Wrong dose
*The number of deviations refers to one deviation of the same type per patient even if more deviations of same type exist with one patient, for example, if one patient had wrong dose dispensed for two medications, this was counted as one deviation.
†Deviations which also classify as actual medication errors.
COW, computer on wheels; eMAR, electronic Medication Administration Record.
We also observed deviations from the storage of patients’ own medication (home-brought). According to policy, patients’ own medication should be stored in the COW or the medication room. We registered a 96% deviation rate from this policy ( table 2 ). Patients’ own medications were not integrated in the BCMA and were not barcoded or scanned.
Data source: observational tool and field notes.
Technology-related factors were registered with the observational tool and deviations were found in 38 observations (18%). These included low laptop battery in 28 observations (13%), system freezing in seven observations (3%), malfunctioning barcode scanner in two observations and the barcode scanner was unavailable for administration in one observation ( online supplemental appendix 4 ). Software problems included slow response and the need for multiple clicking after scanning each medication. Nurses used the laptop mousepad to navigate the eMAR, and this extensive clicking was perceived by the nurses as frustrating. The size of the COW was deemed to slow the administration process and lead to deviations.
Medication rooms were located some distance from the nursing stations and patient rooms. The nurses ran back and forth to the medication room multiple times during an administration round to rectify deviations in the COW. Other disruptive environmental factors affecting the BCMA workflow were the fact that the patient drawers were too small and could not contain all the patient medications. We also observed that the work surface of the COWs and at the nursing stations were often untidy and contained single-dose units from past administrations or falsely dispensed medications.
Several nurses admitted that they did not use the barcode scanning equipment on a daily basis. If the ward was particularly busy, nurses tended to discard BCMA because they perceived it slowed down the medication administration. However, nurses who used BCMA regularly valued the automated medication verification because it confirmed that the right patient would receive the right medication.
The probable causes of BCMA deviations and their data sources are listed in table 3 . Under task-related deviations, the failure to scan medications during administration occured because scanning was discarded during dispensing; a non-streamlined workflow during administration was caused by a mismatch with the tasks required during administration. Causes for organisational deviations were associated with unclear or poorly described policies, health professionals unaware of policies or the policy was incompatible with workflow. Even when the policy was clear and excluding, deviations occurred; for example, the policy stated that only the prescribed dose should be dispensed, however occasionally whole tablet blisters were dispensed in the COW.
Probable causes to barcode medication administration policy deviations according to the SEIPS categories
Probable cause | Example from observation/description | Data source |
Scanning discarded during dispensing | Medications which were dispensed without scanning in the eMAR failed to scan during administration | Observational tool |
Workflow not adopted to required tasks during administration | Nurse makes multiple runs back and forth to the medication room to retrieve not dispensed medications which interrupts the workflow and may affect patient safety | Observational tool Nurses’ comments |
Suboptimal task performance | Voluminous medications (such as infusion bags, inhalers, eye drops) are routinely not scanned during dispensing because they are retrieved during administration | Observational tool Nurses’ comments |
Dispensing practices not adopted to nurse’s workload, resulted in normalising deviations | Manual labelling of medications during dispensing on ward was challenging to carry out without workarounds | Observational tool |
Non-standardised dispensing process resulted in frequent deviations | Medication not barcode labelled; scanning failure; wrong dose dispensed; wrong medication dispensed; medication not dispensed; wrong label attached | Observational tool |
Unclear procedures or task not assigned | Varying practice between the wards on updating the dispensed medications in the COW due to recent changes in the eMAR | Observational tool Nurses’ comments Field notes |
Poor routines/not followed routines for changing the room number on patient drawer | Room number on patient drawer was another patient’s room number (Each patient drawer was labelled with room number and this was the first step in identifying the patient’s medications) | Observational tool |
Unaware of hospital policies | Patient’s own medications stored in the patient room. Due to policy, patients’ own medication should be stored in the COW or the medication room | Observational tool |
Poor charging routines or non-compliance with routine | The laptop battery was low either at the start or during administration | Observational tool |
eMAR usability issues | Slow eMAR response and need for multiple clicking after scanning each medication | Field notes |
The scanners were not wireless and limited the patient ID scanning | Nurse scanned medications prior to entering the patient room and administered medications while the COW was in the hallway, meaning that the patient ID wristband was not scanned | Field notes |
