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The positional accuracy of satellite imagery is essential for remote sensing cameras. However, vibrations and temperature changes during launch and operation can alter the exterior orientation parameters of remote sensing cameras, significantly reducing image positional accuracy. To address this issue, this article proposes an exterior orientation parameter variation real-time monitoring system (EOPV-RTMS). This system employs lasers to establish a full-link active optical monitoring path, which is free from time and space constraints. By simultaneously receiving star and laser signals with the star tracker, the system monitors changes in the exterior orientation parameters of the remote sensing camera in real time. Based on the in-orbit calibration geometric model, a new theoretical model and process for the calibration of exterior orientation parameters are proposed, and the accuracy and effectiveness of the system design are verified by ground experiments. The results indicate that, under the condition of a centroid extraction error of 0.1 pixel for the star tracker, the EOPV-RTMS achieves a measurement accuracy of up to 0.6″(3σ) for a single image. Displacement variation experiments validate that the measurement error of the system deviates by at most 0.05″ from the theoretical calculation results. The proposed EOPV-RTMS provides a new design solution for improving in-orbit calibration technology and image positional accuracy.

Laser treatments have become popular in Dermatology. In parallel to technologic development enabling the availability of different laser wavelengths, non-invasive skin imaging techniques, such as reflectance confocal microscopy (RCM), have been used to explore morphologic and qualitative skin characteristics. Specifically, RCM can be applied to cosmetically sensitive skin areas such as the face, without the need for skin biopsies. For these reasons, apart from its current use in skin cancer diagnosis, our systematic review reveals how RCM can be employed in the field of laser treatment monitoring, being particularly suitable for the evaluation of variations in epidermis and dermis, and pigmentary and vascular characteristics of the skin. This systematic review article aims to provide an overview on current applications of RCM laser treatment monitoring, while describing RCM features identified for different applications. Studies on human subjects treated with laser treatments, monitored with RCM, were included in the current systematic review. Five groups of treatments were identified and described: skin rejuvenation, scar tissue, pigmentary disorders, vascular disorders and other. Interestingly, RCM can assist treatments with lasers targeting all chromophores in the skin and exploiting laser induced optical breakdown. Treatment monitoring encompasses assessment at baseline and examination of changes after treatment, therefore revealing details in morphologic alterations underlying different skin conditions and mechanisms of actions of laser therapy, as well as objectify results after treatment.

The intrusion of obstacles onto railway tracks presents a significant threat to train safety, characterized by sudden and unpredictable occurrences. With China leading the world in high-speed rail mileage, ensuring railway security is paramount. The current laser monitoring technologies suffer from high false alarm rates and unreliable intrusion identification. This study addresses these issues by investigating high-resolution laser monitoring technology for railway obstacles, focusing on key parameters such as monitoring range and resolution. We propose an enhanced non-uniform laser scanning method, developing a laser monitoring system that reduces the obstacle false alarm rate to 2.00%, significantly lower than the 20% standard (TJ/GW135-2015). This rate is the best record for laser monitoring systems on China Railway. Our system operates seamlessly in all weather conditions, providing superior accuracy, resolution, and identification efficiency. It is the only 3D LiDAR system certified by the China State Railway Group Co., Ltd. (Certificate No. [2023] 008). Over three years, our system has been deployed at numerous points along various lines managed by the China State Railway Group, accumulating a dataset of 300,000 observations. This extensive deployment has significantly enhanced railway safety. The development and implementation of our railway laser monitoring system represent a substantial advancement in railway safety technology. Its low false alarm rate (2.00%), high accuracy (20 cm × 20 cm × 20 cm), and robust performance in diverse conditions underscore its potential for widespread adoption, promising to enhance railway safety in China and internationally.

BACKGROUND:Deep brain stimulation (DBS) requires precise and safe navigation to the chosen target. Optical measurements allow monitoring of gray-white tissue boundaries (total light intensity [TLI]) and microvascular blood flow during stereotactic procedures. OBJECTIVE:To establish the link between TLI/blood flow and anatomy along trajectories toward the ventral intermediate nucleus (Vim) and subthalamic nucleus (STN). METHODS:Stereotactic laser Doppler measurements were obtained with millimeter precision from the cortex toward the Vim (n = 13) and STN (n = 9). Optical trajectories of TLI and blood flow were created and compared with anatomy by superimposing the Schaltenbrandt-Wahren atlas on the patientsʼ pre- and postoperative images. Measurements were divided into anatomic subgroups and compared statistically. RESULTS:Typical TLI trajectories with well-defined anatomic regions could be identified for the Vim and STN. TLI was significantly lower (P < .001) and microvascular blood flow significantly higher (P = .01) in the Vim targets. Of 1285 sites, 38 showed blood flow peaks, 27 of them along the Vim trajectories. High blood flow was more common close to the sulci and in the vicinity of the caudate/putamen. Along 1 Vim trajectory, a slight bleeding was suspected during insertion of the probe and confirmed with postoperative computed tomography. CONCLUSION:Laser Doppler is useful for intraoperative guidance during DBS implantation because simultaneous measurement of tissue grayness and microvascular blood flow can be done along the trajectory with millimeter precision. Typical but different TLI trajectories were found for the Vim and STN. ABBREVIATIONS:a.u., arbitrary unitCd, caudate nucleusDBS, deep brain stimulationIC, internal capsuleLDPM, laser Doppler perfusion monitoringLSS, Leksell Stereotactic SystemSTN, subthalamic nucleusPut, putamenTLI, total light intensityVim, ventral intermediate nucleus

