Correct Position Research Articles

Student radiographers’ knowledge and experience of lateral hip X-ray positioning: A survey

IntroductionThe horizontal beam lateral (HBL) position technique for X-ray imaging has been used for nearly a century; however, this can be challenging for the patient and the practitioner, as it potentially compromises patient dignity. This study explores student radiographers' knowledge and experience of lateral hip positions and their impact on diagnostic quality and patient dignity. MethodA cross-sectional mixed-method online survey of undergraduate diagnostic radiography students was completed. Likert scale assessments, rank ordering questions, and free-test qualitative responses were utilised for questions on knowledge and experience of different positioning, ease to obtain, patient dignity, diagnostic quality, and need for repeats. Data analysis included descriptive statistics and cross-tabulation non-parametric analysis against variables of age, gender and year of study. ResultsResponses were received by n = 42/158 students, a response rate of 27%. The HBL position was the most commonly repeated image (76.6%); the qualitative themes included HBL image quality issues and difficulty in the HBL positioning for elderly or frail patients, often in discomfort and pain. Analysis of student responses to perceived patient dignity in positioning identified 73.8% found the HBL undignified, and 85.7% agreed the Clements-Nakayama (CN) position would be more dignified for patients. The diagnostic image quality of the HBL position (64.2%) was compared to the CN alternative axiolateral (66.6%). Comparison of ease of obtaining the correct position for HBL (47.6%) was higher than CN position (28.6%); this could be due to the lack of experience n = 3/42 (7.1%) of this position. ConclusionOverall, student radiographers' experience and knowledge of various lateral hip positions observed in clinical practice was good. The CN position scored high for diagnostic image (66.6%) and dignity for the patient (85.7%), over the often repeated HBL position (76.6%), which scored lower for image quality (64.2%) and dignity (76.6%). Implications for practiceRadiographers should advocate for professional autonomy and explore alternative positioning techniques. Further investigation into the CN position's utilisation, image quality and radiation dose in England is recommended.

Reliable measurement selection mechanism-based tightly coupled inertial/bionic polarization integration with position correction

Tightly coupled SINS/BPNS (strapdown inertial navigation system/bionic polarization navigation system) integration has been proven to be a promising navigation tactic to substitute SINS/GNSS (global navigation satellite system) integration in GNSS-denied environments. However, the existing tightly coupled SINS/BPNS integrations lack SINS position correction and the reliable screening of BPNS measurements, leading to difficulty to complete navigation tasks. This paper presents an enhanced tightly coupled SINS/BPNS integration to correct both SINS position and attitude and conduct reliable measurement screening for BPNS. This method establishes a new measurement model by formulating the relationship between the SINS position error and angle of E-vector to effectively correct the SINS position. Based on the corrected SINS position, the solar position is calculated and further plugged in the measurement model, leading to improved accuracy. Further, based on the focal plane polarization camera, a mechanism of reliable measurement selection with two-level processing is developed and combined with the extended Kalman filter to improve the filtering robustness for tightly coupled SINS/BPNS integration. Results of simulations and experiments show that the proposed method not only can effectively correct SINS navigation information, but also can possess a strong robustness to exclude unreliable BPNS measurements, leading to enhanced navigation performance for tightly coupled SINS/BPNS integration.

Computer Vision for Assessing Surgical Movements in Neurosurgery.

Objective evaluation of microsurgical technique quality is vital for successful training in neurosurgery. This study aimed to assess the accuracy of automatically detecting a neurosurgeon's proper posture and hand positioning using computer vision. We employed the RTMPose neural network model to identify key anatomical points in the neurosurgeon's projection and calculated various angles formed by connecting these points. By utilizing machine learning on these angles, we were able to classify images of the surgeon's posture and hands into correct positions and various types of errors with an accuracy of at least 0.9. Computer vision enables successful detection and objective assessment of the neurosurgeon's posture and hand positions. The high accuracy of this detection can pave the way for a new training approach in neurosurgery.

