Position Of Device Research Articles

Prognostic significance of right ventricle to pulmonary artery coupling acute improvement after mitral transcatheter edge-to-edge repair

Abstract Background Transcatheter Edge-to-Edge Repair (TEER) of mitral valve is a valid treatment option for severe mitral regurgitation. The right ventricle is acutely affected by early hemodynamic changes following the correction of significant mitral regurgitation. Echocardiographic parameters of the right chambers could have a prognostic impact even in a periprocedural setting. In particular, right ventricle to pulmonary artery coupling improvement may be of pivotal importance, as this parameter is a validated marker of right ventricle function. Purpose To evaluate the prognostic impact of early improvement of right ventricle to pulmonary artery coupling assessed by means of the Tricuspid Annular Plane Systolic Excursion/Pulmonary Artery Systolic Pressure (TAPSE/PASP) ratio after TEER. Methods This retrospective single centre study included patients treated with TEER in our hospital from 2015 to 2023. Transthoracic echocardiography was performed before and shortly after device positioning. Acute effects of TEER on echocardiographic parameters were assessed by paired samples t-test. Diagnostic accuracy of the percent variation in the TAPSE/PASP ratio was assessed by means of receiver-operating characteristics analysis. Prognosis was evaluated by Kaplan-Meier analysis. Results The study included 95 patients (age 78 ± 10 years; 63% men; BMI 25 ± 5 kg/m2) with severe or moderate-to-severe mitral regurgitation. Mean baseline Left Ventricle (LV) ejection fraction was 45 ± 16%, LV end-diastolic volume was 157 ± 62 ml and effective regurgitant orifice area was 41 ± 25 mm2. Post-procedural echocardiographic assessment showed early improvement of LV end-diastolic diameter (p < 0.001), LV end-diastolic volume (p = 0.025), LV stroke volume (p < 0.001), LV global longitudinal strain (p < 0.001), right ventricle free wall longitudinal strain (p < 0.001) and PASP (p = 0.002). Percent improvement of TAPSE/PASP ratio showed a sufficient diagnostic accuracy in predicting a composite outcome of hospitalisation for heart failure and all cause mortality at 1 year (area under the curve 0.66, p = 0.047), with an optimal cut-off of 5.5%. An improvement of the TAPSE/PASP ratio over this threshold was associated with a reduction in the composite outcome (hazard ratio 0.38, p = 0.045). Conclusion TEER improves both left and right ventricular dynamics, which can be detected with echocardiography. In particular, an acute improvement of the TAPSE/PASP ratio is associated with an improvement in short-term prognosis. A comprehensive assessment of right ventricular function, including TAPSE/PASP ratio, should be routinely performed before and after TEER.

Spin Texture Engineering by a Temperature Gradient in Ultrathin CoFeB Film

Magnetic texture in a chiral material is touted as one of the next-generation nonvolatile computing elements. Thermal manipulation of magnetic textures attracts considerable attention and has promising applications. Here, the temperature-dependent magnetic properties of Ta/CoFeB/MgO thin film are studied experimentally and theoretically. We report the controllable spin texture distribution with a temperature gradient in the Ta/CoFeB/MgO thin film. The nucleation area could be generated at a certain location through the cooperation of heat and magnetic field. This method offers a way to realize spin texture injection at specific positions in magnetic thin films and devices. This work provides useful guidelines for the thermal control of the spintronic device operation.

Safety profile, electrical performances and clinical outcomes of a novel leadless pacemaker; first results from real-world clinical practice in Saudi Arabia

