scholarly journals Study On Photovoltaic Modules On Greenhouse Roof For Energy And Strawberry Production

2019 ◽  
Vol 118 ◽  
pp. 03049
Author(s):  
Yilian Tang ◽  
Ming Li ◽  
Xun Ma
Keyword(s):  
Power Generation ◽  
Relative Humidity ◽  
The Other ◽  
Soluble Solids ◽  
Active Radiation ◽  
Photovoltaic Modules ◽  
Pv Modules ◽  
Roof Area ◽  
Microclimate Conditions ◽  
Better Than

The aim of this study was to investigate the effect of PV modules mounted on top of a greenhouse, on the growth of strawberries and microclimate conditions as well as to estimate the generated energy. In this study, two greenhouses with the same volume were established. One greenhouse was equipped with the opaque photovoltaic (OPV) modules which accounted for 25.9% of the roof area, and the other was equipped with the semi-transparent photovoltaic (STPV) modules which accounted for 20% of the roof area. The maximum annual power generation of OPV and STPV modules was 880 and 388 kWh with 30° tilt angle, respectively, by simulating different tilt angles. The temperature under the OPV and STPV modules was 2.9 and 1.1 °C lower than the unshaded part in the greenhouses, respectively, at noon in clear weather, and had little effect on relative humidity. The photosynthetically active radiation (PAR) under OPV and STPV modules was reduced by 43.5% and 31.7%, respectively, under the PE film greenhouse. The contents of soluble solids in strawberries in OPV and STPV greenhouses were 16.4 and 15.7 mg/g respectively, which were higher than those in unshaded samples. The quality and yield of the strawberry samples under the shade of OPV were better than those of the STPV shade.

scholarly journals Performance evaluation of polycrystalline photovoltaic modules in a Guinea Savanna and Mangrove swamp

2021 ◽  
Vol 4 (1) ◽  
pp. 011-021
Author(s):  
Nsed Ayip Akonjom ◽  
John Iyang Umuji ◽  
Ukoette Jeremiah Ekah
Keyword(s):  
Relative Humidity ◽  
Solar Power ◽  
Solar Flux ◽  
Mangrove Swamp ◽  
Cross River State ◽  
Photovoltaic Modules ◽  
Power Meter ◽  
Guinea Savanna ◽  
Pv Module ◽  
Pv Modules

This central idea of this research is to investigate how voltage, current, power output and efficiency of polycrystalline photovoltaic (PV) modules installed in a Guinea Savanna and Mangrove Swamp is affected by temperature, relative humidity and irradiance. The study locations are Calabar (mangrove swamp) and Ogoja (guinea savanna), in Cross River State, Nigeria. Two polycrystalline PV modules of exact specification mounted on a platform one-metre-high above the ground were used. A digital solar power meter (SM206) and a digital solar flux meter (MS 6616) was used to monitor and measure solar power and solar flux reaching the PV modules. A digital hygrometer and thermometer (KT-908) were used to monitor and measure the relative humidity and ambient temperature level at the height of installation and a digital multimeter (M880C+) accompanied with a temperature sensor was used to monitor voltage, current and panel temperature values from the modules. Analysis of the collected data reveals that the efficiency of the modules were not constant throughout the day. However, a higher voltage production and efficiency level was obtained for the PV module installed in Ogoja than that installed in Calabar under their respective levels of relative humidity, temperature and irradiance.

scholarly journals Electric Ferry Ecosystem for Sustainable Inter-Island Transport in Philippines: A Pilot Study

2018 ◽  
Vol 8 (6) ◽  
pp. 3570-3575
Author(s):  
E. V. Palconit ◽  
M. L. S. Abundo
Keyword(s):  
Energy Consumption ◽  
Pilot Study ◽  
Energy Management ◽  
Electric Propulsion ◽  
The Other ◽  
Energy Management System ◽  
Photovoltaic Modules ◽  
Pv Module ◽  
First Case ◽  
Pv Modules

