LEDs as light source: examining quality of acquired images

2004 ◽  
Author(s):  
Rafic Bachnak ◽  
Jeng Funtanilla ◽  
Jose Hernandez
Keyword(s):  
Light Source

scholarly journals Effect of Supplementary Light Source on Quality of Grafted Tomato Seedlings and Expression of Two Photosynthetic Genes

Agronomy ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 207 ◽  
Author(s):  
Hao Wei ◽  
Jiangtao Hu ◽  
Chen Liu ◽  
Mengzhao Wang ◽  
Jin Zhao ◽  
...  
Keyword(s):  
Light Source ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Light Sources ◽  
Seedling Production ◽  
White Leds ◽  
Tomato Seedlings ◽  
Photosynthetic Genes ◽  
Supplementary Lighting

Supplementary lighting is commonly used in high-quality seedling production. In this study, grafted tomato seedlings were grown for 10 days in a glasshouse with 16-h daily supplementary lighting at 100 μmol·m−2·s−1 PPFD (Photosynthetic photon flux density) from either high-pressure sodium (HPS), metal halide (MH), far-red (FR), white LEDs (Light emitting diodes) (W), or mixed LEDs (W1R2B1, where the subscript numbers indicate the ratio of the LED chips) to determine which light sources improve the seedling quality. The control seedlings did not receive any supplementary light. Physiological parameters and the expression of genes related to photosynthesis were analyzed. The results showed that root length, biomass, number of leaves, chlorophyll (SPAD), scion dry weight to height ratio (WHR), and specific leaf weight (SLW) were the greatest for grafted seedlings grown in W1R2B1. The level of root ball formation was the greatest for seedlings grown in W1R2B1, followed by those grown in W, HPS, and MH. Seedlings grown in FR did not fare well, as they were very thin and weak. Moreover, the expression of two photosynthetic genes (PsaA and PsbA) was significantly increased by W1R2B1 and W, which suggests that the plastid or nuclear genes might be regulated. The overall results suggest that W1R2B1 was the most suitable light source to enhance the quality of grafted tomato seedlings. The results of this study could be used as a reference for seedling production in glasshouses, and may provide new insights in the research on lights affecting the development of plants.

scholarly journals Setting Standards to Promote Artificial Intelligence in Colon Mass Endoscopic Sampling

2019 ◽  
Author(s):  
Yueping Zheng ◽  
Ruizhang Su ◽  
Wangyue Wang ◽  
Sijun Meng ◽  
Hang Xiao ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Light Source ◽  
Recognition Accuracy ◽  
Poor Quality ◽  
Digestive Endoscopy ◽  
Treatment Efficiency ◽  
Picture Processing ◽  
Medical Institutions ◽  
Multiple Regions

ABSTRACTObjectiveArtificial intelligence (AI) has undeniable values in detection, characterization, and monitoring of tumors during cancer imaging. However, major AI explorations in digestive endoscopy have not been systematically planned, and more important, most AI productions are based on Single-center Studies (ScSs). ScSs result in data scarcity, redundancy as well as island effects, which leads to some limitations in applying it on endoscopy. We investigate the disadvantages of picture processing which may effect the AI detection, and make improvements in AI detection and image recognition accuracy.DesignCurrent investigation aggregates a total of 2,500 gastroenteroscopy samples from various hospitals in multiple regions and carries out deep learning.ResultsIt is found that factors inconducive to AI recognition are common such as: (a) the gastrointestinal tract is not cleaned up completely; (b) shooting angle (from left to right and the top of polyp are unexposed clearly), shooting distance (too close or too far to shoot causes the lump to be unclear), shooting light (insufficient light source or overexposed light source in mass) and unstable shooting lead to poor quality of pictures.ConclusionWe set standards for a multicenter cooperation involving three-level medical institutions from the provincial, municipal and county to improve the recognition accuracy as well as the diagnosis and treatment efficiency meanwhile.

scholarly journals Design of a Long-Pass Filter with Effects on Fluorescence Image Observation for Surgical Fluorescence Microscope Applications

