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Aiming to meet the growing need for automated harvesting, an automatic alignment method based on Euclidean clustering and K-means clustering is proposed to address issues of driver fatigue and inaccurate driving in manually operated corn harvesters. Initially, the corn field environment is scanned using LiDAR to obtain point cloud data, which are then subjected to pass-through filtering and statistical filtering to remove noise and non-corn contour points. Subsequently, Euclidean clustering and K-means clustering methods are applied to the filtered point cloud data. To validate the impact of Euclidean clustering on subsequent clustering, two separate treatments of the obtained point cloud data were conducted during experimental validation: the first used the K-means clustering algorithm directly, while the second involved performing Euclidean clustering followed by K-means clustering. The results demonstrate that the combined method of Euclidean clustering and K-means clustering achieved a success rate of 81.5%, representing a 26.5% improvement over traditional K-means clustering. Additionally, the Rand index increased by 0.575, while accuracy improved by 57% and recall increased by 61%. [ABSTRACT FROM AUTHOR]

In corpus-based interpreting studies, typical challenges exist in the time-consuming and labour-intensive nature of transcribing spoken data and in identifying prosodic properties. This paper addresses these challenges by exploring methods for the automatic compilation of multimodal interpreting corpora, with a focus on English/Chinese Consecutive Interpreting. The results show that: 1) automatic transcription can achieve an accuracy rate of 95.3% in transcribing consecutive interpretations; 2) prosodic properties related to filled pauses, unfilled pauses, articulation rate, and mispronounced words can be automatically extracted using our rule-based programming; 3) mispronounced words can be effectively identified by employing Confidence Measure, with any word having a Confidence Measure lower than 0.321 considered as mispronounced; 4) automatic alignment can be achieved through the utilisation of automatic segmentation, sentence embedding, and alignment techniques. This study contributes to interpreting studies by broadening the empirical understanding of orality, enabling multimodal analyses of interpreting products, and providing a new methodological solution for the construction and utilisation of multimodal interpreting corpora. It also has implications in exploring applicability of new technologies in interpreting studies. [ABSTRACT FROM AUTHOR]

Free-Space Optical (FSO) communications have emerged as a viable solution to complement conventional communication technologies, mainly due to their high transmission rates, ease of implementation, low cost, and unlicensed spectrum. However, FSO technology faces significant challenges in achieving the initial alignment between the transceivers without pre-alignment or extensive manual configuration. The manual alignment process is extremely time-consuming and current automated solutions typically employ an infrared (IR) beam followed by an IR camera, which, besides increasing the transceiver cost, also requires an initial pre-convergence stage resorting to complementary coarse alignment technologies (e.g. Global Positioning System (GPS)). To tackle this challenge, we propose a novel methodology for the automatic alignment of FSO systems that does not require pre-convergence and avoids the use of costly IR cameras. The proposed alignment method is based on the application of computer vision (CV) during the transmission of a visible beacon and the utilization of pointing, acquisition and tracking (PAT) mechanisms. This solution is cost-effective, as the initial coarse alignment is carried out using visible light equipment, such as a standard CMOS camera and a visible beacon. Furthermore, it does not require any additional pre-convergence stage, since the alignment is based on characteristics acquired through CV during the transmission of the visible beacon, specifically the angle of inclination and the count of the number of pixels associated with the beacon. Additionally, the alignment process allows for a maximum angular misalignment of ±3.3 degrees between the optical antennas (OA), corresponding to a coverage area of $5.3 \text {m}^{2}$ at a distance of 20 meters. Finally, using this method, the successful alignment of an FSO system is demonstrated in a free-space link with 20 meters distance for different ambient light conditions, with real-time transmission at 16 Gbps.

