Preferred Language
Articles
/
vBYJdIcBVTCNdQwCBkun
Improving Nitrogen Management in Potatoes with Active Optical Sensors
...Show More Authors

Nitrogen (N) fertilizer rate is important for high yield and good quality of potato tubers. In this dissertation, I seek to study the response of different potato cultivars under different N fertilizer rates and how that can impact tuber quality, examine the performance of active optical sensors in improving a potato yield prediction algorithm, and evaluate the ability of active optical sensors (GreenSeeker (GS) and Crop Circle (CC)) to optimize a N recommendation algorithm that can be used by potato growers in Maine. This research was conducted at 11 sites over a period of two years (2018–2019) in Aroostook County, Maine; all sites depended on a rainfed system. Three potato cultivars, Russet Burbank, Superior, and Shepody, were planted under six rates of N (0-280 kg ha-1), ammonium sulfate and ammonium nitrate, and were applied in a randomized complete block design (RCBD) with four replications. Active optical sensor readings (normalized difference vegetation index (NDVI)) were collected weekly after the fourth leaf stage began. The coefficient of determination (R2) between soil organic matter (OM) content and total tuber yield for all sites combined was 0.78**. Sites with ≥ 30 g kg-1 of soil OM produced higher total tuber yield, marketable yield, and tuber weight per plant (39.45%, 45.22%, and 54.94%, respectively) than sites with ≤ 30 g kg-1 of OM. Specific gravity increased by 0.18% in the sites with ≥ 30 g kg-1 of OM. The total tuber yield for the three cultivars was maximized at 168 kg N ha-1. Vegetation indices measurements obtained at stages of 16 or 20 fully expanded leaves were significantly correlated with tuber yield, which can be used in the yield prediction model. Sensor measurements obtained at the 20th leaf stage were significantly correlated with tuber yield, with the exponential model showing the best fit for the regression curve. The recommended N rate calculated based on in-season sensor readings was reduced by approximately 12–14% compared to the total N rate that growers currently apply based on the conventional approach.

View Publication
Publication Date
Sat Sep 21 2013
Journal Name
Nonlinear Dynamics
BER performance enhancement for secure wireless optical communication systems based on chaotic MIMO techniques
...Show More Authors

View Publication
Scopus (7)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Mon Apr 10 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of Thickness on Electrical Conductivity and Optical Constant of Fe2O3 Thin Films
...Show More Authors

   In this research the electrical conductivity and optical measurements were made on the Iron Oxide (Fe2O3) films prepared by chemical spray pyrolysis method as a function of thickness (250, 350, 450, and 550)  20 nm.    The measurements of electrical conductivity (σ), activation energies (Ea1, Ea2),and optical constant such as absorption coefficient, refractive index, extinction coefficient and the dielectric constants for the wavelengths in the range (300-900) nm have been investigated on (Fe2O3) thin films as a function of thickness. All films contain two types of transport mechanisms, and the electrical conductivity (σ) increases whereas the activation energy (Ea) would decrease as the films thi

... Show More
View Publication Preview PDF
Publication Date
Tue Apr 05 2022
Journal Name
Nano Hybrids And Composites
Structural and Optical Properties of ZnO Nanostructures Synthesized by Hydrothermal Method at Different Conditions
...Show More Authors

Zinc oxide (ZnO) nanoparticles were synthesized using a modified hydrothermal approach at different reaction temperatures and growth times. Moreover, a thorough morphological, structural and optical investigation was demonstrated using scanning electron microscopy (SEM), x-ray diffraction (XRD), ultra-violate visible light spectroscopy (UV-Vis.), and photoluminescence (PL) techniques. Notably, SEM analysis revealed the occurrence of nanorods-shaped surface morphology with a wide range of length and diameter. Meanwhile, a hexagonal crystal structure of the ZnO nanoparticles was perceived using XRD analysis and crystallite size ranging from 14.7 to 23.8 nm at 7 and 8 ℎ𝑟𝑠., respectively. The prepared ZnO samples showed good abso

... Show More
Publication Date
Mon May 22 2023
Journal Name
Proceedings Of The 1st International Conference On Frontier Of Digital Technology Towards A Sustainable Society
Effect of thermal annealing on the structural and optical properties of Sb2Se3 thin films
...Show More Authors