An Integrated Navigation Method Aided by Position Correction Model and Velocity Model for AUVs.

When autonomous underwater vehicles (AUVs) perform underwater tasks, the absence of GPS position assistance can lead to a decrease in the accuracy of traditional navigation systems, such as the extended Kalman filter (EKF), due to the accumulation of errors. To enhance the navigation accuracy of AUVs in the absence of position assistance, this paper proposes an innovative navigation method that integrates a position correction model and a velocity model. Specifically, a velocity model is developed using a dynamic model and the Optimal Pruning Extreme Learning Machine (OP-ELM) method. This velocity model is trained online to provide velocity outputs during the intervals when the Doppler Velocity Log (DVL) is not updating, ensuring more consistent and reliable velocity estimation. Additionally, a position correction model (PCM) is constructed, based on a hybrid gated recurrent neural network (HGRNN). This model is specifically designed to correct the AUV's navigation position when GPS data are unavailable underwater. The HGRNN utilizes historical navigation data and patterns learned during training to predict and adjust the AUV's estimated position, thereby reducing the drift caused by the lack of real-time position updates. Experimental results demonstrate that the proposed VM-PCM-EKF algorithm can significantly improve the positioning accuracy of the navigation system, with a maximum accuracy improvement of 87.2% compared to conventional EKF algorithms. This method not only improves the reliability and accuracy of AUV missions but also opens up new possibilities for more complex and extended underwater operations.

Artificial intelligence facilitates the potential of simulator training: An innovative laparoscopic surgical skill validation system using artificial intelligence technology.

The development of innovative solutions, such as simulator training and artificial intelligence (AI)-powered tutoring systems, has significantly changed surgical trainees' environments to receive the intraoperative instruction necessary for skill acquisition. In this study, we developed a new objective assessment system using AI for forceps manipulation in a surgical training simulator. Laparoscopic exercises were recorded using an iPad®, which provided top and side views. Top-view movies were used for AI learning of forceps trajectory. Side-view movies were used as supplementary information to assess the situation. We used an AI-based posture estimation method, DeepLabCut (DLC), to recognize and positionally measure the forceps in the operating field. Tracking accuracy was quantitatively evaluated by calculating the pixel differences between the annotation points and the points predicted by the AI model. Tracking stability at specified key points was verified to assess the AI model. We selected a random sample to evaluate tracking accuracy quantitatively. This sample comprised 5% of the frames not used for AI training from the complete set of video frames. We compared the AI detection positions and correct positions and found an average pixel discrepancy of 9.2. The qualitative evaluation of the tracking stability was good at the forceps hinge; however, forceps tip tracking was unstable during rotation. The AI-based forceps tracking system can visualize and evaluate laparoscopic surgical skills. Improvements in the proposed system and AI self-learning are expected to enable it to distinguish the techniques of expert and novice surgeons accurately. This system is a useful tool for surgeon training and assessment.

Multi-Unmanned Aerial Vehicles Cooperative Trajectory Optimization in the Approaching Stage Based on the Attitude Correction Algorithm

This study investigated the problem of multi-UAVs cooperative trajectory optimization for remote maritime targets in the approach phase. First, based on the precise location information of the cooperative target, a real-time algorithm for correcting UAV attitude angles is proposed to reduce the impact of UAV attitude angle errors and observation system errors on target positioning accuracy. Then, the attitude correction algorithm is integrated into the interacting multiple model-cubature information filter (IMM-CIF) algorithm to achieve the fusion of multi-UAVs observation information. Furthermore, an improved receding horizon optimization (RHO) method is employed to plan the cooperative observation trajectories for UAVs in real time at the target approaching stage. Finally, numerical simulations are conducted to examine the proposed attitude correction and trajectory optimization algorithm, verifying the effectiveness of the proposed method and enhancing the tracking accuracy of the remote target.

