scholarly journals «Lighting price» of cucumber yield in the winter-spring turnover of greenhouses

2021 ◽  
pp. 34-38
Author(s):  
A. V. Kurepin ◽  
A. F. Pershin ◽  
V. N. Shevkunov
Keyword(s):  
Solar Radiation ◽  
Light Energy ◽  
F1 Hybrids ◽  
Total Solar Radiation ◽  
Artificial Lighting ◽  
Crop Selection ◽  
Breeding Center ◽  
Testing Site ◽  
Cucumber Yield ◽  
Incoming Light

Relevance. Among the main factors that determine the productivity of vegetable yields in protected ground, the main one is light. For the formation of 1 kg/m2 of cucumber fruits with a length of 18-22 cm, on average about 3500-4000 J/cm2 of solar radiation is required. In the winter-spring cycle, in the absence of artificial lighting in greenhouses, there is an unevenness of scattered solar radiation and a general shortage of incoming light energy. At the same time, the amount of total solar radiation required for the formation of a 1 kg of fruit ("lighting price") is not the same for different hybrids. To increase the profitability of production in the winter-spring turnover in greenhouses that are not equipped with artificial lighting, it is necessary to choose hybrids with the lowest "lighting price" of the crop, that is, hybrids that use less light energy to form a 1 kg of fruit.The purpose of the study: evaluation of F1 hybrids of cucumber on the basis of resistance to lack of lighting by comparing their "lighting price" of the crop: how much energy is spent on the formation of 1 kg of marketable products.Methods. The research was carried out at the variety testing site in the Crimean breeding Center of the Scientific Research Institute of Vegetable Crop Selection "Gavrish", in the conditions of winter-spring turnover, in greenhouses not equipped with artificial lighting. We tested seven medium-fruited (18-22 cm) spined-fruited cucumber hybrids recommended for growing in winter-spring turnover.Results. The analysis of the data on the input of solar radiation and the formation of a standard yield showed that there is a direct relationship between the amount of incoming light and the level of productivity. The period of conversion of the received solar energy into the fruit harvest varied during the growing season from 14 to 8 days, depending on the degree of plant development. The "lighting price" of the crop was not the same for different hybrids: the hybrids tested in the experiment spent an average of 2900 J/cm2 per 1 kg of product, which is 18% more efficient than for standard greenhouse cucumbers. 

scholarly journals Trees as a solar control measure for southern-oriented street frontages. Analysis of a selected street model for a humid continental climate

2021 ◽  
Author(s):  
Katarzyna Zielonko-Jung ◽  
Justyna Janiak
Keyword(s):  
Numerical Simulation ◽  
Solar Radiation ◽  
Control Measure ◽  
Total Solar Radiation ◽  
Single Row ◽  
Ground Floor ◽  
Radical Reduction ◽  
Solar Control ◽  
Sycamore Maple ◽  
Continental Climate

AbstractThe present study is aimed at the analysis of possibilities for shading southern frontage of street oriented along the E-W axis by the single row of trees, parallel to the southern elevations. The effectiveness of solar control shading was tested depending on the geometric relationships between trees and buildings. Numerical simulation analyses were conducted in Rhinoceros® program for the street located in humid continental climate in city Płock, Poland (52°32′50 “N 19°42’00 “E), for the day of the highest degree of total solar radiation in the year i.e. June 7th, during hours: 8.00a.m - 5.00 p.m. The analysis has proved that a row of 20–25 year old Sycamore Maple ‘Rotterdam’ in the street 30 m wide and 18 m high (H/W = 0.6), can provide solar protection for the southern frontage, especially when trees are located no more than 4 m away. Location of greenery within the range of 4 to 5 m from the buildings leads to a radical reduction in the possibility of shading the wall surfaces (at 5 m to 0%). Over 90% of the shading area of the ground floor façade walls was found when trees were within the distance 2 and 3 m away from the building.

Estimation of the total solar radiation from meteorological data

Solar Energy ◽  
1977 ◽  
Vol 19 (3) ◽  
pp. 307-311 ◽  
Author(s):  
J.A. Sabbagh ◽  
A.A.M. Sayigh ◽  
E.M.A. El-Salam
Keyword(s):  
Solar Radiation ◽  
Meteorological Data ◽  
Total Solar Radiation

scholarly journals High resolution grid of potential incoming solar radiation for Serbia

2015 ◽  
Vol 19 (suppl. 2) ◽  
pp. 427-435 ◽  
Author(s):  
Jelena Lukovic ◽  
Branislav Bajat ◽  
Milan Kilibarda ◽  
Dejan Filipovic
Keyword(s):  
Solar Radiation ◽  
Driving Force ◽  
Total Solar Radiation ◽  
Surface Solar Radiation ◽  
Natural Processes ◽  
Web Map ◽  
Complex Interactions ◽  
The Earth ◽  
Digital Elevation ◽  
Elevation Model

Solar radiation is a key driving force for many natural processes. At the Earth?s surface solar radiation is the result of complex interactions between the atmosphere and Earth?s surface. Our study highlights the development and evaluation of a data base of potential solar radiation that is based on a digital elevation model (DEM) with a resolution of 90 m over Serbia. The main aim of this paper is to map solar radiation in Serbia using DEM. This is so far the finest resolution being applied and presented using DEM. The final results of the potential direct, diffuse and total solar radiation as well as duration of insolation databases of Serbia are portrayed as thematic maps that can be communicated and shared easily through the cartographic web map-based service.