Abstract Introduction Leadless pacemakers (LP) are emerging as an effective and safe alternative to transvenous pacemakers to reduce lead-related and pocket-related complications and to improve patient experience. A new LP system, the Aveir VR, has been approved in 2022 for US and other countries, and in 2023 for Europe, and features innovative characteristics such as the active fixation helix mechanism and the possibility to measure sensing/pacing parameters before LP deployment. Purpose Evaluate safety, electrical performances and clinical outcomes associated with the first Aveir VR LP implants in 2 Hospitals in Saudi Arabia. Methods We performed a prospective evaluation of all-comer patients who received Aveir VR LP. Decision for LP implant was based on conditions such as cardiac pacing indication, lack of upper extremity venous access, risk of device infection, and life expectancy, and using shared decision-making. Clinical and electrical data were collected at implant and at 1st and 6th month visits. Results A total of 54 patients (25 female, mean age 69 years) were included between December 2022 and October 2023. Pacemaker implant indication was AV block in 25 (46%) patients, sinus node disease in 19 (35%) patients, atrial fibrillation and slow ventricular response in 9 (17%) patients and left bundle branch block in 1 (2%) patient. Implant was successful in all attempted cases. Final device position was lower septum in 51/54 (94.4%) patients and mid-septum in 3/54 (5.6%) patients. Mean procedure time was 48±22 minutes and showed a decreasing trend as a function of operator experience with a mean of 55, 50 and 36 minutes in the first, second and third group of consecutive implants, respectively. Mean fluoroscopic time was 11±8 minutes and showed a decreasing trend as a function of operator experience with a mean of 13, 13 and 6 minutes in the first, second and third group of consecutive implants, respectively. Final device position was achieved at first attempt in 42/54 (77.8%) cases and at first or second attempt in 51/54 (94.4%) cases. At implant mean R wave sensing was 7.6±3.7 mV, mean impedance was 724±335 Ohm, mean threshold was 1.0±0.6 V at 0.4 ms. During implant there was one patient with pericardial effusion treated with pericardiocentesis. In a mean follow-up of 73 days there were no procedure-related or device-related complications, electrical parameters showed acceptable values, and all implanted devices performed as expected. Median longevity, estimated at last follow-up visit, was 19 years (interquartile range: 12-20 years). Conclusion First real-world cases of use of a novel leadless pacemaker in Saudi Arabia show optimal feasibility and good safety profile and electrical performances. Procedure and fluoroscopic times were acceptable and decreased as a function of operator experience. Longevity estimations predict very long service life-times.

Minimum data sampling requirements for accurate detection of terrain-induced gait alterations change with mobile sensor position

Human gait is a key biomarker for health, independence and quality of life. Advances in wearable inertial sensor technologies have paved the way for out-of-the-lab human gait analysis, which is important for the assessment of mobility and balance in natural environments and has applications in multiple fields from healthcare to urban planning. Automatic recognition of the environment where walking takes place is a prerequisite for successful characterisation of terrain-induced gait alterations. A key question which remains unexplored in the field is how minimum data requirements for high terrain classification accuracy change depending on the sensor placement on the body. To address this question, we evaluate the changes in performance of five canonical machine learning classifiers by varying several data sampling parameters including sampling rate, segment length, and sensor configuration. Our analysis on two independent datasets clearly demonstrate that a single inertial measurement unit is sufficient to recognise terrain-induced gait alterations, accuracy and minimum data requirements vary with the device position on the body, and choosing correct data sampling parameters for each position can improve classification accuracy up to 40% or reduce data size by 16 times. Our findings highlight the need for adaptive data collection and processing algorithms for resource-efficient computing on mobile devices.

Left atrial appendage closure guided by fusion of 3D computational modelling on real-time fluoroscopy: A multicenter experience

BackgroundPatient-specific 3-dimensional (3D) computational modelling offers a tailored approach with promising results, but experience using digital-twin fusion on real-time fluoroscopy to guide left atrial appendage closure (LAAC) is unreported. ObjectivesTo assess whether LAAC guided by fusion of a 3D computational model on real-time fluoroscopy is safe and effective. MethodsWe included retrospectively through a multicenter registry all consecutive patients with non-valvular atrial fibrillation (AF) who underwent LAAC guided by artificial intelligence (AI)-enabled computer simulations (FEops, Gent, Belgium) fusion with real-time fluoroscopy. Operators selected the appropriate device size and position in relation to the LAA using FEops HEARTguide™, and a digital twin was provided for image fusion. The primary efficacy endpoint was successful LAAC with the use of a single device, without moderate or greater peri-device leak and/or device related thrombus (DRT) on follow-up imaging. The primary safety endpoint was a composite of major procedural complications including tamponade, stroke, systemic embolism, major bleeding, and device embolization. ResultsA total of 106 patients underwent LAAC with an Amulet™ or Watchman FLX™ device using CT-model-fluoroscopy fusion imaging. Device implantation was successful in 100 % of cases. The primary efficacy endpoint was met in 82 patients (89 %). A single-device SINGLE-deployment LAAC procedure was observed in 49 cases (46 %). The primary safety endpoint occurred in 2 patients (1.9 %). After a median follow-up of 405 days, two patients suffered an ischemic stroke and four expired. ConclusionsFusion of a CT-based 3D computational model on real-time fluoroscopy is a safe and effective approach that may optimize transcatheter LAAC outcomes.