Suboptimal COW design | Nurses often avoided to bring the bulky COW into the patient room when administering few or one single medication The COW design was cumbersome for the desired workflow of entering patient rooms during administration rounds The COW contained medications for all patients which combined with scanning not being used is a risk for patient safety | Field notes Nurses’ comments |
Medication room location affects task efficiency and time spent administering medications | The medication room was located far from the nursing station and most of the patient rooms. This resulted in slower administration and storage of random medications in the nursing station to avoid going back and forth to the medication room | Observational tool Field notes |
Patient drawer size does not allow appropriate BCMA use | The small size patient drawer led to deviations such as not dispensing the medications because only small forms of oral medications and ampoules were dispensed in the patient drawer, whereas voluminous medications were retrieved during administration | Observational tool Field notes Nurses’ comments |
Non-specific medication storage policy | Random single-unit doses stored on the desk in the nursing station or on the COWs and were obtained from here in case something was missing during administration. Unsafe practice as the single doses are easy to mix up when stored randomly on the COW during administration | Field notes |
Non-standardised dispensing allows variations | Variations in performance between nurses and inconsistency in dispensing medications for the same nurse | Observational tool Field notes Nurses’ comments |
BCMA slower than manual verification—leading to user dissatisfaction | Nurse did not use the BCMA at all during the whole medication round Nurse admitted to not using the BCMA on regular basis but used it during observation period | Observational tool Field notes Nurses’ comments |
BCMA, barcode medication administration; COW, computer on wheels; eMAR, electronic Medication Administration Record.
Probable causes for deviations associated with technology were poor or unclear charging routines, the scanner was not mobile but attached to the laptop, and software usability issues. In addition, the design of the COW, including its large/bulky size, sometimes prevented nurses from scanning the patient ID wristband at the bedside. Furthermore, the undersized patient drawer led to dispensing omission because there was insufficient capacity to store all the medicines. Nurse-related deviations were caused by the slow BCMA process, which led to refraining from scanning or to skip the technology use. These factors all conflicted with patient safety during medication dispensing and administration.
We observed policy deviations which affected 6 of 10 patients during dispensing and 7 of 10 patients during medication administration. The causes to policy deviations were related to a complex dispensing process, slow or cumbersome BCMA procedure, suboptimal technology design and non-specific policy description. Working with suboptimal solutions in a busy environment, it was hard for the nurses not to deviate from policies, which explains why deviations were normalised in practice.
Despite these imperfections, our findings suggest that when the scanning of medications and ID wristbands was used, it offered benefits to patient safety by preventing the administration of wrong dispensed medication for 5% of the patients.
The lack of standardised delivery of dispensed doses lead to several variations in how the medications were dispensed in the COW. Patterson et al 27 found that BCMA made it easier to anticipate others’ actions and detect erroneous actions. In our study, however, it was difficult for other nurses to take for granted that the medications dispensed by a fellow nurse were correct. To compensate for the uncertainty, the nurses had to manually reconfirm doses before administering to patients. This practice undermines the purpose of BCMA.
The scanning rates in our study, that is, 71% for medications, 91% for scannable doses and 80% for patient ID wristbands, are considerably lower than the 95% standard goal for scanning medications and patients. 28 In a recent observational study of BCMA at a UK hospital, Barakat and Franklin registered scanning rates for medications of 83%, scannable doses of 95% and patient verification of 100%. 29 Although Barakat and Franklin had a smaller sample size, their study was undertaken with a similar ward-stock dispensing process and BCMA technology design to our study, which makes the rates broadly comparable.
A recent national study of medication errors in Norwegian hospitals, where BCMA was not used, found that 70% of all medication errors occurred during the medication administration stage. 3 We suggest that many of these errors, such as wrong dose, wrong patient and wrong medication during administration, could have been avoided if BCMA had been implemented. However, even if the technology is used accurately, hospitals may still fail to achieve the full benefits of BCMA to patient safety and unintended consequences may arise from technology implementation, 18 both demonstrated in our findings. In the current study, the technology was used as intended in only half of medication administrations. These deviations often originated in the dispensing process, such as not dispensed medications, wrong medication dispensed and wrong dose dispensed, and consequentially resulted in new deviations even when the BCMA was used correctly during medication administration.