Aiming to meet the growing need for automated harvesting, an automatic alignment method based on Euclidean clustering and K-means clustering is proposed to address issues of driver fatigue and inaccurate driving in manually operated corn harvesters. Initially, the corn field environment is scanned using LiDAR to obtain point cloud data, which are then subjected to pass-through filtering and statistical filtering to remove noise and non-corn contour points. Subsequently, Euclidean clustering and K-means clustering methods are applied to the filtered point cloud data. To validate the impact of Euclidean clustering on subsequent clustering, two separate treatments of the obtained point cloud data were conducted during experimental validation: the first used the K-means clustering algorithm directly, while the second involved performing Euclidean clustering followed by K-means clustering. The results demonstrate that the combined method of Euclidean clustering and K-means clustering achieved a success rate of 81.5%, representing a 26.5% improvement over traditional K-means clustering. Additionally, the Rand index increased by 0.575, while accuracy improved by 57% and recall increased by 61%.

Whispering-gallery mode microresonators have gained wide popularity as experimental platforms for different applications, ranging from biosensing to nonlinear optics. Typically, the resonant modes of dielectric microresonators are stimulated via evanescent wave coupling, facilitated using tapered optical fibers or coupling prisms. However, this method poses serious shortcomings due to fabrication and access-related limitations, which could be elegantly overcome by implementing a free-space coupling approach; although additional alignment procedures are needed in this case. To address this issue, we have developed a new algorithm to excite the microresonator automatically. Here, we show the working mechanism and the preliminary results of our experimental method applied to a home-made silica microsphere, using a visible laser beam with a spatial light modulator and a software control. [ABSTRACT FROM AUTHOR]

The field harvesting process of harvesting machinery is often affected by high workload and environmental factors that can impede/delay manual rowing, thereby leading to lower efficiency and quality in the residual film collector. To address this challenge, an automatic rowing control system using the 4mz-220d self-propelled residual film collector as the experimental carrier was proposed in this study. Cotton stalks in the ridges were chosen as the research object, and a comprehensive application of key technologies, machinery, and electronic control was used, thereby incorporating a pure tracking model as the path-tracking control method. To achieve the automatic rowing function during the field traveling process, the fuzzy control principle was implemented to adjust the forward distance within the pure tracking model dynamically, and the expected steering angle of the steering wheel was determined based on the kinematic model of the recovery machine. The MATLAB/Simulink software was utilized to simulate and analyze the proposed model, thus achieving significant improvements in the automation level of the residual film collector. The field harvesting tests showed that the average deviation of the manual rowing was 0.144 m, while the average deviation of the automatic rowing was 0.066 m. Moreover, the average lateral deviation of the automatic rowing was reduced by 0.078 m with a probability of deviation within 0.1 m of 95.71%. The research study demonstrated that the designed automatic rowing system exhibited high stability and robustness, thereby meeting the requirements of the autonomous rowing operations of residual film collectors. The results of this study can serve as a reference for future research on autonomous navigation technology in agriculture. [ABSTRACT FROM AUTHOR]

In order to improve the communication quality of visible light downlink, an automatic alignment system for visible light communication based on OpenMV is designed in this study. The system realizes automatic recognition of indoor white LED is based on image processing and color recognition. The system uses gray-scale centroid method to determine the centroid coordinates of white LED, and the PID algorithm is used to drive steering gears to achieve the tracking of the indoor white light LED. The experimental results show that the automatic alignment system of visible light communication can realize the automatic alignment of white LED under various motion trajectories at the receiving distance of 2 m, and the maximum alignment angle error is less than 0.534°. In addition, whether the white LED is blocked or there is an interfering light source, system can still maintain the good tracking effect, indicating that system has good robustness. [ABSTRACT FROM AUTHOR]