Application of 3D Printing to Design and Manufacture Pancreatic Duct Stent and Animal Experiments.

Objective: Postoperative pancreatic fistula (POPF) is a common and challenging complication following pancreaticoduodenectomy (PD), occurring in 2% to 46% of cases. Despite various pancreaticojejunostomy techniques, an effective method to prevent POPF has not been established. This study aimed to develop and evaluate a novel 3D-printed biodegradable pancreatic duct stent to simplify the surgical process of pancreaticojejunostomy, reduce anastomotic complexity, and minimize postoperative complications. Methods: Data from 32 patients undergoing total laparoscopic pancreaticoduodenectomy were utilized. Preoperative CT scans were transformed into 3D reconstructions to guide the design and printing of customized stents using polylactic acid (PLA). The stents were assessed for mechanical integrity, surface texture, and thermal stability. Animal experiments were conducted on 16 mini pigs, with the experimental group receiving the novel stent and the control group receiving traditional silicone stents. Results: The 3D-printed stents demonstrated accurate dimensional replication and mechanical reliability. In the animal experiments, the experimental group showed no significant difference in postoperative complications compared to the control group. At 4 weeks post-surgery, CT scans revealed well-healed anastomoses in both groups, with no significant inflammation or other complications. Histological examination and 3D reconstruction models confirmed good healing and device positioning in the experimental group. Conclusion: The 3D-printed biodegradable pancreatic duct stent offers a promising solution for pancreaticojejunostomy, with comparable safety and efficacy to traditional methods. Further research is needed to validate its clinical application.

Patent ductus arteriosus closure in small infants weighing less than 1500 g using KA micro plug: steps and tips.

Transcatheter patent ductus arteriosus closure in premature infants is gaining attention with rapidly growing experience. The KA micro plug device poses many favourable features for ductus arteriosus closure in premature infants. The study aimed to describe the technique and outcomes of a KA micro plug in closing the ductus arteriosus in premature infants weighing less than 1500 g. This is a single-centre retrospective study in premature infants with patent ductus arteriosus weighing less than 1500 g who underwent off-label use of a KA micro plug at the Stead Family Children's Hospital from February 2022 to December 2023. Eighteen premature infants weighing less than 1500 g underwent attempted transcatheter ductus arteriosus closure using a KA micro plug device. Median weight, age, and corrected gestational age at the procedure were 943 g (682-1225), 26 days (9-79), and 28.5 weeks (25.6-32), respectively. The procedure was successful with complete closure achieved in all patients. No major haemodynamic instabilities were encountered. No catheterization-related complications were encountered. On a median follow-up of 10.9 months (0.1-19), all patients are alive with the device in a good position without residual shunt or abnormal findings. KA micro plug device for patent ductus arteriosus in infants weighing less than 1500 g is feasible, safe, and effective. We recommend that manufacturers of devices used to close the ductus arteriosus in small infants enhance both the devices and their delivery systems to simplify the procedure and mitigate the risk of haemodynamic instability.

Urinary Continence Restoration Through an Endourethral Device: A 3-Month Pilot Study on 10 Patients.

Background: Stress urinary incontinence (SUI) is a widespread and frustrating condition that affects millions of people worldwide, with severe consequences on patients' quality of life and health care systems' costs. Currently, the most severe cases of SUI are treated using implanted (and rather invasive) extraurethral artificial sphincters. The authors propose an innovative, minimally invasive endourethral device for the treatment of SUI. Methods: Ten patients with SUI were enrolled in three Italian centers and underwent device implantation. After 10, 30, 60, and 90 days, correct device position was confirmed by ultrasonography. Improvements in continence and quality of life were evaluated through a 24-hour pad-test, an International Consultation on Incontinence Questionnarie-Short Form (ICI-Q) and a custom checklist. The device was explanted after 90 days. Results: The proposed device was successfully implanted and explanted in 8 out of 10 patients. The results of the pad-test, ICI-Q, and custom checklist demonstrated remarkable improvements in continence (median improvement: 82% with respect to the initial condition) and quality of life (mean reduction of the impact of urine losses on the quality of life: 61%). No major pain or discomfort was reported. Conclusions: The results demonstrate the efficacy of the proposed endourethral artificial sphincter in addressing SUI. The proposed device was successfully implanted and explanted in a short time (∼10 minutes) without intrinsic side effects and without triggering pain or discomfort.

