Current Track Research Articles

WITHDRAWN: Swimming sports action recognition based on wireless sensor and FPGA

Abstract As an effective field testing, sports-related behavioral observation plays an important role in the life and personal happiness. Normally it is regarded as acts of human task, the task using a sliding window of fixed length split long trip signal. Identifying from the coarse sensor information out of human indication, a make the current track and the wearable device checks conventional motion. In any case, when used in the real world, rack-mounted gadgets presentation usually is not enough. Field Programmable Gate Array (FPGA) for image ready to be applied gradually. For embedded applications in progress is particularly true where the inactivity and power consumption is an important consideration. The image sensor overflows, FPGA sensitive camera built in, may be an important part of image processing performed legally. The camera offers a ready flow of production information, rather than a series of images. In this paper, from the lonely sensor information to recognize and resolve style swimming laps problem. 40 swimmers from various foundations to collect the information of 17 hours. Then use this information to prepare convoluted nerve tissue, to identify the four basic strokes, duration and turning circle. Clearly these results provide the first precise programming to improve the rational and swim sport detection under the approval completely controlled climatic conditions.

Immigrant COVID.

Ad Libitum20 October 2020Immigrant COVIDFREEPaul Rousseau, MDPaul Rousseau, MDCharleston, South Carolina (P.R.)Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M20-4732 Audio Reading - “Immigrant COVID” Audio. Michael A. LaCombe, MD, Annals Associate Editor, reads “Immigrant COVID” by Paul Rousseau, MD Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ SectionsAboutVisual AbstractPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail With fever and cough and gasping breath, he shuffles into the exam room tracing the wall with his hand like a blind man fingering Braille, apologizing that he might have COVID, but the slaughterhouse won't let him work until he's tested, and if he doesn't work, the slaughterhouse notifies the Border Patrol, and yes, he's illegal, five years now, and yes, his wife and three children are also sick, and no, he doesn't have health insurance, and when the swab tickles the back of his throat he coughs and sneezes, and I stumble sideward and ponder the scattered droplets and my family at home. Comments0 CommentsSign In to Submit A Comment Author, Article, and Disclosure InformationAffiliations: Charleston, South Carolina (P.R.)Current Author Address: Paul Rousseau, MD, 1531 Wakendaw Road, Mount Pleasant, SC 29464; e-mail, [email protected]com. PreviousarticleNextarticle Advertisement Audio Reading - “Immigrant COVID” Audio. Michael A. LaCombe, MD, Annals Associate Editor, reads “Immigrant COVID” by Paul Rousseau, MD Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ FiguresReferencesRelatedDetails Metrics 20 October 2020Volume 173, Issue 8Page: 667KeywordsChildrenFeversHealth insurancePharynx ePublished: 4 August 2020 Issue Published: 20 October 2020 Copyright & PermissionsCopyright © 2020 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...

Evolving Best Practices: Engaging the Strengths of Both External and Local Peacebuilders in Track Two Dialogues through Local Ownership

Abstract This article examines best practices in local ownership of Track Two diplomacy. Taking as a starting point the idea that best practices change over time as conflicts and social responses to them change, the article seeks out recent innovations and practices in Track Two diplomacy, focusing on practices of local ownership. A series of two reflective practice workshops with facilitators of Track Two processes offer insights on local ownership in current Track Two diplomacy. More in-depth examination of the Georgian-South Ossetian case illustrates an example of increasing local ownership developing over time during a ten year Track Two process. Together, the reflective practice workshops and the case study suggest team approaches to Track Two diplomacy so that insiders and outsiders work together as a team to facilitate, bringing the strengths of both insiders and outsiders to Track Two processes.