The availability of functioning hardware is essential for the BCMA to have a preventive effect on errors. We identified a reoccurring problem with laptops not being charged and borrowing of scanners across wards, but these were not the main cause of technology-related deviations. The most important cause was the design of the technology like the bulky COW and the fact that scanners were not wireless. Those design issues limited the staffs’ efficiency during medication administration. This may explain why 20% of patient ID wristbands were not scanned during observation. Others have also described the size of the medication cart getting in way of efficient use of BCMA. 4 18 One observational study concluded that nurses uniformly believed that manually confirming patient identity took less time than wheeling the large medication cart in the patient room. 27
The distant medication rooms indirectly affected patient safety because retrieving of missing medications in the COW took a long time and led to medication omissions. Other environmental factors were in direct conflict with patient safety. Dispensing omissions were unavoidable because medications larger in size (eg, eyedrops, inhalers or syringes) could not fit in the small pocket of the COW patient drawers. Such environmental characteristics have affected medication safety in other studies as well. 30
Our nurses also expressed that BCMA prolonged the time they spent on medication administration. Compared with others that used automated dispensing cabinets, 18 or pharmacy-operated dispensing, 12 it is important to stress that nurses in our study had more tasks to attend to during the dispensing process (eg, packaging, labelling, dispensing in the correct compartment of the patient drawer). This is likely to explain the high proportion of dispensing deviations in the current study.
This study demonstrates variations among nurses in their BCMA use: from not using the BCMA in entire administrations, to partial use, to those who were fully compliant. Much of the variability can be explained by doses lacking barcodes and that the policies allowed for too many variations in the workflow. In the study of Barakat and Franklin, the BCMA led to less variability in how nurses undertake medication administration. 29 Some of this difference may be explained by safety culture differences, for example, if the BCMA technology is not used by all nurses, such as found in our study, it could result in being a burden to the workflow rather than a safety initiative. Lyons et al 31 have also described a similar performance variability among nurses within the use of other medication administration technologies, and addressed that this adaptive behaviour could be a source of resilience, compensating for the weaknesses of the system, but raised concerns that it could also lead to unsatisfactory outcomes.
Having the advantage of studying the use of BCMA within the actual setting, this study may provide implications to technology implementation and strategies for improvement.
The mixed-method approach provided insight into the nurses’ BCMA use and understanding of the context in which deviations occur. The added value of using both the qualitative and quantitative data was that it identified frequency of deviations and their probable causes. Our observational tool allowed the detection of ‘normal’ deviations in practice (eg, dispensing wrong dose of medications) that often remain undetected because they are not identified using standard methods such as incident reports and chart reviews. 35 Previous studies have demonstrated that BCMA can reduce medication error rates. 4 5 7 8 In our study, the identified policy deviations indicate that workarounds occur due to system flaws that produce latent conditions which could ultimately lead to serious medication errors. However, focusing on policy deviations rather than medication errors is also a limitation because there is no direct measure of the impact of BCMA to patient safety.
Other limitations are acknowledged. First, there could be differences among observers, either in their data collection or in their interpretation and knowledge of local policy. Observers were carefully trained in observational techniques 36–38 and familiarised with local medication management policies to minimise such effect. Second, the presence of an observer might have influenced the nurses to consciously or unconsciously modify their behaviour. 39 Nurses were aware of being observed while administering medications, and the expected change in behaviour would have been in the direction of better compliance with BCMA use. Some nurses indicated that they were using the technology because they were being observed. However, the findings associated with the medication dispensing were not affected by the observation because this activity took place prior to the observation period that is, usually undertaken by nurses from the previous shift.
We studied an eMAR paired with BCMA technology in a hospital with a traditional ward-based medication dispensing operated by nurses. It is likely that our data will not be generalisable to organisations that use a pharmacy-operated or automated medication dispensing. On the other hand, hospitals that use a ward-based dispensing system can value from our findings, as there is limited research on the BCMA technology use in a ward-based medication dispensing.
This study provides an in-depth understanding of how the BCMA is used in the clinical environment. We identified policy deviations for over half of the observations, such as not scanning the patients or the medications, omission of dispensing, or wrong dose dispensed. We also identified variations in how nurses used BCMA. Deviations were caused with unclear policies, policies that interfere with appropriate BCMA use, including the labor-intensive dispensing process, as well as problems with technology design. Our findings suggest that several factors in the work system need reassessment and adaptation to nurses’ workflow. Deviations are expected with technology implementation in any complex system. As such, analysing policy deviations in practice is an important method of identifying and addressing system weaknesses in order to achieve the full benefits of BCMA in terms of patient safety.
The authors thank the nursing staff for their participation in the study. We also would like to acknowledge the contributions provided by the staff from the Southern and Eastern Norway Pharmaceutical Trust and the Department of Information and Communication Technology at the hospital.