With the massive growth of the software sector as well as the erratic needs of end users, agent-based information systems and Model Driven Architecture (MDA) approach are among the liveliest and significant fields of experimentation and improvement to emerge in the recent decade. In this vein, we suggest in this research an innovative method that automates the construction and the generation processes of the interaction multi-agent models from the business requirements engineering models at the MDA highest abstraction levels. So, our defiance is to align the Agent Modeling Language (AML) Communicative Interaction diagram with the E3value model dealing with the MDA approach. The ATLAS-Transformation Language (ATL) is applied to automate the model alignment process. The goal is to reduce project effort, time, and development costs as all alignment process is automatically done, boosting the chances of being more competitive in the software business. [ABSTRACT FROM AUTHOR]

The possibility of automatically aligning the transmission electron microscope (TEM) is explored using an approach based on artificial intelligence (AI). After presenting the general concept, we test the method on the first step of the alignment process which involves centering the condenser aperture. We propose using a convolutional neural network (CNN) that learns to predict the x and y-shifts needed to realign the aperture in one step. The learning data sets were acquired automatically on the microscope by using a simplified digital twin. Different models were tested and analysed to choose the optimal design. We have developed a human-level estimator and intend to use it safely on all apertures. A similar process could be used for most steps of the alignment process with minimal changes, allowing microscopists to reduce the time and training required to perform this task. The method is also compatible with continuous correction of alignment drift during lengthy experiments or to ensure uniformity of illumination conditions during data acquisition. • Generalizable application of artificial intelligence to microscope alignment. • Experimental demonstration of condenser aperture alignment by convolutional neural networks (CNNs). • Exploration of a CNN architecture optimization on a the case study of condenser aperture alignment. [ABSTRACT FROM AUTHOR]

Whispering-gallery mode microresonators have gained wide popularity as experimental platforms for different applications, ranging from biosensing to nonlinear optics. Typically, the resonant modes of dielectric microresonators are stimulated via evanescent wave coupling, facilitated using tapered optical fibers or coupling prisms. However, this method poses serious shortcomings due to fabrication and access-related limitations, which could be elegantly overcome by implementing a free-space coupling approach; although additional alignment procedures are needed in this case. To address this issue, we have developed a new algorithm to excite the microresonator automatically. Here, we show the working mechanism and the preliminary results of our experimental method applied to a home-made silica microsphere, using a visible laser beam with a spatial light modulator and a software control.

The field harvesting process of harvesting machinery is often affected by high workload and environmental factors that can impede/delay manual rowing, thereby leading to lower efficiency and quality in the residual film collector. To address this challenge, an automatic rowing control system using the 4mz-220d self-propelled residual film collector as the experimental carrier was proposed in this study. Cotton stalks in the ridges were chosen as the research object, and a comprehensive application of key technologies, machinery, and electronic control was used, thereby incorporating a pure tracking model as the path-tracking control method. To achieve the automatic rowing function during the field traveling process, the fuzzy control principle was implemented to adjust the forward distance within the pure tracking model dynamically, and the expected steering angle of the steering wheel was determined based on the kinematic model of the recovery machine. The MATLAB/Simulink software was utilized to simulate and analyze the proposed model, thus achieving significant improvements in the automation level of the residual film collector. The field harvesting tests showed that the average deviation of the manual rowing was 0.144 m, while the average deviation of the automatic rowing was 0.066 m. Moreover, the average lateral deviation of the automatic rowing was reduced by 0.078 m with a probability of deviation within 0.1 m of 95.71%. The research study demonstrated that the designed automatic rowing system exhibited high stability and robustness, thereby meeting the requirements of the autonomous rowing operations of residual film collectors. The results of this study can serve as a reference for future research on autonomous navigation technology in agriculture.