Benchmarking the research track record and level of appointment of Australian medical laboratory science academics

BackgroundBenchmarking across and within universities is a common tool to evaluate performance of a program and maintain accreditation requirements. While teaching remains a primary responsibility of many academics, academic research performance is a major contributor towards career advancement and standards in the medical laboratory science profession. While anecdotal evidence suggests academics are active contributors to the evidence base of the profession, there is a high variability in research output in relation to institution and level of appointment. The aim of the study was to benchmark the research track record of Australian medical laboratory science academics and provide insight into how research productivity informs the level of appointment of academics across their career pathway.MethodsA bibliographic analysis of Australian medical laboratory science faculty websites and corresponding Scopus citation database profiles was conducted. A description of current research track record and relationships with holding a doctorate, academic appointment level, research and teaching interests, and institutional characteristics were explored. Quantitative data and frequencies were analysed using IBM SPSS version 26 to benchmark research track records by academic appointment level.ResultsThere were 124 academics identified from 13 universities who had a teaching and research position in an undergraduate medical laboratory science program in Australia. Academics at the level of lecturer or higher typically held a doctorate (89%). Holding a doctorate strongly influenced the number of publications. The top 20% of researchers authored around half of the overall publications. The majority of academics did not have alignment of their major research and teaching areas however, alignment had no influence on number of publications. There was, however, an inconsistent relationship between metropolitan or regional university location and the number of publications.ConclusionData from this study provides academics with benchmarks for the research track record required at each level of appointment. When drawing conclusions on academic progression, promotion and tenure through research track record it would be mindful to assess each on a case by case basis. Institution (metropolitan versus regional) and research interest appears to influence publication number, h-index and citation scores.

Achieving the Minimum Roughness of Laser Milled Micro-Impressions on Ti 6Al 4V, Inconel 718, and Duralumin.

Titanium-aluminium-vanadium (Ti 6Al 4V) alloys, nickel alloys (Inconel 718), and duraluminum alloys (AA 2000 series) are widely used materials in numerous engineering applications wherein machined features are required to having good surface finish. In this research, micro-impressions of 12 µm depth are milled on these materials though laser milling. Response surface methodology based design of experiment is followed resulting in 54 experiments per work material. Five laser parameters are considered naming lamp current intensity (I), pulse frequency (f), scanning speed (V), layer thickness (LT), and track displacement (TD). Process performance is evaluated and compared in terms of surface roughness through several statistical and microscopic analysis. The significance, strength, and direction of each of the five laser parametric effects are deeply investigated for the said alloys. Optimized laser parameters are proposed to achieve minimum surface roughness. For the optimized combination of laser parameters to achieve minimum surface roughness (Ra) in the titanium alloy, the said alloy consists of I = 85%, f = 20 kHz, V = 250 mm/s, TD = 11 µm, and LT = 3 µm. Similarly, optimized parameters for nickel alloy are as follows: I = 85%, f = 20 kHz, V = 256 mm/s, TD = 8 µm, and LT = 1 µm. Minimum roughness (Ra) on the surface of aluminum alloys can be achieved under the following optimized parameters: I = 75%, f = 20 kHz, V = 200 mm/s, TD = 12 µm, and LT = 3 µm. Micro-impressions produced under optimized parameters have surface roughness of 0.56 µm, 2.46 µm, and 0.54 µm on titanium alloy, nickel alloy, and duralumin, respectively. Some engineering applications need to have high surface roughness (e.g., in case of biomedical implants) or some desired level of roughness. Therefore, validated statistical models are presented to estimate the desired level of roughness against any laser parametric settings.

You Cannot Manage What You Cannot Measure—Developing Central Sterilizing Performance Metrics