Contributors: AM and AGG conceived of the presented idea. KT, LM and AGG were involved in planning and supervising the work. AM took lead in the data collection, analysis and in writing the manuscript. All authors have read and approved the final version of the manuscript.
Funding: This study was internally funded.
Competing interests: None declared.
Provenance and peer review: Not commissioned; externally peer reviewed.
Supplemental material: This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.
Ethics statements, patient consent for publication.
Not required.
The study was approved by the institutional data protection board.
08-20-2024 TECH
New systems can help surface relevant research papers and quickly understand what they have to say.
[Photo: Nikish Hiraman/peopleimages.com/Adobe Stock]
BY Steven Melendez 7 minute read
For students and professional scholars alike, starting a new research project typically means digging through academic literature to understand what others have already written.
That can take a considerable amount of time, with researchers tracking down and combing through journal articles to begin their research and contextualize their own findings. But a growing collection of AI-powered tools aims to make that process easier. These new tools can help researchers more quickly find relevant papers, pull out relevant information from them, or both.
“It can be a really helpful way to get started with research, especially for students who aren’t familiar with the research process,” says Breanne Kirsch, director of the library at Illinois College. “As long as they’re taught how to use it in an ethical way, and that they can then expand beyond what it does.”
A tool called Elicit can help researchers conduct what are called systematic reviews , which involve going through copious amounts of published research to find an answer to a question, like how a particular drug affects a medical condition. “It’s all very, very manual,” says James Brady, head of engineering at Elicit. “It takes teams of people many months, and you know, costs hundreds of thousands or millions of dollars to do these things.”
Elicit can make that process much faster, and also help researchers by quickly finding and summarizing published papers related to a particular question. It can also generate tables describing a whole set of relevant papers, with columns for data points like algorithms and statistical techniques used, variables examined, and the number of participants in experiments.
The company recommends researchers still look at the original papers, and Brady emphasizes that the tool doesn’t replace the human judgment and analysis necessary to scientific research. “It’s not like you take the final step of Elicit and hit the publish button and then it ends up in Nature or something,” he says, but it can still greatly speed the process of sifting through and understanding prior work.
Understanding how AI can help academic research is part of a larger industry question of how and when the technology can replace or supplement traditional web search tools. And since the 1990s , computer scientists have realized that the academic publishing landscape—where scholars cite each other’s papers and publish in journals with a particular reputation in a particular field—isn’t that different from the internet ecosystem . That means techniques for finding relevant materials, minimizing AI errors and hallucinations, and presenting useful and verifiable results to the user may transfer from academia to the broader web.
ABOUT THE AUTHOR
Steven Melendez is an independent journalist living in New Orleans. More
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… (ICSPS), 2010 2nd …
Md Kafiul Islam
International Journal of Science Technology & Engineering
IJSTE - International Journal of Science Technology and Engineering
Mobile cameras are being used now-a-days to scan barcodes to retrieve the product details. But the drawback is mobile cameras are made by a charge coupled device which is does not have the ability to handle out of focus and blur images. In this project, out of focus and blur images are restored using a dynamic template matching algorithm using directed graphical model. The directed graphical model is used to determine the relationship between state variable from blurred waveform at specific blur level and observation sequence. A varying program based inference algorithm is used to recover the optimal state sequence and hence the system works in real-time.
Proceedings / IEEE Workshop on Applications of Computer Vision. IEEE Workshop on Applications of Computer Vision
Ender Tekin
Most camera-based systems for finding and reading barcodes are designed to be used by sighted users (e.g. the Red Laser iPhone app), and assume the user carefully centers the barcode in the image before the barcode is read. Blind individuals could benefit greatly from such systems to identify packaged goods (such as canned goods in a supermarket), but unfortunately in their current form these systems are completely inaccessible because of their reliance on visual feedback from the user.To remedy this problem, we propose a computer vision algorithm that processes several frames of video per second to detect barcodes from a distance of several inches; the algorithm issues directional information with audio feedback (e.g. "left," "right") and thereby guides a blind user holding a webcam or other portable camera to locate and home in on a barcode. Once the barcode is detected at sufficiently close range, a barcode reading algorithm previously developed by the authors...
Journal of Computer Science IJCSIS , Rizwan Mukati
Barcodes and RFIDs, the two most frequently used " Automatic Identification and Data Capture (AIDC) " techniques based on " Assigned " properties, are being used nearly for the last five decades, in the supply-chain, distribution and manufacturing processes. In this paper, an in-depth look, their pros and cons and their suitability in the given processes, have been presented.