In this paper the effect of thermal annealing on the structural and optical properties of Antimony Selenide (Sb2Se3) is investigated. Sb2Se3 powder is evaporated on clean amorphous glass substrates at room temperature under high vacuum pressure (4.5×10-6 mbar) to form thin films. The structural investigation was done with the aid of X-ray diffraction (XRD) and atomic force microscopy (AFM). The amorphous to polycrystalline transformation of these thin films was shown by X-ray diffraction analysis after thermal annealing. These films' morphology is explained. (UV-Vis ) spectra in ranges from 300 to 1100 nm was used to examine the optical properties of the films .The absorption coefficient and optical energy gap of the investigated films are

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Fri Mar 01 2019
Journal Name
Iraqi Journal Of Physics
The effect of rear earth doping CdS nanostructure on structural, optical and photoconductivity properties
...Show More Authors

Rare earth elements (Cerium, Lanthanum and Neodymium) doped CdS thin films are prepared using the chemical Spray Pyrolysis Method with temperature 200 oC. The X-ray diffraction (XRD) analysis refers that pure CdS and CdS:Ce, CdS:La and CdS:Nd thin films showed the hexagonal crystalline phase. The crystallite size determined by the Debye-Scherrer equation and the range was (35.8– 23.76 nm), and it was confirmed by field emission scanning electron microscopy (FE-SEM). The pure and doped CdS shows a direct band gap (2.57 to 2.72 eV), which was obtained by transmittance. The room-temperature photoluminescence of pure and doped CdS shows large peak at 431 nm, and two small peaks at (530 and 610 nm). The Current – voltage measurement in da

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Oct 20 2022
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Evaluating the Optical Properties of the Schmidt Cassegrain Spider Obscuration Telescope Using Zemax Program
...Show More Authors

Schmidt Cassegrain spider obscuration telescope (SCT) is one of the types of observations operating with a concave mirror. It combines several lenses and mirrors working together as an optical system. The light rays fall into the tube from the main mirror and gather on another smaller mirror called a secondary mirror. Unlike the formation of Newton's telescope, no light is made from the secondary mirror out the side of the tube but is directed to the middle of the main mirror. There is an opening in the middle of the main mirror so the light beam can go out and direct the vision lens system. The secondary mirror is located in the middle of a glass slice and is installed by thin carriers. The function of this board is to correct the portr

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 03 2013
Journal Name
Baghdad Science Journal
Study the effects of bromothymol blue material on the optical properties for polystyrene (PS).
...Show More Authors

Films of pure polystyrene (ps) and doped by bromothymol blue material with percentages(4%) prepared by using casting technique in room temperature , the absorption and transmission spectra has been recorded in the wavelength rang (200-900)nm and calculated refractive index , reflectivity, real and imaginary parts of dielectric constant and extinction coefficient . this study has been done by recording the absorption and transmission spectra by using spectrophotometer .

View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Structural and Optical Properties of SnS2:Cu Thin films prepared by chemical Spbay Pyrolysis
...Show More Authors

Thin filis have been prepared from the tin disulphide (SnS2 ), the pure and the doped with copper (SnS2:Cu) with a percentages (1,2,3,4)% by using ahemical spray pyrolysis techniqee on substrate of glass heated up to(603K)and sith thicknesses (0.7±0.02)?m ,after that the films were treated thermally with a low pressure (10-3mb) and at a temperature of (473K) for one hour. The influence of both doping with copper and the thermal treatment on some of the physical characteristics of the prepared films(structural and optical) was studied. The X-ray analysis showed that the prepared films were polycrystalline Hexagonal type. The optical study that included the absorptance and transmitance spectra in the weavelength range (300-900)nm

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Jan 01 2014
Journal Name
Journal Of The College Of Basic Education
Effect of annealing temperature on Structural and Optical properties of amorphous Selenium thin films
...Show More Authors

Publication Date
Sat Oct 01 2011
Journal Name
Iraqi Journal Of Physics
The Role of Annealing Temperature on the Optical Properties of Thermally Deposited CdTe Films
...Show More Authors

A polycrystalline CdTe film has been prepared by thermal evaporation technique on glass substrate at substrate temperature 423 K with 1.0 m thicknesses. The film was heated at various annealing temperature under vacuum (Ta =473, 523 and K). Some of physical properties of prepared films such as structural and optical properties were investigated. The patterns of X-ray diffraction analysis showed that the structure of CdTe powder and all films were polycrystalline and consist of a mixture of cubic and hexagonal phases and preferred orientation at (111) direction.
The optical measurements showed that un annealed and annealed CdTe films had direct energy gap (Eg). The Eg increased with increasing Ta. The refractive index and the real p

... Show More
View Publication Preview PDF