dates (from late May to July) and harvest dates (from early October to mid-November) gradually became later from north to south. A high-energy yield was expected when sowing at an early date and/or with late-maturing cultivars. We found that Northeast China and the North China Plain were potential silage maize growing areas, although these areas experienced a medium or even high frost risk. Southwestern maize experienced a low risk level, but the low soil fertility limited the attainable yield. The results of this paper provide information for designing an optimal G×E×M strategy to ensure silage maize production in the Chinese Maize Belt.


2018 ◽  
Vol 1 (94) ◽  
pp. 38-44
Author(s):  
А.M. Malienkо ◽  
N.E. Borуs ◽  
N.G. Buslaeva

In the article, the results of research on the methodology for conducting studies with corn culture under various methods of sowing and weather conditions. The aim of the research was to establish and evaluate the reliability and high accuracy of the experiment, with a decrease in the area's acreage and taking one plant per repetition. Based on the results of the analysis of biometric parameters and yields, the possibility of sampling from 5 to 108 plants was established statistically and mathematically to establish the accuracy of the experiment. The established parameters of sites in experiments with maize indicate the possibility of obtaining much more information from a smaller unit of area, that is, to increase labor productivity not only with tilled crops. This is the goal of further scientific research with other field crops taking 1 plant of repetitions, observing the conditions of leveling the experimental plot according to the fertility of the soil and sowing seeds with high condition. The data obtained give grounds for continuing research on the minimum space required and the sample in the experiments.


2019 ◽  
Vol 100 (4) ◽  
pp. 605-619 ◽  
Author(s):  
A. J. Illingworth ◽  
D. Cimini ◽  
A. Haefele ◽  
M. Haeffelin ◽  
M. Hervo ◽  
...  

Abstract To realize the promise of improved predictions of hazardous weather such as flash floods, wind storms, fog, and poor air quality from high-resolution mesoscale models, the forecast models must be initialized with an accurate representation of the current state of the atmosphere, but the lowest few kilometers are hardly accessible by satellite, especially in dynamically active conditions. We report on recent European developments in the exploitation of existing ground-based profiling instruments so that they are networked and able to send data in real time to forecast centers. The three classes of instruments are i) automatic lidars and ceilometers providing backscatter profiles of clouds, aerosols, dust, fog, and volcanic ash, the last two being especially important for air traffic control; ii) Doppler wind lidars deriving profiles of wind, turbulence, wind shear, wind gusts, and low-level jets; and iii) microwave radiometers estimating profiles of temperature and humidity in nearly all weather conditions. The project includes collaboration from 22 European countries and 15 European national weather services, which involves the implementation of common operating procedures, instrument calibrations, data formats, and retrieval algorithms. Currently, data from 265 ceilometers in 19 countries are being distributed in near–real time to national weather forecast centers; this should soon rise to many hundreds. One wind lidar is currently delivering real time data rising to 5 by the end of 2019, and the plan is to incorporate radiometers in 2020. Initial data assimilation tests indicate a positive impact of the new data.


2018 ◽  
Vol 4 (1) ◽  
pp. 65-70
Author(s):  
Jockie Zudhy Fibrianto ◽  
Mochamad Hilmy

The road corridor in Pontianak City has different shading output depending on the sun orientation. The difference has caused a temperature difference that affects the pedestrian thermal comfort along the corridor. Identification and measurement of shading temperatures that occur due to buildings and trees were carried out for three days in each afternoon with relatively similar weather conditions. The road corridor that becomes the research location was at A. Yani St.-Gajah Mada St.-Tanjung Pura St., which has a North-South orientation and Teuku Umar St.-Diponegoro St.-Sisingamangaraja St., who has an East-West direction. The analysis phase is done by comparing the effectiveness of imagery produced by buildings and trees. After that, the identification and measurement results are compared with Indonesian thermal comfort standards SNI T-14-1993-03 to obtain suitable thermal comfort in the road corridors in Pontianak City.