Most of the existing fingerprint indexing methods are based on real-valued features, which is compute and storage intensive for large- scale databases. In order to speed up the retrieval process and obtain real- time response results from large-scale databases, a novel fingerprint indexing method based on supervised deep hash is proposed in this paper. This method combines domain knowledge with self-attention deep hash model. The domain knowledge is used for fingerprint image preprocessing to obtain the binary skeleton images, and the self-attention deep hash module maps the binary skeleton images to Hamming space to get binary embeddings for indexing. In the feature extraction module, Transformer structure is used to replace convolutional neural network to extract fingerprint minutiae features. In addition, an automatic alignment module is added to the model and a STN-AE structure is designed to assist in training the module. Experiments conducted on public datasets such as NIST4, NIST14, FVC2000, FVC2002 and FVC2004, have confirmed that this method is effective in improving the retrieval speed and reducing storage consumption. [ABSTRACT FROM AUTHOR]

What is commonly considered as an epenthetic vowel can actually refer to at least two different realities: phonological epenthesis or phonetic excrescence. French schwa, noted [ә], is a vowel alternating with zero and limited to unstressed syllables that can appear word-internally or word-finally. This paper presents an extensive description of the distribution of word-final schwa in Standard French in order to shed light on its nature: is it an intrusive vowel or a full epenthetic vowel? To that extent, three large corpora of French containing more than 110 hours of speech were used to establish the presence of word-final schwa as a function of sociolinguistics, orthography, phonotactics and phonetics. Our conclusions are that word-final schwa is impacted by speech style, gender, orthography, phonotactics (i.e., the number of adjacent consonants and their sonority profile), and the phonological properties of the codas. However, speech rate does not impact word-final schwa realization. The specific results lead us to suggest that word-final schwa in Standard French shares similarities with intrusive vowels but ultimately behaves like a legit epenthetic vowel.

In this paper we present a novel method for recovering high‐resolution spatially‐varying isotropic surface reflectance of a planar exemplar from a flash‐lit close‐up video sequence captured with a regular hand‐held mobile phone. We do not require careful calibration of the camera and lighting parameters, but instead compute a per‐pixel flow map using a deep neural network to align the input video frames. For each video frame, we also extract the reflectance parameters, and warp the neural reflectance features directly using the per‐pixel flow, and subsequently pool the warped features. Our method facilitates convenient hand‐held acquisition of spatially‐varying surface reflectance with commodity hardware by non‐expert users. Furthermore, our method enables aggregation of reflectance features from surface points visible in only a subset of the captured video frames, enabling the creation of high‐resolution reflectance maps that exceed the native camera resolution. We demonstrate and validate our method on a variety of synthetic and real‐world spatially‐varying materials. [ABSTRACT FROM AUTHOR]

This study aims to identify certain phonetic and lexical determinants of major durational variations in spontaneous speech. Three duration samples (SHORT, STANDARD and LONG) were extracted from a corpus of French conversational speech. With high concentrations of liquids and glides in SHORT, vowels show strong temporal distortion towards lengthening. Conversely, fricatives and plosives represent stable temporal supports. Some function words tend to promote reduction while the lengthening of phonemes is due, in large part, to their presence in some frequent items in conversation (discourse markers, interjections). The duration of specific phonemes (/l/,/Ê€/,/w/,/m/) is strongly conditioned by their lexical or communicative context. Phonemic durations are therefore determined, among other things, by the nature of phonemes and by the properties of lexicon and its use in conversation. [ABSTRACT FROM AUTHOR]

In the concrete implementation of the fuzzy vault algorithm, the geometric hash method is a common technique for automatic calibration of biometric templates. For the fuzzy problem of parameter acquisition, the matching accuracy of fuzzy vault template is affected in the three parameters: the pixel size, hash table and hash table quantization parameters (α and β). The single factor experiment method obtains the optimal range of these three parameters, and the extraction range of the fuzzy point and the selection rule of the base point distance are improved for the fuzzy vault algorithm. Finally, based on the FVC fingerprint database, their matching precision is compared for the algorithm before and after optimization. The experimental results show that the false rejection rate (FRR) of the optimized algorithm is reduced by at least 9.84%, and the false acceptance rate (FAR) is reduced by at least 7.12%, indicating that the optimization scheme improves the matching accuracy of the algorithm. The algorithm has certain robustness and practicability. [ABSTRACT FROM AUTHOR]