Proceedings / Canadian Conference on Computer and Robot Vision. Canadian Conference on Computer and Robot Vision
The 1D barcode is a ubiquitous labeling technology, with symbologies such as UPC used to label approximately 99% of all packaged goods in the US. It would be very convenient for consumers to be able to read these barcodes using portable cameras (e.g. mobile phones), but the limited quality and resolution of images taken by these cameras often make it difficult to read the barcodes accurately. We propose a Bayesian framework for reading 1D barcodes that models the shape and appearance of barcodes, allowing for geometric distortions and image noise, and exploiting the redundant information contained in the parity digit. An important feature of our framework is that it doesn't require that every barcode edge be detected in the image. Experiments on a publicly available dataset of barcode images explore the range of images that are readable, and comparisons with two commercial readers demonstrate the superior performance of our algorithm.
Yuri Matveev , Kukharev Georgy , Georgy Kukharev
In this paper we propose a simple method for generating standard type linear barcodes from facial images. The method uses the difference in gradients of image brightness. It involves averaging the gradients into a limited number of intervals, quantization of the results into the range of decimal numbers from 0 to 9, and table conversion into the final barcode. The proposed solution is computationally low-cost and does not require the use of any specialized image processing software, which makes it possible to generate facial barcodes in mobile systems. Results of tests conducted on the Face94 database and a database of composite faces at different ages show that the proposed method is a new solution for use in real-world practice. It ensures the stability of the generated barcodes against changes of scale, pose and mirroring of facial images, as well as changes of facial expressions and shadows on faces from local lighting.
IJSRD - International Journal for Scientific Research and Development
In this Review paper discusses about the last few years, Two-Dimensional (2D) codes to get the importance in the industrial sector, and the greater storage capacity information gradually replace many applications of One Dimensional Barcode. Quick response (QR) codes are one of the most popular types of 2D codes. QR Code widely used in many commercial applications due to their highspeed decoding.
International Journal of Latest Technology in Engineering, Management & Applied Science -IJLTEMAS (www.ijltemas.in)
This paper presents designing a Color Barcode for Mobile Applications, 2D barcodes have gained popularity as one of the key pervasive technologies for mobile applications on smart phones. They can be used as shortcuts to URL links, a means to store contact information for easy transfer admission tickets or boarding passes and tokens for retrieving digital information, such as public transportation timetables or fresh produce production information, either directly from the barcode itself or through a networked database server. Most mobile applications use black-and-white 2D barcodes that carry only a limited amount of encoded data. A color barcode framework for mobile phone applications by exploiting the spectral diversity aborted by the cyan (C), magenta (M), and yellow (Y) print colorant channels commonly used for color printing and the complementary red (R),green (G), and blue (B) channels, respectively, used for capturing color images. Specifically, we exploit this spectral diversity to realize a threefold increase in the data rate by encoding independent data in the C, M, and Y print colorant channels and decoding the data from the complementary R, G and B channels captured via a mobile phone camera. To mitigate the effect of cross-channel interference among the printcolorant and capture color channels, we develop an algorithm for interference cancellation. To estimate the model parameters required for crosschannel interference cancellation, we propose two alternative methodologies: a pilot block approach that uses suitable selections of colors for the synchronization blocks and an expectation maximization approach that estimates the parameters from regions encoding the data.
Student attendance play significant role in order to justify academic outcome of a student and college as overall. Unfortunately, there is no automated attendance record keeping application available in colleges. There is a need for a tool to systematically keep the students attendance record due to increasing number of college students The project that we are going to make is to help the teachers in our college to avoid maintaining the registry book. This project uses a barcode scanner. B.B.S.A.S uses Barcode scanner to take the attendance of students entering the lab. Each student's ID card will have a barcode at the back side of it. This barcode contains unique data of the student such as roll number, branch and year. Etc. Student will scan their barcode at the end so that the student can't cheat. The display screen will show the attendance of the particular student after scanning his/her barcode. Teachers and administrator will only have access to the system with their respective login ID's and passwords.