Floor-Level Occupancy Estimation of a Multi-Story Building Using Coarse Wi-Fi Data

In recent years, there has been an extraordinary increase in wireless capable devices and network infrastructure, which spawned a corresponding rise in data produced from the interactions of these technologies. Mobile devices constantly roam, leading to a perpetual dialog between a mobile device and wireless access points. This dialogue generates a continuous stream of device-specific data, including but not limited to a device’s media access control address, time of access, and received signal strength. Given the knowledge of the access point’s location and received signal strength, it is possible to infer the position of user devices and estimate their mobility and occupancy. This article presents two methods for accurately measuring floor-level occupancy in a multi-story building at Texas State University using coarse Wi-Fi log data. The first method employs a static filter, while the second incorporates user-role data and user location to create a dynamic filter. Quantitative methods are used to evaluate these filters against field-collected reference data and existing internal people-counting sensors. Our results demonstrate that the dynamic filter, leveraging variable thresholds, provides a more accurate estimation of occupancy compared to the fixed 5-min static filter which consistently overestimated occupancy. This research sheds light on the potential of dynamic filters derived from user-role data for precise floor-level occupancy estimations, with implications for various applications.

A New Scoring System to Evaluate the Position and Functioning of Supraglottic Airway Devices in Research and Clinical Audits.

A New Scoring System to Evaluate the Position and Functioning of Supraglottic Airway Devices in Research and Clinical Audits.

Tissue Oedema Following Pulsed Field Ablation Recognized during a Concomitant Left Atrial Appendage Closure Procedure. A Case Report

Abstract Background In patients with non-valvular atrial fibrillation (AF), at high stroke risk and who are ineligible for long-term oral anticoagulation the left atrial appendage closure (LAAC) could be an alternative to anticoagulation. Pulsed field ablation (PFA) is a new nonthermal method for cardiac ablation modality based on high-voltage electrical energy for irreversible electroporation. We first report a case of a concomitant PFA pulmonary vein isolation and LAAC. Case Summary A 74-year-old female patient was referred to our department for pulmonary vein isolation (PVI) for persistent AF (CHA2DS2-VASc Score 5). A concomitant percutaneous LAAC was proposed because of a history of previous cerebellar transient ischemic attack despite continuous oral anticoagulation therapy. PVI was achieved with a pentaspline PFA catheter, LAAC performed with a WATCHMAN FLXTM device (Boston Scientific, Plymouth, MN, USA). After PVI, a swelling of the left atrial ridge was observed, yet a 27 mm LAAC device was successfully implanted. The follow-up transesophageal echo (TEE) after 6 weeks showed complete resolution of the oedema, no device related thrombus but a slight proximal tilting of the LAAC device without leakage could be observed. The 6-month follow-up demonstrated a stable sinus rhythm, no stroke or bleeding events were recorded. Discussion In this case of synchronous PFA-PVI procedure in AF and Watchman FLXTM device implantation, the electroporation created an acute oedema at the ridge level which at the TEE follow-up after 6 weeks was resolved. This resulted in a slightly tilted Watchman device position which was nevertheless stable and showed no leakage.

Research on Point Cloud Acquisition and Calibration of Deep Hole Inner Surfaces Based on Collimated Ring Laser Beams.

In this study, a ring light point cloud calibration technique based on collimated laser beams is developed, aiming to reduce errors caused by the position and attitude changes of traditional ring light measurement devices. This article details the generation mechanism of the ring beam and the principle of deep hole measurement. It introduces the collimated beam as a reference, building on traditional ring light measurement devices, to achieve the synchronous acquisition of the ring beam and collimated spot images by an industrial camera. The Steger algorithm is employed to accurately extract the coordinates of the point cloud contours of both the ring beam and the collimated spot. By analyzing the shape and position changes of the collimated spot contour, the spatial position and attitude of the measuring device are precisely determined. This technique is applied to the 3D reconstruction of the inner surface of deep holes, ensuring the accurate restoration of the spatial positional attitude of the ring beam by incorporating the spatial positional attitude parameters of the measuring device to precisely calibrate the cross-sectional point cloud coordinates. Experimental results with ring gauges and deep hole workpieces demonstrate that this technique effectively reduces the percentage of point cloud data outside the tolerance range, and improves the accuracy of the 3D reconstruction model by 6.287%, thereby verifying the accuracy and practicality of this technique.