An electric boat system as a pilot study for the electric ferry was designed and field-tested in Samal Island, Philippines, to verify sustainability for inter-island transport. This pilot study uses 4.5m monohull with a displacement weight of 343kg. During the experiment, two cases were compared: in the first case the boat was powered solely with batteries and in the other case with the aid of photovoltaic (PV) modules. For the first case, 24V electric propulsion was driven by two 12V, 100Ah batteries, which resulted to a navigational range of around 18, 16 and 15 trips with energy consumption of 111.64Wh, 117.19Wh and 123.92Wh respectively. In the second case, the photovoltaic modules were attached on the boat to supplement the PV used while on sail. Results in the second case showed that PV module supplemented energy was about to 13.4%, 26.8% and 38.7% using three different speeds like 3.18, 3.32 and 3.84knots and the navigational range extended to 4km, 1km, and 14.4km respectively. Therefore, the electric boat with the aid of PV module answers the problem in the energy management system that deals with the sustainability of the system in the inter-island transport in Philippines.

scholarly journals Shadow dispersion of PV Array under variable irradiance for superior power Generation by Magic Square Configuration

2018 ◽  
Vol 7 (1.8) ◽  
pp. 172 ◽  
Author(s):  
G Sreenivasa Reddy ◽  
T Bramhananda Reddy ◽  
M Vijaya Kumar
Keyword(s):  
Power Generation ◽  
Power Loss ◽  
Electrical Power ◽  
Partial Shading ◽  
Magic Square ◽  
Photovoltaic Modules ◽  
Pv Array ◽  
Pv Modules ◽  
Square Configuration ◽  
Comparison Data

The PV array generates smaller amount of the power compared with other electrical power generation components. There are many components that are adversely effected the output of PV array in such components, one is partial shading. Due to this, each module in PV array receives different solar irradiations causes different P-V characteristics of its peak values. This paper presents a pioneering method called as Magic Square configuration has been proposed to enhance the generated power of photovoltaic modules by configuring those are under affect of shade. Thus there is no change of electrical arrangement of PV modules in an array but only the objective location in the total cross tied (TCT) array is rearranged according to the magic square arrangement. Proposed paper gives comparison data with the conventional configuration method and hence the performance is calculated. The proposed technique provides a better solution that how shadow effect on the PV  modules has been reduced and how this shadow is distributed, and not only that also gives an idea  about how the inequality losses due to the partial shading is effectively reduced. The power loss of  various configurations of 3X3 and 4X4 array has been compared. The proposed technique is validated through MATLAB/Simulink environment. 

scholarly journals Shading by Overhang PV Collectors

2019 ◽  
Vol 9 (20) ◽  
pp. 4280
Author(s):  
Joseph Appelbaum ◽  
Avi Aronescu ◽  
Tamir Maor
Keyword(s):  
Incident Energy ◽  
Diffuse Radiation ◽  
Electrical Energy ◽  
The Other ◽  
Rear Side ◽  
Inclined Plate ◽  
Energy Beam ◽  
Photovoltaic Modules ◽  
Pv Module ◽  
Pv Modules

Photovoltaic modules integrated into buildings may provide shading to windows, doors and walls to protect against sun rays and at the same time generate ancillary electrical energy. The study develops the methodology for calculating the shadow variation cast by overhangs on doors, windows, carports, and calculates the annual incident energy (beam, diffuse and global energy) on overhangs made up of conventional and bifacial PV modules. The methodology of the present study is different from published articles including software programs. The study starts with shadows on walls cast by a horizontal pole and follows by shadows on walls cast by horizontal plates, inclined pole, inclined plate, and shaded area. The study deals also with overhangs placed one above the other. The calculation of the diffuse radiation involves the calculation of view factors to sky, to ground and between overhangs. In addition, the present study suggests using bifacial PV modules for overhangs and calculates the contribution of the reflective energy (5% and more) from walls and ground to the rear side of the bifacial PV module.

scholarly journals A New Index Assessing the Viability of PAR Application Projects Used to Validate PAR Models

Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 470
Author(s):  
Francisco Ferrera-Cobos ◽  
Jose M. Vindel ◽  
Rita X. Valenzuela
Keyword(s):  
Neural Networks ◽  
Artificial Neural Networks ◽  
Relative Humidity ◽  
Air Temperature ◽  
Satellite Data ◽  
Solar Zenith Angle ◽  
The Other ◽  
Clearness Index ◽  
Active Radiation ◽  
Climatic Regions