Background: Metrics are critical to healthcare, particularly in areas that are highly process oriented. Our hospital’s central sterilizing department functions on standardized processes that have almost no industry specific measurements. Furthermore, the department had no formal internal method for process performance evaluation. A multiphase 6 Sigma DMAIC project was initiated in February 2019 in the central sterilizing department, with ‘phase 1’ being the development of performance metrics to evaluate current state and track future improvement. Methods: A DMAIC team was formed and completed a data inventory that included identifying all existing data sources pertaining to central sterilizing. Sources identified as reliable included count of daily surgical cases, counts of defects based on surgical services communication logs, number of surgical trays processed in the central sterilizing department, and the number of unsterile trays in the department at the start of each 7:00 a.m. shift. Results: A multidisciplinary team including surgeons and senior leadership formed the DMAIC team. Using identified data sources and input from frontline staff and leadership, official metric definitions were created. Weekly defect rates were chosen as a measurement and translated into the number of ready-for-use surgical trays at the time of case setup for every 100 surgical cases. Data from November 2018 through January 20, 2019, demonstrated the mean ready-for-use surgical trays at the time of case setup: for every 100 surgical cases, 96 the surgical trays was ready for use. Further analysis of the data over time demonstrated that variability was out of control. Defects were stratified into 12 categories. Moreover, 6 defects were creating 80% of the issues in trays not being ready: ‘hole in wrapper,’ ‘biohazardous debris,’ ‘nonbiohazardous debris,’ ‘missing instrument,’ ‘incorrect/mislabeled instrument trays,’ and ‘missing indicators.’ Results for unsterile trays at 7:00 a.m. showed that, on average, the central sterilizing department had 100 or more trays at the start of each 7:00 a.m. shift. Conclusions: Without a formal method for data collection, defined metrics, and ongoing analysis, evaluation of performance is based on anecdotal conclusions resulting in missed opportunities for improvement and, subsequently, opportunities for improved patient safety. Regularly published visible dashboards provide a true picture of performance, allowing staff to identify unwanted variation and to put interventions in place so that future variation is better controlled and or prevented. Additionally, having solid metrics, even when no industry ones exist, aid in measuring the effectiveness of improvement efforts, such as the DMAIC project, as they move into subsequent phases.Funding: NoneDisclosures: None

Analysis of Civil Aircraft Terrain Avoidance Warning System “Terrain Terrain” Issue Based on QAR Data

As an important instruction recording device for civil aircraft, Quick Access Recorder (QAR) records the operating status of various aircraft systems. Therefore, QAR data is an important basis for aircraft safety assessment, maintenance inspection and failure analysis[1][2]. The Terrain Avoidance Warning System (TAWS) provides the crew with a near-ground warning based on the aircraft’s current track information (including the aircraft’s current position, air pressure altitude, ground speed and track angle, etc.) and referring to terrain altitude data, obstacle data and airport data information. Generally, the QAR data can be used to obtain a more accurate judgment when a warning occurs in the TAWS system. Through the quantitative analysis of QAR data, this paper finds out the root cause of over speed approaching terrain warning in the flight process of an aircraft.

16. DEVELOPMENT OF VALIDATED SURVEYS TO STANDARDIZE EVALUATION OF GLOBAL HEALTH TRACKS

Introduction Global health (GH) tracks are becoming increasingly common in pediatric residency and fellowship programs around the country. A recent Delphi process 1 identified a consensus definition for GH tracks within pediatric residency programs, determined key educational and institutional components, and established target outcomes for programmatic evaluation. The aim of this project was to develop and validate a set of standardized surveys to be used as an evaluation tool for pediatric GH tracks. Methods The authors, all committee members of the American Association of Pediatric Program Directors Global Health Learning Community (APPD GHLC), created a set of standardized surveys to serve as an evaluation tool to facilitate comparison of resources and outcomes among GH tracks within pediatric residency programs. Based on consensus outcomes identified in a previous Delphi, 1 the authors created surveys for four stakeholder groups: (1) current GH track residents, (2) GH track alumni, (3) GH track directors, and (4) GH track host sites/partners. Surveys sought to assess resident perceptions, educational outcomes, influence of tracks on career paths, and the human and monetary programmatic resources required to run tracks. As initial validation steps, the authors developed survey questions based on previously identified outcomes and input from stakeholders. The survey was reviewed by a survey methodologist to support content validity. To collect evidence of response process validity, structured cognitive interviews were conducted for each survey with 1 or more stakeholder group members with further edits incorporated. Results The resulting surveys will be piloted among three pediatric residency GH tracks in Spring 2020 with subsequent analysis of pilot data planned to assess reliability and further construct validity. Data will be used by individual GH tracks for programmatic improvement and will allow comparison among GH tracks for future research. Conclusion This is the first standardized tool for evaluating GH tracks within pediatric residency programs. The evaluation tool will be available on the APPD GHLC website.

