New Method of Indoor High Accuracy Imaging Positioning Based on LED Light Source

In this paper, I will review the capabilities of magnetic imaging (also called Zeeman-Doppler imaging) to reconstruct spot distributions of surface fields from sets of rotationnally modulated Zeeman signatures in circularly polarised spectral lines. I will then outline a new method to measure small amplitude magnetic signals (typically 0.1% for cool active stars) with very high accuracy. Finally, I will present and comment new magnetic images reconstructed from data collected in 1993 December at the Anglo-Australian Telescope (AAT).

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A Design of High-Accuracy Displacement Measurement Instrument from Principles of Optics

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.2924 ◽

2012 ◽

Vol 170-173 ◽

pp. 2924-2928

Author(s):

Sheng Biao Chen ◽

Yun Zhi Tan

Keyword(s):

Measurement Instrument ◽

High Accuracy ◽

Mechanical Tests ◽

Total Reflection ◽

Displacement Measurement ◽

New Method ◽

Water Volume ◽

Water Drainage ◽

Accuracy Of Measurement ◽

Better Than

In order to measure the water drainage volume in soil mechanical tests accurately, it develop a new method which is based on principles of optics. And from both physical and mathematic aspects, it deduces the mathematic relationship between micro change in displacement and the increment projected on screen. The result shows that total reflection condition is better than refraction condition. What’s more, the screen could show the water volume micro variation clearly, so it can improve the accuracy of measurement.

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Subcell Operation and Long‐Term Stability Analysis of Perovskite‐based Tandem Solar Cells using a Bichromatic LED Light Source

Solar RRL ◽

10.1002/solr.202100311 ◽

2021 ◽

Author(s):

Marko Jošt ◽

Gašper Matič ◽

Eike Köhnen ◽

Bor Li ◽

Boštjan Glažar ◽

...

Keyword(s):

Solar Cells ◽

Stability Analysis ◽

Light Source ◽

Tandem Solar Cells ◽

Led Light ◽

Term Stability ◽

Long Term Stability

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Analysis on High-Power Seaport LED Luminaire with Uniform Light Distribution Based on Optimized Lens and Heatsink

Applied Sciences ◽

10.3390/app11094035 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4035

Author(s):

Jinsheon Kim ◽

Jeungmo Kang ◽

Woojin Jang

Keyword(s):

Light Source ◽

High Power ◽

Heat Dissipation ◽

Light Emitting Diode ◽

Light Distribution ◽

Light Sources ◽

Led Light ◽

High Power Led ◽

Distribution Requirement ◽

Lighting Application

In the case of light-emitting diode (LED) seaport luminaires, they should be designed in consideration of glare, average illuminance, and overall uniformity. Although it is possible to implement light distribution through auxiliary devices such as reflectors, it means increasing the weight and size of the luminaire, which reduces the feasibility. Considering the special environment of seaport luminaires, which are installed at a height of 30 m or more, it is necessary to reduce the weight of the device, facilitate replacement, and secure a light source with a long life. In this paper, an optimized lens design was investigated to provide uniform light distribution to meet the requirement in the seaport lighting application. Four types of lens were designed and fabricated to verify the uniform light distribution requirement for the seaport lighting application. Using numerical analysis, we optimized the lens that provides the required minimum overall uniformity for the seaport lighting application. A theoretical analysis for the heatsink structure and shape were conducted to reduce the heat from the high-power LED light sources up to 250 W. As a result of these analyses on the heat dissipation characteristics of the high-power LED light source used in the LED seaport luminaire, the heatsink with hexagonal-shape fins shows the best heat dissipation effect. Finally, a prototype LED seaport luminaire with an optimized lens and heat sink was fabricated and tested in a real seaport environment. The light distribution characteristics of this prototype LED seaport luminaire were compared with a commercial high-pressure sodium luminaire and metal halide luminaire.

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Barycentric prolate interpolation and pseudospectral differentiation

Numerical Algorithms ◽

10.1007/s11075-020-01057-7 ◽

2021 ◽

Author(s):

Yan Tian

Keyword(s):

Boundary Value Problem ◽

Convergence Rates ◽

Boundary Value ◽

High Accuracy ◽

Second Order ◽

New Method ◽

Numerical Examples ◽

Helmholtz Problem ◽

Collocation Scheme

AbstractIn this paper, we provide further illustrations of prolate interpolation and pseudospectral differentiation based on the barycentric perspectives. The convergence rates of the barycentric prolate interpolation and pseudospectral differentiation are derived. Furthermore, we propose the new preconditioner, which leads to the well-conditioned prolate collocation scheme. Numerical examples are included to show the high accuracy of the new method. We apply this approach to solve the second-order boundary value problem and Helmholtz problem.

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A New Method for Aggregate Proportion Design of Mixture

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.178-181.1250 ◽

2012 ◽

Vol 178-181 ◽

pp. 1250-1253

Author(s):

Yu Hua Li ◽

Kai Huang ◽

Ying Zhen Gao

Keyword(s):

Iterative Algorithm ◽

Accurate Result ◽

High Accuracy ◽

New Method ◽

Equation Method ◽

Normal Equation ◽

Improved Method ◽

Mixture Ratio ◽

Target Value ◽

Initial Target

When we make design of mixture ratio, we always use normal equation method (NEM), but the solution value of that method may doesn’t meet our demand. When we use the new method that proposed in this paper, we can solve the problem. The new method makes an improvement for NEM. By iterative algorithm, the new method uses the gradation data calculated by NEM as initial target value, canceling the relevant aggregate if the result of proportion is negative, and setting the gradation to the boundary value if the target value goes beyond limits. According to the adjusted object value, using NEM again, the new aggregate proportion can be solved. Then the new gradation of mixture will come into being the next target value. Finally, the accurate result will meet our need. The new improved method has good engineering applicability and high accuracy

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Photothermal Therapy Using Gold Nanorods and Near-Infrared Light in a Murine Melanoma Model Increases Survival and Decreases Tumor Volume

Journal of Nanomaterials ◽

10.1155/2014/450670 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 19

Author(s):

Mary K. Popp ◽

Imane Oubou ◽

Colin Shepherd ◽

Zachary Nager ◽

Courtney Anderson ◽

...

Keyword(s):

Light Source ◽

Gold Nanorods ◽

Photothermal Therapy ◽

Near Infrared ◽

Tumor Volume ◽

Infrared Light ◽

Led Light ◽

Murine Melanoma ◽

Nir Light ◽

Melanoma Model

Photothermal therapy (PTT) treatments have shown strong potential in treating tumors through their ability to target destructive heat preferentially to tumor regions. In this paper we demonstrate that PTT in a murine melanoma model using gold nanorods (GNRs) and near-infrared (NIR) light decreases tumor volume and increases animal survival to an extent that is comparable to the current generation of melanoma drugs. GNRs, in particular, have shown a strong ability to reach ablative temperatures quickly in tumors when exposed to NIR light. The current research tests the efficacy of GNRs PTT in a difficult and fast growing murine melanoma model using a NIR light-emitting diode (LED) light source. LED light sources in the NIR spectrum could provide a safer and more practical approach to photothermal therapy than lasers. We also show that the LED light source can effectively and quickly heatin vitroandin vivomodels to ablative temperatures when combined with GNRs. We anticipate that this approach could have significant implications for human cancer therapy.

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