An efficient protocol for commissioning radiophotoluminescence dosimeters for radiotherapy dosimetry audits

PurposeThe aim of this study was to develop an efficient protocol for the commissioning of 1000 radiophotoluminescence dosimeters (RPLDs) for use in postal dosimetry audits in radiotherapy. This involved the determination of correction factors necessary to reduce measurement uncertainty and ensure accurate dose measurements. MethodsThe commissioning process started with the RPLDs subjected to a series of controlled irradiations to determine their individual nominal response. Experiments were also conducted to assess the influence of irradiation position, reading position, and ambient temperature on the dosimeter readings all which were accounted for calculating individual sensitivity correction factors (SCFs) for each dosimeter. Statistical analysis was performed to evaluate the variability of SCFs depending on normalization group. An additional investigation simulating different dosimetry audit batches was conducted to study the effect of SCF variability on dosimetry audit measurements. ResultsThe adopted commissioning protocol required irradiation position correction factors (0.990–0.996), readout tray position correction factors (0.992–1.01) and room temperature corrections (∼0.4 % per ° C). This enabled the calculation of SCFs for a batch of 1000 RPLDs and the analysis found the majority of SCFs falling within the range of 0.985–1.015. The standard deviations of the SCF distributions were approximately 1% for all normalization groups. It was observed that SCFs normalized to the entire batch of 1000 dosimeters could be effectively used for smaller audit batches, with an additional uncertainty contribution of up to 0.2%. This minimal increase in uncertainty is acceptable within the context of dosimetry audits. ConclusionsThe developed protocol for commissioning RPLDs provides a reliable method for ensuring accurate dose measurements in postal radiotherapy dosimetry audits. The correction factors applied during the commissioning process were thoroughly described to effectively minimize measurement uncertainty. The findings support the use of SCFs normalized to large dosimeter batches for smaller audit groups, thereby streamlining the dosimetry audit process. Future research should focus on the long-term stability of SCFs to further enhance the reliability of RPLD-based dosimetry audits.

Verification of Nasogastric Tube Positioning Using Ultrasound by an Intensive Care Nurse: A Pilot Study.

Placing a nasogastric tube (NGT) is a frequent nursing technique in intensive care units. The gold standard for its correct positioning is the chest X-ray due to its high sensitivity, but it represents a radiation source for critically ill patients. Our study aims to analyze whether the ultrasound performed by an intensive care nurse is a valid method to verify the NGT's correct positioning and to evaluate the degree of interobserver agreement between this nurse and an intensive care physician in the NGT visualization using ultrasound. Its correct positioning was verified by direct visualization of the tube in the stomach and indirect visualization by injecting fluid and air through the tube ("dynamic fogging" technique). A total of 23 critically ill patients participated in the study. A sensitivity of 35% was achieved using direct visualization, increasing up to 85% using indirect visualization. The degree of interobserver agreement was 0.88. Therefore, the indirect visualization of the NGT by an intensive care nurse using ultrasound could be a valid method to check its positioning. However, the low sensitivity obtained by direct visualization suggests the need for further training of intensive care nurses in ultrasonography. According to the excellent degree of agreement obtained, ultrasound could be performed by both professionals.

Epley Maneuver Skills in Primary Care: 3D Semicircular Canal Models for Self-Learning.