The omental bursa (OB) is a complex upper abdominal structure in adults. Its morphological complexity stems from embryonic development. Approximately 200 years ago, the first theory regarding OB development was reported, describing that the OB developed from changes in the position of the stomach and its dorsal mesentery. Thereafter, the second theory reported that the OB originated from three recesses: the right pneumato‐enteric recess (rPER), hepato‐enteric recess (HER), and pancreatico‐enteric recess (PaER). However, the first theory, focusing on the rotation of the stomach, is still described in certain modern embryology textbooks. These two coexisting embryological theories deter the understanding of the anatomical complexity of the OB. This study aimed to unify these two theories into realistic illustrations. Approximately 10 samples per stage among Carnegie stage (CS) 13 and CS21 were microscopically observed and histological serial sections of the representative samples were aligned using the new automatic alignment method. The aligned images were segmented computationally and reconstructed into 3D models. The rPER and the HER encompassed the right half circumference of the esophagus and the stomach at CS13 and CS14, the PaER spread dorsal to the stomach and formed a discoid shape at CS15 and CS16, the infracardiac bursa (ICB) was separated by the diaphragm at CS17 and CS18, and the fourth recess, which we called the greater omental recess (GOR), extended caudally from the PaER among CS19 and CS21. The present results indicate that the fourth recess is also the origin of the OB. These two theories over 200 years can be generally unified into one embryological description indicating a new recess as the origin of the OB. [ABSTRACT FROM AUTHOR]

Aiming at the alignment problem of non-transparent template in microelectronic packaging, the optical design and alignment algorithm were researched, and the bidirectional machine vision alignment system was proposed. The sizes of mold plates were extended by setting up a transparent calibration plate parallel to mold plates to be aligned, and the upper and the lower mold plate were placed in different position for photograph. The problem that the camera could not be installed in narrow space and the metal mold plates were not perspective were overcome, which realized the indirect alignment, and an automatic alignment system was developed. Based on machine vision, the images were acquired through bidirectional vision system and the edge images of mold plate were extracted by the image matching algorithm and Canny operator respectively for the initial extraction and the second extraction at the sub-pixel level. Then the planimetric position error of mold plate pair was calculated indirectly through coordinate transformation, and the error was used to drive XYR workbench for alignment control. The experimental results show that the high precision automatic alignment of the non-transparent mold plates can be realized in practical operation environment. [ABSTRACT FROM AUTHOR]

In order to improve the quality and efficiency of the mechanical harvest of subterranean crops, and to solve the problems of high cost, low efficiency, inconvenient data collection and greatly affected by weather on the field test of harvest machines for crops under soil in China, an automatic alignment digging harvest test bench for crops under soil harvesting is designed in this paper. The test bench is mainly composed of a transmission device, speed adjustment device, off-centerline distance adjustment device, root fixed and plant spacing adjustment device, deviation detection device, hydraulic correction actuator and digging simulation device, measurement control system and hydraulic system. The overall structure and working principle of the test bench are briefly analyzed, and the structural design and parameter analysis of key components are especially introduced. A gantry with adjustable front and back distance and height between the deviation detection device and the digging simulation device is designed. Using four-bar linkage, a deviation detection device is designed to detect the distribution of subterranean crops in the soil and transfer it to the controller. An digging simulation device with resistance is designed to simulate the soil resistance of the digging device during the process of digging and harvesting. A device with root fixing, plant spacing and off-centerline distance adjustment is designed to simulate the actual plant spacing, off-centerline distance and other growth conditions in the field. The mathematical relationship between the expansion and contraction of the hydraulic cylinder and the moving distance of the digging mechanism is established. The hardware of the measurement and control system is mainly composed of control box, computer, pressure sensor, flow sensor, displacement sensor, speed sensor, hydraulic solenoid valve, hydraulic cylinder and high-speed camera. The software adopts the fixed dual-threshold dead-zone PD control algorithm. In order to improve the generality of the test bench, it is only to replace the original detecting rod with ridge shaped detecting rod and detecting wheel, and replace the root fixing device with ridge shaped simulating adjusting device when the peanut, potato and other crops completely buried in the soil are dug. Taking the beet harvest as the research object, the plant spacing, off-centerline distance and forward speed as the experimental factors, and the missed digging rate as the index, the comparative tests between the test bentch and field operation was carried out. The test results showed that the leakage rate of the test bentch is 2.33%-2.72%, and the leakage rate of the field test is 2.38%-2.92%. The test bentch has good excavation accuracy, the absolute deviation rate range is 2.10%-6.85%, the average deviation rate is 3.67%, and the larger the leakage rate is, the larger the deviation rate is. This study can provide reference for the design of automatic alignment digging harvest system of underground crops such as beet, radish, potato, etc. [ABSTRACT FROM AUTHOR]