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1571
Author(s):  
Jinkyu Kim ◽  
Kicheol Yoon ◽  
Kwanggi Kim
Keyword(s):  
Blood Vessels ◽  
Light Source ◽  
Oncological Surgery ◽  
Tumor Removal ◽  
Diagnostic Image ◽  
Pass Filter ◽  
Fluorescence Image ◽  
Surgical Microscope ◽  
External Light Source

The goal of oncological surgery is to completely remove the tumor. Tumors are often difficult to observe with the naked eye because of the presence of numerous blood vessels and the fact the colors of the tumor and blood vessels are similar. Therefore, a fluorescent contrast medium using a surgical microscope is used to observe the removal status of the tumor. To observe the tumor removal status using a fluorescent contrast agent, fluorescence is expressed in the tumor by irradiating with an external light source, and the expressed tumor can be confirmed through a surgical microscope. However, not only fluorescence-expressed tumors are observed under a surgical microscope, but images from an external light source are also mixed and observed. Therefore, since the surgical microscope is connected to a filter, the quality of the diagnostic image is not uniform, and it is difficult to achieve a clear observation. As a result, an asymmetric image quality phenomenon occurs in the diagnostic images. In this paper, a filter with high clarity that provides a symmetrical observation of diagnostic images is developed and manufactured.

scholarly journals Using a Fuzzy Light Sensor to Improve the Efficiency of Solar Panels

2018 ◽  
Vol 31 ◽  
pp. 01007
Author(s):  
Suryono Suryono ◽  
Jatmiko Endro Suseno ◽  
Ainie Khuriati Riza Sulistiati ◽  
Tahan Prahara
Keyword(s):  
Light Source ◽  
Power Efficiency ◽  
Solar Panel ◽  
Source Tracking ◽  
Fuzzy Membership ◽  
Solar Panels ◽  
Light Sensor ◽  
Sensor Property ◽  
Tracking Model

Solar panel efficiency can be increased by improving the quality of photovoltaic material, the effectiveness of electronic circuit, and the light source tracking model. This research is aimed at improving the quality of solar panels by tracking light source using a fuzzy logic sensor. A fuzzy light sensor property is obtained from two LDR (light dependent resistor) light sensors installed in parallel to each other and is given a light separator in between them. Both sensors are mounted on a solar panel. Sensor output is acquired using a 12 bit ADC from an ATSAM3XE microcontroller and is then sent to a computer using WIFI radio. A PID (Proportional-Integral-Derivative) control algorithm is used to manage the position of the solar panel in line with the input given by the fuzzy light sensor. This control mechanism works based on the margin of fuzzy membership from both sensors that is used to move a motor DC that in turn moves the solar panel. Experimental results show a characteristically symmetrical fuzzy membership of both sensors with a reflected correlation of R=0.9981 after gains from both sensors are arranged with a program. Upon being tested in the field, this system was capable of improving the performance of solar panels in gaining power compared to their original fixed position. The discrepancy was evident when the angle of incoming sunlight approached both 0° and 180°. Further calculations of data acquired by the fuzzy light sensor show increased solar panel power efficiency by up to 5.6%.

scholarly journals Microscope Illumination: LEDs are the Future

2011 ◽  
Vol 19 (4) ◽  
pp. 18-21
Author(s):  
James Beacher
Keyword(s):  
Fluorescence Microscopy ◽  
Light Source ◽  
Phase Contrast ◽  
Life Science ◽  
Science Research ◽  
Bright Field ◽  
Clinical Screening ◽  
Different Types ◽  
Differential Phase Contrast

Light microscopes in laboratories and hospitals are used for examining many different types of samples—from industrial research to life-science research and clinical screening. These procedures use conventional bright-field, differential phase contrast (DIC), and fluorescence microscopy among other techniques. In all cases, the light source on the microscope has a crucial influence on the quality of images viewed and the conclusions reached.