A set of Models for Device Positioning in Sixth Generation Networks. Part 1. Methods Survey and Problem Statement

Relevance. Today, terahertz radio systems are considered as a technological basis for integrating methods and means of radio communication and radar in promising sixth-generation networks. If in 4G LTE networks the capabilities of positioning user equipment using the infrastructure of base stations were considered as auxiliary options, then in 5G NR networks, location determination technologies (LDTs) have become full-fledged services, the requirements for which are specified along with communication services. A new trend in positioning in 5G NR networks, compared to 4G LTE networks, has become a single-position assessment of the coordinates and orientation of the user equipment based on signals from a single base station with the ability to distinguish between direct and reflected signals. 6G networks are still in their infancy, but it can already be stated that they mark the next stage in the evolution of digital ecosystems, which is characterized by the convergence of communication technologies, localization and sensing of radio air and the surrounding space by radio engineering means.Purpose. This work opens a research cycle devoted to the review of models, methods and algorithms for positioning devices in 6G networks. The goal of the cycle is to find and justify new radio engineering means for achieving decimeter accuracy in 6G device coordinate estimates. The first part of the cycle provides an overview of the methods and formalization of the model for collecting primary measurements.Method is an analytical review of the state of the problem based on current scientific publications, conceptual modeling, categorical approach, expert combination, comparative analysis, formalization, mathematical and simulation modeling.Results. As a result of the review of device positioning methods during the transition to 6G networks, key performance indicators and LDT scenarios are updated. As a result of the comparative analysis of 5G and 6G networks, new factors, advantages and disadvantages of positioning technologies during the transition from millimeter wave networks to terahertz networks are systematized. A formalized mathematical model for collecting primary measurements is used in the simulation model for assessing the accuracy of device positioning in the second part of the cycle.Novelty. This cycle is the first such study in the Russian scientific segment on network positioning of the sixth generation of the terahertz range, in which the author's version provides an overview of methods and a systematization of a set of new factors of the OMP in communication networks.The theoretical significance of the review-analysis lies in the establishment of both technological obstacles and new opportunities for increasing positioning accuracy during the transition to 6G networks.The practical significance of the formalized mathematical model lies in its subsequent software implementation for numerical justification of the limits of positioning accuracy in 6G networks.

Optimal Positioning of Load-Distributing Band CPR Device by Body Mass Index.

Background: Research investigating the optimal compression position for load-distributing bands (LDBs) in treating cardiac arrest is limited This study aimed to determine the optimal LDB position based on body mass index (BMI). Methods: A simulation study was conducted using chest and abdominal computed tomography imaging data collected with patients in the arms-down position. Participants were categorized into three BMI groups: low (<18.5 kg/m2), normal (18.5-25 kg/m2), and high (≥25 kg/m2). The assumed compression area was 20 cm below the axilla. The optimal compression position was identified by adjusting the axilla to maximize the thorax-to-abdomen volume ratio (TAR) and the covered heart volume ratio (CHR), defined as the ratio of heart volume compressed by the LDB to total heart volume. Optimal compression positions were compared across BMI groups. Results: Among 117 patients, TAR was significantly lower in the low BMI group compared to the normal and high BMI groups (p < 0.001), while CHR differences were not significant (p = 0.011). The distance between the optimal position and axilla height was significantly greater in the normal and high BMI groups than in the low BMI group (46.5 cm vs. 66.0 cm vs. 72 cm, respectively; p < 0.001). For each unit increase in BMI, the optimal position shifted significantly cephalad relative to axilla height (β coefficient 2.39, adjusted p < 0.001). Conclusions: Significant differences in TAR were observed among BMI groups. As BMI increased, the optimal LDB position shifted progressively cephalad.