The ELI-NP (Extreme Light Intensity—Nuclear Physics) project, developed at the Horia Hulubei National Institute for RD in Physics and Nuclear Engineering (IFIN-HH), has included one component dedicated to the study of interactions between brilliant gamma-ray and matter, with applications in nuclear physics and the science of materials. The paper is focused on the interaction chamber, an important part of the facility which hosts the experiment’s samples. The interaction chamber is endowed with a mobile sample support (holder), which automatically tracks the γ-ray beam. The γ-ray radiation source presents a slight variation of the direction of the emitted radiation in time. The built system ensures the permanent collimation between the γ-ray beam and the sample that is being investigated. This is done with two electric motors, which have a symmetrical movement with respect to the center of a rectangle. The specific measures taken by the design and implementation that permit to reach performances of tracking system are emphasized in the paper. The methodology considers the relative displacement between the detectors with which the laboratory is equipped and the absolute position in space of the sample boundary. The control of this motion is designed to respect the symmetry of the system. Both facets of the project (hardware and software) are detailed, emphasizing the way in which the designers ensured compliance with the system of real-time operation conditions of the tracking and monitoring system.

Featured Application: Printing machines, Roller conveyors, Cleanroom applications. Magnetic bearings support rotors in a non-contact way using magnetic force. Therefore, there is no friction and it is possible to measure and control the position of a rotor in the air gap. In this study, the rotational vibration of a roller was minimized using magnetic bearings, and a precision roller capable of automatic alignment using the position control function of magnetic bearings was proposed. A rotation accuracy of approximately 4.6 μm (peak-to-peak) was observed, even under a rotation of 30 rev/min and a radial force load of 300 N. The rotor position control experiment for magnetic bearings showed that 1-μm resolution position control is possible. To further improve the accuracy, the automatic alignment algorithm was proposed using magnetic bearings for the roller misalignment condition, and it was confirmed that alignment is possible at a level that the pressing force difference between both ends of the roller is within 0.3 N. Through this study, it was confirmed that rollers with magnetic bearings can be applied to precision equipment. It is expected that the implementation of the automatic alignment function will simplify the equipment configuration and maintenance compared to conventional rollers with ball bearings. [ABSTRACT FROM AUTHOR]

A collimation system is installed in the Large Hadron Collider to protect its super-conducting magnets and sensitive equipment from potentially dangerous beam halo particles. The collimator settings are determined following an alignment procedure, whereby collimator jaws are moved towards the beam until a suitable spike pattern, consisting of a sharp rise followed by a slow decay, is observed in nearby beam loss monitors. This indicates the collimator jaw is aligned to the beam. The current method for aligning collimators is semi-automated whereby an operator must continuously observe the loss signals to determine whether the jaw has touched the beam, or if some other perturbation in the beam caused the losses. The human element in this procedure can result in errors and is a major bottleneck in automating and speeding up the alignment. This paper proposes to automate the human task of spike detection by using machine learning. A data set was formed from previous alignment campaigns, from which fourteen manually engineered features were extracted and six machine learning models were trained, analysed in-depth and thoroughly tested. The suitability of using machine learning in LHC operation was confirmed during collimator alignments performed in 2018, which significantly benefited from the models trained through machine learning in this study. [ABSTRACT FROM AUTHOR]