Photosynthetically active radiation (PAR) is a useful variable to estimate the growth of biomass or microalgae. However, it is not always feasible to access PAR measurements; in this work, two sets of nine hourly PAR models were developed. These models were estimated for mainland Spain from satellite data, using multilinear regressions and artificial neural networks. The variables utilized were combinations of global horizontal irradiance, clearness index, solar zenith angle cosine, relative humidity, and air temperature. The study territory was divided into regions with similar features regarding PAR through clustering of the PAR clearness index (kPAR). This methodology allowed PAR modeling for the two main climatic regions in mainland Spain (Oceanic and Mediterranean). MODIS 3 h data were employed to train the models, and PAR data registered in seven stations across Spain were used for validation. Usual validation indices assess the extent to which the models reproduce the observed data. However, none of those indices considers the exceedance probabilities, which allow the assessment of the viability of projects based on the data to be modeled. In this work, a new validation index based on these probabilities is presented. Hence, its use, along with the other indices, provides a double and thus more complete validation.

scholarly journals Storage of Habanero (D. rotundata) Yam

1969 ◽  
Vol 65 (1) ◽  
pp. 50-57
Author(s):  
Edelmiro J. Rodríguez ◽  
Orlando Parsi-Ros ◽  
Miguel A. González
Keyword(s):  
Relative Humidity ◽  
Sensory Evaluation ◽  
The Other ◽  
Ambient Conditions ◽  
Dioscorea Rotundata ◽  
Better Than

Yams (Dioscorea rotundata), variety Habanero, of three harvests gathered at 30-day intervals August, September and October were stored under ambient conditions (21° to 32°C and 60 to 90% relative humidity). The yams were sensory evaluated and weighed every 15 days. For sensory evaluation the yams were cut into two equal transversal portions, and in general, the bottom cuttings were found better than the top cuttings. Yams of the first harvest kept better in storage than those of the second and third harvests. All yams sprouted at about the same time. Around 50% of them sprouted between February and March, while around 90% had sprouted between March and April. All yams of the first harvest sprouted by the end of 7 1/2 months in storage while all of the second and third harvests had sprouted by the end of 6 months. Yams of the first harvest tended to lose less weight than those of the other two harvests.

Closing the GAP—A 5Å Scanning Microscope

1969 ◽  
Vol 27 ◽  
pp. 6-7
Author(s):  
A. V. Crewe
Keyword(s):  
Normal Form ◽  
The Other ◽  
Resolving Power ◽  
Scanning Microscope ◽  
Conventional Microscope ◽  
Other Hand ◽  
Closing The Gap ◽  
Thermal Sources ◽  
Better Than ◽  
Transmission Microscope

We have become accustomed to differentiating between the scanning microscope and the conventional transmission microscope according to the resolving power which the two instruments offer. The conventional microscope is capable of a point resolution of a few angstroms and line resolutions of periodic objects of about 1Å. On the other hand, the scanning microscope, in its normal form, is not ordinarily capable of a point resolution better than 100Å. Upon examining reasons for the 100Å limitation, it becomes clear that this is based more on tradition than reason, and in particular, it is a condition imposed upon the microscope by adherence to thermal sources of electrons.

MUNDANE MIRACLES IN AWADH. ENCOUNTERS WITH THE REVEALED AND THE HIDDEN

2020 ◽  
pp. 130-140
Author(s):  
Maxim B. Demchenko ◽  
Keyword(s):  
The Other ◽  
Local People ◽  
Natural Phenomena ◽  
Mughal Empire ◽  
The Public ◽  
British Raj ◽  
The Subject ◽  
Other World ◽  
Better Than