Posterior canal-type benign paroxysmal positional vertigo (BPPV) is commonly treated using the Epley maneuver; however, the maneuver's use in primary care is limited by insufficient expertise. Therefore, this study aimed to evaluate the efficacy of a three-dimensional (3D) semicircular canal model as a self-learning tool for primary care physicians to improve their Epley maneuver technique. Thirty-one participants (18 family physicians, seven residents, and six medical students) performed the Dix-Hallpike maneuver on a nursing manikin, followed by the Epley maneuver on the covered 3D models before and after a 5-minute self-study period with the uncovered 3D model. We measured the number of moved beads from posterior canal into the utricle of the 3D model, time spent on the Epley maneuver, and head suspension angle of the Dix-Hallpike maneuver. Preintervention performance was divided into a skilled group (n=7) that could move almost all the beads and an unskilled group (n=24) that could move a few beads. Postintervention, the unskilled group members significantly improved their skill: The average moved beads increased from 0.35 to 8.00, maneuver time from 26.1 to 35.8 seconds, and head suspension angle from 10.3° to 16.4°. Most participants recognized the importance of correct positioning and spent adequate time. The 3D model was effective as a self-learning tool for improving Epley maneuver performance, particularly for less experienced practitioners. This approach could bridge the gap between evidence and practice in primary care for BPPV treatment, enhancing patient outcomes and reducing the need for specialist referrals.

Diagnostic accuracy of airway ultrasound in confirming the endotracheal tube depth in critically ill children

BackgroundChest X-ray, the established standard of confirming endotracheal tube (ETT) position, has important drawbacks including radiation exposure. Point-of-care airway ultrasound, which has been insufficiently studied in children, can overcome these problems. Materials and methodsThis was a prospective cross-sectional study done on children aged 2 months to 17 years undergoing intubation with cuffed ETT in the PICU. The ETT cuff was filled with saline and three ultrasonographic techniques were used– 1) Suprasternal (SS) method 2) Cricoid (CC) metho and 3) Tracheal ring (TR) method. Position of the ETT as determined by ultrasound and X-ray were compared. The main outcomes were sensitivity, specificity, and area under curve (AUC) for ultrasound-based methods vs. X-ray. For the TR method, concordance between the X-ray and ultrasound categories were taken. ResultsTotal 62 patients were enrolled. The sensitivity and specificity of SS method were 71% (95% CI: 57–83%) and 100% (40–100%). The CC distance method had an AUC of 0.94 (95% CI: 0.86, 1.0). In the TR method, 98% of correct position on X-ray were correctly classified by USG. The agreement between X-ray and ultrasound categories with the cuff between the first and third tracheal rings, was very good [kappa (95% CI): 0.87 (0.70, 1.00), p ≤0.001)]. ConclusionBedside ultrasound is a good method to confirm ETT depth in children. The tracheal ring method had the best diagnostic accuracy and is easy to perform. The new method using cricoid cuff distance needs further validation in different ICU settings.

Response of semicircular canyons and movable cylindrical cavities to SH waves in anisotropic half-space geology

The development of tunnels or the laying of underground pipelines are essential engineering projects in modern society, and in canyon tunnels and underground pipeline projects, the surface motion and cavity edge motion have been topics of concern in ground vibration problems. We investigate the wave scattering problem in an elastic half-space anisotropic medium containing a semicircular canyon and a subsurface movable cylindrical cavity by using the wave function expansion method, the complex function method, and the mirror method. By deriving the governing equation and transforming it into the standard form of the Helmholtz equation satisfying the zero-stress boundary condition, we solve the corresponding displacement functions. Introducing a position correction coefficient, the scattered wavefield in a half-space anisotropic medium is constructed by the mirror method, which improves the problem of scattered wave source singularity in anisotropic half-space media. Then, combining the free boundary conditions with a Fourier series expansion method, we solve the unknown coefficients in the equations. The correctness of the method is verified by degenerating it to a classical analytic solution. Finally, using frequency- and time-domain analysis, we investigate the effects of the relevant parameters on the surface motion [Formula: see text], the dynamic stress concentration factor, and the displacement amplitude [Formula: see text]. The results indicate that rock anisotropy and the presence of semicircular canyons have a significant effect on the dynamic response of subsurface structures. This not only provides a theoretical basis for practical unlined tunnels or pipeline projects but also can provide a basis for seismic design of underground structures.