Radiofrequency as a method of localizing impalpable breast lesions

BackgroundThe incidence of early stage breast cancer has risen as a result of increased detection of non-palpable tumors through the implementation of screening programs and greater public awareness. Performing breast-conserving surgery can be challenging due to the need for accurate localization of non-palpable breast lesions, particularly given the logistical difficulties associated with wire localization. After implementing a new technique for localizing non-palpable breast lesions (LOCalizerTM Radiofrequency identification TAG-Hologic®), a radiofrequency identification tag localization device manufactured by Hologic, Inc. in Marlborough, MA, was launched in 2017, our objective was to investigate its impact on surgical outcomes, whether there was an increase in re-excision rates for positive margins and whether the attainment of clear margins was dependent on the exact positioning of the RFID device. MethodA single-center single-arm interventional study, data were gathered both in a forward-looking manner for 1 year (prospectively) and by looking back at past records for 1 year (retrospectively) for a total period of two years. Individuals who were diagnosed with non-palpable breast lesions, as confirmed by histological analysis, or invasive breast cancer and who were scheduled to undergo breast-conserving surgery were eligible for inclusion in the study. The RFID (Radiofrequency Identification) method was used to localize the lesions prior to surgery. Either with a mammogram or ultrasound scan position of the Tag was recorded, including the distance of the lesion from the center of the lesion and the lesion depth from the skin in millimeters. The rate of re-excision was documented and examined in relation to the parameters mentioned above. ResultsTwo hundred and twenty RFID Tags were inserted in two hundred and seventeen (three patient had bilateral tags insertion), patients aged between 30 and 85 had a localizer Tag inserted between Oct 2020 and Oct 2022. Three patients had non-palpable breast lesions in both breasts. Fourteen were inserted under stereotactic guidance and two hundred and six under ultrasound guidance. Ten patients subsequently had wire insertion also due to Tag position. Of 210 procedures, RFIF Tags within the lesion was seen in hundred and sixty patients (76.19 %). An additional 50 procedures were performed using the RFID Tag system, which were not directly related to the lesion but were deemed appropriate to proceed with.Out of a total of 220 procedures, positive margins were observed in 38 cases (17.27 %). Among these cases, eleven (28.94 %) involved the use of the RFID Tag system, not within the lesion but adjacent to it (within 15 mm surrounding the lesion). ConclusionRFID is a good alternative to wire localization of non-palpable breast lesions. Re-excision rates are higher in patients with Tag outside the lesion compared to those with Tag within the lesion.

Real-Time Indoor Visible Light Positioning (VLP) Using Long Short Term Memory Neural Network (LSTM-NN) with Principal Component Analysis (PCA).

New applications such as augmented reality/virtual reality (AR/VR), Internet-of-Things (IOT), autonomous mobile robot (AMR) services, etc., require high reliability and high accuracy real-time positioning and tracking of persons and devices in indoor areas. Among the different visible-light-positioning (VLP) schemes, such as proximity, time-of-arrival (TOA), time-difference-of-arrival (TDOA), angle-of-arrival (AOA), and received-signal-strength (RSS), the RSS scheme is relatively easy to implement. Among these VLP methods, the RSS method is simple and efficient. As the received optical power has an inverse relationship with the distance between the LED transmitter (Tx) and the photodiode (PD) receiver (Rx), position information can be estimated by studying the received optical power from different Txs. In this work, we propose and experimentally demonstrate a real-time VLP system utilizing long short-term memory neural network (LSTM-NN) with principal component analysis (PCA) to mitigate high positioning error, particularly at the positioning unit cell boundaries. Experimental results show that in a positioning unit cell of 100 × 100 × 250 cm3, the average positioning error is 5.912 cm when using LSTM-NN only. By utilizing the PCA, we can observe that the positioning accuracy can be significantly enhanced to 1.806 cm, particularly at the unit cell boundaries and cell corners, showing a positioning error reduction of 69.45%. In the cumulative distribution function (CDF) measurements, when using only the LSTM-NN model, the positioning error of 95% of the experimental data is >15 cm; while using the LSTM-NN with PCA model, the error is reduced to <5 cm. In addition, we also experimentally demonstrate that the proposed real-time VLP system can also be used to predict the direction and the trajectory of the moving Rx.

On the utility of partially corrupted flow measurement data arising from adjacent acoustic Doppler current profilers for energy yield assessment