For the caused harvesting loss problem by inaccurate alignment of the semi-feeding peanut harvester, an automatic alignment system on the control core of the single chip microcomputer μPD78F0525 was designed. The system adopts a four-bar detection mechanism to transmit the offset to the controller through the sensor and to adjust the excavator in time. On this basis, a peanut automatic alignment test device is developed, which is composed of conveying platform, ridge ditch, hydraulic execution system, signal detection mechanism, signal processing and control system, etc. The influence effect of the main factors of the system is tested through the test bench. The results show: the reaction time increases with the increase of spring preload and deviation distance, gradually decreases and tends to remain unchanged with the increase of forward speed, and first decreases and then increases with the increase of hydraulic flow. The unqualified rate first decreases and then increases with the increase of spring preload, gradually increases with the increase of forward speed and deviation distance, and gradually decreases with the increase of hydraulic flow. The effectiveness and stability of the automatic alignment system can meet the operation requirements. It effectively solved the problem of automatic alignment of the semi-feeding peanut harvester and provided a technical reference for the research and development of the automatic alignment system for harvesting the fruits under the soil. [ABSTRACT FROM AUTHOR]

Non-contact optical detection of ultrasound critically depends on the amount of light collected from the detection surface. Although it can be optimized in multiple ways for an ideal flat polished surface, industrial non-destructive testing and evaluation (NDT&E) usually requires optical detectors to be robust for unpolished material surfaces that are usually rough and curved. Confocal detectors provide the best light collection but must trade off sensitivity with depth of field. Specifically, detection efficiency increases with the numerical aperture (NA) of the detector, but the depth of field drops. Therefore, fast realignment of the detector focal point is critical for in-field applications. Here, we propose an optical distance and angle correction system (DACS) and demonstrate it in a kHz-rate laser-ultrasound inspection system. It incorporates a Sagnac interferometer on receive for the fast scanning of aircraft composites, which minimizes the required initial alignment. We show that DACS performs stably for different composite surfaces while providing ±2° angular and ±2 mm axial automatic correction with a maximum 100 ms realignment time.

X‐ray computed tomography (CT) is an imaging technique intended to obtain the internal structure and three‐dimensional representation of a sample. In general, parallel‐beam CT reconstruction algorithms require a precise angular alignment and knowledge of the exact axis of rotation position. Highly brilliant X‐ray sources with ever‐increasing data‐acquisition rates demand optimized alignment techniques to avoid compromising in situ data analysis. This paper presents a method to automatically align the angular orientation and linear position of the rotation axis in a tomography setup, correlating image features from different X‐ray projections. A method to automatically align the angular orientation and linear position of the rotation axis in a tomography setup that correlates image features from different X‐ray projections is presented. [ABSTRACT FROM AUTHOR]

This paper proposes a novel alignment system based on the measurement of optical path using a light beam scanning mode in a transmissometer. The system controls both the probe beam and the receiving field of view while scanning in two vertical directions. The system then calculates the azimuth angle of the transmitter and the receiver to determine the precise alignment of the optical path. Experiments show that this method can determine the alignment angles in less than 10 min with errors smaller than 66 ;rad in the azimuth. This system also features high collimation precision, process automation and simple installation. [ABSTRACT FROM AUTHOR]