Влияние позы на эффективность мочеиспускания у мальчика с дисфункциональным мочеиспусканием

Dysfunctional voiding in children without organic pathology of the spinal cord in childhood is now becoming more common. Unproductive voiding with the presence of residual voiding of more than 30% of the functional bladder volume for a long time leads to inflammatory diseases of the lower urinary tract. The physiological process of emptying the bladder requires a certain concentration of the child's attention, controlled activation of voiding reflexes and correct body position, especially for boys. Dysfunctional voiding is often formed in physiologically healthy boys with systematic emptying of the bladder in a sitting position, which disrupts the natural configuration of the pelvic floor muscles. Article represents a clinical case of a child with recurrent urinary infection and ineffective urination at the age of 12 y/o, whose treatment was based on training pelvic reflexes and voiding in a standing position, which in its turn had allowed normalization of the miction parameters and stopped the recurrent low urinary tract infection.

Manufacture of the Invar Film Using a Continuous Electrodeposition Technique for the OLED FMM

In the manufacturing processes of red-green-blue (RGB)-type organic light emitting diode (OLED) displays, Invar is used as a material for the fine metal mask (FMM), which guides the evaporated diode materials through its small holes onto the correct positions of the substrate glass. The electroforming of Invar is an immediate hot issue in the RGB-type OLED display industries. Contrary to the conventional top-down method of pyrometallurgically producing Invar, a bottom-up approach of electroforming is a promising technology for producing very thin FMMs to achieve high-quality images in such displays. The present authors have recently presented that the electroformed Invar via sophisticated heat treatment exhibits the coefficient of thermal expansion (CTE) as low as that of the conventional Invar. The current work has been aimed at investigating the effect of the microstructure evolution on the CTE during heat treatment of the electroformed Invar. Finally, we propose optimal process conditions to manufacture the Invar FMM applied for an ultra high definition (UHD) grade of the OLED display.

Experience in the use of circular incision bi-pedicled vertical flap based mastectomy for grade III gynecomastia: A case series

Introduction and importanceSurgical management of grade III gynecomastia with excess redundant skin is challenging. The choice of the surgical technique is mainly decided upon the size of the gynecomastia, the skin redundancy and correction of nipple position. Case presentationWe report our experience in the use of the circular incision bi-pedicled vertical flap based mastectomy for grade III gynecomastia according to Simon classification. This is a retrospective study conducted between January 2022 and April 2023 at two selected units in Sri Lanka. Clinical discussionA total of 7 patients with bilateral grade III gynecomastia were included in this study with a median age of 24 years (range: 18–42 years). The mean BMI was 23.2 kg/m2. All patients exhibited near symmetrical breasts and large areolar diameters. All patients complained of physical and psychological dissatisfaction with their condition and sought an aesthetic correction. Two patients were diagnosed with Klinefelter syndrome and others were apparently healthy. The main complication was seroma formation (7/7). No patients developed haematoma. Nipple hypothesia was noted in two patients which improved on follow up. The mean follow- up duration was 4–9 months. The survey of patient satisfaction showed 9 for contour, 8.6 for wound scars, 9.2 for overall satisfaction and 9.6 for improvement in self-confidence. ConclusionThe above surgical technique achieved satisfactory aesthetic results while avoiding unsightly scars or serious complications and can be considered in the surgical decision making for grade III gynecomastia.

A Case Study of Suspected Childhood Apraxia of Sign.

We provide a case report of "Zoe," a 4-year-old deaf child from a deaf signing family, who presented with a possible case of Childhood Apraxia of Sign (CASign). The description is based on reports from the child's speech-language pathologist, her Individualized Education Program report, and a clinician-created sign imitation task. Zoe's sign articulation errors in American Sign Language differed from those reported for typically developing deaf children and were parallel to the types of errors observed for hearing children with childhood apraxia of speech. Specifically, Zoe produced inconsistent errors across signs, substituted more complex handshapes for simple handshapes, made errors on both unmarked (common) and marked (less common) forms, produced articulatory distortions (rather than substitutions), and exhibited "groping" behaviors (a sequence of attempts to move her hands into the correct position). In addition, Zoe sometimes self-corrected her errors by manipulating her own hands, for example, using her left hand to move the thumb of her right hand into the correct position. Zoe's pattern of sign errors is consistent with an underlying deficit in motor planning and/or programming and may constitute the first reported case of CASign.