International Journals for Researchers [ER Publication, WOAR Journals, IJEAS and IJEART]
Abstract— Radio frequency identification (RFID) is a rapidly emerging technology which allows productivity and convenience. Radio Frequency Identification (RFID) is a new generation of Auto Identification and Data collection technology which helps to automate business processes and allows identification of large number of tagged objects like books, using radio waves. This paper proposes RFID Based University Library Management System that would allow fast transaction flow and will make it easy to handle the issue and return of books from the library without much intervention of manual book keeping which benefits by adding properties of traceability and security. The proposed system is based on RFID readers and passive RFID tags that are able to electronically store information that can be read with the help of the RFID reader. This system would be able to issue and return books via RFID tags and also calculates the corresponding fine associated with the time period of the absence of the book from the library database.
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Jari Kangas
iaeme iaeme
Rob Kitchin
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The blades of propellers and wind turbines are designed based on aerodynamics principles that were first described mathematically more than a century ago. But engineers have long realized that these formulas don’t work in every situation. To compensate, they have added ad hoc “correction factors” based on empirical observations.
Now, for the first time, engineers at MIT have developed a comprehensive, physics-based model that accurately represents the airflow around rotors even under extreme conditions, such as when the blades are operating at high forces and speeds, or are angled in certain directions. The model could improve the way rotors themselves are designed, but also the way wind farms are laid out and operated. The new findings are described today in the journal Nature Communications , in an open-access paper by MIT postdoc Jaime Liew, doctoral student Kirby Heck, and Michael Howland, the Esther and Harold E. Edgerton Assistant Professor of Civil and Environmental Engineering.
“We’ve developed a new theory for the aerodynamics of rotors,” Howland says. This theory can be used to determine the forces, flow velocities, and power of a rotor, whether that rotor is extracting energy from the airflow, as in a wind turbine, or applying energy to the flow, as in a ship or airplane propeller. “The theory works in both directions,” he says.
Because the new understanding is a fundamental mathematical model, some of its implications could potentially be applied right away. For example, operators of wind farms must constantly adjust a variety of parameters, including the orientation of each turbine as well as its rotation speed and the angle of its blades, in order to maximize power output while maintaining safety margins. The new model can provide a simple, speedy way of optimizing those factors in real time.
“This is what we’re so excited about, is that it has immediate and direct potential for impact across the value chain of wind power,” Howland says.
Modeling the momentum
Known as momentum theory, the previous model of how rotors interact with their fluid environment — air, water, or otherwise — was initially developed late in the 19th century. With this theory, engineers can start with a given rotor design and configuration, and determine the maximum amount of power that can be derived from that rotor — or, conversely, if it’s a propeller, how much power is needed to generate a given amount of propulsive force.
Momentum theory equations “are the first thing you would read about in a wind energy textbook, and are the first thing that I talk about in my classes when I teach about wind power,” Howland says. From that theory, physicist Albert Betz calculated in 1920 the maximum amount of energy that could theoretically be extracted from wind. Known as the Betz limit, this amount is 59.3 percent of the kinetic energy of the incoming wind.
But just a few years later, others found that the momentum theory broke down “in a pretty dramatic way” at higher forces that correspond to faster blade rotation speeds or different blade angles, Howland says. It fails to predict not only the amount, but even the direction of changes in thrust force at higher rotation speeds or different blade angles: Whereas the theory said the force should start going down above a certain rotation speed or blade angle, experiments show the opposite — that the force continues to increase. “So, it’s not just quantitatively wrong, it’s qualitatively wrong,” Howland says.
The theory also breaks down when there is any misalignment between the rotor and the airflow, which Howland says is “ubiquitous” on wind farms, where turbines are constantly adjusting to changes in wind directions. In fact, in an earlier paper in 2022, Howland and his team found that deliberately misaligning some turbines slightly relative to the incoming airflow within a wind farm significantly improves the overall power output of the wind farm by reducing wake disturbances to the downstream turbines.
In the past, when designing the profile of rotor blades, the layout of wind turbines in a farm, or the day-to-day operation of wind turbines, engineers have relied on ad hoc adjustments added to the original mathematical formulas, based on some wind tunnel tests and experience with operating wind farms, but with no theoretical underpinnings.
Instead, to arrive at the new model, the team analyzed the interaction of airflow and turbines using detailed computational modeling of the aerodynamics. They found that, for example, the original model had assumed that a drop in air pressure immediately behind the rotor would rapidly return to normal ambient pressure just a short way downstream. But it turns out, Howland says, that as the thrust force keeps increasing, “that assumption is increasingly inaccurate.”
And the inaccuracy occurs very close to the point of the Betz limit that theoretically predicts the maximum performance of a turbine — and therefore is just the desired operating regime for the turbines. “So, we have Betz’s prediction of where we should operate turbines, and within 10 percent of that operational set point that we think maximizes power, the theory completely deteriorates and doesn’t work,” Howland says.