Aiming at the laser monitoring of the strain of the underground pile foundation of buildings, this paper establishes the intervisibility calculation model of a single monitoring hole, and optimizes the installation position of the monitoring device. The results show that the calculation results of the model are basically consistent with the measured data, which solves the problem of repeatedly adjusting the laser when measuring the maximum intervisibility in the past. Finally, the sum of the maximum intervisibility of all monitoring holes is significantly increased by optimizing the installation position.

The aim of this study was to adapt and evaluate laser Doppler perfusion monitoring (LDPM) together with custom-designed brain probes and software for continuous recording of cerebral microcirculation in patients undergoing neurosurgery. The LDPM system was used to record perfusion and backscattered light (TLI). These parameters were displayed together with the extracted heart rate (HR), pulsatility index (PI) and signal trends from adjustable time intervals. Technical evaluation was done on skin during thermal provocation. Clinical measurements were performed on ten patients undergoing brain tumour surgery. Data from 76 tissue sites were captured with a length varying between 10 s to 15 min. Statistical comparisons were done using Mann–Whitney tests. Grey and tumour tissue could be separated from white matter using the TLI signal ( p  < 0.05). The perfusion was significantly higher in grey and tumour tissue compared to white matter ( p  < 0.005). LDPM was successfully used as an intraoperative tool for monitoring local blood flow and additional parameters linked to cerebral microcirculation (perfusion, TLI, HR and PI) during tumour resection. The systems stability opens up for studies in the postoperative care of patients with, for example, traumatic brain injury or subarachnoid haemorrhage.

Manufacturing technologies using laser radiation energy are gaining increasingly new applications. It results from their numerous advantages, most of all, from the selectiveness of a laser beam within the spatial and temporal domain. Although the laser beam is a very precise tool, it restricts the tolerances of component preparation. If such increased requirements drive previous processes, it will result in the increase of manufacturing costs of these parts. Hence, solutions are sought in the mechatronics paradigm, which corrects mechanical imperfections by means of electronics and software. Examples of the above solutions are follow-up and adaptive control systems. The paper presents examples of developed and implemented control systems of laser manufacturing processes with machine vision feedback. They include remote cutting with CAM-MV and laser cladding with a thermal or geometric closed-loop.

The differences were computed using the individual percentage deviation (IPD) defined as: (ProQuest: ... denotes formula omitted.) which is a similar value to the relative standard deviation (RSD) values used to check the repeatability of the experimental measurements in the solubility studies.2 Results and Discussion The measured solubility data of acetaminophen in water and ethanol and three binary solvent mixtures of ethanol + water, the RSD for repeated experiments, the measured solubility using a previous setup and the IPD values for two solubility values are listed in Table 1. Employing such an automated setup, it is possible to measure required experimental solubility data of pharmaceuticals which usually collected by time consuming shake-flask method.25-27 The main advantages of the improved setup are; 1) a wider temperature range, 2) suitable for the solubility measurement of a highly low soluble drugs to very soluble drugs, 3) very similar measured solubilities to those determined using the common shake-flask method, 4) no need for chromophor groups on the drug molecule, 5) more repeatable results when compared with a previously reported setup, and 6) affecting parameters, such as stirrer rate, required time for equilibration, etc., could be adjusted by the user.

All thermal power plants including gas turbine (GT) of Tokyo electric company are located along Tokyo bay. If Mt. Fuji is exploded, volcanic ash is fallen down in Kanto area. If volcanic ash is inhaled into GTs, the ash would be firstly impacted and deposited onto thermal barrier coating (TBC) of the blades. Such deposition of the volcanic ash causes the delamination of the ceramic coating. In this study, TBC delamination mechanisms due to the volcanic ash deposition is discussed based upon thermal stress evaluated by a laser monitoring measurement system.

Laser monitoring has received more and more attention in many application fields thanks to its essential advantages. The analysis shows that the target speech in the laser monitoring signals is often interfered by the echoes, resulting in a decline in speech intelligibility and quality, which in turn affects the identification of useful information. The cancellation of echoes in laser monitoring signals is not a trivial task. In this article, we formulate it as a simple but effective additive echo noise model and propose a cascade deep neural networks (C-DNNs) as the mapping function from the acoustic feature of noisy speech to the ratio mask of clean signal. To validate the feasibility and effectiveness of the proposed method, we investigated the effect of echo intensity, echo delay, and training target on the performance. We also compared the proposed C-DNNs to some traditional and newly emerging DNN-based supervised learning methods. Extensive experiments demonstrated the proposed method can greatly improve the speech intelligibility and speech quality of the echo-cancelled signals and outperform the comparison methods.