2021 ◽  
Vol 210 (07) ◽  
pp. 55-65
Author(s):  
Larisa Ikoeva ◽  
Oksana Haeva

Abstract. The purpose of the work is to study the influence of the growth regulator “Regoplant” and microfertilizer “Ultramag Kombi” on the photosynthetic productivity of the potatoes of the Barna variety based on the results of field experiments in the forest-steppe zone Republic of North Ossetia-Alania. Methods. Studies on the tasks were carried out in 2018–2020. at the experimental site of the NCRIMFA branch of the VSC of RAS in the conditions of the forest-steppe zone Republic of North Ossetia-Alania according to generally accepted methods. The soil of the experimental plot is medium-power heavy loamy leached chernozem, lined with pebbles. Results. It is established, that biological products under identical soil and weather conditions assisted different progress of plants and approach of phases of vegetation. For all variants of the experiment, the number of stems increased by 0,3–0,7 pcs., the height of the stems of potato plants – by 3,8–4,9 cm in comparison with the control. An intense increase in the mass of tops occurred when using a tank mixture (growth regulator “Regoplant” (25 ml/ha) + microfertilizer “Ultramag Combi” (0,75 l/ha)) – by 74 g/bush, or 15.5 % compared with the control variant. During the growing season, the sum of the photosynthetic potential (FP) was 1,070 thousand m2 •days/ha in the control, and on average 1198–1406 thousand m2•days/ha in the experimental variants. The greatest accumulation of dry matter was noted when using a tank mixture – 917 g/m2. The maximum pure photosynthetic productivity was observed in experimental variant IV – 6,52 g/m2•day compared to the control option. Scientific novelty. For the first time in the forest-steppe zone Republic of North Ossetia-Alania the effect of the growth regulator “Regoplant” and microfertilizer “Ultramag Kombi” on photosynthetic activity of potatoes was studied. Practical significance. The studies carried out make it possible to recommend in potato production the use of a tank mixture of an effective growth regulator “Regoplant” at a dose of 25 ml/ha and microfertilizer “Ultramag Combi” at a dose of 0,75 l/ha, as an ecologically safe and low-cost agricultural method when processing vegetative plants, providing an increase in yield and quality of tubers.


2021 ◽  
Author(s):  
Jaynie Vonk

This evaluation is presented as part of the Effectiveness Review Series 2018/19 on women’s empowerment. The BASIC START (Building Autonomous and Stable Institutions and Communities through Socially Cohesive, Transparent, Accountable and Responsive Transition) in the Bangsamoro' project was carried out in the Autonomous Region in Muslim Mindanao (ARMM) in the Philippines between April 2015 and August 2017, by Oxfam together with four implementing partners: Al Mujadilah Development Foundation (AMDF), United Youth of the Philippines Women (UnYPhil-Women), Tarbilang Foundation, and Women Engaged in Action on 1325 (WE Act 1325). The project aimed to promote women's empowerment and peacebuilding in the region. A quasi-experimental approach was used to assess the impact of the project activities in strengthening women’s empowerment. The evaluation used Oxfam's Women's Empowerment (WE) index. Overall, the evaluation found that the BASIC START project had a positive impact on Women's Empowerment in all three levels investigated – personal, relational and environmental. Find out more by reading the evaluation brief or the full report.


2021 ◽  
Author(s):  
Jacobo Varela Rodriguez ◽  
Sacha A. Brun ◽  
Antoine Strugarek ◽  
Victor Réville ◽  
Filippo Pantellini ◽  
...  

&lt;p&gt;&lt;span&gt;The aim of the study is to analyze the response of the Earth magnetosphere for various space weather conditions and model the effect of interplanetary coronal mass ejections. The magnetopause stand off distance, open-closed field lines boundary and plasma flows towards the planet surface are investigated. We use the MHD code PLUTO in spherical coordinates to perform a parametric study regarding the dynamic pressure and temperature of the solar wind as well as the interplanetary magnetic field intensity and orientation. The range of the parameters analyzed extends from regular to extreme space weather conditions consistent with coronal mass ejections at the Earth orbit. The direct precipitation of the solar wind on the Earth day side at equatorial latitudes is extremely unlikely even during super coronal mass ejections. For example, the SW precipitation towards the Earth surface for a IMF purely oriented in the Southward direction requires a IMF intensity around 1000 nT and the SW dynamic pressure above 350 nPa, space weather conditions well above super-ICMEs. The analysis is extended to previous stages of the solar evolution considering the rotation tracks from Carolan (2019). The simulations performed indicate an efficient shielding of the Earth surface 1100 Myr after the Sun enters in the main sequence. On the other hand, for early evolution phases along the Sun main sequence once the Sun rotation rate was at least 5 times faster (&lt; 440 Myr), the Earth surface was directly exposed to the solar wind during coronal mass ejections (assuming today&amp;#180;s Earth magnetic field). Regarding the satellites orbiting the Earth, Southward and Ecliptic IMF orientations are particularly adverse for Geosynchronous satellites, partially exposed to the SW if the SW dynamic pressure is 8-14 nPa and the IMF intensity 10 nT. On the other hand, Medium orbit satellites at 20000 km are directly exposed to the SW during Common ICME if the IMF orientation is Southward and during Strong ICME if the IMF orientation is Earth-Sun or Ecliptic. The same way, Medium orbit satellites at 10000 km are directly exposed to the SW if a Super ICME with Southward IMF orientation impacts the Earth.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;This work was supported by the project 2019-T1/AMB-13648 founded by the Comunidad de Madrid, grants ERC WholeSun, Exoplanets A and PNP. We extend our thanks to CNES for Solar Orbiter, PLATO and Meteo Space science support and to INSU/PNST for their financial support.&lt;/p&gt;