Through their modeling, the researchers also found a way to compensate for the original formula’s reliance on a one-dimensional modeling that assumed the rotor was always precisely aligned with the airflow. To do so, they used fundamental equations that were developed to predict the lift of three-dimensional wings for aerospace applications.
The researchers derived their new model, which they call a unified momentum model, based on theoretical analysis, and then validated it using computational fluid dynamics modeling. In followup work not yet published, they are doing further validation using wind tunnel and field tests.
Fundamental understanding
One interesting outcome of the new formula is that it changes the calculation of the Betz limit, showing that it’s possible to extract a bit more power than the original formula predicted. Although it’s not a significant change — on the order of a few percent — “it’s interesting that now we have a new theory, and the Betz limit that’s been the rule of thumb for a hundred years is actually modified because of the new theory,” Howland says. “And that’s immediately useful.” The new model shows how to maximize power from turbines that are misaligned with the airflow, which the Betz limit cannot account for.
The aspects related to controlling both individual turbines and arrays of turbines can be implemented without requiring any modifications to existing hardware in place within wind farms. In fact, this has already happened, based on earlier work from Howland and his collaborators two years ago that dealt with the wake interactions between turbines in a wind farm, and was based on the existing, empirically based formulas.
“This breakthrough is a natural extension of our previous work on optimizing utility-scale wind farms,” he says, because in doing that analysis, they saw the shortcomings of the existing methods for analyzing the forces at work and predicting power produced by wind turbines. “Existing modeling using empiricism just wasn’t getting the job done,” he says.
In a wind farm, individual turbines will sap some of the energy available to neighboring turbines, because of wake effects. Accurate wake modeling is important both for designing the layout of turbines in a wind farm, and also for the operation of that farm, determining moment to moment how to set the angles and speeds of each turbine in the array.
Until now, Howland says, even the operators of wind farms, the manufacturers, and the designers of the turbine blades had no way to predict how much the power output of a turbine would be affected by a given change such as its angle to the wind without using empirical corrections. “That’s because there was no theory for it. So, that’s what we worked on here. Our theory can directly tell you, without any empirical corrections, for the first time, how you should actually operate a wind turbine to maximize its power,” he says.
Because the fluid flow regimes are similar, the model also applies to propellers, whether for aircraft or ships, and also for hydrokinetic turbines such as tidal or river turbines. Although they didn’t focus on that aspect in this research, “it’s in the theoretical modeling naturally,” he says.
The new theory exists in the form of a set of mathematical formulas that a user could incorporate in their own software, or as an open-source software package that can be freely downloaded from GitHub . “It’s an engineering model developed for fast-running tools for rapid prototyping and control and optimization,” Howland says. “The goal of our modeling is to position the field of wind energy research to move more aggressively in the development of the wind capacity and reliability necessary to respond to climate change.”
The work was supported by the National Science Foundation and Siemens Gamesa Renewable Energy.
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Abstract. The paper provides an overview of some latest bar code technology, which involves the insertion of a small RFID (radio-frequency identification) tag. This beneath the skin to enable ...
The use of deep learning (DL) for barcode recognition and analysis has achieved remarkable success and has attracted great attention in various domains. Unlike other barcode recognition methods, DL-based approaches can significantly improve the speed and accuracy of both barcode detection and decoding. However, after almost a decade of progress, the current status of DL-based barcode ...
The main aim of the article is to create awareness among the librarians to use Barcode technology in the library. Barcode is very cost-effective technology can be used by every library. The paper ...
Design: This research paper briefly converses the explanation of the application of Barcode technology in libraries, advantages and its working mechanism. It also tried to discover the technical features of Barcode technology in the library. Findings: Barcode technology is mostly used in the motion system of a library and most successful due to ...
Application of Bar-code technology in libraries is a way to process client requests from fast to fastest. Bar-code technology is mostly used in the circulation system of a library and most successful due to its speed, accuracy and reliability. Bar-coding though comparatively an old technology is one of the significant steps in library ...
The application of barcode technology in circulation system of a library and information centre is most succ essful due to its. speed, accuracy and reliability. Statement of the problem. Library ...
This paper desires to explore the role of barcode technology in blood bank information systems via addressing its upgrade and the consequent impact. Firstly, it briefs the application and effect of barcode technology in blood donation and transfusion service.