A Multi-GNSS Differential Phase Kinematic Post-Processing Method

We propose a multiple global navigation satellite system (multi-GNSS) differential phase kinematic post-processing method, expand the current Track ability, and finely tune processing parameters to achieve the best results for research purposes. The double-difference (DD) phase formulas of GLONASS are especially formulated, and the method of arc ambiguity resolution (AR) in post-processing is developed. To verify the feasibility of this AR method, a group of static baselines with ranges from 8 m to 100 km and two kinematic tests were used. The results imply that 100% of ambiguities in short baselines and over 90% in long baselines can be fixed with the proposed ambiguity resolution method. Better than a 10-mm positioning precision was achieved for all the horizonal components of those selected baselines and the vertical components of the short baselines, and the vertical precision for long baselines is around 20 to 40 mm. In the posterior residual analysis, the means of the residual root-mean-squares (RMSs) of different systems are better than 10 mm for short baselines and at the range of 10–20 mm for baselines longer than 80 km. Mostly, the residuals satisfy the standard normal distribution. It proves that the new method could be applied in bridge displacement and vibration monitoring and for UAV photogrammetry.

A Visit to Polk Institute.

Ad Libitum18 August 2020A Visit to Polk InstituteJack Coulehan, MDJack Coulehan, MDCenter for Medical Humanities, Compassionate Care, and Bioethics at Stony Brook University, Stony Brook, New York (J.C.)Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M19-0936 Audio Reading - “A Visit to Polk Institute” Audio. Michael A. Lacombe, MD, Annals Associate Editor, reads “A Visit to Polk Institute” by Jack Coulehan, MD Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail It was natural for us to visit the idiotsat Polk Institute. Though abuzzwith curiosity, we took it slowly.First, morons playing table-top gamesin the solarium bustled around us,smiling. Next, came the imbeciles'oversized faces in chairs at the footof their beds. Last, a cavernous hallof cribs with idiots in them, babiesbig enough to thicken our skinswith truth, an important precautionfor doctoring. Nothing is more natural,the idiots told us, than imperfection,and nothing is more solemn than silence.We were aliens with tanks on our backscontaining a gas that protected usfrom human feeling. We knew nothing. Author, Article, and Disclosure InformationAffiliations: Center for Medical Humanities, Compassionate Care, and Bioethics at Stony Brook University, Stony Brook, New York (J.C.)Current Author Address: Jack Coulehan, MD; e-mail, john.[email protected]edu. PreviousarticleNextarticle Advertisement Audio Reading - “A Visit to Polk Institute” Audio. Michael A. Lacombe, MD, Annals Associate Editor, reads “A Visit to Polk Institute” by Jack Coulehan, MD Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ FiguresReferencesRelatedDetails Metrics Cited byImplications of preexisting asthma on COVID-19 pathogenesis 18 August 2020Volume 173, Issue 4Page: 277KeywordsEmotionsGames ePublished: 18 August 2020 Issue Published: 18 August 2020 Copyright & PermissionsCopyright © 2020 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...

The Old Dilemma.

Ad Libitum18 August 2020The Old DilemmaJack Coulehan, MDJack Coulehan, MDCenter for Medical Humanities, Compassionate Care, and Bioethics at Stony Brook University, Stony Brook, New York (J.C.)Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M19-0935 Audio Reading - “The Old Dilemma” Audio. Michael A. Lacombe, MD, Annals Associate Editor, reads “The Old Dilemma” by Jack Coulehan, MD Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail The blade of ethics rips close to your skin.... Author, Article, and Disclosure InformationAffiliations: Center for Medical Humanities, Compassionate Care, and Bioethics at Stony Brook University, Stony Brook, New York (J.C.)Current Author Address: Jack Coulehan, MD; e-mail, john.[email protected]edu. PreviousarticleNextarticle Advertisement Audio Reading - “The Old Dilemma” Audio. Michael A. Lacombe, MD, Annals Associate Editor, reads “The Old Dilemma” by Jack Coulehan, MD Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ FiguresReferencesRelatedDetails Metrics 18 August 2020Volume 173, Issue 4Page: 261 ePublished: 18 August 2020 Issue Published: 18 August 2020 Copyright & PermissionsCopyright © 2020 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...