The influence of metal halide and high-pressure sodium lamps during photoperiod extension on the allocation of carbon between lignin and cellulose in black spruce seedlings

1988 ◽  
Vol 18 (7) ◽  
pp. 962-964 ◽  
Author(s):  
Hank A. Margolis ◽  
Jacques Bégin ◽  
Richard Beeson ◽  
Pierre Bellefleur
Keyword(s):  
High Pressure ◽  
Light Source ◽  
Black Spruce ◽  
Metal Halide ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Seedling Height ◽  
Active Radiation ◽  
Seedling Biomass

Containerized black spruce seedlings (Piceamariana (Mill.) B.S.P.) were grown at the greenhouse at CIP Inc., Harrington, Québec, from February until May, 1987. We wished to test whether differences in the quantity and quality of light received from two commercially available lamps during photoperiod extension would alter the allocation of carbon between lignin and cellulose in shoots and roots. Photoperiods were extended from 17:00 to 01:00 using either metal halide and high-pressure sodium lamps together or high-pressure sodium lamps alone. At night, the treatment using both types of lamp together increased the photon flux density of blue light (400–500 nm) at seedling height 10-fold, from 0.32 to 3.2 μE m−2 s−1. Photosynthetically active radiation was increased 4-fold, from 4.5 to 17.9 μE m−2 s−1. Total seedling biomass did not differ statistically between light treatments at any given time. However, seedling biomass averaged over all times was statistically higher (p ≤ 0.03) for seedlings in the treatment using both types of lamp together. Percent lignin, percent cellulose, and lignin to cellulose ratios were not significantly affected by the light source used during photoperiod extension. As expected, percent lignin and percent cellulose in shoots and roots increased significantly with time. The percentage of seedlings judged unacceptable because of spiralized stems was not affected by light source and averaged 21.9%.

scholarly journals ANALISIS KETAHANAN PRODUK SOLAR CELL BERBANTUAN SOFTWARE LOGGER PRO

2019 ◽  
Vol 5 (2) ◽  
pp. 73
Author(s):  
Hamzah Hamzah ◽  
Moh. Toifur
Keyword(s):  
Solar Cell ◽  
Light Source ◽  
Fill Factor ◽  
Slope Angle ◽  
Cell Type ◽  
Exponential Equation ◽  
Equation Analysis ◽  
Lamp Bulb

ABSTRAKPenelitian ini bertujuan untuk menentukan kualitas solar cell pada nilai fill factor (ff) dan efisiensinya ( ). Data tegangan Vi dan Ii diambil secara otomatis menggunakan software logger pro dan menggunakan analisis persamaan eksponensial . Data diambil dari solar cell merk polikristal type (99×69) mm2 yang dipaparkan di depan sumber cahaya lampu bohlam philips 100W/220V sejauh 18 cm pada Ir sebesar 983, 344 W/m2. Nilai Pmax terbesar besar berada pada sudut kemiringan 30o sebesar 0,0231 watt. ff yaitu 67%, efisiensi 22%. Pada sudut 30o tersebut arah cahaya datang tegak lurus dengan bidang solar cell. Sedangkan ff terendah kemiringan 70o yaitu 0,5362 dan efisiensi 13%. Kata kunci: Fill factor dan efisiensi solar cell; logger pro. ABSTRACTThis study aims to determine the quality of solar cell on the value of the fill factor (ff) and efficiency (h). The voltage data Vi and Ii are taken automatically using logger pro software and using exponential equation analysis. The data was taken from polycrystalline solar cell type (99×69) mm2 which was presented in front of the light source of Philips lamp bulb 100W/220V as far as 18 cm at Ir of 983, 344 W/m2. The largest Pmax value is at a slope angle of 30o of 0,0231 watts. ff is 67%, efficiency is 22%. At the 30o angle the direction of the light comes perpendicular to the plane of the solar cell. While the lowest ff is 70o, which is 0,5362 and efficiency is 13%. Keywords: Fill factor and efficiency solar cell; logger pro.

scholarly journals Curing Quality of Composites as Influenced by the Filler Content, Light Source and Curing Time