Intraoperative OCT to check the correct postimplant position of PreserfloTM.

This study was designed to examine the capacity of intraoperative optical coherence tomography (OCT) to predict the postimplant position of the glaucoma drainage device PreserfloTM. 13 eyes (mean age 65.42 (14.89) years) underwent PreserfloTM (Santen, Osaka, Japan) placement. Before surgery, participants were subjected to a comprehensive ophthalmic examination (intraocular pressure (IOP), cup to disk ratio (C/D), visual field, OCT, endothelial cell count). Anterior segment OCT scans were obtained intraoperatively using a Rescan 700 OCT system (Carl Zeiss Meditec, Inc., Oberkochen, Germany). One day postsurgery, anterior segment OCT using the Spectralis OCT (Heidelberg Engineering GmbH) was performed in a sitting position to capture the same chamber cross-section as before. The main outcome variables were tube-endothelium distance (T-E) and tube length (TL) in the anterior chamber measured using both OCT systems. Correlation between intraoperative and office measurements was examined through Pearson correlation (r) and intraclass correlation coefficients (ICC). Mean intraoperative and in-office T-E were 625.26 (SD 366.60) versus 561.16 (SD 364.62) µm respectively (p = 0.540). Intraoperative and in-office anterior chamber TL were 1386 (SD 701.82) and 1433.91 (SD 713.55) µm, respectively (p = 0.029). Excellent correlation was observed between both sets of T-E (r = 0.992; p = 0.008) and TL (r = 0.984; p = 0.016) values. Both OCT systems showed good agreement yielding ICCs of 0.992 (p < 0.001) for T-E and 0.995 (p = 0.001) for TL. Excellent correlation was observed between our intraoperative and postoperative OCT measurements. These results support the usefulness of intraoperative OCT to confirm the correct position of an implanted PreserfloTM microshunt.

Cervical vertigo due to rotational fixation of atlantoaxial joint combined with benign paroxysmal positional vertigo: A case report and literature review.

Vertigo is the most common clinical complaint, misdiagnosed patients are not rare, so it is very important to exclude and identify vertigo. For vertigo caused by multiple causes, including cervical vertigo with atlantoaxial rotation fixation combined with benign paroxysmal positional vertigo (BPPV), tuina can correct joint misalignment. The reduction technique will return the fallen otolith to the correct position. The use of massage and reduction can improve clinical symptoms and improve quality of life and may be a simple, safe, and effective treatment strategy for this disease. We report on a patient with both cervical vertigo due to atlantoaxial rotational fixation and BPPV, including his imaging examination, clinical manifestations, and treatment methods. Cervical vertigo (atlantoaxial rotatory fixation) and BPPV. Tuina combined with atlantoaxial directional inverted reduction technique and reduction manipulation. The patient's vertigo symptoms improved significantly, nystagmus disappeared, cervical occipital pain, nausea, head distension, and other symptoms disappeared, and cervical motion rotation reached 60°. This study proved the effectiveness of massage combined with a reduction in the treatment of cervical vertigo and BPPV, as well as the importance of vertigo diagnosis and differential diagnosis, and provided a new treatment idea for the future diagnosis and treatment of vertigo caused by a variety of causes.