A Track Initiation Algorithm Using Residual Threshold for Shore-Based Radar in Heavy Clutter Environments

There is a large error in the actual radar trajectory tracking process. Track initiation is the primary problem in trajectory tracking and the first step in target tracking. The current track initiation algorithms are greatly affected by heavy clutter environments, so it is necessary to propose an algorithm to solve the problem of low track initiation efficiency. This paper presents a track initiation algorithm using a residual threshold in heavy clutter environments. The falling probability of measured value and decision threshold are used to determine the correlation window. The angle limiting condition is added to establish the track association, and the residual threshold is used to further eliminate the false tracks. The initial track experiment with the trajectory data in the sea near Rizhao Port shows that the algorithm is superior to the traditional logic method and Kalman filter method in track quality. The experiment uses the AIS buffer zone to calculate track initiation probability and uses the multi-region AIS trajectory data for verification. The experimental result shows that track initiation probability with the proposed algorithm in this paper can reach 92.31%.

Research on Geographic Location Prediction Algorithm Based on Improved Teaching and Learning Optimization ELM

With the rapid development of vehicle-mounted communication technology, GPS data is an effective method to predict the current road vehicle track based on vehicle-mounted data. GPS-oriented vehicle-mounted data position prediction method is currently a hot research work and an effective method to realize intelligent transportation. In this paper, an improvement scheme is proposed based on the problem of falling into local optimization existing in the basic algorithm of teaching and learning optimization algorithm. An interference operator is used to disturb teachers to enhance the kinetic energy of the population to jump out of local optimization. By comparing the performance of GA, PSO, TLBO and ITLBO algorithms with four test functions, the results show that ITLBO has efficient optimization effect and generalization ability. Finally, the ITLBO-ELM algorithm has the best prediction effect by comparing the vehicle GPS data and comparing the experimental algorithms.

Motion tracking of 80-nm-size skyrmions upon directional current injections.

Nanometer-scale skyrmions are prospective candidates for information bits in low-power consumption devices owing to their topological nature and controllability with low current density. Studies on skyrmion dynamics in different classes of materials have exploited the topological Hall effect and current-driven fast motion of skyrmionic bubbles. However, the small current track motion of a single skyrmion and few-skyrmion aggregates remains elusive. Here, we report the tracking of creation and extinction and motion of 80-nm-size skyrmions upon directional one-current pulse excitations at low current density of the order of 109 A m-2 in designed devices with the notched hole. The Hall motion of a single skyrmion and the torque motions of few-skyrmion aggregates have been directly revealed. The results exemplify low-current density controls of skyrmions, which will pave the way for the application of skyrmions.

Research of the Fatigue Life of Welded Joints of High Strength Steel S960 QL Created Using Laser and Electron Beams.

This study investigated the fatigue life of welded joints, in particular, the welds of the high-strength steel S960 QL. The welds were created using unconventional technologies by utilising laser and electron beams. The direct application of the research is intended to be carried out through implementing the results towards the design of tracks for the track-wheel chassis of the demining system Božena 5. The producer’s experience shows the damage found in the current track design. The damage occurred during reversing the vehicle on a sand surface. Our goal was to solve this problem. The information acquired in this research will be a very important input factor for further designs of the track made of the tested material and its welds. The analysis of the residual stresses was also part of this study. The experimental research of the tested material’s fatigue life and welded joints was realised on the specimens loaded using cyclic bending and cyclic torsion. These loads were dominant during the track operation. The fatigue life of the tested material was detected using a device designed by us. The measurement results were processed in the form of the Wöhler’s S–N curves (alternating stress versus number cycles to failure) and compared with the current regulations issued by the International Institute of Welding (IIW) in the form of the FAT curves (IIW fatigue class). The achieved research results indicate that the modern welding technologies (laser and electron beams) used on the high-strength steel had no principal influence on the fatigue life of the tested material.