Dentistry ◽  
2011 ◽  
Vol 01 (01) ◽  
Author(s):  
Boniek Castillo Dutra Borges ◽  
Ana Isabelle Salvador Groninger ◽  
Giulliana Panfiglio Soares
Keyword(s):  
Light Source ◽  
Filler Content ◽  
Curing Time

scholarly journals Luxmeter Design with Proximity Sensor to Efficiently Test Light Intensity and Distance on Lamp Operation in Hospitals

2021 ◽  
Vol 1 (1) ◽  
pp. 20-25
Author(s):  
Dika Surya Rizky Rahayu ◽  
M. Ridha Mak'ruf ◽  
Syaifudin Syaifudin
Keyword(s):  
Light Intensity ◽  
Light Source ◽  
Calibration Method ◽  
Operating Table ◽  
Proximity Sensor ◽  
Cutting Surface ◽  
Sensor Module ◽  
Distance Setting

The lighting of the operating/surgical site depends on the quality of the lighting from the overhead light source and the reflection from the curtain. Light measurement on the operating table is very necessary because it generates light that is irradiated into the cutting wound without dazzling the cutting surface so that pathological conditions can be recognized and must provide depth contrast and anatomical relationships, to ensure this proper calibration method is needed. Long-term use of medical devices can cause changes in accuracy. Therefore, the author makes a tool to measure the intensity of light which is equipped with a distance meter. The purpose of this study was to develop a measuring instrument for measuring the intensity of light in operating lamps, namely a luxmeter by making Luxmeter equipped with a TFT Display Distance Sensor. This tool uses an ultrasonic sensor HC-SR04 to measure the distance between the light source and the sensor module and the MAX44009 sensor to measure the light intensity of the operating lamp displayed on the TFT screen. Based on the module distance setting to the roll meter, the distance error value for the measurement of the Surabaya electromedical engineering workshop lamp at the 75 cm roll meter distance setting is 0.0127% for the 100 cm roll meter distance setting is 0.0045%. The error rate of the light intensity module on the results of the measurement of light intensity on the luxmeter by setting the roll meter distance of 75 cm between the tool and the lamp of the electromedical engineering workshop is getting an error value of 0.082% lux and for the light intensity on the results of the measurement of light intensity on the luxmeter with a roll meter distance setting of 100 cm between the tool and the lamp in the electromedical engineering workshop, that is, the error value of lux is 0.055%. The design of a luxmeter equipped with a proximity sensor can measure the intensity of light and the distance between the tool and the light source and can assist in the learning process with a more effective Luxmeter design that will assist electromedics in testing operating lamps in hospitals to be more efficient.

Light source based on a 100 mm-long monolithic undulator magnet with a very short 4 mm-period length

2019 ◽  
Vol 26 (6) ◽  
pp. 1902-1910 ◽  
Author(s):  
Shigeru Yamamoto ◽  
Shigeru Kashiwagi ◽  
Shinichi Masuda ◽  
Nobuhiko Nakanii ◽  
Tomonao Hosokai ◽  
...  
Keyword(s):  
Light Source ◽  
Field Measurements ◽  
Period Length ◽  
Calculated Spectrum ◽  
Fundamental Radiation ◽  
Novel Method ◽  
Electron Photon ◽  
Photon Science

A novel method to fabricate undulator magnets of a-few-millimetre-period length is being explored. Plate-type magnets, 100 mm-long with 4 mm-period length, have been successfully fabricated. They produce an undulator field of approximately 3 kG at a gap of 1.6 mm. Prototype undulators based on this technology have been constructed. Field measurements and characterization show that the quality of the undulator field of these plate magnets is sufficient for an undulator light source, and the calculated spectrum shows that the fundamental radiation emitted from this field is quite satisfactory. Test experiments for light generation using a real electron beam have been carried out at a test accelerator at the Research Center for Electron Photon Science (ELPH), Tohoku University, Japan, which is able to realize optics conditions to accept a very short gap of ∼1.6 mm. First observation and characterization of blue light was successfully accomplished.

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