In language production research, the latency with which speakers produce a spoken response to a stimulus and the onset and offset times of words in longer utterances are key dependent variables. Measuring these variables automatically often yields partially incorrect results. However, exact measurements through the visual inspection of the recordings are extremely time-consuming. We present AlignTool, an open-source alignment tool that establishes preliminarily the onset and offset times of words and phonemes in spoken utterances using Praat, and subsequently performs a forced alignment of the spoken utterances and their orthographic transcriptions in the automatic speech recognition system MAUS. AlignTool creates a Praat TextGrid file for inspection and manual correction by the user, if necessary. We evaluated AlignTool’s performance with recordings of single-word and four-word utterances as well as semi-spontaneous speech. AlignTool performs well with audio signals with an excellent signal-to-noise ratio, requiring virtually no corrections. For audio signals of lesser quality, AlignTool still is highly functional but its results may require more frequent manual corrections. We also found that audio recordings including long silent intervals tended to pose greater difficulties for AlignTool than recordings filled with speech, which AlignTool analyzed well overall. We expect that by semi-automatizing the temporal analysis of complex utterances, AlignTool will open new avenues in language production research. [ABSTRACT FROM AUTHOR]

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• A system for self-tapping medical bone screw testing is developed based on ASTM F543. • A program for automatically determining the self-tapping time point is proposed. • The automatic axial alignment of a screw with the pilot hole in a test block is ensured. • Precise loading and holding of axial compression force are achieved. • The self-tapping force determined by our system is more accurate and stable. A specialized system for accurate self-tapping medical bone screw testing is developed, fully meeting the requirements of ASTM F543 -A4 (YY/T 1505-2016). The onset of self-tap is identified automatically according to a change in the slope of the torque curve. Precise load control is applied to determine the self-tapping force accurately. A simple mechanical platform is embedded to ensure the automatic axial alignment of a tested screw with the pilot hole in a test block. In addition, comparative experiments are conducted on different self-tapping screws to verify the system's effectiveness. By the automatic identification and alignment method, both torque curves and axial force curves for each screw exhibit significant consistency. The self-tapping time point derived from the torque curve agrees well with the turning point of the axial displacement curve. The determined self-tapping forces' mean values and standard deviations are both small, which are proved to be effective and accurate in the insertion tests. This work contributes to improving the standard test method for accurate determination of the self-tapping performance of medical bone screws. [ABSTRACT FROM AUTHOR]

Magnetic bearings support rotors in a non-contact way using magnetic force. Therefore, there is no friction and it is possible to measure and control the position of a rotor in the air gap. In this study, the rotational vibration of a roller was minimized using magnetic bearings, and a precision roller capable of automatic alignment using the position control function of magnetic bearings was proposed. A rotation accuracy of approximately 4.6 μm (peak-to-peak) was observed, even under a rotation of 30 rev/min and a radial force load of 300 N. The rotor position control experiment for magnetic bearings showed that 1-μm resolution position control is possible. To further improve the accuracy, the automatic alignment algorithm was proposed using magnetic bearings for the roller misalignment condition, and it was confirmed that alignment is possible at a level that the pressing force difference between both ends of the roller is within 0.3 N. Through this study, it was confirmed that rollers with magnetic bearings can be applied to precision equipment. It is expected that the implementation of the automatic alignment function will simplify the equipment configuration and maintenance compared to conventional rollers with ball bearings.

We present the study on multiplexed beams automatic alignment of high efficiency excimer laser. He-Cd laser with the wavelength of 325 nm is selected as the automatic alignment laser at first. And then, the crosshair arrays close to lens array are proposed and designed as the references of near-field and far-field, whereafter array beams are imaged and processed by specific fluorescence imaging system and region segmentation separately. Experiments are carried out in pre-amplifier II with three beams and double passes in excimer laser MOPA system. Results indicate that accuracy of the automatic alignment beam is 0.54% of the diameter of the windows. Meanwhile, the whole process of automatic alignment just takes 40 s, which ensures intelligent and high effective integration of automatic alignment system. [ABSTRACT FROM AUTHOR]