The sphere of the unknown, supernatural and miraculous is one of the most popular subjects for everyday discussions in Ayodhya – the last of the provinces of the Mughal Empire, which entered the British Raj in 1859, and in the distant past – the space of many legendary and mythological events. Mostly they concern encounters with inhabitants of the “other world” – spirits, ghosts, jinns as well as miraculous healings following magic rituals or meetings with the so-called saints of different religions (Hindu sadhus, Sufi dervishes),with incomprehensible and frightening natural phenomena. According to the author’s observations ideas of the unknown in Avadh are codified and structured in Avadh better than in other parts of India. Local people can clearly define if they witness a bhut or a jinn and whether the disease is caused by some witchcraft or other reasons. Perhaps that is due to the presence in the holy town of a persistent tradition of katha, the public presentation of plots from the Ramayana epic in both the narrative and poetic as well as performative forms. But are the events and phenomena in question a miracle for the Avadhvasis, residents of Ayodhya and its environs, or are they so commonplace that they do not surprise or fascinate? That exactly is the subject of the essay, written on the basis of materials collected by the author in Ayodhya during the period of 2010 – 2019. The author would like to express his appreciation to Mr. Alok Sharma (Faizabad) for his advice and cooperation.

Temperature Effects during Endodormancy Induction on Subsequent Anthesis and Growth of Peach Trees

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 452c-452 ◽  
Author(s):  
Schuyler D. Seeley ◽  
Raymundo Rojas-Martinez ◽  
James Frisby
Keyword(s):  
Temperature Effects ◽  
Shoot Length ◽  
The Other ◽  
Nighttime Temperatures ◽  
Peach Trees ◽  
Better Than

Mature peach trees in pots were treated with nighttime temperatures of –3, 6, 12, and 18 °C for 16 h and a daytime temperature of 20 °C for 8 h until the leaves abscised in the colder treatments. The trees were then chilled at 6 °C for 40 to 70 days. Trees were removed from chilling at 40, 50, 60, and 70 days and placed in a 20 °C greenhouse under increasing daylength, spring conditions. Anthesis was faster and shoot length increased with longer chilling treatments. Trees exposed to –3 °C pretreatment flowered and grew best with 40 days of chilling. However, they did not flower faster or grow better than the other treatments with longer chilling times. There was no difference in flowering or growth between the 6 and 12 °C pretreatments. The 18 °C pretreatment resulted in slower flowering and very little growth after 40 and 50 days of chilling, but growth was comparable to other treatments after 70 days of chilling.

Nglyc: A Random Forest Method for Prediction of N-Glycosylation Sites in Eukaryotic Protein Sequence

2020 ◽  
Vol 27 (3) ◽  
pp. 178-186 ◽  
Author(s):  
Ganesan Pugalenthi ◽  
Varadharaju Nithya ◽  
Kuo-Chen Chou ◽  
Govindaraju Archunan
Keyword(s):  
Random Forest ◽  
Protein Sequence ◽  
Glycosylation Site ◽  
Computational Method ◽  
The Other ◽  
Eukaryotic Protein ◽  
Random Forest Method ◽  
Glycosylation Sites ◽  
Human And Mouse ◽  
Better Than

Background: N-Glycosylation is one of the most important post-translational mechanisms in eukaryotes. N-glycosylation predominantly occurs in N-X-[S/T] sequon where X is any amino acid other than proline. However, not all N-X-[S/T] sequons in proteins are glycosylated. Therefore, accurate prediction of N-glycosylation sites is essential to understand Nglycosylation mechanism. Objective: In this article, our motivation is to develop a computational method to predict Nglycosylation sites in eukaryotic protein sequences. Methods: In this article, we report a random forest method, Nglyc, to predict N-glycosylation site from protein sequence, using 315 sequence features. The method was trained using a dataset of 600 N-glycosylation sites and 600 non-glycosylation sites and tested on the dataset containing 295 Nglycosylation sites and 253 non-glycosylation sites. Nglyc prediction was compared with NetNGlyc, EnsembleGly and GPP methods. Further, the performance of Nglyc was evaluated using human and mouse N-glycosylation sites. Results: Nglyc method achieved an overall training accuracy of 0.8033 with all 315 features. Performance comparison with NetNGlyc, EnsembleGly and GPP methods shows that Nglyc performs better than the other methods with high sensitivity and specificity rate. Conclusion: Our method achieved an overall accuracy of 0.8248 with 0.8305 sensitivity and 0.8182 specificity. Comparison study shows that our method performs better than the other methods. Applicability and success of our method was further evaluated using human and mouse N-glycosylation sites. Nglyc method is freely available at https://github.com/bioinformaticsML/ Ngly.

Sign in / Sign up

Export Citation Format

Share Document