Reduction of post-radiotherapy urinary toxicity via intrafractional MV-kV prostate location monitoring

We hypothesized that an in-house developed system using MV and kV image guidance (MKIG) to ensure correct prostate positioning during SBRT could potentially avoid unwanted doses to non-target tissues, leading to reduced toxicities. We built a 3D MKIG platform that accurately tracks prostate implanted fiducials in real-time and clinically translated the system to replace a commercial approach, intrafraction motion review (IMR), which only tracks fiducials in the 2D kV views. From 2017 to 2019, 150 prostate cancer patients were treated with SBRT and monitored by MKIG. The motion trace of the fiducials alerts therapists to interrupt and reposition the prostate when displacement exceeds a 1.5 mm threshold. A comparison cohort of 121 patients was treated with the same dose regimen and treatment technique but managed by IMR. Statistics of intrafractional patient shifts and delivery time were collected to evaluate the workflow efficacy. The incidence of grade ≥2 urinary toxicities was analyzed to assess clinical complications. The median follow-up time was 3.7 years (0.2 to 8.2 years). MKIG treatments had more treatment shifts (1.09 vs. 0.28) and a longer average delivery time per fraction (579±205s vs. 357±117s) than IMR treatments. Three-quarters (75%) of shifts resulting from MKIG were ≤3mm, vs. 51% in IMR, indicating that MKIG detected and corrected smaller deviations. The incidence of grade ≥2 urinary toxicity was lower in the MKIG than IMR cohort: 10.7% vs. 19.8% (p=0.047). On multivariate analysis of late urinary toxicity, only high (>7) pre-RT IPSS (p<0.043) and the use of MKIG were selected (p< 0.029). Automated and quantitative MKIG introduced minimal workflow impact and was superior to IMR in localizing the prostate during SBRT, which correlated with a clinically significant reduction in late urinary toxicity. Further clinical testing via randomized trial will be required to validate the impact on outcomes.

Effect of posture on position of subcutaneous implantable cardioverter-defibrillator

BackgroundThe PRAETORIAN score was developed as an alternative for defibrillation testing after subcutaneous implantable cardioverter-defibrillator implantation to assess 3 aspects of implant position on a bidirectional chest radiograph. The score is validated on a standard standing chest radiograph with arms elevated in the lateral view. ObjectiveWe aimed to evaluate the effect of different anatomic positions on the PRAETORIAN score. MethodsThirty patients with a subcutaneous implantable cardioverter-defibrillator underwent standard posterior-anterior and lateral chest radiography, including additional lateral views in 2 positions: standing with arms down and supine with arms alongside the body. PRAETORIAN score and weighted κ coefficient were calculated for each position. ResultsIn 8 of 30 patients, the PRAETORIAN score was ≥90 in standard position. The agreement in PRAETORIAN score was substantial (κ = 0.677) for the position with the arms down and fair (κ = 0.399) for the supine position. With the arms down, the PRAETORIAN score decreased in 10 patients (33%), 4 of whom changed to a lower risk category. In supine position, the PRAETORIAN score decreased in 16 patients (53%), 7 of whom changed to a lower risk category, 1 from high to low risk. ConclusionA supine or arms-down position during chest radiography can result in lower PRAETORIAN scores and underestimation of associated risk on defibrillation testing failure. This emphasizes the importance of correct anatomic positioning (arms up) during chest radiography when the PRAETORIAN score is used.

Monitoring Welding Torch Position and Posture Using Reversed Electrode Images – Part II, Experimental and Analysis for the REI-TPA Model

This paper is a sequel to the previous paper. In the previous research (Ref. 1), a REI-TPA model was established to quantitively relate reversed electrode images (REIs) to welding torch position and attitude (TPA). In this research, the REI-TPA model was validated with bead-on-plate welding experiments on S304 stainless steel plates. The contours of the REI and electrode as well as the weld pool geometry were extracted from the image with a developed, robust algorithm, and the arc length was calculated with welding voltage. The offset distance and deflection angle of the welding torch relative to the correct position and attitude were calculated by inputting the extracted parameters into the REI-TPA model. The computational result was compared to the experimental data. The result showed that the model is correct and the monitoring of the welding torch with the REI-TPA model is available. The REITPA model can be applied to real-time control of TPA, which is a supplement to the application of the weld passive visual image and an extension of multiinformation acquisition and processing methods in the welding process.