COVID-19, Prison Visits, and the Value of a Cup of Coffee

The simple act of being able to walk downstairs and buy coffee crystalizes a feeling I have had during my days on the COVID-19 ward.

Technology and determination of the applicability of stone blowing at the current track maintenance

Technology and determination of the applicability of stone blowing at the current track maintenance

Measurement, analysis, and model updating based on the modal parameters of high-speed railway ballastless track

Abstract The occurrence of high-speed railway wheel-rail defects is closely related to the vibration characteristics of the track structures, which can be affected by service conditions. Theoretical models are the main measures to study this problem. However, due to the modeling simplification and initial parameters used in current track modeling methods, it is difficult to accurately simulate the vibration characteristics of in-serving track structures. To supplement this shortcoming, by conducting a series of research works, including: (1) a modal test on a ballastless track; (2) the sensitivity analysis of the modal parameters of the ballastless track; (3) designing and carrying out of three model updating schemes based on the measured modal parameters, this paper obtained a model that is highly consistent with the vibration characteristics of the actual track structure. The research work can provide a reliable reference for modal testing, vibration analysis and model updating of ballastless track structures.

The Italian Belle.

On Being a Doctor21 April 2020The Italian BelleAna Elizabeth Tucker, MDAna Elizabeth Tucker, MDJohns Hopkins Bayview, Baltimore, Maryland (A.E.T.)Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M19-2137 Audio Reading - “The Italian Belle” Audio. Virginia L. Hood, MD, a physician from the University of Vermont, reads “The Italian Belle” by Ana Elizabeth Tucker, MD Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail “Ready for the next one?”Glancing up, I saw the attending triage leaning in the doorway. Having just finished evening rounds in the cardiac intensive care unit, my resident and I were camped out at computers clicking “refresh” and awaiting the next batch of severe laboratory abnormalities. I was nearing the end of my last month as an intern and had been racking up hours in house that I knew were not healthy. After weeks in the cardiac ICU, my life had started to adopt an anesthetic consistency—rounds, admission, orders, run the board, admission, orders, sign out, sleep, repeat—a life ... Author, Article, and Disclosure InformationAffiliations: Johns Hopkins Bayview, Baltimore, Maryland (A.E.T.)Corresponding Author: Ana Elizabeth Tucker, MD, 301 Mason Lord Drive, Johns Hopkins Bayview Medical Center, Baltimore, MD 21224; e-mail, [email protected]edu. PreviousarticleNextarticle Advertisement Audio Reading - “The Italian Belle” Audio. Virginia L. Hood, MD, a physician from the University of Vermont, reads “The Italian Belle” by Ana Elizabeth Tucker, MD Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ FiguresReferencesRelatedDetails Metrics 21 April 2020Volume 172, Issue 8Page: 565-566KeywordsHeartHoneyPacemakersResearch laboratoriesRunningSaltsSleepSoapsSymptomatic bradycardiaTriage ePublished: 21 April 2020 Issue Published: 21 April 2020 Copyright & PermissionsCopyright © 2020 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...

An Improved Model Predictive Current Control for PMSM Drives Based on Current Track Circle

Model predictive current control (MPCC) is a high-performance control strategy for permanent-magnet synchronous motor (PMSM) drives, with the features of quick response and simple computation. However, the conventional MPCC results in high torque and current ripples. This article proposes an improved MPCC scheme for PMSM drives. In the proposed scheme, the back electromotive force is estimated from the previous stator voltage and current, and it is used to predict the stator current for the next period. To further improve the steady state and dynamic performance, the proposed MPCC selects the optimal voltage vector based on a current track circle instead of a cost function. Compared with the calculation of cost function, the prediction of the current track circle is simple and quick. The proposed MPCC is compared with conventional MPCC and a duty-circle based MPCC by simulation and experiment in the aspect of converter output voltage and sensitivity analysis. Results prove the superiority of the proposed MPCC and its effectiveness in reducing the torque and current ripples of PMSM drives.