scholarly journals STRUCTURE AND INTERANNUAL DYNAMICS OF THE REGIONAL ECOSYSTEMS RADIATION BALANCE OF THE PLAIN CRIMEA

Ekosistemy ◽  
2021 ◽  
pp. 5-15
Author(s):  
R. V. Gorbunov ◽  
T. Yu. Gorbunova ◽  
V. A. Tabunshchik ◽  
A. V., Drygval
Keyword(s):  
Solar Radiation ◽  
Short Wave ◽  
Radiation Balance ◽  
Total Solar Radiation ◽  
Western Coast ◽  
Climate Data ◽  
Crimean Peninsula ◽  
Wave Part ◽  
Interannual Dynamics ◽  
Landscape Level

The research team calculated the values of the radiation balance elements of the plain Crimea ecosystems on the bases of open databases of climate data and GIS-modeling and, moreover, analyzed their spatial and temporal differentiation. It is revealed that the spatial distribution of the radiation balance is characterized by an increase in values from the center to the coast of the peninsular. It correlates with the spatial differentiation of both total solar radiation and all other elements of the short-wave part of the radiation balance. There is a significant excess of radiation balance values of the plateau landscape level ecosystems over values of the hydromorphic landscape level ecosystems. This difference is determined by the location of selected key areas on the western coast of the Crimean Peninsula, which is characterized by the maximum values of total solar radiation supply. The elements of the long-wave part of the radiation balance change in the opposite direction, compared with the short-wave part of the radiation balance, which is associated with an increase of air temperature and climate continentality in the direction from the coast to the center of the peninsula. Two periods were identified in the interannual dynamics corresponding to the change of the circulatory periods of the Northern Hemisphere. In general, the considered ecosystems are characterized by trends of increasing radiation balance values in conditions of growth of all its elements. Such growth is provided by significant increase of values during the second period compared with the negative trends of radiation balance values for a number of ecosystems in the first one.

Maximisation and Optimisation of the Total Solar Radiation Reaching the Solar Collector Surfaces

2015 ◽  
pp. 873-886 ◽  
Author(s):  
Kacem Gairaa ◽  
Abdallah Khellaf ◽  
Farouk Chellali ◽  
Said Benkaciali ◽  
Yahia Bakelli ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Solar Collector ◽  
Total Solar Radiation

scholarly journals The effect of climatic and geographical factors on breast cancer in Iran

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Zohreh Maryanaji
Keyword(s):  
Breast Cancer ◽  
Environmental Factors ◽  
Solar Radiation ◽  
Total Solar Radiation ◽  
Electromagnetic Spectrum ◽  
Health It ◽  
Northern Latitudes ◽  
Low Latitudes ◽  
Low Altitude ◽  
Radiation Angle

Abstract Objective By studying the effect of environmental factors on health, it is clear that geographical, climatic and environmental factors have a significant impact on human health. This study, based on the data of the patients with breast cancer in Iran since 2010 to 2014 and using the statistical methods has determined the effect of geographical features of Iran (solar radiation status, radiation angle) on the frequency and distribution of this disease. Results The maximum amount of total solar radiation occurs in the vicinity (surrounding) of the tropic of cancer, which covers some parts of the south of Iran and in the atmosphere of the northern latitudes of Iran. The amount of humidity and cloudiness is more than the southern latitudes, which causes more reflection of short waves of the sun during the day. Findings showed that the rate of breast cancer in low latitudes is higher than high latitudes. It was also found that with increasing longitude, the rate of cancer increases significantly due to the high thickness of the atmosphere and receiving more sunlight in the electromagnetic spectrum, as well as dry air and low water vapor in low altitude areas of eastern and southeastern Iran.

scholarly journals Optimum Tilt Angle and Orientation of Photovoltaic Thermal System for Application in Greater Toronto Area, Canada

2019 ◽  
Vol 11 (22) ◽  
pp. 6443 ◽  
Author(s):  
Hailu ◽  
Fung
Keyword(s):  
Solar Radiation ◽  
Tilt Angle ◽  
Solar Panel ◽  
Solar Irradiation ◽  
Transfer Model ◽  
Total Solar Radiation ◽  
Outlet Temperature ◽  
Anisotropic Models ◽  
Greater Toronto Area ◽  
Steady State Heat Transfer

We present a study conducted to obtain optimum tilt angle and orientation of a solar panel for the collection of maximum solar irradiation. The optimum tilt angle and orientation were determined using isotropic and anisotropic diffuse sky radiation models (isotropic and anisotropic models). The four isotropic models giving varying optimum tilt angles in the range of 37 to 44°. On the other hand, results of the four anisotropic models were more consistent, with optimum tilt angles ranging between 46–47°. Both types of models indicated that the collector tilt should be changed four times a year to receive more solar radiation. The results also indicate that the solar panel should be installed with orientation west or east of due south with a flatter tilt angle. A 15° change in orientation west or east of due south results in less than 1% reduction of the total solar radiation received. For a given optimum tilt angle, the effect of photovoltaic/thermal (PV/T) orientation west or east of due south on the outlet temperature was determined using a one-dimensional steady state heat transfer model. It was found that there is less than 1.5% decrease in outlet temperature for a PV/T panel oriented up to 15° east or west of due south from March to December. This result indicates that existing roofs with orientations angles up to 15° east or west of due south can be retrofitted with a PV/T system without changing the roof shape.

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