Change In Horizontal Position Research Articles

The Bilinear Formula in Soliton Theory of Optical Fibers

Solitons are wave phenomena or pulses that can maintain their shape stability when propagating in a medium. In optical fibers, they become general solutions of the Non-Linear Schrödinger Equation (NLSE). Despite its mathematical complexity, NLSE has been an interesting issue. Soliton analysis and mathematical techniques to solve problems of the equation keep doing. Yan Chen (2022) introduced them based on bilinear formula for the case of the generalized NLSE extended models into third and fourth-order dispersions and cubic-quintic nonlinearity. In this paper, we review the form of the bilinear formula for the case. We re-observed a one-soliton solution based on the formula and verified the work of the last researcher. Here, the mathematical parameters of position α(0) and phase η are verified to become features of change in horizontal position and phase of one soliton in the (z, t) plane during propagation. In addition, we notice the soliton has established stability. Finally, for the condition Kerr effect focusing or the group velocity dispersion β2 more dominates, we present like the soliton trains in optical fibers under modulation instability of plane wave.

Evaluation of UV-B lighting design for phenolic production in kale plants using optical simulation with three-dimensional plant models in plant factories

Although ultraviolet-B (UV-B, 280–315 nm) radiation has been known as an effective elicitor for improving bioactive compound contents in plants, its practical application to plant factories is still in its infancy. This study aimed to develop an evaluation method for optimising the lighting design of UV-B radiation in plant factories. To this end, a prediction model of phenolic content was adapted for kale ( Brassica oleracea L. var. acephala) plants grown in a plant factory using an optical simulation in a three-dimensional plant model. The prediction model was calibrated using experimental data with different 310 nm UV-B light-emitting diode (LED) arrangements. UV-B radiation significantly enhanced the total phenolic content, total flavonoid content, UV-B absorbing pigment content, and antioxidant capacity in kale plants. In scenario analysis with variables of lighting system, such as vertical or horizontal lighting distance and lighting angle of UV-B LED, the spatial distribution of phenolic accumulation was estimated using the calibrated model and simulated UV-B radiation interception. Although the uniformity and efficiency were opposite in most scenarios, both values for phenolic production increased with changes in horizontal position. The annual yields per electrical energy consumed for producing total phenolics and flavonoids were expected to improve by 14.2 and 34.0%, respectively, assuming the addition of UV-B LED as the optimal lighting design among the scenarios. These evaluation and optimisation methods using model-based simulations will help to design custom UV-B lighting systems for the production of bioactive compounds in commercial plant factories. • UV-B radiation for phenolic production in plant factories should be optimised. • Prediction model of phenolic content in 3D plant structure was adapted. • UV-B lighting systems was evaluated with estimated radiation use efficiency. • Yield per electrical energy consumed could be improved by 14.2–34.0%. • Novel evaluation and optimisation methods of UV-B lighting systems were suggested.

Decoding 3D spatial location across saccades in human visual cortex

Visual signals are initially processed as two-dimensional images on our retina. In daily life, we make frequent eye movements and consequently the 2D retinal inputs constantly change. In addition, to perceive a 3D world, depth information needs to be reconstructed, using cues such as the binocular disparity between the 2D retinal images from both eyes. How do saccades influence the brain representation of 3D spatial locations? In an fMRI scanner, while wearing red-green anaglyph glasses to facilitate 3D perception, participants passively viewed a random dot patch that stimulated one of four 3D locations in each 16-second block. Each location was defined by its 2D position (above or below screen center; vertical information), and its depth position (in front of or behind central screen plane). We compared the amount of 2D and depth information (using multivariate pattern analysis) for no-saccade blocks (in which participants maintained stationary fixation) compared to saccade blocks (a series of guided saccades). In saccade blocks, we could decode vertical and depth information to a similar extent as in no-saccade blocks, despite the retinal changes in horizontal position induced by the saccades. Strikingly, no-saccade blocks exhibited a strong dependence on fixation position: little vertical or depth information could be decoded across blocks with different fixation positions in any visual areas during stable fixation. In contrast, on saccade blocks, both vertical and depth information were tolerant of changes in fixation position. The findings suggest that representations of 3D spatial locations may become more tolerant of fixation positions during dynamic saccades, perhaps due to active remapping which may encourage more stable representations of the world.

Application of ultrasonography to periodontal diagnosis. 1. Standardization of examination

Ultrasonic imaging equipment has been applied to periodontal diagnosis, but the standardization of this examination remains difficult. We found that a multiple reflected echo appeared on ultrasonography when the periodontal probe was inserted in the periodontal pocket. The purpose of this study was to investigate this multiple reflected echo as a reference point for ultrasonography and to measure the distances between the periodontal probe and alveolar crest in pigs by using ultrasonography. The multiple reflected echo disappeared under the following conditions: 1) when the change in horizontal position was more than 0.7 mm, 2) when the change in horizontal angle was more than 5 degrees, and 3) when the change in vertical angle was more than 20 degrees. The results in pig specimens showed that the difference in the distance from the top of the periodontal probe to the alveolar crest was less than 0.2 mm on ultrasonic and direct histological measurements. It was concluded that the multiple reflected echo of the periodontal probe can be used to standardize ultrasonographic examination.