2021 ◽  
Vol 65 (10) ◽  
pp. 91-102
Author(s):  
N. Rogozhina

The choice of the countries of Southeast Asia as an example for analyzing the nature of interaction between developing countries and China within the framework of the Belt and Road Initiative is not accidental. The very logic of China’s stated goals of gaining dominant positions in the world economy and politics makes it inevitable that the countries of Southeast Asia located in geographic proximity to it are included in its long-term economic and political plans. The question, however, is to what extent do they meet the interests of the Southeast Asian countries themselves? The solution to this question is the main subject of research in the article. There are objective prerequisites for mutually beneficial cooperation. The Belt and Road projects are viewed by China as a tool for economic expansion into the region with the prospect of taking a leading position there, using the interest of Southeast Asian countries in the inflow of foreign investment to create modern infrastructure, the lack of which narrows their opportunities for further economic growth, maintaining competitiveness and developing integration ties within ASEAN Community. Expert assessments made by international organizations confirm the positive impact of OBOR projects on the economic development of Southeast Asian countries and although today it is too early to draw any conclusions, since the initiative is only at the initial stage of its implementation in the region, nevertheless the case studies presented in the article indicate a mismatch in the positions of the parties on a number of issues related to the financing of projects, their lack of transparency. non-compliance with environmental and social requirements. The support of the initiative on the part of the Southeast Asian countries does not automatically mean their acceptance of the terms of the agreements proposed by China, which are far from always consistent with their national interests and give rise to fears in society about its expansionist intentions. Therefore, in many Southeast Asian countries, participation in OBOR projects is turning into a subject of political discourse, which reflects the presence of disagreements in society and confrontation of interests regarding the advisability of rapprochement with China, given the associated economic and political risks. The countries of Southeast Asia can be conditionally divided into two groups according to their relation to the Belt and Road initiative. The first group includes Indonesia, Malaysia, Singapore, the Philippines, Thailand, Vietnam and Myanmar, whose position can be described as national pragmatism. While supporting the Chinese initiative in general, they nevertheless assess the possible risks of their participation in projects and seek to reduce them. The second group is represented by Laos and Cambodia, whose leadership unconditionally supports the Chinese initiative, guided by the interests of their own survival, which largely depends on Chinese assistance. Therefore, the prospect of falling into a debt trap and increasing economic dependence on the PRC and even the threat of losing sovereignty does not deter them from participating in highly controversial projects from a commercial point of view. Based on the analysis made, the author comes to the conclusion that, given the existing alignment of political forces in Southeast Asia, China can count on promoting its initiative in the region, which, however, does not automatically lead to an increase in its political influence and to the creation of a China-centric model of regional order. Acknowledgements. The article was prepared within the project “Post-crisis world order: challenges and technologies, competition and cooperation” supported by the grant from Ministry of Science and Higher Education of the Russian Federation program for research projects in priority areas of scientific and technological development (agreement № 075-15-2020-783).


2020 ◽  
Vol 12 (17) ◽  
pp. 6833
Author(s):  
Piotr Szulc ◽  
Katarzyna Ambroży-Deręgowska ◽  
Iwona Mejza ◽  
Joanna Kobus-Cisowska ◽  
Marta Ligaj

The subject of the work was the evaluation of maize protein yield conditioned by various agrotechnical factors. The test results are derived from two different field experiments covering a total of seven years of observation. Protein yield was significantly dependent on changing weather conditions in the growing seasons. Protein yield was significantly lower in the dry and hot years. The sum of precipitation for the month of May was positively correlated with maize protein yield. However, there was no correlation between the average air temperature and the amount of protein yield. The sum of atmospheric precipitation for the entire growing season (IV–X) shaped maize protein yield in over 96%. A non-linear relationship of the 2nd degree was determined between these traits. Sowing maize into the soil cultivated traditionally (autumn tillage), “stay-green” type cultivars and row fertilization positively influenced maize protein yield. Initial fertilization (regardless of depth) with two-component NP fertilizer, in relation to broadcast fertilization, significantly increased maize protein yield from 11.4% to 18%, respectively. The type of nitrogen fertilizer did not differentiate the value of this trait. Pre-sowing nitrogen application was more effective compared to the top dressing, and significantly increased protein yield. Row fertilization with two-component NP fertilizer clearly affected the content protein in grain. The interdependence of genetic and agronomic progress is an important factor shaping the potential of maize protein yield and cannot be attributed to either breeding (cultivar) or agronomy.


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