Simple technique to improve the spectral quality of gain-switched pulses from a DFB laser

1994 ◽  
Vol 30 (25) ◽  
pp. 2143-2145 ◽  
Author(s):  
L.P. Barry ◽  
J. Debeau ◽  
R. Boittin
Keyword(s):  
Simple Technique ◽  
Spectral Quality ◽  
Dfb Laser

scholarly journals Integration of Satellite Data with High Resolution Ratio: Improvement of Spectral Quality with Preserving Spatial Details

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4418 ◽  
Author(s):  
Aleksandra Sekrecka ◽  
Michal Kedzierski
Keyword(s):  
High Ratio ◽  
Data Sets ◽  
Spectral Quality ◽  
Local Statistics ◽  
Panchromatic Image ◽  
Urbanized Area ◽  
Fusion Methods ◽  
Spatial Quality ◽  
Different Levels

Commonly used image fusion techniques generally produce good results for images obtained from the same sensor, with a standard ratio of spatial resolution (1:4). However, an atypical high ratio of resolution reduces the effectiveness of fusion methods resulting in a decrease in the spectral or spatial quality of the sharpened image. An important issue is the development of a method that allows for maintaining simultaneous high spatial and spectral quality. The authors propose to strengthen the pan-sharpening methods through prior modification of the panchromatic image. Local statistics of the differences between the original panchromatic image and the intensity of the multispectral image are used to detect spatial details. The Euler’s number and the distance of each pixel from the nearest pixel classified as a spatial detail determine the weight of the information collected from each integrated image. The research was carried out for several pan-sharpening methods and for data sets with different levels of spectral matching. The proposed solution allows for a greater improvement in the quality of spectral fusion, while being able to identify the same spatial details for most pan-sharpening methods and is mainly dedicated to Intensity-Hue-Saturation based methods for which the following improvements in spectral quality were achieved: about 30% for the urbanized area and about 15% for the non-urbanized area.

scholarly journals On the Spectral Quality of Time-Resolved CMOS SPAD-Based Raman Spectroscopy With High Fluorescence Backgrounds

2020 ◽  
Vol 20 (9) ◽  
pp. 4635-4645
Author(s):  
Jere Kekkonen ◽  
Tuomo Talala ◽  
Jan Nissinen ◽  
Ilkka Nissinen
Keyword(s):  
Raman Spectroscopy ◽  
Spectral Quality ◽  
Time Resolved ◽  
High Fluorescence

Harmonics control of three phase voltage source inverter with random carriers and modified reference

2021 ◽  
pp. 002072092199659
Author(s):  
R Anand ◽  
L Padmasuresh ◽  
P Muthukumar ◽  
P Sreeja ◽  
V Krishnakumar ◽  
...  
Keyword(s):  
Motor Drives ◽  
Voltage Source ◽  
Spectral Quality ◽  
Phase Voltage ◽  
Voltage Source Inverter ◽  
Middle Portion ◽  
Induction Motor Drives ◽  
Three Phase ◽  
Experimental Values

The Harmonics control of any inverters can be decided by the PWM incorporated for the switches. In recent years the carrier and reference modification based research is going on the inverter field. This paper suggests that the alteration of carriers and references of the three phase voltage source inverter enhance the ability to decrease the harmonic content.This enhanced realization deals with the carrier and reference modification arrangement for three phase voltage source inverter through amalgamating the boosted reference and random triangular carrier. The boosted reference is the addition of sine reference with injection of 1/3rd of reference amplitude (3fs) in the middle portion of the reference wave. i.e., [Formula: see text] to [Formula: see text] and [Formula: see text] to [Formula: see text] . The proposed PWM scheme use two carriers, one is Triangle wave and another one is inverted Triangle wave. The process of selecting the winning carrier among the two triangle carriers is purely based on the LFSR technique. The spectral quality of the induction motor drives has improved by the random carriers. The simulation and experimental values are proving the validity of the PWM method. The PWMs are generated by using parallel processing enabled FPGA processor.

Perception of shade

1983 ◽  
Vol 303 (1116) ◽  
pp. 503-521 ◽  
Keyword(s):  
Blue Light ◽  
Physiological Responses ◽  
Specific Form ◽  
Radiation Environment ◽  
Physiological Age ◽  
Fluence Rate ◽  
Spectral Quality ◽  
Natural Radiation ◽  
Environment Changes

Plants perceive shade by responding to both the fluence rate and to the spectral quality of the natural radiation environment. Changes in fluence rate are perceived by separate photoreceptors absorbing in both the blue and the red wavebands. The identity of the photoreceptor (or photoreceptors) responding to changes in the fluence rate of blue light is unknown (see Briggs, this volume). Physiological responses to changes in the fluence rate in the red waveband appear to be mediated through phytochrome. The relative roles played by the blue-light-absorbing photoreceptor and phytochrome in determining the response to changes in fluence rate varies between species and organs and is also dependent on the physiological age of the plant. Evidence is also presented that supports the concept that phytochrome functions to perceive the specific form of shade caused by surrounding competitive vegetation.

scholarly journals Spectral pre and post processing for infrared and Raman spectroscopy of biological tissues and cells

2016 ◽  
Vol 45 (7) ◽  
pp. 1865-1878 ◽  
Author(s):  
Hugh J. Byrne ◽  
Peter Knief ◽  
Mark E. Keating ◽  
Franck Bonnier
Keyword(s):  
Raman Spectroscopy ◽  
Spectral Data ◽  
Biomedical Applications ◽  
Biological Tissues ◽  
Spectral Quality ◽  
Post Processing ◽  
Factors Influencing ◽  
Infrared And Raman Spectroscopy ◽  
Processing Steps

This review presents the current understanding of the factors influencing the quality of spectra recorded and the pre-processing steps commonly employed to improve on spectral quality, as well as some of the most common techniques for classification and analysis of the spectral data for biomedical applications.

scholarly journals Drying and sortation to improve green beans and cup quality of Wamena coffee

2021 ◽  
Vol 306 ◽  
pp. 03024
Author(s):  
Adnan ◽  
Martina Sri Lestari
Keyword(s):  
Simple Technique ◽  
Descriptive Analysis ◽  
Quality Score ◽  
Local Culture ◽  
Green Coffee ◽  
Green Beans ◽  
Green Coffee Beans ◽  
Coffee Beans ◽  
Cup Quality

Drying and sortation are the most important steps to improve green coffee beans and cup quality. However, farmers very often neglect these steps. Therefore, a simple technique and soft approach are required to encourage farmers to implement drying and sortation technology. The study aim is to assess suitable drying and sortation technology to improve green coffee beans and cup quality to local culture in Jayawijaya Regency, Papua. The study was conducted using 2 factors; a. Combination of drying floor using a tarp and without sortation (DFWTS), b. Combination of drying tables and with sortation (DTWS). Drying tables were designed as two separate parts. The first part was the permanent tables, and the second part was removable boxes in dimension 80 x 80 cm located on top of the permanent tables. Descriptive analysis was conducted based on SNI 01-2907-2008 by the Indonesian Coffee and Cocoa Research Institute. The results show DTWS produce green coffee beans in compliance with SNI 01-2907-2008 at 4a grade, compared to DFWTS is rejected. Green coffee beans quality is likely to affect cup quality. DTWS obtain cup quality score 83.0 compare to DFWTS is 81.25. In conclusion, DTWS improve green coffee beans and cup quality.

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