Analyze check code calculation method by the following taking the EAN-13 barcode for example, as follows: Design and Implementation of Barcode Management Information System 579. Set: Any digit of the numerical code in barcodes is Xi(i = 1, 2, ... 13). (1) Take the unknown parity bit as the first, from right to left, line up the data (including ...
The linear 1D barcode is the main tagging system for billions of products sold each day. Barcodes have many advantages but require a laser scanner for fast and robust scanning. Solutions exist to read barcodes from cell phones but they assume a carefully framed image within the field of view. This undermines the true potential of barcodes in a wide range of scenarios. In this paper we present ...
Feature papers represent the most advanced research with significant potential for high impact in the field. A Feature Paper should be a substantial original Article that involves several techniques or approaches, provides an outlook for future research directions and describes possible research applications.
The use of barcode technology is comparatively cheaper as compared to other AIDC technologies [23]. This work considers the implementation of barcode technology in a public sector university because it is a cheaper and more viable option for attendance monitoring and asset tracking.
Aim: The main aim of this research paper is to create consciousness among the librarians to use Barcode technology in the library. Design: This research paper briefly converses the explanation of the application of Barcode technology in libraries, advantages and its working mechanism.
Retail Trade for 1972, 1977, and 1982 in a di erence-in-di erence speci cation and. nd that. productivity increased by an average of 4.5% in stores that installed barcode scanners before 1982. This average e ect masks variation both over time and across stores: gains in the year.
Barcode is an identification tool that provides an accurate and timely support of the data requirement for management system. This paper highlights the applications of bar code technology in university libraries of Tamilnadu and the satisfaction level of the staff. This study discusses the benefits of barcode technology and highlights the ...
ABSTRACT The use of deep learning (DL) for barcode recognition and analysis has achieved remarkable. success an d h as attracted great attention in various domains. Unlike other b arcode ...
The machine is also intended to provide a more convenient and cost-effective way of viewing data from barcodes than electronic barcode scanners. An individual who wants to inspect data identified by barcode numbers without having to go to a location that provides barcode scanner services can use this computer at any time and from any location [1].
Introduction. Barcode medication administration (BCMA) technology is a health information technology credited for preventing medication errors and promoting patient safety when used accurately. 1 BCMA technology automates the process of verification by scanning the barcode on the medication and the patient identification wristband, thus assisting the nurses in confirming the 'five rights ...
Research Paper on Barcode Technology - Free download as PDF File (.pdf), Text File (.txt) or read online for free. research paper on barcode technology
MIT researchers have discovered how fasting impacts the regenerative abilities of intestinal stem cells, reports Ed Cara for Gizmodo.. "The major finding of our current study is that refeeding after fasting is a distinct state from fasting itself," explain Prof. Ömer Yilmaz and postdocs Shinya Imada and Saleh Khawaled.
Interface (GUI) the barcode type, da ta and size of the image. System is designed to recognize different types of barcode and. display the data once the barcode image is captured. System. also is ...
It's part of Ai2, the AI research institute founded by late Microsoft cofounder Paul Allen, and today it includes features to help users understand papers, like surfacing definitions of ...
The search for life signs and potentially habitable bodies in our solar system and beyond is one of NASA's top priorities. The prime destinations for such exploration are bodies containing liquid water, such as Jupiter's moon Europa and Saturn's moon Enceladus. Initial missions to these "ocean worlds" will be robotic, and because of long communication lags and blackouts, harsh ...
Aim: The main aim of this research paper is to create consciousness among the librarians to use Barcode technology in the library. Design: This research paper briefly converses the explanation of the application of Barcode technology in libraries, advantages and its working mechanism.
This paper first discusses 2D-barcode concepts, types and classifications, major technology players, and applications in mobile commerce. ... Then, it reports a research project to develop a 2D ...
The barcode scanner illuminates the barcode with red light using the illuminator system. The sensor/convertor part of the scanner then detects the reflected light. Once the light is detected, an analog signal is generated. This signal contains varying voltage based on the intensities of the light reflection.
The new findings are described today in the journal Nature Communications, in an open-access paper by MIT postdoc Jaime Liew, doctoral student Kirby Heck, and Michael Howland, the Esther and Harold E. Edgerton Assistant Professor of Civil and Environmental Engineering. "We've developed a new theory for the aerodynamics of rotors," Howland ...
operating with RFID technology was 9.669 s and, when using barcode technology, 24.479 s. Observations of time and motion studies have revealed that many problems affect the timing of RFID and ...