Recommended practice for quantifying the energy resource at a tidal energy site requires the use of multiple instruments deployed across the site. However, the instruments used work by emitting an acoustic pulse and instruments working at the same time have the potential to interfere with each other through a process known as ’cross-talk’. It is important to understand the impact of cross-talk on measurements and how this can be managed and through data processing or suitable positioning of devices. The ReDAPT project conducted a measurement campaign using two Acoustic Doppler Current Profilers (ADCPs) placed upstream of an operational tidal turbine. This aimed to assess the ’in-line’ instrument placement guidelines from IEC 62600-200 for Power Performance Assessment (PPA) in real-world conditions. Consequently, the results within hold potential to support arguments for expanding these zones or adjusting their general dimensions. Despite adhering to industry standards and best practices to eliminate unreliable data in the Quality Control (QC) checks, in both concurrently measuring ADCPs at different time stamps in approximately 15 % of the returned data. This work identified for the first time interference throughout the campaign and quantified subsequent impact on estimates. A method to remove data anomalies caused by interference between closely positioned ADCPs has been developed and demonstrated, resulting in a 7 % variation in estimated Annual Energy Production (AEP). The algorithm effectively removed approximately 90 % of the corrupted measurements. Moving forward, multi-sensor deployments could use the algorithm described to double-check for interference within the data sets, although care should be taken to avoid this by choosing a suitable layout for deployment.

A heuristic method to evaluate consequences for flight control and stability induced by attachment of biologging devices to birds and bats

Abstract Biologging is central to the study of wildlife, but questions remain about the minimization of effects of biologging devices. Rarely considered are changes biologging devices induce on an animal's centre of mass (COM) and resulting losses of flight control and stability. We applied established aeronautical principles to estimate how the COM of a flying bird or bat may be affected by the typical positioning of a biologging device on the neck, back, hips or tail. We then adopted modified thresholds from aerospace engineering to estimate limits beyond which changes to COM result in fitness‐relevant alterations to flight control and stability. Generic models illustrate a trade‐off between the placement and mass of a biologging device that influences flight control and stability. Seven species‐specific examples show the substantial differences in consequences of changes to COM for animals of different sizes and body types. Placement of a device on the tail always resulted in the greatest shift in COM and placement in the centre of the back resulted in the smallest shift. The 5% weight threshold some use for a biologging device provides little room for error in terms of stability and can easily cause dangerous changes to COM. The 3% weight threshold others use causes considerably smaller changes in the COM, but when placed away from the natural COM, still can affect flight control and stability. Researchers interested in minimizing the effects to fitness of wildlife should consider weight, balance and COM when affixing biologging devices. The farther a device is from the natural COM, the smaller it should be relative to the mass of the animal.

Study of hydrocyclone with flushing water device for sand washing of municipal sludge

Municipal sludge particles with size range between 0.045 and 0.2 mm were difficult to be precisely separated due to fine size distribution and high content of organic matter, resulting in low sand recycling efficiency. In view of the above problems, this paper proposed a flushing water device which was settled at the cone section of conventional hydrocyclone, aiming to utilize the supplementary water to strengthen the shear force field. Comparative test results showed that the organic matter content in the underflow product was significantly reduced after the addition of flushing water. Using the organic matter content and the sand recovery rate as the response index, the prediction models were established by using response surface optimization test. The influence order of different parameters on the response index was apex diameter, flushing device position and flow rate. Finally, an underflow product with organic matter content of 3.96 % and sand recovery rate of 48.03 % was obtained under the conditions of optimized parameter combinations. The research results can contribute to the development of a new method of residual sludge disposal that improves the sand washing efficiency and the cost-effectiveness of sludge treatment.

Impact of Antenna Orientation on Localization Accuracy Using RSSI-based Trilateration

The goal of the indoor localization is to determine the position and orientation of people, devices, and mobile robots. With the rise of Industry 4.0, wireless communication technologies have emerged as a rapidly evolving and crucial area for achieving this goal. Various radiocommunication-based technologies, including Bluetooth, Bluetooth Low Energy (BLE), Wi-Fi, Ultra-Wideband (UWB), and ZigBee offer means to indirectly estimate distance. These methods leverage diverse principles such as time-based measurements, signal strength, and angle of arrival. Indoor positioning systems can be categorized into two approaches: distance-based and distance-independent techniques. The Free Space Path Loss (FSPL) model describes the connection between distance and Received Signal Strength Indicator (RSSI). The parameters within this model significantly impact distance estimation and localization accuracy. Therefore, a method that accurately characterizes the model is critical. This work proposes an orientation-based localization technique utilizing RSSI and trilateration. Measurements were conducted between two ESP32 units in various orientations to obtain optimal parameters for each specific scenario. To assess the effectiveness of this approach, two scenarios were evaluated: one considering orientation and another neglecting it. The results show that incorporating orientation information leads to significantly more accurate positioning compared to the orientation-agnostic approach.